Change data structures and related functions to hold source prefixes.

babeld.c

@@ -714,7 +714,7 @@ main(int argc, char **argv)
             if(timeval_compare(&now, &ifp->hello_timeout) >= 0)
                 send_hello(ifp);
             if(timeval_compare(&now, &ifp->update_timeout) >= 0)
-                send_update(ifp, 0, NULL, 0);
+                send_update(ifp, 0, NULL, 0, NULL, 0);
             if(timeval_compare(&now, &ifp->update_flush_timeout) >= 0)
                 flushupdates(ifp);
         }

configuration.c

@@ -938,6 +938,7 @@ do_filter(struct filter *f, const unsigned char *id,
 int
 input_filter(const unsigned char *id,
              const unsigned char *prefix, unsigned short plen,
+             const unsigned char *src_prefix, unsigned short src_plen,
              const unsigned char *neigh, unsigned int ifindex)
 {
     int res;
@@ -948,8 +949,10 @@ input_filter(const unsigned char *id,
 }
 
 int
-output_filter(const unsigned char *id, const unsigned char *prefix,
-              unsigned short plen, unsigned int ifindex)
+output_filter(const unsigned char *id,
+              const unsigned char *prefix, unsigned short plen,
+              const unsigned char *src_prefix, unsigned short src_plen,
+              unsigned int ifindex)
 {
     int res;
     res = do_filter(output_filters, id, prefix, plen, NULL, ifindex, 0);
@@ -960,6 +963,7 @@ output_filter(const unsigned char *id, const unsigned char *prefix,
 
 int
 redistribute_filter(const unsigned char *prefix, unsigned short plen,
+                    const unsigned char *src_prefix, unsigned short src_plen,
                     unsigned int ifindex, int proto)
 {
     int res;

configuration.h

@@ -42,9 +42,13 @@ void renumber_filters(void);
 
 int input_filter(const unsigned char *id,
                  const unsigned char *prefix, unsigned short plen,
+                 const unsigned char *src_prefix, unsigned short src_plen,
                  const unsigned char *neigh, unsigned int ifindex);
-int output_filter(const unsigned char *id, const unsigned char *prefix,
-                  unsigned short plen, unsigned int ifindex);
+int output_filter(const unsigned char *id,
+                  const unsigned char *prefix, unsigned short plen,
+                  const unsigned char *src_prefix, unsigned short src_plen,
+                  unsigned int ifindex);
 int redistribute_filter(const unsigned char *prefix, unsigned short plen,
+                    const unsigned char *src_prefix, unsigned short src_plen,
                     unsigned int ifindex, int proto);
 int finalise_config(void);

interface.c

@@ -380,7 +380,7 @@ interface_up(struct interface *ifp, int up)
         set_timeout(&ifp->update_timeout, ifp->update_interval);
         send_hello(ifp);
         if(rc > 0)
-            send_update(ifp, 0, NULL, 0);
+            send_update(ifp, 0, NULL, 0, NULL, 0);
         send_request(ifp, NULL, 0);
     } else {
         flush_interface_routes(ifp, 0);
@@ -467,7 +467,7 @@ check_interfaces(void)
             rc = check_interface_ipv4(ifp);
             if(rc > 0) {
                 send_request(ifp, NULL, 0);
-                send_update(ifp, 0, NULL, 0);
+                send_update(ifp, 0, NULL, 0, NULL, 0);
             }
         }
     }

message.c

@@ -541,7 +541,7 @@ parse_packet(const unsigned char *from, struct interface *ifp,
                                         len - parsed_len, channels);
             }
 
-            update_route(router_id, prefix, plen, seqno, metric, interval,
+            update_route(router_id, prefix, plen, NULL, 0, seqno, metric, interval,
                          neigh, nh,
                          channels, channels_len(channels));
         } else if(type == MESSAGE_REQUEST) {
@@ -565,9 +565,9 @@ parse_packet(const unsigned char *from, struct interface *ifp,
                    shortly after we sent a full update. */
                 if(neigh->ifp->last_update_time <
                    now.tv_sec - MAX(neigh->ifp->hello_interval / 100, 1))
-                    send_update(neigh->ifp, 0, NULL, 0);
+                    send_update(neigh->ifp, 0, NULL, 0, zeroes, 0);
             } else {
-                send_update(neigh->ifp, 0, prefix, plen);
+                send_update(neigh->ifp, 0, prefix, plen, zeroes, 0);
             }
         } else if(type == MESSAGE_MH_REQUEST) {
             unsigned char prefix[16], plen;
@@ -1002,7 +1002,8 @@ really_send_update(struct interface *ifp,
     if(!if_up(ifp))
         return;
 
-    add_metric = output_filter(id, prefix, plen, ifp->ifindex);
+    add_metric = output_filter(id, prefix, plen, zeroes,
+                               0, ifp->ifindex);
     if(add_metric >= INFINITY)
         return;
 
