From 047235d751f655120613923724587abc36921b84 Mon Sep 17 00:00:00 2001
From: Roy Marples <roy@marples.name>
Date: Mon, 19 May 2014 00:49:14 +0000
Subject: [PATCH] If a DHCPv6 lease expires as well as all IPv6 routers who
 want DHCPv6, don't restart discover.

---
 dhcp6.c  |  7 ++++++-
 dhcpcd.c |  4 ++--
 ipv6nd.c | 20 ++++++++++++++++++--
 ipv6nd.h |  3 ++-
 script.c |  6 +++---
 5 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/dhcp6.c b/dhcp6.c
index 8c27bcc4..d18da6ed 100644
--- a/dhcp6.c
+++ b/dhcp6.c
@@ -1142,7 +1142,12 @@ dhcp6_startexpire(void *arg)
 	dhcp6_freedrop_addrs(ifp, 1, NULL);
 	dhcp6_delete_delegates(ifp);
 	script_runreason(ifp, "EXPIRE6");
-	dhcp6_startdiscover(ifp);
+	if (ipv6nd_hasradhcp(ifp))
+		dhcp6_startdiscover(ifp);
+	else
+		syslog(LOG_WARNING,
+		    "%s: no advertising IPv6 router wants DHCP",
+		    ifp->name);
 }
 
 static void
diff --git a/dhcpcd.c b/dhcpcd.c
index fe869c11..5e142009 100644
--- a/dhcpcd.c
+++ b/dhcpcd.c
@@ -1001,7 +1001,7 @@ dhcpcd_handleargs(struct dhcpcd_ctx *ctx, struct fd_list *fd,
 						len++;
 					if (D6_STATE_RUNNING(ifp))
 						len++;
-					if (ipv6nd_has_ra(ifp))
+					if (ipv6nd_hasra(ifp))
 						len++;
 				}
 				if (write(fd->fd, &len, sizeof(len)) !=
@@ -1024,7 +1024,7 @@ dhcpcd_handleargs(struct dhcpcd_ctx *ctx, struct fd_list *fd,
 							len++;
 						if (D6_STATE_RUNNING(ifp))
 							len++;
-						if (ipv6nd_has_ra(ifp))
+						if (ipv6nd_hasra(ifp))
 							len++;
 					}
 				}
diff --git a/ipv6nd.c b/ipv6nd.c
index da3817b6..9977fd06 100644
--- a/ipv6nd.c
+++ b/ipv6nd.c
@@ -1022,18 +1022,34 @@ handle_flag:
 }
 
 int
-ipv6nd_has_ra(const struct interface *ifp)
+ipv6nd_hasra(const struct interface *ifp)
 {
 	const struct ra *rap;
 
 	if (ifp->ctx->ipv6) {
 		TAILQ_FOREACH(rap, ifp->ctx->ipv6->ra_routers, next)
-			if (rap->iface == ifp)
+			if (rap->iface == ifp && !rap->expired)
 				return 1;
 	}
 	return 0;
 }
 
+int
+ipv6nd_hasradhcp(const struct interface *ifp)
+{
+	const struct ra *rap;
+
+	if (ifp->ctx->ipv6) {
+		TAILQ_FOREACH(rap, ifp->ctx->ipv6->ra_routers, next) {
+			if (rap->iface == ifp &&
+			    !rap->expired &&
+			    (rap->flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)))
+				return 1;
+		}
+	}
+	return 0;
+}
+
 ssize_t
 ipv6nd_env(char **env, const char *prefix, const struct interface *ifp)
 {
diff --git a/ipv6nd.h b/ipv6nd.h
index 9dbbdf63..6c52c1fd 100644
--- a/ipv6nd.h
+++ b/ipv6nd.h
@@ -90,7 +90,8 @@ void ipv6nd_freedrop_ra(struct ra *, int);
 #define ipv6nd_drop_ra(ra) ipv6nd_freedrop_ra((ra),  1)
 ssize_t ipv6nd_free(struct interface *);
 void ipv6nd_expirera(void *arg);
-int ipv6nd_has_ra(const struct interface *);
+int ipv6nd_hasra(const struct interface *);
+int ipv6nd_hasradhcp(const struct interface *);
 void ipv6nd_handleifa(struct dhcpcd_ctx *, int,
     const char *, const struct in6_addr *, int);
 void ipv6nd_drop(struct interface *);
diff --git a/script.c b/script.c
index bbc9006a..e3f34050 100644
--- a/script.c
+++ b/script.c
@@ -249,7 +249,7 @@ make_env(const struct interface *ifp, const char *reason, char ***argv)
 #ifdef INET6
 		else if (d6_state && d6_state->new)
 			dhcp6 = 1;
-		else if (ipv6nd_has_ra(ifp))
+		else if (ipv6nd_hasra(ifp))
 			ra = 1;
 #endif
 #ifdef INET
@@ -336,7 +336,7 @@ make_env(const struct interface *ifp, const char *reason, char ***argv)
 #endif
 #ifdef INET6
 	    || (dhcp6 && d6_state && d6_state->new)
-	    || (ra && ipv6nd_has_ra(ifp))
+	    || (ra && ipv6nd_hasra(ifp))
 #endif
 	    )
 	{
@@ -557,7 +557,7 @@ send_interface(int fd, const struct interface *ifp)
 #endif
 
 #ifdef INET6
-	if (ipv6nd_has_ra(ifp)) {
+	if (ipv6nd_hasra(ifp)) {
 		if (send_interface1(fd, ifp, "ROUTERADVERT") == -1)
 			retval = -1;
 	}
-- 
2.47.3