* An implementation of the DCCP protocol
* Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
- * Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
+ * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz>
*
* 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; either version
* 2 of the License, or (at your option) any later version.
*/
-#include <linux/config.h>
#include <linux/dccp.h>
#include <linux/module.h>
#include <linux/types.h>
+#include <asm/unaligned.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
+#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
-static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
- struct sock *sk,
- const u64 ackno,
- const unsigned char len,
- const unsigned char *vector);
-
-/* stores the default values for new connection. may be changed with sysctl */
-static const struct dccp_options dccpo_default_values = {
- .dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
- .dccpo_ccid = DCCPF_INITIAL_CCID,
- .dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
- .dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
-};
-
-void dccp_options_init(struct dccp_options *dccpo)
+u64 dccp_decode_value_var(const u8 *bf, const u8 len)
{
- memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo));
-}
-
-static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
-{
- u32 value = 0;
+ u64 value = 0;
+ if (len >= DCCP_OPTVAL_MAXLEN)
+ value += ((u64)*bf++) << 40;
+ if (len > 4)
+ value += ((u64)*bf++) << 32;
if (len > 3)
- value += *bf++ << 24;
+ value += ((u64)*bf++) << 24;
if (len > 2)
- value += *bf++ << 16;
+ value += ((u64)*bf++) << 16;
if (len > 1)
- value += *bf++ << 8;
+ value += ((u64)*bf++) << 8;
if (len > 0)
value += *bf;
return value;
}
-int dccp_parse_options(struct sock *sk, struct sk_buff *skb)
+/**
+ * dccp_parse_options - Parse DCCP options present in @skb
+ * @sk: client|server|listening dccp socket (when @dreq != NULL)
+ * @dreq: request socket to use during connection setup, or NULL
+ */
+int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
+ struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
-#ifdef CONFIG_IP_DCCP_DEBUG
- const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT rx opt: " : "server rx opt: ";
-#endif
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 +
(dh->dccph_doff * 4);
struct dccp_options_received *opt_recv = &dp->dccps_options_received;
unsigned char opt, len;
- unsigned char *value;
+ unsigned char *uninitialized_var(value);
u32 elapsed_time;
+ __be32 opt_val;
+ int rc;
+ int mandatory = 0;
memset(opt_recv, 0, sizeof(*opt_recv));
+ opt = len = 0;
while (opt_ptr != opt_end) {
opt = *opt_ptr++;
len = 0;
/* Check if this isn't a single byte option */
if (opt > DCCPO_MAX_RESERVED) {
if (opt_ptr == opt_end)
- goto out_invalid_option;
+ goto out_nonsensical_length;
len = *opt_ptr++;
- if (len < 3)
- goto out_invalid_option;
+ if (len < 2)
+ goto out_nonsensical_length;
/*
* Remove the type and len fields, leaving
* just the value size
opt_ptr += len;
if (opt_ptr > opt_end)
- goto out_invalid_option;
+ goto out_nonsensical_length;
}
+ /*
+ * 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 >= 128 ||
+ opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1))
+ goto ignore_option;
+
switch (opt) {
case DCCPO_PADDING:
break;
+ case DCCPO_MANDATORY:
+ if (mandatory)
+ goto out_invalid_option;
+ if (pkt_type != DCCP_PKT_DATA)
+ mandatory = 1;
+ break;
case DCCPO_NDP_COUNT:
- if (len > 3)
+ if (len > 6)
goto out_invalid_option;
opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
- dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
- opt_recv->dccpor_ndp);
+ 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 */
+ break;
+ rc = dccp_feat_parse_options(sk, dreq, mandatory, opt,
+ *value, value + 1, len - 1);
+ if (rc)
+ goto out_featneg_failed;
break;
case DCCPO_ACK_VECTOR_0:
- if (len > DCCP_MAX_ACK_VECTOR_LEN)
+ case DCCPO_ACK_VECTOR_1:
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
+ break;
+ if (dp->dccps_hc_rx_ackvec != NULL &&
+ dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
goto out_invalid_option;
-
- if (pkt_type == DCCP_PKT_DATA)
- continue;
-
- opt_recv->dccpor_ack_vector_len = len;
- opt_recv->dccpor_ack_vector_idx = value - options;
-
- dccp_pr_debug("%sACK vector 0, len=%d, ack_ackno=%llu\n",
- debug_prefix, len,
- (unsigned long long)
- DCCP_SKB_CB(skb)->dccpd_ack_seq);
- dccp_ackvector_print(DCCP_SKB_CB(skb)->dccpd_ack_seq,
- value, len);
- dccp_ackpkts_check_rcv_ackvector(dp->dccps_hc_rx_ackpkts,
- sk,
- DCCP_SKB_CB(skb)->dccpd_ack_seq,
- len, value);
break;
case DCCPO_TIMESTAMP:
if (len != 4)
goto out_invalid_option;
+ /*
+ * RFC 4340 13.1: "The precise time corresponding to
+ * Timestamp Value zero is not specified". We use
+ * zero to indicate absence of a meaningful timestamp.
