From: Roy Marples <roy@marples.name>
Date: Tue, 17 Dec 2019 22:16:26 +0000 (+0000)
Subject: DHCP6: Rework delegation deprecation
X-Git-Tag: v7.2.4~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9b8fa49e98cf94e268131e5119a59b406fc34108;p=thirdparty%2Fdhcpcd.git

DHCP6: Rework delegation deprecation

Split ipv6_addaddrs out so ipv6_doaddr can operate on a single address.
Call this when deprecating delegated addresses to avoid calling
ipv6_addaddrs.

This allows a more simple ipv6_addaddrs that doesn't need to test
which address collection we are deleting from and removes DHCPv6
specific code from the generic IPv6 module.
---

diff --git a/src/dhcp6.c b/src/dhcp6.c
index b3f16b91..ed5fe8d6 100644
--- a/src/dhcp6.c
+++ b/src/dhcp6.c
@@ -2351,11 +2351,53 @@ dhcp6_findia(struct interface *ifp, struct dhcp6_message *m, size_t l,
 	return i;
 }
 
+#ifndef SMALL
+static void
+dhcp6_deprecatedele(struct ipv6_addr *ia)
+{
+	struct ipv6_addr *da, *dan, *dda;
+	struct timespec now;
+	struct dhcp6_state *state;
+
+	timespecclear(&now);
+	TAILQ_FOREACH_SAFE(da, &ia->pd_pfxs, pd_next, dan) {
+		if (ia->prefix_vltime == 0) {
+			if (da->prefix_vltime != 0)
+				da->prefix_vltime = 0;
+			else
+				continue;
+		} else if (da->prefix_pltime != 0)
+			da->prefix_pltime = 0;
+		else
+			continue;
+
+		if (ipv6_doaddr(da, &now) != -1)
+			continue;
+
+		/* Delegation deleted, forget it. */
+		TAILQ_REMOVE(&ia->pd_pfxs, da, pd_next);
+
+		/* Delete it from the interface. */
+		state = D6_STATE(da->iface);
+		TAILQ_FOREACH(dda, &state->addrs, next) {
+			if (IN6_ARE_ADDR_EQUAL(&dda->addr, &da->addr))
+				break;
+		}
+		if (dda != NULL) {
+			TAILQ_REMOVE(&state->addrs, dda, next);
+			ipv6_freeaddr(dda);
+		}
+	}
+}
+#endif
+
 static void
 dhcp6_deprecateaddrs(struct ipv6_addrhead *addrs)
 {
 	struct ipv6_addr *ia, *ian;
+	struct timespec now;
 
+	timespecclear(&now);
 	TAILQ_FOREACH_SAFE(ia, addrs, next, ian) {
 		if (ia->flags & IPV6_AF_EXTENDED)
 			;
@@ -2373,24 +2415,8 @@ dhcp6_deprecateaddrs(struct ipv6_addrhead *addrs)
 #ifndef SMALL
 		/* If we delegated from this prefix, deprecate or remove
 		 * the delegations. */
-		if (ia->flags & IPV6_AF_DELEGATEDPFX) {
-			struct ipv6_addr *da;
-			bool touched = false;
-
-			TAILQ_FOREACH(da, &ia->pd_pfxs, pd_next) {
-				if (ia->prefix_vltime == 0) {
-					if (da->prefix_vltime != 0) {
-						da->prefix_vltime = 0;
-						touched = true;
-					}
-				} else if (da->prefix_pltime != 0) {
-					da->prefix_pltime = 0;
-					touched = true;
-				}
-			}
-			if (touched)
-				ipv6_addaddrs(&ia->pd_pfxs);
-		}
+		if (ia->flags & IPV6_AF_DELEGATEDPFX)
+			dhcp6_deprecatedele(ia);
 #endif
 
 		if (ia->flags & IPV6_AF_REQUEST) {
diff --git a/src/ipv6.c b/src/ipv6.c
index d3dfe064..347cb303 100644
--- a/src/ipv6.c
+++ b/src/ipv6.c
@@ -898,52 +898,54 @@ ipv6_findaddr(struct dhcpcd_ctx *ctx, const struct in6_addr *addr, unsigned int
 #endif
 }
 
