[SCTP]: Verify all the paths to a peer via heartbeat before using them.

This patch implements Path Initialization procedure as described in
Sec 2.36 of RFC4460.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 2 deletions

diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 160f62a..2763aa9 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -49,6 +49,7 @@
  */
 
 #include <linux/types.h>
+#include <linux/random.h>
 #include <net/sctp/sctp.h>
 #include <net/sctp/sm.h>
 
@@ -85,7 +86,6 @@ static struct sctp_transport *sctp_transport_init(struct sctp_transport *peer,
 
 	peer->init_sent_count = 0;
 
-	peer->state = SCTP_ACTIVE;
 	peer->param_flags = SPP_HB_DISABLE |
 			    SPP_PMTUD_ENABLE |
 			    SPP_SACKDELAY_ENABLE;
@@ -109,6 +109,9 @@ static struct sctp_transport *sctp_transport_init(struct sctp_transport *peer,
 	peer->hb_timer.function = sctp_generate_heartbeat_event;
 	peer->hb_timer.data = (unsigned long)peer;
 
+	/* Initialize the 64-bit random nonce sent with heartbeat. */
+	get_random_bytes(&peer->hb_nonce, sizeof(peer->hb_nonce));
+
 	atomic_set(&peer->refcnt, 1);
 	peer->dead = 0;
 
@@ -517,7 +520,9 @@ void sctp_transport_lower_cwnd(struct sctp_transport *transport,
 unsigned long sctp_transport_timeout(struct sctp_transport *t)
 {
 	unsigned long timeout;
-	timeout = t->hbinterval + t->rto + sctp_jitter(t->rto);
+	timeout = t->rto + sctp_jitter(t->rto);
+	if (t->state != SCTP_UNCONFIRMED)
+		timeout += t->hbinterval;
 	timeout += jiffies;
 	return timeout;
 }