+ */
+ opt_val = get_unaligned((__be32 *)value);
+ if (unlikely(opt_val == 0)) {
+ DCCP_WARN("Timestamp with zero value\n");
+ break;
+ }
- opt_recv->dccpor_timestamp = ntohl(*(u32 *)value);
-
- dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
- dccp_timestamp(sk, &dp->dccps_timestamp_time);
-
- dccp_pr_debug("%sTIMESTAMP=%u, ackno=%llu\n",
- debug_prefix, opt_recv->dccpor_timestamp,
+ if (dreq != NULL) {
+ dreq->dreq_timestamp_echo = ntohl(opt_val);
+ dreq->dreq_timestamp_time = dccp_timestamp();
+ } else {
+ opt_recv->dccpor_timestamp =
+ dp->dccps_timestamp_echo = ntohl(opt_val);
+ dp->dccps_timestamp_time = dccp_timestamp();
+ }
+ dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
+ dccp_role(sk), ntohl(opt_val),
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
break;
if (len != 4 && len != 6 && len != 8)
goto out_invalid_option;
- opt_recv->dccpor_timestamp_echo = ntohl(*(u32 *)value);
+ opt_val = get_unaligned((__be32 *)value);
+ opt_recv->dccpor_timestamp_echo = ntohl(opt_val);
- dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, ackno=%llu, ",
- debug_prefix,
+ dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
+ "ackno=%llu", dccp_role(sk),
opt_recv->dccpor_timestamp_echo,
len + 2,
(unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
+ value += 4;
- if (len == 4)
+ if (len == 4) { /* no elapsed time included */
+ dccp_pr_debug_cat("\n");
break;
+ }
- if (len == 6)
- elapsed_time = ntohs(*(u16 *)(value + 4));
- else
- elapsed_time = ntohl(*(u32 *)(value + 4));
+ if (len == 6) { /* 2-byte elapsed time */
+ __be16 opt_val2 = get_unaligned((__be16 *)value);
+ elapsed_time = ntohs(opt_val2);
+ } else { /* 4-byte elapsed time */
+ opt_val = get_unaligned((__be32 *)value);
+ elapsed_time = ntohl(opt_val);
+ }
+
+ dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time);
/* Give precedence to the biggest ELAPSED_TIME */
if (elapsed_time > opt_recv->dccpor_elapsed_time)
opt_recv->dccpor_elapsed_time = elapsed_time;
break;
case DCCPO_ELAPSED_TIME:
- if (len != 2 && len != 4)
- goto out_invalid_option;
-
- if (pkt_type == DCCP_PKT_DATA)
- continue;
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */
+ break;
- if (len == 2)
- elapsed_time = ntohs(*(u16 *)value);
- else
- elapsed_time = ntohl(*(u32 *)value);
+ if (len == 2) {
+ __be16 opt_val2 = get_unaligned((__be16 *)value);
+ elapsed_time = ntohs(opt_val2);
+ } else if (len == 4) {
+ opt_val = get_unaligned((__be32 *)value);
+ elapsed_time = ntohl(opt_val);
+ } else {
+ goto out_invalid_option;
+ }
if (elapsed_time > opt_recv->dccpor_elapsed_time)
opt_recv->dccpor_elapsed_time = elapsed_time;
- dccp_pr_debug("%sELAPSED_TIME=%d\n", debug_prefix,
- elapsed_time);
+ dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
+ dccp_role(sk), elapsed_time);
break;
- /*
- * From draft-ietf-dccp-spec-11.txt:
- *
- * 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.
