From: Roy Marples <roy@marples.name>
Date: Thu, 30 May 2013 12:07:25 +0000 (+0000)
Subject: It's possible to receive an RA for an interface that has not yet
X-Git-Tag: v5.99.7~26
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0e906716c515061199e4d24a2503daa853a48862;p=thirdparty%2Fdhcpcd.git

It's possible to receive an RA for an interface that has not yet
obtained a local link address to send an RS.
If this happens, we should process the RA.
---

diff --git a/ipv6.c b/ipv6.c
index 6998c5ae..c7a515b6 100644
--- a/ipv6.c
+++ b/ipv6.c
@@ -373,13 +373,15 @@ ipv6_handleifa(int cmd, struct if_head *ifs, const char *ifname,
 	dhcp6_handleifa(cmd, ifname, addr, flags);
 }
 
-int
-ipv6_interfacehaslinklocal(const struct interface *ifp)
+const struct ll_addr *
+ipv6_linklocal(const struct interface *ifp)
 {
 	const struct ipv6_state *state;
 
 	state = IPV6_CSTATE(ifp);
-	return (state && TAILQ_FIRST(&state->ll_addrs)) ? 1 : 0;
+	if (state)
+		return TAILQ_FIRST(&state->ll_addrs);
+	return NULL;
 }
 
 int ipv6_addlinklocalcallback(struct interface *ifp,
diff --git a/ipv6.h b/ipv6.h
index c99227e4..38b9a989 100644
--- a/ipv6.h
+++ b/ipv6.h
@@ -143,7 +143,7 @@ void ipv6_handleifa(int, struct if_head *,
     const char *, const struct in6_addr *, int);
 int ipv6_handleifa_addrs(int, struct ipv6_addrhead *,
     const struct in6_addr *, int);
-int ipv6_interfacehaslinklocal(const struct interface *);
+const struct ll_addr *ipv6_linklocal(const struct interface *);
 int ipv6_addlinklocalcallback(struct interface *, void (*)(void *), void *);
 void ipv6_free(struct interface *);
 int ipv6_removesubnet(const struct interface *, struct ipv6_addr *);
diff --git a/ipv6ns.c b/ipv6ns.c
index c588bc0e..00748819 100644
--- a/ipv6ns.c
+++ b/ipv6ns.c
@@ -337,9 +337,11 @@ ipv6ns_probeaddr(void *arg)
 	if (ap->dadcallback == NULL)
 		syslog(LOG_WARNING, "%s: no callback!", ap->iface->name);
 #endif
-	if (sendmsg(unspec_sock, &sndhdr, 0) == -1)
+	if (sendmsg(unspec_sock, &sndhdr, 0) == -1) {
 		syslog(LOG_ERR, "%s: %s: sendmsg: %m",
 		    ap->iface->name, __func__);
+		return;
+	}
 
 	if (ap->dadcallback) {
 		ms_to_tv(&tv, RETRANS_TIMER);
@@ -460,15 +462,17 @@ ipv6ns_proberouter(void *arg)
 	syslog(LOG_INFO, "%s: sending IPv6 NS for %s",
 	    rap->iface->name, rap->sfrom);
 #endif
-	if (sendmsg(sock, &sndhdr, 0) == -1)
+	if (sendmsg(sock, &sndhdr, 0) == -1) {
 		syslog(LOG_ERR, "%s: %s: sendmsg: %m",
 		    rap->iface->name, __func__);
+		return;
+	}
 
 	ms_to_tv(&tv, rap->retrans == 0 ? RETRANS_TIMER : rap->retrans);
 	ms_to_tv(&rtv, MIN_RANDOM_FACTOR);
 	timeradd(&tv, &rtv, &tv);
 	rtv.tv_sec = 0;
-	rtv.tv_usec = arc4random() % (MAX_RANDOM_FACTOR_U - MIN_RANDOM_FACTOR_U);
+	rtv.tv_usec = arc4random() % (MAX_RANDOM_FACTOR_U -MIN_RANDOM_FACTOR_U);
 	timeradd(&tv, &rtv, &tv);
 	eloop_timeout_add_tv(&tv, ipv6ns_proberouter, rap);
 
diff --git a/ipv6rs.c b/ipv6rs.c
index bc151c79..29d4d94d 100644
--- a/ipv6rs.c
+++ b/ipv6rs.c
@@ -232,7 +232,7 @@ ipv6rs_sendprobe(void *arg)
 	struct in6_pktinfo pi;
 	int hoplimit = HOPLIMIT;
 
-	if (!ipv6_interfacehaslinklocal(ifp)) {
+	if (ipv6_linklocal(ifp) == NULL) {
 		syslog(LOG_DEBUG,
 		    "%s: delaying Router Soliciation for LL address",
 		    ifp->name);
@@ -596,6 +596,16 @@ ipv6rs_handledata(__unused void *arg)
 #endif
 		return;
 	}
+
+	/* We could recieve a RA before we sent a RS*/
+	if (ipv6_linklocal(ifp) == NULL) {
+#ifdef DEBUG_RS
+		syslog(LOG_DEBUG, "%s: received RA from %s (no link-local)",
+		    ifp->name, sfrom);
+#endif
+		return;
+	}
+
 	TAILQ_FOREACH(rap, &ipv6_routers, next) {
 		if (ifp == rap->iface &&
 		    memcmp(rap->from.s6_addr, from.sin6_addr.s6_addr,