The branch main has been updated by rscheff: URL: https://cgit.FreeBSD.org/src/commit/?id=6bf91573c153d48344d9eb66dd654e44ab2a1002
commit 6bf91573c153d48344d9eb66dd654e44ab2a1002 Author: Richard Scheffenegger <[email protected]> AuthorDate: 2022-10-06 23:50:02 +0000 Commit: Richard Scheffenegger <[email protected]> CommitDate: 2022-10-06 23:51:19 +0000 tcp: update repeat <SYN,ACK> with latest IP ECN info When multiple <SYN> segments are received, update the <SYN,ACK> sent in response to the latest IP ECN and TCP ECN information. On retransmitting the <SYN,ACK>, once ECN maxtries are done, not only disable RFC3168 ECN, but AccECN also. Reviewed By: tuexen, #transport Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D36875 --- sys/netinet/tcp_syncache.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c index 2f0e6236f612..ad1811fc68cd 100644 --- a/sys/netinet/tcp_syncache.c +++ b/sys/netinet/tcp_syncache.c @@ -514,7 +514,7 @@ syncache_timer(void *xsch) continue; } if (sc->sc_rxmits > V_tcp_ecn_maxretries) { - sc->sc_flags &= ~SCF_ECN; + sc->sc_flags &= ~SCF_ECN_MASK; } if (sc->sc_rxmits > V_tcp_syncache.rexmt_limit) { if ((s = tcp_log_addrs(&sc->sc_inc, NULL, NULL, NULL))) { @@ -1564,11 +1564,12 @@ syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th, else sc->sc_flags &= ~SCF_TIMESTAMP; /* - * Disable ECN if needed. + * Adjust ECN response if needed, e.g. different + * IP ECN field, or a fallback by the remote host. */ - if ((sc->sc_flags & SCF_ECN) && - ((tcp_get_flags(th) & (TH_ECE|TH_CWR)) != (TH_ECE|TH_CWR))) { - sc->sc_flags &= ~SCF_ECN; + if (sc->sc_flags & SCF_ECN_MASK) { + sc->sc_flags &= ~SCF_ECN_MASK; + sc->sc_flags = tcp_ecn_syncache_add(tcp_get_flags(th), iptos); } #ifdef MAC /*