- */
case 128 ... 191: {
const u16 idx = value - options;
}
break;
default:
- pr_info("DCCP(%p): option %d(len=%d) not "
- "implemented, ignoring\n",
- sk, opt, len);
+ DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
+ "implemented, ignoring", sk, opt, len);
break;
- }
+ }
+ignore_option:
+ if (opt != DCCPO_MANDATORY)
+ mandatory = 0;
}
+ /* mandatory was the last byte in option list -> reset connection */
+ if (mandatory)
+ goto out_invalid_option;
+
+out_nonsensical_length:
+ /* RFC 4340, 5.8: ignore option and all remaining option space */
return 0;
out_invalid_option:
DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
- DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
- pr_info("DCCP(%p): invalid option %d, len=%d\n", sk, opt, len);
+ 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_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;
return -1;
}
-static void dccp_encode_value_var(const u32 value, unsigned char *to,
- const unsigned int len)
+EXPORT_SYMBOL_GPL(dccp_parse_options);
+
+void dccp_encode_value_var(const u64 value, u8 *to, const u8 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)
*to++ = (value & 0xFF);
}
-static inline int dccp_ndp_len(const int ndp)
+static inline u8 dccp_ndp_len(const u64 ndp)
{
- return likely(ndp <= 0xFF) ? 1 : ndp <= 0xFFFF ? 2 : 3;
+ if (likely(ndp <= 0xFF))
+ return 1;
+ return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6);
}
-void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
+int dccp_insert_option(struct sock *sk, struct sk_buff *skb,
const unsigned char option,
const void *value, const unsigned char len)
{
unsigned char *to;
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) {
- LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
- "%d option!\n", option);
- return;
- }
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN)
+ return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
*to++ = len + 2;
memcpy(to, value, len);
+ return 0;
}
EXPORT_SYMBOL_GPL(dccp_insert_option);
-static void dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
+static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
- int ndp = dp->dccps_ndp_count;
+ u64 ndp = dp->dccps_ndp_count;
if (dccp_non_data_packet(skb))
++dp->dccps_ndp_count;
const int len = ndp_len + 2;
if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
- return;
+ return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
*ptr++ = len;
dccp_encode_value_var(ndp, ptr, ndp_len);
}
+
+ return 0;
}
static inline int dccp_elapsed_time_len(const u32 elapsed_time)
return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
}
-void dccp_insert_option_elapsed_time(struct sock *sk,
- struct sk_buff *skb,
- u32 elapsed_time)
+int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb,
+ u32 elapsed_time)
{
-#ifdef CONFIG_IP_DCCP_DEBUG
- struct dccp_sock *dp = dccp_sk(sk);
- const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT TX opt: " : "server TX opt: ";
-#endif
const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
const int len = 2 + elapsed_time_len;
unsigned char *to;
if (elapsed_time_len == 0)
- return;
+ return 0;
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
- LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
- "insert elapsed time!\n");
- return;
- }
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+ return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
*to++ = len;
if (elapsed_time_len == 2) {
- const u16 var16 = htons((u16)elapsed_time);
+ const __be16 var16 = htons((u16)elapsed_time);
memcpy(to, &var16, 2);
} else {
- const u32 var32 = htonl(elapsed_time);
+ const __be32 var32 = htonl(elapsed_time);
memcpy(to, &var32, 4);
}
- dccp_pr_debug("%sELAPSED_TIME=%u, len=%d, seqno=%llu\n",
- debug_prefix, elapsed_time,
- len,
- (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
+ return 0;
}
EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
-static void dccp_insert_option_ack_vector(struct sock *sk, struct sk_buff *skb)
+int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
{
- struct dccp_sock *dp = dccp_sk(sk);
-#ifdef CONFIG_IP_DCCP_DEBUG
- const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT TX opt: " : "server TX opt: ";
-#endif
- struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
- int len = ap->dccpap_buf_vector_len + 2;
- struct timeval now;
- u32 elapsed_time;
- unsigned char *to, *from;
-
- dccp_timestamp(sk, &now);
- elapsed_time = timeval_delta(&now, &ap->dccpap_time) / 10;
-
- if (elapsed_time != 0)
- dccp_insert_option_elapsed_time(sk, skb, elapsed_time);
-
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
- LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to "
- "insert ACK Vector!\n");
- return;
- }
-
- /*
- * XXX: now we have just one ack vector sent record, so
- * we have to wait for it to be cleared.
