4 files changed, 61 insertions, 0 deletions
diff --git a/vnet/vnet/ip/ip4.h b/vnet/vnet/ip/ip4.h
index 5c530b74952..b14541eb2ef 100644
--- a/vnet/vnet/ip/ip4.h
+++ b/vnet/vnet/ip/ip4.h
@@ -293,6 +293,28 @@ typedef struct {
   u32 n_add_adj;
 } ip4_add_del_route_args_t;
 
+/**
+ * \brief Get or create an IPv4 fib.
+ *
+ * Get or create an IPv4 fib with the provided fib ID or index.
+ * The fib ID is a possibly-sparse user-defined value while
+ * the fib index defines the position of the fib in the fib vector.
+ *
+ * \param im
+ *      ip4_main pointer.
+ * \param table_index_or_id
+ *      The table index if \c IP4_ROUTE_FLAG_FIB_INDEX bit is set in \p flags.
+ *      Otherwise, when set to \c ~0, an arbitrary and unused fib ID is picked
+ *      and can be retrieved with \c ret->table_id.
+ *      Otherwise, the fib ID to be used to retrieve or create the desired fib.
+ * \param flags
+ *      Indicates whether \p table_index_or_id is the fib index or ID.
+ *      When the bit \c IP4_ROUTE_FLAG_FIB_INDEX is set, \p table_index_or_id
+ *      is considered as the fib index, and the fib ID otherwise.
+ * \returns A pointer to the retrieved or created fib.
+ *
+ * \remark When getting a fib with the fib index, the fib MUST already exist.
+ */
 ip4_fib_t *
 find_ip4_fib_by_table_index_or_id (ip4_main_t * im, 
                                    u32 table_index_or_id, u32 flags);
diff --git a/vnet/vnet/ip/ip4_forward.c b/vnet/vnet/ip/ip4_forward.c
index a50664cc662..a84b83bc225 100644
--- a/vnet/vnet/ip/ip4_forward.c
+++ b/vnet/vnet/ip/ip4_forward.c
@@ -103,6 +103,14 @@ find_ip4_fib_by_table_index_or_id (ip4_main_t * im,
   fib_index = table_index_or_id;
   if (! (flags & IP4_ROUTE_FLAG_FIB_INDEX))
     {
+      if (table_index_or_id == ~0) {
+        table_index_or_id = 0;
+        while ((p = hash_get (im->fib_index_by_table_id, table_index_or_id))) {
+          table_index_or_id++;
+        }
+        return create_fib_with_table_id (im, table_index_or_id);
+      }
+
       p = hash_get (im->fib_index_by_table_id, table_index_or_id);
       if (! p)
 	return create_fib_with_table_id (im, table_index_or_id);
diff --git a/vnet/vnet/ip/ip6.h b/vnet/vnet/ip/ip6.h
index b1043595c29..4d0e8564aa2 100644
--- a/vnet/vnet/ip/ip6.h
+++ b/vnet/vnet/ip/ip6.h
@@ -204,6 +204,29 @@ typedef union {
 u32 ip6_fib_lookup (ip6_main_t * im, u32 sw_if_index, ip6_address_t * dst);
 u32 ip6_fib_lookup_with_table (ip6_main_t * im, u32 fib_index, 
                                ip6_address_t * dst);
+
+/**
+ * \brief Get or create an IPv6 fib.
+ *
+ * Get or create an IPv6 fib with the provided fib ID or index.
+ * The fib ID is a possibly-sparse user-defined value while
+ * the fib index defines the position of the fib in the fib vector.
+ *
+ * \param im
+ *      ip6_main pointer.
+ * \param table_index_or_id
+ *      The table index if \c IP6_ROUTE_FLAG_FIB_INDEX bit is set in \p flags.
+ *      Otherwise, when set to \c ~0, an arbitrary and unused fib ID is picked
+ *      and can be retrieved with \c ret->table_id.
+ *      Otherwise, it is the fib ID to be used to retrieve or create the desired fib.
+ * \param flags
+ *      Indicates whether \p table_index_or_id is the fib index or ID.
+ *      When the bit \c IP6_ROUTE_FLAG_FIB_INDEX is set, \p table_index_or_id
+ *      is considered as the fib index, and the fib ID otherwise.
+ * \return A pointer to the retrieved or created fib.
+ *
+ * \remark When getting a fib with the fib index, the fib MUST already exist.
+ */
 ip6_fib_t * find_ip6_fib_by_table_index_or_id (ip6_main_t * im, 
                                                u32 table_index_or_id, 
                                                u32 flags);
diff --git a/vnet/vnet/ip/ip6_forward.c b/vnet/vnet/ip/ip6_forward.c
index e82e0a6b472..a136da3e142 100644
--- a/vnet/vnet/ip/ip6_forward.c
+++ b/vnet/vnet/ip/ip6_forward.c
@@ -189,6 +189,14 @@ find_ip6_fib_by_table_index_or_id (ip6_main_t * im, u32 table_index_or_id, u32 f
   fib_index = table_index_or_id;
   if (! (flags & IP6_ROUTE_FLAG_FIB_INDEX))
     {
+      if (table_index_or_id == ~0) {
+        table_index_or_id = 0;
+        while (hash_get (im->fib_index_by_table_id, table_index_or_id)) {
+          table_index_or_id++;
+        }
+        return create_fib_with_table_id (im, table_index_or_id);
+      }
+
       p = hash_get (im->fib_index_by_table_id, table_index_or_id);
       if (! p)
 	return create_fib_with_table_id (im, table_index_or_id);