Socket options
==============
-DCCP_SOCKOPT_QPOLICY_ID sets the dequeuing policy for outgoing packets. It takes
-a policy ID as argument and can only be set before the connection (i.e. changes
-during an established connection are not supported). Currently, two policies are
-defined: the "simple" policy (DCCPQ_POLICY_SIMPLE), which does nothing special,
-and a priority-based variant (DCCPQ_POLICY_PRIO). The latter allows to pass an
-u32 priority value as ancillary data to sendmsg(), where higher numbers indicate
-a higher packet priority (similar to SO_PRIORITY). This ancillary data needs to
-be formatted using a cmsg(3) message header filled in as follows:
- cmsg->cmsg_level = SOL_DCCP;
- cmsg->cmsg_type = DCCP_SCM_PRIORITY;
- cmsg->cmsg_len = CMSG_LEN(sizeof(uint32_t)); /* or CMSG_LEN(4) */
-
-DCCP_SOCKOPT_QPOLICY_TXQLEN sets the maximum length of the output queue. A zero
-value is always interpreted as unbounded queue length. If different from zero,
-the interpretation of this parameter depends on the current dequeuing policy
-(see above): the "simple" policy will enforce a fixed queue size by returning
-EAGAIN, whereas the "prio" policy enforces a fixed queue length by dropping the
-lowest-priority packet first. The default value for this parameter is
-initialised from /proc/sys/net/dccp/default/tx_qlen.
DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of
service codes (RFC 4340, sec. 8.1.2); if this socket option is not set,
DCCP_SOCKOPT_GET_CUR_MPS is read-only and retrieves the current maximum packet
size (application payload size) in bytes, see RFC 4340, section 14.
-DCCP_SOCKOPT_AVAILABLE_CCIDS is also read-only and returns the list of CCIDs
-supported by the endpoint (see include/linux/dccp.h for symbolic constants).
-The caller needs to provide a sufficiently large (> 2) array of type uint8_t.
-
-DCCP_SOCKOPT_CCID is write-only and sets both the TX and RX CCIDs at the same
-time, combining the operation of the next two socket options. This option is
-preferrable over the latter two, since often applications will use the same
-type of CCID for both directions; and mixed use of CCIDs is not currently well
-understood. This socket option takes as argument at least one uint8_t value, or
-an array of uint8_t values, which must match available CCIDS (see above). CCIDs
-must be registered on the socket before calling connect() or listen().
-
-DCCP_SOCKOPT_TX_CCID is read/write. It returns the current CCID (if set) or sets
-the preference list for the TX CCID, using the same format as DCCP_SOCKOPT_CCID.
-Please note that the getsockopt argument type here is `int', not uint8_t.
-
-DCCP_SOCKOPT_RX_CCID is analogous to DCCP_SOCKOPT_TX_CCID, but for the RX CCID.
-
DCCP_SOCKOPT_SERVER_TIMEWAIT enables the server (listening socket) to hold
timewait state when closing the connection (RFC 4340, 8.3). The usual case is
that the closing server sends a CloseReq, whereupon the client holds timewait
importance for retransmitted acknowledgments and feature negotiation,
data packets are never retransmitted. Analogue of tcp_retries2.
+send_ndp = 1
+ Whether or not to send NDP count options (sec. 7.7.2).
+
+send_ackvec = 1
+ Whether or not to send Ack Vector options (sec. 11.5).
+
+ack_ratio = 2
+ The default Ack Ratio (sec. 11.3) to use.
+
tx_ccid = 2
- Default CCID for the sender-receiver half-connection. Depending on the
- choice of CCID, the Send Ack Vector feature is enabled automatically.
+ Default CCID for the sender-receiver half-connection.
rx_ccid = 2
- Default CCID for the receiver-sender half-connection; see tx_ccid.
+ Default CCID for the receiver-sender half-connection.
seq_window = 100
- The initial sequence window (sec. 7.5.2) of the sender. This influences
- the local ackno validity and the remote seqno validity windows (7.5.1).
+ The initial sequence window (sec. 7.5.2).
tx_qlen = 5
The size of the transmit buffer in packets. A value of 0 corresponds
DCCPO_TIMESTAMP_ECHO = 42,
DCCPO_ELAPSED_TIME = 43,
DCCPO_MAX = 45,
- DCCPO_MIN_RX_CCID_SPECIFIC = 128, /* from sender to receiver */
- DCCPO_MAX_RX_CCID_SPECIFIC = 191,
- DCCPO_MIN_TX_CCID_SPECIFIC = 192, /* from receiver to sender */
- DCCPO_MAX_TX_CCID_SPECIFIC = 255,
+ DCCPO_MIN_CCID_SPECIFIC = 128,
+ DCCPO_MAX_CCID_SPECIFIC = 255,
};
-/* maximum size of a single TLV-encoded DCCP option (sans type/len bytes) */
-#define DCCP_SINGLE_OPT_MAXLEN 253
/* DCCP CCIDS */
enum {
};
/* DCCP features (RFC 4340 section 6.4) */
-enum dccp_feature_numbers {
+enum {
DCCPF_RESERVED = 0,
DCCPF_CCID = 1,
- DCCPF_SHORT_SEQNOS = 2,
+ DCCPF_SHORT_SEQNOS = 2, /* XXX: not yet implemented */
DCCPF_SEQUENCE_WINDOW = 3,
- DCCPF_ECN_INCAPABLE = 4,
+ DCCPF_ECN_INCAPABLE = 4, /* XXX: not yet implemented */
DCCPF_ACK_RATIO = 5,
DCCPF_SEND_ACK_VECTOR = 6,
DCCPF_SEND_NDP_COUNT = 7,
DCCPF_MIN_CSUM_COVER = 8,
- DCCPF_DATA_CHECKSUM = 9,
+ DCCPF_DATA_CHECKSUM = 9, /* XXX: not yet implemented */
/* 10-127 reserved */
DCCPF_MIN_CCID_SPECIFIC = 128,
- DCCPF_SEND_LEV_RATE = 192, /* RFC 4342, sec. 8.4 */
DCCPF_MAX_CCID_SPECIFIC = 255,
};
-/* DCCP socket control message types for cmsg */
-enum dccp_cmsg_type {
- DCCP_SCM_PRIORITY = 1,
- DCCP_SCM_QPOLICY_MAX = 0xFFFF,
- /* ^-- Up to here reserved exclusively for qpolicy parameters */
- DCCP_SCM_MAX
-};
-
-/* DCCP priorities for outgoing/queued packets */
-enum dccp_packet_dequeueing_policy {
- DCCPQ_POLICY_SIMPLE,
- DCCPQ_POLICY_PRIO,
- DCCPQ_POLICY_MAX
+/* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
+struct dccp_so_feat {
+ __u8 dccpsf_feat;
+ __u8 __user *dccpsf_val;
+ __u8 dccpsf_len;
};
/* DCCP socket options */
#define DCCP_SOCKOPT_SERVER_TIMEWAIT 6
#define DCCP_SOCKOPT_SEND_CSCOV 10
#define DCCP_SOCKOPT_RECV_CSCOV 11
-#define DCCP_SOCKOPT_AVAILABLE_CCIDS 12
-#define DCCP_SOCKOPT_CCID 13
-#define DCCP_SOCKOPT_TX_CCID 14
-#define DCCP_SOCKOPT_RX_CCID 15
-#define DCCP_SOCKOPT_QPOLICY_ID 16
-#define DCCP_SOCKOPT_QPOLICY_TXQLEN 17
#define DCCP_SOCKOPT_CCID_RX_INFO 128
#define DCCP_SOCKOPT_CCID_TX_INFO 192
return __dccp_hdr_len(dccp_hdr(skb));
}
+
+/* initial values for each feature */
+#define DCCPF_INITIAL_SEQUENCE_WINDOW 100
+#define DCCPF_INITIAL_ACK_RATIO 2
+#define DCCPF_INITIAL_CCID DCCPC_CCID2
+#define DCCPF_INITIAL_SEND_ACK_VECTOR 1
+/* FIXME: for now we're default to 1 but it should really be 0 */
+#define DCCPF_INITIAL_SEND_NDP_COUNT 1
+
+/**
+ * struct dccp_minisock - Minimal DCCP connection representation
+ *
+ * Will be used to pass the state from dccp_request_sock to dccp_sock.
+ *
+ * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
+ * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
+ * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
+ * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
+ * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)
+ * @dccpms_pending - List of features being negotiated
+ * @dccpms_conf -
+ */
+struct dccp_minisock {
+ __u64 dccpms_sequence_window;
+ __u8 dccpms_rx_ccid;
+ __u8 dccpms_tx_ccid;
+ __u8 dccpms_send_ack_vector;
+ __u8 dccpms_send_ndp_count;
+ __u8 dccpms_ack_ratio;
+ struct list_head dccpms_pending;
+ struct list_head dccpms_conf;
+};
+
+struct dccp_opt_conf {
+ __u8 *dccpoc_val;
+ __u8 dccpoc_len;
+};
+
+struct dccp_opt_pend {
+ struct list_head dccpop_node;
+ __u8 dccpop_type;
+ __u8 dccpop_feat;
+ __u8 *dccpop_val;
+ __u8 dccpop_len;
+ int dccpop_conf;
+ struct dccp_opt_conf *dccpop_sc;
+};
+
+extern void dccp_minisock_init(struct dccp_minisock *dmsk);
+
/**
* struct dccp_request_sock - represent DCCP-specific connection request
* @dreq_inet_rsk: structure inherited from
* @dreq_iss: initial sequence number sent on the Response (RFC 4340, 7.1)
* @dreq_isr: initial sequence number received on the Request
* @dreq_service: service code present on the Request (there is just one)
- * @dreq_featneg: feature negotiation options for this connection
* The following two fields are analogous to the ones in dccp_sock:
* @dreq_timestamp_echo: last received timestamp to echo (13.1)
* @dreq_timestamp_echo: the time of receiving the last @dreq_timestamp_echo
__u64 dreq_iss;
__u64 dreq_isr;
__be32 dreq_service;
- struct list_head dreq_featneg;
__u32 dreq_timestamp_echo;
__u32 dreq_timestamp_time;
};
* @dccps_timestamp_time - time of receiving latest @dccps_timestamp_echo
* @dccps_l_ack_ratio - feature-local Ack Ratio
* @dccps_r_ack_ratio - feature-remote Ack Ratio
- * @dccps_l_seq_win - local Sequence Window (influences ack number validity)
- * @dccps_r_seq_win - remote Sequence Window (influences seq number validity)
* @dccps_pcslen - sender partial checksum coverage (via sockopt)
* @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
- * @dccps_send_ndp_count - local Send NDP Count feature (7.7.2)
* @dccps_ndp_count - number of Non Data Packets since last data packet
* @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
* @dccps_rate_last - timestamp for rate-limiting DCCP-Sync (RFC 4340, 7.5.4)
- * @dccps_featneg - tracks feature-negotiation state (mostly during handshake)
+ * @dccps_minisock - associated minisock (accessed via dccp_msk)
* @dccps_hc_rx_ackvec - rx half connection ack vector
* @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
* @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
* @dccps_options_received - parsed set of retrieved options
- * @dccps_qpolicy - TX dequeueing policy, one of %dccp_packet_dequeueing_policy
- * @dccps_tx_qlen - maximum length of the TX queue
* @dccps_role - role of this sock, one of %dccp_role
* @dccps_hc_rx_insert_options - receiver wants to add options when acking
* @dccps_hc_tx_insert_options - sender wants to add options when sending
* @dccps_server_timewait - server holds timewait state on close (RFC 4340, 8.3)
- * @dccps_sync_scheduled - flag which signals "send out-of-band message soon"
- * @dccps_xmitlet - tasklet scheduled by the TX CCID to dequeue data packets
- * @dccps_xmit_timer - used by the TX CCID to delay sending (rate-based pacing)
+ * @dccps_xmit_timer - timer for when CCID is not ready to send
* @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
*/
struct dccp_sock {
__u32 dccps_timestamp_time;
__u16 dccps_l_ack_ratio;
__u16 dccps_r_ack_ratio;
- __u64 dccps_l_seq_win:48;
- __u64 dccps_r_seq_win:48;
- __u8 dccps_pcslen:4;
- __u8 dccps_pcrlen:4;
- __u8 dccps_send_ndp_count:1;
+ __u16 dccps_pcslen;
+ __u16 dccps_pcrlen;
__u64 dccps_ndp_count:48;
unsigned long dccps_rate_last;
- struct list_head dccps_featneg;
+ struct dccp_minisock dccps_minisock;
struct dccp_ackvec *dccps_hc_rx_ackvec;
struct ccid *dccps_hc_rx_ccid;
struct ccid *dccps_hc_tx_ccid;
struct dccp_options_received dccps_options_received;
- __u8 dccps_qpolicy;
- __u32 dccps_tx_qlen;
enum dccp_role dccps_role:2;
__u8 dccps_hc_rx_insert_options:1;
__u8 dccps_hc_tx_insert_options:1;
__u8 dccps_server_timewait:1;
- __u8 dccps_sync_scheduled:1;
- struct tasklet_struct dccps_xmitlet;
struct timer_list dccps_xmit_timer;
};
return (struct dccp_sock *)sk;
}
+static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
+{
+ return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
+}
+
static inline const char *dccp_role(const struct sock *sk)
{
switch (dccp_sk(sk)->dccps_role) {
/* Use define here intentionally to get WARN_ON location shown at the caller */
#define tcp_verify_left_out(tp) WARN_ON(tcp_left_out(tp) > tp->packets_out)
-/*
- * Convert RFC3390 larger initial windows into an equivalent number of packets.
- *
- * John Heffner states:
- *
- * The RFC specifies a window of no more than 4380 bytes
- * unless 2*MSS > 4380. Reading the pseudocode in the RFC
- * is a bit misleading because they use a clamp at 4380 bytes
- * rather than a multiplier in the relevant range.
- */
-static inline u32 rfc3390_bytes_to_packets(const u32 bytes)
-{
- return bytes <= 1095 ? 4 : (bytes > 1460 ? 2 : 3);
-}
-
extern void tcp_enter_cwr(struct sock *sk, const int set_ssthresh);
extern __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst);
def_tristate y if (IP_DCCP = y && INET_DIAG = y)
def_tristate m
+config IP_DCCP_ACKVEC
+ bool
+
source "net/dccp/ccids/Kconfig"
menu "DCCP Kernel Hacking"
obj-$(CONFIG_IP_DCCP) += dccp.o dccp_ipv4.o
-dccp-y := ccid.o feat.o input.o minisocks.o options.o \
- qpolicy.o output.o proto.o timer.o ackvec.o
+dccp-y := ccid.o feat.o input.o minisocks.o options.o output.o proto.o timer.o
dccp_ipv4-y := ipv4.o
obj-$(subst y,$(CONFIG_IP_DCCP),$(CONFIG_IPV6)) += dccp_ipv6.o
dccp_ipv6-y := ipv6.o
+dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o
+
obj-$(CONFIG_INET_DCCP_DIAG) += dccp_diag.o
obj-$(CONFIG_NET_DCCPPROBE) += dccp_probe.o
/*
* net/dccp/ackvec.c
*
- * An implementation of Ack Vectors for the DCCP protocol
- * Copyright (c) 2007 University of Aberdeen, Scotland, UK
+ * An implementation of the DCCP protocol
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; version 2 of the License;
*/
+
+#include "ackvec.h"
#include "dccp.h"
+
+#include <linux/dccp.h>
+#include <linux/init.h>
+#include <linux/errno.h>
#include <linux/kernel.h>
+#include <linux/skbuff.h>
#include <linux/slab.h>
+#include <net/sock.h>
+
static struct kmem_cache *dccp_ackvec_slab;
static struct kmem_cache *dccp_ackvec_record_slab;
-struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
+static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
{
- struct dccp_ackvec *av = kmem_cache_zalloc(dccp_ackvec_slab, priority);
+ struct dccp_ackvec_record *avr =
+ kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
- if (av != NULL) {
- av->av_buf_head = av->av_buf_tail = DCCPAV_MAX_ACKVEC_LEN - 1;
- INIT_LIST_HEAD(&av->av_records);
- }
- return av;
+ if (avr != NULL)
+ INIT_LIST_HEAD(&avr->avr_node);
+
+ return avr;
}
-static void dccp_ackvec_purge_records(struct dccp_ackvec *av)
+static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
{
- struct dccp_ackvec_record *cur, *next;
-
- list_for_each_entry_safe(cur, next, &av->av_records, avr_node)
- kmem_cache_free(dccp_ackvec_record_slab, cur);
- INIT_LIST_HEAD(&av->av_records);
+ if (unlikely(avr == NULL))
+ return;
+ /* Check if deleting a linked record */
+ WARN_ON(!list_empty(&avr->avr_node));
+ kmem_cache_free(dccp_ackvec_record_slab, avr);
}
-void dccp_ackvec_free(struct dccp_ackvec *av)
+static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
+ struct dccp_ackvec_record *avr)
{
- if (likely(av != NULL)) {
- dccp_ackvec_purge_records(av);
- kmem_cache_free(dccp_ackvec_slab, av);
+ /*
+ * AVRs are sorted by seqno. Since we are sending them in order, we
+ * just add the AVR at the head of the list.
+ * -sorbo.
+ */
+ if (!list_empty(&av->av_records)) {
+ const struct dccp_ackvec_record *head =
+ list_entry(av->av_records.next,
+ struct dccp_ackvec_record,
+ avr_node);
+ BUG_ON(before48(avr->avr_ack_seqno, head->avr_ack_seqno));
}
+
+ list_add(&avr->avr_node, &av->av_records);
}
-/**
- * dccp_ackvec_update_records - Record information about sent Ack Vectors
- * @av: Ack Vector records to update
- * @seqno: Sequence number of the packet carrying the Ack Vector just sent
- * @nonce_sum: The sum of all buffer nonces contained in the Ack Vector
- */
-int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seqno, u8 nonce_sum)
+int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
+ /* Figure out how many options do we need to represent the ackvec */
+ const u16 nr_opts = DIV_ROUND_UP(av->av_vec_len, DCCP_MAX_ACKVEC_OPT_LEN);
+ u16 len = av->av_vec_len + 2 * nr_opts, i;
+ u32 elapsed_time;
+ const unsigned char *tail, *from;
+ unsigned char *to;
struct dccp_ackvec_record *avr;
+ suseconds_t delta;
+
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+ return -1;
+
+ delta = ktime_us_delta(ktime_get_real(), av->av_time);
+ elapsed_time = delta / 10;
- avr = kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);
+ if (elapsed_time != 0 &&
+ dccp_insert_option_elapsed_time(sk, skb, elapsed_time))
+ return -1;
+
+ avr = dccp_ackvec_record_new();
if (avr == NULL)
- return -ENOBUFS;
+ return -1;
+
+ DCCP_SKB_CB(skb)->dccpd_opt_len += len;
+
+ to = skb_push(skb, len);
+ len = av->av_vec_len;
+ from = av->av_buf + av->av_buf_head;
+ tail = av->av_buf + DCCP_MAX_ACKVEC_LEN;
+
+ for (i = 0; i < nr_opts; ++i) {
+ int copylen = len;
+
+ if (len > DCCP_MAX_ACKVEC_OPT_LEN)
+ copylen = DCCP_MAX_ACKVEC_OPT_LEN;
+
+ *to++ = DCCPO_ACK_VECTOR_0;
+ *to++ = copylen + 2;
+
+ /* Check if buf_head wraps */
+ if (from + copylen > tail) {
+ const u16 tailsize = tail - from;
+
+ memcpy(to, from, tailsize);
+ to += tailsize;
+ len -= tailsize;
+ copylen -= tailsize;
+ from = av->av_buf;
+ }
+
+ memcpy(to, from, copylen);
+ from += copylen;
+ to += copylen;
+ len -= copylen;
+ }
- avr->avr_ack_seqno = seqno;
- avr->avr_ack_ptr = av->av_buf_head;
- avr->avr_ack_ackno = av->av_buf_ackno;
- avr->avr_ack_nonce = nonce_sum;
- avr->avr_ack_runlen = dccp_ackvec_runlen(av->av_buf + av->av_buf_head);
- /*
- * When the buffer overflows, we keep no more than one record. This is
- * the simplest way of disambiguating sender-Acks dating from before the
- * overflow from sender-Acks which refer to after the overflow; a simple
- * solution is preferable here since we are handling an exception.
- */
- if (av->av_overflow)
- dccp_ackvec_purge_records(av);
/*
- * Since GSS is incremented for each packet, the list is automatically
- * arranged in descending order of @ack_seqno.
+ * From RFC 4340, A.2:
+ *
+ * For each acknowledgement it sends, the HC-Receiver will add an
+ * acknowledgement record. ack_seqno will equal the HC-Receiver
+ * sequence number it used for the ack packet; ack_ptr will equal
+ * buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
+ * equal buf_nonce.
*/
- list_add(&avr->avr_node, &av->av_records);
+ avr->avr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
+ avr->avr_ack_ptr = av->av_buf_head;
+ avr->avr_ack_ackno = av->av_buf_ackno;
+ avr->avr_ack_nonce = av->av_buf_nonce;
+ avr->avr_sent_len = av->av_vec_len;
- dccp_pr_debug("Added Vector, ack_seqno=%llu, ack_ackno=%llu (rl=%u)\n",
+ dccp_ackvec_insert_avr(av, avr);
+
+ dccp_pr_debug("%s ACK Vector 0, len=%d, ack_seqno=%llu, "
+ "ack_ackno=%llu\n",
+ dccp_role(sk), avr->avr_sent_len,
(unsigned long long)avr->avr_ack_seqno,
- (unsigned long long)avr->avr_ack_ackno,
- avr->avr_ack_runlen);
+ (unsigned long long)avr->avr_ack_ackno);
return 0;
}
-static struct dccp_ackvec_record *dccp_ackvec_lookup(struct list_head *av_list,
- const u64 ackno)
+struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
{
- struct dccp_ackvec_record *avr;
- /*
- * Exploit that records are inserted in descending order of sequence
- * number, start with the oldest record first. If @ackno is `before'
- * the earliest ack_ackno, the packet is too old to be considered.
- */
- list_for_each_entry_reverse(avr, av_list, avr_node) {
- if (avr->avr_ack_seqno == ackno)
- return avr;
- if (before48(ackno, avr->avr_ack_seqno))
- break;
+ struct dccp_ackvec *av = kmem_cache_alloc(dccp_ackvec_slab, priority);
+
+ if (av != NULL) {
+ av->av_buf_head = DCCP_MAX_ACKVEC_LEN - 1;
+ av->av_buf_ackno = UINT48_MAX + 1;
+ av->av_buf_nonce = 0;
+ av->av_time = ktime_set(0, 0);
+ av->av_vec_len = 0;
+ INIT_LIST_HEAD(&av->av_records);
}
- return NULL;
+
+ return av;
}
-/*
- * Buffer index and length computation using modulo-buffersize arithmetic.
- * Note that, as pointers move from right to left, head is `before' tail.
- */
-static inline u16 __ackvec_idx_add(const u16 a, const u16 b)
+void dccp_ackvec_free(struct dccp_ackvec *av)
{
- return (a + b) % DCCPAV_MAX_ACKVEC_LEN;
+ if (unlikely(av == NULL))
+ return;
+
+ if (!list_empty(&av->av_records)) {
+ struct dccp_ackvec_record *avr, *next;
+
+ list_for_each_entry_safe(avr, next, &av->av_records, avr_node) {
+ list_del_init(&avr->avr_node);
+ dccp_ackvec_record_delete(avr);
+ }
+ }
+
+ kmem_cache_free(dccp_ackvec_slab, av);
}
-static inline u16 __ackvec_idx_sub(const u16 a, const u16 b)
+static inline u8 dccp_ackvec_state(const struct dccp_ackvec *av,
+ const u32 index)
{
- return __ackvec_idx_add(a, DCCPAV_MAX_ACKVEC_LEN - b);
+ return av->av_buf[index] & DCCP_ACKVEC_STATE_MASK;
}
-u16 dccp_ackvec_buflen(const struct dccp_ackvec *av)
+static inline u8 dccp_ackvec_len(const struct dccp_ackvec *av,
+ const u32 index)
{
- if (unlikely(av->av_overflow))
- return DCCPAV_MAX_ACKVEC_LEN;
- return __ackvec_idx_sub(av->av_buf_tail, av->av_buf_head);
+ return av->av_buf[index] & DCCP_ACKVEC_LEN_MASK;
}
-/**
- * dccp_ackvec_update_old - Update previous state as per RFC 4340, 11.4.1
- * @av: non-empty buffer to update
- * @distance: negative or zero distance of @seqno from buf_ackno downward
- * @seqno: the (old) sequence number whose record is to be updated
- * @state: state in which packet carrying @seqno was received
+/*
+ * If several packets are missing, the HC-Receiver may prefer to enter multiple
+ * bytes with run length 0, rather than a single byte with a larger run length;
+ * this simplifies table updates if one of the missing packets arrives.
*/
-static void dccp_ackvec_update_old(struct dccp_ackvec *av, s64 distance,
- u64 seqno, enum dccp_ackvec_states state)
+static inline int dccp_ackvec_set_buf_head_state(struct dccp_ackvec *av,
+ const unsigned int packets,
+ const unsigned char state)
{
- u16 ptr = av->av_buf_head;
+ unsigned int gap;
+ long new_head;
- BUG_ON(distance > 0);
- if (unlikely(dccp_ackvec_is_empty(av)))
- return;
+ if (av->av_vec_len + packets > DCCP_MAX_ACKVEC_LEN)
+ return -ENOBUFS;
- do {
- u8 runlen = dccp_ackvec_runlen(av->av_buf + ptr);
+ gap = packets - 1;
+ new_head = av->av_buf_head - packets;
- if (distance + runlen >= 0) {
- /*
- * Only update the state if packet has not been received
- * yet. This is OK as per the second table in RFC 4340,
- * 11.4.1; i.e. here we are using the following table:
- * RECEIVED
- * 0 1 3
- * S +---+---+---+
- * T 0 | 0 | 0 | 0 |
- * O +---+---+---+
- * R 1 | 1 | 1 | 1 |
- * E +---+---+---+
- * D 3 | 0 | 1 | 3 |
- * +---+---+---+
- * The "Not Received" state was set by reserve_seats().
- */
- if (av->av_buf[ptr] == DCCPAV_NOT_RECEIVED)
- av->av_buf[ptr] = state;
- else
- dccp_pr_debug("Not changing %llu state to %u\n",
- (unsigned long long)seqno, state);
- break;
+ if (new_head < 0) {
+ if (gap > 0) {
+ memset(av->av_buf, DCCP_ACKVEC_STATE_NOT_RECEIVED,
+ gap + new_head + 1);
+ gap = -new_head;
}
+ new_head += DCCP_MAX_ACKVEC_LEN;
+ }
- distance += runlen + 1;
- ptr = __ackvec_idx_add(ptr, 1);
+ av->av_buf_head = new_head;
- } while (ptr != av->av_buf_tail);
-}
+ if (gap > 0)
+ memset(av->av_buf + av->av_buf_head + 1,
+ DCCP_ACKVEC_STATE_NOT_RECEIVED, gap);
-/* Mark @num entries after buf_head as "Not yet received". */
-static void dccp_ackvec_reserve_seats(struct dccp_ackvec *av, u16 num)
-{
- u16 start = __ackvec_idx_add(av->av_buf_head, 1),
- len = DCCPAV_MAX_ACKVEC_LEN - start;
-
- /* check for buffer wrap-around */
- if (num > len) {
- memset(av->av_buf + start, DCCPAV_NOT_RECEIVED, len);
- start = 0;
- num -= len;
- }
- if (num)
- memset(av->av_buf + start, DCCPAV_NOT_RECEIVED, num);
+ av->av_buf[av->av_buf_head] = state;
+ av->av_vec_len += packets;
+ return 0;
}
-/**
- * dccp_ackvec_add_new - Record one or more new entries in Ack Vector buffer
- * @av: container of buffer to update (can be empty or non-empty)
- * @num_packets: number of packets to register (must be >= 1)
- * @seqno: sequence number of the first packet in @num_packets
- * @state: state in which packet carrying @seqno was received
+/*
+ * Implements the RFC 4340, Appendix A
*/
-static void dccp_ackvec_add_new(struct dccp_ackvec *av, u32 num_packets,
- u64 seqno, enum dccp_ackvec_states state)
+int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+ const u64 ackno, const u8 state)
{
- u32 num_cells = num_packets;
+ /*
+ * Check at the right places if the buffer is full, if it is, tell the
+ * caller to start dropping packets till the HC-Sender acks our ACK
+ * vectors, when we will free up space in av_buf.
+ *
+ * We may well decide to do buffer compression, etc, but for now lets
+ * just drop.
+ *
+ * From Appendix A.1.1 (`New Packets'):
+ *
+ * Of course, the circular buffer may overflow, either when the
+ * HC-Sender is sending data at a very high rate, when the
+ * HC-Receiver's acknowledgements are not reaching the HC-Sender,
+ * or when the HC-Sender is forgetting to acknowledge those acks
+ * (so the HC-Receiver is unable to clean up old state). In this
+ * case, the HC-Receiver should either compress the buffer (by
+ * increasing run lengths when possible), transfer its state to
+ * a larger buffer, or, as a last resort, drop all received
+ * packets, without processing them whatsoever, until its buffer
+ * shrinks again.
+ */
- if (num_packets > DCCPAV_BURST_THRESH) {
- u32 lost_packets = num_packets - 1;
+ /* See if this is the first ackno being inserted */
+ if (av->av_vec_len == 0) {
+ av->av_buf[av->av_buf_head] = state;
+ av->av_vec_len = 1;
+ } else if (after48(ackno, av->av_buf_ackno)) {
+ const u64 delta = dccp_delta_seqno(av->av_buf_ackno, ackno);
- DCCP_WARN("Warning: large burst loss (%u)\n", lost_packets);
/*
- * We received 1 packet and have a loss of size "num_packets-1"
- * which we squeeze into num_cells-1 rather than reserving an
- * entire byte for each lost packet.
- * The reason is that the vector grows in O(burst_length); when
- * it grows too large there will no room left for the payload.
- * This is a trade-off: if a few packets out of the burst show
- * up later, their state will not be changed; it is simply too
- * costly to reshuffle/reallocate/copy the buffer each time.
- * Should such problems persist, we will need to switch to a
- * different underlying data structure.
+ * Look if the state of this packet is the same as the
+ * previous ackno and if so if we can bump the head len.
*/
- for (num_packets = num_cells = 1; lost_packets; ++num_cells) {
- u8 len = min(lost_packets, (u32)DCCPAV_MAX_RUNLEN);
-
- av->av_buf_head = __ackvec_idx_sub(av->av_buf_head, 1);
- av->av_buf[av->av_buf_head] = DCCPAV_NOT_RECEIVED | len;
+ if (delta == 1 &&
+ dccp_ackvec_state(av, av->av_buf_head) == state &&
+ dccp_ackvec_len(av, av->av_buf_head) < DCCP_ACKVEC_LEN_MASK)
+ av->av_buf[av->av_buf_head]++;
+ else if (dccp_ackvec_set_buf_head_state(av, delta, state))
+ return -ENOBUFS;
+ } else {
+ /*
+ * A.1.2. Old Packets
+ *
+ * When a packet with Sequence Number S <= buf_ackno
+ * arrives, the HC-Receiver will scan the table for
+ * the byte corresponding to S. (Indexing structures
+ * could reduce the complexity of this scan.)
+ */
+ u64 delta = dccp_delta_seqno(ackno, av->av_buf_ackno);
+ u32 index = av->av_buf_head;
- lost_packets -= len;
+ while (1) {
+ const u8 len = dccp_ackvec_len(av, index);
+ const u8 av_state = dccp_ackvec_state(av, index);
+ /*
+ * valid packets not yet in av_buf have a reserved
+ * entry, with a len equal to 0.
+ */
+ if (av_state == DCCP_ACKVEC_STATE_NOT_RECEIVED &&
+ len == 0 && delta == 0) { /* Found our
+ reserved seat! */
+ dccp_pr_debug("Found %llu reserved seat!\n",
+ (unsigned long long)ackno);
+ av->av_buf[index] = state;
+ goto out;
+ }
+ /* len == 0 means one packet */
+ if (delta < len + 1)
+ goto out_duplicate;
+
+ delta -= len + 1;
+ if (++index == DCCP_MAX_ACKVEC_LEN)
+ index = 0;
}
}
- if (num_cells + dccp_ackvec_buflen(av) >= DCCPAV_MAX_ACKVEC_LEN) {
- DCCP_CRIT("Ack Vector buffer overflow: dropping old entries\n");
- av->av_overflow = true;
- }
-
- av->av_buf_head = __ackvec_idx_sub(av->av_buf_head, num_packets);
- if (av->av_overflow)
- av->av_buf_tail = av->av_buf_head;
-
- av->av_buf[av->av_buf_head] = state;
- av->av_buf_ackno = seqno;
+ av->av_buf_ackno = ackno;
+ av->av_time = ktime_get_real();
+out:
+ return 0;
- if (num_packets > 1)
- dccp_ackvec_reserve_seats(av, num_packets - 1);
+out_duplicate:
+ /* Duplicate packet */
+ dccp_pr_debug("Received a dup or already considered lost "
+ "packet: %llu\n", (unsigned long long)ackno);
+ return -EILSEQ;
}
-/**
- * dccp_ackvec_input - Register incoming packet in the buffer
- */
-void dccp_ackvec_input(struct dccp_ackvec *av, struct sk_buff *skb)
+static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
+ struct dccp_ackvec_record *avr)
{
- u64 seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- enum dccp_ackvec_states state = DCCPAV_RECEIVED;
+ struct dccp_ackvec_record *next;
- if (dccp_ackvec_is_empty(av)) {
- dccp_ackvec_add_new(av, 1, seqno, state);
- av->av_tail_ackno = seqno;
+ /* sort out vector length */
+ if (av->av_buf_head <= avr->avr_ack_ptr)
+ av->av_vec_len = avr->avr_ack_ptr - av->av_buf_head;
+ else
+ av->av_vec_len = DCCP_MAX_ACKVEC_LEN - 1 -
+ av->av_buf_head + avr->avr_ack_ptr;
- } else {
- s64 num_packets = dccp_delta_seqno(av->av_buf_ackno, seqno);
- u8 *current_head = av->av_buf + av->av_buf_head;
-
- if (num_packets == 1 &&
- dccp_ackvec_state(current_head) == state &&
- dccp_ackvec_runlen(current_head) < DCCPAV_MAX_RUNLEN) {
+ /* free records */
+ list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
+ list_del_init(&avr->avr_node);
+ dccp_ackvec_record_delete(avr);
+ }
+}
- *current_head += 1;
- av->av_buf_ackno = seqno;
+void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av, struct sock *sk,
+ const u64 ackno)
+{
+ struct dccp_ackvec_record *avr;
- } else if (num_packets > 0) {
- dccp_ackvec_add_new(av, num_packets, seqno, state);
- } else {
- dccp_ackvec_update_old(av, num_packets, seqno, state);
- }
+ /*
+ * If we traverse backwards, it should be faster when we have large
+ * windows. We will be receiving ACKs for stuff we sent a while back
+ * -sorbo.
+ */
+ list_for_each_entry_reverse(avr, &av->av_records, avr_node) {
+ if (ackno == avr->avr_ack_seqno) {
+ dccp_pr_debug("%s ACK packet 0, len=%d, ack_seqno=%llu, "
+ "ack_ackno=%llu, ACKED!\n",
+ dccp_role(sk), 1,
+ (unsigned long long)avr->avr_ack_seqno,
+ (unsigned long long)avr->avr_ack_ackno);
+ dccp_ackvec_throw_record(av, avr);
+ break;
+ } else if (avr->avr_ack_seqno > ackno)
+ break; /* old news */
}
}
-/**
- * dccp_ackvec_clear_state - Perform house-keeping / garbage-collection
- * This routine is called when the peer acknowledges the receipt of Ack Vectors
- * up to and including @ackno. While based on on section A.3 of RFC 4340, here
- * are additional precautions to prevent corrupted buffer state. In particular,
- * we use tail_ackno to identify outdated records; it always marks the earliest
- * packet of group (2) in 11.4.2.
- */
-void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno)
- {
- struct dccp_ackvec_record *avr, *next;
- u8 runlen_now, eff_runlen;
- s64 delta;
+static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
+ struct sock *sk, u64 *ackno,
+ const unsigned char len,
+ const unsigned char *vector)
+{
+ unsigned char i;
+ struct dccp_ackvec_record *avr;
- avr = dccp_ackvec_lookup(&av->av_records, ackno);
- if (avr == NULL)
+ /* Check if we actually sent an ACK vector */
+ if (list_empty(&av->av_records))
return;
- /*
- * Deal with outdated acknowledgments: this arises when e.g. there are
- * several old records and the acks from the peer come in slowly. In
- * that case we may still have records that pre-date tail_ackno.
- */
- delta = dccp_delta_seqno(av->av_tail_ackno, avr->avr_ack_ackno);
- if (delta < 0)
- goto free_records;
- /*
- * Deal with overlapping Ack Vectors: don't subtract more than the
- * number of packets between tail_ackno and ack_ackno.
- */
- eff_runlen = delta < avr->avr_ack_runlen ? delta : avr->avr_ack_runlen;
- runlen_now = dccp_ackvec_runlen(av->av_buf + avr->avr_ack_ptr);
+ i = len;
/*
- * The run length of Ack Vector cells does not decrease over time. If
- * the run length is the same as at the time the Ack Vector was sent, we
- * free the ack_ptr cell. That cell can however not be freed if the run
- * length has increased: in this case we need to move the tail pointer
- * backwards (towards higher indices), to its next-oldest neighbour.
+ * XXX
+ * I think it might be more efficient to work backwards. See comment on
+ * rcv_ackno. -sorbo.
*/
- if (runlen_now > eff_runlen) {
+ avr = list_entry(av->av_records.next, struct dccp_ackvec_record, avr_node);
+ while (i--) {
+ const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
+ u64 ackno_end_rl;
- av->av_buf[avr->avr_ack_ptr] -= eff_runlen + 1;
- av->av_buf_tail = __ackvec_idx_add(avr->avr_ack_ptr, 1);
+ dccp_set_seqno(&ackno_end_rl, *ackno - rl);
- /* This move may not have cleared the overflow flag. */
- if (av->av_overflow)
- av->av_overflow = (av->av_buf_head == av->av_buf_tail);
- } else {
- av->av_buf_tail = avr->avr_ack_ptr;
/*
- * We have made sure that avr points to a valid cell within the
- * buffer. This cell is either older than head, or equals head
- * (empty buffer): in both cases we no longer have any overflow.
+ * If our AVR sequence number is greater than the ack, go
+ * forward in the AVR list until it is not so.
*/
- av->av_overflow = 0;
- }
-
- /*
- * The peer has acknowledged up to and including ack_ackno. Hence the
- * first packet in group (2) of 11.4.2 is the successor of ack_ackno.
- */
- av->av_tail_ackno = ADD48(avr->avr_ack_ackno, 1);
+ list_for_each_entry_from(avr, &av->av_records, avr_node) {
+ if (!after48(avr->avr_ack_seqno, *ackno))
+ goto found;
+ }
+ /* End of the av_records list, not found, exit */
+ break;
+found:
+ if (between48(avr->avr_ack_seqno, ackno_end_rl, *ackno)) {
+ const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
+ if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
+ dccp_pr_debug("%s ACK vector 0, len=%d, "
+ "ack_seqno=%llu, ack_ackno=%llu, "
+ "ACKED!\n",
+ dccp_role(sk), len,
+ (unsigned long long)
+ avr->avr_ack_seqno,
+ (unsigned long long)
+ avr->avr_ack_ackno);
+ dccp_ackvec_throw_record(av, avr);
+ break;
+ }
+ /*
+ * If it wasn't received, continue scanning... we might
+ * find another one.
+ */
+ }
-free_records:
- list_for_each_entry_safe_from(avr, next, &av->av_records, avr_node) {
- list_del(&avr->avr_node);
- kmem_cache_free(dccp_ackvec_record_slab, avr);
+ dccp_set_seqno(ackno, ackno_end_rl - 1);
+ ++vector;
}
}
-/*
- * Routines to keep track of Ack Vectors received in an skb
- */
-int dccp_ackvec_parsed_add(struct list_head *head, u8 *vec, u8 len, u8 nonce)
+int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+ u64 *ackno, const u8 opt, const u8 *value, const u8 len)
{
- struct dccp_ackvec_parsed *new = kmalloc(sizeof(*new), GFP_ATOMIC);
-
- if (new == NULL)
- return -ENOBUFS;
- new->vec = vec;
- new->len = len;
- new->nonce = nonce;
+ if (len > DCCP_MAX_ACKVEC_OPT_LEN)
+ return -1;
- list_add_tail(&new->node, head);
+ /* dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq, value, len); */
+ dccp_ackvec_check_rcv_ackvector(dccp_sk(sk)->dccps_hc_rx_ackvec, sk,
+ ackno, len, value);
return 0;
}
-EXPORT_SYMBOL_GPL(dccp_ackvec_parsed_add);
-
-void dccp_ackvec_parsed_cleanup(struct list_head *parsed_chunks)
-{
- struct dccp_ackvec_parsed *cur, *next;
-
- list_for_each_entry_safe(cur, next, parsed_chunks, node)
- kfree(cur);
- INIT_LIST_HEAD(parsed_chunks);
-}
-EXPORT_SYMBOL_GPL(dccp_ackvec_parsed_cleanup);
int __init dccp_ackvec_init(void)
{
if (dccp_ackvec_slab == NULL)
goto out_err;
- dccp_ackvec_record_slab = kmem_cache_create("dccp_ackvec_record",
- sizeof(struct dccp_ackvec_record),
- 0, SLAB_HWCACHE_ALIGN, NULL);
+ dccp_ackvec_record_slab =
+ kmem_cache_create("dccp_ackvec_record",
+ sizeof(struct dccp_ackvec_record),
+ 0, SLAB_HWCACHE_ALIGN, NULL);
if (dccp_ackvec_record_slab == NULL)
goto out_destroy_slab;
/*
* net/dccp/ackvec.h
*
- * An implementation of Ack Vectors for the DCCP protocol
- * Copyright (c) 2007 University of Aberdeen, Scotland, UK
+ * An implementation of the DCCP protocol
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
+ *
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
-#include <linux/dccp.h>
#include <linux/compiler.h>
+#include <linux/ktime.h>
#include <linux/list.h>
#include <linux/types.h>
-/*
- * Ack Vector buffer space is static, in multiples of %DCCP_SINGLE_OPT_MAXLEN,
- * the maximum size of a single Ack Vector. Setting %DCCPAV_NUM_ACKVECS to 1
- * will be sufficient for most cases of low Ack Ratios, using a value of 2 gives
- * more headroom if Ack Ratio is higher or when the sender acknowledges slowly.