@@ -1146,7 +1147,7 @@ flushupdates(struct interface *ifp)
            with the same router-id together, with IPv6 going out before IPv4. */
 
         for(i = 0; i < n; i++) {
-            route = find_installed_route(b[i].prefix, b[i].plen);
+            route = find_installed_route(b[i].prefix, b[i].plen, zeroes, 0);
             if(route)
                 memcpy(b[i].id, route->src->id, 8);
             else
@@ -1166,8 +1167,10 @@ flushupdates(struct interface *ifp)
                     continue;
             }
 
-            xroute = find_xroute(b[i].prefix, b[i].plen);
-            route = find_installed_route(b[i].prefix, b[i].plen);
+            xroute = find_xroute(b[i].prefix, b[i].plen,
+                                 zeroes, 0);
+            route = find_installed_route(b[i].prefix, b[i].plen,
+                                         zeroes, 0);
 
             if(xroute && (!route || xroute->metric <= kernel_metric)) {
                 really_send_update(ifp, myid,
@@ -1191,6 +1194,8 @@ flushupdates(struct interface *ifp)
 
                 if(metric < INFINITY)
                     satisfy_request(route->src->prefix, route->src->plen,
+                                    route->src->src_prefix,
+                                    route->src->src_plen,
                                     seqno, route->src->id, ifp);
 
                 if((ifp->flags & IF_SPLIT_HORIZON) &&
@@ -1284,20 +1289,21 @@ buffer_update(struct interface *ifp,
 
 void
 send_update(struct interface *ifp, int urgent,
-            const unsigned char *prefix, unsigned char plen)
+            const unsigned char *prefix, unsigned char plen,
+            const unsigned char *src_prefix, unsigned char src_plen)
 {
     if(ifp == NULL) {
         struct interface *ifp_aux;
         struct babel_route *route;
         FOR_ALL_INTERFACES(ifp_aux)
-            send_update(ifp_aux, urgent, prefix, plen);
+            send_update(ifp_aux, urgent, prefix, plen, src_prefix, src_plen);
         if(prefix) {
             /* Since flushupdates only deals with non-wildcard interfaces, we
                need to do this now. */
-            route = find_installed_route(prefix, plen);
+            route = find_installed_route(prefix, plen, src_prefix, src_plen);
             if(route && route_metric(route) < INFINITY)
-                satisfy_request(prefix, plen, route->src->seqno, route->src->id,
-                                NULL);
+                satisfy_request(prefix, plen, src_prefix, src_plen,
+                                route->src->seqno, route->src->id, NULL);
         }
         return;
     }
@@ -1333,12 +1339,14 @@ send_update(struct interface *ifp, int urgent,
 
 void
 send_update_resend(struct interface *ifp,
-                   const unsigned char *prefix, unsigned char plen)
+                   const unsigned char *prefix, unsigned char plen,
+                   const unsigned char *src_prefix, unsigned char src_plen)
 {
     assert(prefix != NULL);
 
-    send_update(ifp, 1, prefix, plen);
-    record_resend(RESEND_UPDATE, prefix, plen, 0, NULL, NULL, resend_delay);
+    send_update(ifp, 1, prefix, plen, src_prefix, src_plen);
+    record_resend(RESEND_UPDATE, prefix, plen, src_prefix, src_plen,
+                  0, NULL, NULL, resend_delay);
 }
 
 void
@@ -1394,7 +1402,8 @@ send_self_update(struct interface *ifp)
         while(1) {
             struct xroute *xroute = xroute_stream_next(xroutes);
             if(xroute == NULL) break;
-            send_update(ifp, 0, xroute->prefix, xroute->plen);
+            send_update(ifp, 0, xroute->prefix, xroute->plen,
+                        xroute->src_prefix, xroute->src_plen);
         }
         xroute_stream_done(xroutes);
     } else {
@@ -1678,7 +1687,7 @@ send_request_resend(struct neighbour *neigh,
     else
         send_multihop_request(NULL, prefix, plen, seqno, id, 127);
 
-    record_resend(RESEND_REQUEST, prefix, plen, seqno, id,
+    record_resend(RESEND_REQUEST, prefix, plen, zeroes, 0, seqno, id,
                   neigh ? neigh->ifp : NULL, resend_delay);
 }
 
@@ -1691,8 +1700,8 @@ handle_request(struct neighbour *neigh, const unsigned char *prefix,
     struct babel_route *route;
     struct neighbour *successor = NULL;
 
-    xroute = find_xroute(prefix, plen);
-    route = find_installed_route(prefix, plen);
+    xroute = find_xroute(prefix, plen, zeroes, 0);
+    route = find_installed_route(prefix, plen, zeroes, 0);
 
     if(xroute && (!route || xroute->metric <= kernel_metric)) {
         if(hop_count > 0 && memcmp(id, myid, 8) == 0) {
@@ -1704,14 +1713,16 @@ handle_request(struct neighbour *neigh, const unsigned char *prefix,
                 update_myseqno();
             }
         }
-        send_update(neigh->ifp, 1, prefix, plen);
+        send_update(neigh->ifp, 1, prefix, plen,
+                    xroute->src_prefix, xroute->src_plen);
         return;
     }
 
     if(route &&
        (memcmp(id, route->src->id, 8) != 0 ||
         seqno_compare(seqno, route->seqno) <= 0)) {
-        send_update(neigh->ifp, 1, prefix, plen);
+        send_update(neigh->ifp, 1, prefix, plen,
+                    route->src->src_prefix, route->src->src_plen);
         return;
     }
 
@@ -1736,7 +1747,8 @@ handle_request(struct neighbour *neigh, const unsigned char *prefix,
            find a different neighbour to forward the request to. */
         struct babel_route *other_route;
 
-        other_route = find_best_route(prefix, plen, 0, neigh);
+        other_route = find_best_route(prefix, plen, zeroes, 0,
+                                      0, neigh);
         if(other_route && route_metric(other_route) < INFINITY)
             successor = other_route->neigh;
     }
@@ -1747,6 +1759,6 @@ handle_request(struct neighbour *neigh, const unsigned char *prefix,
 
     send_unicast_multihop_request(successor, prefix, plen, seqno, id,
                                   hop_count - 1);
-    record_resend(RESEND_REQUEST, prefix, plen, seqno, id,
+    record_resend(RESEND_REQUEST, prefix, plen, zeroes, 0, seqno, id,
                   neigh->ifp, 0);
 }

message.h

@@ -67,9 +67,12 @@ void send_hello_noupdate(struct interface *ifp, unsigned interval);
 void send_hello(struct interface *ifp);
 void flush_unicast(int dofree);
 void send_update(struct interface *ifp, int urgent,
-                 const unsigned char *prefix, unsigned char plen);
+                 const unsigned char *prefix, unsigned char plen,
+                 const unsigned char *src_prefix, unsigned char src_plen);
 void send_update_resend(struct interface *ifp,
-                        const unsigned char *prefix, unsigned char plen);
+                        const unsigned char *prefix, unsigned char plen,
+                        const unsigned char *src_prefix,
+                        unsigned char src_plen);
 void send_wildcard_retraction(struct interface *ifp);
 void update_myseqno(void);
 void send_self_update(struct interface *ifp);

resend.c

@@ -75,6 +75,7 @@ find_resend(int kind, const unsigned char *prefix, unsigned char plen,
 
 struct resend *
 find_request(const unsigned char *prefix, unsigned char plen,
+             const unsigned char *src_prefix, unsigned char src_plen,
              struct resend **previous_return)
 {
     return find_resend(RESEND_REQUEST, prefix, plen, previous_return);
@@ -82,6 +83,7 @@ find_request(const unsigned char *prefix, unsigned char plen,
 
 int
 record_resend(int kind, const unsigned char *prefix, unsigned char plen,
+              const unsigned char *src_prefix, unsigned char src_plen,
               unsigned short seqno, const unsigned char *id,
               struct interface *ifp, int delay)
 {
@@ -89,9 +91,11 @@ record_resend(int kind, const unsigned char *prefix, unsigned char plen,
     unsigned int ifindex = ifp ? ifp->ifindex : 0;
 
     if((kind == RESEND_REQUEST &&
-        input_filter(NULL, prefix, plen, NULL, ifindex) >= INFINITY) ||
+        input_filter(NULL, prefix, plen, NULL, 0, NULL, ifindex) >=
+        INFINITY) ||
        (kind == RESEND_UPDATE &&
-        output_filter(NULL, prefix, plen, ifindex) >= INFINITY))
+        output_filter(NULL, prefix, plen, src_prefix, src_plen, ifindex) >=
+        INFINITY))
         return 0;
 
     if(delay >= 0xFFFF)
@@ -161,7 +165,7 @@ unsatisfied_request(const unsigned char *prefix, unsigned char plen,
 {
     struct resend *request;
 
-    request = find_request(prefix, plen, NULL);
+    request = find_request(prefix, plen, zeroes, 0, NULL);
     if(request == NULL || resend_expired(request))
         return 0;
 
@@ -180,7 +184,7 @@ request_redundant(struct interface *ifp,
 {
     struct resend *request;
 
-    request = find_request(prefix, plen, NULL);
+    request = find_request(prefix, plen, zeroes, 0, NULL);
     if(request == NULL || resend_expired(request))
         return 0;
 
@@ -205,12 +209,13 @@ request_redundant(struct interface *ifp,
 
 int
 satisfy_request(const unsigned char *prefix, unsigned char plen,
+                const unsigned char *src_prefix, unsigned char src_plen,
                 unsigned short seqno, const unsigned char *id,
                 struct interface *ifp)
 {
     struct resend *request, *previous;
 
