The branch main has been updated by tuexen:
URL:
https://cgit.FreeBSD.org/src/commit/?id=c91ae48a25edd426efc49ade14fb675e07a0f5ed
commit c91ae48a25edd426efc49ade14fb675e07a0f5ed
Author: Michael Tuexen <tue...@freebsd.org>
AuthorDate: 2023-03-16 09:45:13 +0000
Commit: Michael Tuexen <tue...@freebsd.org>
CommitDate: 2023-03-16 09:45:13 +0000
sctp: don't do RTT measurements with cookies
When receiving a cookie, the receiver does not know whether the
peer retransmitted the COOKIE-ECHO chunk or not. Therefore, don't
do an RTT measurement. It might be much too long.
To overcome this limitation, one could do at least two things:
1. Bundle the INIT-ACK chunk with a HEARTBEAT chunk for doing the
RTT measurement. But this is not allowed.
2. Add a flag to the COOKIE-ECHO chunk, which indicates that it
is the initial transmission, and not a retransmission. But
this requires an RFC.
MFC after: 1 week
---
sys/netinet/sctp_input.c | 16 ----------------
1 file changed, 16 deletions(-)
diff --git a/sys/netinet/sctp_input.c b/sys/netinet/sctp_input.c
index 6299c5c7d827..3da483bdf37a 100644
--- a/sys/netinet/sctp_input.c
+++ b/sys/netinet/sctp_input.c
@@ -1351,7 +1351,6 @@ sctp_process_cookie_existing(struct mbuf *m, int iphlen,
int offset,
struct sctp_queued_to_read *sq, *nsq;
struct sctp_nets *net;
struct mbuf *op_err;
- struct timeval old;
int init_offset, initack_offset, i;
int retval;
int spec_flag = 0;
@@ -1499,16 +1498,7 @@ sctp_process_cookie_existing(struct mbuf *m, int iphlen,
int offset,
}
/* notify upper layer */
*notification = SCTP_NOTIFY_ASSOC_UP;
- /*
- * since we did not send a HB make sure we don't
- * double things
- */
- old.tv_sec = cookie->time_entered.tv_sec;
- old.tv_usec = cookie->time_entered.tv_usec;
net->hb_responded = 1;
- sctp_calculate_rto(stcb, asoc, net, &old,
- SCTP_RTT_FROM_NON_DATA);
-
if (stcb->asoc.sctp_autoclose_ticks &&
(sctp_is_feature_on(inp,
SCTP_PCB_FLAGS_AUTOCLOSE))) {
sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE,
@@ -2204,17 +2194,11 @@ sctp_process_cookie_new(struct mbuf *m, int iphlen, int
offset,
(void)SCTP_GETTIME_TIMEVAL(&stcb->asoc.time_entered);
*netp = sctp_findnet(stcb, init_src);
if (*netp != NULL) {
- struct timeval old;
-
/*
* Since we did not send a HB, make sure we don't double
* things.
*/
(*netp)->hb_responded = 1;
- /* Calculate the RTT. */
- old.tv_sec = cookie->time_entered.tv_sec;
- old.tv_usec = cookie->time_entered.tv_usec;
- sctp_calculate_rto(stcb, asoc, *netp, &old,
SCTP_RTT_FROM_NON_DATA);
}
/* respond with a COOKIE-ACK */
sctp_send_cookie_ack(stcb);
