Merge branch 'ss-tables-merge'

Makefile

@@ -10,10 +10,12 @@ CFLAGS = $(CDEBUGFLAGS) $(DEFINES) $(EXTRA_DEFINES)
 LDLIBS = -lrt
 
 SRCS = babeld.c net.c kernel.c util.c interface.c source.c neighbour.c \
-       route.c xroute.c message.c resend.c configuration.c local.c
+       route.c xroute.c message.c resend.c configuration.c local.c \
+       disambiguation.c
 
 OBJS = babeld.o net.o kernel.o util.o interface.o source.o neighbour.o \
-       route.o xroute.o message.o resend.o configuration.o local.o
+       route.o xroute.o message.o resend.o configuration.o local.o \
+       disambiguation.o
 
 babeld: $(OBJS)
 	$(CC) $(CFLAGS) $(LDFLAGS) -o babeld $(OBJS) $(LDLIBS)

babeld.c

@@ -82,6 +82,7 @@ unsigned char protocol_group[16];
 int protocol_socket = -1;
 int kernel_socket = -1;
 static int kernel_routes_changed = 0;
+static int kernel_rules_changed = 0;
 static int kernel_link_changed = 0;
 static int kernel_addr_changed = 0;
 
@@ -512,6 +513,7 @@ main(int argc, char **argv)
         fprintf(stderr, "Warning: couldn't check exported routes.\n");
 
     kernel_routes_changed = 0;
+    kernel_rules_changed = 0;
     kernel_link_changed = 0;
     kernel_addr_changed = 0;
     kernel_dump_time = now.tv_sec + roughly(30);
@@ -540,7 +542,7 @@ main(int argc, char **argv)
         send_hello(ifp);
         send_wildcard_retraction(ifp);
         send_self_update(ifp);
-        send_request(ifp, NULL, 0);
+        send_request(ifp, NULL, 0, NULL, 0);
         flushupdates(ifp);
         flushbuf(ifp);
     }
@@ -673,11 +675,12 @@ main(int argc, char **argv)
         }
 
         if(kernel_routes_changed || kernel_addr_changed ||
-           now.tv_sec >= kernel_dump_time) {
+           kernel_rules_changed || now.tv_sec >= kernel_dump_time) {
             rc = check_xroutes(1);
             if(rc < 0)
                 fprintf(stderr, "Warning: couldn't check exported routes.\n");
-            kernel_routes_changed = kernel_addr_changed = 0;
+            kernel_routes_changed = kernel_rules_changed =
+                kernel_addr_changed = 0;
             if(kernel_socket >= 0)
                 kernel_dump_time = now.tv_sec + roughly(300);
             else
@@ -714,7 +717,7 @@ 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);
         }
@@ -1028,9 +1031,10 @@ dump_route(FILE *out, struct babel_route *route)
             channels[0] = '\0';
     }
 
-    fprintf(out, "%s metric %d (%d) refmetric %d id %s seqno %d%s age %d "
-            "via %s neigh %s%s%s%s\n",
+    fprintf(out, "%s from %s metric %d (%d) refmetric %d id %s "
+            "seqno %d%s age %d via %s neigh %s%s%s%s\n",
             format_prefix(route->src->prefix, route->src->plen),
+            format_prefix(route->src->src_prefix, route->src->src_plen),
             route_metric(route), route_smoothed_metric(route), route->refmetric,
             format_eui64(route->src->id),
             (int)route->seqno,
@@ -1047,8 +1051,9 @@ dump_route(FILE *out, struct babel_route *route)
 static void
 dump_xroute(FILE *out, struct xroute *xroute)
 {
-    fprintf(out, "%s metric %d (exported)\n",
+    fprintf(out, "%s from %s metric %d (exported)\n",
             format_prefix(xroute->prefix, xroute->plen),
+            format_prefix(xroute->src_prefix, xroute->src_plen),
             xroute->metric);
 }
 
@@ -1138,5 +1143,7 @@ kernel_routes_callback(int changed, void *closure)
         kernel_addr_changed = 1;
     if(changed & CHANGE_ROUTE)
         kernel_routes_changed = 1;
+    if(changed & CHANGE_RULE)
+        kernel_rules_changed = 1;
     return 1;
 }

babeld.h

@@ -80,6 +80,12 @@ THE SOFTWARE.
 #endif
 #endif
 
+#ifdef IPV6_SUBTREES
+#define has_ipv6_subtrees 1
+#else
+#define has_ipv6_subtrees 0
+#endif
+
 extern struct timeval now;
 extern int debug;
 extern time_t reboot_time;