-    request = find_request(prefix, plen, &previous);
+    request = find_request(prefix, plen, zeroes, 0, &previous);
     if(request == NULL)
         return 0;
 
@@ -297,7 +302,8 @@ do_resend()
                     break;
                 case RESEND_UPDATE:
                     send_update(resend->ifp, 1,
-                                resend->prefix, resend->plen);
+                                resend->prefix, resend->plen,
+                                zeroes, 0);
                     break;
                 default: abort();
                 }

resend.h

@@ -42,9 +42,11 @@ struct resend {
 extern struct timeval resend_time;
 
 struct resend *find_request(const unsigned char *prefix, unsigned char plen,
+                    const unsigned char *src_prefix, unsigned char src_plen,
                     struct resend **previous_return);
 void flush_resends(struct neighbour *neigh);
 int record_resend(int kind, const unsigned char *prefix, unsigned char plen,
+                  const unsigned char *src_prefix, unsigned char src_plen,
                   unsigned short seqno, const unsigned char *id,
                   struct interface *ifp, int delay);
 int unsatisfied_request(const unsigned char *prefix, unsigned char plen,
@@ -53,6 +55,7 @@ int request_redundant(struct interface *ifp,
                       const unsigned char *prefix, unsigned char plen,
                       unsigned short seqno, const unsigned char *id);
 int satisfy_request(const unsigned char *prefix, unsigned char plen,
+                    const unsigned char *src_prefix, unsigned char src_plen,
                     unsigned short seqno, const unsigned char *id,
                     struct interface *ifp);
 

route.c

@@ -57,6 +57,7 @@ static int two_to_the_one_over_hl = 0; /* 2^(1/hl) * 0x10000 */
 
 static int
 route_compare(const unsigned char *prefix, unsigned char plen,
+              const unsigned char *src_prefix, unsigned char src_plen,
               struct babel_route *route)
 {
     int i = memcmp(prefix, route->src->prefix, 16);
@@ -65,9 +66,22 @@ route_compare(const unsigned char *prefix, unsigned char plen,
 
     if(plen < route->src->plen)
         return -1;
-    else if(plen > route->src->plen)
+    if(plen > route->src->plen)
         return 1;
-    else
+
+    if(src_plen == 0) {
+        if(route->src->src_plen > 0)
+            return -1;
+    } else {
+        i = memcmp(src_prefix, route->src->src_prefix, 16);
+        if(i != 0)
+            return i;
+        if(src_plen < route->src->src_plen)
+            return -1;
+        if(src_plen > route->src->src_plen)
+            return 1;
+    }
+
     return 0;
 }
 
@@ -76,6 +90,7 @@ route_compare(const unsigned char *prefix, unsigned char plen,
 
 static int
 find_route_slot(const unsigned char *prefix, unsigned char plen,
+                const unsigned char *src_prefix, unsigned char src_plen,
                 int *new_return)
 {
     int p, m, g, c;
@@ -90,7 +105,7 @@ find_route_slot(const unsigned char *prefix, unsigned char plen,
 
     do {
         m = (p + g) / 2;
-        c = route_compare(prefix, plen, routes[m]);
+        c = route_compare(prefix, plen, src_prefix, src_plen, routes[m]);
         if(c == 0)
             return m;
         else if(c < 0)
@@ -107,10 +122,11 @@ find_route_slot(const unsigned char *prefix, unsigned char plen,
 
 struct babel_route *
 find_route(const unsigned char *prefix, unsigned char plen,
+           const unsigned char *src_prefix, unsigned char src_plen,
            struct neighbour *neigh, const unsigned char *nexthop)
 {
     struct babel_route *route;
-    int i = find_route_slot(prefix, plen, NULL);
+    int i = find_route_slot(prefix, plen, src_prefix, src_plen, NULL);
 
     if(i < 0)
         return NULL;
@@ -127,9 +143,10 @@ find_route(const unsigned char *prefix, unsigned char plen,
 }
 
 struct babel_route *
-find_installed_route(const unsigned char *prefix, unsigned char plen)
+find_installed_route(const unsigned char *prefix, unsigned char plen,
+                     const unsigned char *src_prefix, unsigned char src_plen)
 {
-    int i = find_route_slot(prefix, plen, NULL);
+    int i = find_route_slot(prefix, plen, src_prefix, src_plen, NULL);
 
     if(i >= 0 && routes[i]->installed)
         return routes[i];
@@ -173,7 +190,8 @@ insert_route(struct babel_route *route)
 
     assert(!route->installed);
 
-    i = find_route_slot(route->src->prefix, route->src->plen, &n);
+    i = find_route_slot(route->src->prefix, route->src->plen,
+                        route->src->src_prefix, route->src->src_plen, &n);
 
     if(i < 0) {
         if(route_slots >= max_route_slots)
@@ -214,7 +232,8 @@ flush_route(struct babel_route *route)
         lost = 1;
     }
 