- *
- * Of course this is not acceptable, but this is just for
- * basic testing now.
- */
- if (ap->dccpap_ack_seqno != DCCP_MAX_SEQNO + 1)
- return;
-
- DCCP_SKB_CB(skb)->dccpd_opt_len += len;
-
- to = skb_push(skb, len);
- *to++ = DCCPO_ACK_VECTOR_0;
- *to++ = len;
-
- len = ap->dccpap_buf_vector_len;
- from = ap->dccpap_buf + ap->dccpap_buf_head;
-
- /* Check if buf_head wraps */
- if (ap->dccpap_buf_head + len > ap->dccpap_buf_len) {
- const unsigned int tailsize = (ap->dccpap_buf_len -
- ap->dccpap_buf_head);
-
- memcpy(to, from, tailsize);
- to += tailsize;
- len -= tailsize;
- from = ap->dccpap_buf;
- }
-
- memcpy(to, from, len);
- /*
- * From draft-ietf-dccp-spec-11.txt:
- *
- * 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.
- *
- * This implemention uses just one ack record for now.
- */
- ap->dccpap_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
- ap->dccpap_ack_ptr = ap->dccpap_buf_head;
- ap->dccpap_ack_ackno = ap->dccpap_buf_ackno;
- ap->dccpap_ack_nonce = ap->dccpap_buf_nonce;
- ap->dccpap_ack_vector_len = ap->dccpap_buf_vector_len;
-
- dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
- "ack_ackno=%llu\n",
- debug_prefix, ap->dccpap_ack_vector_len,
- (unsigned long long) ap->dccpap_ack_seqno,
- (unsigned long long) ap->dccpap_ack_ackno);
-}
-
-void dccp_timestamp(const struct sock *sk, struct timeval *tv)
-{
- const struct dccp_sock *dp = dccp_sk(sk);
-
- do_gettimeofday(tv);
- tv->tv_sec -= dp->dccps_epoch.tv_sec;
- tv->tv_usec -= dp->dccps_epoch.tv_usec;
-
- while (tv->tv_usec < 0) {
- tv->tv_sec--;
- tv->tv_usec += USEC_PER_SEC;
- }
-}
-
-EXPORT_SYMBOL_GPL(dccp_timestamp);
-
-void dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
-{
- struct timeval tv;
- u32 now;
-
- dccp_timestamp(sk, &tv);
- now = timeval_usecs(&tv) / 10;
+ __be32 now = htonl(dccp_timestamp());
/* yes this will overflow but that is the point as we want a
* 10 usec 32 bit timer which mean it wraps every 11.9 hours */
- now = htonl(now);
- dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
+ return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
}
EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
-static void dccp_insert_option_timestamp_echo(struct sock *sk,
- struct sk_buff *skb)
+static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
+ struct dccp_request_sock *dreq,
+ struct sk_buff *skb)
{
- struct dccp_sock *dp = dccp_sk(sk);
-#ifdef CONFIG_IP_DCCP_DEBUG
- const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT TX opt: " : "server TX opt: ";
-#endif
- struct timeval now;
- u32 tstamp_echo;
- u32 elapsed_time;
- int len, elapsed_time_len;
+ __be32 tstamp_echo;
unsigned char *to;
+ u32 elapsed_time, elapsed_time_len, len;
+
+ if (dreq != NULL) {
+ elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
+ tstamp_echo = htonl(dreq->dreq_timestamp_echo);
+ dreq->dreq_timestamp_echo = 0;
+ } else {
+ elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
+ tstamp_echo = htonl(dp->dccps_timestamp_echo);
+ dp->dccps_timestamp_echo = 0;
+ }
- dccp_timestamp(sk, &now);
- elapsed_time = timeval_delta(&now, &dp->dccps_timestamp_time) / 10;
elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
len = 6 + elapsed_time_len;
