More ECN fixes:

1) We now remove ECN-Nonce since it will no longer continue as a I-D
2) Eliminate last_tsn_echo, this tied us to an assoc not the net
   and thus we were not doing m-homing on the ECN-Echo senders side right.
3) Increment the count going out even if the TSN in lower in the pending
   ECN-Echo, this way the receiver knows exactly how many packets were
   marked even with network re-ordering
4) Fix so we DO NOT stop doing delayed sack if a ECN Echo is in queue
MFC after:	1 month

1 files changed, 33 insertions, 49 deletions

diff --git a/sys/netinet/sctp_cc_functions.c b/sys/netinet/sctp_cc_functions.c
index 28bbe5a..ddd2fd85 100644
--- a/sys/netinet/sctp_cc_functions.c
+++ b/sys/netinet/sctp_cc_functions.c
@@ -168,13 +168,6 @@ sctp_cwnd_update_after_fr(struct sctp_tcb *stcb,
 					net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
 				}
 
-				/*
-				 * Disable Nonce Sum Checking and store the
-				 * resync tsn
-				 */
-				asoc->nonce_sum_check = 0;
-				asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
-
 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
 				    stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
 				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
@@ -489,25 +482,28 @@ sctp_cwnd_update_after_timeout(struct sctp_tcb *stcb, struct sctp_nets *net)
 }
 
 static void
-sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net)
+sctp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb, struct sctp_nets *net,
+    int in_window, int num_pkt_lost)
 {
 	int old_cwnd = net->cwnd;
 
-	SCTP_STAT_INCR(sctps_ecnereducedcwnd);
-	net->ssthresh = net->cwnd / 2;
-	if (net->ssthresh < net->mtu) {
-		net->ssthresh = net->mtu;
-		/* here back off the timer as well, to slow us down */
-		net->RTO <<= 1;
-	}
-	net->cwnd = net->ssthresh;
-	SDT_PROBE(sctp, cwnd, net, ecn,
-	    stcb->asoc.my_vtag,
-	    ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
-	    net,
-	    old_cwnd, net->cwnd);
-	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
-		sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
+	if (in_window == 0) {
+		SCTP_STAT_INCR(sctps_ecnereducedcwnd);
+		net->ssthresh = net->cwnd / 2;
+		if (net->ssthresh < net->mtu) {
+			net->ssthresh = net->mtu;
+			/* here back off the timer as well, to slow us down */
+			net->RTO <<= 1;
+		}
+		net->cwnd = net->ssthresh;
+		SDT_PROBE(sctp, cwnd, net, ecn,
+		    stcb->asoc.my_vtag,
+		    ((stcb->sctp_ep->sctp_lport << 16) | (stcb->rport)),
+		    net,
+		    old_cwnd, net->cwnd);
+		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
+			sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
+		}
 	}
 }
 
@@ -888,13 +884,6 @@ sctp_hs_cwnd_update_after_fr(struct sctp_tcb *stcb,
 					net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
 				}
 
-				/*
-				 * Disable Nonce Sum Checking and store the
-				 * resync tsn
-				 */
-				asoc->nonce_sum_check = 0;
-				asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
-
 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
 				    stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
 				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
@@ -1609,13 +1598,6 @@ sctp_htcp_cwnd_update_after_fr(struct sctp_tcb *stcb,
 					net->fast_recovery_tsn = lchk->rec.data.TSN_seq - 1;
 				}
 
-				/*
-				 * Disable Nonce Sum Checking and store the
-				 * resync tsn
-				 */
-				asoc->nonce_sum_check = 0;
-				asoc->nonce_resync_tsn = asoc->fast_recovery_tsn + 1;
-
 				sctp_timer_stop(SCTP_TIMER_TYPE_SEND,
 				    stcb->sctp_ep, stcb, net, SCTP_FROM_SCTP_INDATA + SCTP_LOC_32);
 				sctp_timer_start(SCTP_TIMER_TYPE_SEND,
@@ -1673,24 +1655,26 @@ sctp_htcp_cwnd_update_after_fr_timer(struct sctp_inpcb *inp,
 
 static void
 sctp_htcp_cwnd_update_after_ecn_echo(struct sctp_tcb *stcb,
-    struct sctp_nets *net)
+    struct sctp_nets *net, int in_window, int num_pkt_lost)
 {
 	int old_cwnd;
 
 	old_cwnd = net->cwnd;
 
 	/* JRS - reset hctp as if state changed */
-	htcp_reset(&net->htcp_ca);
-	SCTP_STAT_INCR(sctps_ecnereducedcwnd);
-	net->ssthresh = htcp_recalc_ssthresh(stcb, net);
-	if (net->ssthresh < net->mtu) {
-		net->ssthresh = net->mtu;
-		/* here back off the timer as well, to slow us down */
-		net->RTO <<= 1;
-	}
-	net->cwnd = net->ssthresh;
-	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
-		sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
+	if (in_window == 0) {
+		htcp_reset(&net->htcp_ca);
+		SCTP_STAT_INCR(sctps_ecnereducedcwnd);
+		net->ssthresh = htcp_recalc_ssthresh(stcb, net);
+		if (net->ssthresh < net->mtu) {
+			net->ssthresh = net->mtu;
+			/* here back off the timer as well, to slow us down */
+			net->RTO <<= 1;
+		}
+		net->cwnd = net->ssthresh;
+		if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
+			sctp_log_cwnd(stcb, net, (net->cwnd - old_cwnd), SCTP_CWND_LOG_FROM_SAT);
+		}
 	}
 }