-    i = find_route_slot(route->src->prefix, route->src->plen, NULL);
+    i = find_route_slot(route->src->prefix, route->src->plen,
+                        route->src->src_prefix, route->src->src_plen, NULL);
     assert(i >= 0 && i < route_slots);
 
     local_notify_route(route, LOCAL_FLUSH);
@@ -406,7 +425,8 @@ install_route(struct babel_route *route)
         fprintf(stderr, "WARNING: installing unfeasible route "
                 "(this shouldn't happen).");
 
-    i = find_route_slot(route->src->prefix, route->src->plen, NULL);
+    i = find_route_slot(route->src->prefix, route->src->plen,
+                        route->src->src_prefix, route->src->src_plen, NULL);
     assert(i >= 0 && i < route_slots);
 
     if(routes[i] != route && routes[i]->installed) {
@@ -416,7 +436,7 @@ install_route(struct babel_route *route)
     }
 
     rc = kernel_route(ROUTE_ADD, route->src->prefix, route->src->plen,
-                      zeroes, 0,
+                      route->src->src_prefix, route->src->src_plen,
                       route->nexthop,
                       route->neigh->ifp->ifindex,
                       metric_to_kernel(route_metric(route)), NULL, 0, 0);
@@ -441,7 +461,7 @@ uninstall_route(struct babel_route *route)
         return;
 
     rc = kernel_route(ROUTE_FLUSH, route->src->prefix, route->src->plen,
-                      zeroes, 0,
+                      route->src->src_prefix, route->src->src_plen,
                       route->nexthop,
                       route->neigh->ifp->ifindex,
                       metric_to_kernel(route_metric(route)), NULL, 0, 0);
@@ -474,11 +494,14 @@ switch_routes(struct babel_route *old, struct babel_route *new)
                 "(this shouldn't happen).");
 
     rc = kernel_route(ROUTE_MODIFY, old->src->prefix, old->src->plen,
-                      zeroes, 0,
+                      old->src->src_prefix, old->src->src_plen,
                       old->nexthop, old->neigh->ifp->ifindex,
                       metric_to_kernel(route_metric(old)),
                       new->nexthop, new->neigh->ifp->ifindex,
                       metric_to_kernel(route_metric(new)));
+    /* XXX : should the source-ip be subject to changes ? */
+    assert(memcmp(old->src->src_prefix, new->src->src_prefix, 16) == 0
+           && old->src->src_plen == new->src->src_plen);
     if(rc < 0) {
         perror("kernel_route(MODIFY)");
         return;
@@ -487,6 +510,8 @@ switch_routes(struct babel_route *old, struct babel_route *new)
     old->installed = 0;
     new->installed = 1;
     move_installed_route(new, find_route_slot(new->src->prefix, new->src->plen,
+                                              new->src->src_prefix,
+                                              new->src->src_plen,
                                               NULL));
     local_notify_route(old, LOCAL_CHANGE);
     local_notify_route(new, LOCAL_CHANGE);
@@ -505,7 +530,7 @@ change_route_metric(struct babel_route *route,
     if(route->installed && old != new) {
         int rc;
         rc = kernel_route(ROUTE_MODIFY, route->src->prefix, route->src->plen,
-                          zeroes, 0,
+                          route->src->src_prefix, route->src->src_plen,
                           route->nexthop, route->neigh->ifp->ifindex,
                           old,
                           route->nexthop, route->neigh->ifp->ifindex,
@@ -694,11 +719,12 @@ route_acceptable(struct babel_route *route, int feasible,
    that's probably overkill. */
 
 struct babel_route *
-find_best_route(const unsigned char *prefix, unsigned char plen, int feasible,
-                struct neighbour *exclude)
+find_best_route(const unsigned char *prefix, unsigned char plen,
+                const unsigned char *src_prefix, unsigned char src_plen,
+                int feasible, struct neighbour *exclude)
 {
     struct babel_route *route, *r;
-    int i = find_route_slot(prefix, plen, NULL);
+    int i = find_route_slot(prefix, plen, src_prefix, src_plen, NULL);
 
     if(i < 0)
         return NULL;
@@ -738,6 +764,8 @@ update_route_metric(struct babel_route *route)
         struct neighbour *neigh = route->neigh;
         int add_metric = input_filter(route->src->id,
                                       route->src->prefix, route->src->plen,
+                                      route->src->src_prefix,
+                                      route->src->src_plen,
                                       neigh->address,
                                       neigh->ifp->ifindex);
         change_route_metric(route, route->refmetric,
@@ -789,6 +817,7 @@ update_interface_metric(struct interface *ifp)
 struct babel_route *
 update_route(const unsigned char *id,
              const unsigned char *prefix, unsigned char plen,
+             const unsigned char *src_prefix, unsigned char src_plen,
              unsigned short seqno, unsigned short refmetric,
              unsigned short interval,
              struct neighbour *neigh, const unsigned char *nexthop,
@@ -810,17 +839,18 @@ update_route(const unsigned char *id,
     }
 
     add_metric = input_filter(id, prefix, plen,
+                              src_prefix, src_plen,
                               neigh->address, neigh->ifp->ifindex);
     if(add_metric >= INFINITY)
         return NULL;
 
-    route = find_route(prefix, plen, neigh, nexthop);
+    route = find_route(prefix, plen, src_prefix, src_plen, neigh, nexthop);
 
     if(route && memcmp(route->src->id, id, 8) == 0)
         /* Avoid scanning the source table. */
         src = route->src;
     else
-        src = find_source(id, prefix, plen, 1, seqno);
+        src = find_source(id, prefix, plen, src_prefix, src_plen, 1, seqno);
 
     if(src == NULL)
         return NULL;
@@ -929,7 +959,9 @@ send_unfeasible_request(struct neighbour *neigh, int force,
                         unsigned short seqno, unsigned short metric,
                         struct source *src)
 {
-    struct babel_route *route = find_installed_route(src->prefix, src->plen);
+    struct babel_route *route = find_installed_route(src->prefix, src->plen,
+                                                     src->src_prefix,
+                                                     src->src_plen);
 
     if(seqno_minus(src->seqno, seqno) > 100) {
         /* Probably a source that lost its seqno.  Let it time-out. */
@@ -962,11 +994,14 @@ consider_route(struct babel_route *route)
     if(!route_feasible(route))
         return;
 
-    xroute = find_xroute(route->src->prefix, route->src->plen);
+    xroute = find_xroute(route->src->prefix, route->src->plen,
+                         route->src->src_prefix, route->src->src_plen);
     if(xroute && (allow_duplicates < 0 || xroute->metric >= allow_duplicates))
         return;
 
-    installed = find_installed_route(route->src->prefix, route->src->plen);
+    installed = find_installed_route(route->src->prefix, route->src->plen,
+                                     route->src->src_prefix,
+                                     route->src->src_plen);
 
     if(installed == NULL)
         goto install;
@@ -988,7 +1023,8 @@ consider_route(struct babel_route *route)
     if(installed && route->installed)
         send_triggered_update(route, installed->src, route_metric(installed));
     else
-        send_update(NULL, 1, route->src->prefix, route->src->plen);
+        send_update(NULL, 1, route->src->prefix, route->src->plen,
+                    route->src->src_prefix, route->src->src_plen);
     return;
 }
 
@@ -1054,9 +1090,11 @@ send_triggered_update(struct babel_route *route, struct source *oldsrc,
         urgent = 0;
 
     if(urgent >= 2)
-        send_update_resend(NULL, route->src->prefix, route->src->plen);
+        send_update_resend(NULL, route->src->prefix, route->src->plen,
+                           route->src->src_prefix, route->src->src_plen);
     else
-        send_update(NULL, urgent, route->src->prefix, route->src->plen);
+        send_update(NULL, urgent, route->src->prefix, route->src->plen,
+                    route->src->src_prefix, route->src->src_plen);
 
     if(oldmetric < INFINITY) {
         if(newmetric >= oldmetric + 512) {
@@ -1081,7 +1119,9 @@ route_changed(struct babel_route *route,
         struct babel_route *better_route;
         /* Do this unconditionally -- microoptimisation is not worth it. */
         better_route =
-            find_best_route(route->src->prefix, route->src->plen, 1, NULL);
+            find_best_route(route->src->prefix, route->src->plen,
+                            route->src->src_prefix, route->src->src_plen,
+                            1, NULL);
         if(better_route && route_metric(better_route) < route_metric(route))
             consider_route(better_route);
     }
@@ -1101,12 +1141,14 @@ void
 route_lost(struct source *src, unsigned oldmetric)
 {
     struct babel_route *new_route;
-    new_route = find_best_route(src->prefix, src->plen, 1, NULL);
+    new_route = find_best_route(src->prefix, src->plen,
+                                src->src_prefix, src->src_plen, 1, NULL);
     if(new_route) {
         consider_route(new_route);
     } else if(oldmetric < INFINITY) {
         /* Avoid creating a blackhole. */
-        send_update_resend(NULL, src->prefix, src->plen);
+        send_update_resend(NULL, src->prefix, src->plen,
+                           src->src_prefix, src->src_plen);
         /* If the route was usable enough, try to get an alternate one.
            If it was not, we could be dealing with oscillations around
            the value of INFINITY. */

route.h

@@ -70,9 +70,15 @@ route_metric_noninterfering(const struct babel_route *route)
 }
 
 struct babel_route *find_route(const unsigned char *prefix, unsigned char plen,
+                        const unsigned char *src_prefix, unsigned char src_plen,
                         struct neighbour *neigh, const unsigned char *nexthop);
 struct babel_route *find_installed_route(const unsigned char *prefix,
-                                   unsigned char plen);
+                        unsigned char plen, const unsigned char *src_prefix,
+                        unsigned char src_plen);
+struct babel_route *find_min_iroute(const unsigned char *dst_prefix,
+                        unsigned char dst_plen,
+                        const unsigned char *src_prefix, unsigned char src_plen,
+                        int is_min_dst, int is_min_src, int exclusive_min);
 int installed_routes_estimate(void);
 void flush_route(struct babel_route *route);
 void flush_all_routes(void);
@@ -93,6 +99,8 @@ void change_smoothing_half_life(int half_life);
 int route_smoothed_metric(struct babel_route *route);
 struct babel_route *find_best_route(const unsigned char *prefix,
                                     unsigned char plen,
+                                    const unsigned char *src_prefix,
+                                    unsigned char src_plen,
                                     int feasible, struct neighbour *exclude);
 struct babel_route *install_best_route(const unsigned char prefix[16],
                                  unsigned char plen);
@@ -101,6 +109,8 @@ void update_interface_metric(struct interface *ifp);
 void update_route_metric(struct babel_route *route);
 struct babel_route *update_route(const unsigned char *id,
                            const unsigned char *prefix, unsigned char plen,
+                           const unsigned char *src_prefix,
+                           unsigned char src_plen,
                            unsigned short seqno, unsigned short refmetric,
                            unsigned short interval, struct neighbour *neigh,
                            const unsigned char *nexthop,

source.c

@@ -35,7 +35,9 @@ THE SOFTWARE.
 struct source *srcs = NULL;
 
 struct source*
-find_source(const unsigned char *id, const unsigned char *p, unsigned char plen,
+find_source(const unsigned char *id,
+            const unsigned char *prefix, unsigned char plen,
+            const unsigned char *src_prefix, unsigned char src_plen,
             int create, unsigned short seqno)
 {
     struct source *src;
@@ -49,7 +51,11 @@ find_source(const unsigned char *id, const unsigned char *p, unsigned char plen,
             continue;
         if(src->plen != plen)
             continue;
-        if(memcmp(src->prefix, p, 16) == 0)
+        if(src->src_plen != src_plen)
+            continue;
+        if(memcmp(src->prefix, prefix, 16) != 0)
+            continue;
+        if(memcmp(src->src_prefix, src_prefix, 16) == 0)
             return src;
     }
 
@@ -63,8 +69,10 @@ find_source(const unsigned char *id, const unsigned char *p, unsigned char plen,
     }
 
     memcpy(src->id, id, 8);
-    memcpy(src->prefix, p, 16);
+    memcpy(src->prefix, prefix, 16);
     src->plen = plen;
+    memcpy(src->src_prefix, src_prefix, 16);
+    src->src_plen = src_plen;
     src->seqno = seqno;
     src->metric = INFINITY;
     src->time = now.tv_sec;

source.h

@@ -27,6 +27,8 @@ struct source {
     unsigned char id[8];
     unsigned char prefix[16];
     unsigned char plen;
+    unsigned char src_prefix[16];
+    unsigned char src_plen;
     unsigned short seqno;
     unsigned short metric;
     unsigned short route_count;
@@ -34,8 +36,10 @@ struct source {
 };
 
 struct source *find_source(const unsigned char *id,
-                           const unsigned char *p,
+                           const unsigned char *prefix,
                            unsigned char plen,
+                           const unsigned char *src_prefix,
+                           unsigned char src_plen,
                            int create, unsigned short seqno);
 struct source *retain_source(struct source *src);
 void release_source(struct source *src);

util.h

@@ -111,6 +111,7 @@ int linklocal(const unsigned char *address) ATTRIBUTE ((pure));
 int v4mapped(const unsigned char *address) ATTRIBUTE ((pure));
 void v4tov6(unsigned char *dst, const unsigned char *src);
 int daemonise(void);
+int set_src_prefix(unsigned char *src_addr, unsigned char *src_plen);
 
 enum prefix_status {
     PST_DISJOINT      = 1 << 0,

xroute.c

@@ -43,12 +43,15 @@ static struct xroute *xroutes;
 static int numxroutes = 0, maxxroutes = 0;
 
 struct xroute *
-find_xroute(const unsigned char *prefix, unsigned char plen)
+find_xroute(const unsigned char *prefix, unsigned char plen,
+            const unsigned char *src_prefix, unsigned char src_plen)
 {
     int i;
     for(i = 0; i < numxroutes; i++) {
         if(xroutes[i].plen == plen &&
-           memcmp(xroutes[i].prefix, prefix, 16) == 0)
+           memcmp(xroutes[i].prefix, prefix, 16) == 0 &&
+           xroutes[i].src_plen == src_plen &&
+           memcmp(xroutes[i].src_prefix, src_prefix, 16) == 0)
             return &xroutes[i];
     }
     return NULL;
@@ -86,9 +89,10 @@ flush_xroute(struct xroute *xroute)
 
