If we only have IPv4LL addresses, add a default route to the link so that

we stand a chance at communicating with non IPv4LL addresses on the same link.

diff --git a/ipv4.c b/ipv4.c
index 809b603d6668c9147dc187d7b5cf07d2429341a0..462585cbf9f9f76b7c443d382ee954c55a470037 100644 (file)
--- a/ipv4.c
+++ b/ipv4.c
@@ -293,6 +293,11 @@ desc_route(const char *cmd, const struct rt *rt)
        else if (rt->net.s_addr == htonl(INADDR_BROADCAST))
                logger(ctx, LOG_INFO, "%s: %s host route to %s via %s",
                    ifname, cmd, addr, inet_ntoa(rt->gate));
+       else if (rt->dest.s_addr == htonl(INADDR_ANY) &&
+           rt->net.s_addr == htonl(INADDR_ANY) &&
+           rt->gate.s_addr == htonl(INADDR_ANY))
+               logger(ctx, LOG_INFO, "%s: %s default route",
+                   ifname, cmd);
        else if (rt->gate.s_addr == htonl(INADDR_ANY))
                logger(ctx, LOG_INFO, "%s: %s route to %s/%d",
                    ifname, cmd, addr, inet_ntocidr(rt->net));
@@ -648,13 +653,60 @@ add_router_host_route(struct rt_head *rt, const struct interface *ifp)
        return rt;
 }
 
+static int
+ipv4_doroute(struct rt *rt, struct rt_head *nrs)
+{
+       const struct dhcp_state *state;
+       struct rt *or;
+
+       state = D_CSTATE(rt->iface);
+#ifdef HAVE_ROUTE_METRIC
+       rt->metric = rt->iface->metric;
+#endif
+       rt->flags = state->added & STATE_FAKE;
+       /* Is this route already in our table? */
+       if ((find_route(nrs, rt, NULL)) != NULL)
+               return 0;
+       /* Do we already manage it? */
+       if ((or = find_route(rt->iface->ctx->ipv4_routes, rt, NULL))) {
+               if (state->added & STATE_FAKE)
+                       return 0;
+               if (or->flags & STATE_FAKE ||
+                   or->iface != rt->iface ||
+#ifdef HAVE_ROUTE_METRIC
+                   rt->metric != or->metric ||
+#endif
+                   rt->src.s_addr != or->src.s_addr ||
+                   rt->gate.s_addr != or->gate.s_addr)
+               {
+                       if (c_route(or, rt) != 0)
+                               return 0;
+               }
+               TAILQ_REMOVE(rt->iface->ctx->ipv4_routes, or, next);
+               free(or);
+       } else {
+               if (state->added & STATE_FAKE) {
+                       or = ipv4_findrt(rt->iface->ctx, rt, 1);
+                       if (or == NULL ||
+                           or->gate.s_addr != rt->gate.s_addr)
+                               return 0;
+               } else {
+                       if (n_route(rt) != 0)
+                               return 0;
+               }
+       }
+       rt->flags |= STATE_ADDED;
+       return 1;
+}
+
 void
 ipv4_buildroutes(struct dhcpcd_ctx *ctx)
 {
        struct rt_head *nrs, *dnr;
-       struct rt *or, *rt, *rtn;
+       struct rt *rt, *rtn;
        struct interface *ifp;
        const struct dhcp_state *state;
+       int has_default;
 
        /* We need to have the interfaces in the correct order to ensure
         * our routes are managed correctly. */
@@ -666,6 +718,7 @@ ipv4_buildroutes(struct dhcpcd_ctx *ctx)
        }
        TAILQ_INIT(nrs);
 
+       has_default = 0;
        TAILQ_FOREACH(ifp, ctx->ifaces, next) {
                state = D_CSTATE(ifp);
                if (state != NULL && state->new != NULL && state->added) {
@@ -697,48 +750,29 @@ ipv4_buildroutes(struct dhcpcd_ctx *ctx)
                        continue;
                TAILQ_FOREACH_SAFE(rt, dnr, next, rtn) {
                        rt->iface = ifp;
-#ifdef HAVE_ROUTE_METRIC
-                       rt->metric = ifp->metric;
-#endif
-                       rt->flags = state->added & STATE_FAKE;
-                       /* Is this route already in our table? */
-                       if ((find_route(nrs, rt, NULL)) != NULL)
-                               continue;
-                       /* Do we already manage it? */
-                       if ((or = find_route(ctx->ipv4_routes, rt, NULL))) {
-                               if (state->added & STATE_FAKE)
-                                       continue;
-                               if (or->flags & STATE_FAKE ||
-                                   or->iface != ifp ||
-#ifdef HAVE_ROUTE_METRIC
-                                   rt->metric != or->metric ||
-#endif
-                                   rt->src.s_addr != or->src.s_addr ||
-                                   rt->gate.s_addr != or->gate.s_addr)
-                               {
-                                       if (c_route(or, rt) != 0)
-                                               continue;
-                               }
-                               TAILQ_REMOVE(ctx->ipv4_routes, or, next);
-                               free(or);
-                       } else {
-                               if (state->added & STATE_FAKE) {
-                                       or = ipv4_findrt(ctx, rt, 1);
-                                       if (or == NULL ||
-                                           or->gate.s_addr != rt->gate.s_addr)
-                                               continue;
-                               } else {
-                                       if (n_route(rt) != 0)
-                                               continue;
-                               }
+                       if (ipv4_doroute(rt, nrs) == 1) {
+                               TAILQ_REMOVE(dnr, rt, next);
+                               TAILQ_INSERT_TAIL(nrs, rt, next);
+                               if (rt->dest.s_addr == INADDR_ANY)
+                                       has_default = 1;
                        }
-                       rt->flags |= STATE_ADDED;
-                       TAILQ_REMOVE(dnr, rt, next);
-                       TAILQ_INSERT_TAIL(nrs, rt, next);
                }
                ipv4_freeroutes(dnr);
        }
 
+       /* If we don't manage a default route, grab one without a
+        * gateway for any IPv4LL enabled interfaces. */
+       if (!has_default) {
+               TAILQ_FOREACH(ifp, ctx->ifaces, next) {
+                       if ((rt = ipv4ll_default_route(ifp)) != NULL) {
+                               if (ipv4_doroute(rt, nrs) == 1)
+                                       TAILQ_INSERT_TAIL(nrs, rt, next);
+                               else
+                                       free(rt);
+                       }
+               }
+       }
+
        /* Remove old routes we used to manage */
        if (ctx->ipv4_routes) {
                TAILQ_FOREACH(rt, ctx->ipv4_routes, next) {

diff --git a/ipv4ll.c b/ipv4ll.c
index 1c84fe51762d4211294c09ea4a51e4975b63fe4b..c119778fc9dff115428bead8cfb345f655a0c9c5 100644 (file)
--- a/ipv4ll.c
+++ b/ipv4ll.c
@@ -92,6 +92,29 @@ ipv4ll_subnet_route(const struct interface *ifp)
        return rt;
 }
 
+struct rt *
+ipv4ll_default_route(const struct interface *ifp)
+{
+       const struct ipv4ll_state *state;
+       struct rt *rt;
+
+       assert(ifp != NULL);
+       if ((state = IPV4LL_CSTATE(ifp)) == NULL ||
+           state->addr.s_addr == INADDR_ANY)
+               return NULL;
+
+       if ((rt = malloc(sizeof(*rt))) == NULL) {
+               logger(ifp->ctx, LOG_ERR, "%s: malloc: %m", __func__);
+               return NULL;
+       }
+       rt->iface = ifp;
+       rt->dest.s_addr = INADDR_ANY;
+       rt->net.s_addr = INADDR_ANY;
+       rt->gate.s_addr = INADDR_ANY;
+       rt->src = state->addr;
+       return rt;
+}
+
 ssize_t
 ipv4ll_env(char **env, const char *prefix, const struct interface *ifp)
 {

diff --git a/ipv4ll.h b/ipv4ll.h
index 32390216a00e8895274abad07a63162a91c22508..4820c1437848464adb7375970836f0d250b40769 100644 (file)
--- a/ipv4ll.h
+++ b/ipv4ll.h
@@ -56,6 +56,7 @@ struct ipv4ll_state {
        IN_LINKLOCAL(ntohl(IPV4LL_CSTATE((ifp))->addr.s_addr)))
 
 struct rt* ipv4ll_subnet_route(const struct interface *);
+struct rt* ipv4ll_default_route(const struct interface *);
 ssize_t ipv4ll_env(char **, const char *, const struct interface *);
 void ipv4ll_start(void *);
 void ipv4ll_claimed(void *);