'GET' option for 'rt' command

A '--get' switch for the 'rt' to match a particular route and dump it.
Currently, only for inet and inet6 routes.

Change-Id: I3b53dda635f4f4af5b7f79ddf47e14313f372f81
Partial-BUG: #1548757

Support GET for L2 routes

Support 'GET' operation for a specific route in the vRouter bridge
table too.

Also, support giving a specific prefix length to the route and return
a match based on that specific prefix.

Change-Id: I93980925e70f45482c372ba3beeca8bfbd3028b2
Closes-BUG: #1548757

dp-core/vr_bridge.c

@@ -270,8 +270,10 @@ bridge_table_get(unsigned int vrf_id, struct vr_route_req *rt)
     struct vr_nexthop *nh;
 
     nh = bridge_table_lookup(vrf_id, rt);
-    if (nh)
+    if (nh) {
         rt->rtr_req.rtr_nh_id = rt->rtr_nh->nh_id;
+        return 0;
+    }
 
     return -ENOENT;
 }

dp-core/vr_ip_mtrie.c

@@ -874,6 +874,75 @@ mtrie_stats_dump(struct vr_rtable *rtable, vr_vrf_stats_req *req)
 
     return 0;
 }
+
+static struct vr_nexthop *
+__mtrie_lookup(struct vr_route_req *rt, struct ip_bucket *bkt, unsigned int level)
+{
+    unsigned int i, limit, index;
+    unsigned long ptr;
+
+    struct ip_bucket_entry *ent;
+    struct mtrie_bkt_info *ip_bkt_info;
+    struct vr_nexthop *ret_nh = NULL;
+
+    if (!bkt || level >= ip_bkt_get_max_level(rt->rtr_req.rtr_family))
+        return NULL;
+
+    ip_bkt_info = ip_bkt_info_get(rt->rtr_req.rtr_family);
+    index = rt_to_index(rt, level);
+
+    if (rt->rtr_req.rtr_prefix_len > ip_bkt_info[level].bi_pfx_len) {
+        limit = ip_bkt_info[level].bi_size;
+    } else {
+        limit = (1 <<
+                (ip_bkt_info[level].bi_pfx_len - rt->rtr_req.rtr_prefix_len));
+    }
+
+    /*
+     * ideally, we would have just followed the calculated index to the
+     * bottom of the tree and returned. however, what happens when the
+     * bottom of the tree is populated with a more specific route? for
+     * e.g.: we are searching for 1.1.0.0/16, but we also have a more
+     * specific route for 1.1.0.0/24. So, to get around that case, we
+     * need to loop the whole bucket, searching for a prefix length match.
+     *
+     * So what happens if all of the prefixes below have a more specific
+     * route. For e.g.: 1.1.0, 1.1.1, 1.1.2, ... 1.1.255. While there are
+     * no practical applications of such a route, for correctness, in such
+     * a case, we loop around the current bucket: i.e. in this case, we will
+     * loop around the bucket that holds 1.1/16. Maybe 1.2/16 was inherited
+     * from a lesser specific prefix and hence a match.
+     */
+    for (i = 0; i < ip_bkt_info[level].bi_size; i++) {
+        ent = index_to_entry(bkt, (index + i) % ip_bkt_info[level].bi_size);
+        ptr = ent->entry_long_i;
+        if (PTR_IS_NEXTHOP(ptr)) {
+            if (i >= limit) {
+                if (ent->entry_prefix_len >= rt->rtr_req.rtr_prefix_len)
+                    continue;
+            }
+
+            if (ent->entry_prefix_len > rt->rtr_req.rtr_prefix_len)
+                continue;
+
+            rt->rtr_req.rtr_label_flags = ent->entry_label_flags;
+            rt->rtr_req.rtr_label = ent->entry_label;
+            rt->rtr_req.rtr_prefix_len = ent->entry_prefix_len;
+            rt->rtr_req.rtr_index = ent->entry_bridge_index;
+            ret_nh = PTR_TO_NEXTHOP(ptr);
+            rt->rtr_nh = ret_nh;
+            break;
+        } else {
+            bkt = PTR_TO_BUCKET(ptr);
+            ret_nh = __mtrie_lookup(rt, bkt, level + 1);
+            if (ret_nh)
+                break;
+        }
+    }
+
+    return ret_nh;
+}
+
 /*
  * longest prefix match. go down the tree till you encounter a next-hop.
  * if no nexthop, there is something wrong with the tree which was built.
@@ -883,36 +952,22 @@ mtrie_stats_dump(struct vr_rtable *rtable, vr_vrf_stats_req *req)
 static struct vr_nexthop *
 mtrie_lookup(unsigned int vrf_id, struct vr_route_req *rt)
 {
-    unsigned int        level, index;
-    unsigned long       ptr;
-    struct ip_mtrie   *table;
-    struct ip_bucket  *bkt;
+    unsigned int level = 0;
+    unsigned long ptr;
+
+    struct ip_mtrie *table;
+    struct ip_bucket *bkt;
     struct ip_bucket_entry *ent;
     struct vr_nexthop *default_nh, *ret_nh;
 
     default_nh = ip4_default_nh;
-
-    /* we do not support any thing other than /32 route lookup */
-    if ((rt->rtr_req.rtr_family == AF_INET) && 
-        (rt->rtr_req.rtr_prefix_len != IP4_PREFIX_LEN)) {
-        rt->rtr_nh = default_nh;
-        return default_nh;
-    }
-
-    if ((rt->rtr_req.rtr_family == AF_INET6) && 
-        (rt->rtr_req.rtr_prefix_len != IP6_PREFIX_LEN)) {
-        rt->rtr_nh = default_nh;
-        return default_nh;
-    }
-
     table = vrfid_to_mtrie(vrf_id, rt->rtr_req.rtr_family);
     if (!table) {
         rt->rtr_nh = default_nh;
         return default_nh;
     }
 
     ent = &table->root;
-
     ptr = ent->entry_long_i;
     if (!ptr) {
         rt->rtr_nh = default_nh;
@@ -935,30 +990,16 @@ mtrie_lookup(unsigned int vrf_id, struct vr_route_req *rt)
         return default_nh;
     }
 
-    for (level = 0; level < ip_bkt_get_max_level(rt->rtr_req.rtr_family); level++) {
-        index = rt_to_index(rt, level);
-        ent = index_to_entry(bkt, index);
-        ptr = ent->entry_long_i;
-        if (PTR_IS_NEXTHOP(ptr)) {
-            rt->rtr_req.rtr_label_flags = ent->entry_label_flags;
-            rt->rtr_req.rtr_label = ent->entry_label;
-            rt->rtr_req.rtr_prefix_len = ent->entry_prefix_len;
-            rt->rtr_req.rtr_index = ent->entry_bridge_index;
-            ret_nh = PTR_TO_NEXTHOP(ptr);
-            rt->rtr_nh = ret_nh;
-            return ret_nh;
-        }
-
-        bkt = PTR_TO_BUCKET(ptr);
-    }
-
-    /* no nexthop; assert */
-    ASSERT(0);
+    ret_nh = __mtrie_lookup(rt, bkt, level);
+    if (!ret_nh)
+        ret_nh = default_nh;
 
     rt->rtr_nh = ret_nh;
-    return NULL;
+
+    return ret_nh;
 }
 
+
 /*
  * adds a route to the corresponding vrf table. returns 0 on
  * success and non-zero otherwise
@@ -1012,12 +1053,29 @@ static int
 mtrie_get(unsigned int vrf_id, struct vr_route_req *rt)
 {
     struct vr_nexthop *nh;
+    struct vr_route_req breq;
+    vr_route_req *req = &rt->rtr_req;
 
     nh = mtrie_lookup(vrf_id, rt);
     if (nh)
-        rt->rtr_req.rtr_nh_id = nh->nh_id;
+        req->rtr_nh_id = nh->nh_id;
     else
-        rt->rtr_req.rtr_nh_id = -1;
+        req->rtr_nh_id = -1;
+
+    if (req->rtr_index != VR_BE_INVALID_INDEX) {
+        req->rtr_mac = vr_zalloc(VR_ETHER_ALEN, VR_ROUTE_REQ_MAC_OBJECT);
+        req->rtr_mac_size = VR_ETHER_ALEN;
+
+        breq.rtr_req.rtr_mac = req->rtr_mac;
+        breq.rtr_req.rtr_index = req->rtr_index;
+        breq.rtr_req.rtr_mac_size = VR_ETHER_ALEN;
+        vr_bridge_lookup(req->rtr_vrf_id, &breq);
+
+    } else {
+        req->rtr_mac_size = 0;
+        req->rtr_mac = NULL;
+    }
+
     return 0;
 }
 

dp-core/vr_route.c

@@ -119,11 +119,22 @@ vr_route_add(vr_route_req *req)
 int
 vr_route_get(vr_route_req *req)
 {
-    struct vr_route_req vr_req;
-    struct vrouter *router;
     int ret = 0;
     uint32_t rt_prefix[4];
-	struct vr_rtable *rtable;
+    bool mac_mem_free = false;
+
+    struct vr_route_req vr_req;
+    struct vrouter *router;
+	struct vr_rtable *rtable = NULL;
+
+    if (!req->rtr_mac)
+        mac_mem_free = true;
+
+    if ((req->rtr_family != AF_INET) && (req->rtr_family != AF_INET6) &&
+            (req->rtr_family != AF_BRIDGE)) {
+        ret = -EINVAL;
+        goto generate_response;
+    }
 
     vr_req.rtr_req = *req;
 
@@ -140,8 +151,12 @@ vr_route_get(vr_route_req *req)
         ret = -ENOENT;
         goto generate_response;
     } else {
+        if ((req->rtr_family == AF_INET) || (req->rtr_family == AF_INET6)) {
+            rtable = router->vr_inet_rtable;
+        } else if (req->rtr_family == AF_BRIDGE) {
+            rtable = router->vr_bridge_rtable;
+        }
 
-        rtable = router->vr_inet_rtable;
         if (!rtable) {
             ret = -ENOENT;
             goto generate_response;
@@ -152,6 +167,11 @@ vr_route_get(vr_route_req *req)
 
 generate_response:
     vr_message_response(VR_ROUTE_OBJECT_ID, ret ? NULL : &vr_req, ret);
+    if (mac_mem_free && vr_req.rtr_req.rtr_mac) {
+        vr_free(vr_req.rtr_req.rtr_mac, VR_ROUTE_REQ_MAC_OBJECT);
+        vr_req.rtr_req.rtr_mac = NULL;
+    }
+
     return ret;
 }
 

include/nl_util.h

@@ -110,6 +110,10 @@ extern void nl_build_attr(struct nl_client *cl, int len, int attr);
 extern int vrouter_get_family_id(struct nl_client *cl);
 extern int get_vrouter_pid(void);
 
+extern char *vr_extract_token(char *, char);
+extern bool vr_valid_ipv6_address(const char *);
+extern bool vr_valid_ipv4_address(const char *);
+
 extern int vr_recvmsg(struct nl_client *cl, bool dump);
 extern int vr_sendmsg(struct nl_client *, void *, char *);
 extern struct nl_client *vr_get_nl_client(unsigned int);
@@ -156,6 +160,8 @@ extern int vr_send_nexthop_add(struct nl_client *, unsigned int,
 
 extern int vr_send_route_dump(struct nl_client *, unsigned int, unsigned int,
         unsigned int, uint8_t *, unsigned int);
+extern int vr_send_route_get(struct nl_client *, unsigned int, unsigned int,
+        unsigned int family, uint8_t *, unsigned int, uint8_t *);
 extern int vr_send_route_delete(struct nl_client *, unsigned int, unsigned int,
         unsigned int family, uint8_t *, unsigned int, unsigned int,
         int, uint8_t *, uint32_t, unsigned ints);

include/vrouter.h

@@ -267,7 +267,6 @@ struct vrouter {
     unsigned int vr_max_nexthops;
     struct vr_btable *vr_nexthops;
     struct vr_rtable *vr_inet_rtable;
-    struct vr_rtable *vr_inet6_rtable;
     struct vr_rtable *vr_inet_mcast_rtable;
     struct vr_rtable *vr_bridge_rtable;