Add source-restricted routes
authorSteven Barth <steven@midlink.org>
Fri, 18 Oct 2013 10:09:42 +0000 (12:09 +0200)
committerSteven Barth <steven@midlink.org>
Fri, 18 Oct 2013 10:09:42 +0000 (12:09 +0200)
dummy/netifd-proto.sh
interface-ip.c
interface-ip.h
iprule.h
ubus.c

index d8b540dd883c57edc77c4e4937aa08b6c637bc65..6f20de91a7ce464fa4612dae7a2bff83f01b1ba5 100755 (executable)
@@ -143,8 +143,9 @@ proto_add_ipv6_route() {
        local gw="$3"
        local metric="$4"
        local valid="$5"
+       local source="$6"
 
-       append PROTO_ROUTE6 "$target/$mask/$gw/$metric/$valid"
+       append PROTO_ROUTE6 "$target/$mask/$gw/$metric/$valid/$source"
 }
 
 proto_add_ipv6_prefix() {
@@ -218,6 +219,8 @@ _proto_push_route() {
        local metric="${str%%/*}"
        str="${str#*/}"
        local valid="${str%%/*}"
+       str="${str#*/}"
+       local source="${str}"
 
        json_add_object ""
        json_add_string target "$target"
@@ -225,6 +228,7 @@ _proto_push_route() {
        [ -n "$gw" ] && json_add_string gateway "$gw"
        [ -n "$metric" ] && json_add_int metric "$metric"
        [ -n "$valid" ] && json_add_int valid "$valid"
+       [ -n "$source" ] && json_add_string source "$source"
        json_close_object
 }
 
index 185a9a7ebd4716d0250a78d91ed93a4c6d276833..60902f994e41cdb4191f6c5640a4c5527072fdc7 100644 (file)
@@ -37,6 +37,7 @@ enum {
        ROUTE_MTU,
        ROUTE_VALID,
        ROUTE_TABLE,
+       ROUTE_SOURCE,
        __ROUTE_MAX
 };
 
@@ -49,6 +50,7 @@ static const struct blobmsg_policy route_attr[__ROUTE_MAX] = {
        [ROUTE_MTU] = { .name = "mtu", .type = BLOBMSG_TYPE_INT32 },
        [ROUTE_TABLE] = { .name = "table", .type = BLOBMSG_TYPE_STRING },
        [ROUTE_VALID] = { .name = "valid", .type = BLOBMSG_TYPE_INT32 },
+       [ROUTE_SOURCE] = { .name = "source", .type = BLOBMSG_TYPE_STRING },
 };
 
 const struct uci_blob_param_list route_attr_list = {
@@ -58,6 +60,7 @@ const struct uci_blob_param_list route_attr_list = {
 
 
 struct list_head prefixes = LIST_HEAD_INIT(prefixes);
+static struct list_head source_tables = LIST_HEAD_INIT(source_tables);
 static struct device_prefix *ula_prefix = NULL;
 static struct uloop_timeout valid_until_timeout;
 
@@ -92,7 +95,7 @@ match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
 }
 
 static int set_ip_source_policy(bool add, bool v6, unsigned int priority,
-               const union if_addr *addr, uint8_t mask, struct interface *iface,
+               const union if_addr *addr, uint8_t mask, unsigned int table,
                struct interface *in_iface, const char *action)
 {
        struct iprule rule = {
@@ -106,9 +109,9 @@ static int set_ip_source_policy(bool add, bool v6, unsigned int priority,
                rule.src_mask = mask;
        }
 
-       if (iface) {
+       if (table) {
                rule.flags |= IPRULE_LOOKUP;
-               rule.lookup = (v6) ? iface->ip6table : iface->ip4table;
+               rule.lookup = table;
 
                if (!rule.lookup)
                        return 0;
@@ -195,6 +198,72 @@ __find_ip_route_target(struct interface_ip_settings *ip, union if_addr *a,
        }
 }
 
+static struct device_source_table*
+find_source_table(const struct device_route *route)
+{
+       struct device_source_table key = {
+               .v6 = (route->flags & DEVADDR_FAMILY) == DEVADDR_INET6,
+               .addr = route->source,
+               .mask = route->sourcemask
+       };
+       struct device_source_table *c;
+       list_for_each_entry(c, &source_tables, head)
+               if (!memcmp(&c->v6, &key.v6, sizeof(key) -
+                               offsetof(struct device_source_table, v6)))
+                       return c;
+       return NULL;
+}
+
+static uint32_t
+get_source_table(const struct device_route *route)
+{
+       if (route->table || route->sourcemask == 0)
+               return route->table;
+
+       struct device_source_table *tbl = find_source_table(route);
+
+       if (!tbl) {
+               tbl = calloc(1, sizeof(*tbl));
+               tbl->addr = route->source;
+               tbl->mask = route->sourcemask;
+               tbl->v6 = (route->flags & DEVADDR_FAMILY) == DEVADDR_INET6;
+               tbl->table = IPRULE_PRIORITY_SOURCE | (((~tbl->mask) & 0x7f) << 20);
+
+               struct list_head *before = NULL;
+               struct device_source_table *c;
+               list_for_each_entry(c, &source_tables, head) {
+                       if (c->table > tbl->table) {
+                               before = &c->head;
+                               break;
+                       } else if (c->table == tbl->table) {
+                               ++tbl->table;
+                       }
+               }
+
+               if (!before)
+                       before = &source_tables;
+
+               list_add_tail(&tbl->head, before);
+               set_ip_source_policy(true, tbl->v6, tbl->table, &tbl->addr,
+                               tbl->mask, tbl->table, NULL, NULL);
+       }
+
+       ++tbl->refcount;
+       return tbl->table;
+}
+
+static void
+put_source_table(const struct device_route *route)
+{
+       struct device_source_table *tbl = find_source_table(route);
+       if (tbl && tbl->table == route->table && --tbl->refcount == 0) {
+               set_ip_source_policy(false, tbl->v6, tbl->table, &tbl->addr,
+                               tbl->mask, tbl->table, NULL, NULL);
+               list_del(&tbl->head);
+               free(tbl);
+       }
+}
+
 static bool
 interface_ip_find_addr_target(struct interface *iface, union if_addr *a, bool v6)
 {
@@ -329,7 +398,20 @@ interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
        }
 
        // Use source-based routing
-       if (is_proto_route) {
+       if ((cur = tb[ROUTE_SOURCE]) != NULL) {
+               char *saveptr, *source = alloca(blobmsg_data_len(cur));
+               memcpy(source, blobmsg_data(cur), blobmsg_data_len(cur));
+
+               const char *addr = strtok_r(source, "/", &saveptr);
+               const char *mask = strtok_r(NULL, "/", &saveptr);
+
+               if (inet_pton(af, addr, &route->source) < 1) {
+                       DPRINTF("Failed to parse route source: %s\n", addr);
+                       goto error;
+               }
+
+               route->sourcemask = atoi(mask);
+       } else if (is_proto_route) {
                route->table = (v6) ? iface->ip6table : iface->ip4table;
                route->flags |= DEVROUTE_SRCTABLE;
        }
@@ -351,6 +433,11 @@ interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
                        route->valid_until = valid_until;
        }
 
+       if (route->sourcemask) {
+               route->table = get_source_table(route);
+               route->flags |= DEVROUTE_SRCTABLE;
+       }
+
        vlist_add(&ip->route, &route->node, route);
        return;
 
@@ -379,6 +466,13 @@ route_cmp(const void *k1, const void *k2, void *ptr)
        if (r1->flags != r2->flags)
                return r2->flags - r1->flags;
 
+       if (r1->sourcemask != r2->sourcemask)
+               return r1->sourcemask - r2->sourcemask;
+
+       int maskcmp = memcmp(&r1->source, &r2->source, sizeof(r1->source));
+       if (maskcmp)
+               return maskcmp;
+
        return memcmp(&r1->addr, &r2->addr, sizeof(r1->addr));
 }
 
@@ -478,9 +572,10 @@ interface_update_proto_addr(struct vlist_tree *tree,
                        //only the network-rule will cause packets to be routed through the
                        //first matching network (source IP matches both masks).
                        set_ip_source_policy(false, v6, IPRULE_PRIORITY_ADDR, &a_old->addr,
-                               (v6) ? 128 : 32, iface, NULL, NULL);
+                               (v6) ? 128 : 32, (v6) ? iface->ip6table : iface->ip4table,
+                                               NULL, NULL);
                        set_ip_source_policy(false, v6, IPRULE_PRIORITY_NW, &a_old->addr,
-                               a_old->mask, iface, NULL, NULL);
+                               a_old->mask, (v6) ? iface->ip6table : iface->ip4table, NULL, NULL);
 
                        system_del_address(dev, a_old);
                }
@@ -497,9 +592,11 @@ interface_update_proto_addr(struct vlist_tree *tree,
                                        v6 = true;
 
                                set_ip_source_policy(true, v6, IPRULE_PRIORITY_ADDR, &a_new->addr,
-                                               (v6) ? 128 : 32, iface, NULL, NULL);
+                                       (v6) ? 128 : 32, (v6) ? iface->ip6table : iface->ip4table,
+                                                       NULL, NULL);
                                set_ip_source_policy(true, v6, IPRULE_PRIORITY_NW, &a_new->addr,
-                                               a_new->mask, iface, NULL, NULL);
+                                       a_new->mask, (v6) ? iface->ip6table : iface->ip4table,
+                                                       NULL, NULL);
                        }
 
                        if ((a_new->flags & DEVADDR_OFFLINK) || iface->metric)
@@ -541,6 +638,8 @@ interface_update_proto_route(struct vlist_tree *tree,
        if (node_old) {
                if (!(route_old->flags & DEVADDR_EXTERNAL) && route_old->enabled && !keep)
                        system_del_route(dev, route_old);
+
+               put_source_table(route_old);
                free(route_old);
        }
 
@@ -611,10 +710,10 @@ interface_set_prefix_address(struct device_prefix_assignment *assignment,
                system_add_address(l3_downlink, &addr);
                if (prefix->iface) {
                        set_ip_source_policy(false, true, IPRULE_PRIORITY_NW, &addr.addr,
-                                                       addr.mask, prefix->iface, iface, NULL);
+                                       addr.mask, prefix->iface->ip6table, iface, NULL);
 
                        set_ip_source_policy(false, true, IPRULE_PRIORITY_REJECT, &addr.addr,
-                                                       addr.mask, NULL, iface, "unreachable");
+                                                       addr.mask, 0, iface, "unreachable");
                }
 
                assignment->enabled = false;
@@ -622,10 +721,10 @@ interface_set_prefix_address(struct device_prefix_assignment *assignment,
                system_add_address(l3_downlink, &addr);
                if (prefix->iface && !assignment->enabled) {
                        set_ip_source_policy(true, true, IPRULE_PRIORITY_REJECT, &addr.addr,
-                                       addr.mask, NULL, iface, "unreachable");
+                                       addr.mask, 0, iface, "unreachable");
 
                        set_ip_source_policy(true, true, IPRULE_PRIORITY_NW, &addr.addr,
-                                       addr.mask, prefix->iface, iface, NULL);
+                                       addr.mask, prefix->iface->ip6table, iface, NULL);
                }
                if (uplink && uplink->l3_dev.dev) {
                        int mtu = system_update_ipv6_mtu(
@@ -1101,7 +1200,7 @@ void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
                set_ip_lo_policy(enabled, false, ip->iface);
 
                set_ip_source_policy(enabled, true, IPRULE_PRIORITY_REJECT + ip->iface->l3_dev.dev->ifindex,
-                       NULL, 0, NULL, ip->iface, "failed_policy");
+                       NULL, 0, 0, ip->iface, "failed_policy");
        }
 }
 
index c78a076293cd0dcffdcd60330f3238c8bbfd00ac..b36c515f3d5b1ebf12dc69dd3978882360cead65 100644 (file)
@@ -108,6 +108,17 @@ struct device_route {
        int metric; // there can be multiple routes to the same target
        unsigned int table;
        unsigned int mask;
+       unsigned int sourcemask;
+       union if_addr addr;
+       union if_addr source;
+};
+
+struct device_source_table {
+       struct list_head head;
+       uint32_t table;
+       uint16_t refcount;
+       uint8_t v6;
+       uint8_t mask;
        union if_addr addr;
 };
 
index d6a8485cd6f4bcf2a534b742326ab64084a33392..3381ae33f04302cad879ab61ba7eb817fcca08c0 100644 (file)
--- a/iprule.h
+++ b/iprule.h
@@ -19,7 +19,8 @@
 
 #define IPRULE_PRIORITY_ADDR 80000
 #define IPRULE_PRIORITY_NW 90000
-#define IPRULE_PRIORITY_REJECT 2000000000
+#define IPRULE_PRIORITY_SOURCE 4026531840
+#define IPRULE_PRIORITY_REJECT 4200000000
 
 enum iprule_flags {
        /* address family for rule */
diff --git a/ubus.c b/ubus.c
index a26c3dd276fe6ec55011e6caffc2ec2e5bf852fc..513b40cc25ccd988ff28d87462b2548bf7c39856 100644 (file)
--- a/ubus.c
+++ b/ubus.c
@@ -488,6 +488,11 @@ interface_ip_dump_route_list(struct interface_ip_settings *ip, bool enabled)
                if (route->valid_until)
                        blobmsg_add_u32(&b, "valid", route->valid_until - now);
 
+               buf = blobmsg_alloc_string_buffer(&b, "source", buflen);
+               inet_ntop(af, &route->source, buf, buflen);
+               snprintf(buf + strlen(buf), 4, "/%u", route->sourcemask);
+               blobmsg_add_string_buffer(&b);
+
                blobmsg_close_table(&b, r);
        }
 }
@@ -727,6 +732,7 @@ netifd_handle_status(struct ubus_context *ctx, struct ubus_object *obj,
        return 0;
 }
 
+
 static int
 netifd_handle_dump(struct ubus_context *ctx, struct ubus_object *obj,
                     struct ubus_request_data *req, const char *method,