+int
+ipv6_doaddr(struct ipv6_addr *ia, struct timespec *now)
+{
+
+	/* A delegated prefix is not an address. */
+	if (ia->flags & IPV6_AF_DELEGATEDPFX)
+		return 0;
+
+	if (ia->prefix_vltime == 0) {
+		if (ia->flags & IPV6_AF_ADDED)
+			ipv6_deleteaddr(ia);
+		eloop_q_timeout_delete(ia->iface->ctx->eloop,
+		    0, NULL, ia);
+		if (ia->flags & IPV6_AF_REQUEST) {
+			ia->flags &= ~IPV6_AF_ADDED;
+			return 0;
+		}
+		return -1;
+	}
+
+	if (ia->flags & IPV6_AF_STALE ||
+	    IN6_IS_ADDR_UNSPECIFIED(&ia->addr))
+		return 0;
+
+	if (!timespecisset(now))
+		clock_gettime(CLOCK_MONOTONIC, now);
+	ipv6_addaddr(ia, now);
+	return ia->flags & IPV6_AF_NEW ? 1 : 0;
+}
+
 ssize_t
-ipv6_addaddrs(struct ipv6_addrhead *addrs)
+ipv6_addaddrs(struct ipv6_addrhead *iaddrs)
 {
-	struct ipv6_addr *ap, *apn;
-	ssize_t i;
 	struct timespec now;
+	struct ipv6_addr *ia, *ian;
+	ssize_t i, r;
 
 	i = 0;
 	timespecclear(&now);
-	TAILQ_FOREACH_SAFE(ap, addrs, next, apn) {
-		/* A delegated prefix is not an address. */
-		if (ap->flags & IPV6_AF_DELEGATEDPFX)
-			continue;
-		if (ap->prefix_vltime == 0) {
-			if (ap->flags & IPV6_AF_ADDED) {
-				ipv6_deleteaddr(ap);
-				i++;
-			}
-			eloop_q_timeout_delete(ap->iface->ctx->eloop,
-			    0, NULL, ap);
-			if (ap->flags & IPV6_AF_REQUEST) {
-				ap->flags &= ~IPV6_AF_ADDED;
-			} else {
-#ifndef SMALL
-				if (ap->delegating_prefix != NULL &&
-				    addrs == &ap->delegating_prefix->pd_pfxs) {
-					TAILQ_REMOVE(addrs, ap, pd_next);
-					ap->delegating_prefix = NULL;
-				} else
-#endif
-				{
-					TAILQ_REMOVE(addrs, ap, next);
-					ipv6_freeaddr(ap);
-				}
-			}
-		} else if (!(ap->flags & IPV6_AF_STALE) &&
-		    !IN6_IS_ADDR_UNSPECIFIED(&ap->addr))
-		{
-			if (ap->flags & IPV6_AF_NEW)
-				i++;
-			if (!timespecisset(&now))
-				clock_gettime(CLOCK_MONOTONIC, &now);
-			ipv6_addaddr(ap, &now);
+	TAILQ_FOREACH_SAFE(ia, iaddrs, next, ian) {
+		r = ipv6_doaddr(ia, &now);
+		if (r != 0)
+			i++;
+		if (r == -1) {
+			TAILQ_REMOVE(iaddrs, ia, next);
+			ipv6_freeaddr(ia);
 		}
 	}
-
 	return i;
 }
 
diff --git a/src/ipv6.h b/src/ipv6.h
index cc3e8a67..49c36765 100644
--- a/src/ipv6.h
+++ b/src/ipv6.h
@@ -247,6 +247,7 @@ void ipv6_checkaddrflags(void *);
 void ipv6_markaddrsstale(struct interface *, unsigned int);
 void ipv6_deletestaleaddrs(struct interface *);
 int ipv6_addaddr(struct ipv6_addr *, const struct timespec *);
+int ipv6_doaddr(struct ipv6_addr *, struct timespec *);
 ssize_t ipv6_addaddrs(struct ipv6_addrhead *addrs);
 void ipv6_deleteaddr(struct ipv6_addr *);
 void ipv6_freedrop_addrs(struct ipv6_addrhead *, int,