#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 "dccp.h"
#include "feat.h"
-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 dccp_decode_value_var(const u8 *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);
const struct dccp_hdr *dh = dccp_hdr(skb);
(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;
/* 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;
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("%s rx opt: NDP count=%d\n", dccp_role(sk),
- opt_recv->dccpor_ndp);
- break;
- case DCCPO_CHANGE_L:
- /* fall through */
- case DCCPO_CHANGE_R:
- 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;
+ dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
+ (unsigned long long)opt_recv->dccpor_ndp);
break;
- case DCCPO_CONFIRM_L:
- /* fall through */
- case DCCPO_CONFIRM_R:
- if (len < 2)
- goto out_invalid_option;
- if (dccp_feat_confirm_recv(sk, opt, *value,
- value + 1, len - 1))
- goto out_invalid_option;
+ 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:
case DCCPO_ACK_VECTOR_1:
- if (pkt_type == DCCP_PKT_DATA)
+ if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
break;
-
- if (dccp_msk(sk)->dccpms_send_ack_vector &&
+ if (dp->dccps_hc_rx_ackvec != NULL &&
dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
goto out_invalid_option;
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(*(__be32 *)value);
-
- dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp;
- dp->dccps_timestamp_time = ktime_get_real();
-
+ 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), opt_recv->dccpor_timestamp,
+ 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(*(__be32 *)value);
+ opt_val = get_unaligned((__be32 *)value);
+ opt_recv->dccpor_timestamp_echo = ntohl(opt_val);
dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
"ackno=%llu", dccp_role(sk),
(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(*(__be16 *)(value + 4));
- else
- elapsed_time = ntohl(*(__be32 *)(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);
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(*(__be16 *)value);
- else
- elapsed_time = ntohl(*(__be32 *)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("%s rx opt: ELAPSED_TIME=%d\n",
dccp_role(sk), elapsed_time);
break;
- /*
- * 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.
- */
case 128 ... 191: {
const u16 idx = value - options;
"implemented, ignoring", sk, opt, len);
break;
}
-
+ignore_option:
if (opt != DCCPO_MANDATORY)
mandatory = 0;
}
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;
- DCCP_WARN("DCCP(%p): invalid option %d, len=%d", 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;
}
EXPORT_SYMBOL_GPL(dccp_parse_options);
-static void dccp_encode_value_var(const u32 value, unsigned char *to,
- const unsigned int len)
+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);
}
int dccp_insert_option(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;
EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
-static int dccp_insert_option_timestamp_echo(struct sock *sk,
+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);
__be32 tstamp_echo;
- int len, elapsed_time_len;
unsigned char *to;
- const suseconds_t delta = ktime_us_delta(ktime_get_real(),
- dp->dccps_timestamp_time);
- u32 elapsed_time = delta / 10;
+ 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;
+ }
+
elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
len = 6 + elapsed_time_len;
*to++ = DCCPO_TIMESTAMP_ECHO;
*to++ = len;
- tstamp_echo = htonl(dp->dccps_timestamp_echo);
memcpy(to, &tstamp_echo, 4);
to += 4;
memcpy(to, &var32, 4);
}
- dp->dccps_timestamp_echo = 0;
- dp->dccps_timestamp_time = ktime_set(0, 0);
return 0;
}
-static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
- u8 *val, u8 len)
+/**
+ * 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)
{
- u8 *to;
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
+ return -1;
- 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);
+ DCCP_SKB_CB(skb)->dccpd_opt_len++;
+ *skb_push(skb, 1) = DCCPO_MANDATORY;
+ 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)
+{
+ u8 tot_len, *to;
+
+ /* 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;
}
- DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
+ if (unlikely(val == NULL || len == 0))
+ len = repeat_first = 0;
+ tot_len = 3 + repeat_first + len;
- to = skb_push(skb, len + 3);
+ 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;
+
+ to = skb_push(skb, tot_len);
*to++ = type;
- *to++ = len + 3;
+ *to++ = tot_len;
*to++ = feat;
+ if (repeat_first)
+ *to++ = *val;
if (len)
memcpy(to, val, len);
-
- dccp_pr_debug("%s(%s (%d), ...), length %d\n",
- dccp_feat_typename(type),
- dccp_feat_name(feat), feat, len);
return 0;
}
-static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
+/* The length of all options needs to be a multiple of 4 (5.8) */
+static void dccp_insert_option_padding(struct sk_buff *skb)
{
- 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;
- }
+ int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
- /* 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 (padding != 0) {
+ padding = 4 - padding;
+ memset(skb_push(skb, padding), 0, padding);
+ DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
}
-
- /* 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);
-
- /* 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);
- }
-
- 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 (dmsk->dccpms_send_ndp_count &&
- dccp_insert_option_ndp(sk, skb))
+ if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb))
return -1;
- 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_DATA) {
- if (dp->dccps_timestamp_echo != 0 &&
- dccp_insert_option_timestamp_echo(sk, skb))
+ /* Feature Negotiation */
+ if (dccp_feat_insert_opts(dp, NULL, 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 (dp->dccps_hc_rx_ackvec != NULL &&
+ dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+ 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))
+ if (dp->dccps_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(dp, NULL, 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;
+ dccp_insert_option_padding(skb);
+ return 0;
+}
- /* XXX: insert other options when appropriate */
+int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
+{
+ DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
- 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 (dccp_feat_insert_opts(NULL, dreq, skb))
+ return -1;
- if (padding != 0) {
- padding = 4 - padding;
- memset(skb_push(skb, padding), 0, padding);
- DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
- }
- }
+ if (dreq->dreq_timestamp_echo != 0 &&
+ dccp_insert_option_timestamp_echo(NULL, dreq, skb))
+ return -1;
+ dccp_insert_option_padding(skb);
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff