ND: Improve stale detection for >1 router

diff --git a/src/ipv6nd.c b/src/ipv6nd.c
index 0089b2694ccb5f0748036c44a024f0cce308602e..ba4eb8ca59fe21901f128d4854941f8c33ea4b7b 100644 (file)
--- a/src/ipv6nd.c
+++ b/src/ipv6nd.c
@@ -1016,6 +1016,30 @@ try_script:
        }
 }
 
+static struct ipv6_addr *
+ipv6nd_findmarkstale(struct ra *rap, struct ipv6_addr *ia, bool mark)
+{
+       struct dhcpcd_ctx *ctx = ia->iface->ctx;
+       struct ra *rap2;
+       struct ipv6_addr *ia2;
+
+       TAILQ_FOREACH(rap2, ctx->ra_routers, next) {
+               if (rap2 == rap ||
+                   rap2->iface != rap->iface ||
+                   rap2->expired)
+                       continue;
+               TAILQ_FOREACH(ia2, &rap2->addrs, next) {
+                       if (!IN6_ARE_ADDR_EQUAL(&ia->prefix, &ia2->prefix))
+                               continue;
+                       if (!(ia2->flags & IPV6_AF_STALE))
+                               return ia2;
+                       if (mark)
+                               ia2->prefix_pltime = 0;
+               }
+       }
+       return NULL;
+}
+
 #ifndef DHCP6
 /* If DHCPv6 is compiled out, supply a shim to provide an error message
  * if IPv6RA requests DHCPv6. */
@@ -1044,9 +1068,9 @@ ipv6nd_handlera(struct dhcpcd_ctx *ctx,
        struct nd_opt_mtu mtu;
        struct nd_opt_rdnss rdnss;
        uint8_t *p;
-       struct ra *rap, *rap2;
+       struct ra *rap;
        struct in6_addr pi_prefix;
-       struct ipv6_addr *ia, *ia2;
+       struct ipv6_addr *ia;
        struct dhcp_opt *dho;
        bool new_rap, new_data, has_address;
        uint32_t old_lifetime;
@@ -1394,23 +1418,9 @@ ipv6nd_handlera(struct dhcpcd_ctx *ctx,
        TAILQ_FOREACH(ia, &rap->addrs, next) {
                if (!(ia->flags & IPV6_AF_STALE) || ia->prefix_pltime == 0)
                        continue;
-               TAILQ_FOREACH(rap2, ctx->ra_routers, next) {
-                       if (rap2->iface != rap->iface || rap2->expired)
-                               continue;
-                       /* Other routers may have zeroed the address so it
-                        * won't be stale for them. */
-                       TAILQ_FOREACH(ia2, &rap2->addrs, next) {
-                               if (IN6_ARE_ADDR_EQUAL(&ia->prefix,
-                                   &ia2->prefix) &&
-                                   ia->prefix_pltime != 0 &&
-                                   ia->prefix_vltime != 0)
-                                       break;
-                       }
-                       if (ia2 != NULL)
-                               break;
-               }
-               if (rap2 != NULL && ia2 != NULL)
+               if (ipv6nd_findmarkstale(rap, ia, false) != NULL)
                        continue;
+               ipv6nd_findmarkstale(rap, ia, true);
                logdebugx("%s: %s: became stale", ifp->name, ia->saddr);
                ia->prefix_pltime = 0;
        }