 int
 add_xroute(unsigned char prefix[16], unsigned char plen,
+           unsigned char src_prefix[16], unsigned char src_plen,
            unsigned short metric, unsigned int ifindex, int proto)
 {
-    struct xroute *xroute = find_xroute(prefix, plen);
+    struct xroute *xroute = find_xroute(prefix, plen, src_prefix, src_plen);
     if(xroute) {
         if(xroute->metric <= metric)
             return 0;
@@ -111,6 +115,8 @@ add_xroute(unsigned char prefix[16], unsigned char plen,
 
     memcpy(xroutes[numxroutes].prefix, prefix, 16);
     xroutes[numxroutes].plen = plen;
+    memcpy(xroutes[numxroutes].src_prefix, src_prefix, 16);
+    xroutes[numxroutes].src_plen = src_plen;
     xroutes[numxroutes].metric = metric;
     xroutes[numxroutes].ifindex = ifindex;
     xroutes[numxroutes].proto = proto;
@@ -200,6 +206,7 @@ check_xroutes(int send_updates)
     while(i < numxroutes) {
         export = 0;
         metric = redistribute_filter(xroutes[i].prefix, xroutes[i].plen,
+                                     xroutes[i].src_prefix, xroutes[i].src_plen,
                                      xroutes[i].ifindex, xroutes[i].proto);
         if(metric < INFINITY && metric == xroutes[i].metric) {
             for(j = 0; j < numroutes; j++) {
@@ -215,17 +222,20 @@ check_xroutes(int send_updates)
 
         if(!export) {
             unsigned char prefix[16], plen;
+            unsigned char src_prefix[16], src_plen;
             struct babel_route *route;
             memcpy(prefix, xroutes[i].prefix, 16);
             plen = xroutes[i].plen;
+            memcpy(src_prefix, xroutes[i].src_prefix, 16);
+            src_plen = xroutes[i].src_plen;
             flush_xroute(&xroutes[i]);
-            route = find_best_route(prefix, plen, 1, NULL);
+            route = find_best_route(prefix, plen, src_prefix, src_plen, 1,NULL);
             if(route)
                 install_route(route);
             /* send_update_resend only records the prefix, so the update
                will only be sent after we perform all of the changes. */
             if(send_updates)
-                send_update_resend(NULL, prefix, plen);
+                send_update_resend(NULL, prefix, plen, src_prefix, src_plen);
             change = 1;
         } else {
             i++;
@@ -238,13 +248,17 @@ check_xroutes(int send_updates)
         if(martian_prefix(routes[i].prefix, routes[i].plen))
             continue;
         metric = redistribute_filter(routes[i].prefix, routes[i].plen,
+                                     routes[i].src_prefix, routes[i].src_plen,
                                      routes[i].ifindex, routes[i].proto);
         if(metric < INFINITY) {
             rc = add_xroute(routes[i].prefix, routes[i].plen,
+                            routes[i].src_prefix, routes[i].src_plen,
                             metric, routes[i].ifindex, routes[i].proto);
             if(rc > 0) {
                 struct babel_route *route;
-                route = find_installed_route(routes[i].prefix, routes[i].plen);
+                route = find_installed_route(routes[i].prefix, routes[i].plen,
+                                             routes[i].src_prefix,
+                                             routes[i].src_plen);
                 if(route) {
                     if(allow_duplicates < 0 ||
                        routes[i].metric < allow_duplicates)
@@ -252,7 +266,8 @@ check_xroutes(int send_updates)
                 }
                 change = 1;
                 if(send_updates)
-                    send_update(NULL, 0, routes[i].prefix, routes[i].plen);
+                    send_update(NULL, 0, routes[i].prefix, routes[i].plen,
+                                routes[i].src_prefix, routes[i].src_plen);
             }
         }
     }

xroute.h

@@ -23,6 +23,8 @@ THE SOFTWARE.
 struct xroute {
     unsigned char prefix[16];
     unsigned char plen;
+    unsigned char src_prefix[16];
+    unsigned char src_plen;
     unsigned short metric;
     unsigned int ifindex;
     int proto;
@@ -30,9 +32,11 @@ struct xroute {
 
 struct xroute_stream;
 
-struct xroute *find_xroute(const unsigned char *prefix, unsigned char plen);
+struct xroute *find_xroute(const unsigned char *prefix, unsigned char plen,
+                const unsigned char *src_prefix, unsigned char src_plen);
 void flush_xroute(struct xroute *xroute);
 int add_xroute(unsigned char prefix[16], unsigned char plen,
+               unsigned char src_prefix[16], unsigned char src_plen,
                unsigned short metric, unsigned int ifindex, int proto);
 int xroutes_estimate(void);
 struct xroute_stream *xroute_stream();