- * The maximum value is bounded by the u16 types for indices and functions.
- */
-#define DCCPAV_NUM_ACKVECS 2
-#define DCCPAV_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * DCCPAV_NUM_ACKVECS)
-
-/* Estimated minimum average Ack Vector length - used for updating MPS */
-#define DCCPAV_MIN_OPTLEN 16
-
-/* Threshold for coping with large bursts of losses */
-#define DCCPAV_BURST_THRESH (DCCPAV_MAX_ACKVEC_LEN / 8)
-
-enum dccp_ackvec_states {
- DCCPAV_RECEIVED = 0x00,
- DCCPAV_ECN_MARKED = 0x40,
- DCCPAV_RESERVED = 0x80,
- DCCPAV_NOT_RECEIVED = 0xC0
-};
-#define DCCPAV_MAX_RUNLEN 0x3F
+/* Read about the ECN nonce to see why it is 253 */
+#define DCCP_MAX_ACKVEC_OPT_LEN 253
+/* We can spread an ack vector across multiple options */
+#define DCCP_MAX_ACKVEC_LEN (DCCP_MAX_ACKVEC_OPT_LEN * 2)
-static inline u8 dccp_ackvec_runlen(const u8 *cell)
-{
- return *cell & DCCPAV_MAX_RUNLEN;
-}
+#define DCCP_ACKVEC_STATE_RECEIVED 0
+#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
+#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
-static inline u8 dccp_ackvec_state(const u8 *cell)
-{
- return *cell & ~DCCPAV_MAX_RUNLEN;
-}
+#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */
+#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */
-/** struct dccp_ackvec - Ack Vector main data structure
+/** struct dccp_ackvec - ack vector
+ *
+ * This data structure is the one defined in RFC 4340, Appendix A.
*
- * This implements a fixed-size circular buffer within an array and is largely
- * based on Appendix A of RFC 4340.
+ * @av_buf_head - circular buffer head
+ * @av_buf_tail - circular buffer tail
+ * @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
+ * buffer (i.e. %av_buf_head)
+ * @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
+ * by the buffer with State 0
*
- * @av_buf: circular buffer storage area
- * @av_buf_head: head index; begin of live portion in @av_buf
- * @av_buf_tail: tail index; first index _after_ the live portion in @av_buf
- * @av_buf_ackno: highest seqno of acknowledgeable packet recorded in @av_buf
- * @av_tail_ackno: lowest seqno of acknowledgeable packet recorded in @av_buf
- * @av_buf_nonce: ECN nonce sums, each covering subsequent segments of up to
- * %DCCP_SINGLE_OPT_MAXLEN cells in the live portion of @av_buf
- * @av_overflow: if 1 then buf_head == buf_tail indicates buffer wraparound
- * @av_records: list of %dccp_ackvec_record (Ack Vectors sent previously)
+ * Additionally, the HC-Receiver must keep some information about the
+ * Ack Vectors it has recently sent. For each packet sent carrying an
+ * Ack Vector, it remembers four variables:
+ *
+ * @av_records - list of dccp_ackvec_record
+ * @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
+ *
+ * @av_time - the time in usecs
+ * @av_buf - circular buffer of acknowledgeable packets
*/
struct dccp_ackvec {
- u8 av_buf[DCCPAV_MAX_ACKVEC_LEN];
- u16 av_buf_head;
- u16 av_buf_tail;
- u64 av_buf_ackno:48;
- u64 av_tail_ackno:48;
- bool av_buf_nonce[DCCPAV_NUM_ACKVECS];
- u8 av_overflow:1;
+ u64 av_buf_ackno;
struct list_head av_records;
+ ktime_t av_time;
+ u16 av_buf_head;
+ u16 av_vec_len;
+ u8 av_buf_nonce;
+ u8 av_ack_nonce;
+ u8 av_buf[DCCP_MAX_ACKVEC_LEN];
};
-/** struct dccp_ackvec_record - Records information about sent Ack Vectors
+/** struct dccp_ackvec_record - ack vector record
*
- * These list entries define the additional information which the HC-Receiver
- * keeps about recently-sent Ack Vectors; again refer to RFC 4340, Appendix A.
+ * ACK vector record as defined in Appendix A of spec.
*
- * @avr_node: the list node in @av_records
- * @avr_ack_seqno: sequence number of the packet the Ack Vector was sent on
- * @avr_ack_ackno: the Ack number that this record/Ack Vector refers to
- * @avr_ack_ptr: pointer into @av_buf where this record starts
- * @avr_ack_runlen: run length of @avr_ack_ptr at the time of sending
- * @avr_ack_nonce: the sum of @av_buf_nonce's at the time this record was sent
+ * The list is sorted by avr_ack_seqno
*
- * The list as a whole is sorted in descending order by @avr_ack_seqno.
+ * @avr_node - node in av_records
+ * @avr_ack_seqno - sequence number of the packet this record was sent on
+ * @avr_ack_ackno - sequence number being acknowledged
+ * @avr_ack_ptr - pointer into av_buf where this record starts
+ * @avr_ack_nonce - av_ack_nonce at the time this record was sent
+ * @avr_sent_len - lenght of the record in av_buf
*/
struct dccp_ackvec_record {
struct list_head avr_node;
- u64 avr_ack_seqno:48;
- u64 avr_ack_ackno:48;
+ u64 avr_ack_seqno;
+ u64 avr_ack_ackno;
u16 avr_ack_ptr;
- u8 avr_ack_runlen;
- u8 avr_ack_nonce:1;
+ u16 avr_sent_len;
+ u8 avr_ack_nonce;
};
-extern int dccp_ackvec_init(void);
+struct sock;
+struct sk_buff;
+
+#ifdef CONFIG_IP_DCCP_ACKVEC
+extern int dccp_ackvec_init(void);
extern void dccp_ackvec_exit(void);
extern struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority);
extern void dccp_ackvec_free(struct dccp_ackvec *av);
-extern void dccp_ackvec_input(struct dccp_ackvec *av, struct sk_buff *skb);
-extern int dccp_ackvec_update_records(struct dccp_ackvec *av, u64 seq, u8 sum);
-extern void dccp_ackvec_clear_state(struct dccp_ackvec *av, const u64 ackno);
-extern u16 dccp_ackvec_buflen(const struct dccp_ackvec *av);
+extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+ const u64 ackno, const u8 state);
+
+extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
+ struct sock *sk, const u64 ackno);
+extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+ u64 *ackno, const u8 opt,
+ const u8 *value, const u8 len);
-static inline bool dccp_ackvec_is_empty(const struct dccp_ackvec *av)
+extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
+
+static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
+{
+ return av->av_vec_len;
+}
+#else /* CONFIG_IP_DCCP_ACKVEC */
+static inline int dccp_ackvec_init(void)
{
- return av->av_overflow == 0 && av->av_buf_head == av->av_buf_tail;
+ return 0;
}
-/**
- * struct dccp_ackvec_parsed - Record offsets of Ack Vectors in skb
- * @vec: start of vector (offset into skb)
- * @len: length of @vec
- * @nonce: whether @vec had an ECN nonce of 0 or 1
- * @node: FIFO - arranged in descending order of ack_ackno
- * This structure is used by CCIDs to access Ack Vectors in a received skb.
- */
-struct dccp_ackvec_parsed {
- u8 *vec,
- len,
- nonce:1;
- struct list_head node;
-};
+static inline void dccp_ackvec_exit(void)
+{
+}
+
+static inline struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
+{
+ return NULL;
+}
+
+static inline void dccp_ackvec_free(struct dccp_ackvec *av)
+{
+}
+
+static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
+ const u64 ackno, const u8 state)
+{
+ return -1;
+}
-extern int dccp_ackvec_parsed_add(struct list_head *head,
- u8 *vec, u8 len, u8 nonce);
-extern void dccp_ackvec_parsed_cleanup(struct list_head *parsed_chunks);
+static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
+ struct sock *sk, const u64 ackno)
+{
+}
+
+static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
+ const u64 *ackno, const u8 opt,
+ const u8 *value, const u8 len)
+{
+ return -1;
+}
+
+static inline int dccp_insert_option_ackvec(const struct sock *sk,
+ const struct sk_buff *skb)
+{
+ return -1;
+}
+
+static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
+{
+ return 0;
+}
+#endif /* CONFIG_IP_DCCP_ACKVEC */
#endif /* _ACKVEC_H */
#include "ccid.h"
-static u8 builtin_ccids[] = {
- DCCPC_CCID2, /* CCID2 is supported by default */
-#if defined(CONFIG_IP_DCCP_CCID3) || defined(CONFIG_IP_DCCP_CCID3_MODULE)
- DCCPC_CCID3,
-#endif
-};
-
static struct ccid_operations *ccids[CCID_MAX];
#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
static atomic_t ccids_lockct = ATOMIC_INIT(0);
}
}
-/* check that up to @array_len members in @ccid_array are supported */
-bool ccid_support_check(u8 const *ccid_array, u8 array_len)
-{
- u8 i, j, found;
-
- for (i = 0, found = 0; i < array_len; i++, found = 0) {
- for (j = 0; !found && j < ARRAY_SIZE(builtin_ccids); j++)
- found = (ccid_array[i] == builtin_ccids[j]);
- if (!found)
- return false;
- }
- return true;
-}
-
-/**
- * ccid_get_builtin_ccids - Provide copy of `builtin' CCID array
- * @ccid_array: pointer to copy into
- * @array_len: value to return length into
- * This function allocates memory - caller must see that it is freed after use.
- */
-int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len)
-{
- *ccid_array = kmemdup(builtin_ccids, sizeof(builtin_ccids), gfp_any());
- if (*ccid_array == NULL)
- return -ENOBUFS;
- *array_len = ARRAY_SIZE(builtin_ccids);
- return 0;
-}
-
-int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
- char __user *optval, int __user *optlen)
-{
- if (len < sizeof(builtin_ccids))
- return -EINVAL;
-
- if (put_user(sizeof(builtin_ccids), optlen) ||
- copy_to_user(optval, builtin_ccids, sizeof(builtin_ccids)))
- return -EFAULT;
- return 0;
-}
-
int ccid_register(struct ccid_operations *ccid_ops)
{
int err = -ENOBUFS;
EXPORT_SYMBOL_GPL(ccid_unregister);
-/**
- * ccid_request_module - Pre-load CCID module for later use
- * This should be called only from process context (e.g. during connection
- * setup) and is necessary for later calls to ccid_new (typically in software
- * interrupt), so that it has the modules available when they are needed.
- */
-static int ccid_request_module(u8 id)
-{
- if (!in_atomic()) {
- ccids_read_lock();
- if (ccids[id] == NULL) {
- ccids_read_unlock();
- return request_module("net-dccp-ccid-%d", id);
- }
- ccids_read_unlock();
- }
- return 0;
-}
-
-int ccid_request_modules(u8 const *ccid_array, u8 array_len)
-{
-#ifdef CONFIG_KMOD
- while (array_len--)
- if (ccid_request_module(ccid_array[array_len]))
- return -1;
-#endif
- return 0;
-}
-
struct ccid *ccid_new(unsigned char id, struct sock *sk, int rx, gfp_t gfp)
{
struct ccid_operations *ccid_ops;
struct ccid *ccid = NULL;
ccids_read_lock();
+#ifdef CONFIG_KMOD
+ if (ccids[id] == NULL) {
+ /* We only try to load if in process context */
+ ccids_read_unlock();
+ if (gfp & GFP_ATOMIC)
+ goto out;
+ request_module("net-dccp-ccid-%d", id);
+ ccids_read_lock();
+ }
+#endif
ccid_ops = ccids[id];
if (ccid_ops == NULL)
goto out_unlock;
EXPORT_SYMBOL_GPL(ccid_new);
+struct ccid *ccid_hc_rx_new(unsigned char id, struct sock *sk, gfp_t gfp)
+{
+ return ccid_new(id, sk, 1, gfp);
+}
+
+EXPORT_SYMBOL_GPL(ccid_hc_rx_new);
+
+struct ccid *ccid_hc_tx_new(unsigned char id,struct sock *sk, gfp_t gfp)
+{
+ return ccid_new(id, sk, 0, gfp);
+}
+
+EXPORT_SYMBOL_GPL(ccid_hc_tx_new);
+
static void ccid_delete(struct ccid *ccid, struct sock *sk, int rx)
{
struct ccid_operations *ccid_ops;
void (*ccid_hc_tx_exit)(struct sock *sk);
void (*ccid_hc_rx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
- int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt,
- u8 opt, u8 *val, u8 len);
+ int (*ccid_hc_rx_parse_options)(struct sock *sk,
+ unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char* value);
int (*ccid_hc_rx_insert_options)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
- int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt,
- u8 opt, u8 *val, u8 len);
+ int (*ccid_hc_tx_parse_options)(struct sock *sk,
+ unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char* value);
int (*ccid_hc_tx_send_packet)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_sent)(struct sock *sk,
- unsigned int len);
+ int more, unsigned int len);
void (*ccid_hc_rx_get_info)(struct sock *sk,
struct tcp_info *info);
void (*ccid_hc_tx_get_info)(struct sock *sk,
return (void *)ccid->ccid_priv;
}
-extern bool ccid_support_check(u8 const *ccid_array, u8 array_len);
-extern int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
-extern int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
- char __user *, int __user *);
-
-extern int ccid_request_modules(u8 const *ccid_array, u8 array_len);
extern struct ccid *ccid_new(unsigned char id, struct sock *sk, int rx,
gfp_t gfp);
-static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
-{
- struct ccid *ccid = dp->dccps_hc_rx_ccid;
-
- if (ccid == NULL || ccid->ccid_ops == NULL)
- return -1;
- return ccid->ccid_ops->ccid_id;
-}
-
-static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
-{
- struct ccid *ccid = dp->dccps_hc_tx_ccid;
-
- if (ccid == NULL || ccid->ccid_ops == NULL)
- return -1;
- return ccid->ccid_ops->ccid_id;
-}
+extern struct ccid *ccid_hc_rx_new(unsigned char id, struct sock *sk,
+ gfp_t gfp);
+extern struct ccid *ccid_hc_tx_new(unsigned char id, struct sock *sk,
+ gfp_t gfp);
extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
-/*
- * Congestion control of queued data packets via CCID decision.
- *
- * The TX CCID performs its congestion-control by indicating whether and when a
- * queued packet may be sent, using the return code of ccid_hc_tx_send_packet().
- * The following modes are supported via the symbolic constants below:
- * - timer-based pacing (CCID returns a delay value in milliseconds);
- * - autonomous dequeueing (CCID internally schedules dccps_xmitlet).
- */
-
-enum ccid_dequeueing_decision {
- CCID_PACKET_SEND_AT_ONCE = 0x00000, /* "green light": no delay */
- CCID_PACKET_DELAY_MAX = 0x0FFFF, /* maximum delay in msecs */
- CCID_PACKET_DELAY = 0x10000, /* CCID msec-delay mode */
- CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000, /* CCID autonomous mode */
- CCID_PACKET_ERR = 0xF0000, /* error condition */
-};
-
-static inline int ccid_packet_dequeue_eval(const int return_code)
-{
- if (return_code < 0)
- return CCID_PACKET_ERR;
- if (return_code == 0)
- return CCID_PACKET_SEND_AT_ONCE;
- if (return_code <= CCID_PACKET_DELAY_MAX)
- return CCID_PACKET_DELAY;
- return return_code;
-}
-
static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb)
{
+ int rc = 0;
if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
- return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
- return CCID_PACKET_SEND_AT_ONCE;
+ rc = ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
+ return rc;
}
static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
- unsigned int len)
+ int more, unsigned int len)
{
if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
- ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len);
+ ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, more, len);
}
static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
}
-/**
- * ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver
- * @pkt: type of packet that @opt appears on (RFC 4340, 5.1)
- * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3)
- * @val: value of @opt
- * @len: length of @val in bytes
- */
static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
- u8 pkt, u8 opt, u8 *val, u8 len)
+ unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char* value)
{
- if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL)
- return 0;
- return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len);
+ int rc = 0;
+ if (ccid->ccid_ops->ccid_hc_tx_parse_options != NULL)
+ rc = ccid->ccid_ops->ccid_hc_tx_parse_options(sk, option, len, idx,
+ value);
+ return rc;
}
-/**
- * ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender
- * Arguments are analogous to ccid_hc_tx_parse_options()
- */
static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
- u8 pkt, u8 opt, u8 *val, u8 len)
+ unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char* value)
{
- if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL)
- return 0;
- return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len);
+ int rc = 0;
+ if (ccid->ccid_ops->ccid_hc_rx_parse_options != NULL)
+ rc = ccid->ccid_ops->ccid_hc_rx_parse_options(sk, option, len, idx, value);
+ return rc;
}
static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
menu "DCCP CCIDs Configuration (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
config IP_DCCP_CCID2
- tristate "CCID2 (TCP-Like)"
+ tristate "CCID2 (TCP-Like) (EXPERIMENTAL)"
def_tristate IP_DCCP
+ select IP_DCCP_ACKVEC
---help---
CCID 2, TCP-like Congestion Control, denotes Additive Increase,
Multiplicative Decrease (AIMD) congestion control with behavior
If in doubt, say N.
config IP_DCCP_CCID3
- tristate "CCID3 (TCP-Friendly)"
+ tristate "CCID3 (TCP-Friendly) (EXPERIMENTAL)"
def_tristate IP_DCCP
select IP_DCCP_TFRC_LIB
---help---
If in doubt, say M.
-if IP_DCCP_CCID3
config IP_DCCP_CCID3_DEBUG
bool "CCID3 debugging messages"
+ depends on IP_DCCP_CCID3
---help---
Enable CCID3-specific debugging messages.
If in doubt, say N.
-choice
- prompt "Select method for measuring the packet size s"
- default IP_DCCP_CCID3_MEASURE_S_AS_MPS
-
-config IP_DCCP_CCID3_MEASURE_S_AS_MPS
- bool "Always use MPS in place of s"
- ---help---
- This use is recommended as it is consistent with the initialisation
- of X and suggested when s varies (rfc3448bis, (1) in section 4.1).
-config IP_DCCP_CCID3_MEASURE_S_AS_AVG
- bool "Use moving average"
- ---help---
- An alternative way of tracking s, also supported by rfc3448bis.
- This used to be the default for CCID-3 in previous kernels.
-config IP_DCCP_CCID3_MEASURE_S_AS_MAX
- bool "Track the maximum payload length"
- ---help---
- An experimental method based on tracking the maximum packet size.
-endchoice
-
config IP_DCCP_CCID3_RTO
int "Use higher bound for nofeedback timer"
default 100
+ depends on IP_DCCP_CCID3 && EXPERIMENTAL
---help---
Use higher lower bound for nofeedback timer expiration.
The purpose of the nofeedback timer is to slow DCCP down when there
is serious network congestion: experimenting with larger values should
therefore not be performed on WANs.
-endif # IP_DCCP_CCID3
config IP_DCCP_TFRC_LIB
tristate
/*
* This implementation should follow RFC 4341
*/
-#include "../feat.h"
+
#include "../ccid.h"
#include "../dccp.h"
#include "ccid2.h"
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
static int ccid2_debug;
#define ccid2_pr_debug(format, a...) DCCP_PR_DEBUG(ccid2_debug, format, ##a)
+
+static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx)
+{
+ int len = 0;
+ int pipe = 0;
+ struct ccid2_seq *seqp = hctx->ccid2hctx_seqh;
+
+ /* there is data in the chain */
+ if (seqp != hctx->ccid2hctx_seqt) {
+ seqp = seqp->ccid2s_prev;
+ len++;
+ if (!seqp->ccid2s_acked)
+ pipe++;
+
+ while (seqp != hctx->ccid2hctx_seqt) {
+ struct ccid2_seq *prev = seqp->ccid2s_prev;
+
+ len++;
+ if (!prev->ccid2s_acked)
+ pipe++;
+
+ /* packets are sent sequentially */
+ BUG_ON(dccp_delta_seqno(seqp->ccid2s_seq,
+ prev->ccid2s_seq ) >= 0);
+ BUG_ON(time_before(seqp->ccid2s_sent,
+ prev->ccid2s_sent));
+
+ seqp = prev;
+ }
+ }
+
+ BUG_ON(pipe != hctx->ccid2hctx_pipe);
+ ccid2_pr_debug("len of chain=%d\n", len);
+
+ do {
+ seqp = seqp->ccid2s_prev;
+ len++;
+ } while (seqp != hctx->ccid2hctx_seqh);
+
+ ccid2_pr_debug("total len=%d\n", len);
+ BUG_ON(len != hctx->ccid2hctx_seqbufc * CCID2_SEQBUF_LEN);
+}
#else
#define ccid2_pr_debug(format, a...)
+#define ccid2_hc_tx_check_sanity(hctx)
#endif
static int ccid2_hc_tx_alloc_seq(struct ccid2_hc_tx_sock *hctx)
int i;
/* check if we have space to preserve the pointer to the buffer */
- if (hctx->seqbufc >= sizeof(hctx->seqbuf) / sizeof(struct ccid2_seq *))
+ if (hctx->ccid2hctx_seqbufc >= (sizeof(hctx->ccid2hctx_seqbuf) /
+ sizeof(struct ccid2_seq*)))
return -ENOMEM;
/* allocate buffer and initialize linked list */
seqp->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
/* This is the first allocation. Initiate the head and tail. */
- if (hctx->seqbufc == 0)
- hctx->seqh = hctx->seqt = seqp;
+ if (hctx->ccid2hctx_seqbufc == 0)
+ hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqt = seqp;
else {
/* link the existing list with the one we just created */
- hctx->seqh->ccid2s_next = seqp;
- seqp->ccid2s_prev = hctx->seqh;
+ hctx->ccid2hctx_seqh->ccid2s_next = seqp;
+ seqp->ccid2s_prev = hctx->ccid2hctx_seqh;
- hctx->seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
- seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hctx->seqt;
+ hctx->ccid2hctx_seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1];
+ seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hctx->ccid2hctx_seqt;
}
/* store the original pointer to the buffer so we can free it */
- hctx->seqbuf[hctx->seqbufc] = seqp;
- hctx->seqbufc++;
+ hctx->ccid2hctx_seqbuf[hctx->ccid2hctx_seqbufc] = seqp;
+ hctx->ccid2hctx_seqbufc++;
return 0;
}
static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
- if (ccid2_cwnd_network_limited(ccid2_hc_tx_sk(sk)))
- return CCID_PACKET_WILL_DEQUEUE_LATER;
- return CCID_PACKET_SEND_AT_ONCE;
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+
+ if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd)
+ return 0;
+
+ return 1; /* XXX CCID should dequeue when ready instead of polling */
}
static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val)
{
struct dccp_sock *dp = dccp_sk(sk);
- u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->cwnd, 2);
+ u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->ccid2hctx_cwnd, 2);
/*
* Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from
DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio);
val = max_ratio;
}
- if (val > DCCPF_ACK_RATIO_MAX)
- val = DCCPF_ACK_RATIO_MAX;
+ if (val > 0xFFFF) /* RFC 4340, 11.3 */
+ val = 0xFFFF;
if (val == dp->dccps_l_ack_ratio)
return;
dp->dccps_l_ack_ratio = val;
}
+static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val)
+{
+ ccid2_pr_debug("change SRTT to %ld\n", val);
+ hctx->ccid2hctx_srtt = val;
+}
+
+static void ccid2_start_rto_timer(struct sock *sk);
+
static void ccid2_hc_tx_rto_expire(unsigned long data)
{
struct sock *sk = (struct sock *)data;
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- const bool sender_was_blocked = ccid2_cwnd_network_limited(hctx);
+ long s;
bh_lock_sock(sk);
if (sock_owned_by_user(sk)) {
- sk_reset_timer(sk, &hctx->rtotimer, jiffies + HZ / 5);
+ sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
+ jiffies + HZ / 5);
goto out;
}
ccid2_pr_debug("RTO_EXPIRE\n");
+ ccid2_hc_tx_check_sanity(hctx);
+
/* back-off timer */
- hctx->rto <<= 1;
- if (hctx->rto > DCCP_RTO_MAX)
- hctx->rto = DCCP_RTO_MAX;
+ hctx->ccid2hctx_rto <<= 1;
+
+ s = hctx->ccid2hctx_rto / HZ;
+ if (s > 60)
+ hctx->ccid2hctx_rto = 60 * HZ;
+
+ ccid2_start_rto_timer(sk);
/* adjust pipe, cwnd etc */
- hctx->ssthresh = hctx->cwnd / 2;
- if (hctx->ssthresh < 2)
- hctx->ssthresh = 2;
- hctx->cwnd = 1;
- hctx->pipe = 0;
+ hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd / 2;
+ if (hctx->ccid2hctx_ssthresh < 2)
+ hctx->ccid2hctx_ssthresh = 2;
+ hctx->ccid2hctx_cwnd = 1;
+ hctx->ccid2hctx_pipe = 0;
/* clear state about stuff we sent */
- hctx->seqt = hctx->seqh;
- hctx->packets_acked = 0;
+ hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh;
+ hctx->ccid2hctx_packets_acked = 0;
/* clear ack ratio state. */
- hctx->rpseq = 0;
- hctx->rpdupack = -1;
+ hctx->ccid2hctx_rpseq = 0;
+ hctx->ccid2hctx_rpdupack = -1;
ccid2_change_l_ack_ratio(sk, 1);
-
- /* if we were blocked before, we may now send cwnd=1 packet */
- if (sender_was_blocked)
- tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet);
- /* restart backed-off timer */
- sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
+ ccid2_hc_tx_check_sanity(hctx);
out:
bh_unlock_sock(sk);
sock_put(sk);
}
-static void ccid2_hc_tx_packet_sent(struct sock *sk, unsigned int len)
+static void ccid2_start_rto_timer(struct sock *sk)
+{
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+
+ ccid2_pr_debug("setting RTO timeout=%ld\n", hctx->ccid2hctx_rto);
+
+ BUG_ON(timer_pending(&hctx->ccid2hctx_rtotimer));
+ sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer,
+ jiffies + hctx->ccid2hctx_rto);
+}
+
+static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
struct ccid2_seq *next;
- hctx->pipe++;
+ hctx->ccid2hctx_pipe++;
- hctx->seqh->ccid2s_seq = dp->dccps_gss;
- hctx->seqh->ccid2s_acked = 0;
- hctx->seqh->ccid2s_sent = jiffies;
+ hctx->ccid2hctx_seqh->ccid2s_seq = dp->dccps_gss;
+ hctx->ccid2hctx_seqh->ccid2s_acked = 0;
+ hctx->ccid2hctx_seqh->ccid2s_sent = jiffies;
- next = hctx->seqh->ccid2s_next;
+ next = hctx->ccid2hctx_seqh->ccid2s_next;
/* check if we need to alloc more space */
- if (next == hctx->seqt) {
+ if (next == hctx->ccid2hctx_seqt) {
if (ccid2_hc_tx_alloc_seq(hctx)) {
DCCP_CRIT("packet history - out of memory!");
/* FIXME: find a more graceful way to bail out */
return;
}
- next = hctx->seqh->ccid2s_next;
- BUG_ON(next == hctx->seqt);
+ next = hctx->ccid2hctx_seqh->ccid2s_next;
+ BUG_ON(next == hctx->ccid2hctx_seqt);
}
- hctx->seqh = next;
+ hctx->ccid2hctx_seqh = next;
- ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->cwnd, hctx->pipe);
+ ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd,
+ hctx->ccid2hctx_pipe);
/*
* FIXME: The code below is broken and the variables have been removed
*/
#if 0
/* Ack Ratio. Need to maintain a concept of how many windows we sent */
- hctx->arsent++;
+ hctx->ccid2hctx_arsent++;
/* We had an ack loss in this window... */
- if (hctx->ackloss) {
- if (hctx->arsent >= hctx->cwnd) {
- hctx->arsent = 0;
- hctx->ackloss = 0;
+ if (hctx->ccid2hctx_ackloss) {
+ if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) {
+ hctx->ccid2hctx_arsent = 0;
+ hctx->ccid2hctx_ackloss = 0;
}
} else {
/* No acks lost up to now... */
int denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio -
dp->dccps_l_ack_ratio;
- denom = hctx->cwnd * hctx->cwnd / denom;
+ denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom;
- if (hctx->arsent >= denom) {
+ if (hctx->ccid2hctx_arsent >= denom) {
ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1);
- hctx->arsent = 0;
+ hctx->ccid2hctx_arsent = 0;
}
} else {
/* we can't increase ack ratio further [1] */
- hctx->arsent = 0; /* or maybe set it to cwnd*/
+ hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/
}
}
#endif
/* setup RTO timer */
- if (!timer_pending(&hctx->rtotimer))
- sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
+ if (!timer_pending(&hctx->ccid2hctx_rtotimer))
+ ccid2_start_rto_timer(sk);
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
do {
- struct ccid2_seq *seqp = hctx->seqt;
+ struct ccid2_seq *seqp = hctx->ccid2hctx_seqt;
- while (seqp != hctx->seqh) {
+ while (seqp != hctx->ccid2hctx_seqh) {
ccid2_pr_debug("out seq=%llu acked=%d time=%lu\n",
(unsigned long long)seqp->ccid2s_seq,
seqp->ccid2s_acked, seqp->ccid2s_sent);
}
} while (0);
ccid2_pr_debug("=========\n");
+ ccid2_hc_tx_check_sanity(hctx);
#endif
}
-/**
- * ccid2_rtt_estimator - Sample RTT and compute RTO using RFC2988 algorithm
- * This code is almost identical with TCP's tcp_rtt_estimator(), since
- * - it has a higher sampling frequency (recommended by RFC 1323),
- * - the RTO does not collapse into RTT due to RTTVAR going towards zero,
- * - it is simple (cf. more complex proposals such as Eifel timer or research
- * which suggests that the gain should be set according to window size),
- * - in tests it was found to work well with CCID2 [gerrit].
+/* XXX Lame code duplication!
+ * returns -1 if none was found.
+ * else returns the next offset to use in the function call.
*/
-static void ccid2_rtt_estimator(struct sock *sk, const long mrtt)
+static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset,
+ unsigned char **vec, unsigned char *veclen)
{
- struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- long m = mrtt ? : 1;
-
- if (hctx->srtt == 0) {
- /* First measurement m */
- hctx->srtt = m << 3;
- hctx->mdev = m << 1;
-
- hctx->mdev_max = max(TCP_RTO_MIN, hctx->mdev);
- hctx->rttvar = hctx->mdev_max;
- hctx->rtt_seq = dccp_sk(sk)->dccps_gss;
- } else {
- /* Update scaled SRTT as SRTT += 1/8 * (m - SRTT) */
- m -= (hctx->srtt >> 3);
- hctx->srtt += m;
-
- /* Similarly, update scaled mdev with regard to |m| */
- if (m < 0) {
- m = -m;
- m -= (hctx->mdev >> 2);
+ const struct dccp_hdr *dh = dccp_hdr(skb);
+ unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
+ unsigned char *opt_ptr;
+ const unsigned char *opt_end = (unsigned char *)dh +
+ (dh->dccph_doff * 4);
+ unsigned char opt, len;
+ unsigned char *value;
+
+ BUG_ON(offset < 0);
+ options += offset;
+ opt_ptr = options;
+ if (opt_ptr >= opt_end)
+ return -1;
+
+ while (opt_ptr != opt_end) {
+ opt = *opt_ptr++;
+ len = 0;
+ value = NULL;
+
+ /* Check if this isn't a single byte option */
+ if (opt > DCCPO_MAX_RESERVED) {
+ if (opt_ptr == opt_end)
+ goto out_invalid_option;
+
+ len = *opt_ptr++;
+ if (len < 3)
+ goto out_invalid_option;
/*
- * This neutralises RTO increase when RTT < SRTT - mdev
- * (see P. Sarolahti, A. Kuznetsov,"Congestion Control
- * in Linux TCP", USENIX 2002, pp. 49-62).
+ * Remove the type and len fields, leaving
+ * just the value size
*/
- if (m > 0)
- m >>= 3;
- } else {
- m -= (hctx->mdev >> 2);
- }
- hctx->mdev += m;
+ len -= 2;
+ value = opt_ptr;
+ opt_ptr += len;
- if (hctx->mdev > hctx->mdev_max) {
- hctx->mdev_max = hctx->mdev;
- if (hctx->mdev_max > hctx->rttvar)
- hctx->rttvar = hctx->mdev_max;
+ if (opt_ptr > opt_end)
+ goto out_invalid_option;
}
- /*
- * Decay RTTVAR at most once per flight, exploiting that
- * 1) pipe <= cwnd <= Sequence_Window = W (RFC 4340, 7.5.2)
- * 2) AWL = GSS-W+1 <= GAR <= GSS (RFC 4340, 7.5.1)
- * GAR is a useful bound for FlightSize = pipe, AWL is probably
- * too low as it over-estimates pipe.
- */
- if (after48(dccp_sk(sk)->dccps_gar, hctx->rtt_seq)) {
- if (hctx->mdev_max < hctx->rttvar)
- hctx->rttvar -= (hctx->rttvar -
- hctx->mdev_max) >> 2;
- hctx->rtt_seq = dccp_sk(sk)->dccps_gss;
- hctx->mdev_max = TCP_RTO_MIN;
+ switch (opt) {
+ case DCCPO_ACK_VECTOR_0:
+ case DCCPO_ACK_VECTOR_1:
+ *vec = value;
+ *veclen = len;
+ return offset + (opt_ptr - options);
}
}
- /*
- * Set RTO from SRTT and RTTVAR
- * Clock granularity is ignored since the minimum error for RTTVAR is
- * clamped to 50msec (corresponding to HZ=20). This leads to a minimum
- * RTO of 200msec. This agrees with TCP and RFC 4341, 5.: "Because DCCP
- * does not retransmit data, DCCP does not require TCP's recommended
- * minimum timeout of one second".
- */
- hctx->rto = (hctx->srtt >> 3) + hctx->rttvar;
+ return -1;
- if (hctx->rto > DCCP_RTO_MAX)
- hctx->rto = DCCP_RTO_MAX;
+out_invalid_option:
+ DCCP_BUG("Invalid option - this should not happen (previous parsing)!");
+ return -1;
}
-static void ccid2_new_ack(struct sock *sk, struct ccid2_seq *seqp,
- unsigned int *maxincr)
+static void ccid2_hc_tx_kill_rto_timer(struct sock *sk)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- if (hctx->cwnd < hctx->ssthresh) {
- if (*maxincr > 0 && ++hctx->packets_acked == 2) {
- hctx->cwnd += 1;
- *maxincr -= 1;
- hctx->packets_acked = 0;
- }
- } else if (++hctx->packets_acked >= hctx->cwnd) {
- hctx->cwnd += 1;
- hctx->packets_acked = 0;
- }
- /*
- * FIXME: RTT is sampled several times per acknowledgment (for each
- * entry in the Ack Vector), instead of once per Ack (as in TCP SACK).
- * This causes the RTT to be over-estimated, since the older entries
- * in the Ack Vector have earlier sending times.
- * The cleanest solution is to not use the ccid2s_sent field at all
- * and instead use DCCP timestamps - need to be resolved at some time.
- */
- ccid2_rtt_estimator(sk, jiffies - seqp->ccid2s_sent);
+ sk_stop_timer(sk, &hctx->ccid2hctx_rtotimer);
+ ccid2_pr_debug("deleted RTO timer\n");
}
-static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
+static inline void ccid2_new_ack(struct sock *sk,
+ struct ccid2_seq *seqp,
+ unsigned int *maxincr)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- if (time_before(seqp->ccid2s_sent, hctx->last_cong)) {
- ccid2_pr_debug("Multiple losses in an RTT---treating as one\n");
- return;
+ if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) {
+ if (*maxincr > 0 && ++hctx->ccid2hctx_packets_acked == 2) {
+ hctx->ccid2hctx_cwnd += 1;
+ *maxincr -= 1;
+ hctx->ccid2hctx_packets_acked = 0;
+ }
+ } else if (++hctx->ccid2hctx_packets_acked >= hctx->ccid2hctx_cwnd) {
+ hctx->ccid2hctx_cwnd += 1;
+ hctx->ccid2hctx_packets_acked = 0;
}
- hctx->last_cong = jiffies;
+ /* update RTO */
+ if (hctx->ccid2hctx_srtt == -1 ||
+ time_after(jiffies, hctx->ccid2hctx_lastrtt + hctx->ccid2hctx_srtt)) {
+ unsigned long r = (long)jiffies - (long)seqp->ccid2s_sent;
+ int s;
+
+ /* first measurement */
+ if (hctx->ccid2hctx_srtt == -1) {
+ ccid2_pr_debug("R: %lu Time=%lu seq=%llu\n",
+ r, jiffies,
+ (unsigned long long)seqp->ccid2s_seq);
+ ccid2_change_srtt(hctx, r);
+ hctx->ccid2hctx_rttvar = r >> 1;
+ } else {
+ /* RTTVAR */
+ long tmp = hctx->ccid2hctx_srtt - r;
+ long srtt;
+
+ if (tmp < 0)
+ tmp *= -1;
+
+ tmp >>= 2;
+ hctx->ccid2hctx_rttvar *= 3;
+ hctx->ccid2hctx_rttvar >>= 2;
+ hctx->ccid2hctx_rttvar += tmp;
+
+ /* SRTT */
+ srtt = hctx->ccid2hctx_srtt;
+ srtt *= 7;
+ srtt >>= 3;
+ tmp = r >> 3;
+ srtt += tmp;
+ ccid2_change_srtt(hctx, srtt);
+ }
+ s = hctx->ccid2hctx_rttvar << 2;
+ /* clock granularity is 1 when based on jiffies */
+ if (!s)
+ s = 1;
+ hctx->ccid2hctx_rto = hctx->ccid2hctx_srtt + s;
+
+ /* must be at least a second */
+ s = hctx->ccid2hctx_rto / HZ;
+ /* DCCP doesn't require this [but I like it cuz my code sux] */
+#if 1
+ if (s < 1)
+ hctx->ccid2hctx_rto = HZ;
+#endif
+ /* max 60 seconds */
+ if (s > 60)
+ hctx->ccid2hctx_rto = HZ * 60;
- hctx->cwnd = hctx->cwnd / 2 ? : 1U;
- hctx->ssthresh = max(hctx->cwnd, 2U);
+ hctx->ccid2hctx_lastrtt = jiffies;
- /* Avoid spurious timeouts resulting from Ack Ratio > cwnd */
- if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->cwnd)
- ccid2_change_l_ack_ratio(sk, hctx->cwnd);
+ ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n",
+ hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar,
+ hctx->ccid2hctx_rto, HZ, r);
+ }
+
+ /* we got a new ack, so re-start RTO timer */
+ ccid2_hc_tx_kill_rto_timer(sk);
+ ccid2_start_rto_timer(sk);
}
-static int ccid2_hc_tx_parse_options(struct sock *sk, u8 packet_type,
- u8 option, u8 *optval, u8 optlen)
+static void ccid2_hc_tx_dec_pipe(struct sock *sk)
{
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- switch (option) {
- case DCCPO_ACK_VECTOR_0:
- case DCCPO_ACK_VECTOR_1:
- return dccp_ackvec_parsed_add(&hctx->av_chunks, optval, optlen,
- option - DCCPO_ACK_VECTOR_0);
+ if (hctx->ccid2hctx_pipe == 0)
+ DCCP_BUG("pipe == 0");
+ else
+ hctx->ccid2hctx_pipe--;
+
+ if (hctx->ccid2hctx_pipe == 0)
+ ccid2_hc_tx_kill_rto_timer(sk);
+}
+
+static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp)
+{
+ struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
+
+ if (time_before(seqp->ccid2s_sent, hctx->ccid2hctx_last_cong)) {
+ ccid2_pr_debug("Multiple losses in an RTT---treating as one\n");
+ return;
}
- return 0;
+
+ hctx->ccid2hctx_last_cong = jiffies;
+
+ hctx->ccid2hctx_cwnd = hctx->ccid2hctx_cwnd / 2 ? : 1U;
+ hctx->ccid2hctx_ssthresh = max(hctx->ccid2hctx_cwnd, 2U);
+
+ /* Avoid spurious timeouts resulting from Ack Ratio > cwnd */
+ if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->ccid2hctx_cwnd)
+ ccid2_change_l_ack_ratio(sk, hctx->ccid2hctx_cwnd);
}
static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
- const bool sender_was_blocked = ccid2_cwnd_network_limited(hctx);
- struct dccp_ackvec_parsed *avp;
u64 ackno, seqno;
struct ccid2_seq *seqp;
+ unsigned char *vector;
+ unsigned char veclen;
+ int offset = 0;
int done = 0;
unsigned int maxincr = 0;
+ ccid2_hc_tx_check_sanity(hctx);
/* check reverse path congestion */
seqno = DCCP_SKB_CB(skb)->dccpd_seq;
* -sorbo.
