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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-12 06:40:14 +0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-12 06:40:14 +0400
commit038a5008b2f395c85e6e71d6ddf3c684e7c405b0 (patch)
tree4735eab577e97e5a22c3141e3f60071c8065585e /net/dccp/input.c
parentdd6d1844af33acb4edd0a40b1770d091a22c94be (diff)
parent266918303226cceac7eca38ced30f15f277bd89c (diff)
downloadlinux-038a5008b2f395c85e6e71d6ddf3c684e7c405b0.tar.xz
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (867 commits) [SKY2]: status polling loop (post merge) [NET]: Fix NAPI completion handling in some drivers. [TCP]: Limit processing lost_retrans loop to work-to-do cases [TCP]: Fix lost_retrans loop vs fastpath problems [TCP]: No need to re-count fackets_out/sacked_out at RTO [TCP]: Extract tcp_match_queue_to_sack from sacktag code [TCP]: Kill almost unused variable pcount from sacktag [TCP]: Fix mark_head_lost to ignore R-bit when trying to mark L [TCP]: Add bytes_acked (ABC) clearing to FRTO too [IPv6]: Update setsockopt(IPV6_MULTICAST_IF) to support RFC 3493, try2 [NETFILTER]: x_tables: add missing ip6t_modulename aliases [NETFILTER]: nf_conntrack_tcp: fix connection reopening [QETH]: fix qeth_main.c [NETLINK]: fib_frontend build fixes [IPv6]: Export userland ND options through netlink (RDNSS support) [9P]: build fix with !CONFIG_SYSCTL [NET]: Fix dev_put() and dev_hold() comments [NET]: make netlink user -> kernel interface synchronious [NET]: unify netlink kernel socket recognition [NET]: cleanup 3rd argument in netlink_sendskb ... Fix up conflicts manually in Documentation/feature-removal-schedule.txt and my new least favourite crap, the "mod_devicetable" support in the files include/linux/mod_devicetable.h and scripts/mod/file2alias.c. (The latter files seem to be explicitly _designed_ to get conflicts when different subsystems work with them - that have an absolutely horrid lack of subsystem separation!) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'net/dccp/input.c')
-rw-r--r--net/dccp/input.c120
1 files changed, 57 insertions, 63 deletions
diff --git a/net/dccp/input.c b/net/dccp/input.c
index da6ec185ed5b..19d7e1dbd87e 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -68,7 +68,8 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
{
const struct dccp_hdr *dh = dccp_hdr(skb);
struct dccp_sock *dp = dccp_sk(sk);
- u64 lswl, lawl;
+ u64 lswl, lawl, seqno = DCCP_SKB_CB(skb)->dccpd_seq,
+ ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
/*
* Step 5: Prepare sequence numbers for Sync
@@ -84,11 +85,9 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
*/
if (dh->dccph_type == DCCP_PKT_SYNC ||
dh->dccph_type == DCCP_PKT_SYNCACK) {
- if (between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
- dp->dccps_awl, dp->dccps_awh) &&
- dccp_delta_seqno(dp->dccps_swl,
- DCCP_SKB_CB(skb)->dccpd_seq) >= 0)
- dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ if (between48(ackno, dp->dccps_awl, dp->dccps_awh) &&
+ dccp_delta_seqno(dp->dccps_swl, seqno) >= 0)
+ dccp_update_gsr(sk, seqno);
else
return -1;
}
@@ -103,9 +102,6 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
* Update S.GSR, S.SWL, S.SWH
* If P.type != Sync,
* Update S.GAR
- * Otherwise,
- * Send Sync packet acknowledging P.seqno
- * Drop packet and return
*/
lswl = dp->dccps_swl;
lawl = dp->dccps_awl;
@@ -113,35 +109,52 @@ static int dccp_check_seqno(struct sock *sk, struct sk_buff *skb)
if (dh->dccph_type == DCCP_PKT_CLOSEREQ ||
dh->dccph_type == DCCP_PKT_CLOSE ||
dh->dccph_type == DCCP_PKT_RESET) {
- lswl = dp->dccps_gsr;
- dccp_inc_seqno(&lswl);
+ lswl = ADD48(dp->dccps_gsr, 1);
lawl = dp->dccps_gar;
}
- if (between48(DCCP_SKB_CB(skb)->dccpd_seq, lswl, dp->dccps_swh) &&
- (DCCP_SKB_CB(skb)->dccpd_ack_seq == DCCP_PKT_WITHOUT_ACK_SEQ ||
- between48(DCCP_SKB_CB(skb)->dccpd_ack_seq,
- lawl, dp->dccps_awh))) {
- dccp_update_gsr(sk, DCCP_SKB_CB(skb)->dccpd_seq);
+ if (between48(seqno, lswl, dp->dccps_swh) &&
+ (ackno == DCCP_PKT_WITHOUT_ACK_SEQ ||
+ between48(ackno, lawl, dp->dccps_awh))) {
+ dccp_update_gsr(sk, seqno);
if (dh->dccph_type != DCCP_PKT_SYNC &&
- (DCCP_SKB_CB(skb)->dccpd_ack_seq !=
- DCCP_PKT_WITHOUT_ACK_SEQ))
- dp->dccps_gar = DCCP_SKB_CB(skb)->dccpd_ack_seq;
+ (ackno != DCCP_PKT_WITHOUT_ACK_SEQ))
+ dp->dccps_gar = ackno;
} else {
+ unsigned long now = jiffies;
+ /*
+ * Step 6: Check sequence numbers
+ * Otherwise,
+ * If P.type == Reset,
+ * Send Sync packet acknowledging S.GSR
+ * Otherwise,
+ * Send Sync packet acknowledging P.seqno
+ * Drop packet and return
+ *
+ * These Syncs are rate-limited as per RFC 4340, 7.5.4:
+ * at most 1 / (dccp_sync_rate_limit * HZ) Syncs per second.