babeld.man

@@ -260,6 +260,14 @@ This specifies the name of the file to which
 .B babeld
 writes out its process id, and is equivalent to the command-line option
 .BR \-I .
+.TP
+.BI first-table-number " table"
+This specifies the index of the first routing table to use for
+source-specific routes.  The default is 10.
+.TP
+.BI first-rule-priority " priority"
+This specifies smallest (highest) rule priority used with source-specific
+routes.  The default is 100.
 .SS Interface configuration
 An interface is configured by a line with the following format:
 .IP
@@ -410,6 +418,23 @@ This entry only applies to routes with a prefix length less or equal to
 This entry only applies to routes with a prefix length greater or equal to
 .BR plen .
 .TP
+.BI src-ip " prefix"
+This entry only applies to routes with a source prefix in the given prefix.
+.TP
+.BI src-eq " plen"
+This entry only applies to routes with a source prefix length equal to
+.BR plen .
+.TP
+.BI src-le " plen"
+This entry only applies to routes with a source prefix length less or
+equal to
+.BR plen .
+.TP
+.BI src-ge " plen"
+This entry only applies to routes with a source prefix length greater
+or equal to
+.BR plen .
+.TP
 .BI neigh " address"
 This entry only applies to routes learned from a neighbour with
 link-local address
@@ -454,6 +479,10 @@ For an input or output filter, allow this route after increasing its metric by
 .IR value .
 For a redistribute filter, redistribute this route with metric
 .IR value .
+.TP
+.BI src-prefix " prefix"
+For a redistribute filter, set the source prefix of this route to
+.IR prefix .
 .PP
 If
 .I action
@@ -496,6 +525,12 @@ or, if you want to constrain the routes that you redistribute,
     \-C 'redistribute proto 11 ip ::/0 le 64 metric 256' \\
     \-C 'redistribute proto 11 ip 0.0.0.0/0 le 24 metric 256' \\
     wlan0
+.SS Source-sensitive routing
+.PP
+If your want to redistribute kernel routes as source-specific to the network,
+with the 2001:DB8:0:1::/64 prefix:
+.IP
+redistribute src-prefix 2001:DB8:0:1::/64
 .SH FILES
 .TP
 .B /etc/babeld.conf

configuration.c

@@ -283,6 +283,7 @@ parse_filter(int c, gnc_t gnc, void *closure, struct filter **filter_return)
     if(filter == NULL)
         goto error;
     filter->plen_le = 128;
+    filter->src_plen_le = 128;
 
     while(1) {
         c = skip_whitespace(c, gnc, closure);
@@ -295,10 +296,25 @@ parse_filter(int c, gnc_t gnc, void *closure, struct filter **filter_return)
             goto error;
 