*/
/* need to bootstrap */
- if (hctx->rpdupack == -1) {
- hctx->rpdupack = 0;
- hctx->rpseq = seqno;
+ if (hctx->ccid2hctx_rpdupack == -1) {
+ hctx->ccid2hctx_rpdupack = 0;
+ hctx->ccid2hctx_rpseq = seqno;
} else {
/* check if packet is consecutive */
- if (dccp_delta_seqno(hctx->rpseq, seqno) == 1)
- hctx->rpseq = seqno;
+ if (dccp_delta_seqno(hctx->ccid2hctx_rpseq, seqno) == 1)
+ hctx->ccid2hctx_rpseq = seqno;
/* it's a later packet */
- else if (after48(seqno, hctx->rpseq)) {
- hctx->rpdupack++;
+ else if (after48(seqno, hctx->ccid2hctx_rpseq)) {
+ hctx->ccid2hctx_rpdupack++;
/* check if we got enough dupacks */
- if (hctx->rpdupack >= NUMDUPACK) {
- hctx->rpdupack = -1; /* XXX lame */
- hctx->rpseq = 0;
+ if (hctx->ccid2hctx_rpdupack >= NUMDUPACK) {
+ hctx->ccid2hctx_rpdupack = -1; /* XXX lame */
+ hctx->ccid2hctx_rpseq = 0;
ccid2_change_l_ack_ratio(sk, 2 * dp->dccps_l_ack_ratio);
}
}
/* check forward path congestion */
- if (dccp_packet_without_ack(skb))
+ /* still didn't send out new data packets */
+ if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt)
return;
- /* still didn't send out new data packets */
- if (hctx->seqh == hctx->seqt)
- goto done;
+ switch (DCCP_SKB_CB(skb)->dccpd_type) {
+ case DCCP_PKT_ACK:
+ case DCCP_PKT_DATAACK:
+ break;
+ default:
+ return;
+ }
ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
- if (after48(ackno, hctx->high_ack))
- hctx->high_ack = ackno;
+ if (after48(ackno, hctx->ccid2hctx_high_ack))
+ hctx->ccid2hctx_high_ack = ackno;
- seqp = hctx->seqt;
+ seqp = hctx->ccid2hctx_seqt;
while (before48(seqp->ccid2s_seq, ackno)) {
seqp = seqp->ccid2s_next;
- if (seqp == hctx->seqh) {
- seqp = hctx->seqh->ccid2s_prev;
+ if (seqp == hctx->ccid2hctx_seqh) {
+ seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
break;
}
}
* packets per acknowledgement. Rounding up avoids that cwnd is not
* advanced when Ack Ratio is 1 and gives a slight edge otherwise.
*/
- if (hctx->cwnd < hctx->ssthresh)
+ if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh)
maxincr = DIV_ROUND_UP(dp->dccps_l_ack_ratio, 2);
/* go through all ack vectors */
- list_for_each_entry(avp, &hctx->av_chunks, node) {
+ while ((offset = ccid2_ackvector(sk, skb, offset,
+ &vector, &veclen)) != -1) {
/* go through this ack vector */
- for (; avp->len--; avp->vec++) {
- u64 ackno_end_rl = SUB48(ackno,
- dccp_ackvec_runlen(avp->vec));
+ while (veclen--) {
+ const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
+ u64 ackno_end_rl = SUB48(ackno, rl);
- ccid2_pr_debug("ackvec %llu |%u,%u|\n",
+ ccid2_pr_debug("ackvec start:%llu end:%llu\n",
(unsigned long long)ackno,
- dccp_ackvec_state(avp->vec) >> 6,
- dccp_ackvec_runlen(avp->vec));
+ (unsigned long long)ackno_end_rl);
/* if the seqno we are analyzing is larger than the
* current ackno, then move towards the tail of our
* seqnos.
*/
while (after48(seqp->ccid2s_seq, ackno)) {
- if (seqp == hctx->seqt) {
+ if (seqp == hctx->ccid2hctx_seqt) {
done = 1;
break;
}
* run length
*/
while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) {
- const u8 state = dccp_ackvec_state(avp->vec);
+ const u8 state = *vector &
+ DCCP_ACKVEC_STATE_MASK;
/* new packet received or marked */
- if (state != DCCPAV_NOT_RECEIVED &&
+ if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED &&
!seqp->ccid2s_acked) {
- if (state == DCCPAV_ECN_MARKED)
+ if (state ==
+ DCCP_ACKVEC_STATE_ECN_MARKED) {
ccid2_congestion_event(sk,
seqp);
- else
+ } else
ccid2_new_ack(sk, seqp,
&maxincr);
seqp->ccid2s_acked = 1;
ccid2_pr_debug("Got ack for %llu\n",
(unsigned long long)seqp->ccid2s_seq);
- hctx->pipe--;
+ ccid2_hc_tx_dec_pipe(sk);
}
- if (seqp == hctx->seqt) {
+ if (seqp == hctx->ccid2hctx_seqt) {
done = 1;
break;
}
break;
ackno = SUB48(ackno_end_rl, 1);
+ vector++;
}
if (done)
break;
/* The state about what is acked should be correct now
* Check for NUMDUPACK
*/
- seqp = hctx->seqt;
- while (before48(seqp->ccid2s_seq, hctx->high_ack)) {
+ seqp = hctx->ccid2hctx_seqt;
+ while (before48(seqp->ccid2s_seq, hctx->ccid2hctx_high_ack)) {
seqp = seqp->ccid2s_next;
- if (seqp == hctx->seqh) {
- seqp = hctx->seqh->ccid2s_prev;
+ if (seqp == hctx->ccid2hctx_seqh) {
+ seqp = hctx->ccid2hctx_seqh->ccid2s_prev;
break;
}
}
if (done == NUMDUPACK)
break;
}
- if (seqp == hctx->seqt)
+ if (seqp == hctx->ccid2hctx_seqt)
break;
seqp = seqp->ccid2s_prev;
}
* one ack vector.
*/
ccid2_congestion_event(sk, seqp);
- hctx->pipe--;
+ ccid2_hc_tx_dec_pipe(sk);
}
- if (seqp == hctx->seqt)
+ if (seqp == hctx->ccid2hctx_seqt)
break;
seqp = seqp->ccid2s_prev;
}
- hctx->seqt = last_acked;
+ hctx->ccid2hctx_seqt = last_acked;
}
/* trim acked packets in tail */
- while (hctx->seqt != hctx->seqh) {
- if (!hctx->seqt->ccid2s_acked)
+ while (hctx->ccid2hctx_seqt != hctx->ccid2hctx_seqh) {
+ if (!hctx->ccid2hctx_seqt->ccid2s_acked)
break;
- hctx->seqt = hctx->seqt->ccid2s_next;
+ hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqt->ccid2s_next;
}
- /* restart RTO timer if not all outstanding data has been acked */
- if (hctx->pipe == 0)
- sk_stop_timer(sk, &hctx->rtotimer);
- else
- sk_reset_timer(sk, &hctx->rtotimer, jiffies + hctx->rto);
-done:
- /* check if incoming Acks allow pending packets to be sent */
- if (sender_was_blocked && !ccid2_cwnd_network_limited(hctx))
- tasklet_schedule(&dccp_sk(sk)->dccps_xmitlet);
- dccp_ackvec_parsed_cleanup(&hctx->av_chunks);
+ ccid2_hc_tx_check_sanity(hctx);
}
static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk)
u32 max_ratio;
/* RFC 4341, 5: initialise ssthresh to arbitrarily high (max) value */
- hctx->ssthresh = ~0U;
+ hctx->ccid2hctx_ssthresh = ~0U;
- /* Use larger initial windows (RFC 3390, rfc2581bis) */
- hctx->cwnd = rfc3390_bytes_to_packets(dp->dccps_mss_cache);
+ /*
+ * RFC 4341, 5: "The cwnd parameter is initialized to at most four
+ * packets for new connections, following the rules from [RFC3390]".
+ * We need to convert the bytes of RFC3390 into the packets of RFC 4341.
+ */
+ hctx->ccid2hctx_cwnd = clamp(4380U / dp->dccps_mss_cache, 2U, 4U);
/* Make sure that Ack Ratio is enabled and within bounds. */
- max_ratio = DIV_ROUND_UP(hctx->cwnd, 2);
+ max_ratio = DIV_ROUND_UP(hctx->ccid2hctx_cwnd, 2);
if (dp->dccps_l_ack_ratio == 0 || dp->dccps_l_ack_ratio > max_ratio)
dp->dccps_l_ack_ratio = max_ratio;
if (ccid2_hc_tx_alloc_seq(hctx))
return -ENOMEM;
- hctx->rto = DCCP_TIMEOUT_INIT;
- hctx->rpdupack = -1;
- hctx->last_cong = jiffies;
- setup_timer(&hctx->rtotimer, ccid2_hc_tx_rto_expire, (unsigned long)sk);
- INIT_LIST_HEAD(&hctx->av_chunks);
+ hctx->ccid2hctx_rto = 3 * HZ;
+ ccid2_change_srtt(hctx, -1);
+ hctx->ccid2hctx_rttvar = -1;
+ hctx->ccid2hctx_rpdupack = -1;
+ hctx->ccid2hctx_last_cong = jiffies;
+ setup_timer(&hctx->ccid2hctx_rtotimer, ccid2_hc_tx_rto_expire,
+ (unsigned long)sk);
+
+ ccid2_hc_tx_check_sanity(hctx);
return 0;
}
struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk);
int i;
- sk_stop_timer(sk, &hctx->rtotimer);
+ ccid2_hc_tx_kill_rto_timer(sk);
- for (i = 0; i < hctx->seqbufc; i++)
- kfree(hctx->seqbuf[i]);
- hctx->seqbufc = 0;
+ for (i = 0; i < hctx->ccid2hctx_seqbufc; i++)
+ kfree(hctx->ccid2hctx_seqbuf[i]);
+ hctx->ccid2hctx_seqbufc = 0;
}
static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
switch (DCCP_SKB_CB(skb)->dccpd_type) {
case DCCP_PKT_DATA:
case DCCP_PKT_DATAACK:
- hcrx->data++;
- if (hcrx->data >= dp->dccps_r_ack_ratio) {
+ hcrx->ccid2hcrx_data++;
+ if (hcrx->ccid2hcrx_data >= dp->dccps_r_ack_ratio) {
dccp_send_ack(sk);
- hcrx->data = 0;
+ hcrx->ccid2hcrx_data = 0;
}
break;
}
}
static struct ccid_operations ccid2 = {
- .ccid_id = DCCPC_CCID2,
- .ccid_name = "TCP-like",
- .ccid_owner = THIS_MODULE,
- .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
- .ccid_hc_tx_init = ccid2_hc_tx_init,
- .ccid_hc_tx_exit = ccid2_hc_tx_exit,
- .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet,
- .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent,
- .ccid_hc_tx_parse_options = ccid2_hc_tx_parse_options,
- .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv,
- .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock),
- .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv,
+ .ccid_id = DCCPC_CCID2,
+ .ccid_name = "TCP-like",
+ .ccid_owner = THIS_MODULE,
+ .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock),
+ .ccid_hc_tx_init = ccid2_hc_tx_init,
+ .ccid_hc_tx_exit = ccid2_hc_tx_exit,
+ .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet,
+ .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent,
+ .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv,
+ .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock),
+ .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv,
};
#ifdef CONFIG_IP_DCCP_CCID2_DEBUG
/** struct ccid2_hc_tx_sock - CCID2 TX half connection
*
- * @{cwnd,ssthresh,pipe}: as per RFC 4341, section 5
- * @packets_acked: Ack counter for deriving cwnd growth (RFC 3465)
- * @srtt: smoothed RTT estimate, scaled by 2^3
- * @mdev: smoothed RTT variation, scaled by 2^2
- * @mdev_max: maximum of @mdev during one flight
- * @rttvar: moving average/maximum of @mdev_max
- * @rto: RTO value deriving from SRTT and RTTVAR (RFC 2988)
- * @rtt_seq: to decay RTTVAR at most once per flight
- * @rpseq: last consecutive seqno
- * @rpdupack: dupacks since rpseq
- * @av_chunks: list of Ack Vectors received on current skb
- */
+ * @ccid2hctx_{cwnd,ssthresh,pipe}: as per RFC 4341, section 5
+ * @ccid2hctx_packets_acked - Ack counter for deriving cwnd growth (RFC 3465)
+ * @ccid2hctx_lastrtt -time RTT was last measured
+ * @ccid2hctx_rpseq - last consecutive seqno
+ * @ccid2hctx_rpdupack - dupacks since rpseq
+*/
struct ccid2_hc_tx_sock {
- u32 cwnd;
- u32 ssthresh;
- u32 pipe;
- u32 packets_acked;
- struct ccid2_seq *seqbuf[CCID2_SEQBUF_MAX];
- int seqbufc;
- struct ccid2_seq *seqh;
- struct ccid2_seq *seqt;
- /* RTT measurement: variables/principles are the same as in TCP */
- u32 srtt,
- mdev,
- mdev_max,
- rttvar,
- rto;
- u64 rtt_seq:48;
- struct timer_list rtotimer;
- u64 rpseq;
- int rpdupack;
- unsigned long last_cong;
- u64 high_ack;
- struct list_head av_chunks;
+ u32 ccid2hctx_cwnd;
+ u32 ccid2hctx_ssthresh;
+ u32 ccid2hctx_pipe;
+ u32 ccid2hctx_packets_acked;
+ struct ccid2_seq *ccid2hctx_seqbuf[CCID2_SEQBUF_MAX];
+ int ccid2hctx_seqbufc;
+ struct ccid2_seq *ccid2hctx_seqh;
+ struct ccid2_seq *ccid2hctx_seqt;
+ long ccid2hctx_rto;
+ long ccid2hctx_srtt;
+ long ccid2hctx_rttvar;
+ unsigned long ccid2hctx_lastrtt;
+ struct timer_list ccid2hctx_rtotimer;
+ u64 ccid2hctx_rpseq;
+ int ccid2hctx_rpdupack;
+ unsigned long ccid2hctx_last_cong;
+ u64 ccid2hctx_high_ack;
};
-static inline bool ccid2_cwnd_network_limited(struct ccid2_hc_tx_sock *hctx)
-{
- return (hctx->pipe >= hctx->cwnd);
-}
-
struct ccid2_hc_rx_sock {
- int data;
+ int ccid2hcrx_data;
};
static inline struct ccid2_hc_tx_sock *ccid2_hc_tx_sk(const struct sock *sk)
/*
* Transmitter Half-Connection Routines
*/
-/* Oscillation Prevention/Reduction: recommended by rfc3448bis, on by default */
-static int do_osc_prev = true;
+#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
+static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
+{
+ static char *ccid3_state_names[] = {
+ [TFRC_SSTATE_NO_SENT] = "NO_SENT",
+ [TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
+ [TFRC_SSTATE_FBACK] = "FBACK",
+ [TFRC_SSTATE_TERM] = "TERM",
+ };
+
+ return ccid3_state_names[state];
+}
+#endif
+
+static void ccid3_hc_tx_set_state(struct sock *sk,
+ enum ccid3_hc_tx_states state)
+{
+ struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
+ enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state;
+
+ ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
+ dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
+ ccid3_tx_state_name(state));
+ WARN_ON(state == oldstate);
+ hctx->ccid3hctx_state = state;
+}
/*
* Compute the initial sending rate X_init in the manner of RFC 3390:
*
- * X_init = min(4 * MPS, max(2 * MPS, 4380 bytes)) / RTT
+ * X_init = min(4 * s, max(2 * s, 4380 bytes)) / RTT
*
+ * Note that RFC 3390 uses MSS, RFC 4342 refers to RFC 3390, and rfc3448bis
+ * (rev-02) clarifies the use of RFC 3390 with regard to the above formula.
* For consistency with other parts of the code, X_init is scaled by 2^6.
*/
static inline u64 rfc3390_initial_rate(struct sock *sk)
{
- const u32 mps = dccp_sk(sk)->dccps_mss_cache,
- w_init = clamp(4380U, 2 * mps, 4 * mps);
+ const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
+ const __u32 w_init = clamp_t(__u32, 4380U,
+ 2 * hctx->ccid3hctx_s, 4 * hctx->ccid3hctx_s);
- return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->rtt);
+ return scaled_div(w_init << 6, hctx->ccid3hctx_rtt);
}
-/**
- * ccid3_update_send_interval - Calculate new t_ipi = s / X
- * This respects the granularity of X (64 * bytes/second) and enforces the
- * scaled minimum of s * 64 / t_mbi = `s' bytes/second as per RFC 3448/4342.
+/*
+ * Recalculate t_ipi and delta (should be called whenever X changes)
*/
static void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
{
- if (unlikely(hctx->x <= hctx->s))
- hctx->x = hctx->s;
- hctx->t_ipi = scaled_div32(((u64)hctx->s) << 6, hctx->x);
+ /* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */
+ hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6,
+ hctx->ccid3hctx_x);
+
+ /* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */
+ hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2,
+ TFRC_OPSYS_HALF_TIME_GRAN);
+
+ ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n",
+ hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta,
+ hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6));
+
}
static u32 ccid3_hc_tx_idle_rtt(struct ccid3_hc_tx_sock *hctx, ktime_t now)
{
- u32 delta = ktime_us_delta(now, hctx->t_last_win_count);
+ u32 delta = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count);
- return delta / hctx->rtt;
+ return delta / hctx->ccid3hctx_rtt;
}
/**
static void ccid3_hc_tx_update_x(struct sock *sk, ktime_t *stamp)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- u64 min_rate = 2 * hctx->x_recv;
- const u64 old_x = hctx->x;
+ __u64 min_rate = 2 * hctx->ccid3hctx_x_recv;
+ const __u64 old_x = hctx->ccid3hctx_x;
ktime_t now = stamp ? *stamp : ktime_get_real();
/*
*/
if (ccid3_hc_tx_idle_rtt(hctx, now) >= 2) {
min_rate = rfc3390_initial_rate(sk);
- min_rate = max(min_rate, 2 * hctx->x_recv);
+ min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv);
}
- if (hctx->p > 0) {
+ if (hctx->ccid3hctx_p > 0) {
- hctx->x = min(((u64)hctx->x_calc) << 6, min_rate);
+ hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6,
+ min_rate);
+ hctx->ccid3hctx_x = max(hctx->ccid3hctx_x,
+ (((__u64)hctx->ccid3hctx_s) << 6) /
+ TFRC_T_MBI);
- } else if (ktime_us_delta(now, hctx->t_ld) - (s64)hctx->rtt >= 0) {
+ } else if (ktime_us_delta(now, hctx->ccid3hctx_t_ld)
+ - (s64)hctx->ccid3hctx_rtt >= 0) {
- hctx->x = min(2 * hctx->x, min_rate);
- hctx->x = max(hctx->x,
- scaled_div(((u64)hctx->s) << 6, hctx->rtt));
- hctx->t_ld = now;
+ hctx->ccid3hctx_x = min(2 * hctx->ccid3hctx_x, min_rate);
+ hctx->ccid3hctx_x = max(hctx->ccid3hctx_x,
+ scaled_div(((__u64)hctx->ccid3hctx_s) << 6,
+ hctx->ccid3hctx_rtt));
+ hctx->ccid3hctx_t_ld = now;
}
- if (hctx->x != old_x) {
+ if (hctx->ccid3hctx_x != old_x) {
ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, "
"X_recv=%u\n", (unsigned)(old_x >> 6),
- (unsigned)(hctx->x >> 6), hctx->x_calc,
- (unsigned)(hctx->x_recv >> 6));
+ (unsigned)(hctx->ccid3hctx_x >> 6),
+ hctx->ccid3hctx_x_calc,
+ (unsigned)(hctx->ccid3hctx_x_recv >> 6));
ccid3_update_send_interval(hctx);
}
}
/*
- * ccid3_hc_tx_measure_packet_size - Measuring the packet size `s' (sec 4.1)
- * @new_len: DCCP payload size in bytes (not used by all methods)
+ * Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1)
+ * @len: DCCP packet payload size in bytes
*/
-static u32 ccid3_hc_tx_measure_packet_size(struct sock *sk, const u16 new_len)
+static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len)
{
-#if defined(CONFIG_IP_DCCP_CCID3_MEASURE_S_AS_AVG)
- return tfrc_ewma(ccid3_hc_tx_sk(sk)->s, new_len, 9);
-#elif defined(CONFIG_IP_DCCP_CCID3_MEASURE_S_AS_MAX)
- return max(ccid3_hc_tx_sk(sk)->s, new_len);
-#else /* CONFIG_IP_DCCP_CCID3_MEASURE_S_AS_MPS */
- return dccp_sk(sk)->dccps_mss_cache;
-#endif
+ const u16 old_s = hctx->ccid3hctx_s;
+
+ hctx->ccid3hctx_s = tfrc_ewma(hctx->ccid3hctx_s, len, 9);
+
+ if (hctx->ccid3hctx_s != old_s)
+ ccid3_update_send_interval(hctx);
}
/*
static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx,
ktime_t now)
{
- u32 delta = ktime_us_delta(now, hctx->t_last_win_count),
- quarter_rtts = (4 * delta) / hctx->rtt;
+ u32 delta = ktime_us_delta(now, hctx->ccid3hctx_t_last_win_count),
+ quarter_rtts = (4 * delta) / hctx->ccid3hctx_rtt;
if (quarter_rtts > 0) {
- hctx->t_last_win_count = now;
- hctx->last_win_count += min(quarter_rtts, 5U);
- hctx->last_win_count &= 0xF; /* mod 16 */
+ hctx->ccid3hctx_t_last_win_count = now;
+ hctx->ccid3hctx_last_win_count += min(quarter_rtts, 5U);
+ hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */
}
}
goto restart_timer;
}
- ccid3_pr_debug("%s(%p) entry with%s feedback\n", dccp_role(sk), sk,
- hctx->feedback ? "" : "out");
+ ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk,
+ ccid3_tx_state_name(hctx->ccid3hctx_state));
- /* Ignore and do not restart after leaving the established state */
- if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN))
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_FBACK)
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
+ else if (hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
goto out;
- /* Reset feedback state to "no feedback received" */
- hctx->feedback = false;
-
/*
* Determine new allowed sending rate X as per draft rfc3448bis-00, 4.4
- * RTO is 0 if and only if no feedback has been received yet.
*/
- if (hctx->t_rto == 0 || hctx->p == 0) {
+ if (hctx->ccid3hctx_t_rto == 0 || /* no feedback received yet */
+ hctx->ccid3hctx_p == 0) {
/* halve send rate directly */
- hctx->x /= 2;
+ hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2,
+ (((__u64)hctx->ccid3hctx_s) << 6) /
+ TFRC_T_MBI);
ccid3_update_send_interval(hctx);
-
} else {
/*
* Modify the cached value of X_recv
*
* Note that X_recv is scaled by 2^6 while X_calc is not
*/
- BUG_ON(hctx->p && !hctx->x_calc);
+ BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc);
- if (hctx->x_calc > (hctx->x_recv >> 5))
- hctx->x_recv /= 2;
+ if (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))
+ hctx->ccid3hctx_x_recv =
+ max(hctx->ccid3hctx_x_recv / 2,
+ (((__u64)hctx->ccid3hctx_s) << 6) /
+ (2 * TFRC_T_MBI));
else {
- hctx->x_recv = hctx->x_calc;
- hctx->x_recv <<= 4;
+ hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc;
+ hctx->ccid3hctx_x_recv <<= 4;
}
ccid3_hc_tx_update_x(sk, NULL);
}
ccid3_pr_debug("Reduced X to %llu/64 bytes/sec\n",
- (unsigned long long)hctx->x);
+ (unsigned long long)hctx->ccid3hctx_x);
/*
* Set new timeout for the nofeedback timer.
* See comments in packet_recv() regarding the value of t_RTO.
*/
- if (unlikely(hctx->t_rto == 0)) /* no feedback received yet */
+ if (unlikely(hctx->ccid3hctx_t_rto == 0)) /* no feedback yet */
t_nfb = TFRC_INITIAL_TIMEOUT;
else
- t_nfb = max(hctx->t_rto, 2 * hctx->t_ipi);
+ t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
restart_timer:
- sk_reset_timer(sk, &hctx->no_feedback_timer,
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + usecs_to_jiffies(t_nfb));
out:
bh_unlock_sock(sk);
sock_put(sk);
}
-/**
- * ccid3_hc_tx_send_packet - Delay-based dequeueing of TX packets
- * @skb: next packet candidate to send on @sk
- * This function uses the convention of ccid_packet_dequeue_eval() and
- * returns a millisecond-delay value between 0 and t_mbi = 64000 msec.
+/*
+ * returns
+ * > 0: delay (in msecs) that should pass before actually sending
+ * = 0: can send immediately
+ * < 0: error condition; do not send packet
*/
static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
{
if (unlikely(skb->len == 0))
return -EBADMSG;
- if (hctx->s == 0) {
- sk_reset_timer(sk, &hctx->no_feedback_timer, (jiffies +
+ switch (hctx->ccid3hctx_state) {
+ case TFRC_SSTATE_NO_SENT:
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
+ (jiffies +
usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)));
- hctx->last_win_count = 0;
- hctx->t_last_win_count = now;
+ hctx->ccid3hctx_last_win_count = 0;
+ hctx->ccid3hctx_t_last_win_count = now;
/* Set t_0 for initial packet */
- hctx->t_nom = now;
+ hctx->ccid3hctx_t_nom = now;
+
+ hctx->ccid3hctx_s = skb->len;
/*
* Use initial RTT sample when available: recommended by erratum
*/
if (dp->dccps_syn_rtt) {
ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt);
- hctx->rtt = dp->dccps_syn_rtt;
- hctx->x = rfc3390_initial_rate(sk);
- hctx->t_ld = now;
+ hctx->ccid3hctx_rtt = dp->dccps_syn_rtt;
+ hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
+ hctx->ccid3hctx_t_ld = now;
} else {
/*
* Sender does not have RTT sample:
* is needed in several parts (e.g. window counter);
* - set sending rate X_pps = 1pps as per RFC 3448, 4.2.
*/
- hctx->rtt = DCCP_FALLBACK_RTT;
- hctx->x = dp->dccps_mss_cache;
- hctx->x <<= 6;
+ hctx->ccid3hctx_rtt = DCCP_FALLBACK_RTT;
+ hctx->ccid3hctx_x = hctx->ccid3hctx_s;
+ hctx->ccid3hctx_x <<= 6;
}
-
- /* Compute t_ipi = s / X */
- hctx->s = ccid3_hc_tx_measure_packet_size(sk, skb->len);
ccid3_update_send_interval(hctx);
- /* Seed value for Oscillation Prevention (sec. 4.5) */
- hctx->r_sqmean = tfrc_scaled_sqrt(hctx->rtt);
-
- } else {
- delay = ktime_us_delta(hctx->t_nom, now);
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
+ break;
+ case TFRC_SSTATE_NO_FBACK:
+ case TFRC_SSTATE_FBACK:
+ delay = ktime_us_delta(hctx->ccid3hctx_t_nom, now);
ccid3_pr_debug("delay=%ld\n", (long)delay);
/*
* Scheduling of packet transmissions [RFC 3448, 4.6]
* else
* // send the packet in (t_nom - t_now) milliseconds.
*/
- if (delay >= TFRC_T_DELTA)
- return (u32)delay / USEC_PER_MSEC;
+ if (delay - (s64)hctx->ccid3hctx_delta >= 1000)
+ return (u32)delay / 1000L;
ccid3_hc_tx_update_win_count(hctx, now);
+ break;
+ case TFRC_SSTATE_TERM:
+ DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
+ return -EINVAL;
}
/* prepare to send now (add options etc.) */
dp->dccps_hc_tx_insert_options = 1;
- DCCP_SKB_CB(skb)->dccpd_ccval = hctx->last_win_count;
+ DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
/* set the nominal send time for the next following packet */
- hctx->t_nom = ktime_add_us(hctx->t_nom, hctx->t_ipi);
- return CCID_PACKET_SEND_AT_ONCE;
+ hctx->ccid3hctx_t_nom = ktime_add_us(hctx->ccid3hctx_t_nom,
+ hctx->ccid3hctx_t_ipi);
+ return 0;
}
-static void ccid3_hc_tx_packet_sent(struct sock *sk, unsigned int len)
+static void ccid3_hc_tx_packet_sent(struct sock *sk, int more,
+ unsigned int len)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- /* Changes to s will become effective the next time X is computed */
- hctx->s = ccid3_hc_tx_measure_packet_size(sk, len);
+ ccid3_hc_tx_update_s(hctx, len);
- if (tfrc_tx_hist_add(&hctx->hist, dccp_sk(sk)->dccps_gss))
+ if (tfrc_tx_hist_add(&hctx->ccid3hctx_hist, dccp_sk(sk)->dccps_gss))
DCCP_CRIT("packet history - out of memory!");
}
static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- struct tfrc_tx_hist_entry *acked;
+ struct ccid3_options_received *opt_recv;
ktime_t now;
unsigned long t_nfb;
- u32 r_sample;
+ u32 pinv, r_sample;
/* we are only interested in ACKs */
if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
return;
- /*
- * Locate the acknowledged packet in the TX history.
- *
- * Returning "entry not found" here can for instance happen when
- * - the host has not sent out anything (e.g. a passive server),
- * - the Ack is outdated (packet with higher Ack number was received),
- * - it is a bogus Ack (for a packet not sent on this connection).
- */
- acked = tfrc_tx_hist_find_entry(hctx->hist, dccp_hdr_ack_seq(skb));
- if (acked == NULL)
+ /* ... and only in the established state */
+ if (hctx->ccid3hctx_state != TFRC_SSTATE_FBACK &&
+ hctx->ccid3hctx_state != TFRC_SSTATE_NO_FBACK)
+ return;
+
+ opt_recv = &hctx->ccid3hctx_options_received;
+ now = ktime_get_real();
+
+ /* Estimate RTT from history if ACK number is valid */
+ r_sample = tfrc_tx_hist_rtt(hctx->ccid3hctx_hist,
+ DCCP_SKB_CB(skb)->dccpd_ack_seq, now);
+ if (r_sample == 0) {
+ DCCP_WARN("%s(%p): %s with bogus ACK-%llu\n", dccp_role(sk), sk,
+ dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type),
+ (unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq);
return;
- /* For the sake of RTT sampling, ignore/remove all older entries */
- tfrc_tx_hist_purge(&acked->next);
+ }
- /* Update the moving average for the RTT estimate (RFC 3448, 4.3) */
- now = ktime_get_real();
- r_sample = dccp_sample_rtt(sk, ktime_us_delta(now, acked->stamp));
- hctx->rtt = tfrc_ewma(hctx->rtt, r_sample, 9);
+ /* Update receive rate in units of 64 * bytes/second */
+ hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
+ hctx->ccid3hctx_x_recv <<= 6;
+ /* Update loss event rate (which is scaled by 1e6) */
+ pinv = opt_recv->ccid3or_loss_event_rate;
+ if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */
+ hctx->ccid3hctx_p = 0;
+ else /* can not exceed 100% */
+ hctx->ccid3hctx_p = scaled_div(1, pinv);
+ /*
+ * Validate new RTT sample and update moving average
+ */
+ r_sample = dccp_sample_rtt(sk, r_sample);
+ hctx->ccid3hctx_rtt = tfrc_ewma(hctx->ccid3hctx_rtt, r_sample, 9);
/*
* Update allowed sending rate X as per draft rfc3448bis-00, 4.2/3
*/
- if (!hctx->feedback) {
- hctx->feedback = true;
+ if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
- if (hctx->t_rto == 0) {
+ if (hctx->ccid3hctx_t_rto == 0) {
/*
* Initial feedback packet: Larger Initial Windows (4.2)
*/
- hctx->x = rfc3390_initial_rate(sk);
- hctx->t_ld = now;
+ hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
+ hctx->ccid3hctx_t_ld = now;
ccid3_update_send_interval(hctx);
goto done_computing_x;
- } else if (hctx->p == 0) {
+ } else if (hctx->ccid3hctx_p == 0) {
/*
* First feedback after nofeedback timer expiry (4.3)
*/
}
/* Update sending rate (step 4 of [RFC 3448, 4.3]) */
- if (hctx->p > 0)
- hctx->x_calc = tfrc_calc_x(hctx->s, hctx->rtt, hctx->p);
+ if (hctx->ccid3hctx_p > 0)
+ hctx->ccid3hctx_x_calc =
+ tfrc_calc_x(hctx->ccid3hctx_s,
+ hctx->ccid3hctx_rtt,
+ hctx->ccid3hctx_p);
ccid3_hc_tx_update_x(sk, &now);
done_computing_x:
ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
"p=%u, X_calc=%u, X_recv=%u, X=%u\n",
- dccp_role(sk), sk, hctx->rtt, r_sample,
- hctx->s, hctx->p, hctx->x_calc,
- (unsigned)(hctx->x_recv >> 6),
- (unsigned)(hctx->x >> 6));
- /*
- * Oscillation Reduction (RFC 3448, 4.5) - modifying t_ipi according to
- * RTT changes, multiplying by X/X_inst = sqrt(R_sample)/R_sqmean. This
- * can be useful if few connections share a link, avoiding that buffer
- * fill levels (RTT) oscillate as a result of frequent adjustments to X.
- * A useful presentation with background information is in
- * Joerg Widmer, "Equation-Based Congestion Control",
- * MSc Thesis, University of Mannheim, Germany, 2000
- * (sec. 3.6.4), who calls this ISM ("Inter-packet Space Modulation").
- */
- if (do_osc_prev) {
- r_sample = tfrc_scaled_sqrt(r_sample);
- /*
- * The modulation can work in both ways: increase/decrease t_ipi
- * according to long-term increases/decreases of the RTT. The
- * former is a useful measure, since it works against queue
- * build-up. The latter temporarily increases the sending rate,
- * so that buffers fill up more quickly. This in turn causes
- * the RTT to increase, so that either later reduction becomes
- * necessary or the RTT stays at a very high level. Decreasing
- * t_ipi is therefore not supported.
- * Furthermore, during the initial slow-start phase the RTT
- * naturally increases, where using the algorithm would cause
- * delays. Hence it is disabled during the initial slow-start.
- */
- if (r_sample > hctx->r_sqmean && hctx->p > 0)
- hctx->t_ipi = div_u64((u64)hctx->t_ipi * (u64)r_sample,
- hctx->r_sqmean);
- hctx->t_ipi = min_t(u32, hctx->t_ipi, TFRC_T_MBI);
- /* update R_sqmean _after_ computing the modulation factor */
- hctx->r_sqmean = tfrc_ewma(hctx->r_sqmean, r_sample, 9);
- }
+ dccp_role(sk),
+ sk, hctx->ccid3hctx_rtt, r_sample,
+ hctx->ccid3hctx_s, hctx->ccid3hctx_p,
+ hctx->ccid3hctx_x_calc,
+ (unsigned)(hctx->ccid3hctx_x_recv >> 6),
+ (unsigned)(hctx->ccid3hctx_x >> 6));
/* unschedule no feedback timer */
- sk_stop_timer(sk, &hctx->no_feedback_timer);
+ sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
/*
* As we have calculated new ipi, delta, t_nom it is possible
* This can help avoid triggering the nofeedback timer too
* often ('spinning') on LANs with small RTTs.
*/
- hctx->t_rto = max_t(u32, 4 * hctx->rtt, (CONFIG_IP_DCCP_CCID3_RTO *
- (USEC_PER_SEC / 1000)));
+ hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
+ (CONFIG_IP_DCCP_CCID3_RTO *
+ (USEC_PER_SEC / 1000)));
/*
* Schedule no feedback timer to expire in
* max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
*/
- t_nfb = max(hctx->t_rto, 2 * hctx->t_ipi);
+ t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
"expire in %lu jiffies (%luus)\n",
- dccp_role(sk), sk, usecs_to_jiffies(t_nfb), t_nfb);
+ dccp_role(sk),
+ sk, usecs_to_jiffies(t_nfb), t_nfb);
- sk_reset_timer(sk, &hctx->no_feedback_timer,
+ sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
jiffies + usecs_to_jiffies(t_nfb));
}
-static int ccid3_hc_tx_parse_options(struct sock *sk, u8 packet_type,
- u8 option, u8 *optval, u8 optlen)
+static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
+ unsigned char len, u16 idx,
+ unsigned char *value)
{
+ int rc = 0;
+ const struct dccp_sock *dp = dccp_sk(sk);
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
+ struct ccid3_options_received *opt_recv;
__be32 opt_val;
- switch (option) {
- case TFRC_OPT_RECEIVE_RATE:
- case TFRC_OPT_LOSS_EVENT_RATE:
- /* Must be ignored on Data packets, cf. RFC 4342 8.3 and 8.5 */
- if (packet_type == DCCP_PKT_DATA)
- break;
- if (unlikely(optlen != 4)) {
- DCCP_WARN("%s(%p), invalid len %d for %u\n",
- dccp_role(sk), sk, optlen, option);
- return -EINVAL;
- }
- opt_val = ntohl(get_unaligned((__be32 *)optval));
+ opt_recv = &hctx->ccid3hctx_options_received;
- if (option == TFRC_OPT_RECEIVE_RATE) {
- /* Receive Rate is kept in units of 64 bytes/second */
- hctx->x_recv = opt_val;
- hctx->x_recv <<= 6;
+ if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
+ opt_recv->ccid3or_seqno = dp->dccps_gsr;
+ opt_recv->ccid3or_loss_event_rate = ~0;
+ opt_recv->ccid3or_loss_intervals_idx = 0;
+ opt_recv->ccid3or_loss_intervals_len = 0;
+ opt_recv->ccid3or_receive_rate = 0;
+ }
- ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
- dccp_role(sk), sk, opt_val);
+ switch (option) {
+ case TFRC_OPT_LOSS_EVENT_RATE:
+ if (unlikely(len != 4)) {
+ DCCP_WARN("%s(%p), invalid len %d "
+ "for TFRC_OPT_LOSS_EVENT_RATE\n",
+ dccp_role(sk), sk, len);
+ rc = -EINVAL;
} else {
- /* Update the fixpoint Loss Event Rate fraction */
- hctx->p = tfrc_invert_loss_event_rate(opt_val);
-
+ opt_val = get_unaligned((__be32 *)value);
+ opt_recv->ccid3or_loss_event_rate = ntohl(opt_val);
ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
- dccp_role(sk), sk, opt_val);
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_loss_event_rate);
}
+ break;
+ case TFRC_OPT_LOSS_INTERVALS:
+ opt_recv->ccid3or_loss_intervals_idx = idx;
+ opt_recv->ccid3or_loss_intervals_len = len;
+ ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n",
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_loss_intervals_idx,
+ opt_recv->ccid3or_loss_intervals_len);
+ break;
+ case TFRC_OPT_RECEIVE_RATE:
+ if (unlikely(len != 4)) {
+ DCCP_WARN("%s(%p), invalid len %d "
+ "for TFRC_OPT_RECEIVE_RATE\n",
+ dccp_role(sk), sk, len);
+ rc = -EINVAL;
+ } else {
+ opt_val = get_unaligned((__be32 *)value);
+ opt_recv->ccid3or_receive_rate = ntohl(opt_val);
+ ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
+ dccp_role(sk), sk,
+ opt_recv->ccid3or_receive_rate);
+ }
+ break;
}
- return 0;
+
+ return rc;
}
static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)
{
struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid);
- hctx->hist = NULL;
- setup_timer(&hctx->no_feedback_timer,
- ccid3_hc_tx_no_feedback_timer, (unsigned long)sk);
+ hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
+ hctx->ccid3hctx_hist = NULL;
+ setup_timer(&hctx->ccid3hctx_no_feedback_timer,
+ ccid3_hc_tx_no_feedback_timer, (unsigned long)sk);
+
return 0;
}
{
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- sk_stop_timer(sk, &hctx->no_feedback_timer);
- tfrc_tx_hist_purge(&hctx->hist);
+ ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
+ sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
+
+ tfrc_tx_hist_purge(&hctx->ccid3hctx_hist);
}
static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
{
- info->tcpi_rto = ccid3_hc_tx_sk(sk)->t_rto;
- info->tcpi_rtt = ccid3_hc_tx_sk(sk)->rtt;
+ struct ccid3_hc_tx_sock *hctx;
+
+ /* Listen socks doesn't have a private CCID block */
+ if (sk->sk_state == DCCP_LISTEN)
+ return;
+
+ hctx = ccid3_hc_tx_sk(sk);
+ info->tcpi_rto = hctx->ccid3hctx_t_rto;
+ info->tcpi_rtt = hctx->ccid3hctx_rtt;
}
static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len,
u32 __user *optval, int __user *optlen)
{
- const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
- struct tfrc_tx_info tfrc;
+ const struct ccid3_hc_tx_sock *hctx;
const void *val;
+ /* Listen socks doesn't have a private CCID block */
+ if (sk->sk_state == DCCP_LISTEN)
+ return -EINVAL;
+
+ hctx = ccid3_hc_tx_sk(sk);
switch (optname) {
case DCCP_SOCKOPT_CCID_TX_INFO:
- if (len < sizeof(tfrc))
+ if (len < sizeof(hctx->ccid3hctx_tfrc))
return -EINVAL;
- tfrc.tfrctx_x = hctx->x;
- tfrc.tfrctx_x_recv = hctx->x_recv;
- tfrc.tfrctx_x_calc = hctx->x_calc;
- tfrc.tfrctx_rtt = hctx->rtt;
- tfrc.tfrctx_p = hctx->p;
- tfrc.tfrctx_rto = hctx->t_rto;
- tfrc.tfrctx_ipi = hctx->t_ipi;
- len = sizeof(tfrc);
- val = &tfrc;
+ len = sizeof(hctx->ccid3hctx_tfrc);
+ val = &hctx->ccid3hctx_tfrc;
break;
default:
return -ENOPROTOOPT;
/*
* Receiver Half-Connection Routines
*/
+
+/* CCID3 feedback types */
+enum ccid3_fback_type {
+ CCID3_FBACK_NONE = 0,
+ CCID3_FBACK_INITIAL,
+ CCID3_FBACK_PERIODIC,
+ CCID3_FBACK_PARAM_CHANGE
+};
+
+#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
+static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
+{
+ static char *ccid3_rx_state_names[] = {
+ [TFRC_RSTATE_NO_DATA] = "NO_DATA",
+ [TFRC_RSTATE_DATA] = "DATA",
+ [TFRC_RSTATE_TERM] = "TERM",
+ };
+
+ return ccid3_rx_state_names[state];
+}
+#endif
+
+static void ccid3_hc_rx_set_state(struct sock *sk,
+ enum ccid3_hc_rx_states state)
+{
+ struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
+ enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state;
+
+ ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
+ dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
+ ccid3_rx_state_name(state));
+ WARN_ON(state == oldstate);
+ hcrx->ccid3hcrx_state = state;
+}
+
static void ccid3_hc_rx_send_feedback(struct sock *sk,
const struct sk_buff *skb,
enum ccid3_fback_type fbtype)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
+ struct dccp_sock *dp = dccp_sk(sk);
+ ktime_t now;
+ s64 delta = 0;
+
+ if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_TERM))
+ return;
+
+ now = ktime_get_real();
switch (fbtype) {
case CCID3_FBACK_INITIAL:
- hcrx->x_recv = 0;
- hcrx->p_inverse = ~0U; /* see RFC 4342, 8.5 */
+ hcrx->ccid3hcrx_x_recv = 0;
+ hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */
break;
case CCID3_FBACK_PARAM_CHANGE:
- if (unlikely(hcrx->feedback == CCID3_FBACK_NONE)) {
- /*
- * rfc3448bis-06, 6.3.1: First packet(s) lost or marked
- * FIXME: in rfc3448bis the receiver returns X_recv=0
- * here as it normally would in the first feedback packet.