- if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) {
- LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small to insert "
- "timestamp echo!\n");
- return;
- }
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
+ return -1;
DCCP_SKB_CB(skb)->dccpd_opt_len += len;
*to++ = DCCPO_TIMESTAMP_ECHO;
*to++ = len;
- tstamp_echo = htonl(dp->dccps_timestamp_echo);
memcpy(to, &tstamp_echo, 4);
to += 4;
-
+
if (elapsed_time_len == 2) {
- const u16 var16 = htons((u16)elapsed_time);
+ const __be16 var16 = htons((u16)elapsed_time);
memcpy(to, &var16, 2);
} else if (elapsed_time_len == 4) {
- const u32 var32 = htonl(elapsed_time);
+ const __be32 var32 = htonl(elapsed_time);
memcpy(to, &var32, 4);
}
- dccp_pr_debug("%sTIMESTAMP_ECHO=%u, len=%d, seqno=%llu\n",
- debug_prefix, dp->dccps_timestamp_echo,
- len,
- (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
-
- dp->dccps_timestamp_echo = 0;
- dp->dccps_timestamp_time.tv_sec = 0;
- dp->dccps_timestamp_time.tv_usec = 0;
+ return 0;
}
-void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
+/**
+ * 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)
{
- struct dccp_sock *dp = dccp_sk(sk);
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
+ return -1;
- DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
-
- if (dp->dccps_options.dccpo_send_ndp_count)
- dccp_insert_option_ndp(sk, skb);
+ DCCP_SKB_CB(skb)->dccpd_opt_len++;
+ *skb_push(skb, 1) = DCCPO_MANDATORY;
+ return 0;
+}
- if (!dccp_packet_without_ack(skb)) {
- if (dp->dccps_options.dccpo_send_ack_vector &&
- (dp->dccps_hc_rx_ackpkts->dccpap_buf_ackno !=
- DCCP_MAX_SEQNO + 1))
- dccp_insert_option_ack_vector(sk, skb);
- if (dp->dccps_timestamp_echo != 0)
- dccp_insert_option_timestamp_echo(sk, skb);
- }
+/**
+ * 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)
+{
+ u8 tot_len, *to;
- if (dp->dccps_hc_rx_insert_options) {
- ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb);
- dp->dccps_hc_rx_insert_options = 0;
- }
- if (dp->dccps_hc_tx_insert_options) {
- ccid_hc_tx_insert_options(dp->dccps_hc_tx_ccid, sk, skb);
- dp->dccps_hc_tx_insert_options = 0;
+ /* 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;
}
- /* XXX: insert other options when appropriate */
+ if (unlikely(val == NULL || len == 0))
+ len = repeat_first = 0;
+ tot_len = 3 + repeat_first + len;
- if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
- /* The length of all options has to be a multiple of 4 */
- int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
-
- if (padding != 0) {
- padding = 4 - padding;
- memset(skb_push(skb, padding), 0, padding);
- DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
- }
+ 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;
}
-}
+ DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len;
-struct dccp_ackpkts *dccp_ackpkts_alloc(const unsigned int len,
- const unsigned int __nocast priority)
-{
- struct dccp_ackpkts *ap = kmalloc(sizeof(*ap) + len, priority);
-
- if (ap != NULL) {
-#ifdef CONFIG_IP_DCCP_DEBUG
- memset(ap->dccpap_buf, 0xFF, len);
-#endif
- ap->dccpap_buf_len = len;
- ap->dccpap_buf_head =
- ap->dccpap_buf_tail =
- ap->dccpap_buf_len - 1;
- ap->dccpap_buf_ackno =
- ap->dccpap_ack_ackno =
- ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
- ap->dccpap_buf_nonce = ap->dccpap_buf_nonce = 0;
- ap->dccpap_ack_ptr = 0;
- ap->dccpap_time.tv_sec = 0;
- ap->dccpap_time.tv_usec = 0;
- ap->dccpap_buf_vector_len = ap->dccpap_ack_vector_len = 0;
- }
+ to = skb_push(skb, tot_len);
+ *to++ = type;
+ *to++ = tot_len;
+ *to++ = feat;
- return ap;
-}
-
-void dccp_ackpkts_free(struct dccp_ackpkts *ap)
-{
- if (ap != NULL) {
-#ifdef CONFIG_IP_DCCP_DEBUG
- memset(ap, 0xFF, sizeof(*ap) + ap->dccpap_buf_len);
-#endif
- kfree(ap);
- }
+ if (repeat_first)
+ *to++ = *val;
+ if (len)
+ memcpy(to, val, len);
+ return 0;
}
-static inline u8 dccp_ackpkts_state(const struct dccp_ackpkts *ap,
- const unsigned int index)
+/* The length of all options needs to be a multiple of 4 (5.8) */
+static void dccp_insert_option_padding(struct sk_buff *skb)
{
- return ap->dccpap_buf[index] & DCCP_ACKPKTS_STATE_MASK;
-}
+ int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
-static inline u8 dccp_ackpkts_len(const struct dccp_ackpkts *ap,
- const unsigned int index)
-{
- return ap->dccpap_buf[index] & DCCP_ACKPKTS_LEN_MASK;
+ if (padding != 0) {
+ padding = 4 - padding;
+ memset(skb_push(skb, padding), 0, padding);
+ DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
+ }
}
-/*
- * 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 inline int dccp_ackpkts_set_buf_head_state(struct dccp_ackpkts *ap,
- const unsigned int packets,
- const unsigned char state)
+int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
- unsigned int gap;
- signed long new_head;
-
- if (ap->dccpap_buf_vector_len + packets > ap->dccpap_buf_len)
- return -ENOBUFS;
-
- gap = packets - 1;
- new_head = ap->dccpap_buf_head - packets;
-
- if (new_head < 0) {
- if (gap > 0) {
- memset(ap->dccpap_buf, DCCP_ACKPKTS_STATE_NOT_RECEIVED,
- gap + new_head + 1);
- gap = -new_head;
- }
- new_head += ap->dccpap_buf_len;
- }
-
- ap->dccpap_buf_head = new_head;
+ struct dccp_sock *dp = dccp_sk(sk);
- if (gap > 0)
- memset(ap->dccpap_buf + ap->dccpap_buf_head + 1,
- DCCP_ACKPKTS_STATE_NOT_RECEIVED, gap);
+ DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- ap->dccpap_buf[ap->dccpap_buf_head] = state;
- ap->dccpap_buf_vector_len += packets;
- return 0;
-}
+ if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
+ return -1;
-/*
- * Implements the draft-ietf-dccp-spec-11.txt Appendix A
- */
-int dccp_ackpkts_add(struct dccp_ackpkts *ap, const struct sock *sk,
- u64 ackno, u8 state)
-{
- /*
- * 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 dccpap_buf.
- *
- * We may well decide to do buffer compression, etc, but for now lets
- * just drop.
- *
- * From Appendix A:
- *
- * 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.
- */
-
- /* See if this is the first ackno being inserted */
- if (ap->dccpap_buf_vector_len == 0) {
- ap->dccpap_buf[ap->dccpap_buf_head] = state;
- ap->dccpap_buf_vector_len = 1;
- } else if (after48(ackno, ap->dccpap_buf_ackno)) {
- const u64 delta = dccp_delta_seqno(ap->dccpap_buf_ackno,
- ackno);
+ if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
- /*
- * Look if the state of this packet is the same as the
- * previous ackno and if so if we can bump the head len.
- */
- if (delta == 1 &&
- dccp_ackpkts_state(ap, ap->dccpap_buf_head) == state &&
- (dccp_ackpkts_len(ap, ap->dccpap_buf_head) <
- DCCP_ACKPKTS_LEN_MASK))
- ap->dccpap_buf[ap->dccpap_buf_head]++;
- else if (dccp_ackpkts_set_buf_head_state(ap, delta, state))
- return -ENOBUFS;
- } else {
- /*
- * A.1.2. Old Packets
- *
- * When a packet with Sequence Number S arrives, and
- * S <= buf_ackno, 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, ap->dccpap_buf_ackno);
- unsigned int index = ap->dccpap_buf_head;
+ /* Feature Negotiation */
+ if (dccp_feat_insert_opts(dp, NULL, skb))
+ return -1;
- while (1) {
- const u8 len = dccp_ackpkts_len(ap, index);
- const u8 state = dccp_ackpkts_state(ap, index);
+ if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
/*
- * valid packets not yet in dccpap_buf have a reserved
- * entry, with a len equal to 0.
+ * Obtain RTT sample from Request/Response exchange.
+ * This is currently used in CCID 3 initialisation.
*/
- if (state == DCCP_ACKPKTS_STATE_NOT_RECEIVED &&
- len == 0 && delta == 0) { /* Found our
- reserved seat! */
- dccp_pr_debug("Found %llu reserved seat!\n",
- (unsigned long long) ackno);
- ap->dccpap_buf[index] = state;
- goto out;
- }
- /* len == 0 means one packet */
- if (delta < len + 1)
- goto out_duplicate;
+ if (dccp_insert_option_timestamp(sk, skb))
+ return -1;
- delta -= len + 1;
- if (++index == ap->dccpap_buf_len)
- index = 0;
+ } else if (dp->dccps_hc_rx_ackvec != NULL &&
+ dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+ dccp_insert_option_ackvec(sk, skb)) {
+ return -1;
}
}
- ap->dccpap_buf_ackno = ackno;
- dccp_timestamp(sk, &ap->dccpap_time);
-out:
- dccp_pr_debug("");
- dccp_ackpkts_print(ap);
- return 0;
-
-out_duplicate:
- /* Duplicate packet */
- dccp_pr_debug("Received a dup or already considered lost "
- "packet: %llu\n", (unsigned long long) ackno);
- return -EILSEQ;
-}
-
-#ifdef CONFIG_IP_DCCP_DEBUG
-void dccp_ackvector_print(const u64 ackno, const unsigned char *vector,
- int len)
-{
- if (!dccp_debug)
- return;
-
- printk("ACK vector len=%d, ackno=%llu |", len,
- (unsigned long long) ackno);
-
- while (len--) {
- const u8 state = (*vector & DCCP_ACKPKTS_STATE_MASK) >> 6;
- const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
-
- printk("%d,%d|", state, rl);
- ++vector;
+ if (dp->dccps_hc_rx_insert_options) {
+ if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
+ return -1;
+ dp->dccps_hc_rx_insert_options = 0;
}
- printk("\n");
-}
+ if (dp->dccps_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(dp, NULL, skb))
+ return -1;
-void dccp_ackpkts_print(const struct dccp_ackpkts *ap)
-{
- dccp_ackvector_print(ap->dccpap_buf_ackno,
- ap->dccpap_buf + ap->dccpap_buf_head,
- ap->dccpap_buf_vector_len);
-}
-#endif
-
-static void dccp_ackpkts_trow_away_ack_record(struct dccp_ackpkts *ap)
-{
- /*
- * As we're keeping track of the ack vector size
- * (dccpap_buf_vector_len) and the sent ack vector size
- * (dccpap_ack_vector_len) we don't need dccpap_buf_tail at all, but
- * keep this code here as in the future we'll implement a vector of
- * ack records, as suggested in draft-ietf-dccp-spec-11.txt
- * Appendix A. -acme
- */
-#if 0
- ap->dccpap_buf_tail = ap->dccpap_ack_ptr + 1;
- if (ap->dccpap_buf_tail >= ap->dccpap_buf_len)