+ */
+ if (time_before(now, (dp->dccps_rate_last +
+ sysctl_dccp_sync_ratelimit)))
+ return 0;
+
DCCP_WARN("DCCP: Step 6 failed for %s packet, "
"(LSWL(%llu) <= P.seqno(%llu) <= S.SWH(%llu)) and "
"(P.ackno %s or LAWL(%llu) <= P.ackno(%llu) <= S.AWH(%llu), "
"sending SYNC...\n", dccp_packet_name(dh->dccph_type),
- (unsigned long long) lswl,
- (unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq,
+ (unsigned long long) lswl, (unsigned long long) seqno,
(unsigned long long) dp->dccps_swh,
- (DCCP_SKB_CB(skb)->dccpd_ack_seq ==
- DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist" : "exists",
- (unsigned long long) lawl,
- (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq,
+ (ackno == DCCP_PKT_WITHOUT_ACK_SEQ) ? "doesn't exist"
+ : "exists",
+ (unsigned long long) lawl, (unsigned long long) ackno,
(unsigned long long) dp->dccps_awh);
- dccp_send_sync(sk, DCCP_SKB_CB(skb)->dccpd_seq, DCCP_PKT_SYNC);
+
+ dp->dccps_rate_last = now;
+
+ if (dh->dccph_type == DCCP_PKT_RESET)
+ seqno = dp->dccps_gsr;
+ dccp_send_sync(sk, seqno, DCCP_PKT_SYNC);
return -1;
}
@@ -280,6 +293,7 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
if (dh->dccph_type == DCCP_PKT_RESPONSE) {
const struct inet_connection_sock *icsk = inet_csk(sk);
struct dccp_sock *dp = dccp_sk(sk);
+ long tstamp = dccp_timestamp();
/* Stop the REQUEST timer */
inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
@@ -300,13 +314,10 @@ static int dccp_rcv_request_sent_state_process(struct sock *sk,
if (dccp_parse_options(sk, skb))
goto out_invalid_packet;
- /* Obtain RTT sample from SYN exchange (used by CCID 3) */
- if (dp->dccps_options_received.dccpor_timestamp_echo) {
- struct timeval now;
-
- dccp_timestamp(sk, &now);
- dp->dccps_syn_rtt = dccp_sample_rtt(sk, &now, NULL);
- }
+ /* 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,
@@ -540,11 +551,6 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
return 0;
}
- if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) {
- dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNCACK);
- goto discard;
- }
-
switch (sk->sk_state) {
case DCCP_CLOSED:
dcb->dccpd_reset_code = DCCP_RESET_CODE_NO_CONNECTION;
@@ -575,6 +581,9 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
sk_wake_async(sk, 0, POLL_OUT);
break;
}
+ } else if (unlikely(dh->dccph_type == DCCP_PKT_SYNC)) {
+ dccp_send_sync(sk, dcb->dccpd_seq, DCCP_PKT_SYNCACK);
+ goto discard;
}
if (!queued) {
@@ -587,37 +596,22 @@ discard:
EXPORT_SYMBOL_GPL(dccp_rcv_state_process);
/**
- * dccp_sample_rtt - Sample RTT from packet exchange
- *
- * @sk: connected dccp_sock
- * @t_recv: receive timestamp of packet with timestamp echo
- * @t_hist: packet history timestamp or NULL
+ * dccp_sample_rtt - Validate and finalise computation of RTT sample
+ * @delta: number of microseconds between packet and acknowledgment
+ * The routine is kept generic to work in different contexts. It should be
+ * called immediately when the ACK used for the RTT sample arrives.
*/
-u32 dccp_sample_rtt(struct sock *sk, struct timeval *t_recv,
- struct timeval *t_hist)
+u32 dccp_sample_rtt(struct sock *sk, long delta)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct dccp_options_received *or = &dp->dccps_options_received;
- suseconds_t delta;
-
- if (t_hist == NULL) {
- if (!or->dccpor_timestamp_echo) {
- DCCP_WARN("packet without timestamp echo\n");
- return DCCP_SANE_RTT_MAX;
- }
- timeval_sub_usecs(t_recv, or->dccpor_timestamp_echo * 10);
- delta = timeval_usecs(t_recv);
- } else
- delta = timeval_delta(t_recv, t_hist);
-
- delta -= or->dccpor_elapsed_time * 10; /* either set or 0 */
+ /* dccpor_elapsed_time is either zeroed out or set and > 0 */
+ delta -= dccp_sk(sk)->dccps_options_received.dccpor_elapsed_time * 10;
if (unlikely(delta <= 0)) {
- DCCP_WARN("unusable RTT sample %ld, using min\n", (long)delta);
+ DCCP_WARN("unusable RTT sample %ld, using min\n", delta);
return DCCP_SANE_RTT_MIN;
}
- if (unlikely(delta - (suseconds_t)DCCP_SANE_RTT_MAX > 0)) {
- DCCP_WARN("RTT sample %ld too large, using max\n", (long)delta);
+ if (unlikely(delta > DCCP_SANE_RTT_MAX)) {
+ DCCP_WARN("RTT sample %ld too large, using max\n", delta);
return DCCP_SANE_RTT_MAX;
}