- * However this is not possible yet, since the code still
- * uses RFC 3448, i.e.
- * If (p > 0)
- * Calculate X_calc using the TCP throughput equation.
- * X = max(min(X_calc, 2*X_recv), s/t_mbi);
- * would bring X down to s/t_mbi. That is why we return
- * X_recv according to rfc3448bis-06 for the moment.
- */
- u32 s = tfrc_rx_hist_packet_size(&hcrx->hist),
- rtt = tfrc_rx_hist_rtt(&hcrx->hist);
-
- hcrx->x_recv = scaled_div32(s, 2 * rtt);
- break;
- }
/*
* When parameters change (new loss or p > p_prev), we do not
* have a reliable estimate for R_m of [RFC 3448, 6.2] and so
- * always check whether at least RTT time units were covered.
+ * need to reuse the previous value of X_recv. However, when
+ * X_recv was 0 (due to early loss), this would kill X down to
+ * s/t_mbi (i.e. one packet in 64 seconds).
+ * To avoid such drastic reduction, we approximate X_recv as
+ * the number of bytes since last feedback.
+ * This is a safe fallback, since X is bounded above by X_calc.
*/
- hcrx->x_recv = tfrc_rx_hist_x_recv(&hcrx->hist, hcrx->x_recv);
- break;
+ if (hcrx->ccid3hcrx_x_recv > 0)
+ break;
+ /* fall through */
case CCID3_FBACK_PERIODIC:
- /*
- * Step (2) of rfc3448bis-06, 6.2:
- * - if no data packets have been received, just restart timer
- * - if data packets have been received, re-compute X_recv
- */
- if (hcrx->hist.bytes_recvd == 0)
- goto prepare_for_next_time;
- hcrx->x_recv = tfrc_rx_hist_x_recv(&hcrx->hist, hcrx->x_recv);
+ delta = ktime_us_delta(now, hcrx->ccid3hcrx_tstamp_last_feedback);
+ if (delta <= 0)
+ DCCP_BUG("delta (%ld) <= 0", (long)delta);
+ else
+ hcrx->ccid3hcrx_x_recv =
+ scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
break;
default:
return;
}
- ccid3_pr_debug("X_recv=%u, 1/p=%u\n", hcrx->x_recv, hcrx->p_inverse);
+ ccid3_pr_debug("Interval %ldusec, X_recv=%u, 1/p=%u\n", (long)delta,
+ hcrx->ccid3hcrx_x_recv, hcrx->ccid3hcrx_pinv);
- dccp_sk(sk)->dccps_hc_rx_insert_options = 1;
- dccp_send_ack(sk);
+ hcrx->ccid3hcrx_tstamp_last_feedback = now;
+ hcrx->ccid3hcrx_last_counter = dccp_hdr(skb)->dccph_ccval;
+ hcrx->ccid3hcrx_bytes_recv = 0;
-prepare_for_next_time:
- tfrc_rx_hist_restart_byte_counter(&hcrx->hist);
- hcrx->last_counter = dccp_hdr(skb)->dccph_ccval;
- hcrx->feedback = fbtype;
+ dp->dccps_hc_rx_insert_options = 1;
+ dccp_send_ack(sk);
}
static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
{
- const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
+ const struct ccid3_hc_rx_sock *hcrx;
__be32 x_recv, pinv;
if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN))
return 0;
+ hcrx = ccid3_hc_rx_sk(sk);
+
if (dccp_packet_without_ack(skb))
return 0;
- x_recv = htonl(hcrx->x_recv);
- pinv = htonl(hcrx->p_inverse);
+ x_recv = htonl(hcrx->ccid3hcrx_x_recv);
+ pinv = htonl(hcrx->ccid3hcrx_pinv);
if (dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
&pinv, sizeof(pinv)) ||
static u32 ccid3_first_li(struct sock *sk)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
- u32 s = tfrc_rx_hist_packet_size(&hcrx->hist),
- rtt = tfrc_rx_hist_rtt(&hcrx->hist), x_recv, p;
+ u32 x_recv, p, delta;
u64 fval;
- /*
- * rfc3448bis-06, 6.3.1: First data packet(s) are marked or lost. Set p
- * to give the equivalent of X_target = s/(2*R). Thus fval = 2 and so p
- * is about 20.64%. This yields an interval length of 4.84 (rounded up).
- */
- if (unlikely(hcrx->feedback == CCID3_FBACK_NONE))
- return 5;
+ if (hcrx->ccid3hcrx_rtt == 0) {
+ DCCP_WARN("No RTT estimate available, using fallback RTT\n");
+ hcrx->ccid3hcrx_rtt = DCCP_FALLBACK_RTT;
+ }
- x_recv = tfrc_rx_hist_x_recv(&hcrx->hist, hcrx->x_recv);
- if (x_recv == 0)
- goto failed;
+ delta = ktime_to_us(net_timedelta(hcrx->ccid3hcrx_tstamp_last_feedback));
+ x_recv = scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
+ if (x_recv == 0) { /* would also trigger divide-by-zero */
+ DCCP_WARN("X_recv==0\n");
+ if ((x_recv = hcrx->ccid3hcrx_x_recv) == 0) {
+ DCCP_BUG("stored value of X_recv is zero");
+ return ~0U;
+ }
+ }
- fval = scaled_div32(scaled_div(s, rtt), x_recv);
+ fval = scaled_div(hcrx->ccid3hcrx_s, hcrx->ccid3hcrx_rtt);
+ fval = scaled_div32(fval, x_recv);
p = tfrc_calc_x_reverse_lookup(fval);
ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
"loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
- if (p > 0)
- return scaled_div(1, p);
-failed:
- return UINT_MAX;
+ return p == 0 ? ~0U : scaled_div(1, p);
}
static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
+ enum ccid3_fback_type do_feedback = CCID3_FBACK_NONE;
const u64 ndp = dccp_sk(sk)->dccps_options_received.dccpor_ndp;
const bool is_data_packet = dccp_data_packet(skb);
+ if (unlikely(hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)) {
+ if (is_data_packet) {
+ const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
+ do_feedback = CCID3_FBACK_INITIAL;
+ ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
+ hcrx->ccid3hcrx_s = payload;
+ /*
+ * Not necessary to update ccid3hcrx_bytes_recv here,
+ * since X_recv = 0 for the first feedback packet (cf.
+ * RFC 3448, 6.3) -- gerrit
+ */
+ }
+ goto update_records;
+ }
+
+ if (tfrc_rx_hist_duplicate(&hcrx->ccid3hcrx_hist, skb))
+ return; /* done receiving */
+
+ if (is_data_packet) {
+ const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
+ /*
+ * Update moving-average of s and the sum of received payload bytes
+ */
+ hcrx->ccid3hcrx_s = tfrc_ewma(hcrx->ccid3hcrx_s, payload, 9);
+ hcrx->ccid3hcrx_bytes_recv += payload;
+ }
+
/*
* Perform loss detection and handle pending losses
*/
- if (tfrc_rx_congestion_event(&hcrx->hist, &hcrx->li_hist,
- skb, ndp, ccid3_first_li, sk))
- ccid3_hc_rx_send_feedback(sk, skb, CCID3_FBACK_PARAM_CHANGE);
+ if (tfrc_rx_handle_loss(&hcrx->ccid3hcrx_hist, &hcrx->ccid3hcrx_li_hist,
+ skb, ndp, ccid3_first_li, sk)) {
+ do_feedback = CCID3_FBACK_PARAM_CHANGE;
+ goto done_receiving;
+ }
+
+ if (tfrc_rx_hist_loss_pending(&hcrx->ccid3hcrx_hist))
+ return; /* done receiving */
+
/*
- * Feedback for first non-empty data packet (RFC 3448, 6.3)
+ * Handle data packets: RTT sampling and monitoring p
*/
- else if (unlikely(hcrx->feedback == CCID3_FBACK_NONE && is_data_packet))
- ccid3_hc_rx_send_feedback(sk, skb, CCID3_FBACK_INITIAL);
+ if (unlikely(!is_data_packet))
+ goto update_records;
+
+ if (!tfrc_lh_is_initialised(&hcrx->ccid3hcrx_li_hist)) {
+ const u32 sample = tfrc_rx_hist_sample_rtt(&hcrx->ccid3hcrx_hist, skb);
+ /*
+ * Empty loss history: no loss so far, hence p stays 0.
+ * Sample RTT values, since an RTT estimate is required for the
+ * computation of p when the first loss occurs; RFC 3448, 6.3.1.
+ */
+ if (sample != 0)
+ hcrx->ccid3hcrx_rtt = tfrc_ewma(hcrx->ccid3hcrx_rtt, sample, 9);
+
+ } else if (tfrc_lh_update_i_mean(&hcrx->ccid3hcrx_li_hist, skb)) {
+ /*
+ * Step (3) of [RFC 3448, 6.1]: Recompute I_mean and, if I_mean
+ * has decreased (resp. p has increased), send feedback now.
+ */
+ do_feedback = CCID3_FBACK_PARAM_CHANGE;
+ }
+
/*
* Check if the periodic once-per-RTT feedback is due; RFC 4342, 10.3
*/
- else if (!tfrc_rx_hist_loss_pending(&hcrx->hist) && is_data_packet &&
- SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->last_counter) > 3)
- ccid3_hc_rx_send_feedback(sk, skb, CCID3_FBACK_PERIODIC);
+ if (SUB16(dccp_hdr(skb)->dccph_ccval, hcrx->ccid3hcrx_last_counter) > 3)
+ do_feedback = CCID3_FBACK_PERIODIC;
+
+update_records:
+ tfrc_rx_hist_add_packet(&hcrx->ccid3hcrx_hist, skb, ndp);
+
+done_receiving:
+ if (do_feedback)
+ ccid3_hc_rx_send_feedback(sk, skb, do_feedback);
}
static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk)
{
struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid);
- tfrc_lh_init(&hcrx->li_hist);
- return tfrc_rx_hist_init(&hcrx->hist, sk);
+ hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
+ tfrc_lh_init(&hcrx->ccid3hcrx_li_hist);
+ return tfrc_rx_hist_alloc(&hcrx->ccid3hcrx_hist);
}
static void ccid3_hc_rx_exit(struct sock *sk)
{
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
- tfrc_rx_hist_purge(&hcrx->hist);
- tfrc_lh_cleanup(&hcrx->li_hist);
+ ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
+
+ tfrc_rx_hist_purge(&hcrx->ccid3hcrx_hist);
+ tfrc_lh_cleanup(&hcrx->ccid3hcrx_li_hist);
}
static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
{
+ const struct ccid3_hc_rx_sock *hcrx;
+
+ /* Listen socks doesn't have a private CCID block */
+ if (sk->sk_state == DCCP_LISTEN)
+ return;
+
+ hcrx = ccid3_hc_rx_sk(sk);
+ info->tcpi_ca_state = hcrx->ccid3hcrx_state;
info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
- info->tcpi_rcv_rtt = tfrc_rx_hist_rtt(&ccid3_hc_rx_sk(sk)->hist);
+ info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt;
}
static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
u32 __user *optval, int __user *optlen)
{
- const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
+ const struct ccid3_hc_rx_sock *hcrx;
struct tfrc_rx_info rx_info;
const void *val;
+ /* Listen socks doesn't have a private CCID block */
+ if (sk->sk_state == DCCP_LISTEN)
+ return -EINVAL;
+
+ hcrx = ccid3_hc_rx_sk(sk);
switch (optname) {
case DCCP_SOCKOPT_CCID_RX_INFO:
if (len < sizeof(rx_info))
return -EINVAL;
- rx_info.tfrcrx_x_recv = hcrx->x_recv;
- rx_info.tfrcrx_rtt = tfrc_rx_hist_rtt(&hcrx->hist);
- rx_info.tfrcrx_p = tfrc_invert_loss_event_rate(hcrx->p_inverse);
+ rx_info.tfrcrx_x_recv = hcrx->ccid3hcrx_x_recv;
+ rx_info.tfrcrx_rtt = hcrx->ccid3hcrx_rtt;
+ rx_info.tfrcrx_p = hcrx->ccid3hcrx_pinv == 0 ? ~0U :
+ scaled_div(1, hcrx->ccid3hcrx_pinv);
len = sizeof(rx_info);
val = &rx_info;
break;
.ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt,
};
-module_param(do_osc_prev, bool, 0644);
-MODULE_PARM_DESC(do_osc_prev, "Use Oscillation Prevention (RFC 3448, 4.5)");
-
#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
module_param(ccid3_debug, bool, 0644);
MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
static __init int ccid3_module_init(void)
{
- struct timespec tp;
-
- /*
- * Without a fine-grained clock resolution, RTTs/X_recv are not sampled
- * correctly and feedback is sent either too early or too late.
- */
- hrtimer_get_res(CLOCK_MONOTONIC, &tp);
- if (tp.tv_sec || tp.tv_nsec > DCCP_TIME_RESOLUTION * NSEC_PER_USEC) {
- printk(KERN_ERR "%s: Timer too coarse (%ld usec), need %u-usec"
- " resolution - check your clocksource.\n", __func__,
- tp.tv_nsec/NSEC_PER_USEC, DCCP_TIME_RESOLUTION);
- return -ESOCKTNOSUPPORT;
- }
return ccid_register(&ccid3);
}
module_init(ccid3_module_init);
/* Two seconds as per RFC 3448 4.2 */
#define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC)
-/* Maximum backoff interval t_mbi (RFC 3448, 4.3) */
-#define TFRC_T_MBI (64 * USEC_PER_SEC)
+/* In usecs - half the scheduling granularity as per RFC3448 4.6 */
+#define TFRC_OPSYS_HALF_TIME_GRAN (USEC_PER_SEC / (2 * HZ))
-/*
- * The t_delta parameter (RFC 3448, 4.6): delays of less than %USEC_PER_MSEC are
- * rounded down to 0, since sk_reset_timer() here uses millisecond granularity.
- * Hence we can use a constant t_delta = %USEC_PER_MSEC when HZ >= 500. A coarse
- * resolution of HZ < 500 means that the error is below one timer tick (t_gran)
- * when using the constant t_delta = t_gran / 2 = %USEC_PER_SEC / (2 * HZ).
- */
-#if (HZ >= 500)
-# define TFRC_T_DELTA USEC_PER_MSEC
-#else
-# define TFRC_T_DELTA (USEC_PER_SEC / (2 * HZ))
-#warning Coarse CONFIG_HZ resolution -- higher value recommended for TFRC.
-#endif
+/* Parameter t_mbi from [RFC 3448, 4.3]: backoff interval in seconds */
+#define TFRC_T_MBI 64
enum ccid3_options {
TFRC_OPT_LOSS_EVENT_RATE = 192,
TFRC_OPT_RECEIVE_RATE = 194,
};
+struct ccid3_options_received {
+ u64 ccid3or_seqno:48,
+ ccid3or_loss_intervals_idx:16;
+ u16 ccid3or_loss_intervals_len;
+ u32 ccid3or_loss_event_rate;
+ u32 ccid3or_receive_rate;
+};
+
+/* TFRC sender states */
+enum ccid3_hc_tx_states {
+ TFRC_SSTATE_NO_SENT = 1,
+ TFRC_SSTATE_NO_FBACK,
+ TFRC_SSTATE_FBACK,
+ TFRC_SSTATE_TERM,
+};
+
/** struct ccid3_hc_tx_sock - CCID3 sender half-connection socket
*
- * @x - Current sending rate in 64 * bytes per second
- * @x_recv - Receive rate in 64 * bytes per second
- * @x_calc - Calculated rate in bytes per second
- * @rtt - Estimate of current round trip time in usecs
- * @r_sqmean - Estimate of long-term RTT (RFC 3448, 4.5)
- * @p - Current loss event rate (0-1) scaled by 1000000
- * @s - Packet size in bytes
- * @t_rto - Nofeedback Timer setting in usecs
- * @t_ipi - Interpacket (send) interval (RFC 3448, 4.6) in usecs
- * @feedback - Whether feedback has been received or not
- * @last_win_count - Last window counter sent
- * @t_last_win_count - Timestamp of earliest packet with
- * last_win_count value sent
- * @no_feedback_timer - Handle to no feedback timer
- * @t_ld - Time last doubled during slow start
- * @t_nom - Nominal send time of next packet
- * @hist - Packet history
+ * @ccid3hctx_x - Current sending rate in 64 * bytes per second
+ * @ccid3hctx_x_recv - Receive rate in 64 * bytes per second
+ * @ccid3hctx_x_calc - Calculated rate in bytes per second
+ * @ccid3hctx_rtt - Estimate of current round trip time in usecs
+ * @ccid3hctx_p - Current loss event rate (0-1) scaled by 1000000
+ * @ccid3hctx_s - Packet size in bytes
+ * @ccid3hctx_t_rto - Nofeedback Timer setting in usecs
+ * @ccid3hctx_t_ipi - Interpacket (send) interval (RFC 3448, 4.6) in usecs
+ * @ccid3hctx_state - Sender state, one of %ccid3_hc_tx_states
+ * @ccid3hctx_last_win_count - Last window counter sent
+ * @ccid3hctx_t_last_win_count - Timestamp of earliest packet
+ * with last_win_count value sent
+ * @ccid3hctx_no_feedback_timer - Handle to no feedback timer
+ * @ccid3hctx_t_ld - Time last doubled during slow start
+ * @ccid3hctx_t_nom - Nominal send time of next packet
+ * @ccid3hctx_delta - Send timer delta (RFC 3448, 4.6) in usecs
+ * @ccid3hctx_hist - Packet history
+ * @ccid3hctx_options_received - Parsed set of retrieved options
*/
struct ccid3_hc_tx_sock {
- u64 x;
- u64 x_recv;
- u32 x_calc;
- u32 rtt;
- u16 r_sqmean;
- u32 p;
- u32 t_rto;
- u32 t_ipi;
- u16 s;
- bool feedback:1;
- u8 last_win_count;
- ktime_t t_last_win_count;
- struct timer_list no_feedback_timer;
- ktime_t t_ld;
- ktime_t t_nom;
- struct tfrc_tx_hist_entry *hist;
+ struct tfrc_tx_info ccid3hctx_tfrc;
+#define ccid3hctx_x ccid3hctx_tfrc.tfrctx_x
+#define ccid3hctx_x_recv ccid3hctx_tfrc.tfrctx_x_recv
+#define ccid3hctx_x_calc ccid3hctx_tfrc.tfrctx_x_calc
+#define ccid3hctx_rtt ccid3hctx_tfrc.tfrctx_rtt
+#define ccid3hctx_p ccid3hctx_tfrc.tfrctx_p
+#define ccid3hctx_t_rto ccid3hctx_tfrc.tfrctx_rto
+#define ccid3hctx_t_ipi ccid3hctx_tfrc.tfrctx_ipi
+ u16 ccid3hctx_s;
+ enum ccid3_hc_tx_states ccid3hctx_state:8;
+ u8 ccid3hctx_last_win_count;
+ ktime_t ccid3hctx_t_last_win_count;
+ struct timer_list ccid3hctx_no_feedback_timer;
+ ktime_t ccid3hctx_t_ld;
+ ktime_t ccid3hctx_t_nom;
+ u32 ccid3hctx_delta;
+ struct tfrc_tx_hist_entry *ccid3hctx_hist;
+ struct ccid3_options_received ccid3hctx_options_received;
};
static inline struct ccid3_hc_tx_sock *ccid3_hc_tx_sk(const struct sock *sk)
return hctx;
}
-
-enum ccid3_fback_type {
- CCID3_FBACK_NONE = 0,
- CCID3_FBACK_INITIAL,
- CCID3_FBACK_PERIODIC,
- CCID3_FBACK_PARAM_CHANGE
+/* TFRC receiver states */
+enum ccid3_hc_rx_states {
+ TFRC_RSTATE_NO_DATA = 1,
+ TFRC_RSTATE_DATA,
+ TFRC_RSTATE_TERM = 127,
};
/** struct ccid3_hc_rx_sock - CCID3 receiver half-connection socket
*
- * @last_counter - Tracks window counter (RFC 4342, 8.1)
- * @feedback - The type of the feedback last sent
- * @x_recv - Receiver estimate of send rate (RFC 3448, sec. 4.3)
- * @tstamp_last_feedback - Time at which last feedback was sent
- * @hist - Packet history (loss detection + RTT sampling)
- * @li_hist - Loss Interval database
- * @p_inverse - Inverse of Loss Event Rate (RFC 4342, sec. 8.5)
+ * @ccid3hcrx_x_recv - Receiver estimate of send rate (RFC 3448 4.3)
+ * @ccid3hcrx_rtt - Receiver estimate of rtt (non-standard)
+ * @ccid3hcrx_p - Current loss event rate (RFC 3448 5.4)
+ * @ccid3hcrx_last_counter - Tracks window counter (RFC 4342, 8.1)
+ * @ccid3hcrx_state - Receiver state, one of %ccid3_hc_rx_states
+ * @ccid3hcrx_bytes_recv - Total sum of DCCP payload bytes
+ * @ccid3hcrx_x_recv - Receiver estimate of send rate (RFC 3448, sec. 4.3)
+ * @ccid3hcrx_rtt - Receiver estimate of RTT
+ * @ccid3hcrx_tstamp_last_feedback - Time at which last feedback was sent
+ * @ccid3hcrx_tstamp_last_ack - Time at which last feedback was sent
+ * @ccid3hcrx_hist - Packet history (loss detection + RTT sampling)
+ * @ccid3hcrx_li_hist - Loss Interval database
+ * @ccid3hcrx_s - Received packet size in bytes
+ * @ccid3hcrx_pinv - Inverse of Loss Event Rate (RFC 4342, sec. 8.5)
*/
struct ccid3_hc_rx_sock {
- u8 last_counter:4;
- enum ccid3_fback_type feedback:4;
- u32 x_recv;
- ktime_t tstamp_last_feedback;
- struct tfrc_rx_hist hist;
- struct tfrc_loss_hist li_hist;
-#define p_inverse li_hist.i_mean
+ u8 ccid3hcrx_last_counter:4;
+ enum ccid3_hc_rx_states ccid3hcrx_state:8;
+ u32 ccid3hcrx_bytes_recv;
+ u32 ccid3hcrx_x_recv;
+ u32 ccid3hcrx_rtt;
+ ktime_t ccid3hcrx_tstamp_last_feedback;
+ struct tfrc_rx_hist ccid3hcrx_hist;
+ struct tfrc_loss_hist ccid3hcrx_li_hist;
+ u16 ccid3hcrx_s;
+#define ccid3hcrx_pinv ccid3hcrx_li_hist.i_mean
};
static inline struct ccid3_hc_rx_sock *ccid3_hc_rx_sk(const struct sock *sk)
/**
* tfrc_lh_update_i_mean - Update the `open' loss interval I_0
- * This updates I_mean as the sequence numbers increase. As a consequence, the
- * open loss interval I_0 increases, hence p = W_tot/max(I_tot0, I_tot1)
- * decreases, and thus there is no need to send renewed feedback.
+ * For recomputing p: returns `true' if p > p_prev <=> 1/p < 1/p_prev
*/
-void tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
+u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *skb)
{
struct tfrc_loss_interval *cur = tfrc_lh_peek(lh);
+ u32 old_i_mean = lh->i_mean;
s64 len;
if (cur == NULL) /* not initialised */
- return;
-
- /* FIXME: should probably also count non-data packets (RFC 4342, 6.1) */
- if (!dccp_data_packet(skb))
- return;
+ return 0;
len = dccp_delta_seqno(cur->li_seqno, DCCP_SKB_CB(skb)->dccpd_seq) + 1;
if (len - (s64)cur->li_length <= 0) /* duplicate or reordered */
- return;
+ return 0;
if (SUB16(dccp_hdr(skb)->dccph_ccval, cur->li_ccval) > 4)
/*
cur->li_is_closed = 1;
if (tfrc_lh_length(lh) == 1) /* due to RFC 3448, 6.3.1 */
- return;
+ return 0;
cur->li_length = len;
tfrc_lh_calc_i_mean(lh);
+
+ return (lh->i_mean < old_i_mean);
}
+EXPORT_SYMBOL_GPL(tfrc_lh_update_i_mean);
/* Determine if `new_loss' does begin a new loss interval [RFC 4342, 10.2] */
static inline u8 tfrc_lh_is_new_loss(struct tfrc_loss_interval *cur,
* @sk: Used by @calc_first_li in caller-specific way (subtyping)
* Updates I_mean and returns 1 if a new interval has in fact been added to @lh.
*/
-bool tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
- u32 (*calc_first_li)(struct sock *), struct sock *sk)
+int tfrc_lh_interval_add(struct tfrc_loss_hist *lh, struct tfrc_rx_hist *rh,
+ u32 (*calc_first_li)(struct sock *), struct sock *sk)
{
struct tfrc_loss_interval *cur = tfrc_lh_peek(lh), *new;
if (cur != NULL && !tfrc_lh_is_new_loss(cur, tfrc_rx_hist_loss_prev(rh)))
- return false;
+ return 0;
new = tfrc_lh_demand_next(lh);
if (unlikely(new == NULL)) {
DCCP_CRIT("Cannot allocate/add loss record.");
- return false;
+ return 0;
}
new->li_seqno = tfrc_rx_hist_loss_prev(rh)->tfrchrx_seqno;
tfrc_lh_calc_i_mean(lh);
}
- return true;
+ return 1;
}
EXPORT_SYMBOL_GPL(tfrc_lh_interval_add);
struct tfrc_rx_hist;
-extern bool tfrc_lh_interval_add(struct tfrc_loss_hist *, struct tfrc_rx_hist *,
+extern int tfrc_lh_interval_add(struct tfrc_loss_hist *, struct tfrc_rx_hist *,
u32 (*first_li)(struct sock *), struct sock *);
-extern void tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *);
+extern u8 tfrc_lh_update_i_mean(struct tfrc_loss_hist *lh, struct sk_buff *);
extern void tfrc_lh_cleanup(struct tfrc_loss_hist *lh);
#endif /* _DCCP_LI_HIST_ */
#include "packet_history.h"
#include "../../dccp.h"
+/**
+ * tfrc_tx_hist_entry - Simple singly-linked TX history list
+ * @next: next oldest entry (LIFO order)
+ * @seqno: sequence number of this entry
+ * @stamp: send time of packet with sequence number @seqno
+ */
+struct tfrc_tx_hist_entry {
+ struct tfrc_tx_hist_entry *next;
+ u64 seqno;
+ ktime_t stamp;
+};
+
/*
* Transmitter History Routines
*/
}
}
+static struct tfrc_tx_hist_entry *
+ tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 seqno)
+{
+ while (head != NULL && head->seqno != seqno)
+ head = head->next;
+
+ return head;
+}
+
int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno)
{
struct tfrc_tx_hist_entry *entry = kmem_cache_alloc(tfrc_tx_hist_slab, gfp_any());
}
EXPORT_SYMBOL_GPL(tfrc_tx_hist_purge);
+u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head, const u64 seqno,
+ const ktime_t now)
+{
+ u32 rtt = 0;
+ struct tfrc_tx_hist_entry *packet = tfrc_tx_hist_find_entry(head, seqno);
+
+ if (packet != NULL) {
+ rtt = ktime_us_delta(now, packet->stamp);
+ /*
+ * Garbage-collect older (irrelevant) entries:
+ */
+ tfrc_tx_hist_purge(&packet->next);
+ }
+
+ return rtt;
+}
+EXPORT_SYMBOL_GPL(tfrc_tx_hist_rtt);
+
+
/*
* Receiver History Routines
*/
}
EXPORT_SYMBOL_GPL(tfrc_rx_hist_duplicate);
-
-static void __tfrc_rx_hist_swap(struct tfrc_rx_hist *h, const u8 a, const u8 b)
-{
- struct tfrc_rx_hist_entry *tmp = h->ring[a];
-
- h->ring[a] = h->ring[b];
- h->ring[b] = tmp;
-}
-
static void tfrc_rx_hist_swap(struct tfrc_rx_hist *h, const u8 a, const u8 b)
{
- __tfrc_rx_hist_swap(h, tfrc_rx_hist_index(h, a),
- tfrc_rx_hist_index(h, b));
-}
+ const u8 idx_a = tfrc_rx_hist_index(h, a),
+ idx_b = tfrc_rx_hist_index(h, b);
+ struct tfrc_rx_hist_entry *tmp = h->ring[idx_a];
-/**
- * tfrc_rx_hist_resume_rtt_sampling - Prepare RX history for RTT sampling
- * This is called after loss detection has finished, when the history entry
- * with the index of `loss_count' holds the highest-received sequence number.
- * RTT sampling requires this information at ring[0] (tfrc_rx_hist_sample_rtt).
- */
-static inline void tfrc_rx_hist_resume_rtt_sampling(struct tfrc_rx_hist *h)
-{
- __tfrc_rx_hist_swap(h, 0, tfrc_rx_hist_index(h, h->loss_count));
- h->loss_count = h->loss_start = 0;
+ h->ring[idx_a] = h->ring[idx_b];
+ h->ring[idx_b] = tmp;
}
/*
u64 s0 = tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno,
s1 = DCCP_SKB_CB(skb)->dccpd_seq;
- if (!dccp_loss_free(s0, s1, n1)) /* gap between S0 and S1 */
+ if (!dccp_loss_free(s0, s1, n1)) { /* gap between S0 and S1 */
h->loss_count = 1;
+ tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_entry(h, 1), skb, n1);
+ }
}
static void __one_after_loss(struct tfrc_rx_hist *h, struct sk_buff *skb, u32 n2)
if (dccp_loss_free(s2, s1, n1)) {
/* hole is filled: S0, S2, and S1 are consecutive */
- tfrc_rx_hist_resume_rtt_sampling(h);
+ h->loss_count = 0;
+ h->loss_start = tfrc_rx_hist_index(h, 1);
} else
/* gap between S2 and S1: just update loss_prev */
tfrc_rx_hist_entry_from_skb(tfrc_rx_hist_loss_prev(h), skb, n2);
if (dccp_loss_free(s1, s2, n2)) {
/* entire hole filled by S0, S3, S1, S2 */
- tfrc_rx_hist_resume_rtt_sampling(h);
+ h->loss_start = tfrc_rx_hist_index(h, 2);
+ h->loss_count = 0;
} else {
/* gap remains between S1 and S2 */
h->loss_start = tfrc_rx_hist_index(h, 1);
if (dccp_loss_free(s2, s3, n3)) {
/* no gap between S2 and S3: entire hole is filled */
- tfrc_rx_hist_resume_rtt_sampling(h);
+ h->loss_start = tfrc_rx_hist_index(h, 3);
+ h->loss_count = 0;
} else {
/* gap between S2 and S3 */
h->loss_start = tfrc_rx_hist_index(h, 2);
}
/**
- * tfrc_rx_congestion_event - Loss detection and further processing
- * @h: The non-empty RX history object
- * @lh: Loss Intervals database to update
- * @skb: Currently received packet
- * @ndp: The NDP count belonging to @skb
- * @first_li: Caller-dependent computation of first loss interval in @lh
- * @sk: Used by @calc_first_li (see tfrc_lh_interval_add)
+ * tfrc_rx_handle_loss - Loss detection and further processing
+ * @h: The non-empty RX history object
+ * @lh: Loss Intervals database to update
+ * @skb: Currently received packet
+ * @ndp: The NDP count belonging to @skb
+ * @calc_first_li: Caller-dependent computation of first loss interval in @lh
+ * @sk: Used by @calc_first_li (see tfrc_lh_interval_add)
* Chooses action according to pending loss, updates LI database when a new
* loss was detected, and does required post-processing. Returns 1 when caller
* should send feedback, 0 otherwise.
* records accordingly, the caller should not perform any more RX history
* operations when loss_count is greater than 0 after calling this function.
*/
-bool tfrc_rx_congestion_event(struct tfrc_rx_hist *h,
- struct tfrc_loss_hist *lh,
- struct sk_buff *skb, const u64 ndp,
- u32 (*first_li)(struct sock *), struct sock *sk)
+int tfrc_rx_handle_loss(struct tfrc_rx_hist *h,
+ struct tfrc_loss_hist *lh,
+ struct sk_buff *skb, const u64 ndp,
+ u32 (*calc_first_li)(struct sock *), struct sock *sk)
{
- bool new_event = false;
-
- if (tfrc_rx_hist_duplicate(h, skb))
- return 0;
+ int is_new_loss = 0;
if (h->loss_count == 0) {
__do_track_loss(h, skb, ndp);
- tfrc_rx_hist_sample_rtt(h, skb);
- tfrc_rx_hist_add_packet(h, skb, ndp);
} else if (h->loss_count == 1) {
__one_after_loss(h, skb, ndp);
} else if (h->loss_count != 2) {
/*
* Update Loss Interval database and recycle RX records
*/
- new_event = tfrc_lh_interval_add(lh, h, first_li, sk);
+ is_new_loss = tfrc_lh_interval_add(lh, h, calc_first_li, sk);
__three_after_loss(h);
}
-
- /*
- * Update moving-average of `s' and the sum of received payload bytes.
- */
- if (dccp_data_packet(skb)) {
- const u32 payload = skb->len - dccp_hdr(skb)->dccph_doff * 4;
-
- h->packet_size = tfrc_ewma(h->packet_size, payload, 9);
- h->bytes_recvd += payload;
- }
-
- /* RFC 3448, 6.1: update I_0, whose growth implies p <= p_prev */
- if (!new_event)
- tfrc_lh_update_i_mean(lh, skb);
-
- return new_event;
+ return is_new_loss;
}
-EXPORT_SYMBOL_GPL(tfrc_rx_congestion_event);
+EXPORT_SYMBOL_GPL(tfrc_rx_handle_loss);
-/* Compute the sending rate X_recv measured between feedback intervals */
-u32 tfrc_rx_hist_x_recv(struct tfrc_rx_hist *h, const u32 last_x_recv)
+int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h)
{
- u64 bytes = h->bytes_recvd, last_rtt = h->rtt_estimate;
- s64 delta = ktime_to_us(net_timedelta(h->bytes_start));
-
- WARN_ON(delta <= 0);
- /*
- * Ensure that the sampling interval for X_recv is at least one RTT,
- * by extending the sampling interval backwards in time, over the last
- * R_(m-1) seconds, as per rfc3448bis-06, 6.2.
- * To reduce noise (e.g. when the RTT changes often), this is only
- * done when delta is smaller than RTT/2.
- */
- if (last_x_recv > 0 && delta < last_rtt/2) {
- tfrc_pr_debug("delta < RTT ==> %ld us < %u us\n",
- (long)delta, (unsigned)last_rtt);
+ int i;
- delta = (bytes ? delta : 0) + last_rtt;
- bytes += div_u64((u64)last_x_recv * last_rtt, USEC_PER_SEC);
+ for (i = 0; i <= TFRC_NDUPACK; i++) {
+ h->ring[i] = kmem_cache_alloc(tfrc_rx_hist_slab, GFP_ATOMIC);
+ if (h->ring[i] == NULL)
+ goto out_free;
}
- if (unlikely(bytes == 0)) {
- DCCP_WARN("X_recv == 0, using old value of %u\n", last_x_recv);
- return last_x_recv;
+ h->loss_count = h->loss_start = 0;
+ return 0;
+
+out_free:
+ while (i-- != 0) {
+ kmem_cache_free(tfrc_rx_hist_slab, h->ring[i]);
+ h->ring[i] = NULL;
}
- return scaled_div32(bytes, delta);
+ return -ENOBUFS;
}
-EXPORT_SYMBOL_GPL(tfrc_rx_hist_x_recv);
+EXPORT_SYMBOL_GPL(tfrc_rx_hist_alloc);
void tfrc_rx_hist_purge(struct tfrc_rx_hist *h)
{
}
EXPORT_SYMBOL_GPL(tfrc_rx_hist_purge);
-static int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h)
+/**
+ * tfrc_rx_hist_rtt_last_s - reference entry to compute RTT samples against
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_rtt_last_s(const struct tfrc_rx_hist *h)
{
- int i;
-
- memset(h, 0, sizeof(*h));
-
- for (i = 0; i <= TFRC_NDUPACK; i++) {
- h->ring[i] = kmem_cache_alloc(tfrc_rx_hist_slab, GFP_ATOMIC);
- if (h->ring[i] == NULL) {
- tfrc_rx_hist_purge(h);
- return -ENOBUFS;
- }
- }
- return 0;
+ return h->ring[0];
}
-int tfrc_rx_hist_init(struct tfrc_rx_hist *h, struct sock *sk)
+/**
+ * tfrc_rx_hist_rtt_prev_s: previously suitable (wrt rtt_last_s) RTT-sampling entry
+ */
+static inline struct tfrc_rx_hist_entry *
+ tfrc_rx_hist_rtt_prev_s(const struct tfrc_rx_hist *h)
{
- if (tfrc_rx_hist_alloc(h))
- return -ENOBUFS;
- /*
- * Initialise first entry with GSR to start loss detection as early as
- * possible. Code using this must not use any other fields. The entry
- * will be overwritten once the CCID updates its received packets.
- */
- tfrc_rx_hist_loss_prev(h)->tfrchrx_seqno = dccp_sk(sk)->dccps_gsr;
- return 0;
+ return h->ring[h->rtt_sample_prev];
}
-EXPORT_SYMBOL_GPL(tfrc_rx_hist_init);
/**
* tfrc_rx_hist_sample_rtt - Sample RTT from timestamp / CCVal
- * Based on ideas presented in RFC 4342, 8.1. This function expects that no loss
- * is pending and uses the following history entries (via rtt_sample_prev):
- * - h->ring[0] contains the most recent history entry prior to @skb;
- * - h->ring[1] is an unused `dummy' entry when the current difference is 0;
+ * Based on ideas presented in RFC 4342, 8.1. Returns 0 if it was not able
+ * to compute a sample with given data - calling function should check this.
*/
-void tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, const struct sk_buff *skb)
+u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h, const struct sk_buff *skb)
{
- struct tfrc_rx_hist_entry *last = h->ring[0];
- u32 sample, delta_v;
-
- /*
- * When not to sample:
- * - on non-data packets
- * (RFC 4342, 8.1: CCVal only fully defined for data packets);
- * - when no data packets have been received yet
- * (FIXME: using sampled packet size as indicator here);
- * - as long as there are gaps in the sequence space (pending loss).
- */
- if (!dccp_data_packet(skb) || h->packet_size == 0 ||
- tfrc_rx_hist_loss_pending(h))
- return;
+ u32 sample = 0,
+ delta_v = SUB16(dccp_hdr(skb)->dccph_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+
+ if (delta_v < 1 || delta_v > 4) { /* unsuitable CCVal delta */
+ if (h->rtt_sample_prev == 2) { /* previous candidate stored */
+ sample = SUB16(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+ if (sample)
+ sample = 4 / sample *
+ ktime_us_delta(tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_tstamp,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp);
+ else /*
+ * FIXME: This condition is in principle not
+ * possible but occurs when CCID is used for
+ * two-way data traffic. I have tried to trace
+ * it, but the cause does not seem to be here.