         if(strcmp(token, "ip") == 0) {
-            c = getnet(c, &filter->prefix, &filter->plen, &filter->af,
+            int af;
+            c = getnet(c, &filter->prefix, &filter->plen, &af,
                        gnc, closure);
             if(c < -1)
                 goto error;
+            if(filter->af == AF_UNSPEC)
+                filter->af = af;
+            else if(filter->af != af)
+                goto error;
+        } else if(strcmp(token, "src-ip") == 0) {
+            int af;
+            c = getnet(c, &filter->src_prefix, &filter->src_plen, &af,
+                       gnc, closure);
+            if(c < -1)
+                goto error;
+            if(filter->af == AF_UNSPEC)
+                filter->af = af;
+            else if(filter->af != af)
+                goto error;
         } else if(strcmp(token, "eq") == 0) {
             int p;
             c = getint(c, &p, gnc, closure);
@@ -318,6 +334,25 @@ parse_filter(int c, gnc_t gnc, void *closure, struct filter **filter_return)
             if(c < -1)
                 goto error;
             filter->plen_ge = MAX(filter->plen_ge, p);
+        } else if(strcmp(token, "src-eq") == 0) {
+            int p;
+            c = getint(c, &p, gnc, closure);
+            if(c < -1)
+                goto error;
+            filter->src_plen_ge = MAX(filter->src_plen_ge, p);
+            filter->src_plen_le = MIN(filter->src_plen_le, p);
+        } else if(strcmp(token, "src-le") == 0) {
+            int p;
+            c = getint(c, &p, gnc, closure);
+            if(c < -1)
+                goto error;
+            filter->src_plen_le = MIN(filter->src_plen_le, p);
+        } else if(strcmp(token, "src-ge") == 0) {
+            int p;
+            c = getint(c, &p, gnc, closure);
+            if(c < -1)
+                goto error;
+            filter->src_plen_ge = MAX(filter->src_plen_ge, p);
         } else if(strcmp(token, "neigh") == 0) {
             unsigned char *neigh = NULL;
             c = getip(c, &neigh, NULL, gnc, closure);
@@ -346,23 +381,36 @@ parse_filter(int c, gnc_t gnc, void *closure, struct filter **filter_return)
             filter->ifname = interface;
             filter->ifindex = if_nametoindex(interface);
         } else if(strcmp(token, "allow") == 0) {
-            filter->result = 0;
+            filter->action.add_metric = 0;
         } else if(strcmp(token, "deny") == 0) {
-            filter->result = INFINITY;
+            filter->action.add_metric = INFINITY;
         } else if(strcmp(token, "metric") == 0) {
             int metric;
             c = getint(c, &metric, gnc, closure);
             if(c < -1) goto error;
             if(metric <= 0 || metric > INFINITY)
                 goto error;
-            filter->result = metric;
+            filter->action.add_metric = metric;
+        } else if(strcmp(token, "src-prefix") == 0) {
+            int af;
+            c = getnet(c, &filter->action.src_prefix, &filter->action.src_plen,
+                       &af, gnc, closure);
+            if(c < -1)
+                goto error;
+            if(filter->af == AF_UNSPEC)
+                filter->af = af;
+            else if(filter->af != af)
+                goto error;
+            if(af == AF_INET && filter->action.src_plen == 96)
+                memset(&filter->action.src_prefix, 0, 16);
         } else {
             goto error;
         }
         free(token);
     }
     if(filter->af == 0) {
-        if(filter->plen_le < 128 || filter->plen_ge > 0)
+        if(filter->plen_le < 128 || filter->plen_ge > 0 ||
+           filter->src_plen_le < 128 || filter->src_plen_ge > 0)
             filter->af = AF_INET6;
     } else if(filter->af == AF_INET) {
         filter->plen_le += 96;
@@ -716,6 +764,18 @@ parse_option(int c, gnc_t gnc, void *closure, char *token)
         if(c < -1 || h < 0)
             goto error;
         change_smoothing_half_life(h);
+    } else if(strcmp(token, "first-table-number") == 0) {
+        int n;
+        c = getint(c, &n, gnc, closure);
+        if(c < -1 || n <= 0 || n + SRC_TABLE_NUM >= 254)
+            goto error;
+        src_table_idx = n;
+    } else if(strcmp(token, "first-rule-priority") == 0) {
+        int n;
+        c = getint(c, &n, gnc, closure);
+        if(c < -1 || n <= 0 || n + SRC_TABLE_NUM >= 32765)
+            goto error;
+        src_table_prio = n;
     } else {
         goto error;
     }
@@ -876,6 +936,7 @@ renumber_filters()
 static int
 filter_match(struct filter *f, 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 proto)
 {
     if(f->af) {
@@ -893,6 +954,11 @@ filter_match(struct filter *f, const unsigned char *id,
         if(!prefix || plen < f->plen || !in_prefix(prefix, f->prefix, f->plen))
             return 0;
     }
+    if(f->src_prefix) {
+        if(!src_prefix || src_plen < f->src_plen ||
+           !in_prefix(src_prefix, f->src_prefix, f->src_plen))
+            return 0;
+    }
     if(f->plen_ge > 0 || f->plen_le < 128) {
         if(!prefix)
             return 0;
@@ -901,6 +967,14 @@ filter_match(struct filter *f, const unsigned char *id,
         if(plen < f->plen_ge)
             return 0;
     }
+    if(f->src_plen_ge > 0 || f->src_plen_le < 128) {
+        if(!src_prefix)
+            return 0;
+        if(src_plen > f->src_plen_le)
+            return 0;
+        if(src_plen < f->src_plen_ge)
+            return 0;
+    }
     if(f->neigh) {
         if(!neigh || memcmp(f->neigh, neigh, 16) != 0)
             return 0;
@@ -928,34 +1002,49 @@ filter_match(struct filter *f, const unsigned char *id,
 static int
 do_filter(struct filter *f, const unsigned char *id,
           const unsigned char *prefix, unsigned short plen,
-          const unsigned char *neigh, unsigned int ifindex, int proto)
+          const unsigned char *src_prefix, unsigned short src_plen,
+          const unsigned char *neigh, unsigned int ifindex, int proto,
+          struct filter_result *result)
 {
+    if(result)
+        memset(result, 0, sizeof(struct filter_result));
+
     while(f) {
-        if(filter_match(f, id, prefix, plen, neigh, ifindex, proto))
-            return f->result;
+        if(filter_match(f, id, prefix, plen, src_prefix, src_plen,
+                        neigh, ifindex, proto)) {
+            if(result)
+                memcpy(result, &f->action, sizeof(struct filter_result));
+            return f->action.add_metric;
+        }
         f = f->next;
     }
+
     return -1;
 }
 
 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;
-    res = do_filter(input_filters, id, prefix, plen, neigh, ifindex, 0);
+    res = do_filter(input_filters, id, prefix, plen,
+                    src_prefix, src_plen, neigh, ifindex, 0, NULL);
     if(res < 0)
         res = 0;
     return res;
 }
 
 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);
+    res = do_filter(output_filters, id, prefix, plen,
+                    src_prefix, src_plen, NULL, ifindex, 0, NULL);
     if(res < 0)
         res = 0;
     return res;
@@ -963,11 +1052,13 @@ output_filter(const unsigned char *id, const unsigned char *prefix,
 
 int
 redistribute_filter(const unsigned char *prefix, unsigned short plen,
-                    unsigned int ifindex, int proto)
+                    const unsigned char *src_prefix, unsigned short src_plen,
+                    unsigned int ifindex, int proto,
+                    struct filter_result *result)
 {
     int res;
-    res = do_filter(redistribute_filters, NULL, prefix, plen, NULL,
-                    ifindex, proto);
+    res = do_filter(redistribute_filters, NULL, prefix, plen,
+                    src_prefix, src_plen, NULL, ifindex, proto, result);
     if(res < 0)
         res = INFINITY;
     return res;
@@ -982,6 +1073,7 @@ finalise_config()
 
