xnu-6153.141.1.tar.gz

[apple/xnu.git] / bsd / netinet / tcp_output.c

diff --git a/bsd/netinet/tcp_output.c b/bsd/netinet/tcp_output.c
index 6f63e40f7b226d39429bed8aca5512f5be845e36..7c1988f1f9467987fc6e330ef940e511f3ae7205 100644 (file)
--- a/bsd/netinet/tcp_output.c
+++ b/bsd/netinet/tcp_output.c
@@ -978,39 +978,47 @@ after_sack_rexmit:
         * know that foreign host supports TAO, suppress sending segment.
         */
        if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una)) {
-               if (tp->t_state != TCPS_SYN_RECEIVED || tfo_enabled(tp))
-                       flags &= ~TH_SYN;
-               off--;
-               len++;
-               if (len > 0 && tp->t_state == TCPS_SYN_SENT) {
-                       while (inp->inp_sndinprog_cnt == 0 &&
-                               tp->t_pktlist_head != NULL) {
-                               packetlist = tp->t_pktlist_head;
-                               packchain_listadd = tp->t_lastchain;
-                               packchain_sent++;
-                               TCP_PKTLIST_CLEAR(tp);
-
-                               error = tcp_ip_output(so, tp, packetlist,
-                                   packchain_listadd, tp_inp_options,
-                                   (so_options & SO_DONTROUTE),
-                                   (sack_rxmit || (sack_bytes_rxmt != 0)),
-                                   isipv6);
+               if (tp->t_state == TCPS_SYN_RECEIVED && tfo_enabled(tp) && tp->snd_nxt == tp->snd_una + 1) {
+                       /* We are sending the SYN again! */
+                       off--;
+                       len++;
+               } else {
+                       if (tp->t_state != TCPS_SYN_RECEIVED || tfo_enabled(tp)) {
+                               flags &= ~TH_SYN;
                        }
 
-                       /*
-                        * tcp was closed while we were in ip,
-                        * resume close
-                        */
-                       if (inp->inp_sndinprog_cnt == 0 &&
-                               (tp->t_flags & TF_CLOSING)) {
-                               tp->t_flags &= ~TF_CLOSING;
-                               (void) tcp_close(tp);
-                       } else {
-                               tcp_check_timer_state(tp);
+                       off--;
+                       len++;
+                       if (len > 0 && tp->t_state == TCPS_SYN_SENT) {
+                               while (inp->inp_sndinprog_cnt == 0 &&
+                                       tp->t_pktlist_head != NULL) {
+                                       packetlist = tp->t_pktlist_head;
+                                       packchain_listadd = tp->t_lastchain;
+                                       packchain_sent++;
+                                       TCP_PKTLIST_CLEAR(tp);
+
+                                       error = tcp_ip_output(so, tp, packetlist,
+                                           packchain_listadd, tp_inp_options,
+                                           (so_options & SO_DONTROUTE),
+                                           (sack_rxmit || (sack_bytes_rxmt != 0)),
+                                           isipv6);
+                               }
+
+                               /*
+                                * tcp was closed while we were in ip,
+                                * resume close
+                                */
+                               if (inp->inp_sndinprog_cnt == 0 &&
+                                       (tp->t_flags & TF_CLOSING)) {
+                                       tp->t_flags &= ~TF_CLOSING;
+                                       (void) tcp_close(tp);
+                               } else {
+                                       tcp_check_timer_state(tp);
+                               }
+                               KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END,
+                                   0,0,0,0,0);
+                               return 0;
                        }
-                       KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END,
-                           0,0,0,0,0);
-                       return 0;
                }
        }