+ */
+ DCCP_BUG("please report to dccp@vger.kernel.org"
+ " => prev = %u, last = %u",
+ tfrc_rx_hist_rtt_prev_s(h)->tfrchrx_ccval,
+ tfrc_rx_hist_rtt_last_s(h)->tfrchrx_ccval);
+ } else if (delta_v < 1) {
+ h->rtt_sample_prev = 1;
+ goto keep_ref_for_next_time;
+ }
- h->rtt_sample_prev = 0; /* reset previous candidate */
+ } else if (delta_v == 4) /* optimal match */
+ sample = ktime_to_us(net_timedelta(tfrc_rx_hist_rtt_last_s(h)->tfrchrx_tstamp));
+ else { /* suboptimal match */
+ h->rtt_sample_prev = 2;
+ goto keep_ref_for_next_time;
+ }
- delta_v = SUB16(dccp_hdr(skb)->dccph_ccval, last->tfrchrx_ccval);
- if (delta_v == 0) { /* less than RTT/4 difference */
- h->rtt_sample_prev = 1;
- return;
+ if (unlikely(sample > DCCP_SANE_RTT_MAX)) {
+ DCCP_WARN("RTT sample %u too large, using max\n", sample);
+ sample = DCCP_SANE_RTT_MAX;
}
- sample = dccp_sane_rtt(ktime_to_us(net_timedelta(last->tfrchrx_tstamp)));
- if (delta_v <= 4) /* between RTT/4 and RTT */
- sample *= 4 / delta_v;
- else if (!(sample < h->rtt_estimate && sample > h->rtt_estimate/2))
- /*
- * Optimisation: CCVal difference is greater than 1 RTT, yet the
- * sample is less than the local RTT estimate; which means that
- * the RTT estimate is too high.
- * To avoid noise, it is not done if the sample is below RTT/2.
- */
- return;
+ h->rtt_sample_prev = 0; /* use current entry as next reference */
+keep_ref_for_next_time:
- /* Use a lower weight than usual to increase responsiveness */
- h->rtt_estimate = tfrc_ewma(h->rtt_estimate, sample, 5);
+ return sample;
}
EXPORT_SYMBOL_GPL(tfrc_rx_hist_sample_rtt);
#include <linux/slab.h>
#include "tfrc.h"
-/**
- * tfrc_tx_hist_entry - Simple singly-linked TX history list
- * @next: next oldest entry (LIFO order)
- * @seqno: sequence number of this entry
- * @stamp: send time of packet with sequence number @seqno
- */
-struct tfrc_tx_hist_entry {
- struct tfrc_tx_hist_entry *next;
- u64 seqno;
- ktime_t stamp;
-};
-
-static inline struct tfrc_tx_hist_entry *
- tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 seqno)
-{
- while (head != NULL && head->seqno != seqno)
- head = head->next;
- return head;
-}
+struct tfrc_tx_hist_entry;
extern int tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);
+extern u32 tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head,
+ const u64 seqno, const ktime_t now);
/* Subtraction a-b modulo-16, respects circular wrap-around */
#define SUB16(a, b) (((a) + 16 - (b)) & 0xF)
* @loss_count: Number of entries in circular history
* @loss_start: Movable index (for loss detection)
* @rtt_sample_prev: Used during RTT sampling, points to candidate entry
- * @rtt_estimate: Receiver RTT estimate
- * @packet_size: Packet size in bytes (as per RFC 3448, 3.1)
- * @bytes_recvd: Number of bytes received since @bytes_start
- * @bytes_start: Start time for counting @bytes_recvd
*/
struct tfrc_rx_hist {
struct tfrc_rx_hist_entry *ring[TFRC_NDUPACK + 1];
u8 loss_count:2,
loss_start:2;
- /* Receiver RTT sampling */
#define rtt_sample_prev loss_start
- u32 rtt_estimate;
- /* Receiver sampling of application payload lengths */
- u32 packet_size,
- bytes_recvd;
- ktime_t bytes_start;
};
/**
return h->loss_count > 0;
}
-/*
- * Accessor functions to retrieve parameters sampled by the RX history
- */
-static inline u32 tfrc_rx_hist_packet_size(const struct tfrc_rx_hist *h)
-{
- if (h->packet_size == 0) {
- DCCP_WARN("No sample for s, using fallback\n");
- return TCP_MIN_RCVMSS;
- }
- return h->packet_size;
-
-}
-static inline u32 tfrc_rx_hist_rtt(const struct tfrc_rx_hist *h)
-{
- if (h->rtt_estimate == 0) {
- DCCP_WARN("No RTT estimate available, using fallback RTT\n");
- return DCCP_FALLBACK_RTT;
- }
- return h->rtt_estimate;
-}
-
-static inline void tfrc_rx_hist_restart_byte_counter(struct tfrc_rx_hist *h)
-{
- h->bytes_recvd = 0;
- h->bytes_start = ktime_get_real();
-}
-
-extern u32 tfrc_rx_hist_x_recv(struct tfrc_rx_hist *h, const u32 last_x_recv);
-
-
extern void tfrc_rx_hist_add_packet(struct tfrc_rx_hist *h,
const struct sk_buff *skb, const u64 ndp);
extern int tfrc_rx_hist_duplicate(struct tfrc_rx_hist *h, struct sk_buff *skb);
struct tfrc_loss_hist;
-extern bool tfrc_rx_congestion_event(struct tfrc_rx_hist *h,
- struct tfrc_loss_hist *lh,
- struct sk_buff *skb, const u64 ndp,
- u32 (*first_li)(struct sock *sk),
- struct sock *sk);
-extern void tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h,
- const struct sk_buff *skb);
-extern int tfrc_rx_hist_init(struct tfrc_rx_hist *h, struct sock *sk);
+extern int tfrc_rx_handle_loss(struct tfrc_rx_hist *h,
+ struct tfrc_loss_hist *lh,
+ struct sk_buff *skb, const u64 ndp,
+ u32 (*first_li)(struct sock *sk),
+ struct sock *sk);
+extern u32 tfrc_rx_hist_sample_rtt(struct tfrc_rx_hist *h,
+ const struct sk_buff *skb);
+extern int tfrc_rx_hist_alloc(struct tfrc_rx_hist *h);
extern void tfrc_rx_hist_purge(struct tfrc_rx_hist *h);
#endif /* _DCCP_PKT_HIST_ */
}
/**
- * tfrc_scaled_sqrt - Compute scaled integer sqrt(x) for 0 < x < 2^22-1
- * Uses scaling to improve accuracy of the integer approximation of sqrt(). The
- * scaling factor of 2^10 limits the maximum @sample to 4e6; this is okay for
- * clamped RTT samples (dccp_sample_rtt).
- * Should best be used for expressions of type sqrt(x)/sqrt(y), since then the
- * scaling factor is neutralised. For this purpose, it avoids returning zero.
- */
-static inline u16 tfrc_scaled_sqrt(const u32 sample)
-{
- const unsigned long non_zero_sample = sample ? : 1;
-
- return int_sqrt(non_zero_sample << 10);
-}
-
-/**
* tfrc_ewma - Exponentially weighted moving average
* @weight: Weight to be used as damping factor, in units of 1/10
*/
extern u32 tfrc_calc_x(u16 s, u32 R, u32 p);
extern u32 tfrc_calc_x_reverse_lookup(u32 fvalue);
-extern u32 tfrc_invert_loss_event_rate(u32 loss_event_rate);
extern int tfrc_tx_packet_history_init(void);
extern void tfrc_tx_packet_history_exit(void);
if (p <= TFRC_CALC_X_SPLIT) { /* 0.0000 < p <= 0.05 */
if (p < TFRC_SMALLEST_P) { /* 0.0000 < p < 0.0001 */
- /*
- * In the congestion-avoidance phase p decays towards 0
- * when there are no further losses, so this case is
- * natural. Truncating to p_min = 0.01% means that the
- * maximum achievable throughput is limited to about
- * X_calc_max = 122.4 * s/RTT (see RFC 3448, 3.1); e.g.
- * with s=1500 bytes, RTT=0.01 s: X_calc_max = 147 Mbps.
- */
- tfrc_pr_debug("Value of p (%d) below resolution. "
- "Substituting %d\n", p, TFRC_SMALLEST_P);
+ DCCP_WARN("Value of p (%d) below resolution. "
+ "Substituting %d\n", p, TFRC_SMALLEST_P);
index = 0;
} else /* 0.0001 <= p <= 0.05 */
index = p/TFRC_SMALLEST_P - 1;
result = scaled_div(s, R);
return scaled_div32(result, f);
}
+
EXPORT_SYMBOL_GPL(tfrc_calc_x);
/**
index = tfrc_binsearch(fvalue, 0);
return (index + 1) * 1000000 / TFRC_CALC_X_ARRSIZE;
}
-EXPORT_SYMBOL_GPL(tfrc_calc_x_reverse_lookup);
-/**
- * tfrc_invert_loss_event_rate - Compute p so that 10^6 corresponds to 100%
- * When @loss_event_rate is large, there is a chance that p is truncated to 0.
- * To avoid re-entering slow-start in that case, we set p = TFRC_SMALLEST_P > 0.
- */
-u32 tfrc_invert_loss_event_rate(u32 loss_event_rate)
-{
- if (loss_event_rate == UINT_MAX) /* see RFC 4342, 8.5 */
- return 0;
- if (unlikely(loss_event_rate == 0)) /* map 1/0 into 100% */
- return 1000000;
- return max_t(u32, scaled_div(1, loss_event_rate), TFRC_SMALLEST_P);
-}
-EXPORT_SYMBOL_GPL(tfrc_invert_loss_event_rate);
+EXPORT_SYMBOL_GPL(tfrc_calc_x_reverse_lookup);
extern int dccp_debug;
#define dccp_pr_debug(format, a...) DCCP_PR_DEBUG(dccp_debug, format, ##a)
#define dccp_pr_debug_cat(format, a...) DCCP_PRINTK(dccp_debug, format, ##a)
-#define dccp_debug(fmt, a...) dccp_pr_debug_cat(KERN_DEBUG fmt, ##a)
#else
#define dccp_pr_debug(format, a...)
#define dccp_pr_debug_cat(format, a...)
-#define dccp_debug(format, a...)
#endif
extern struct inet_hashinfo dccp_hashinfo;
* - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields
* Hence a safe upper bound for the maximum option length is 1020-28 = 992
*/
-#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(uint32_t))
+#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int))
#define DCCP_MAX_PACKET_HDR 28
#define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR)
#define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER)
-/* Upper bound for initial feature-negotiation overhead (padded to 32 bits) */
-#define DCCP_FEATNEG_OVERHEAD (32 * sizeof(uint32_t))
-
#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
* state, about 60 seconds */
*/
#define DCCP_RTO_MAX ((unsigned)(64 * HZ))
-/* DCCP base time resolution - 10 microseconds (RFC 4340, 13.1 ... 13.3) */
-#define DCCP_TIME_RESOLUTION 10
-
/*
* RTT sampling: sanity bounds and fallback RTT value from RFC 4340, section 3.4
*/
-#define DCCP_SANE_RTT_MIN (10 * DCCP_TIME_RESOLUTION)
+#define DCCP_SANE_RTT_MIN 100
#define DCCP_FALLBACK_RTT (USEC_PER_SEC / 5)
#define DCCP_SANE_RTT_MAX (3 * USEC_PER_SEC)
extern int sysctl_dccp_request_retries;
extern int sysctl_dccp_retries1;
extern int sysctl_dccp_retries2;
+extern int sysctl_dccp_feat_sequence_window;
+extern int sysctl_dccp_feat_rx_ccid;
+extern int sysctl_dccp_feat_tx_ccid;
+extern int sysctl_dccp_feat_ack_ratio;
+extern int sysctl_dccp_feat_send_ack_vector;
+extern int sysctl_dccp_feat_send_ndp_count;
extern int sysctl_dccp_tx_qlen;
extern int sysctl_dccp_sync_ratelimit;
extern void dccp_send_sync(struct sock *sk, const u64 seq,
const enum dccp_pkt_type pkt_type);
-/*
- * TX Packet Dequeueing Interface
- */
-extern void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb);
-extern bool dccp_qpolicy_full(struct sock *sk);
-extern void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb);
-extern struct sk_buff *dccp_qpolicy_top(struct sock *sk);
-extern struct sk_buff *dccp_qpolicy_pop(struct sock *sk);
-extern bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param);
-
-/*
- * TX Packet Output and TX Timers
- */
-extern void dccp_write_xmit(struct sock *sk);
+extern void dccp_write_xmit(struct sock *sk, int block);
extern void dccp_write_space(struct sock *sk);
-extern void dccp_flush_write_queue(struct sock *sk, long *time_budget);
extern void dccp_init_xmit_timers(struct sock *sk);
static inline void dccp_clear_xmit_timers(struct sock *sk)
extern void dccp_set_state(struct sock *sk, const int state);
extern void dccp_done(struct sock *sk);
-extern int dccp_reqsk_init(struct request_sock *rq, struct dccp_sock const *dp,
- struct sk_buff const *skb);
+extern void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb);
extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);
extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code);
extern void dccp_send_close(struct sock *sk, const int active);
extern int dccp_invalid_packet(struct sk_buff *skb);
-
-static inline u32 dccp_sane_rtt(long usec_sample)
-{
- if (unlikely(usec_sample <= 0 || usec_sample > DCCP_SANE_RTT_MAX))
- DCCP_WARN("RTT sample %ld out of bounds!\n", usec_sample);
- return clamp_val(usec_sample, DCCP_SANE_RTT_MIN, DCCP_SANE_RTT_MAX);
-}
-extern u32 dccp_sample_rtt(struct sock *sk, long delta);
+extern u32 dccp_sample_rtt(struct sock *sk, long delta);
static inline int dccp_bad_service_code(const struct sock *sk,
const __be32 service)
static inline void dccp_update_gsr(struct sock *sk, u64 seq)
{
struct dccp_sock *dp = dccp_sk(sk);
+ const struct dccp_minisock *dmsk = dccp_msk(sk);
dp->dccps_gsr = seq;
- /* Sequence validity window depends on remote Sequence Window (7.5.1) */
- dp->dccps_swl = SUB48(ADD48(dp->dccps_gsr, 1), dp->dccps_r_seq_win / 4);
- /*
- * Adjust SWL so that it is not below ISR. In contrast to RFC 4340,
- * 7.5.1 we perform this check beyond the initial handshake: W/W' are
- * always > 32, so for the first W/W' packets in the lifetime of a
- * connection we always have to adjust SWL.
- * A second reason why we are doing this is that the window depends on
- * the feature-remote value of Sequence Window: nothing stops the peer
- * from updating this value while we are busy adjusting SWL for the
- * first W packets (we would have to count from scratch again then).
- * Therefore it is safer to always make sure that the Sequence Window
- * is not artificially extended by a peer who grows SWL downwards by
- * continually updating the feature-remote Sequence-Window.
- * If sequence numbers wrap it is bad luck. But that will take a while
- * (48 bit), and this measure prevents Sequence-number attacks.
- */
- if (before48(dp->dccps_swl, dp->dccps_isr))
- dp->dccps_swl = dp->dccps_isr;
- dp->dccps_swh = ADD48(dp->dccps_gsr, (3 * dp->dccps_r_seq_win) / 4);
+ dccp_set_seqno(&dp->dccps_swl,
+ dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4));
+ dccp_set_seqno(&dp->dccps_swh,
+ dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4);
}
static inline void dccp_update_gss(struct sock *sk, u64 seq)
{
struct dccp_sock *dp = dccp_sk(sk);
- dp->dccps_gss = seq;
- /* Ack validity window depends on local Sequence Window value (7.5.1) */
- dp->dccps_awl = SUB48(ADD48(dp->dccps_gss, 1), dp->dccps_l_seq_win);
- /* Adjust AWL so that it is not below ISS - see comment above for SWL */
- if (before48(dp->dccps_awl, dp->dccps_iss))
- dp->dccps_awl = dp->dccps_iss;
- dp->dccps_awh = dp->dccps_gss;
-}
-
-static inline int dccp_ackvec_pending(const struct sock *sk)
-{
- return dccp_sk(sk)->dccps_hc_rx_ackvec != NULL &&
- !dccp_ackvec_is_empty(dccp_sk(sk)->dccps_hc_rx_ackvec);
+ dp->dccps_awh = dp->dccps_gss = seq;
+ dccp_set_seqno(&dp->dccps_awl,
+ (dp->dccps_gss -
+ dccp_msk(sk)->dccpms_sequence_window + 1));
}
static inline int dccp_ack_pending(const struct sock *sk)
{
- return dccp_ackvec_pending(sk) || inet_csk_ack_scheduled(sk);
+ const struct dccp_sock *dp = dccp_sk(sk);
+ return dp->dccps_timestamp_echo != 0 ||
+#ifdef CONFIG_IP_DCCP_ACKVEC
+ (dccp_msk(sk)->dccpms_send_ack_vector &&
+ dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
+#endif
+ inet_csk_ack_scheduled(sk);
}
-extern int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val);
-extern int dccp_feat_finalise_settings(struct dccp_sock *dp);
-extern int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq);
-extern int dccp_feat_insert_opts(struct dccp_sock*, struct dccp_request_sock*,
- struct sk_buff *skb);
-extern int dccp_feat_activate_values(struct sock *sk, struct list_head *fn);
-extern void dccp_feat_list_purge(struct list_head *fn_list);
-
extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb);
extern int dccp_insert_options_rsk(struct dccp_request_sock*, struct sk_buff*);
extern int dccp_insert_option_elapsed_time(struct sock *sk,
info->tcpi_backoff = icsk->icsk_backoff;
info->tcpi_pmtu = icsk->icsk_pmtu_cookie;
- if (dp->dccps_hc_rx_ackvec != NULL)
+ if (dccp_msk(sk)->dccpms_send_ack_vector)
info->tcpi_options |= TCPI_OPT_SACK;
ccid_hc_rx_get_info(dp->dccps_hc_rx_ccid, sk, info);
/*
* net/dccp/feat.c
*
- * Feature negotiation for the DCCP protocol (RFC 4340, section 6)
- *
- * Copyright (c) 2008 The University of Aberdeen, Scotland, UK
- * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
- * Rewrote from scratch, some bits from earlier code by
- * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
- *
+ * An implementation of the DCCP protocol
+ * Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
* ASSUMPTIONS
* -----------
- * o Feature negotiation is coordinated with connection setup (as in TCP), wild
- * changes of parameters of an established connection are not supported.
- * o Changing NN values (Ack Ratio only) is supported in state OPEN/PARTOPEN.
* o All currently known SP features have 1-byte quantities. If in the future
* extensions of RFCs 4340..42 define features with item lengths larger than
* one byte, a feature-specific extension of the code will be required.
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
+
#include <linux/module.h>
+
#include "ccid.h"
#include "feat.h"
-/* feature-specific sysctls - initialised to the defaults from RFC 4340, 6.4 */
-unsigned long sysctl_dccp_sequence_window __read_mostly = 100;
-int sysctl_dccp_rx_ccid __read_mostly = 2,
- sysctl_dccp_tx_ccid __read_mostly = 2;
+#define DCCP_FEAT_SP_NOAGREE (-123)
-/*
- * Feature activation handlers.
- *
- * These all use an u64 argument, to provide enough room for NN/SP features. At
- * this stage the negotiated values have been checked to be within their range.
- */
-static int dccp_hdlr_ccid(struct sock *sk, u64 ccid, bool rx)
+int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
+ u8 *val, u8 len, gfp_t gfp)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct ccid *new_ccid = ccid_new(ccid, sk, rx, gfp_any());
+ struct dccp_opt_pend *opt;
- if (new_ccid == NULL)
- return -ENOMEM;
+ dccp_feat_debug(type, feature, *val);
- if (rx) {
- ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
- dp->dccps_hc_rx_ccid = new_ccid;
- } else {
- ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
- dp->dccps_hc_tx_ccid = new_ccid;
+ if (len > 3) {
+ DCCP_WARN("invalid length %d\n", len);
+ return -EINVAL;
+ }
+ /* XXX add further sanity checks */
+
+ /* check if that feature is already being negotiated */
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ /* ok we found a negotiation for this option already */
+ if (opt->dccpop_feat == feature && opt->dccpop_type == type) {
+ dccp_pr_debug("Replacing old\n");
+ /* replace */
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
+ opt->dccpop_val = val;
+ opt->dccpop_len = len;
+ opt->dccpop_conf = 0;
+ return 0;
+ }
}
- return 0;
-}
-static int dccp_hdlr_seq_win(struct sock *sk, u64 seq_win, bool rx)
-{
- struct dccp_sock *dp = dccp_sk(sk);
+ /* negotiation for a new feature */
+ opt = kmalloc(sizeof(*opt), gfp);
+ if (opt == NULL)
+ return -ENOMEM;
- if (rx) {
- dp->dccps_r_seq_win = seq_win;
- /* propagate changes to update SWL/SWH */
- dccp_update_gsr(sk, dp->dccps_gsr);
- } else {
- dp->dccps_l_seq_win = seq_win;
- /* propagate changes to update AWL */
- dccp_update_gss(sk, dp->dccps_gss);
- }
- return 0;
-}
+ opt->dccpop_type = type;
+ opt->dccpop_feat = feature;
+ opt->dccpop_len = len;
+ opt->dccpop_val = val;
+ opt->dccpop_conf = 0;
+ opt->dccpop_sc = NULL;
-static int dccp_hdlr_ack_ratio(struct sock *sk, u64 ratio, bool rx)
-{
-#ifndef __CCID2_COPES_GRACEFULLY_WITH_DYNAMIC_ACK_RATIO_UPDATES__
- /*
- * FIXME: This is required until several problems in the CCID-2 code are
- * resolved. The CCID-2 code currently does not cope well; using dynamic
- * Ack Ratios greater than 1 caused instabilities. These were manifest
- * in hangups and long RTO timeouts (1...3 seconds). Until this has been
- * stabilised, it is safer not to activate dynamic Ack Ratio changes.
- */
- dccp_pr_debug("Not changing %s Ack Ratio from 1 to %u\n",
- rx ? "RX" : "TX", (u16)ratio);
- ratio = 1;
-#endif
- if (rx)
- dccp_sk(sk)->dccps_r_ack_ratio = ratio;
- else
- dccp_sk(sk)->dccps_l_ack_ratio = ratio;
+ BUG_ON(opt->dccpop_val == NULL);
+
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_pending);
return 0;
}
-static int dccp_hdlr_ackvec(struct sock *sk, u64 enable, bool rx)
+EXPORT_SYMBOL_GPL(dccp_feat_change);
+
+static int dccp_feat_update_ccid(struct sock *sk, u8 type, u8 new_ccid_nr)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ /* figure out if we are changing our CCID or the peer's */
+ const int rx = type == DCCPO_CHANGE_R;
+ const u8 ccid_nr = rx ? dmsk->dccpms_rx_ccid : dmsk->dccpms_tx_ccid;
+ struct ccid *new_ccid;
+
+ /* Check if nothing is being changed. */
+ if (ccid_nr == new_ccid_nr)
+ return 0;
+
+ new_ccid = ccid_new(new_ccid_nr, sk, rx, GFP_ATOMIC);
+ if (new_ccid == NULL)
+ return -ENOMEM;
if (rx) {
- if (enable && dp->dccps_hc_rx_ackvec == NULL) {
- dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(gfp_any());
- if (dp->dccps_hc_rx_ackvec == NULL)
- return -ENOMEM;
- } else if (!enable) {
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
- }
+ ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
+ dp->dccps_hc_rx_ccid = new_ccid;
+ dmsk->dccpms_rx_ccid = new_ccid_nr;
+ } else {
+ ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
+ dp->dccps_hc_tx_ccid = new_ccid;
+ dmsk->dccpms_tx_ccid = new_ccid_nr;
}
- return 0;
-}
-static int dccp_hdlr_ndp(struct sock *sk, u64 enable, bool rx)
-{
- if (!rx)
- dccp_sk(sk)->dccps_send_ndp_count = (enable > 0);
return 0;
}
-/*
- * Minimum Checksum Coverage is located at the RX side (9.2.1). This means that
- * `rx' holds when the sending peer informs about his partial coverage via a
- * ChangeR() option. In the other case, we are the sender and the receiver
- * announces its coverage via ChangeL() options. The policy here is to honour
- * such communication by enabling the corresponding partial coverage - but only
- * if it has not been set manually before; the warning here means that all
- * packets will be dropped.
- */
-static int dccp_hdlr_min_cscov(struct sock *sk, u64 cscov, bool rx)
+static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
{
- struct dccp_sock *dp = dccp_sk(sk);
+ dccp_feat_debug(type, feat, val);
- if (rx)
- dp->dccps_pcrlen = cscov;
- else {
- if (dp->dccps_pcslen == 0)
- dp->dccps_pcslen = cscov;
- else if (cscov > dp->dccps_pcslen)
- DCCP_WARN("CsCov %u too small, peer requires >= %u\n",
- dp->dccps_pcslen, (u8)cscov);
+ switch (feat) {
+ case DCCPF_CCID:
+ return dccp_feat_update_ccid(sk, type, val);
+ default:
+ dccp_pr_debug("UNIMPLEMENTED: %s(%d, ...)\n",
+ dccp_feat_typename(type), feat);
+ break;
}
return 0;
}
-static const struct {
- u8 feat_num; /* DCCPF_xxx */
- enum dccp_feat_type rxtx; /* RX or TX */
- enum dccp_feat_type reconciliation; /* SP or NN */
- u8 default_value; /* as in 6.4 */
- int (*activation_hdlr)(struct sock *sk, u64 val, bool rx);
-/*
- * Lookup table for location and type of features (from RFC 4340/4342)
- * +--------------------------+----+-----+----+----+---------+-----------+
- * | Feature | Location | Reconc. | Initial | Section |
- * | | RX | TX | SP | NN | Value | Reference |
- * +--------------------------+----+-----+----+----+---------+-----------+
- * | DCCPF_CCID | | X | X | | 2 | 10 |
- * | DCCPF_SHORT_SEQNOS | | X | X | | 0 | 7.6.1 |
- * | DCCPF_SEQUENCE_WINDOW | | X | | X | 100 | 7.5.2 |
- * | DCCPF_ECN_INCAPABLE | X | | X | | 0 | 12.1 |
- * | DCCPF_ACK_RATIO | | X | | X | 2 | 11.3 |
- * | DCCPF_SEND_ACK_VECTOR | X | | X | | 0 | 11.5 |
- * | DCCPF_SEND_NDP_COUNT | | X | X | | 0 | 7.7.2 |
- * | DCCPF_MIN_CSUM_COVER | X | | X | | 0 | 9.2.1 |
- * | DCCPF_DATA_CHECKSUM | X | | X | | 0 | 9.3.1 |
- * | DCCPF_SEND_LEV_RATE | X | | X | | 0 | 4342/8.4 |
- * +--------------------------+----+-----+----+----+---------+-----------+
- */
-} dccp_feat_table[] = {
- { DCCPF_CCID, FEAT_AT_TX, FEAT_SP, 2, dccp_hdlr_ccid },
- { DCCPF_SHORT_SEQNOS, FEAT_AT_TX, FEAT_SP, 0, NULL },
- { DCCPF_SEQUENCE_WINDOW, FEAT_AT_TX, FEAT_NN, 100, dccp_hdlr_seq_win },
- { DCCPF_ECN_INCAPABLE, FEAT_AT_RX, FEAT_SP, 0, NULL },
- { DCCPF_ACK_RATIO, FEAT_AT_TX, FEAT_NN, 2, dccp_hdlr_ack_ratio},
- { DCCPF_SEND_ACK_VECTOR, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_ackvec },
- { DCCPF_SEND_NDP_COUNT, FEAT_AT_TX, FEAT_SP, 0, dccp_hdlr_ndp },
- { DCCPF_MIN_CSUM_COVER, FEAT_AT_RX, FEAT_SP, 0, dccp_hdlr_min_cscov},
- { DCCPF_DATA_CHECKSUM, FEAT_AT_RX, FEAT_SP, 0, NULL },
- { DCCPF_SEND_LEV_RATE, FEAT_AT_RX, FEAT_SP, 0, NULL },
-};
-#define DCCP_FEAT_SUPPORTED_MAX ARRAY_SIZE(dccp_feat_table)
-
-/**
- * dccp_feat_index - Hash function to map feature number into array position
- * Returns consecutive array index or -1 if the feature is not understood.
- */
-static int dccp_feat_index(u8 feat_num)
+static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
+ u8 *rpref, u8 rlen)
{
- /* The first 9 entries are occupied by the types from RFC 4340, 6.4 */
- if (feat_num > DCCPF_RESERVED && feat_num <= DCCPF_DATA_CHECKSUM)
- return feat_num - 1;
+ struct dccp_sock *dp = dccp_sk(sk);
+ u8 *spref, slen, *res = NULL;
+ int i, j, rc, agree = 1;
+ BUG_ON(rpref == NULL);
+
+ /* check if we are the black sheep */
+ if (dp->dccps_role == DCCP_ROLE_CLIENT) {
+ spref = rpref;
+ slen = rlen;
+ rpref = opt->dccpop_val;
+ rlen = opt->dccpop_len;
+ } else {
+ spref = opt->dccpop_val;
+ slen = opt->dccpop_len;
+ }
/*
- * Other features: add cases for new feature types here after adding
- * them to the above table.
+ * Now we have server preference list in spref and client preference in
+ * rpref
*/
- switch (feat_num) {
- case DCCPF_SEND_LEV_RATE:
- return DCCP_FEAT_SUPPORTED_MAX - 1;
- }
- return -1;
-}
-
-static u8 dccp_feat_type(u8 feat_num)
-{
- int idx = dccp_feat_index(feat_num);
-
- if (idx < 0)
- return FEAT_UNKNOWN;
- return dccp_feat_table[idx].reconciliation;
-}
+ BUG_ON(spref == NULL);
+ BUG_ON(rpref == NULL);
-static int dccp_feat_default_value(u8 feat_num)
-{
- int idx = dccp_feat_index(feat_num);
+ /* FIXME sanity check vals */
- return idx < 0 ? : dccp_feat_table[idx].default_value;
-}
-
-/*
- * Debugging and verbose-printing section
- */
-static const char *dccp_feat_fname(const u8 feat)
-{
- static const char *feature_names[] = {
- [DCCPF_RESERVED] = "Reserved",
- [DCCPF_CCID] = "CCID",
- [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos",
- [DCCPF_SEQUENCE_WINDOW] = "Sequence Window",
- [DCCPF_ECN_INCAPABLE] = "ECN Incapable",
- [DCCPF_ACK_RATIO] = "Ack Ratio",
- [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector",
- [DCCPF_SEND_NDP_COUNT] = "Send NDP Count",
- [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage",
- [DCCPF_DATA_CHECKSUM] = "Send Data Checksum",
- };
- if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC)
- return feature_names[DCCPF_RESERVED];
-
- if (feat == DCCPF_SEND_LEV_RATE)
- return "Send Loss Event Rate";
- if (feat >= DCCPF_MIN_CCID_SPECIFIC)
- return "CCID-specific";
-
- return feature_names[feat];
-}
-
-static const char *dccp_feat_sname[] = { "DEFAULT", "INITIALISING", "CHANGING",
- "UNSTABLE", "STABLE" };
-
-#ifdef CONFIG_IP_DCCP_DEBUG
-static const char *dccp_feat_oname(const u8 opt)
-{
- switch (opt) {
- case DCCPO_CHANGE_L: return "Change_L";
- case DCCPO_CONFIRM_L: return "Confirm_L";
- case DCCPO_CHANGE_R: return "Change_R";
- case DCCPO_CONFIRM_R: return "Confirm_R";
+ /* Are values in any order? XXX Lame "algorithm" here */
+ for (i = 0; i < slen; i++) {
+ for (j = 0; j < rlen; j++) {
+ if (spref[i] == rpref[j]) {
+ res = &spref[i];
+ break;
+ }
+ }
+ if (res)
+ break;
}
- return NULL;
-}
-static void dccp_feat_printval(u8 feat_num, dccp_feat_val const *val)
-{
- u8 i, type = dccp_feat_type(feat_num);
-
- if (val == NULL || (type == FEAT_SP && val->sp.vec == NULL))
- dccp_pr_debug_cat("(NULL)");
- else if (type == FEAT_SP)
- for (i = 0; i < val->sp.len; i++)
- dccp_pr_debug_cat("%s%u", i ? " " : "", val->sp.vec[i]);
- else if (type == FEAT_NN)
- dccp_pr_debug_cat("%llu", (unsigned long long)val->nn);
- else
- dccp_pr_debug_cat("unknown type %u", type);
-}
-
-static void dccp_feat_printvals(u8 feat_num, u8 *list, u8 len)
-{
- u8 type = dccp_feat_type(feat_num);
- dccp_feat_val fval = { .sp.vec = list, .sp.len = len };
-
- if (type == FEAT_NN)
- fval.nn = dccp_decode_value_var(list, len);
- dccp_feat_printval(feat_num, &fval);
-}
+ /* we didn't agree on anything */
+ if (res == NULL) {
+ /* confirm previous value */
+ switch (opt->dccpop_feat) {
+ case DCCPF_CCID:
+ /* XXX did i get this right? =P */
+ if (opt->dccpop_type == DCCPO_CHANGE_L)
+ res = &dccp_msk(sk)->dccpms_tx_ccid;
+ else
+ res = &dccp_msk(sk)->dccpms_rx_ccid;
+ break;
-static void dccp_feat_print_entry(struct dccp_feat_entry const *entry)
-{
- dccp_debug(" * %s %s = ", entry->is_local ? "local" : "remote",
- dccp_feat_fname(entry->feat_num));
- dccp_feat_printval(entry->feat_num, &entry->val);
- dccp_pr_debug_cat(", state=%s %s\n", dccp_feat_sname[entry->state],
- entry->needs_confirm ? "(Confirm pending)" : "");
-}
+ default:
+ DCCP_BUG("Fell through, feat=%d", opt->dccpop_feat);
+ /* XXX implement res */
+ return -EFAULT;
+ }
-#define dccp_feat_print_opt(opt, feat, val, len, mandatory) do { \
- dccp_pr_debug("%s(%s, ", dccp_feat_oname(opt), dccp_feat_fname(feat));\
- dccp_feat_printvals(feat, val, len); \
- dccp_pr_debug_cat(") %s\n", mandatory ? "!" : ""); } while (0)
-
-#define dccp_feat_print_fnlist(fn_list) { \
- const struct dccp_feat_entry *___entry; \
- \
- dccp_pr_debug("List Dump:\n"); \
- list_for_each_entry(___entry, fn_list, node) \
- dccp_feat_print_entry(___entry); \
-}
-#else /* ! CONFIG_IP_DCCP_DEBUG */
-#define dccp_feat_print_opt(opt, feat, val, len, mandatory)
-#define dccp_feat_print_fnlist(fn_list)
-#endif
+ dccp_pr_debug("Don't agree... reconfirming %d\n", *res);
+ agree = 0; /* this is used for mandatory options... */
+ }
-static int __dccp_feat_activate(struct sock *sk, const int idx,
- const bool is_local, dccp_feat_val const *fval)
-{
- bool rx;
- u64 val;
+ /* need to put result and our preference list */
+ rlen = 1 + opt->dccpop_len;
+ rpref = kmalloc(rlen, GFP_ATOMIC);
+ if (rpref == NULL)
+ return -ENOMEM;
- if (idx < 0 || idx >= DCCP_FEAT_SUPPORTED_MAX)
- return -1;
- if (dccp_feat_table[idx].activation_hdlr == NULL)
- return 0;
+ *rpref = *res;
+ memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len);
- if (fval == NULL) {
- val = dccp_feat_table[idx].default_value;
- } else if (dccp_feat_table[idx].reconciliation == FEAT_SP) {
- if (fval->sp.vec == NULL) {
- /*
- * This can happen when an empty Confirm is sent
- * for an SP (i.e. known) feature. In this case
- * we would be using the default anyway.
- */
- DCCP_CRIT("Feature #%d undefined: using default", idx);
- val = dccp_feat_table[idx].default_value;
- } else {
- val = fval->sp.vec[0];
+ /* put it in the "confirm queue" */
+ if (opt->dccpop_sc == NULL) {
+ opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC);
+ if (opt->dccpop_sc == NULL) {
+ kfree(rpref);
+ return -ENOMEM;
}
} else {
- val = fval->nn;
+ /* recycle the confirm slot */
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ dccp_pr_debug("recycling confirm slot\n");
+ }
+ memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc));
+
+ opt->dccpop_sc->dccpoc_val = rpref;
+ opt->dccpop_sc->dccpoc_len = rlen;
+
+ /* update the option on our side [we are about to send the confirm] */
+ rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res);
+ if (rc) {
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ opt->dccpop_sc = NULL;
+ return rc;
}
- /* Location is RX if this is a local-RX or remote-TX feature */
- rx = (is_local == (dccp_feat_table[idx].rxtx == FEAT_AT_RX));
-
- dccp_debug(" -> activating %s %s, %sval=%llu\n", rx ? "RX" : "TX",
- dccp_feat_fname(dccp_feat_table[idx].feat_num),
- fval ? "" : "default ", (unsigned long long)val);
-
- return dccp_feat_table[idx].activation_hdlr(sk, val, rx);
-}
-
-/**
- * dccp_feat_activate - Activate feature value on socket
- * @sk: fully connected DCCP socket (after handshake is complete)
- * @feat_num: feature to activate, one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is meant
- * @fval: the value (SP or NN) to activate, or NULL to use the default value
- * For general use this function is preferable over __dccp_feat_activate().
- */
-static int dccp_feat_activate(struct sock *sk, u8 feat_num, bool local,
- dccp_feat_val const *fval)
-{
- return __dccp_feat_activate(sk, dccp_feat_index(feat_num), local, fval);
-}
-
-/* Test for "Req'd" feature (RFC 4340, 6.4) */
-static inline int dccp_feat_must_be_understood(u8 feat_num)
-{
- return feat_num == DCCPF_CCID || feat_num == DCCPF_SHORT_SEQNOS ||
- feat_num == DCCPF_SEQUENCE_WINDOW;
-}
+ dccp_pr_debug("Will confirm %d\n", *rpref);
-/* copy constructor, fval must not already contain allocated memory */
-static int dccp_feat_clone_sp_val(dccp_feat_val *fval, u8 const *val, u8 len)
-{
- fval->sp.len = len;
- if (fval->sp.len > 0) {
- fval->sp.vec = kmemdup(val, len, gfp_any());
- if (fval->sp.vec == NULL) {
- fval->sp.len = 0;
- return -ENOBUFS;
- }
+ /* say we want to change to X but we just got a confirm X, suppress our
+ * change
+ */
+ if (!opt->dccpop_conf) {
+ if (*opt->dccpop_val == *res)
+ opt->dccpop_conf = 1;
+ dccp_pr_debug("won't ask for change of same feature\n");
}
- return 0;
-}
-static void dccp_feat_val_destructor(u8 feat_num, dccp_feat_val *val)
-{
- if (unlikely(val == NULL))
- return;
- if (dccp_feat_type(feat_num) == FEAT_SP)
- kfree(val->sp.vec);
- memset(val, 0, sizeof(*val));
+ return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */
}
-static struct dccp_feat_entry *
- dccp_feat_clone_entry(struct dccp_feat_entry const *original)
+static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- struct dccp_feat_entry *new;
- u8 type = dccp_feat_type(original->feat_num);
-
- if (type == FEAT_UNKNOWN)
- return NULL;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ struct dccp_opt_pend *opt;
+ int rc = 1;
+ u8 t;
- new = kmemdup(original, sizeof(struct dccp_feat_entry), gfp_any());
- if (new == NULL)
- return NULL;
+ /*
+ * We received a CHANGE. We gotta match it against our own preference
+ * list. If we got a CHANGE_R it means it's a change for us, so we need
+ * to compare our CHANGE_L list.
+ */
+ if (type == DCCPO_CHANGE_L)
+ t = DCCPO_CHANGE_R;
+ else
+ t = DCCPO_CHANGE_L;
- if (type == FEAT_SP && dccp_feat_clone_sp_val(&new->val,
- original->val.sp.vec,
- original->val.sp.len)) {
- kfree(new);
- return NULL;
- }
- return new;
-}
+ /* find our preference list for this feature */
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (opt->dccpop_type != t || opt->dccpop_feat != feature)
+ continue;
-static void dccp_feat_entry_destructor(struct dccp_feat_entry *entry)
-{
- if (entry != NULL) {
- dccp_feat_val_destructor(entry->feat_num, &entry->val);
- kfree(entry);
+ /* find the winner from the two preference lists */
+ rc = dccp_feat_reconcile(sk, opt, val, len);
+ break;
}
-}
-/*
- * List management functions
- *
- * Feature negotiation lists rely on and maintain the following invariants:
- * - each feat_num in the list is known, i.e. we know its type and default value
- * - each feat_num/is_local combination is unique (old entries are overwritten)
- * - SP values are always freshly allocated
- * - list is sorted in increasing order of feature number (faster lookup)
- */
-static struct dccp_feat_entry *dccp_feat_list_lookup(struct list_head *fn_list,
- u8 feat_num, bool is_local)
-{
- struct dccp_feat_entry *entry;
+ /* We didn't deal with the change. This can happen if we have no
+ * preference list for the feature. In fact, it just shouldn't
+ * happen---if we understand a feature, we should have a preference list
+ * with at least the default value.
+ */
+ BUG_ON(rc == 1);
- list_for_each_entry(entry, fn_list, node)
- if (entry->feat_num == feat_num && entry->is_local == is_local)
- return entry;
- else if (entry->feat_num > feat_num)
- break;
- return NULL;
+ return rc;
}
-/**
- * dccp_feat_entry_new - Central list update routine (called by all others)
- * @head: list to add to
- * @feat: feature number
- * @local: whether the local (1) or remote feature with number @feat is meant
- * This is the only constructor and serves to ensure the above invariants.
