xnu-517.3.15.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 2bfc95262f584e1f9dd87561cf61558b5db69506..d35b91673127b1e06b101cc1554e27c0d45e44e9 100644 (file)
--- a/bsd/netinet/tcp_output.c
+++ b/bsd/netinet/tcp_output.c
@@ -133,6 +133,8 @@ extern int ipsec_bypass;
 #endif
 
 extern int slowlink_wsize;     /* window correction for slow links */
+extern u_long  route_generation;
+
 
 /*
  * Tcp output routine: figure out what should be sent and send it.
@@ -157,35 +159,15 @@ tcp_output(tp)
        int maxburst = TCP_MAXBURST;
        struct rmxp_tao *taop;
        struct rmxp_tao tao_noncached;
-#if INET6
-       int isipv6;
-#endif
-       int    last_off;
+       int    last_off = 0;
        int    m_off;
        struct mbuf *m_last = 0;
        struct mbuf *m_head = 0;
-
-
-       KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_START, 0,0,0,0,0);
 #if INET6
-       if (isipv6 = ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0)) {
-       
-               KERNEL_DEBUG(DBG_LAYER_BEG,
-                    ((tp->t_inpcb->inp_fport << 16) | tp->t_inpcb->inp_lport),
-                    (((tp->t_inpcb->in6p_laddr.s6_addr16[0] & 0xffff) << 16) |
-                     (tp->t_inpcb->in6p_faddr.s6_addr16[0] & 0xffff)),
-                    0,0,0);
-       }
-       else
+       int isipv6 = tp->t_inpcb->inp_vflag & INP_IPV6 ;
 #endif
 
-       {
-               KERNEL_DEBUG(DBG_LAYER_BEG,
-                    ((tp->t_inpcb->inp_fport << 16) | tp->t_inpcb->inp_lport),
-                    (((tp->t_inpcb->inp_laddr.s_addr & 0xffff) << 16) |
-                     (tp->t_inpcb->inp_faddr.s_addr & 0xffff)),
-                    0,0,0);
-       }
+
        /*
         * Determine length of data that should be transmitted,
         * and flags that will be used.
@@ -220,7 +202,64 @@ tcp_output(tp)
                else     
                        tp->snd_cwnd = tp->t_maxseg * ss_fltsz;
        }
+
 again:
+       KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_START, 0,0,0,0,0);
+
+#if INET6
+       if (isipv6) {
+       
+               KERNEL_DEBUG(DBG_LAYER_BEG,
+                    ((tp->t_inpcb->inp_fport << 16) | tp->t_inpcb->inp_lport),
+                    (((tp->t_inpcb->in6p_laddr.s6_addr16[0] & 0xffff) << 16) |
+                     (tp->t_inpcb->in6p_faddr.s6_addr16[0] & 0xffff)),
+                    sendalot,0,0);
+       }
+       else
+#endif
+
+       {
+               KERNEL_DEBUG(DBG_LAYER_BEG,
+                    ((tp->t_inpcb->inp_fport << 16) | tp->t_inpcb->inp_lport),
+                    (((tp->t_inpcb->inp_laddr.s_addr & 0xffff) << 16) |
+                     (tp->t_inpcb->inp_faddr.s_addr & 0xffff)),
+                    sendalot,0,0);
+       /*
+        * If the route generation id changed, we need to check that our
+        * local (source) IP address is still valid. If it isn't either
+        * return error or silently do nothing (assuming the address will
+        * come back before the TCP connection times out).
+        */
+
+      if ((tp->t_inpcb->inp_route.ro_rt != NULL &&
+           (tp->t_inpcb->inp_route.ro_rt->generation_id != route_generation)) || (tp->t_inpcb->inp_route.ro_rt == NULL)) {
+               /* check that the source address is still valid */
+               if (ifa_foraddr(tp->t_inpcb->inp_laddr.s_addr) == NULL) {
+                       if (tp->t_state >= TCPS_CLOSE_WAIT) {
+                               tcp_close(tp);
+                               return(EADDRNOTAVAIL);
+                       }
+
+                       /* set Retransmit  timer if it wasn't set
+                        * reset Persist timer and shift register as the
+                        * adversed peer window may not be valid anymore
+                        */
+
+                        if (!tp->t_timer[TCPT_REXMT]) {
+                                tp->t_timer[TCPT_REXMT] = tp->t_rxtcur;
+                               if (tp->t_timer[TCPT_PERSIST]) {
+                                       tp->t_timer[TCPT_PERSIST] = 0;
+                                       tp->t_rxtshift = 0;
+                               }
+                       }
+
+                       if (so->so_flags & SOF_NOADDRAVAIL)
+                               return(EADDRNOTAVAIL);
+                       else
+                               return(0); /* silently ignore and keep data in socket */
+               }
+        }
+       }
        sendalot = 0;
        off = tp->snd_nxt - tp->snd_una;
        win = min(tp->snd_wnd, tp->snd_cwnd);
@@ -678,6 +717,12 @@ send:
                                m->m_data += max_linkhdr;
                                m->m_len = hdrlen;
                        }
+                       /* makes sure we still have data left to be sent at this point */
+                       if (so->so_snd.sb_mb == NULL || off == -1) {
+                               if (m != NULL)  m_freem(m);
+                               error = 0; /* should we return an error? */
+                               goto out;
+                       }
                        m_copydata(so->so_snd.sb_mb, off, (int) len,
                            mtod(m, caddr_t) + hdrlen);
                        m->m_len += len;
@@ -704,7 +749,13 @@ send:
                                        m_last = NULL;
                                last_off = off + len;
                                m_head = so->so_snd.sb_mb;
-
+       
+                               /* makes sure we still have data left to be sent at this point */
+                               if (m_head == NULL) {
+                                       error = 0; /* should we return an error? */
+                                       goto out;
+                               }
+                               
                                /*
                                 * m_copym_with_hdrs will always return the last mbuf pointer and the offset into it that
                                 * it acted on to fullfill the current request, whether a valid 'hint' was passed in or not
@@ -956,7 +1007,7 @@ send:
        struct rtentry *rt;
        ip->ip_len = m->m_pkthdr.len;
 #if INET6
-       if (INP_CHECK_SOCKAF(so, AF_INET6))
+       if (isipv6)
                ip->ip_ttl = in6_selecthlim(tp->t_inpcb,
                                            tp->t_inpcb->in6p_route.ro_rt ?
                                            tp->t_inpcb->in6p_route.ro_rt->rt_ifp
@@ -1060,9 +1111,10 @@ out:
                tp->rcv_adv = tp->rcv_nxt + win;
        tp->last_ack_sent = tp->rcv_nxt;
        tp->t_flags &= ~(TF_ACKNOW|TF_DELACK);
+
+       KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0);
        if (sendalot)
                goto again;
-       KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0);
        return (0);
 }