X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/d12e16782ebf8bb779633dff9e14486293bf6d07..5eebf7385fedb1517b66b53c28e5aa6bb0a2be50:/bsd/netinet/tcp_output.c

diff --git a/bsd/netinet/tcp_output.c b/bsd/netinet/tcp_output.c
index 1eabf75c4..e9fd4814e 100644
--- a/bsd/netinet/tcp_output.c
+++ b/bsd/netinet/tcp_output.c
@@ -130,6 +130,8 @@ 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.
@@ -154,35 +156,15 @@ 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.
@@ -217,7 +199,64 @@ 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);
@@ -675,6 +714,12 @@ 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;
@@ -701,7 +746,13 @@ 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
@@ -953,7 +1004,7 @@ 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
@@ -1057,9 +1108,10 @@ 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);
 }