- */
-static struct dccp_feat_entry *
- dccp_feat_entry_new(struct list_head *head, u8 feat, bool local)
+static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- struct dccp_feat_entry *entry;
-
- list_for_each_entry(entry, head, node)
- if (entry->feat_num == feat && entry->is_local == local) {
- dccp_feat_val_destructor(entry->feat_num, &entry->val);
- return entry;
- } else if (entry->feat_num > feat) {
- head = &entry->node;
- break;
- }
+ struct dccp_opt_pend *opt;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ u8 *copy;
+ int rc;
- entry = kmalloc(sizeof(*entry), gfp_any());
- if (entry != NULL) {
- entry->feat_num = feat;
- entry->is_local = local;
- list_add_tail(&entry->node, head);
+ /* NN features must be Change L (sec. 6.3.2) */
+ if (type != DCCPO_CHANGE_L) {
+ dccp_pr_debug("received %s for NN feature %d\n",
+ dccp_feat_typename(type), feature);
+ return -EFAULT;
}
- return entry;
-}
-/**
- * dccp_feat_push_change - Add/overwrite a Change option in the list
- * @fn_list: feature-negotiation list to update
- * @feat: one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is meant
- * @needs_mandatory: whether to use Mandatory feature negotiation options
- * @fval: pointer to NN/SP value to be inserted (will be copied)
- */
-static int dccp_feat_push_change(struct list_head *fn_list, u8 feat, u8 local,
- u8 mandatory, dccp_feat_val *fval)
-{
- struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local);
+ /* XXX sanity check opt val */
- if (new == NULL)
+ /* copy option so we can confirm it */
+ opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
+ if (opt == NULL)
return -ENOMEM;
- new->feat_num = feat;
- new->is_local = local;
- new->state = FEAT_INITIALISING;
- new->needs_confirm = 0;
- new->empty_confirm = 0;
- new->val = *fval;
- new->needs_mandatory = mandatory;
+ copy = kmemdup(val, len, GFP_ATOMIC);
+ if (copy == NULL) {
+ kfree(opt);
+ return -ENOMEM;
+ }
- return 0;
-}
+ opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = copy;
+ opt->dccpop_len = len;
-/**
- * dccp_feat_push_confirm - Add a Confirm entry to the FN list
- * @fn_list: feature-negotiation list to add to
- * @feat: one of %dccp_feature_numbers
- * @local: whether local (1) or remote (0) @feat_num is being confirmed
- * @fval: pointer to NN/SP value to be inserted or NULL
- * Returns 0 on success, a Reset code for further processing otherwise.
- */
-static int dccp_feat_push_confirm(struct list_head *fn_list, u8 feat, u8 local,
- dccp_feat_val *fval)
-{
- struct dccp_feat_entry *new = dccp_feat_entry_new(fn_list, feat, local);
+ /* change feature */
+ rc = dccp_feat_update(sk, type, feature, *val);
+ if (rc) {
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ return rc;
+ }
- if (new == NULL)
- return DCCP_RESET_CODE_TOO_BUSY;
+ dccp_feat_debug(type, feature, *copy);
- new->feat_num = feat;
- new->is_local = local;
- new->state = FEAT_STABLE; /* transition in 6.6.2 */
- new->needs_confirm = 1;
- new->empty_confirm = (fval == NULL);
- new->val.nn = 0; /* zeroes the whole structure */
- if (!new->empty_confirm)
- new->val = *fval;
- new->needs_mandatory = 0;
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
return 0;
}
-static int dccp_push_empty_confirm(struct list_head *fn_list, u8 feat, u8 local)
+static void dccp_feat_empty_confirm(struct dccp_minisock *dmsk,
+ u8 type, u8 feature)
{
- return dccp_feat_push_confirm(fn_list, feat, local, NULL);
-}
+ /* XXX check if other confirms for that are queued and recycle slot */
+ struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
-static inline void dccp_feat_list_pop(struct dccp_feat_entry *entry)
-{
- list_del(&entry->node);
- dccp_feat_entry_destructor(entry);
-}
-
-void dccp_feat_list_purge(struct list_head *fn_list)
-{
- struct dccp_feat_entry *entry, *next;
-
- list_for_each_entry_safe(entry, next, fn_list, node)
- dccp_feat_entry_destructor(entry);
- INIT_LIST_HEAD(fn_list);
-}
-EXPORT_SYMBOL_GPL(dccp_feat_list_purge);
-
-/* generate @to as full clone of @from - @to must not contain any nodes */
-int dccp_feat_clone_list(struct list_head const *from, struct list_head *to)
-{
- struct dccp_feat_entry *entry, *new;
-
- INIT_LIST_HEAD(to);
- list_for_each_entry(entry, from, node) {
- new = dccp_feat_clone_entry(entry);
- if (new == NULL)
- goto cloning_failed;
- list_add_tail(&new->node, to);
+ if (opt == NULL) {
+ /* XXX what do we do? Ignoring should be fine. It's a change
+ * after all =P
+ */
+ return;
}
- return 0;
-cloning_failed:
- dccp_feat_list_purge(to);
- return -ENOMEM;
-}
+ switch (type) {
+ case DCCPO_CHANGE_L:
+ opt->dccpop_type = DCCPO_CONFIRM_R;
+ break;
+ case DCCPO_CHANGE_R:
+ opt->dccpop_type = DCCPO_CONFIRM_L;
+ break;
+ default:
+ DCCP_WARN("invalid type %d\n", type);
+ kfree(opt);
+ return;
+ }
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = NULL;
+ opt->dccpop_len = 0;
-/**
- * dccp_feat_valid_nn_length - Enforce length constraints on NN options
- * Length is between 0 and %DCCP_OPTVAL_MAXLEN. Used for outgoing packets only,
- * incoming options are accepted as long as their values are valid.
- */
-static u8 dccp_feat_valid_nn_length(u8 feat_num)
-{
- if (feat_num == DCCPF_ACK_RATIO) /* RFC 4340, 11.3 and 6.6.8 */
- return 2;
- if (feat_num == DCCPF_SEQUENCE_WINDOW) /* RFC 4340, 7.5.2 and 6.5 */
- return 6;
- return 0;
-}
+ /* change feature */
+ dccp_pr_debug("Empty %s(%d)\n", dccp_feat_typename(type), feature);
-static u8 dccp_feat_is_valid_nn_val(u8 feat_num, u64 val)
-{
- switch (feat_num) {
- case DCCPF_ACK_RATIO:
- return val <= DCCPF_ACK_RATIO_MAX;
- case DCCPF_SEQUENCE_WINDOW:
- return val >= DCCPF_SEQ_WMIN && val <= DCCPF_SEQ_WMAX;
- }
- return 0; /* feature unknown - so we can't tell */
+ list_add_tail(&opt->dccpop_node, &dmsk->dccpms_conf);
}
-/* check that SP values are within the ranges defined in RFC 4340 */
-static u8 dccp_feat_is_valid_sp_val(u8 feat_num, u8 val)
+static void dccp_feat_flush_confirm(struct sock *sk)
{
- switch (feat_num) {
- case DCCPF_CCID:
- return val == DCCPC_CCID2 || val == DCCPC_CCID3;
- /* Type-check Boolean feature values: */
- case DCCPF_SHORT_SEQNOS:
- case DCCPF_ECN_INCAPABLE:
- case DCCPF_SEND_ACK_VECTOR:
- case DCCPF_SEND_NDP_COUNT:
- case DCCPF_DATA_CHECKSUM:
- case DCCPF_SEND_LEV_RATE:
- return val < 2;
- case DCCPF_MIN_CSUM_COVER:
- return val < 16;
- }
- return 0; /* feature unknown */
-}
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ /* Check if there is anything to confirm in the first place */
+ int yes = !list_empty(&dmsk->dccpms_conf);
-static u8 dccp_feat_sp_list_ok(u8 feat_num, u8 const *sp_list, u8 sp_len)
-{
- if (sp_list == NULL || sp_len < 1)
- return 0;
- while (sp_len--)
- if (!dccp_feat_is_valid_sp_val(feat_num, *sp_list++))
- return 0;
- return 1;
-}
+ if (!yes) {
+ struct dccp_opt_pend *opt;
-/**
- * dccp_feat_insert_opts - Generate FN options from current list state
- * @skb: next sk_buff to be sent to the peer
- * @dp: for client during handshake and general negotiation
- * @dreq: used by the server only (all Changes/Confirms in LISTEN/RESPOND)
- */
-int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq,
- struct sk_buff *skb)
-{
- struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg;
- struct dccp_feat_entry *pos, *next;
- u8 opt, type, len, *ptr, nn_in_nbo[DCCP_OPTVAL_MAXLEN];
- bool rpt;
-
- /* put entries into @skb in the order they appear in the list */
- list_for_each_entry_safe_reverse(pos, next, fn, node) {
- opt = dccp_feat_genopt(pos);
- type = dccp_feat_type(pos->feat_num);
- rpt = false;
-
- if (pos->empty_confirm) {
- len = 0;
- ptr = NULL;
- } else {
- if (type == FEAT_SP) {
- len = pos->val.sp.len;
- ptr = pos->val.sp.vec;
- rpt = pos->needs_confirm;
- } else if (type == FEAT_NN) {
- len = dccp_feat_valid_nn_length(pos->feat_num);
- ptr = nn_in_nbo;
- dccp_encode_value_var(pos->val.nn, ptr, len);
- } else {
- DCCP_BUG("unknown feature %u", pos->feat_num);
- return -1;
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (opt->dccpop_conf) {
+ yes = 1;
+ break;
}
}
- dccp_feat_print_opt(opt, pos->feat_num, ptr, len, 0);
-
- if (dccp_insert_fn_opt(skb, opt, pos->feat_num, ptr, len, rpt))
- return -1;
- if (pos->needs_mandatory && dccp_insert_option_mandatory(skb))
- return -1;
- /*
- * Enter CHANGING after transmitting the Change option (6.6.2).
- */
- if (pos->state == FEAT_INITIALISING)
- pos->state = FEAT_CHANGING;
}
- return 0;
-}
-
-/**
- * __feat_register_nn - Register new NN value on socket
- * @fn: feature-negotiation list to register with
- * @feat: an NN feature from %dccp_feature_numbers
- * @mandatory: use Mandatory option if 1
- * @nn_val: value to register (restricted to 4 bytes)
- * Note that NN features are local by definition (RFC 4340, 6.3.2).
- */
-static int __feat_register_nn(struct list_head *fn, u8 feat,
- u8 mandatory, u64 nn_val)
-{
- dccp_feat_val fval = { .nn = nn_val };
-
- if (dccp_feat_type(feat) != FEAT_NN ||
- !dccp_feat_is_valid_nn_val(feat, nn_val))
- return -EINVAL;
-
- /* Don't bother with default values, they will be activated anyway. */
- if (nn_val - (u64)dccp_feat_default_value(feat) == 0)
- return 0;
-
- return dccp_feat_push_change(fn, feat, 1, mandatory, &fval);
-}
-
-/**
- * __feat_register_sp - Register new SP value/list on socket
- * @fn: feature-negotiation list to register with
- * @feat: an SP feature from %dccp_feature_numbers
- * @is_local: whether the local (1) or the remote (0) @feat is meant
- * @mandatory: use Mandatory option if 1
- * @sp_val: SP value followed by optional preference list
- * @sp_len: length of @sp_val in bytes
- */
-static int __feat_register_sp(struct list_head *fn, u8 feat, u8 is_local,
- u8 mandatory, u8 const *sp_val, u8 sp_len)
-{
- dccp_feat_val fval;
- if (dccp_feat_type(feat) != FEAT_SP ||
- !dccp_feat_sp_list_ok(feat, sp_val, sp_len))
- return -EINVAL;
-
- /* Avoid negotiating alien CCIDs by only advertising supported ones */
- if (feat == DCCPF_CCID && !ccid_support_check(sp_val, sp_len))
- return -EOPNOTSUPP;
-
- if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len))
- return -ENOMEM;
+ if (!yes)
+ return;
- return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
+ /* OK there is something to confirm... */
+ /* XXX check if packet is in flight? Send delayed ack?? */
+ if (sk->sk_state == DCCP_OPEN)
+ dccp_send_ack(sk);
}
-/**
- * dccp_feat_register_sp - Register requests to change SP feature values
- * @sk: client or listening socket
- * @feat: one of %dccp_feature_numbers
- * @is_local: whether the local (1) or remote (0) @feat is meant
- * @list: array of preferred values, in descending order of preference
- * @len: length of @list in bytes
- */
-int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local,
- u8 const *list, u8 len)
-{ /* any changes must be registered before establishing the connection */
- if (sk->sk_state != DCCP_CLOSED)
- return -EISCONN;
- if (dccp_feat_type(feat) != FEAT_SP)
- return -EINVAL;
- return __feat_register_sp(&dccp_sk(sk)->dccps_featneg, feat, is_local,
- 0, list, len);
-}
-
-/* Analogous to dccp_feat_register_sp(), but for non-negotiable values */
-int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val)
+int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
{
- /* any changes must be registered before establishing the connection */
- if (sk->sk_state != DCCP_CLOSED)
- return -EISCONN;
- if (dccp_feat_type(feat) != FEAT_NN)
- return -EINVAL;
- return __feat_register_nn(&dccp_sk(sk)->dccps_featneg, feat, 0, val);
-}
+ int rc;
-/**
- * dccp_feat_signal_nn_change - Update NN values for an established connection
- * @sk: DCCP socket of an established connection
- * @feat: NN feature number from %dccp_feature_numbers
- * @nn_val: the new value to use
- * This function is used to communicate NN updates out-of-band. The difference
- * to feature negotiation during connection setup is that values are activated
- * immediately after validation, i.e. we don't wait for the Confirm: either the
- * value is accepted by the peer (and then the waiting is futile), or it is not
- * (Reset or empty Confirm). We don't accept empty Confirms - transmitted values
- * are validated, and the peer "MUST accept any valid value" (RFC 4340, 6.3.2).
- */
-int dccp_feat_signal_nn_change(struct sock *sk, u8 feat, u64 nn_val)
-{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- dccp_feat_val fval = { .nn = nn_val };
- struct dccp_feat_entry *entry;
+ dccp_feat_debug(type, feature, *val);
- if (sk->sk_state != DCCP_OPEN && sk->sk_state != DCCP_PARTOPEN)
- return 0;
+ /* figure out if it's SP or NN feature */
+ switch (feature) {
+ /* deal with SP features */
+ case DCCPF_CCID:
+ rc = dccp_feat_sp(sk, type, feature, val, len);
+ break;
- if (dccp_feat_type(feat) != FEAT_NN ||
- !dccp_feat_is_valid_nn_val(feat, nn_val))
- return -EINVAL;
+ /* deal with NN features */
+ case DCCPF_ACK_RATIO:
+ rc = dccp_feat_nn(sk, type, feature, val, len);
+ break;
- entry = dccp_feat_list_lookup(fn, feat, 1);
- if (entry != NULL) {
- dccp_pr_debug("Ignoring %llu, entry %llu exists in state %s\n",
- (unsigned long long)nn_val,
- (unsigned long long)entry->val.nn,
- dccp_feat_sname[entry->state]);
- return 0;
+ /* XXX implement other features */
+ default:
+ dccp_pr_debug("UNIMPLEMENTED: not handling %s(%d, ...)\n",
+ dccp_feat_typename(type), feature);
+ rc = -EFAULT;
+ break;
}
- if (dccp_feat_activate(sk, feat, 1, &fval))
- return -EADV;
-
- inet_csk_schedule_ack(sk);
- return dccp_feat_push_change(fn, feat, 1, 0, &fval);
-}
-EXPORT_SYMBOL_GPL(dccp_feat_signal_nn_change);
-
-/*
- * Tracking features whose value depend on the choice of CCID
- *
- * This is designed with an extension in mind so that a list walk could be done
- * before activating any features. However, the existing framework was found to
- * work satisfactorily up until now, the automatic verification is left open.
- * When adding new CCIDs, add a corresponding dependency table here.
- */
-static const struct ccid_dependency *dccp_feat_ccid_deps(u8 ccid, bool is_local)
-{
- static const struct ccid_dependency ccid2_dependencies[2][2] = {
- /*
- * CCID2 mandates Ack Vectors (RFC 4341, 4.): as CCID is a TX
- * feature and Send Ack Vector is an RX feature, `is_local'
- * needs to be reversed.
+ /* check if there were problems changing features */
+ if (rc) {
+ /* If we don't agree on SP, we sent a confirm for old value.
+ * However we propagate rc to caller in case option was
+ * mandatory
*/
- { /* Dependencies of the receiver-side (remote) CCID2 */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = true,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 }
- },
- { /* Dependencies of the sender-side (local) CCID2 */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 }
- }
- };
- static const struct ccid_dependency ccid3_dependencies[2][5] = {
- { /*
- * Dependencies of the receiver-side CCID3
- */
- { /* locally disable Ack Vectors */
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = true,
- .is_mandatory = false,
- .val = 0
- },
- { /* see below why Send Loss Event Rate is on */
- .dependent_feat = DCCPF_SEND_LEV_RATE,
- .is_local = true,
- .is_mandatory = true,
- .val = 1
- },
- { /* NDP Count is needed as per RFC 4342, 6.1.1 */
- .dependent_feat = DCCPF_SEND_NDP_COUNT,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { 0, 0, 0, 0 },
- },
- { /*
- * CCID3 at the TX side: we request that the HC-receiver
- * will not send Ack Vectors (they will be ignored, so
- * Mandatory is not set); we enable Send Loss Event Rate
- * (Mandatory since the implementation does not support
- * the Loss Intervals option of RFC 4342, 8.6).
- * The last two options are for peer's information only.
- */
- {
- .dependent_feat = DCCPF_SEND_ACK_VECTOR,
- .is_local = false,
- .is_mandatory = false,
- .val = 0
- },
- {
- .dependent_feat = DCCPF_SEND_LEV_RATE,
- .is_local = false,
- .is_mandatory = true,
- .val = 1
- },
- { /* this CCID does not support Ack Ratio */
- .dependent_feat = DCCPF_ACK_RATIO,
- .is_local = true,
- .is_mandatory = false,
- .val = 0
- },
- { /* tell receiver we are sending NDP counts */
- .dependent_feat = DCCPF_SEND_NDP_COUNT,
- .is_local = true,
- .is_mandatory = false,
- .val = 1
- },
- { 0, 0, 0, 0 }
- }
- };
- switch (ccid) {
- case DCCPC_CCID2:
- return ccid2_dependencies[is_local];
- case DCCPC_CCID3:
- return ccid3_dependencies[is_local];
- default:
- return NULL;
+ if (rc != DCCP_FEAT_SP_NOAGREE)
+ dccp_feat_empty_confirm(dccp_msk(sk), type, feature);
}
-}
-/**
- * dccp_feat_propagate_ccid - Resolve dependencies of features on choice of CCID
- * @fn: feature-negotiation list to update
- * @id: CCID number to track
- * @is_local: whether TX CCID (1) or RX CCID (0) is meant
- * This function needs to be called after registering all other features.
- */
-static int dccp_feat_propagate_ccid(struct list_head *fn, u8 id, bool is_local)
-{
- const struct ccid_dependency *table = dccp_feat_ccid_deps(id, is_local);
- int i, rc = (table == NULL);
-
- for (i = 0; rc == 0 && table[i].dependent_feat != DCCPF_RESERVED; i++)
- if (dccp_feat_type(table[i].dependent_feat) == FEAT_SP)
- rc = __feat_register_sp(fn, table[i].dependent_feat,
- table[i].is_local,
- table[i].is_mandatory,
- &table[i].val, 1);
- else
- rc = __feat_register_nn(fn, table[i].dependent_feat,
- table[i].is_mandatory,
- table[i].val);
- return rc;
-}
-
-/**
- * dccp_feat_finalise_settings - Finalise settings before starting negotiation
- * @dp: client or listening socket (settings will be inherited)
- * This is called after all registrations (socket initialisation, sysctls, and
- * sockopt calls), and before sending the first packet containing Change options
- * (ie. client-Request or server-Response), to ensure internal consistency.
- */
-int dccp_feat_finalise_settings(struct dccp_sock *dp)
-{
- struct list_head *fn = &dp->dccps_featneg;
- struct dccp_feat_entry *entry;
- int i = 2, ccids[2] = { -1, -1 };
+ /* generate the confirm [if required] */
+ dccp_feat_flush_confirm(sk);
- /*
- * Propagating CCIDs:
- * 1) not useful to propagate CCID settings if this host advertises more
- * than one CCID: the choice of CCID may still change - if this is
- * the client, or if this is the server and the client sends
- * singleton CCID values.
- * 2) since is that propagate_ccid changes the list, we defer changing
- * the sorted list until after the traversal.
- */
- list_for_each_entry(entry, fn, node)
- if (entry->feat_num == DCCPF_CCID && entry->val.sp.len == 1)
- ccids[entry->is_local] = entry->val.sp.vec[0];
- while (i--)
- if (ccids[i] > 0 && dccp_feat_propagate_ccid(fn, ccids[i], i))
- return -1;
- dccp_feat_print_fnlist(fn);
- return 0;
+ return rc;
}
-/**
- * dccp_feat_server_ccid_dependencies - Resolve CCID-dependent features
- * It is the server which resolves the dependencies once the CCID has been
- * fully negotiated. If no CCID has been negotiated, it uses the default CCID.
- */
-int dccp_feat_server_ccid_dependencies(struct dccp_request_sock *dreq)
-{
- struct list_head *fn = &dreq->dreq_featneg;
- struct dccp_feat_entry *entry;
- u8 is_local, ccid;
-
- for (is_local = 0; is_local <= 1; is_local++) {
- entry = dccp_feat_list_lookup(fn, DCCPF_CCID, is_local);
-
- if (entry != NULL && !entry->empty_confirm)
- ccid = entry->val.sp.vec[0];
- else
- ccid = dccp_feat_default_value(DCCPF_CCID);
-
- if (dccp_feat_propagate_ccid(fn, ccid, is_local))
- return -1;
- }
- return 0;
-}
+EXPORT_SYMBOL_GPL(dccp_feat_change_recv);
-/* Select the first entry in @servlist that also occurs in @clilist (6.3.1) */
-static int dccp_feat_preflist_match(u8 *servlist, u8 slen, u8 *clilist, u8 clen)
+int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len)
{
- u8 c, s;
+ u8 t;
+ struct dccp_opt_pend *opt;
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ int found = 0;
+ int all_confirmed = 1;
- for (s = 0; s < slen; s++)
- for (c = 0; c < clen; c++)
- if (servlist[s] == clilist[c])
- return servlist[s];
- return -1;
-}
+ dccp_feat_debug(type, feature, *val);
-/**
- * dccp_feat_prefer - Move preferred entry to the start of array
- * Reorder the @array_len elements in @array so that @preferred_value comes
- * first. Returns >0 to indicate that @preferred_value does occur in @array.
- */
-static u8 dccp_feat_prefer(u8 preferred_value, u8 *array, u8 array_len)
-{
- u8 i, does_occur = 0;
+ /* locate our change request */
+ switch (type) {
+ case DCCPO_CONFIRM_L: t = DCCPO_CHANGE_R; break;
+ case DCCPO_CONFIRM_R: t = DCCPO_CHANGE_L; break;
+ default: DCCP_WARN("invalid type %d\n", type);
+ return 1;
- if (array != NULL) {
- for (i = 0; i < array_len; i++)
- if (array[i] == preferred_value) {
- array[i] = array[0];
- does_occur++;
- }
- if (does_occur)
- array[0] = preferred_value;
}
- return does_occur;
-}
+ /* XXX sanity check feature value */
-/**
- * dccp_feat_reconcile - Reconcile SP preference lists
- * @fval: SP list to reconcile into
- * @arr: received SP preference list
- * @len: length of @arr in bytes
- * @is_server: whether this side is the server (and @fv is the server's list)
- * @reorder: whether to reorder the list in @fv after reconciling with @arr
- * When successful, > 0 is returned and the reconciled list is in @fval.
- * A value of 0 means that negotiation failed (no shared entry).
- */
-static int dccp_feat_reconcile(dccp_feat_val *fv, u8 *arr, u8 len,
- bool is_server, bool reorder)
-{
- int rc;
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ if (!opt->dccpop_conf && opt->dccpop_type == t &&
+ opt->dccpop_feat == feature) {
+ found = 1;
+ dccp_pr_debug("feature %d found\n", opt->dccpop_feat);
- if (!fv->sp.vec || !arr) {
- DCCP_CRIT("NULL feature value or array");
- return 0;
- }
+ /* XXX do sanity check */
- if (is_server)
- rc = dccp_feat_preflist_match(fv->sp.vec, fv->sp.len, arr, len);
- else
- rc = dccp_feat_preflist_match(arr, len, fv->sp.vec, fv->sp.len);
-
- if (!reorder)
- return rc;
- if (rc < 0)
- return 0;
+ opt->dccpop_conf = 1;
- /*
- * Reorder list: used for activating features and in dccp_insert_fn_opt.
- */
- return dccp_feat_prefer(rc, fv->sp.vec, fv->sp.len);
-}
+ /* We got a confirmation---change the option */
+ dccp_feat_update(sk, opt->dccpop_type,
+ opt->dccpop_feat, *val);
-/**
- * dccp_feat_change_recv - Process incoming ChangeL/R options
- * @fn: feature-negotiation list to update
- * @is_mandatory: whether the Change was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L or %DCCPO_CHANGE_R
- * @feat: one of %dccp_feature_numbers
- * @val: NN value or SP value/preference list
- * @len: length of @val in bytes
- * @server: whether this node is the server (1) or the client (0)
- */
-static u8 dccp_feat_change_recv(struct list_head *fn, u8 is_mandatory, u8 opt,
- u8 feat, u8 *val, u8 len, const bool server)
-{
- u8 defval, type = dccp_feat_type(feat);
- const bool local = (opt == DCCPO_CHANGE_R);
- struct dccp_feat_entry *entry;
- dccp_feat_val fval;
-
- if (len == 0 || type == FEAT_UNKNOWN) /* 6.1 and 6.6.8 */
- goto unknown_feature_or_value;
-
- dccp_feat_print_opt(opt, feat, val, len, is_mandatory);
-
- /*
- * Negotiation of NN features: Change R is invalid, so there is no
- * simultaneous negotiation; hence we do not look up in the list.
- */
- if (type == FEAT_NN) {
- if (local || len > sizeof(fval.nn))
- goto unknown_feature_or_value;
-
- /* 6.3.2: "The feature remote MUST accept any valid value..." */
- fval.nn = dccp_decode_value_var(val, len);
- if (!dccp_feat_is_valid_nn_val(feat, fval.nn))
- goto unknown_feature_or_value;
+ /* XXX check the return value of dccp_feat_update */
+ break;
+ }
- return dccp_feat_push_confirm(fn, feat, local, &fval);
+ if (!opt->dccpop_conf)
+ all_confirmed = 0;
}
- /*
- * Unidirectional/simultaneous negotiation of SP features (6.3.1)
+ /* fix re-transmit timer */
+ /* XXX gotta make sure that no option negotiation occurs during
+ * connection shutdown. Consider that the CLOSEREQ is sent and timer is
+ * on. if all options are confirmed it might kill timer which should
+ * remain alive until close is received.
*/
- entry = dccp_feat_list_lookup(fn, feat, local);
- if (entry == NULL) {
- /*
- * No particular preferences have been registered. We deal with
- * this situation by assuming that all valid values are equally
- * acceptable, and apply the following checks:
- * - if the peer's list is a singleton, we accept a valid value;
- * - if we are the server, we first try to see if the peer (the
- * client) advertises the default value. If yes, we use it,
- * otherwise we accept the preferred value;
- * - else if we are the client, we use the first list element.
- */
- if (dccp_feat_clone_sp_val(&fval, val, 1))
- return DCCP_RESET_CODE_TOO_BUSY;
-
- if (len > 1 && server) {
- defval = dccp_feat_default_value(feat);
- if (dccp_feat_preflist_match(&defval, 1, val, len) > -1)
- fval.sp.vec[0] = defval;
- } else if (!dccp_feat_is_valid_sp_val(feat, fval.sp.vec[0])) {
- kfree(fval.sp.vec);
- goto unknown_feature_or_value;
- }
-
- /* Treat unsupported CCIDs like invalid values */
- if (feat == DCCPF_CCID && !ccid_support_check(fval.sp.vec, 1)) {
- kfree(fval.sp.vec);
- goto not_valid_or_not_known;
- }
-
- return dccp_feat_push_confirm(fn, feat, local, &fval);
-
- } else if (entry->state == FEAT_UNSTABLE) { /* 6.6.2 */
- return 0;
+ if (all_confirmed) {
+ dccp_pr_debug("clear feat negotiation timer %p\n", sk);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
}
- if (dccp_feat_reconcile(&entry->val, val, len, server, true)) {
- entry->empty_confirm = 0;
- } else if (is_mandatory) {
- return DCCP_RESET_CODE_MANDATORY_ERROR;
- } else if (entry->state == FEAT_INITIALISING) {
- /*
- * Failed simultaneous negotiation (server only): try to `save'
- * the connection by checking whether entry contains the default
- * value for @feat. If yes, send an empty Confirm to signal that
- * the received Change was not understood - which implies using
- * the default value.
- * If this also fails, we use Reset as the last resort.
- */
- WARN_ON(!server);
- defval = dccp_feat_default_value(feat);
- if (!dccp_feat_reconcile(&entry->val, &defval, 1, server, true))
- return DCCP_RESET_CODE_OPTION_ERROR;
- entry->empty_confirm = 1;
- }
- entry->needs_confirm = 1;
- entry->needs_mandatory = 0;
- entry->state = FEAT_STABLE;
+ if (!found)
+ dccp_pr_debug("%s(%d, ...) never requested\n",
+ dccp_feat_typename(type), feature);
return 0;
-
-unknown_feature_or_value:
- if (!is_mandatory)
- return dccp_push_empty_confirm(fn, feat, local);
-
-not_valid_or_not_known:
- return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
}
-/**
- * dccp_feat_confirm_recv - Process received Confirm options
- * @fn: feature-negotiation list to update
- * @is_mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CONFIRM_L or %DCCPO_CONFIRM_R
- * @feat: one of %dccp_feature_numbers
- * @val: NN value or SP value/preference list
- * @len: length of @val in bytes
- * @server: whether this node is server (1) or client (0)
- */
-static u8 dccp_feat_confirm_recv(struct list_head *fn, u8 is_mandatory, u8 opt,
- u8 feat, u8 *val, u8 len, const bool server)
-{
- u8 *plist, plen, type = dccp_feat_type(feat);
- const bool local = (opt == DCCPO_CONFIRM_R);
- struct dccp_feat_entry *entry = dccp_feat_list_lookup(fn, feat, local);
-
- dccp_feat_print_opt(opt, feat, val, len, is_mandatory);
-
- if (entry == NULL) { /* nothing queued: ignore or handle error */
- if (is_mandatory && type == FEAT_UNKNOWN)
- return DCCP_RESET_CODE_MANDATORY_ERROR;
-
- if (!local && type == FEAT_NN) /* 6.3.2 */
- goto confirmation_failed;
- return 0;
- }
-
- if (entry->state != FEAT_CHANGING) /* 6.6.2 */
- return 0;
-
- if (len == 0) {
- if (dccp_feat_must_be_understood(feat)) /* 6.6.7 */
- goto confirmation_failed;
- /*
- * Empty Confirm during connection setup: this means reverting
- * to the `old' value, which in this case is the default. Since
- * we handle default values automatically when no other values
- * have been set, we revert to the old value by removing this
- * entry from the list.
- */
- dccp_feat_list_pop(entry);
- return 0;
- }
+EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv);
- if (type == FEAT_NN) {
- if (len > sizeof(entry->val.nn))
- goto confirmation_failed;
+void dccp_feat_clean(struct dccp_minisock *dmsk)
+{
+ struct dccp_opt_pend *opt, *next;
- if (entry->val.nn == dccp_decode_value_var(val, len))
- goto confirmation_succeeded;
+ list_for_each_entry_safe(opt, next, &dmsk->dccpms_pending,
+ dccpop_node) {
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
- DCCP_WARN("Bogus Confirm for non-existing value\n");
- goto confirmation_failed;
- }
+ if (opt->dccpop_sc != NULL) {
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ }
- /*
- * Parsing SP Confirms: the first element of @val is the preferred
- * SP value which the peer confirms, the remainder depends on @len.
- * Note that only the confirmed value need to be a valid SP value.
- */
- if (!dccp_feat_is_valid_sp_val(feat, *val))
- goto confirmation_failed;
-
- if (len == 1) { /* peer didn't supply a preference list */
- plist = val;
- plen = len;
- } else { /* preferred value + preference list */
- plist = val + 1;
- plen = len - 1;
+ kfree(opt);
}
+ INIT_LIST_HEAD(&dmsk->dccpms_pending);
- /* Check whether the peer got the reconciliation right (6.6.8) */
- if (dccp_feat_reconcile(&entry->val, plist, plen, server, 0) != *val) {
- DCCP_WARN("Confirm selected the wrong value %u\n", *val);
- return DCCP_RESET_CODE_OPTION_ERROR;
+ list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
+ BUG_ON(opt == NULL);
+ if (opt->dccpop_val != NULL)
+ kfree(opt->dccpop_val);
+ kfree(opt);
}
- entry->val.sp.vec[0] = *val;
-
-confirmation_succeeded:
- entry->state = FEAT_STABLE;
- return 0;
-
-confirmation_failed:
- DCCP_WARN("Confirmation failed\n");
- return is_mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
}
-/**
- * dccp_feat_handle_nn_established - Fast-path reception of NN options
- * @sk: socket of an established DCCP connection
- * @mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L | %DCCPO_CONFIRM_R (NN only)
- * @feat: NN number, one of %dccp_feature_numbers
- * @val: NN value
- * @len: length of @val in bytes
- * This function combines the functionality of change_recv/confirm_recv, with
- * the following differences (reset codes are the same):
- * - cleanup after receiving the Confirm;
- * - values are directly activated after successful parsing;
- * - deliberately restricted to NN features.
- * The restriction to NN features is essential since SP features can have non-
- * predictable outcomes (depending on the remote configuration), and are inter-
- * dependent (CCIDs for instance cause further dependencies).
+EXPORT_SYMBOL_GPL(dccp_feat_clean);
+
+/* this is to be called only when a listening sock creates its child. It is
+ * assumed by the function---the confirm is not duplicated, but rather it is
+ * "passed on".
*/
-static u8 dccp_feat_handle_nn_established(struct sock *sk, u8 mandatory, u8 opt,
- u8 feat, u8 *val, u8 len)
+int dccp_feat_clone(struct sock *oldsk, struct sock *newsk)
{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- const bool local = (opt == DCCPO_CONFIRM_R);
- struct dccp_feat_entry *entry;
- u8 type = dccp_feat_type(feat);
- dccp_feat_val fval;
+ struct dccp_minisock *olddmsk = dccp_msk(oldsk);
+ struct dccp_minisock *newdmsk = dccp_msk(newsk);
+ struct dccp_opt_pend *opt;
+ int rc = 0;
- dccp_feat_print_opt(opt, feat, val, len, mandatory);
+ INIT_LIST_HEAD(&newdmsk->dccpms_pending);
+ INIT_LIST_HEAD(&newdmsk->dccpms_conf);
- /* Ignore non-mandatory unknown and non-NN features */
- if (type == FEAT_UNKNOWN) {
- if (local && !mandatory)
- return 0;
- goto fast_path_unknown;
- } else if (type != FEAT_NN) {
- return 0;
- }
-
- /*
- * We don't accept empty Confirms, since in fast-path feature
- * negotiation the values are enabled immediately after sending
- * the Change option.
- * Empty Changes on the other hand are invalid (RFC 4340, 6.1).
- */
- if (len == 0 || len > sizeof(fval.nn))
- goto fast_path_unknown;
-
- if (opt == DCCPO_CHANGE_L) {
- fval.nn = dccp_decode_value_var(val, len);
- if (!dccp_feat_is_valid_nn_val(feat, fval.nn))
- goto fast_path_unknown;
+ list_for_each_entry(opt, &olddmsk->dccpms_pending, dccpop_node) {
+ struct dccp_opt_pend *newopt;
+ /* copy the value of the option */
+ u8 *val = kmemdup(opt->dccpop_val, opt->dccpop_len, GFP_ATOMIC);
- if (dccp_feat_push_confirm(fn, feat, local, &fval) ||
- dccp_feat_activate(sk, feat, local, &fval))
- return DCCP_RESET_CODE_TOO_BUSY;
+ if (val == NULL)
+ goto out_clean;
- /* set the `Ack Pending' flag to piggyback a Confirm */
- inet_csk_schedule_ack(sk);
-
- } else if (opt == DCCPO_CONFIRM_R) {
- entry = dccp_feat_list_lookup(fn, feat, local);
- if (entry == NULL || entry->state != FEAT_CHANGING)
- return 0;
-
- fval.nn = dccp_decode_value_var(val, len);
- if (fval.nn != entry->val.nn) {
- DCCP_WARN("Bogus Confirm for non-existing value\n");
- goto fast_path_failed;
+ newopt = kmemdup(opt, sizeof(*newopt), GFP_ATOMIC);
+ if (newopt == NULL) {
+ kfree(val);
+ goto out_clean;
}
- /* It has been confirmed - so remove the entry */
- dccp_feat_list_pop(entry);
+ /* insert the option */
+ newopt->dccpop_val = val;
+ list_add_tail(&newopt->dccpop_node, &newdmsk->dccpms_pending);
- } else {
- DCCP_WARN("Received illegal option %u\n", opt);
- goto fast_path_failed;
+ /* XXX what happens with backlogs and multiple connections at
+ * once...
+ */
+ /* the master socket no longer needs to worry about confirms */
+ opt->dccpop_sc = NULL; /* it's not a memleak---new socket has it */
+
+ /* reset state for a new socket */
+ opt->dccpop_conf = 0;
}
- return 0;
-fast_path_unknown:
- if (!mandatory)
- return dccp_push_empty_confirm(fn, feat, local);
+ /* XXX not doing anything about the conf queue */
+
+out:
+ return rc;
-fast_path_failed:
- return mandatory ? DCCP_RESET_CODE_MANDATORY_ERROR
- : DCCP_RESET_CODE_OPTION_ERROR;
+out_clean:
+ dccp_feat_clean(newdmsk);
+ rc = -ENOMEM;
+ goto out;
}
-/**
- * dccp_feat_parse_options - Process Feature-Negotiation Options
- * @sk: for general use and used by the client during connection setup
- * @dreq: used by the server during connection setup
- * @mandatory: whether @opt was preceded by a Mandatory option
- * @opt: %DCCPO_CHANGE_L | %DCCPO_CHANGE_R | %DCCPO_CONFIRM_L | %DCCPO_CONFIRM_R
- * @feat: one of %dccp_feature_numbers
- * @val: value contents of @opt
- * @len: length of @val in bytes
- * Returns 0 on success, a Reset code for ending the connection otherwise.
- */
-int dccp_feat_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
- u8 mandatory, u8 opt, u8 feat, u8 *val, u8 len)
+EXPORT_SYMBOL_GPL(dccp_feat_clone);
+
+static int __dccp_feat_init(struct dccp_minisock *dmsk, u8 type, u8 feat,
+ u8 *val, u8 len)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct list_head *fn = dreq ? &dreq->dreq_featneg : &dp->dccps_featneg;
- bool server = false;
+ int rc = -ENOMEM;
+ u8 *copy = kmemdup(val, len, GFP_KERNEL);
- switch (sk->sk_state) {
- /*
- * Negotiation during connection setup
- */
- case DCCP_LISTEN:
- server = true; /* fall through */
- case DCCP_REQUESTING:
- switch (opt) {
- case DCCPO_CHANGE_L:
- case DCCPO_CHANGE_R:
- return dccp_feat_change_recv(fn, mandatory, opt, feat,
- val, len, server);
- case DCCPO_CONFIRM_R:
- case DCCPO_CONFIRM_L:
- return dccp_feat_confirm_recv(fn, mandatory, opt, feat,
- val, len, server);
- }
- break;
- /*
- * Support for exchanging NN options on an established connection
- * This is currently restricted to Ack Ratio (RFC 4341, 6.1.2)
- */
- case DCCP_OPEN:
- case DCCP_PARTOPEN:
- return dccp_feat_handle_nn_established(sk, mandatory, opt, feat,
- val, len);
+ if (copy != NULL) {
+ rc = dccp_feat_change(dmsk, type, feat, copy, len, GFP_KERNEL);
+ if (rc)
+ kfree(copy);
}
- return 0; /* ignore FN options in all other states */
+ return rc;
}
-/**
- * dccp_feat_init - Seed feature negotiation with host-specific defaults
- * This initialises global defaults, depending on the value of the sysctls.
- * These can later be overridden by registering changes via setsockopt calls.
- * The last link in the chain is finalise_settings, to make sure that between
- * here and the start of actual feature negotiation no inconsistencies enter.
- *
- * All features not appearing below use either defaults or are otherwise
- * later adjusted through dccp_feat_finalise_settings().
- */
-int dccp_feat_init(struct sock *sk)
+int dccp_feat_init(struct dccp_minisock *dmsk)
{
- struct list_head *fn = &dccp_sk(sk)->dccps_featneg;
- u8 on = 1, off = 0;
int rc;
- struct {
- u8 *val;
- u8 len;
- } tx, rx;
-
- /* Non-negotiable (NN) features */
- rc = __feat_register_nn(fn, DCCPF_SEQUENCE_WINDOW, 0,
- sysctl_dccp_sequence_window);
- if (rc)
- return rc;
- /* Server-priority (SP) features */
-
- /* Advertise that short seqnos are not supported (7.6.1) */
- rc = __feat_register_sp(fn, DCCPF_SHORT_SEQNOS, true, true, &off, 1);
- if (rc)
- return rc;
+ INIT_LIST_HEAD(&dmsk->dccpms_pending);
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
- /* RFC 4340 12.1: "If a DCCP is not ECN capable, ..." */
- rc = __feat_register_sp(fn, DCCPF_ECN_INCAPABLE, true, true, &on, 1);
+ /* CCID L */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_CCID,
+ &dmsk->dccpms_tx_ccid, 1);
if (rc)
- return rc;
-
- /*
- * We advertise the available list of CCIDs and reorder according to
- * preferences, to avoid failure resulting from negotiating different
- * singleton values (which always leads to failure).