     filter->proto = RTPROT_BABEL_LOCAL;
     filter->plen_le = 128;
+    filter->src_plen_le = 128;
     add_filter(filter, &redistribute_filters);
 
     while(interface_confs) {

configuration.h

@@ -20,6 +20,12 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */
 
+struct filter_result {
+    unsigned int add_metric; /* allow = 0, deny = INF, metric = <0..INF> */
+    unsigned char *src_prefix;
+    unsigned char src_plen;
+};
+
 struct filter {
     int af;
     char *ifname;
@@ -28,9 +34,12 @@ struct filter {
     unsigned char *prefix;
     unsigned char plen;
     unsigned char plen_ge, plen_le;
+    unsigned char *src_prefix;
+    unsigned char src_plen;
+    unsigned char src_plen_ge, src_plen_le;
     unsigned char *neigh;
     int proto;                  /* May be negative */
-    unsigned int result;
+    struct filter_result action;
     struct filter *next;
 };
 
@@ -42,9 +51,14 @@ 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,
-                        unsigned int ifindex, int proto);
+                    const unsigned char *src_prefix, unsigned short src_plen,
+                    unsigned int ifindex, int proto,
+                    struct filter_result *result);
 int finalise_config(void);

disambiguation.h

+/*
+Copyright (c) 2014 by Matthieu Boutier and Juliusz Chroboczek.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+int kinstall_route(struct babel_route *route);
+int kuninstall_route(struct babel_route *route);
+int kswitch_routes(struct babel_route *old, struct babel_route *new);
+int kchange_route_metric(struct babel_route *route,
+                         unsigned refmetric, unsigned cost, unsigned add);

interface.c

@@ -177,6 +177,40 @@ check_interface_channel(struct interface *ifp)
     return 0;
 }
 
+static int
+check_link_local_addresses(struct interface *ifp)
+{
+    struct kernel_route ll[32];
+    int rc, i;
+    if(ifp->ll)
+        free(ifp->ll);
+    ifp->numll = 0;
+    ifp->ll = NULL;
+    rc = kernel_addresses(ifp->name, ifp->ifindex, 1, ll, 32);
+    if(rc < 0) {
+        perror("kernel_addresses(link local)");
+        return -1;
+    } else if(rc == 0) {
+        fprintf(stderr, "Interface %s has no link-local address.\n",
+                ifp->name);
+        /* Most probably DAD hasn't finished yet.  Reschedule us
+           real soon. */
+        schedule_interfaces_check(2000, 0);
+        return -1;
+    } else {
+        ifp->ll = malloc(16 * rc);
+        if(ifp->ll == NULL) {
+            perror("malloc(ll)");
+        } else {
+            for(i = 0; i < rc; i++)
+                memcpy(ifp->ll[i], ll[i].prefix, 16);
+            ifp->numll = rc;
+        }
+    }
+
+    return 0;
+}
+
 int
 interface_up(struct interface *ifp, int up)
 {
@@ -192,7 +226,6 @@ interface_up(struct interface *ifp, int up)
         ifp->flags &= ~IF_UP;
 
     if(up) {
-        struct kernel_route ll[32];
         if(ifp->ifindex <= 0) {
             fprintf(stderr,
                     "Upping unknown interface %s.\n", ifp->name);
@@ -329,32 +362,10 @@ interface_up(struct interface *ifp, int up)
             ifp->max_rtt_penalty > 0))
             ifp->flags |= IF_TIMESTAMPS;
 
-        if(ifp->ll)
-            free(ifp->ll);
-        ifp->numll = 0;
-        ifp->ll = NULL;
-        rc = kernel_addresses(ifp->name, ifp->ifindex, 1, ll, 32);
+        rc = check_link_local_addresses(ifp);
         if(rc < 0) {
-            perror("kernel_addresses(link local)");
             goto fail;
-        } else if(rc == 0) {
-            fprintf(stderr, "Interface %s has no link-local address.\n",
-                    ifp->name);
-            /* Most probably DAD hasn't finished yet.  Reschedule us
-               real soon. */
-            goto fail_retry;
-        } else {
-            ifp->ll = malloc(16 * rc);
-            if(ifp->ll == NULL) {
-                perror("malloc(ll)");
-            } else {
-                int i;
-                for(i = 0; i < rc; i++)
-                    memcpy(ifp->ll[i], ll[i].prefix, 16);
-                ifp->numll = rc;
-            }
         }
-
         memset(&mreq, 0, sizeof(mreq));
         memcpy(&mreq.ipv6mr_multiaddr, protocol_group, 16);
         mreq.ipv6mr_interface = ifp->ifindex;
@@ -380,8 +391,8 @@ 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_request(ifp, NULL, 0);
+            send_update(ifp, 0, NULL, 0, NULL, 0);
+        send_request(ifp, NULL, 0, NULL, 0);
     } else {
         flush_interface_routes(ifp, 0);
         ifp->buffered = 0;
@@ -411,8 +422,6 @@ interface_up(struct interface *ifp, int up)
 
     return 1;
 
