Author: rscheff Date: Thu May 21 21:15:25 2020 New Revision: 361345 URL: https://svnweb.freebsd.org/changeset/base/361345
Log: Handle ECN handshake in simultaneous open While testing simultaneous open TCP with ECN, found that negotiation fails to arrive at the expected final state. Reviewed by: tuexen (mentor) Approved by: tuexen (mentor), rgrimes (mentor) MFC after: 2 weeks Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D23373 Modified: head/sys/netinet/tcp_input.c head/sys/netinet/tcp_output.c head/sys/netinet/tcp_stacks/rack.c Modified: head/sys/netinet/tcp_input.c ============================================================================== --- head/sys/netinet/tcp_input.c Thu May 21 21:00:46 2020 (r361344) +++ head/sys/netinet/tcp_input.c Thu May 21 21:15:25 2020 (r361345) @@ -1611,6 +1611,14 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, stru * XXX this is traditional behavior, may need to be cleaned up. */ if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { + /* Handle parallel SYN for ECN */ + if (!(thflags & TH_ACK) && + ((thflags & (TH_CWR | TH_ECE)) == (TH_CWR | TH_ECE)) && + ((V_tcp_do_ecn == 1) || (V_tcp_do_ecn == 2))) { + tp->t_flags2 |= TF2_ECN_PERMIT; + tp->t_flags2 |= TF2_ECN_SND_ECE; + TCPSTAT_INC(tcps_ecn_shs); + } if ((to.to_flags & TOF_SCALE) && (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; Modified: head/sys/netinet/tcp_output.c ============================================================================== --- head/sys/netinet/tcp_output.c Thu May 21 21:00:46 2020 (r361344) +++ head/sys/netinet/tcp_output.c Thu May 21 21:15:25 2020 (r361345) @@ -1154,6 +1154,12 @@ send: } else flags |= TH_ECE|TH_CWR; } + /* Handle parallel SYN for ECN */ + if ((tp->t_state == TCPS_SYN_RECEIVED) && + (tp->t_flags2 & TF2_ECN_SND_ECE)) { + flags |= TH_ECE; + tp->t_flags2 &= ~TF2_ECN_SND_ECE; + } if (tp->t_state == TCPS_ESTABLISHED && (tp->t_flags2 & TF2_ECN_PERMIT)) { Modified: head/sys/netinet/tcp_stacks/rack.c ============================================================================== --- head/sys/netinet/tcp_stacks/rack.c Thu May 21 21:00:46 2020 (r361344) +++ head/sys/netinet/tcp_stacks/rack.c Thu May 21 21:15:25 2020 (r361345) @@ -11070,6 +11070,14 @@ rack_do_segment_nounlock(struct mbuf *m, struct tcphdr * this is traditional behavior, may need to be cleaned up. */ if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { + /* Handle parallel SYN for ECN */ + if (!(thflags & TH_ACK) && + ((thflags & (TH_CWR | TH_ECE)) == (TH_CWR | TH_ECE)) && + ((V_tcp_do_ecn == 1) || (V_tcp_do_ecn == 2))) { + tp->t_flags2 |= TF2_ECN_PERMIT; + tp->t_flags2 |= TF2_ECN_SND_ECE; + TCPSTAT_INC(tcps_ecn_shs); + } if ((to.to_flags & TOF_SCALE) && (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; @@ -13522,6 +13530,12 @@ send: flags |= TH_ECE | TH_CWR; } else flags |= TH_ECE | TH_CWR; + } + /* Handle parallel SYN for ECN */ + if ((tp->t_state == TCPS_SYN_RECEIVED) && + (tp->t_flags2 & TF2_ECN_SND_ECE)) { + flags |= TH_ECE; + tp->t_flags2 &= ~TF2_ECN_SND_ECE; } if (tp->t_state == TCPS_ESTABLISHED && (tp->t_flags2 & TF2_ECN_PERMIT)) { _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