- * These settings can still (later) be overridden via sockopts.
- */
- if (ccid_get_builtin_ccids(&tx.val, &tx.len) ||
- ccid_get_builtin_ccids(&rx.val, &rx.len))
- return -ENOBUFS;
-
- /* Pre-load all CCID modules that are going to be advertised */
- rc = -EUNATCH;
- if (ccid_request_modules(tx.val, tx.len))
- goto free_ccid_lists;
-
- if (!dccp_feat_prefer(sysctl_dccp_tx_ccid, tx.val, tx.len) ||
- !dccp_feat_prefer(sysctl_dccp_rx_ccid, rx.val, rx.len))
- goto free_ccid_lists;
+ goto out;
- rc = __feat_register_sp(fn, DCCPF_CCID, true, false, tx.val, tx.len);
+ /* CCID R */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_R, DCCPF_CCID,
+ &dmsk->dccpms_rx_ccid, 1);
if (rc)
- goto free_ccid_lists;
+ goto out;
- rc = __feat_register_sp(fn, DCCPF_CCID, false, false, rx.val, rx.len);
-
-free_ccid_lists:
- kfree(tx.val);
- kfree(rx.val);
+ /* Ack ratio */
+ rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
+ &dmsk->dccpms_ack_ratio, 1);
+out:
return rc;
}
-int dccp_feat_activate_values(struct sock *sk, struct list_head *fn_list)
-{
- struct dccp_sock *dp = dccp_sk(sk);
- struct dccp_feat_entry *cur, *next;
- int idx;
- dccp_feat_val *fvals[DCCP_FEAT_SUPPORTED_MAX][2] = {
- [0 ... DCCP_FEAT_SUPPORTED_MAX-1] = { NULL, NULL }
- };
-
- list_for_each_entry(cur, fn_list, node) {
- /*
- * An empty Confirm means that either an unknown feature type
- * or an invalid value was present. In the first case there is
- * nothing to activate, in the other the default value is used.
- */
- if (cur->empty_confirm)
- continue;
+EXPORT_SYMBOL_GPL(dccp_feat_init);
- idx = dccp_feat_index(cur->feat_num);
- if (idx < 0) {
- DCCP_BUG("Unknown feature %u", cur->feat_num);
- goto activation_failed;
- }
- if (cur->state != FEAT_STABLE) {
- DCCP_CRIT("Negotiation of %s %s failed in state %s",
- cur->is_local ? "local" : "remote",
- dccp_feat_fname(cur->feat_num),
- dccp_feat_sname[cur->state]);
- goto activation_failed;
- }
- fvals[idx][cur->is_local] = &cur->val;
+#ifdef CONFIG_IP_DCCP_DEBUG
+const char *dccp_feat_typename(const u8 type)
+{
+ switch(type) {
+ case DCCPO_CHANGE_L: return("ChangeL");
+ case DCCPO_CONFIRM_L: return("ConfirmL");
+ case DCCPO_CHANGE_R: return("ChangeR");
+ case DCCPO_CONFIRM_R: return("ConfirmR");
+ /* the following case must not appear in feature negotation */
+ default: dccp_pr_debug("unknown type %d [BUG!]\n", type);
}
+ return NULL;
+}
- /*
- * Activate in decreasing order of index, so that the CCIDs are always
- * activated as the last feature. This avoids the case where a CCID
- * relies on the initialisation of one or more features that it depends
- * on (e.g. Send NDP Count, Send Ack Vector, and Ack Ratio features).
- */
- for (idx = DCCP_FEAT_SUPPORTED_MAX; --idx >= 0;)
- if (__dccp_feat_activate(sk, idx, 0, fvals[idx][0]) ||
- __dccp_feat_activate(sk, idx, 1, fvals[idx][1])) {
- DCCP_CRIT("Could not activate %d", idx);
- goto activation_failed;
- }
+EXPORT_SYMBOL_GPL(dccp_feat_typename);
- /* Clean up Change options which have been confirmed already */
- list_for_each_entry_safe(cur, next, fn_list, node)
- if (!cur->needs_confirm)
- dccp_feat_list_pop(cur);
+const char *dccp_feat_name(const u8 feat)
+{
+ static const char *feature_names[] = {
+ [DCCPF_RESERVED] = "Reserved",
+ [DCCPF_CCID] = "CCID",
+ [DCCPF_SHORT_SEQNOS] = "Allow Short Seqnos",
+ [DCCPF_SEQUENCE_WINDOW] = "Sequence Window",
+ [DCCPF_ECN_INCAPABLE] = "ECN Incapable",
+ [DCCPF_ACK_RATIO] = "Ack Ratio",
+ [DCCPF_SEND_ACK_VECTOR] = "Send ACK Vector",
+ [DCCPF_SEND_NDP_COUNT] = "Send NDP Count",
+ [DCCPF_MIN_CSUM_COVER] = "Min. Csum Coverage",
+ [DCCPF_DATA_CHECKSUM] = "Send Data Checksum",
+ };
+ if (feat > DCCPF_DATA_CHECKSUM && feat < DCCPF_MIN_CCID_SPECIFIC)
+ return feature_names[DCCPF_RESERVED];
- dccp_pr_debug("Activation OK\n");
- return 0;
+ if (feat >= DCCPF_MIN_CCID_SPECIFIC)
+ return "CCID-specific";
-activation_failed:
- /*
- * We clean up everything that may have been allocated, since
- * it is difficult to track at which stage negotiation failed.
- * This is ok, since all allocation functions below are robust
- * against NULL arguments.
- */
- ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
- ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
- dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
- return -1;
+ return feature_names[feat];
}
+
+EXPORT_SYMBOL_GPL(dccp_feat_name);
+#endif /* CONFIG_IP_DCCP_DEBUG */
/*
* net/dccp/feat.h
*
- * Feature negotiation for the DCCP protocol (RFC 4340, section 6)
- * Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
+ * An implementation of the DCCP protocol
* Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
*/
+
#include <linux/types.h>
#include "dccp.h"
-/*
- * Known limit values
- */
-/* Ack Ratio takes 2-byte integer values (11.3) */
-#define DCCPF_ACK_RATIO_MAX 0xFFFF
-/* Wmin=32 and Wmax=2^46-1 from 7.5.2 */
-#define DCCPF_SEQ_WMIN 32
-#define DCCPF_SEQ_WMAX 0x3FFFFFFFFFFFull
-/* Maximum number of SP values that fit in a single (Confirm) option */
-#define DCCP_FEAT_MAX_SP_VALS (DCCP_SINGLE_OPT_MAXLEN - 2)
-
-enum dccp_feat_type {
- FEAT_AT_RX = 1, /* located at RX side of half-connection */
- FEAT_AT_TX = 2, /* located at TX side of half-connection */
- FEAT_SP = 4, /* server-priority reconciliation (6.3.1) */
- FEAT_NN = 8, /* non-negotiable reconciliation (6.3.2) */
- FEAT_UNKNOWN = 0xFF /* not understood or invalid feature */
-};
-
-enum dccp_feat_state {
- FEAT_DEFAULT = 0, /* using default values from 6.4 */
- FEAT_INITIALISING, /* feature is being initialised */
- FEAT_CHANGING, /* Change sent but not confirmed yet */
- FEAT_UNSTABLE, /* local modification in state CHANGING */
- FEAT_STABLE /* both ends (think they) agree */
-};
+#ifdef CONFIG_IP_DCCP_DEBUG
+extern const char *dccp_feat_typename(const u8 type);
+extern const char *dccp_feat_name(const u8 feat);
-/**
- * dccp_feat_val - Container for SP or NN feature values
- * @nn: single NN value
- * @sp.vec: single SP value plus optional preference list
- * @sp.len: length of @sp.vec in bytes
- */
-typedef union {
- u64 nn;
- struct {
- u8 *vec;
- u8 len;
- } sp;
-} dccp_feat_val;
-
-/**
- * struct feat_entry - Data structure to perform feature negotiation
- * @feat_num: one of %dccp_feature_numbers
- * @val: feature's current value (SP features may have preference list)
- * @state: feature's current state
- * @needs_mandatory: whether Mandatory options should be sent
- * @needs_confirm: whether to send a Confirm instead of a Change
- * @empty_confirm: whether to send an empty Confirm (depends on @needs_confirm)
- * @is_local: feature location (1) or feature-remote (0)
- * @node: list pointers, entries arranged in FIFO order
- */
-struct dccp_feat_entry {
- u8 feat_num;
- dccp_feat_val val;
- enum dccp_feat_state state:8;
- bool needs_mandatory:1,
- needs_confirm:1,
- empty_confirm:1,
- is_local:1;
-
- struct list_head node;
-};
-
-static inline u8 dccp_feat_genopt(struct dccp_feat_entry *entry)
+static inline void dccp_feat_debug(const u8 type, const u8 feat, const u8 val)
{
- if (entry->needs_confirm)
- return entry->is_local ? DCCPO_CONFIRM_L : DCCPO_CONFIRM_R;
- return entry->is_local ? DCCPO_CHANGE_L : DCCPO_CHANGE_R;
+ dccp_pr_debug("%s(%s (%d), %d)\n", dccp_feat_typename(type),
+ dccp_feat_name(feat), feat, val);
}
+#else
+#define dccp_feat_debug(type, feat, val)
+#endif /* CONFIG_IP_DCCP_DEBUG */
+
+extern int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
+ u8 *val, u8 len, gfp_t gfp);
+extern int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len);
+extern int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len);
+extern void dccp_feat_clean(struct dccp_minisock *dmsk);
+extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
+extern int dccp_feat_init(struct dccp_minisock *dmsk);
-/**
- * struct ccid_dependency - Track changes resulting from choosing a CCID
- * @dependent_feat: one of %dccp_feature_numbers
- * @is_local: local (1) or remote (0) @dependent_feat
- * @is_mandatory: whether presence of @dependent_feat is mission-critical or not
- * @val: corresponding default value for @dependent_feat (u8 is sufficient here)
- */
-struct ccid_dependency {
- u8 dependent_feat;
- bool is_local:1,
- is_mandatory:1;
- u8 val;
-};
-
-/*
- * Sysctls to seed defaults for feature negotiation
- */
-extern unsigned long sysctl_dccp_sequence_window;
-extern int sysctl_dccp_rx_ccid;
-extern int sysctl_dccp_tx_ccid;
-
-extern int dccp_feat_init(struct sock *sk);
-extern void dccp_feat_initialise_sysctls(void);
-extern int dccp_feat_register_sp(struct sock *sk, u8 feat, u8 is_local,
- u8 const *list, u8 len);
-extern int dccp_feat_register_nn(struct sock *sk, u8 feat, u64 val);
-extern int dccp_feat_parse_options(struct sock *, struct dccp_request_sock *,
- u8 mand, u8 opt, u8 feat, u8 *val, u8 len);
-extern int dccp_feat_clone_list(struct list_head const *, struct list_head *);
-
-/*
- * Encoding variable-length options and their maximum length.
- *
- * This affects NN options (SP options are all u8) and other variable-length
- * options (see table 3 in RFC 4340). The limit is currently given the Sequence
- * Window NN value (sec. 7.5.2) and the NDP count (sec. 7.7) option, all other
- * options consume less than 6 bytes (timestamps are 4 bytes).
- * When updating this constant (e.g. due to new internet drafts / RFCs), make
- * sure that you also update all code which refers to it.
- */
-#define DCCP_OPTVAL_MAXLEN 6
-
-extern void dccp_encode_value_var(const u64 value, u8 *to, const u8 len);
-extern u64 dccp_decode_value_var(const u8 *bf, const u8 len);
-
-extern int dccp_insert_option_mandatory(struct sk_buff *skb);
-extern int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat,
- u8 *val, u8 len, bool repeat_first);
#endif /* _DCCP_FEAT_H */
dccp_time_wait(sk, DCCP_TIME_WAIT, 0);
}
-static void dccp_handle_ackvec_processing(struct sock *sk, struct sk_buff *skb)
+static void dccp_event_ack_recv(struct sock *sk, struct sk_buff *skb)
{
- struct dccp_ackvec *av = dccp_sk(sk)->dccps_hc_rx_ackvec;
+ struct dccp_sock *dp = dccp_sk(sk);
- if (av == NULL)
- return;
- if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
- dccp_ackvec_clear_state(av, DCCP_SKB_CB(skb)->dccpd_ack_seq);
- dccp_ackvec_input(av, skb);
+ if (dccp_msk(sk)->dccpms_send_ack_vector)
+ dccp_ackvec_check_rcv_ackno(dp->dccps_hc_rx_ackvec, sk,
+ DCCP_SKB_CB(skb)->dccpd_ack_seq);
}
static void dccp_deliver_input_to_ccids(struct sock *sk, struct sk_buff *skb)
int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
const struct dccp_hdr *dh, const unsigned len)
{
+ struct dccp_sock *dp = dccp_sk(sk);
+
if (dccp_check_seqno(sk, skb))
goto discard;
if (dccp_parse_options(sk, NULL, skb))
return 1;
- dccp_handle_ackvec_processing(sk, skb);
+ if (DCCP_SKB_CB(skb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+ dccp_event_ack_recv(sk, skb);
+
+ if (dccp_msk(sk)->dccpms_send_ack_vector &&
+ dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
+ DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_ACKVEC_STATE_RECEIVED))
+ goto discard;
dccp_deliver_input_to_ccids(sk, skb);
return __dccp_rcv_established(sk, skb, dh, len);
goto out_invalid_packet;
}
- /*
- * If option processing (Step 8) failed, return 1 here so that
- * dccp_v4_do_rcv() sends a Reset. The Reset code depends on
- * the option type and is set in dccp_parse_options().
- */
if (dccp_parse_options(sk, NULL, skb))
- return 1;
+ goto out_invalid_packet;
/* Obtain usec RTT sample from SYN exchange (used by CCID 3) */
if (likely(dp->dccps_options_received.dccpor_timestamp_echo))
dp->dccps_syn_rtt = dccp_sample_rtt(sk, 10 * (tstamp -
dp->dccps_options_received.dccpor_timestamp_echo));
+ if (dccp_msk(sk)->dccpms_send_ack_vector &&
+ dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
+ DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_ACKVEC_STATE_RECEIVED))
+ goto out_invalid_packet; /* FIXME: change error code */
+
/* Stop the REQUEST timer */
inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
WARN_ON(sk->sk_send_head == NULL);
kfree_skb(sk->sk_send_head);
sk->sk_send_head = NULL;
+ dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq;
+ dccp_update_gsr(sk, dp->dccps_isr);
/*
- * Set ISR, GSR from packet. ISS was set in dccp_v{4,6}_connect
- * and GSS in dccp_transmit_skb(). Setting AWL/AWH and SWL/SWH
- * is done as part of activating the feature values below, since
- * these settings depend on the local/remote Sequence Window
- * features, which were undefined or not confirmed until now.
+ * SWL and AWL are initially adjusted so that they are not less than
+ * the initial Sequence Numbers received and sent, respectively:
+ * SWL := max(GSR + 1 - floor(W/4), ISR),
+ * AWL := max(GSS - W' + 1, ISS).
+ * These adjustments MUST be applied only at the beginning of the
+ * connection.
+ *
+ * AWL was adjusted in dccp_v4_connect -acme
*/
- dp->dccps_gsr = dp->dccps_isr = DCCP_SKB_CB(skb)->dccpd_seq;
+ dccp_set_seqno(&dp->dccps_swl,
+ max48(dp->dccps_swl, dp->dccps_isr));
dccp_sync_mss(sk, icsk->icsk_pmtu_cookie);
*/
dccp_set_state(sk, DCCP_PARTOPEN);
- /*
- * If feature negotiation was successful, activate features now;
- * an activation failure means that this host could not activate
- * one ore more features (e.g. insufficient memory), which would
- * leave at least one feature in an undefined state.
- */
- if (dccp_feat_activate_values(sk, &dp->dccps_featneg))
- goto unable_to_proceed;
-
/* Make sure socket is routed, for correct metrics. */
icsk->icsk_af_ops->rebuild_header(sk);
/* dccp_v4_do_rcv will send a reset */
DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_PACKET_ERROR;
return 1;
-
-unable_to_proceed:
- DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_ABORTED;
- /*
- * We mark this socket as no longer usable, so that the loop in
- * dccp_sendmsg() terminates and the application gets notified.
- */
- dccp_set_state(sk, DCCP_CLOSED);
- sk->sk_err = ECOMM;
- return 1;
}
static int dccp_rcv_respond_partopen_state_process(struct sock *sk,
if (inet_csk(sk)->icsk_af_ops->conn_request(sk,
skb) < 0)
return 1;
+
+ /* FIXME: do congestion control initialization */
goto discard;
}
if (dh->dccph_type == DCCP_PKT_RESET)
/* Caller (dccp_v4_do_rcv) will send Reset */
dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
return 1;
- } else if (sk->sk_state == DCCP_CLOSED) {
- dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
- return 1;
}
- /* Step 6: Check sequence numbers (omitted in LISTEN/REQUEST state) */
- if (sk->sk_state != DCCP_REQUESTING && dccp_check_seqno(sk, skb))
- goto discard;
+ if (sk->sk_state != DCCP_REQUESTING) {
+ if (dccp_check_seqno(sk, skb))
+ goto discard;
- /*
- * Step 7: Check for unexpected packet types
- * If (S.is_server and P.type == Response)
- * or (S.is_client and P.type == Request)
- * or (S.state == RESPOND and P.type == Data),
- * Send Sync packet acknowledging P.seqno
- * Drop packet and return
- */
- if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
- dh->dccph_type == DCCP_PKT_RESPONSE) ||
- (dp->dccps_role == DCCP_ROLE_CLIENT &&
- dh->dccph_type == DCCP_PKT_REQUEST) ||
- (sk->sk_state == DCCP_RESPOND && dh->dccph_type == DCCP_PKT_DATA)) {
- dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC);
- goto discard;
- }
+ /*
+ * Step 8: Process options and mark acknowledgeable
+ */
+ if (dccp_parse_options(sk, NULL, skb))
+ return 1;
- /* Step 8: Process options */
- if (dccp_parse_options(sk, NULL, skb))
- return 1;
+ if (dcb->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
+ dccp_event_ack_recv(sk, skb);
+
+ if (dccp_msk(sk)->dccpms_send_ack_vector &&
+ dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
+ DCCP_SKB_CB(skb)->dccpd_seq,
+ DCCP_ACKVEC_STATE_RECEIVED))
+ goto discard;
+
+ dccp_deliver_input_to_ccids(sk, skb);
+ }
/*
* Step 9: Process Reset
* S.state := TIMEWAIT
* Set TIMEWAIT timer
* Drop packet and return
- */
+ */
if (dh->dccph_type == DCCP_PKT_RESET) {
dccp_rcv_reset(sk, skb);
return 0;
- } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) { /* Step 13 */
+ /*
+ * Step 7: Check for unexpected packet types
+ * If (S.is_server and P.type == Response)
+ * or (S.is_client and P.type == Request)
+ * or (S.state == RESPOND and P.type == Data),
+ * Send Sync packet acknowledging P.seqno
+ * Drop packet and return
+ */
+ } else if ((dp->dccps_role != DCCP_ROLE_CLIENT &&
+ dh->dccph_type == DCCP_PKT_RESPONSE) ||
+ (dp->dccps_role == DCCP_ROLE_CLIENT &&
+ dh->dccph_type == DCCP_PKT_REQUEST) ||
+ (sk->sk_state == DCCP_RESPOND &&
+ dh->dccph_type == DCCP_PKT_DATA)) {
+ dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNC);
+ goto discard;
+ } else if (dh->dccph_type == DCCP_PKT_CLOSEREQ) {
if (dccp_rcv_closereq(sk, skb))
return 0;
goto discard;
- } else if (dh->dccph_type == DCCP_PKT_CLOSE) { /* Step 14 */
+ } else if (dh->dccph_type == DCCP_PKT_CLOSE) {
if (dccp_rcv_close(sk, skb))
return 0;
goto discard;
}
switch (sk->sk_state) {
+ case DCCP_CLOSED:
+ dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
+ return 1;
+
case DCCP_REQUESTING:
+ /* FIXME: do congestion control initialization */
+
queued = dccp_rcv_request_sent_state_process(sk, skb, dh, len);
if (queued >= 0)
return queued;
__kfree_skb(skb);
return 0;
- case DCCP_PARTOPEN:
- /* Step 8: if using Ack Vectors, mark packet acknowledgeable */
- dccp_handle_ackvec_processing(sk, skb);
- dccp_deliver_input_to_ccids(sk, skb);
- /* fall through */
case DCCP_RESPOND:
+ case DCCP_PARTOPEN:
queued = dccp_rcv_respond_partopen_state_process(sk, skb,
dh, len);
break;
/* dccpor_elapsed_time is either zeroed out or set and > 0 */
delta -= dccp_sk(sk)->dccps_options_received.dccpor_elapsed_time * 10;
- return dccp_sane_rtt(delta);
+ if (unlikely(delta <= 0)) {
+ DCCP_WARN("unusable RTT sample %ld, using min\n", delta);
+ return DCCP_SANE_RTT_MIN;
+ }
+ if (unlikely(delta > DCCP_SANE_RTT_MAX)) {
+ DCCP_WARN("RTT sample %ld too large, using max\n", delta);
+ return DCCP_SANE_RTT_MAX;
+ }
+
+ return delta;
}
EXPORT_SYMBOL_GPL(dccp_sample_rtt);
static void dccp_v4_reqsk_destructor(struct request_sock *req)
{
- dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
kfree(inet_rsk(req)->opt);
}
if (req == NULL)
goto drop;
- if (dccp_reqsk_init(req, dccp_sk(sk), skb))
- goto drop_and_free;
+ dccp_reqsk_init(req, skb);
dreq = dccp_rsk(req);
if (dccp_parse_options(sk, dreq, skb))
static void dccp_v6_reqsk_destructor(struct request_sock *req)
{
- dccp_feat_list_purge(&dccp_rsk(req)->dreq_featneg);
if (inet6_rsk(req)->pktopts != NULL)
kfree_skb(inet6_rsk(req)->pktopts);
}
if (req == NULL)
goto drop;
- if (dccp_reqsk_init(req, dccp_sk(sk), skb))
- goto drop_and_free;
+ dccp_reqsk_init(req, skb);
dreq = dccp_rsk(req);
if (dccp_parse_options(sk, dreq, skb))
EXPORT_SYMBOL_GPL(dccp_death_row);
+void dccp_minisock_init(struct dccp_minisock *dmsk)
+{
+ dmsk->dccpms_sequence_window = sysctl_dccp_feat_sequence_window;
+ dmsk->dccpms_rx_ccid = sysctl_dccp_feat_rx_ccid;
+ dmsk->dccpms_tx_ccid = sysctl_dccp_feat_tx_ccid;
+ dmsk->dccpms_ack_ratio = sysctl_dccp_feat_ack_ratio;
+ dmsk->dccpms_send_ack_vector = sysctl_dccp_feat_send_ack_vector;
+ dmsk->dccpms_send_ndp_count = sysctl_dccp_feat_send_ndp_count;
+}
+
void dccp_time_wait(struct sock *sk, int state, int timeo)
{
struct inet_timewait_sock *tw = NULL;
struct sock *newsk = inet_csk_clone(sk, req, GFP_ATOMIC);
if (newsk != NULL) {
- struct dccp_request_sock *dreq = dccp_rsk(req);
+ const struct dccp_request_sock *dreq = dccp_rsk(req);
struct inet_connection_sock *newicsk = inet_csk(newsk);
struct dccp_sock *newdp = dccp_sk(newsk);
+ struct dccp_minisock *newdmsk = dccp_msk(newsk);
newdp->dccps_role = DCCP_ROLE_SERVER;
newdp->dccps_hc_rx_ackvec = NULL;
newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
- INIT_LIST_HEAD(&newdp->dccps_featneg);
+ if (dccp_feat_clone(sk, newsk))
+ goto out_free;
+
+ if (newdmsk->dccpms_send_ack_vector) {
+ newdp->dccps_hc_rx_ackvec =
+ dccp_ackvec_alloc(GFP_ATOMIC);
+ if (unlikely(newdp->dccps_hc_rx_ackvec == NULL))
+ goto out_free;
+ }
+
+ newdp->dccps_hc_rx_ccid =
+ ccid_hc_rx_new(newdmsk->dccpms_rx_ccid,
+ newsk, GFP_ATOMIC);
+ newdp->dccps_hc_tx_ccid =
+ ccid_hc_tx_new(newdmsk->dccpms_tx_ccid,
+ newsk, GFP_ATOMIC);
+ if (unlikely(newdp->dccps_hc_rx_ccid == NULL ||
+ newdp->dccps_hc_tx_ccid == NULL)) {
+ dccp_ackvec_free(newdp->dccps_hc_rx_ackvec);
+ ccid_hc_rx_delete(newdp->dccps_hc_rx_ccid, newsk);
+ ccid_hc_tx_delete(newdp->dccps_hc_tx_ccid, newsk);
+out_free:
+ /* It is still raw copy of parent, so invalidate
+ * destructor and make plain sk_free() */
+ newsk->sk_destruct = NULL;
+ sk_free(newsk);
+ return NULL;
+ }
+
/*
* Step 3: Process LISTEN state
*
* Choose S.ISS (initial seqno) or set from Init Cookies
* Initialize S.GAR := S.ISS
- * Set S.ISR, S.GSR from packet (or Init Cookies)
- *
- * Setting AWL/AWH and SWL/SWH happens as part of the feature
- * activation below, as these windows all depend on the local
- * and remote Sequence Window feature values (7.5.2).
+ * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
*/
- newdp->dccps_gss = newdp->dccps_iss = dreq->dreq_iss;
- newdp->dccps_gar = newdp->dccps_iss;
- newdp->dccps_gsr = newdp->dccps_isr = dreq->dreq_isr;
+
+ /* See dccp_v4_conn_request */
+ newdmsk->dccpms_sequence_window = req->rcv_wnd;
+
+ newdp->dccps_gar = newdp->dccps_iss = dreq->dreq_iss;
+ dccp_update_gss(newsk, dreq->dreq_iss);
+
+ newdp->dccps_isr = dreq->dreq_isr;
+ dccp_update_gsr(newsk, dreq->dreq_isr);
/*
- * Activate features: initialise CCIDs, sequence windows etc.
+ * SWL and AWL are initially adjusted so that they are not less than
+ * the initial Sequence Numbers received and sent, respectively:
+ * SWL := max(GSR + 1 - floor(W/4), ISR),
+ * AWL := max(GSS - W' + 1, ISS).
+ * These adjustments MUST be applied only at the beginning of the
+ * connection.
*/
- if (dccp_feat_activate_values(newsk, &dreq->dreq_featneg)) {
- /* It is still raw copy of parent, so invalidate
- * destructor and make plain sk_free() */
- newsk->sk_destruct = NULL;
- sk_free(newsk);
- return NULL;
- }
+ dccp_set_seqno(&newdp->dccps_swl,
+ max48(newdp->dccps_swl, newdp->dccps_isr));
+ dccp_set_seqno(&newdp->dccps_awl,
+ max48(newdp->dccps_awl, newdp->dccps_iss));
+
dccp_init_xmit_timers(newsk);
DCCP_INC_STATS_BH(DCCP_MIB_PASSIVEOPENS);
EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
-int dccp_reqsk_init(struct request_sock *req,
- struct dccp_sock const *dp, struct sk_buff const *skb)
+void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb)
{
struct dccp_request_sock *dreq = dccp_rsk(req);
inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
inet_rsk(req)->acked = 0;
+ req->rcv_wnd = sysctl_dccp_feat_sequence_window;
dreq->dreq_timestamp_echo = 0;
-
- /* inherit feature negotiation options from listening socket */
- return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
}
EXPORT_SYMBOL_GPL(dccp_reqsk_init);
#include "dccp.h"
#include "feat.h"
-u64 dccp_decode_value_var(const u8 *bf, const u8 len)
+int sysctl_dccp_feat_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW;
+int sysctl_dccp_feat_rx_ccid = DCCPF_INITIAL_CCID;
+int sysctl_dccp_feat_tx_ccid = DCCPF_INITIAL_CCID;
+int sysctl_dccp_feat_ack_ratio = DCCPF_INITIAL_ACK_RATIO;
+int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR;
+int sysctl_dccp_feat_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT;
+
+static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
{
- u64 value = 0;
+ u32 value = 0;
- if (len >= DCCP_OPTVAL_MAXLEN)
- value += ((u64)*bf++) << 40;
- if (len > 4)
- value += ((u64)*bf++) << 32;
if (len > 3)
- value += ((u64)*bf++) << 24;
+ value += *bf++ << 24;
if (len > 2)
- value += ((u64)*bf++) << 16;
+ value += *bf++ << 16;
if (len > 1)
- value += ((u64)*bf++) << 8;
+ value += *bf++ << 8;
if (len > 0)
value += *bf;
struct dccp_sock *dp = dccp_sk(sk);
const struct dccp_hdr *dh = dccp_hdr(skb);
const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
+ u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
unsigned char *opt_ptr = options;
const unsigned char *opt_end = (unsigned char *)dh +
}
/*
+ * CCID-Specific Options (from RFC 4340, sec. 10.3):
+ *
+ * Option numbers 128 through 191 are for options sent from the
+ * HC-Sender to the HC-Receiver; option numbers 192 through 255
+ * are for options sent from the HC-Receiver to the HC-Sender.
+ *
* CCID-specific options are ignored during connection setup, as
* negotiation may still be in progress (see RFC 4340, 10.3).
* The same applies to Ack Vectors, as these depend on the CCID.
+ *
*/
- if (dreq != NULL && (opt >= DCCPO_MIN_RX_CCID_SPECIFIC ||
+ if (dreq != NULL && (opt >= 128 ||
opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1))
goto ignore_option;
dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
(unsigned long long)opt_recv->dccpor_ndp);
break;
- case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R:
- if (pkt_type == DCCP_PKT_DATA) /* RFC 4340, 6 */
+ case DCCPO_CHANGE_L:
+ /* fall through */
+ case DCCPO_CHANGE_R:
+ if (pkt_type == DCCP_PKT_DATA)
break;
- rc = dccp_feat_parse_options(sk, dreq, mandatory, opt,
- *value, value + 1, len - 1);
- if (rc)
- goto out_featneg_failed;
+ if (len < 2)
+ goto out_invalid_option;
+ rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
+ len - 1);
+ /*
+ * When there is a change error, change_recv is
+ * responsible for dealing with it. i.e. reply with an
+ * empty confirm.
+ * If the change was mandatory, then we need to die.
+ */
+ if (rc && mandatory)
+ goto out_invalid_option;
+ break;
+ case DCCPO_CONFIRM_L:
+ /* fall through */
+ case DCCPO_CONFIRM_R:
+ if (pkt_type == DCCP_PKT_DATA)
+ break;
+ if (len < 2) /* FIXME this disallows empty confirm */
+ goto out_invalid_option;
+ if (dccp_feat_confirm_recv(sk, opt, *value,
+ value + 1, len - 1))
+ goto out_invalid_option;
+ break;
+ case DCCPO_ACK_VECTOR_0:
+ case DCCPO_ACK_VECTOR_1:
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
+ break;
+
+ if (dccp_msk(sk)->dccpms_send_ack_vector &&
+ dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
+ goto out_invalid_option;
break;
case DCCPO_TIMESTAMP:
if (len != 4)
dccp_role(sk), ntohl(opt_val),
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
- /* schedule an Ack in case this sender is quiescent */
- inet_csk_schedule_ack(sk);
break;
case DCCPO_TIMESTAMP_ECHO:
if (len != 4 && len != 6 && len != 8)
dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
dccp_role(sk), elapsed_time);
break;
- case DCCPO_MIN_RX_CCID_SPECIFIC ... DCCPO_MAX_RX_CCID_SPECIFIC:
+ case 128 ... 191: {
+ const u16 idx = value - options;
+
if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
- pkt_type, opt, value, len))
+ opt, len, idx,
+ value) != 0)
goto out_invalid_option;
+ }
break;
- case DCCPO_ACK_VECTOR_0:
- case DCCPO_ACK_VECTOR_1:
- if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
- break;
- /*
- * Ack vectors are processed by the TX CCID if it is
- * interested. The RX CCID need not parse Ack Vectors,
- * since it is only interested in clearing old state.
- * Fall through.
- */
- case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC:
+ case 192 ... 255: {
+ const u16 idx = value - options;
+
if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
- pkt_type, opt, value, len))
+ opt, len, idx,
+ value) != 0)
goto out_invalid_option;
+ }
break;
default:
DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
out_invalid_option:
DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
- rc = DCCP_RESET_CODE_OPTION_ERROR;
-out_featneg_failed:
- DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc);
- DCCP_SKB_CB(skb)->dccpd_reset_code = rc;
+ DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
+ DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len);
DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt;
DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0;
DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0;
EXPORT_SYMBOL_GPL(dccp_parse_options);
-void dccp_encode_value_var(const u64 value, u8 *to, const u8 len)
+static void dccp_encode_value_var(const u32 value, unsigned char *to,
+ const unsigned int len)
{
- if (len >= DCCP_OPTVAL_MAXLEN)
- *to++ = (value & 0xFF0000000000ull) >> 40;
- if (len > 4)
- *to++ = (value & 0xFF00000000ull) >> 32;
if (len > 3)
*to++ = (value & 0xFF000000) >> 24;
if (len > 2)
return 0;
}
-static int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb)
+static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
+ u8 *val, u8 len)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct dccp_ackvec *av = dp->dccps_hc_rx_ackvec;
- struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
- const u16 buflen = dccp_ackvec_buflen(av);
- /* Figure out how many options do we need to represent the ackvec */
- const u8 nr_opts = DIV_ROUND_UP(buflen, DCCP_SINGLE_OPT_MAXLEN);
- u16 len = buflen + 2 * nr_opts;
- u8 i, nonce = 0;
- const unsigned char *tail, *from;
- unsigned char *to;
+ u8 *to;
- if (dcb->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
- DCCP_WARN("Lacking space for %u bytes on %s packet\n", len,
- dccp_packet_name(dcb->dccpd_type));
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
+ DCCP_WARN("packet too small for feature %d option!\n", feat);
return -1;
}
- /*
- * Since Ack Vectors are variable-length, we can not always predict
- * their size. To catch exception cases where the space is running out
- * on the skb, a separate Sync is scheduled to carry the Ack Vector.
- */
- if (len > DCCPAV_MIN_OPTLEN &&
- len + dcb->dccpd_opt_len + skb->len > dp->dccps_mss_cache) {
- DCCP_WARN("No space left for Ack Vector (%u) on skb (%u+%u), "
- "MPS=%u ==> reduce payload size?\n", len, skb->len,
- dcb->dccpd_opt_len, dp->dccps_mss_cache);
- dp->dccps_sync_scheduled = 1;
- return 0;
- }
- dcb->dccpd_opt_len += len;
- to = skb_push(skb, len);
- len = buflen;
- from = av->av_buf + av->av_buf_head;
- tail = av->av_buf + DCCPAV_MAX_ACKVEC_LEN;
+ DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
- for (i = 0; i < nr_opts; ++i) {
- int copylen = len;
-
- if (len > DCCP_SINGLE_OPT_MAXLEN)
- copylen = DCCP_SINGLE_OPT_MAXLEN;
-
- /*
- * RFC 4340, 12.2: Encode the Nonce Echo for this Ack Vector via
- * its type; ack_nonce is the sum of all individual buf_nonce's.
- */
- nonce ^= av->av_buf_nonce[i];
-
- *to++ = DCCPO_ACK_VECTOR_0 + av->av_buf_nonce[i];
- *to++ = copylen + 2;
-
- /* Check if buf_head wraps */
- if (from + copylen > tail) {
- const u16 tailsize = tail - from;
-
- memcpy(to, from, tailsize);
- to += tailsize;
- len -= tailsize;
- copylen -= tailsize;
- from = av->av_buf;
- }
-
- memcpy(to, from, copylen);
- from += copylen;
- to += copylen;
- len -= copylen;
- }
- /*
- * Each sent Ack Vector is recorded in the list, as per A.2 of RFC 4340.
- */
- if (dccp_ackvec_update_records(av, dcb->dccpd_seq, nonce))
- return -ENOBUFS;
- return 0;
-}
+ to = skb_push(skb, len + 3);
+ *to++ = type;
+ *to++ = len + 3;
+ *to++ = feat;
-/**
- * dccp_insert_option_mandatory - Mandatory option (5.8.2)
- * Note that since we are using skb_push, this function needs to be called
- * _after_ inserting the option it is supposed to influence (stack order).
- */
-int dccp_insert_option_mandatory(struct sk_buff *skb)
-{
- if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
- return -1;
+ if (len)
+ memcpy(to, val, len);
- DCCP_SKB_CB(skb)->dccpd_opt_len++;
- *skb_push(skb, 1) = DCCPO_MANDATORY;
+ dccp_pr_debug("%s(%s (%d), ...), length %d\n",
+ dccp_feat_typename(type),
+ dccp_feat_name(feat), feat, len);
return 0;
}
-/**
- * dccp_insert_fn_opt - Insert single Feature-Negotiation option into @skb
- * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R
- * @feat: one out of %dccp_feature_numbers
- * @val: NN value or SP array (preferred element first) to copy
- * @len: true length of @val in bytes (excluding first element repetition)
- * @repeat_first: whether to copy the first element of @val twice
- * The last argument is used to construct Confirm options, where the preferred
- * value and the preference list appear separately (RFC 4340, 6.3.1). Preference
- * lists are kept such that the preferred entry is always first, so we only need
- * to copy twice, and avoid the overhead of cloning into a bigger array.
- */
-int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat,
- u8 *val, u8 len, bool repeat_first)
+static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
{
- u8 tot_len, *to;
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
+ struct dccp_opt_pend *opt, *next;
+ int change = 0;
+
+ /* confirm any options [NN opts] */
+ list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type,
+ opt->dccpop_feat, opt->dccpop_val,
+ opt->dccpop_len);
+ /* fear empty confirms */
+ if (opt->dccpop_val)
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ }
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
+
+ /* see which features we need to send */
+ list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
+ /* see if we need to send any confirm */
+ if (opt->dccpop_sc) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
+ opt->dccpop_feat,
+ opt->dccpop_sc->dccpoc_val,
+ opt->dccpop_sc->dccpoc_len);
+
+ BUG_ON(!opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ opt->dccpop_sc = NULL;
+ }
- /* take the `Feature' field and possible repetition into account */
- if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) {
- DCCP_WARN("length %u for feature %u too large\n", len, feat);
- return -1;
+ /* any option not confirmed, re-send it */
+ if (!opt->dccpop_conf) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type,
+ opt->dccpop_feat, opt->dccpop_val,
+ opt->dccpop_len);
+ change++;
+ }
}
- if (unlikely(val == NULL || len == 0))
- len = repeat_first = 0;
- tot_len = 3 + repeat_first + len;
+ /* Retransmit timer.
+ * If this is the master listening sock, we don't set a timer on it. It
+ * should be fine because if the dude doesn't receive our RESPONSE
+ * [which will contain the CHANGE] he will send another REQUEST which
+ * will "retrnasmit" the change.
+ */
+ if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
+ dccp_pr_debug("reset feat negotiation timer %p\n", sk);
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) {
- DCCP_WARN("packet too small for feature %d option!\n", feat);
- return -1;
+ /* XXX don't reset the timer on re-transmissions. I.e. reset it
+ * only when sending new stuff i guess. Currently the timer
+ * never backs off because on re-transmission it just resets it!
+ */
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
}
- DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len;
-
- to = skb_push(skb, tot_len);
- *to++ = type;
- *to++ = tot_len;
- *to++ = feat;
- if (repeat_first)
- *to++ = *val;
- if (len)
- memcpy(to, val, len);
return 0;
}
int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
+ if (dmsk->dccpms_send_ndp_count &&
+ dccp_insert_option_ndp(sk, skb))
return -1;
- if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
-
- /* Feature Negotiation */
- if (dccp_feat_insert_opts(dp, NULL, skb))
+ if (!dccp_packet_without_ack(skb)) {
+ if (dmsk->dccpms_send_ack_vector &&
+ dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+ dccp_insert_option_ackvec(sk, skb))
return -1;
-
- if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
- /*
- * Obtain RTT sample from Request/Response exchange.
- * This is currently used in CCID 3 initialisation.
- */
- if (dccp_insert_option_timestamp(sk, skb))
- return -1;
-
- } else if (dccp_ackvec_pending(sk) &&
- dccp_insert_option_ackvec(sk, skb)) {
- return -1;
- }
}
if (dp->dccps_hc_rx_insert_options) {
dp->dccps_hc_rx_insert_options = 0;
}
+ /* Feature negotiation */
+ /* Data packets can't do feat negotiation */
+ if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA &&
+ DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK &&
+ dccp_insert_options_feat(sk, skb))
+ return -1;
+
+ /*
+ * Obtain RTT sample from Request/Response exchange.
+ * This is currently used in CCID 3 initialisation.