- fail_retry:
-    schedule_interfaces_check(2000, 0);
  fail:
     assert(up);
     interface_up(ifp, 0);
@@ -462,12 +471,13 @@ check_interfaces(void)
 
         if(if_up(ifp)) {
             /* Bother, said Pooh.  We should probably check for a change
-               in link-local and IPv4 addresses at this point. */
+               in IPv4 addresses at this point. */
+            check_link_local_addresses(ifp);
             check_interface_channel(ifp);
             rc = check_interface_ipv4(ifp);
             if(rc > 0) {
-                send_request(ifp, NULL, 0);
-                send_update(ifp, 0, NULL, 0);
+                send_request(ifp, NULL, 0, NULL, 0);
+                send_update(ifp, 0, NULL, 0, NULL, 0);
             }
         }
     }

interface.h

@@ -23,8 +23,10 @@ THE SOFTWARE.
 struct buffered_update {
     unsigned char id[8];
     unsigned char prefix[16];
+    unsigned char src_prefix[16];
     unsigned char plen;
-    unsigned char pad[3];
+    unsigned char src_plen; /* 0 <=> no src prefix */
+    unsigned char pad[2];
 };
 
 struct interface_conf {
@@ -94,6 +96,7 @@ struct interface {
     time_t bucket_time;
     unsigned int bucket;
     time_t last_update_time;
+    time_t last_specific_update_time;
     unsigned short hello_seqno;
     unsigned hello_interval;
     unsigned update_interval;

kernel.c

@@ -32,6 +32,9 @@ THE SOFTWARE.
 #include "kernel_socket.c"
 #endif
 
+int src_table_idx = 10;
+int src_table_prio = 100;
+
 /* Like gettimeofday, but returns monotonic time.  If POSIX clocks are not
    available, falls back to gettimeofday but enforces monotonicity. */
 int

kernel.h

@@ -28,6 +28,8 @@ THE SOFTWARE.
 struct kernel_route {
     unsigned char prefix[16];
     int plen;
+    unsigned char src_prefix[16];
+    int src_plen; /* no source prefix <=> src_plen == 0 */
     int metric;
     unsigned int ifindex;
     int proto;
@@ -41,6 +43,7 @@ struct kernel_route {
 #define CHANGE_LINK  (1 << 0)
 #define CHANGE_ROUTE (1 << 1)
 #define CHANGE_ADDR  (1 << 2)
+#define CHANGE_RULE  (1 << 3)
 
 #ifndef MAX_IMPORT_TABLES
 #define MAX_IMPORT_TABLES 10
@@ -49,6 +52,9 @@ struct kernel_route {
 extern int export_table, import_tables[MAX_IMPORT_TABLES], import_table_count;
 
 int add_import_table(int table);
+#define SRC_TABLE_NUM 10
+extern int src_table_idx; /* number of the first table */
+extern int src_table_prio; /* first prio range */
 
 int kernel_setup(int setup);
 int kernel_setup_socket(int setup);
@@ -60,6 +66,7 @@ int kernel_interface_mtu(const char *ifname, int ifindex);
 int kernel_interface_wireless(const char *ifname, int ifindex);
 int kernel_interface_channel(const char *ifname, int ifindex);
 int kernel_route(int operation, const unsigned char *dest, unsigned short plen,
+                 const unsigned char *src, unsigned short src_plen,
                  const unsigned char *gate, int ifindex, unsigned int metric,
                  const unsigned char *newgate, int newifindex,
                  unsigned int newmetric);

kernel_socket.c

@@ -29,8 +29,6 @@ THE SOFTWARE.
 #include <unistd.h>
 #include <fcntl.h>
 #include <time.h>
-
-
 #include <strings.h>
 #include <netinet/in.h>
 #include <netinet/icmp6.h>
@@ -53,7 +51,6 @@ THE SOFTWARE.
 
 static int get_sdl(struct sockaddr_dl *sdl, char *ifname);
 
-
 static const unsigned char v4prefix[16] =
     {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
 
@@ -387,6 +384,7 @@ kernel_interface_channel(const char *ifname, int ifindex)
 
 int
 kernel_route(int operation, const unsigned char *dest, unsigned short plen,
+             const unsigned char *src, unsigned short src_plen,
              const unsigned char *gate, int ifindex, unsigned int metric,
              const unsigned char *newgate, int newifindex,
              unsigned int newmetric)
@@ -403,6 +401,12 @@ kernel_route(int operation, const unsigned char *dest, unsigned short plen,
         {{{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
             0x00, 0x00, 0x00, 0x00, 0x7f, 0x00, 0x00, 0x01 }}};
 
+    /* Source-specific routes are not implemented yet for BSD. */
+    if(src_plen > 0) {
+        errno = ENOSYS;
+        return -1;
+    }
+
     /* Check that the protocol family is consistent. */
     if(plen >= 96 && v4mapped(dest)) {
         if(!v4mapped(gate)) {
@@ -427,9 +431,11 @@ kernel_route(int operation, const unsigned char *dest, unsigned short plen,
 
         /* Avoid atomic route changes that is buggy on OS X. */
         kernel_route(ROUTE_FLUSH, dest, plen,
+                     src, src_plen,
                      gate, ifindex, metric,
                      NULL, 0, 0);
         return kernel_route(ROUTE_ADD, dest, plen,
+                            src, src_plen,
                             newgate, newifindex, newmetric,
                             NULL, 0, 0);
 
@@ -668,7 +674,7 @@ kernel_routes(struct kernel_route *routes, int maxroutes)
     size_t len;
     struct rt_msghdr *rtm;
     int rc, i;
-    
+
     mib[0] = CTL_NET;
     mib[1] = PF_ROUTE;
     mib[2] = 0;

local.c

@@ -185,12 +185,14 @@ local_notify_xroute_1(int s, struct xroute *xroute, int kind)
 {
     char buf[512];
     int rc;
+    const char *dst_prefix = format_prefix(xroute->prefix,
+                                           xroute->plen);
+    const char *src_prefix = format_prefix(xroute->src_prefix,
+                                           xroute->src_plen);
 
-    rc = snprintf(buf, 512, "%s xroute %s prefix %s metric %d\n",
-                  local_kind(kind),
-                  format_prefix(xroute->prefix, xroute->plen),
-                  format_prefix(xroute->prefix, xroute->plen),
-                  xroute->metric);
+    rc = snprintf(buf, 512, "%s xroute %s-%s prefix %s from %s metric %d\n",
+                  local_kind(kind), dst_prefix, src_prefix,
+                  dst_prefix, src_prefix, xroute->metric);
 
     if(rc < 0 || rc >= 512)
         goto fail;
@@ -218,14 +220,17 @@ local_notify_route_1(int s, struct babel_route *route, int kind)
 {
     char buf[512];
     int rc;
+    const char *dst_prefix = format_prefix(route->src->prefix,
+                                           route->src->plen);
+    const char *src_prefix = format_prefix(route->src->src_prefix,
+                                           route->src->src_plen);
 
     rc = snprintf(buf, 512,
-                  "%s route %s-%lx prefix %s installed %s "
+                  "%s route %s-%lx-%s prefix %s from %s installed %s "
                   "id %s metric %d refmetric %d via %s if %s\n",
                   local_kind(kind),
-                  format_prefix(route->src->prefix, route->src->plen),
-                  (unsigned long)route->neigh,
-                  format_prefix(route->src->prefix, route->src->plen),
+                  dst_prefix, (unsigned long)route->neigh, src_prefix,
+                  dst_prefix, src_prefix,
                   route->installed ? "yes" : "no",
                   format_eui64(route->src->id),
                   route_metric(route), route->refmetric,

message.h

@@ -39,6 +39,10 @@ THE SOFTWARE.
 #define MESSAGE_UPDATE 8
 #define MESSAGE_REQUEST 9
 #define MESSAGE_MH_REQUEST 10
+/* 11 and 12 are for authentication */
+#define MESSAGE_UPDATE_SRC_SPECIFIC 13
+#define MESSAGE_REQUEST_SRC_SPECIFIC 14
+#define MESSAGE_MH_REQUEST_SRC_SPECIFIC 15
 
 /* Protocol extension through sub-TLVs. */
 #define SUBTLV_PAD1 0
@@ -67,30 +71,44 @@ 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);
 void send_ihu(struct neighbour *neigh, struct interface *ifp);
 void send_marginal_ihu(struct interface *ifp);
 void send_request(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_unicast_request(struct neighbour *neigh,
-                          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_multihop_request(struct interface *ifp,
                            const unsigned char *prefix, unsigned char plen,
+                           const unsigned char *src_prefix,
+                           unsigned char src_plen,
                            unsigned short seqno, const unsigned char *id,
                            unsigned short hop_count);
 void
 send_unicast_multihop_request(struct neighbour *neigh,
                               const unsigned char *prefix, unsigned char plen,
+                              const unsigned char *src_prefix,
+                              unsigned char src_plen,
                               unsigned short seqno, const unsigned char *id,
                               unsigned short hop_count);
 void send_request_resend(struct neighbour *neigh,
                          const unsigned char *prefix, unsigned char plen,
+                         const unsigned char *src_prefix,
+                         unsigned char src_plen,
                          unsigned short seqno, unsigned char *id);
 void handle_request(struct neighbour *neigh, const unsigned char *prefix,
-                    unsigned char plen, unsigned char hop_count,
+                    unsigned char plen,
+                    const unsigned char *src_prefix, unsigned char src_plen,
+                    unsigned char hop_count,
                     unsigned short seqno, const unsigned char *id);

neighbour.c

@@ -193,7 +193,7 @@ update_neighbour(struct neighbour *neigh, int hello, int hello_interval)
     if((neigh->reach & 0xFC00) == 0xC000) {
         /* This is a newish neighbour, let's request a full route dump.
            We ought to avoid this when the network is dense */
-        send_unicast_request(neigh, NULL, 0);
+        send_unicast_request(neigh, NULL, 0, NULL, 0);
         send_ihu(neigh, NULL);
     }
     return rc;

resend.c

@@ -38,10 +38,13 @@ struct resend *to_resend = NULL;
 
 static int
 resend_match(struct resend *resend,
-             int kind, const unsigned char *prefix, unsigned char plen)
+             int kind, const unsigned char *prefix, unsigned char plen,
+             const unsigned char *src_prefix, unsigned char src_plen)
 {
     return (resend->kind == kind &&
-            resend->plen == plen && memcmp(resend->prefix, prefix, 16) == 0);
+            resend->plen == plen && memcmp(resend->prefix, prefix, 16) == 0 &&
+            resend->src_plen == src_plen &&
+            memcmp(resend->src_prefix, src_prefix, 16) == 0);
 }
 
 /* This is called by neigh.c when a neighbour is flushed */
@@ -54,14 +57,15 @@ flush_resends(struct neighbour *neigh)
 
 static struct resend *
 find_resend(int kind, const unsigned char *prefix, unsigned char plen,
-             struct resend **previous_return)
+            const unsigned char *src_prefix, unsigned char src_plen,
+            struct resend **previous_return)
 {
     struct resend *current, *previous;
 
     previous = NULL;
     current = to_resend;
     while(current) {
-        if(resend_match(current, kind, prefix, plen)) {
+        if(resend_match(current, kind, prefix, plen, src_prefix, src_plen)) {
             if(previous_return)
                 *previous_return = previous;
             return current;
@@ -75,13 +79,16 @@ 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);
+    return find_resend(RESEND_REQUEST, prefix, plen, src_prefix, src_plen,
+                       previous_return);
 }
 
 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)
 {
@@ -89,15 +96,18 @@ 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, src_prefix, src_plen, 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)
         delay = 0xFFFF;
 
-    resend = find_resend(kind, prefix, plen, NULL);
+    resend = find_resend(kind, prefix, plen, src_prefix, src_plen, NULL);
     if(resend) {
         if(resend->delay && delay)
             resend->delay = MIN(resend->delay, delay);
@@ -125,6 +135,8 @@ record_resend(int kind, const unsigned char *prefix, unsigned char plen,
         resend->delay = delay;
         memcpy(resend->prefix, prefix, 16);
         resend->plen = plen;
+        memcpy(resend->src_prefix, src_prefix, 16);
+        resend->src_plen = src_plen;
         resend->seqno = seqno;
         if(id)
             memcpy(resend->id, id, 8);
@@ -157,11 +169,12 @@ resend_expired(struct resend *resend)
 
 int
 unsatisfied_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 resend *request;
 
-    request = find_request(prefix, plen, NULL);
+    request = find_request(prefix, plen, src_prefix, src_plen, NULL);
     if(request == NULL || resend_expired(request))
         return 0;
 
@@ -176,11 +189,12 @@ unsatisfied_request(const unsigned char *prefix, unsigned char plen,
 int
 request_redundant(struct interface *ifp,
                   const unsigned char *prefix, unsigned char plen,
+                  const unsigned char *src_prefix, unsigned char src_plen,
                   unsigned short seqno, const unsigned char *id)
 {
     struct resend *request;
 
-    request = find_request(prefix, plen, NULL);
+    request = find_request(prefix, plen, src_prefix, src_plen, NULL);
     if(request == NULL || resend_expired(request))
         return 0;
 
@@ -205,12 +219,13 @@ 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, src_prefix, src_plen, &previous);
     if(request == NULL)
         return 0;
 
@@ -293,11 +308,13 @@ do_resend()
                 case RESEND_REQUEST:
                     send_multihop_request(resend->ifp,
                                           resend->prefix, resend->plen,
+                                          resend->src_prefix, resend->src_plen,
                                           resend->seqno, resend->id, 127);
                     break;
                 case RESEND_UPDATE:
                     send_update(resend->ifp, 1,
-                                resend->prefix, resend->plen);
+                                resend->prefix, resend->plen,
+                                resend->src_prefix, resend->src_plen);
                     break;
                 default: abort();
                 }

resend.h

@@ -33,6 +33,8 @@ struct resend {
     struct timeval time;
     unsigned char prefix[16];
     unsigned char plen;
+    unsigned char src_prefix[16];
+    unsigned char src_plen;
     unsigned short seqno;
     unsigned char id[8];
     struct interface *ifp;
@@ -42,17 +44,22 @@ struct resend {
 extern struct timeval resend_time;
 
 struct resend *find_request(const unsigned char *prefix, unsigned char plen,
-                            struct resend **previous_return);
+                    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,
-                   unsigned short seqno, const unsigned char *id,
-                   struct interface *ifp, int delay);
+                  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,
+                        const unsigned char *src_prefix, unsigned char src_plen,
                         unsigned short seqno, const unsigned char *id);
 int request_redundant(struct interface *ifp,
                       const unsigned char *prefix, unsigned char plen,
+                      const unsigned char *src_prefix, unsigned char src_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.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,
-                         struct neighbour *neigh, const unsigned char *nexthop);
+                        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_fixed_dst, int exclusive_min);
 int installed_routes_estimate(void);
 void flush_route(struct babel_route *route);
 void flush_all_routes(void);
@@ -81,6 +87,7 @@ void flush_interface_routes(struct interface *ifp, int v4only);
 struct route_stream *route_stream(int installed);
 struct babel_route *route_stream_next(struct route_stream *stream);
 void route_stream_done(struct route_stream *stream);
+int metric_to_kernel(int metric);
 void install_route(struct babel_route *route);
 void uninstall_route(struct babel_route *route);
 int route_feasible(struct babel_route *route);
@@ -93,6 +100,8 @@ 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 +110,8 @@ 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.c

@@ -28,6 +28,7 @@ THE SOFTWARE.
 #include <stdio.h>
 #include <unistd.h>
 #include <limits.h>
+#include <assert.h>
 
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -488,3 +489,30 @@ daemonise()
 
     return 1;
 }
+
+enum prefix_status
+prefix_cmp(const unsigned char *p1, unsigned char plen1,
+           const unsigned char *p2, unsigned char plen2)
+{
+    int min = MIN(plen1, plen2);
+    unsigned char mask = 0xFF;
+    int i = 0;
+
+    while(i < min / 8) {
+        if(p1[i] != p2[i])
+            return PST_DISJOINT;
+        i++;
+    }
+    min -= i * 8;
+    if(min != 0) {
+        mask <<= 8 - min;
+        if((p1[i] & mask) != (p2[i] & mask))
+            return PST_DISJOINT;
+    }
+
+    if(plen1 < plen2)
+        return PST_LESS_SPECIFIC;
+    if(plen1 > plen2)
+        return PST_MORE_SPECIFIC;
+    return PST_EQUALS;
+}

util.h

@@ -111,6 +111,17 @@ 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,
+    PST_EQUALS        = 1 << 1,
+    PST_MORE_SPECIFIC = 1 << 2,
+    PST_LESS_SPECIFIC = 1 << 3,
+};
+enum prefix_status
+prefix_cmp(const unsigned char *p1, unsigned char plen1,
+           const unsigned char *p2, unsigned char plen2);
 
 /* If debugging is disabled, we want to avoid calling format_address
    for every omitted debugging message.  So debug is a macro.  But

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;
@@ -163,14 +169,15 @@ check_xroutes(int send_updates)
 {
     int i, j, metric, export, change = 0, rc;
     struct kernel_route *routes;
-    int numroutes;
+    struct filter_result filter_result = {0};
+    int numroutes, numaddresses;
     static int maxroutes = 8;
     const int maxmaxroutes = 16 * 1024;
 
     debugf("\nChecking kernel routes.\n");
 
  again:
-    routes = malloc(maxroutes * sizeof(struct kernel_route));
+    routes = calloc(maxroutes, sizeof(struct kernel_route));
     if(routes == NULL)
         return -1;
 
@@ -185,6 +192,8 @@ check_xroutes(int send_updates)
     if(numroutes >= maxroutes)
         goto resize;
 
+    numaddresses = numroutes;
+
     rc = kernel_routes(routes + numroutes, maxroutes - numroutes);
     if(rc < 0)
         fprintf(stderr, "Couldn't get kernel routes.\n");
@@ -194,13 +203,30 @@ check_xroutes(int send_updates)
     if(numroutes >= maxroutes)
         goto resize;
 
+    /* Apply filter to kernel routes (e.g. change the source prefix). */
+
+    for(i = numaddresses; i < numroutes; i++) {
+        filter_result.src_prefix = NULL;
+        redistribute_filter(routes[i].prefix, routes[i].plen,
+                            routes[i].src_prefix, routes[i].src_plen,
+                            routes[i].ifindex, routes[i].proto,
+                            &filter_result);
+        if(filter_result.src_prefix) {
+            memcpy(routes[i].src_prefix, filter_result.src_prefix, 16);
+            routes[i].src_plen = filter_result.src_plen;
+        }
+
+    }
+
     /* Check for any routes that need to be flushed */
 
     i = 0;
     while(i < numxroutes) {
         export = 0;
         metric = redistribute_filter(xroutes[i].prefix, xroutes[i].plen,
-                                     xroutes[i].ifindex, xroutes[i].proto);
+                                     xroutes[i].src_prefix, xroutes[i].src_plen,
+                                     xroutes[i].ifindex, xroutes[i].proto,
+                                     NULL);
         if(metric < INFINITY && metric == xroutes[i].metric) {
             for(j = 0; j < numroutes; j++) {
                 if(xroutes[i].plen == routes[j].plen &&
@@ -215,17 +241,20 @@ 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 +267,17 @@ 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].ifindex, routes[i].proto);
+                                     routes[i].src_prefix, routes[i].src_plen,
+                                     routes[i].ifindex, routes[i].proto, NULL);
         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 +285,8 @@ 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();