- ap->dccpap_buf_tail -= ap->dccpap_buf_len;
-#endif
- ap->dccpap_buf_vector_len -= ap->dccpap_ack_vector_len;
-}
-
-void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap, struct sock *sk,
- u64 ackno)
-{
- /* Check if we actually sent an ACK vector */
- if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
- return;
-
- if (ackno == ap->dccpap_ack_seqno) {
-#ifdef CONFIG_IP_DCCP_DEBUG
- struct dccp_sock *dp = dccp_sk(sk);
- const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT rx ack: " : "server rx ack: ";
-#endif
- dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
- "ack_ackno=%llu, ACKED!\n",
- debug_prefix, 1,
- (unsigned long long) ap->dccpap_ack_seqno,
- (unsigned long long) ap->dccpap_ack_ackno);
- dccp_ackpkts_trow_away_ack_record(ap);
- ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
- }
+ dccp_insert_option_padding(skb);
+ return 0;
}
-static void dccp_ackpkts_check_rcv_ackvector(struct dccp_ackpkts *ap,
- struct sock *sk, u64 ackno,
- const unsigned char len,
- const unsigned char *vector)
+int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
{
- unsigned char i;
-
- /* Check if we actually sent an ACK vector */
- if (ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1)
- return;
- /*
- * We're in the receiver half connection, so if the received an ACK
- * vector ackno (e.g. 50) before dccpap_ack_seqno (e.g. 52), we're
- * not interested.
- *
- * Extra explanation with example:
- *
- * if we received an ACK vector with ackno 50, it can only be acking
- * 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
- */
- /* dccp_pr_debug("is %llu < %llu? ", ackno, ap->dccpap_ack_seqno); */
- if (before48(ackno, ap->dccpap_ack_seqno)) {
- /* dccp_pr_debug_cat("yes\n"); */
- return;
- }
- /* dccp_pr_debug_cat("no\n"); */
-
- i = len;
- while (i--) {
- const u8 rl = (*vector & DCCP_ACKPKTS_LEN_MASK);
- u64 ackno_end_rl;
+ DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- dccp_set_seqno(&ackno_end_rl, ackno - rl);
+ if (dccp_feat_insert_opts(NULL, dreq, skb))
+ return -1;
- /*
- * dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,
- * ap->dccpap_ack_seqno, ackno);
- */
- if (between48(ap->dccpap_ack_seqno, ackno_end_rl, ackno)) {
- const u8 state = (*vector &
- DCCP_ACKPKTS_STATE_MASK) >> 6;
- /* dccp_pr_debug_cat("yes\n"); */
-
- if (state != DCCP_ACKPKTS_STATE_NOT_RECEIVED) {
-#ifdef CONFIG_IP_DCCP_DEBUG
- struct dccp_sock *dp = dccp_sk(sk);
- const char *debug_prefix =
- dp->dccps_role == DCCP_ROLE_CLIENT ?
- "CLIENT rx ack: " : "server rx ack: ";
-#endif
- dccp_pr_debug("%sACK vector 0, len=%d, "
- "ack_seqno=%llu, ack_ackno=%llu, "
- "ACKED!\n",
- debug_prefix, len,
- (unsigned long long)
- ap->dccpap_ack_seqno,
- (unsigned long long)
- ap->dccpap_ack_ackno);
- dccp_ackpkts_trow_away_ack_record(ap);
- }
- /*
- * If dccpap_ack_seqno was not received, no problem
- * we'll send another ACK vector.
- */
- ap->dccpap_ack_seqno = DCCP_MAX_SEQNO + 1;
- break;
- }
- /* dccp_pr_debug_cat("no\n"); */
+ if (dreq->dreq_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(NULL, dreq, skb))
+ return -1;
- dccp_set_seqno(&ackno, ackno_end_rl - 1);
- ++vector;
- }
+ dccp_insert_option_padding(skb);
+ return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff