* be incorporated into the next SCTP release.
*/
+#include <linux/slab.h>
#include <linux/types.h>
#include <linux/random.h>
#include <net/sctp/sctp.h>
* given destination transport address, set RTO to the protocol
* parameter 'RTO.Initial'.
*/
- peer->last_rto = peer->rto = msecs_to_jiffies(sctp_rto_initial);
+ peer->rto = msecs_to_jiffies(sctp_rto_initial);
peer->rtt = 0;
peer->rttvar = 0;
peer->srtt = 0;
peer->rto_pending = 0;
+ peer->hb_sent = 0;
+ peer->fast_recovery = 0;
peer->last_time_heard = jiffies;
- peer->last_time_used = jiffies;
peer->last_time_ecne_reduced = jiffies;
peer->init_sent_count = 0;
INIT_LIST_HEAD(&peer->send_ready);
INIT_LIST_HEAD(&peer->transports);
+ peer->T3_rtx_timer.expires = 0;
+ peer->hb_timer.expires = 0;
+
setup_timer(&peer->T3_rtx_timer, sctp_generate_t3_rtx_event,
(unsigned long)peer);
setup_timer(&peer->hb_timer, sctp_generate_heartbeat_event,
(unsigned long)peer);
+ setup_timer(&peer->proto_unreach_timer,
+ sctp_generate_proto_unreach_event, (unsigned long)peer);
/* Initialize the 64-bit random nonce sent with heartbeat. */
get_random_bytes(&peer->hb_nonce, sizeof(peer->hb_nonce));
/* Start T3_rtx timer if it is not already running and update the heartbeat
* timer. This routine is called every time a DATA chunk is sent.
*/
-void sctp_transport_reset_timers(struct sctp_transport *transport)
+void sctp_transport_reset_timers(struct sctp_transport *transport, int force)
{
/* RFC 2960 6.3.2 Retransmission Timer Rules
*
* address.
*/
- if (!timer_pending(&transport->T3_rtx_timer))
+ if (force || !timer_pending(&transport->T3_rtx_timer))
if (!mod_timer(&transport->T3_rtx_timer,
jiffies + transport->rto))
sctp_transport_hold(transport);
if (saddr)
memcpy(&transport->saddr, saddr, sizeof(union sctp_addr));
else
- af->get_saddr(asoc, dst, daddr, &transport->saddr);
+ af->get_saddr(opt, asoc, dst, daddr, &transport->saddr);
transport->dst = dst;
if ((transport->param_flags & SPP_PMTUD_DISABLE) && transport->pathmtu) {
/* Initialize sk->sk_rcv_saddr, if the transport is the
* association's active path for getsockname().
*/
- if (asoc && (transport == asoc->peer.active_path))
+ if (asoc && (!asoc->peer.primary_path ||
+ (transport == asoc->peer.active_path)))
opt->pf->af->to_sk_saddr(&transport->saddr,
asoc->base.sk);
} else
tp->rto = tp->asoc->rto_max;
tp->rtt = rtt;
- tp->last_rto = tp->rto;
/* Reset rto_pending so that a new RTT measurement is started when a
* new data chunk is sent.
cwnd = transport->cwnd;
flight_size = transport->flight_size;
+ /* See if we need to exit Fast Recovery first */
+ if (transport->fast_recovery &&
+ TSN_lte(transport->fast_recovery_exit, sack_ctsn))
+ transport->fast_recovery = 0;
+
/* The appropriate cwnd increase algorithm is performed if, and only
- * if the cumulative TSN has advanced and the congestion window is
+ * if the cumulative TSN whould advanced and the congestion window is
* being fully utilized.
*/
- if ((transport->asoc->ctsn_ack_point >= sack_ctsn) ||
+ if (TSN_lte(sack_ctsn, transport->asoc->ctsn_ack_point) ||
(flight_size < cwnd))
return;
pmtu = transport->asoc->pathmtu;
if (cwnd <= ssthresh) {
- /* RFC 2960 7.2.1, sctpimpguide-05 2.14.2 When cwnd is less
- * than or equal to ssthresh an SCTP endpoint MUST use the
- * slow start algorithm to increase cwnd only if the current
- * congestion window is being fully utilized and an incoming
- * SACK advances the Cumulative TSN Ack Point. Only when these
- * two conditions are met can the cwnd be increased otherwise
- * the cwnd MUST not be increased. If these conditions are met
- * then cwnd MUST be increased by at most the lesser of
- * 1) the total size of the previously outstanding DATA
- * chunk(s) acknowledged, and 2) the destination's path MTU.
+ /* RFC 4960 7.2.1
+ * o When cwnd is less than or equal to ssthresh, an SCTP
+ * endpoint MUST use the slow-start algorithm to increase
+ * cwnd only if the current congestion window is being fully
+ * utilized, an incoming SACK advances the Cumulative TSN
+ * Ack Point, and the data sender is not in Fast Recovery.
+ * Only when these three conditions are met can the cwnd be
+ * increased; otherwise, the cwnd MUST not be increased.
+ * If these conditions are met, then cwnd MUST be increased
+ * by, at most, the lesser of 1) the total size of the
+ * previously outstanding DATA chunk(s) acknowledged, and
+ * 2) the destination's path MTU. This upper bound protects
+ * against the ACK-Splitting attack outlined in [SAVAGE99].
*/
+ if (transport->fast_recovery)
+ return;
+
if (bytes_acked > pmtu)
cwnd += pmtu;
else
transport->ssthresh = max(transport->cwnd/2,
4*transport->asoc->pathmtu);
transport->cwnd = transport->asoc->pathmtu;
+
+ /* T3-rtx also clears fast recovery on the transport */
+ transport->fast_recovery = 0;
break;
case SCTP_LOWER_CWND_FAST_RTX:
* cwnd = ssthresh
* partial_bytes_acked = 0
*/
+ if (transport->fast_recovery)
+ return;
+
+ /* Mark Fast recovery */
+ transport->fast_recovery = 1;
+ transport->fast_recovery_exit = transport->asoc->next_tsn - 1;
+
transport->ssthresh = max(transport->cwnd/2,
4*transport->asoc->pathmtu);
transport->cwnd = transport->ssthresh;
* congestion indications more than once every window of
* data (or more loosely more than once every round-trip time).
*/
- if ((jiffies - transport->last_time_ecne_reduced) >
- transport->rtt) {
+ if (time_after(jiffies, transport->last_time_ecne_reduced +
+ transport->rtt)) {
transport->ssthresh = max(transport->cwnd/2,
4*transport->asoc->pathmtu);
transport->cwnd = transport->ssthresh;
* to be done every RTO interval, we do it every hearbeat
* interval.
*/
- if ((jiffies - transport->last_time_used) > transport->rto)
- transport->cwnd = max(transport->cwnd/2,
- 4*transport->asoc->pathmtu);
+ transport->cwnd = max(transport->cwnd/2,
+ 4*transport->asoc->pathmtu);
break;
}
transport->cwnd, transport->ssthresh);
}
+/* Apply Max.Burst limit to the congestion window:
+ * sctpimpguide-05 2.14.2
+ * D) When the time comes for the sender to
+ * transmit new DATA chunks, the protocol parameter Max.Burst MUST
+ * first be applied to limit how many new DATA chunks may be sent.
+ * The limit is applied by adjusting cwnd as follows:
+ * if ((flightsize+ Max.Burst * MTU) < cwnd)
+ * cwnd = flightsize + Max.Burst * MTU
+ */
+
+void sctp_transport_burst_limited(struct sctp_transport *t)
+{
+ struct sctp_association *asoc = t->asoc;
+ u32 old_cwnd = t->cwnd;
+ u32 max_burst_bytes;
+
+ if (t->burst_limited)
+ return;
+
+ max_burst_bytes = t->flight_size + (asoc->max_burst * asoc->pathmtu);
+ if (max_burst_bytes < old_cwnd) {
+ t->cwnd = max_burst_bytes;
+ t->burst_limited = old_cwnd;
+ }
+}
+
+/* Restore the old cwnd congestion window, after the burst had it's
+ * desired effect.
+ */
+void sctp_transport_burst_reset(struct sctp_transport *t)
+{
+ if (t->burst_limited) {
+ t->cwnd = t->burst_limited;
+ t->burst_limited = 0;
+ }
+}
+
/* What is the next timeout value for this transport? */
unsigned long sctp_transport_timeout(struct sctp_transport *t)
{
* (see Section 6.2.1)
*/
t->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
+ t->burst_limited = 0;
t->ssthresh = asoc->peer.i.a_rwnd;
- t->last_rto = t->rto = asoc->rto_initial;
+ t->rto = asoc->rto_initial;
t->rtt = 0;
t->srtt = 0;
t->rttvar = 0;
t->flight_size = 0;
t->error_count = 0;
t->rto_pending = 0;
+ t->hb_sent = 0;
+ t->fast_recovery = 0;
/* Initialize the state information for SFR-CACC */
t->cacc.changeover_active = 0;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff