From a2af95d72dea4ee7d5369c210247efae98aca05f Mon Sep 17 00:00:00 2001
From: Roy Marples <roy@marples.name>
Date: Thu, 26 May 2016 08:54:45 +0000
Subject: [PATCH] Don't drop DHCPv6 if we have a delegated address on router
 expiry.

---
 dhcp6.c  | 16 +++++++++++++++-
 dhcp6.h  |  1 +
 ipv6nd.c | 13 ++-----------
 3 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/dhcp6.c b/dhcp6.c
index 6beb7d86..aa6d3ce4 100644
--- a/dhcp6.c
+++ b/dhcp6.c
@@ -2520,7 +2520,7 @@ dhcp6_delegate_prefix(struct interface *ifp)
 		if (k && !carrier_warned) {
 			ifd_state = D6_STATE(ifd);
 			ipv6_addaddrs(&ifd_state->addrs);
-			if_initrt(ifd->ctx);
+			if_initrt6(ifd->ctx);
 			ipv6_buildroutes(ifd->ctx);
 			dhcp6_script_try_run(ifd, 1);
 		}
@@ -3424,6 +3424,20 @@ dhcp6_free(struct interface *ifp)
 	dhcp6_freedrop(ifp, 0, NULL);
 }
 
+void dhcp6_dropnondelegates(struct interface *ifp)
+{
+	struct dhcp6_state *state;
+	struct ipv6_addr *ia;
+
+	if ((state = D6_STATE(ifp)) == NULL)
+		return;
+	TAILQ_FOREACH(ia, &state->addrs, next) {
+		if (ia->flags & (IPV6_AF_DELEGATED | IPV6_AF_DELEGATEDPFX))
+			return;
+	}
+	dhcp6_drop(ifp, "EXPIRE6");
+}
+
 void
 dhcp6_handleifa(struct dhcpcd_ctx *ctx, int cmd, const char *ifname,
     const struct in6_addr *addr, int flags)
diff --git a/dhcp6.h b/dhcp6.h
index 3d4b8b7b..3287bbaf 100644
--- a/dhcp6.h
+++ b/dhcp6.h
@@ -248,6 +248,7 @@ void dhcp6_handleifa(struct dhcpcd_ctx *, int, const char *,
     const struct in6_addr *addr, int);
 int dhcp6_dadcompleted(const struct interface *);
 void dhcp6_drop(struct interface *, const char *);
+void dhcp6_dropnondelegates(struct interface *ifp);
 int dhcp6_dump(struct interface *);
 #else
 #define dhcp6_find_delegates(a) {}
diff --git a/ipv6nd.c b/ipv6nd.c
index 597be951..b0b65629 100644
--- a/ipv6nd.c
+++ b/ipv6nd.c
@@ -255,15 +255,6 @@ ipv6nd_makersprobe(struct interface *ifp)
 	return 0;
 }
 
-static void ipv6nd_dropdhcp6(struct interface *ifp)
-{
-	const struct dhcp6_state *d6;
-
-	/* Don't drop DHCP6 if the interface is delegated to. */
-	if ((d6 = D6_CSTATE(ifp)) != NULL && d6->state != DH6S_DELEGATED)
-		dhcp6_drop(ifp, "EXPIRE6");
-}
-
 static void
 ipv6nd_sendrsprobe(void *arg)
 {
@@ -327,7 +318,7 @@ ipv6nd_sendrsprobe(void *arg)
 		logger(ifp->ctx, LOG_WARNING,
 		    "%s: no IPv6 Routers available", ifp->name);
 		ipv6nd_drop(ifp);
-		ipv6nd_dropdhcp6(ifp);
+		dhcp6_dropnondelegates(ifp);
 	}
 }
 
@@ -1392,7 +1383,7 @@ ipv6nd_expirera(void *arg)
 
 	/* No valid routers? Kill any DHCPv6. */
 	if (!validone)
-		ipv6nd_dropdhcp6(ifp);
+		dhcp6_dropnondelegates(ifp);
 }
 
 void
-- 
2.47.3