+ */
+ if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST &&
+ dccp_insert_option_timestamp(sk, skb))
+ return -1;
+
if (dp->dccps_timestamp_echo != 0 &&
dccp_insert_option_timestamp_echo(dp, NULL, skb))
return -1;
{
DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- if (dccp_feat_insert_opts(NULL, dreq, skb))
- return -1;
-
if (dreq->dreq_timestamp_echo != 0 &&
dccp_insert_option_timestamp_echo(NULL, dreq, skb))
return -1;
inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
}
-/* enqueue @skb on sk_send_head for retransmission, return clone to send now */
-static struct sk_buff *dccp_skb_entail(struct sock *sk, struct sk_buff *skb)
+static void dccp_skb_entail(struct sock *sk, struct sk_buff *skb)
{
skb_set_owner_w(skb, sk);
WARN_ON(sk->sk_send_head);
sk->sk_send_head = skb;
- return skb_clone(sk->sk_send_head, gfp_any());
}
/*
struct inet_connection_sock *icsk = inet_csk(sk);
struct dccp_sock *dp = dccp_sk(sk);
u32 ccmps = dccp_determine_ccmps(dp);
- u32 cur_mps = ccmps ? min(pmtu, ccmps) : pmtu;
+ int cur_mps = ccmps ? min(pmtu, ccmps) : pmtu;
/* Account for header lengths and IPv4/v6 option overhead */
cur_mps -= (icsk->icsk_af_ops->net_header_len + icsk->icsk_ext_hdr_len +
sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext));
/*
- * Leave enough headroom for common DCCP header options.
- * This only considers options which may appear on DCCP-Data packets, as
- * per table 3 in RFC 4340, 5.8. When running out of space for other
- * options (eg. Ack Vector which can take up to 255 bytes), it is better
- * to schedule a separate Ack. Thus we leave headroom for the following:
- * - 1 byte for Slow Receiver (11.6)
- * - 6 bytes for Timestamp (13.1)
- * - 10 bytes for Timestamp Echo (13.3)
- * - 8 bytes for NDP count (7.7, when activated)
- * - 6 bytes for Data Checksum (9.3)
- * - %DCCPAV_MIN_OPTLEN bytes for Ack Vector size (11.4, when enabled)
+ * FIXME: this should come from the CCID infrastructure, where, say,
+ * TFRC will say it wants TIMESTAMPS, ELAPSED time, etc, for now lets
+ * put a rough estimate for NDP + TIMESTAMP + TIMESTAMP_ECHO + ELAPSED
+ * TIME + TFRC_OPT_LOSS_EVENT_RATE + TFRC_OPT_RECEIVE_RATE + padding to
+ * make it a multiple of 4
*/
- cur_mps -= roundup(1 + 6 + 10 + dp->dccps_send_ndp_count * 8 + 6 +
- (dp->dccps_hc_rx_ackvec ? DCCPAV_MIN_OPTLEN : 0), 4);
+
+ cur_mps -= ((5 + 6 + 10 + 6 + 6 + 6 + 3) / 4) * 4;
/* And store cached results */
icsk->icsk_pmtu_cookie = pmtu;
}
/**
- * dccp_wait_for_ccid - Await CCID send permission
+ * dccp_wait_for_ccid - Wait for ccid to tell us we can send a packet
* @sk: socket to wait for
- * @delay: timeout in jiffies
- * This is used by CCIDs which need to delay the send time in process context.
+ * @skb: current skb to pass on for waiting
+ * @delay: sleep timeout in milliseconds (> 0)
+ * This function is called by default when the socket is closed, and
+ * when a non-zero linger time is set on the socket. For consistency
*/
-static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay)
+static int dccp_wait_for_ccid(struct sock *sk, struct sk_buff *skb, int delay)
{
+ struct dccp_sock *dp = dccp_sk(sk);
DEFINE_WAIT(wait);
- long remaining;
-
- prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
- sk->sk_write_pending++;
- release_sock(sk);
+ unsigned long jiffdelay;
+ int rc;
- remaining = schedule_timeout(delay);
-
- lock_sock(sk);
- sk->sk_write_pending--;
- finish_wait(sk->sk_sleep, &wait);
+ do {
+ dccp_pr_debug("delayed send by %d msec\n", delay);
+ jiffdelay = msecs_to_jiffies(delay);
- if (signal_pending(current) || sk->sk_err)
- return -1;
- return remaining;
-}
-
-/**
- * dccp_xmit_packet - Send data packet under control of CCID
- * Transmits next-queued payload and informs CCID to account for the packet.
- */
-static void dccp_xmit_packet(struct sock *sk)
-{
- int err, len;
- struct dccp_sock *dp = dccp_sk(sk);
- struct sk_buff *skb = dccp_qpolicy_pop(sk);
+ prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
- if (unlikely(skb == NULL))
- return;
- len = skb->len;
+ sk->sk_write_pending++;
+ release_sock(sk);
+ schedule_timeout(jiffdelay);
+ lock_sock(sk);
+ sk->sk_write_pending--;
- if (sk->sk_state == DCCP_PARTOPEN) {
- const u32 cur_mps = dp->dccps_mss_cache - DCCP_FEATNEG_OVERHEAD;
- /*
- * See 8.1.5 - Handshake Completion.
- *
- * For robustness we resend Confirm options until the client has
- * entered OPEN. During the initial feature negotiation, the MPS
- * is smaller than usual, reduced by the Change/Confirm options.
- */
- if (!list_empty(&dp->dccps_featneg) && len > cur_mps) {
- DCCP_WARN("Payload too large (%d) for featneg.\n", len);
- dccp_send_ack(sk);
- dccp_feat_list_purge(&dp->dccps_featneg);
- }
+ if (sk->sk_err)
+ goto do_error;
+ if (signal_pending(current))
+ goto do_interrupted;
- inet_csk_schedule_ack(sk);
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
- inet_csk(sk)->icsk_rto,
- DCCP_RTO_MAX);
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK;
- } else if (dccp_ack_pending(sk)) {
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATAACK;
- } else {
- DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_DATA;
- }
-
- err = dccp_transmit_skb(sk, skb);
- if (err)
- dccp_pr_debug("transmit_skb() returned err=%d\n", err);
- /*
- * Register this one as sent even if an error occurred. To the remote
- * end a local packet drop is indistinguishable from network loss, i.e.
- * any local drop will eventually be reported via receiver feedback.
- */
- ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, len);
-
- /*
- * If the CCID needs to transfer additional header options out-of-band
- * (e.g. Ack Vectors or feature-negotiation options), it activates this
- * flag to schedule a Sync. The Sync will automatically incorporate all
- * currently pending header options, thus clearing the backlog.
- */
- if (dp->dccps_sync_scheduled)
- dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC);
+ rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
+ } while ((delay = rc) > 0);
+out:
+ finish_wait(sk->sk_sleep, &wait);
+ return rc;
+
+do_error:
+ rc = -EPIPE;
+ goto out;
+do_interrupted:
+ rc = -EINTR;
+ goto out;
}
-/**
- * dccp_flush_write_queue - Drain queue at end of connection
- * Since dccp_sendmsg queues packets without waiting for them to be sent, it may
- * happen that the TX queue is not empty at the end of a connection. We give the
- * HC-sender CCID a grace period of up to @time_budget jiffies. If this function
- * returns with a non-empty write queue, it will be purged later.
- */
-void dccp_flush_write_queue(struct sock *sk, long *time_budget)
+void dccp_write_xmit(struct sock *sk, int block)
{
struct dccp_sock *dp = dccp_sk(sk);
struct sk_buff *skb;
- long delay, rc;
-
- while (*time_budget > 0 && (skb = skb_peek(&sk->sk_write_queue))) {
- rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
- switch (ccid_packet_dequeue_eval(rc)) {
- case CCID_PACKET_WILL_DEQUEUE_LATER:
- /*
- * If the CCID determines when to send, the next sending
- * time is unknown or the CCID may not even send again
- * (e.g. remote host crashes or lost Ack packets).
- */
- DCCP_WARN("CCID did not manage to send all packets\n");
- return;
- case CCID_PACKET_DELAY:
- delay = msecs_to_jiffies(rc);
- if (delay > *time_budget)
- return;
- rc = dccp_wait_for_ccid(sk, delay);
- if (rc < 0)
- return;
- *time_budget -= (delay - rc);
- /* check again if we can send now */
- break;
- case CCID_PACKET_SEND_AT_ONCE:
- dccp_xmit_packet(sk);
- break;
- case CCID_PACKET_ERR:
- skb_dequeue(&sk->sk_write_queue);
- kfree_skb(skb);
- dccp_pr_debug("packet discarded due to err=%ld\n", rc);
+ while ((skb = skb_peek(&sk->sk_write_queue))) {
+ int err = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
+
+ if (err > 0) {
+ if (!block) {
+ sk_reset_timer(sk, &dp->dccps_xmit_timer,
+ msecs_to_jiffies(err)+jiffies);
+ break;
+ } else
+ err = dccp_wait_for_ccid(sk, skb, err);
+ if (err && err != -EINTR)
+ DCCP_BUG("err=%d after dccp_wait_for_ccid", err);
}
- }
-}
-void dccp_write_xmit(struct sock *sk)
-{
- struct dccp_sock *dp = dccp_sk(sk);
- struct sk_buff *skb;
+ skb_dequeue(&sk->sk_write_queue);
+ if (err == 0) {
+ struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
+ const int len = skb->len;
- while ((skb = dccp_qpolicy_top(sk))) {
- int rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk, skb);
-
- switch (ccid_packet_dequeue_eval(rc)) {
- case CCID_PACKET_WILL_DEQUEUE_LATER:
- return;
- case CCID_PACKET_DELAY:
- sk_reset_timer(sk, &dp->dccps_xmit_timer,
- jiffies + msecs_to_jiffies(rc));
- return;
- case CCID_PACKET_SEND_AT_ONCE:
- dccp_xmit_packet(sk);
- break;
- case CCID_PACKET_ERR:
- dccp_qpolicy_drop(sk, skb);
- dccp_pr_debug("packet discarded due to err=%d\n", rc);
+ if (sk->sk_state == DCCP_PARTOPEN) {
+ /* See 8.1.5. Handshake Completion */
+ inet_csk_schedule_ack(sk);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
+ inet_csk(sk)->icsk_rto,
+ DCCP_RTO_MAX);
+ dcb->dccpd_type = DCCP_PKT_DATAACK;
+ } else if (dccp_ack_pending(sk))
+ dcb->dccpd_type = DCCP_PKT_DATAACK;
+ else
+ dcb->dccpd_type = DCCP_PKT_DATA;
+
+ err = dccp_transmit_skb(sk, skb);
+ ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len);
+ if (err)
+ DCCP_BUG("err=%d after ccid_hc_tx_packet_sent",
+ err);
+ } else {
+ dccp_pr_debug("packet discarded due to err=%d\n", err);
+ kfree_skb(skb);
}
}
}
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_RESPONSE;
DCCP_SKB_CB(skb)->dccpd_seq = dreq->dreq_iss;
- /* Resolve feature dependencies resulting from choice of CCID */
- if (dccp_feat_server_ccid_dependencies(dreq))
- goto response_failed;
-
- if (dccp_insert_options_rsk(dreq, skb))
- goto response_failed;
+ if (dccp_insert_options_rsk(dreq, skb)) {
+ kfree_skb(skb);
+ return NULL;
+ }
/* Build and checksum header */
dh = dccp_zeroed_hdr(skb, dccp_header_size);
inet_rsk(req)->acked = 1;
DCCP_INC_STATS(DCCP_MIB_OUTSEGS);
return skb;
-response_failed:
- kfree_skb(skb);
- return NULL;
}
EXPORT_SYMBOL_GPL(dccp_make_response);
/*
* Do all connect socket setups that can be done AF independent.
*/
-int dccp_connect(struct sock *sk)
+static inline void dccp_connect_init(struct sock *sk)
{
- struct sk_buff *skb;
struct dccp_sock *dp = dccp_sk(sk);
struct dst_entry *dst = __sk_dst_get(sk);
struct inet_connection_sock *icsk = inet_csk(sk);
dccp_sync_mss(sk, dst_mtu(dst));
- /* do not connect if feature negotiation setup fails */
- if (dccp_feat_finalise_settings(dccp_sk(sk)))
- return -EPROTO;
-
/* Initialise GAR as per 8.5; AWL/AWH are set in dccp_transmit_skb() */
dp->dccps_gar = dp->dccps_iss;
+ icsk->icsk_retransmits = 0;
+}
+
+int dccp_connect(struct sock *sk)
+{
+ struct sk_buff *skb;
+ struct inet_connection_sock *icsk = inet_csk(sk);
+
+ dccp_connect_init(sk);
+
skb = alloc_skb(sk->sk_prot->max_header, sk->sk_allocation);
if (unlikely(skb == NULL))
return -ENOBUFS;
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_REQUEST;
- dccp_transmit_skb(sk, dccp_skb_entail(sk, skb));
+ dccp_skb_entail(sk, skb);
+ dccp_transmit_skb(sk, skb_clone(skb, GFP_KERNEL));
DCCP_INC_STATS(DCCP_MIB_ACTIVEOPENS);
/* Timer for repeating the REQUEST until an answer. */
- icsk->icsk_retransmits = 0;
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
icsk->icsk_rto, DCCP_RTO_MAX);
return 0;
DCCP_SKB_CB(skb)->dccpd_type = pkt_type;
DCCP_SKB_CB(skb)->dccpd_ack_seq = ackno;
- /*
- * Clear the flag in case the Sync was scheduled for out-of-band data,
- * such as carrying a long Ack Vector.
- */
- dccp_sk(sk)->dccps_sync_scheduled = 0;
-
dccp_transmit_skb(sk, skb);
}
DCCP_SKB_CB(skb)->dccpd_type = DCCP_PKT_CLOSE;
if (active) {
- skb = dccp_skb_entail(sk, skb);
+ dccp_write_xmit(sk, 1);
+ dccp_skb_entail(sk, skb);
+ dccp_transmit_skb(sk, skb_clone(skb, prio));
/*
* Retransmission timer for active-close: RFC 4340, 8.3 requires
* to retransmit the Close/CloseReq until the CLOSING/CLOSEREQ
*/
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
DCCP_TIMEOUT_INIT, DCCP_RTO_MAX);
- }
- dccp_transmit_skb(sk, skb);
+ } else
+ dccp_transmit_skb(sk, skb);
}
struct kfifo *fifo;
spinlock_t lock;
wait_queue_head_t wait;
- ktime_t start;
+ struct timespec tstart;
} dccpw;
-static void jdccp_write_xmit(struct sock *sk)
+static void printl(const char *fmt, ...)
{
- const struct inet_sock *inet = inet_sk(sk);
- struct ccid3_hc_tx_sock *hctx = NULL;
- struct timespec tv;
- char buf[256];
- int len, ccid = ccid_get_current_tx_ccid(dccp_sk(sk));
+ va_list args;
+ int len;
+ struct timespec now;
+ char tbuf[256];
- if (ccid == DCCPC_CCID3)
- hctx = ccid3_hc_tx_sk(sk);
+ va_start(args, fmt);
+ getnstimeofday(&now);
- if (!port || ntohs(inet->dport) == port || ntohs(inet->sport) == port) {
+ now = timespec_sub(now, dccpw.tstart);
- tv = ktime_to_timespec(ktime_sub(ktime_get(), dccpw.start));
- len = sprintf(buf, "%lu.%09lu %d.%d.%d.%d:%u %d.%d.%d.%d:%u %d",
- (unsigned long)tv.tv_sec,
- (unsigned long)tv.tv_nsec,
- NIPQUAD(inet->saddr), ntohs(inet->sport),
- NIPQUAD(inet->daddr), ntohs(inet->dport), ccid);
+ len = sprintf(tbuf, "%lu.%06lu ",
+ (unsigned long) now.tv_sec,
+ (unsigned long) now.tv_nsec / NSEC_PER_USEC);
+ len += vscnprintf(tbuf+len, sizeof(tbuf)-len, fmt, args);
+ va_end(args);
+ kfifo_put(dccpw.fifo, tbuf, len);
+ wake_up(&dccpw.wait);
+}
+
+static int jdccp_sendmsg(struct kiocb *iocb, struct sock *sk,
+ struct msghdr *msg, size_t size)
+{
+ const struct dccp_minisock *dmsk = dccp_msk(sk);
+ const struct inet_sock *inet = inet_sk(sk);
+ const struct ccid3_hc_tx_sock *hctx;
+
+ if (dmsk->dccpms_tx_ccid == DCCPC_CCID3)
+ hctx = ccid3_hc_tx_sk(sk);
+ else
+ hctx = NULL;
+
+ if (port == 0 || ntohs(inet->dport) == port ||
+ ntohs(inet->sport) == port) {
if (hctx)
- len += sprintf(buf + len, " %d %d %d %u %u %u %d",
- hctx->s, hctx->rtt, hctx->p, hctx->x_calc,
- (unsigned)(hctx->x_recv >> 6),
- (unsigned)(hctx->x >> 6), hctx->t_ipi);
-
- len += sprintf(buf + len, "\n");
- kfifo_put(dccpw.fifo, buf, len);
- wake_up(&dccpw.wait);
+ printl("%d.%d.%d.%d:%u %d.%d.%d.%d:%u %d %d %d %d %u "
+ "%llu %llu %d\n",
+ NIPQUAD(inet->saddr), ntohs(inet->sport),
+ NIPQUAD(inet->daddr), ntohs(inet->dport), size,
+ hctx->ccid3hctx_s, hctx->ccid3hctx_rtt,
+ hctx->ccid3hctx_p, hctx->ccid3hctx_x_calc,
+ hctx->ccid3hctx_x_recv >> 6,
+ hctx->ccid3hctx_x >> 6, hctx->ccid3hctx_t_ipi);
+ else
+ printl("%d.%d.%d.%d:%u %d.%d.%d.%d:%u %d\n",
+ NIPQUAD(inet->saddr), ntohs(inet->sport),
+ NIPQUAD(inet->daddr), ntohs(inet->dport), size);
}
jprobe_return();
+ return 0;
}
static struct jprobe dccp_send_probe = {
.kp = {
- .symbol_name = "dccp_write_xmit",
+ .symbol_name = "dccp_sendmsg",
},
- .entry = jdccp_write_xmit,
+ .entry = jdccp_sendmsg,
};
static int dccpprobe_open(struct inode *inode, struct file *file)
{
kfifo_reset(dccpw.fifo);
- dccpw.start = ktime_get();
+ getnstimeofday(&dccpw.tstart);
return 0;
}
case DCCP_OPEN:
if (oldstate != DCCP_OPEN)
DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
- /* Client retransmits all Confirm options until entering OPEN */
- if (oldstate == DCCP_PARTOPEN)
- dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg);
break;
case DCCP_CLOSED:
int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
struct inet_connection_sock *icsk = inet_csk(sk);
+ dccp_minisock_init(&dp->dccps_minisock);
+
icsk->icsk_rto = DCCP_TIMEOUT_INIT;
icsk->icsk_syn_retries = sysctl_dccp_request_retries;
sk->sk_state = DCCP_CLOSED;
sk->sk_write_space = dccp_write_space;
icsk->icsk_sync_mss = dccp_sync_mss;
- dp->dccps_mss_cache = TCP_MIN_RCVMSS;
+ dp->dccps_mss_cache = 536;
dp->dccps_rate_last = jiffies;
dp->dccps_role = DCCP_ROLE_UNDEFINED;
dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
- dp->dccps_tx_qlen = sysctl_dccp_tx_qlen;
+ dp->dccps_l_ack_ratio = dp->dccps_r_ack_ratio = 1;
dccp_init_xmit_timers(sk);
- INIT_LIST_HEAD(&dp->dccps_featneg);
- /* control socket doesn't need feat nego */
- if (likely(ctl_sock_initialized))
- return dccp_feat_init(sk);
+ /*
+ * FIXME: We're hardcoding the CCID, and doing this at this point makes
+ * the listening (master) sock get CCID control blocks, which is not
+ * necessary, but for now, to not mess with the test userspace apps,
+ * lets leave it here, later the real solution is to do this in a
+ * setsockopt(CCIDs-I-want/accept). -acme
+ */
+ if (likely(ctl_sock_initialized)) {
+ int rc = dccp_feat_init(dmsk);
+
+ if (rc)
+ return rc;
+
+ if (dmsk->dccpms_send_ack_vector) {
+ dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(GFP_KERNEL);
+ if (dp->dccps_hc_rx_ackvec == NULL)
+ return -ENOMEM;
+ }
+ dp->dccps_hc_rx_ccid = ccid_hc_rx_new(dmsk->dccpms_rx_ccid,
+ sk, GFP_KERNEL);
+ dp->dccps_hc_tx_ccid = ccid_hc_tx_new(dmsk->dccpms_tx_ccid,
+ sk, GFP_KERNEL);
+ if (unlikely(dp->dccps_hc_rx_ccid == NULL ||
+ dp->dccps_hc_tx_ccid == NULL)) {
+ ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
+ ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
+ if (dmsk->dccpms_send_ack_vector) {
+ dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
+ dp->dccps_hc_rx_ackvec = NULL;
+ }
+ dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
+ return -ENOMEM;
+ }
+ } else {
+ /* control socket doesn't need feat nego */
+ INIT_LIST_HEAD(&dmsk->dccpms_pending);
+ INIT_LIST_HEAD(&dmsk->dccpms_conf);
+ }
+
return 0;
}
void dccp_destroy_sock(struct sock *sk)
{
struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
/*
* DCCP doesn't use sk_write_queue, just sk_send_head
kfree(dp->dccps_service_list);
dp->dccps_service_list = NULL;
- if (dp->dccps_hc_rx_ackvec != NULL) {
+ if (dmsk->dccpms_send_ack_vector) {
dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
dp->dccps_hc_rx_ackvec = NULL;
}
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
/* clean up feature negotiation state */
- dccp_feat_list_purge(&dp->dccps_featneg);
+ dccp_feat_clean(dmsk);
}
EXPORT_SYMBOL_GPL(dccp_destroy_sock);
struct dccp_sock *dp = dccp_sk(sk);
dp->dccps_role = DCCP_ROLE_LISTEN;
- /* do not start to listen if feature negotiation setup fails */
- if (dccp_feat_finalise_settings(dp))
- return -EPROTO;
return inet_csk_listen_start(sk, backlog);
}
return 0;
}
-static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
+/* byte 1 is feature. the rest is the preference list */
+static int dccp_setsockopt_change(struct sock *sk, int type,
+ struct dccp_so_feat __user *optval)
{
- u8 *list, len;
- int i, rc;
+ struct dccp_so_feat opt;
+ u8 *val;
+ int rc;
- if (cscov < 0 || cscov > 15)
- return -EINVAL;
+ if (copy_from_user(&opt, optval, sizeof(opt)))
+ return -EFAULT;
/*
- * Populate a list of permissible values, in the range cscov...15. This
- * is necessary since feature negotiation of single values only works if
- * both sides incidentally choose the same value. Since the list starts
- * lowest-value first, negotiation will pick the smallest shared value.
+ * rfc4340: 6.1. Change Options
*/
- if (cscov == 0)
- return 0;
- len = 16 - cscov;
-
- list = kmalloc(len, GFP_KERNEL);
- if (list == NULL)
- return -ENOBUFS;
-
- for (i = 0; i < len; i++)
- list[i] = cscov++;
-
- rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
-
- if (rc == 0) {
- if (rx)
- dccp_sk(sk)->dccps_pcrlen = cscov;
- else
- dccp_sk(sk)->dccps_pcslen = cscov;
- }
- kfree(list);
- return rc;
-}
-
-static int dccp_setsockopt_ccid(struct sock *sk, int type,
- char __user *optval, int optlen)
-{
- u8 *val;
- int rc = 0;
-
- if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
+ if (opt.dccpsf_len < 1)
return -EINVAL;
- val = kmalloc(optlen, GFP_KERNEL);
- if (val == NULL)
+ val = kmalloc(opt.dccpsf_len, GFP_KERNEL);
+ if (!val)
return -ENOMEM;
- if (copy_from_user(val, optval, optlen)) {
- kfree(val);
- return -EFAULT;
+ if (copy_from_user(val, opt.dccpsf_val, opt.dccpsf_len)) {
+ rc = -EFAULT;
+ goto out_free_val;
}
- lock_sock(sk);
- if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
- rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
+ rc = dccp_feat_change(dccp_msk(sk), type, opt.dccpsf_feat,
+ val, opt.dccpsf_len, GFP_KERNEL);
+ if (rc)
+ goto out_free_val;
- if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
- rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
- release_sock(sk);
+out:
+ return rc;
+out_free_val:
kfree(val);
- return rc;
+ goto out;
}
static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
struct dccp_sock *dp = dccp_sk(sk);
int val, err = 0;
- switch (optname) {
- case DCCP_SOCKOPT_PACKET_SIZE:
- DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
- return 0;
- case DCCP_SOCKOPT_CHANGE_L:
- case DCCP_SOCKOPT_CHANGE_R:
- DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
- return 0;
- case DCCP_SOCKOPT_CCID:
- case DCCP_SOCKOPT_RX_CCID:
- case DCCP_SOCKOPT_TX_CCID:
- return dccp_setsockopt_ccid(sk, optname, optval, optlen);
- }
-
- if (optlen < (int)sizeof(int))
+ if (optlen < sizeof(int))
return -EINVAL;
if (get_user(val, (int __user *)optval))
lock_sock(sk);
switch (optname) {
+ case DCCP_SOCKOPT_PACKET_SIZE:
+ DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
+ err = 0;
+ break;
+ case DCCP_SOCKOPT_CHANGE_L:
+ if (optlen != sizeof(struct dccp_so_feat))
+ err = -EINVAL;
+ else
+ err = dccp_setsockopt_change(sk, DCCPO_CHANGE_L,
+ (struct dccp_so_feat __user *)
+ optval);
+ break;
+ case DCCP_SOCKOPT_CHANGE_R:
+ if (optlen != sizeof(struct dccp_so_feat))
+ err = -EINVAL;
+ else
+ err = dccp_setsockopt_change(sk, DCCPO_CHANGE_R,
+ (struct dccp_so_feat __user *)
+ optval);
+ break;
case DCCP_SOCKOPT_SERVER_TIMEWAIT:
if (dp->dccps_role != DCCP_ROLE_SERVER)
err = -EOPNOTSUPP;
else
dp->dccps_server_timewait = (val != 0);
break;
- case DCCP_SOCKOPT_SEND_CSCOV:
- err = dccp_setsockopt_cscov(sk, val, false);
- break;
- case DCCP_SOCKOPT_RECV_CSCOV:
- err = dccp_setsockopt_cscov(sk, val, true);
- break;
- case DCCP_SOCKOPT_QPOLICY_ID:
- if (sk->sk_state != DCCP_CLOSED)
- err = -EISCONN;
- else if (val < 0 || val >= DCCPQ_POLICY_MAX)
+ case DCCP_SOCKOPT_SEND_CSCOV: /* sender side, RFC 4340, sec. 9.2 */
+ if (val < 0 || val > 15)
err = -EINVAL;
else
- dp->dccps_qpolicy = val;
+ dp->dccps_pcslen = val;
break;
- case DCCP_SOCKOPT_QPOLICY_TXQLEN:
- if (val < 0)
+ case DCCP_SOCKOPT_RECV_CSCOV: /* receiver side, RFC 4340 sec. 9.2.1 */
+ if (val < 0 || val > 15)
err = -EINVAL;
- else
- dp->dccps_tx_qlen = val;
+ else {
+ dp->dccps_pcrlen = val;
+ /* FIXME: add feature negotiation,
+ * ChangeL(MinimumChecksumCoverage, val) */
+ }
break;
default:
err = -ENOPROTOOPT;
break;
}
- release_sock(sk);
+ release_sock(sk);
return err;
}
case DCCP_SOCKOPT_GET_CUR_MPS:
val = dp->dccps_mss_cache;
break;
- case DCCP_SOCKOPT_AVAILABLE_CCIDS:
- return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
- case DCCP_SOCKOPT_TX_CCID:
- val = ccid_get_current_tx_ccid(dp);
- if (val < 0)
- return -ENOPROTOOPT;
- break;
- case DCCP_SOCKOPT_RX_CCID:
- val = ccid_get_current_rx_ccid(dp);
- if (val < 0)
- return -ENOPROTOOPT;
- break;
case DCCP_SOCKOPT_SERVER_TIMEWAIT:
val = dp->dccps_server_timewait;
break;
case DCCP_SOCKOPT_RECV_CSCOV:
val = dp->dccps_pcrlen;
break;
- case DCCP_SOCKOPT_QPOLICY_ID:
- val = dp->dccps_qpolicy;
- break;
- case DCCP_SOCKOPT_QPOLICY_TXQLEN:
- val = dp->dccps_tx_qlen;
- break;
case 128 ... 191:
return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
len, (u32 __user *)optval, optlen);
EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
#endif
-static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
-{
- struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
-
- /*
- * Assign an (opaque) qpolicy priority value to skb->priority.
- *
- * We are overloading this skb field for use with the qpolicy subystem.
- * The skb->priority is normally used for the SO_PRIORITY option, which
- * is initialised from sk_priority. Since the assignment of sk_priority
- * to skb->priority happens later (on layer 3), we overload this field
- * for use with queueing priorities as long as the skb is on layer 4.
- * The default priority value (if nothing is set) is 0.
- */
- skb->priority = 0;
-
- for (; cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) {
-
- if (!CMSG_OK(msg, cmsg))
- return -EINVAL;
-
- if (cmsg->cmsg_level != SOL_DCCP)
- continue;
-
- if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
- !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
- return -EINVAL;
-
- switch (cmsg->cmsg_type) {
- case DCCP_SCM_PRIORITY:
- if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
- return -EINVAL;
- skb->priority = *(__u32 *)CMSG_DATA(cmsg);
- break;
- default:
- return -EINVAL;
- }
- }
- return 0;
-}
-
int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t len)
{
lock_sock(sk);
- if (dccp_qpolicy_full(sk)) {
+ if (sysctl_dccp_tx_qlen &&
+ (sk->sk_write_queue.qlen >= sysctl_dccp_tx_qlen)) {
rc = -EAGAIN;
goto out_release;
}
if (rc != 0)
goto out_discard;
- rc = dccp_msghdr_parse(msg, skb);
- if (rc != 0)
- goto out_discard;
-
- dccp_qpolicy_push(sk, skb);
- dccp_write_xmit(sk);
+ skb_queue_tail(&sk->sk_write_queue, skb);
+ dccp_write_xmit(sk,0);
out_release:
release_sock(sk);
return rc ? : len;
/* Check zero linger _after_ checking for unread data. */
sk->sk_prot->disconnect(sk, 0);
} else if (sk->sk_state != DCCP_CLOSED) {
- /*
- * Normal connection termination. May need to wait if there are
- * still packets in the TX queue that are delayed by the CCID.
- */
- dccp_flush_write_queue(sk, &timeout);
dccp_terminate_connection(sk);
}
- /*
- * Flush write queue. This may be necessary in several cases:
- * - we have been closed by the peer but still have application data;
- * - abortive termination (unread data or zero linger time),
- * - normal termination but queue could not be flushed within time limit
- */
- __skb_queue_purge(&sk->sk_write_queue);
-
sk_stream_wait_close(sk, timeout);
adjudge_to_death:
+++ /dev/null
-/*
- * net/dccp/qpolicy.c
- *
- * Policy-based packet dequeueing interface for DCCP.
- *
- * Copyright (c) 2008 Tomasz Grobelny <tomasz@grobelny.oswiecenia.net>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License v2
- * as published by the Free Software Foundation.
- */
-#include "dccp.h"
-
-/*
- * Simple Dequeueing Policy:
- * If tx_qlen is different from 0, enqueue up to tx_qlen elements.
- */
-static void qpolicy_simple_push(struct sock *sk, struct sk_buff *skb)
-{
- skb_queue_tail(&sk->sk_write_queue, skb);
-}
-
-static bool qpolicy_simple_full(struct sock *sk)
-{
- return dccp_sk(sk)->dccps_tx_qlen &&
- sk->sk_write_queue.qlen >= dccp_sk(sk)->dccps_tx_qlen;
-}
-
-static struct sk_buff *qpolicy_simple_top(struct sock *sk)
-{
- return skb_peek(&sk->sk_write_queue);
-}
-
-/*
- * Priority-based Dequeueing Policy:
- * If tx_qlen is different from 0 and the queue has reached its upper bound
- * of tx_qlen elements, replace older packets lowest-priority-first.
- */
-static struct sk_buff *qpolicy_prio_best_skb(struct sock *sk)
-{
- struct sk_buff *skb, *best = NULL;
-
- skb_queue_walk(&sk->sk_write_queue, skb)
- if (best == NULL || skb->priority > best->priority)
- best = skb;
- return best;
-}
-
-static struct sk_buff *qpolicy_prio_worst_skb(struct sock *sk)
-{
- struct sk_buff *skb, *worst = NULL;
-
- skb_queue_walk(&sk->sk_write_queue, skb)
- if (worst == NULL || skb->priority < worst->priority)
- worst = skb;
- return worst;
-}
-
-static bool qpolicy_prio_full(struct sock *sk)
-{
- if (qpolicy_simple_full(sk))
- dccp_qpolicy_drop(sk, qpolicy_prio_worst_skb(sk));
- return false;
-}
-
-/**
- * struct dccp_qpolicy_operations - TX Packet Dequeueing Interface
- * @push: add a new @skb to the write queue
- * @full: indicates that no more packets will be admitted
- * @top: peeks at whatever the queueing policy defines as its `top'
- */
-static struct dccp_qpolicy_operations {
- void (*push) (struct sock *sk, struct sk_buff *skb);
- bool (*full) (struct sock *sk);
- struct sk_buff* (*top) (struct sock *sk);
- __be32 params;
-
-} qpol_table[DCCPQ_POLICY_MAX] = {
- [DCCPQ_POLICY_SIMPLE] = {
- .push = qpolicy_simple_push,
- .full = qpolicy_simple_full,
- .top = qpolicy_simple_top,
- .params = 0,
- },
- [DCCPQ_POLICY_PRIO] = {
- .push = qpolicy_simple_push,
- .full = qpolicy_prio_full,
- .top = qpolicy_prio_best_skb,
- .params = DCCP_SCM_PRIORITY,
- },
-};
-
-/*
- * Externally visible interface
- */
-void dccp_qpolicy_push(struct sock *sk, struct sk_buff *skb)
-{
- qpol_table[dccp_sk(sk)->dccps_qpolicy].push(sk, skb);
-}
-
-bool dccp_qpolicy_full(struct sock *sk)
-{
- return qpol_table[dccp_sk(sk)->dccps_qpolicy].full(sk);
-}
-
-void dccp_qpolicy_drop(struct sock *sk, struct sk_buff *skb)
-{
- if (skb != NULL) {
- skb_unlink(skb, &sk->sk_write_queue);
- kfree_skb(skb);
- }
-}
-
-struct sk_buff *dccp_qpolicy_top(struct sock *sk)
-{
- return qpol_table[dccp_sk(sk)->dccps_qpolicy].top(sk);
-}
-
-struct sk_buff *dccp_qpolicy_pop(struct sock *sk)
-{
- struct sk_buff *skb = dccp_qpolicy_top(sk);
-
- /* Clear any skb fields that we used internally */
- skb->priority = 0;
-
- if (skb)
- skb_unlink(skb, &sk->sk_write_queue);
- return skb;
-}
-
-bool dccp_qpolicy_param_ok(struct sock *sk, __be32 param)
-{
- /* check if exactly one bit is set */
- if (!param || (param & (param - 1)))
- return false;
- return (qpol_table[dccp_sk(sk)->dccps_qpolicy].params & param) == param;
-}
#error This file should not be compiled without CONFIG_SYSCTL defined
#endif
-/* Boundary values */
-static int zero = 0,
- u8_max = 0xFF;
-static unsigned long seqw_min = 32;
-
static struct ctl_table dccp_default_table[] = {
{
.procname = "seq_window",
- .data = &sysctl_dccp_sequence_window,
- .maxlen = sizeof(sysctl_dccp_sequence_window),
+ .data = &sysctl_dccp_feat_sequence_window,
+ .maxlen = sizeof(sysctl_dccp_feat_sequence_window),
.mode = 0644,
- .proc_handler = proc_doulongvec_minmax,
- .extra1 = &seqw_min, /* RFC 4340, 7.5.2 */
+ .proc_handler = proc_dointvec,
},
{
.procname = "rx_ccid",
- .data = &sysctl_dccp_rx_ccid,
- .maxlen = sizeof(sysctl_dccp_rx_ccid),
+ .data = &sysctl_dccp_feat_rx_ccid,
+ .maxlen = sizeof(sysctl_dccp_feat_rx_ccid),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &u8_max, /* RFC 4340, 10. */
+ .proc_handler = proc_dointvec,
},
{
.procname = "tx_ccid",
- .data = &sysctl_dccp_tx_ccid,
- .maxlen = sizeof(sysctl_dccp_tx_ccid),
+ .data = &sysctl_dccp_feat_tx_ccid,
+ .maxlen = sizeof(sysctl_dccp_feat_tx_ccid),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "ack_ratio",
+ .data = &sysctl_dccp_feat_ack_ratio,
+ .maxlen = sizeof(sysctl_dccp_feat_ack_ratio),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "send_ackvec",
+ .data = &sysctl_dccp_feat_send_ack_vector,
+ .maxlen = sizeof(sysctl_dccp_feat_send_ack_vector),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "send_ndp",
+ .data = &sysctl_dccp_feat_send_ndp_count,
+ .maxlen = sizeof(sysctl_dccp_feat_send_ndp_count),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &u8_max, /* RFC 4340, 10. */
+ .proc_handler = proc_dointvec,
},
{
.procname = "request_retries",
.data = &sysctl_dccp_request_retries,
.maxlen = sizeof(sysctl_dccp_request_retries),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &u8_max,
+ .proc_handler = proc_dointvec,
},
{
.procname = "retries1",
.data = &sysctl_dccp_retries1,
.maxlen = sizeof(sysctl_dccp_retries1),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &u8_max,
+ .proc_handler = proc_dointvec,
},
{
.procname = "retries2",
.data = &sysctl_dccp_retries2,
.maxlen = sizeof(sysctl_dccp_retries2),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &u8_max,
+ .proc_handler = proc_dointvec,
},
{
.procname = "tx_qlen",
.data = &sysctl_dccp_tx_qlen,
.maxlen = sizeof(sysctl_dccp_tx_qlen),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
+ .proc_handler = proc_dointvec,
},
{
.procname = "sync_ratelimit",
{
struct inet_connection_sock *icsk = inet_csk(sk);
+ /* retransmit timer is used for feature negotiation throughout
+ * connection. In this case, no packet is re-transmitted, but rather an
+ * ack is generated and pending changes are placed into its options.
+ */
+ if (sk->sk_send_head == NULL) {
+ dccp_pr_debug("feat negotiation retransmit timeout %p\n", sk);
+ if (sk->sk_state == DCCP_OPEN)
+ dccp_send_ack(sk);
+ goto backoff;
+ }
+
/*
* More than than 4MSL (8 minutes) has passed, a RESET(aborted) was
* sent, no need to retransmit, this sock is dead.
return;
}
+backoff:
icsk->icsk_backoff++;
icsk->icsk_rto = min(icsk->icsk_rto << 1, DCCP_RTO_MAX);
sock_put(sk);
}
-/**
- * dccp_write_xmitlet - Workhorse for CCID packet dequeueing interface
- * See the comments above %ccid_dequeueing_decision for supported modes.
- */
-static void dccp_write_xmitlet(unsigned long data)
+/* Transmit-delay timer: used by the CCIDs to delay actual send time */
+static void dccp_write_xmit_timer(unsigned long data)
{
struct sock *sk = (struct sock *)data;
+ struct dccp_sock *dp = dccp_sk(sk);
bh_lock_sock(sk);
if (sock_owned_by_user(sk))
- sk_reset_timer(sk, &dccp_sk(sk)->dccps_xmit_timer, jiffies + 1);
+ sk_reset_timer(sk, &dp->dccps_xmit_timer, jiffies+1);
else
- dccp_write_xmit(sk);
+ dccp_write_xmit(sk, 0);
bh_unlock_sock(sk);
+ sock_put(sk);
}
-static void dccp_write_xmit_timer(unsigned long data)
+static void dccp_init_write_xmit_timer(struct sock *sk)
{
- dccp_write_xmitlet(data);
- sock_put((struct sock *)data);
+ struct dccp_sock *dp = dccp_sk(sk);
+
+ setup_timer(&dp->dccps_xmit_timer, dccp_write_xmit_timer,
+ (unsigned long)sk);
}
void dccp_init_xmit_timers(struct sock *sk)
{
- struct dccp_sock *dp = dccp_sk(sk);
-
- tasklet_init(&dp->dccps_xmitlet, dccp_write_xmitlet, (unsigned long)sk);
- setup_timer(&dp->dccps_xmit_timer, dccp_write_xmit_timer,
- (unsigned long)sk);
+ dccp_init_write_xmit_timer(sk);
inet_csk_init_xmit_timers(sk, &dccp_write_timer, &dccp_delack_timer,
&dccp_keepalive_timer);
}
{
s64 delta = ktime_us_delta(ktime_get_real(), dccp_timestamp_seed);
- return div_u64(delta, DCCP_TIME_RESOLUTION);
+ do_div(delta, 10);
+ return delta;
}
EXPORT_SYMBOL_GPL(dccp_timestamp);
}
}
+/* Numbers are taken from RFC3390.
+ *
+ * John Heffner states:
+ *
+ * The RFC specifies a window of no more than 4380 bytes
+ * unless 2*MSS > 4380. Reading the pseudocode in the RFC
+ * is a bit misleading because they use a clamp at 4380 bytes
+ * rather than use a multiplier in the relevant range.
+ */
__u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
{
__u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0);
- if (!cwnd)
- cwnd = rfc3390_bytes_to_packets(tp->mss_cache);
+ if (!cwnd) {
+ if (tp->mss_cache > 1460)
+ cwnd = 2;
+ else
+ cwnd = (tp->mss_cache > 1095) ? 3 : 4;
+ }
return min_t(__u32, cwnd, tp->snd_cwnd_clamp);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff