SR-MPLS: MPLS table checks (VPP-1422)

[vpp.git] / src / vnet / srmpls / sr_mpls_policy.c

diff --git a/src/vnet/srmpls/sr_mpls_policy.c b/src/vnet/srmpls/sr_mpls_policy.c
index 4a56324..f94a8e9 100755 (executable)
--- a/src/vnet/srmpls/sr_mpls_policy.c
+++ b/src/vnet/srmpls/sr_mpls_policy.c
@@ -61,6 +61,7 @@ create_sl (mpls_sr_policy_t * sr_policy, mpls_label_t * sl, u32 weight)
 {
   mpls_sr_main_t *sm = &sr_mpls_main;
   mpls_sr_sl_t *segment_list;
+  u32 ii;
 
   pool_get (sm->sid_lists, segment_list);
   memset (segment_list, 0, sizeof (*segment_list));
@@ -85,20 +86,37 @@ create_sl (mpls_sr_policy_t * sr_policy, mpls_label_t * sl, u32 weight)
       .frp_local_label = sl[0],
     };
 
-    vec_add (path.frp_label_stack, sl + 1, vec_len (sl) - 1);
+    if (vec_len (sl) > 1)
+      {
+       vec_validate (path.frp_label_stack, vec_len (sl) - 2);
+       for (ii = 1; ii < vec_len (sl); ii++)
+         {
+           path.frp_label_stack[ii - 1].fml_value = sl[ii];
+         }
+      }
+    else
+      {
+       /*
+        * add an impliciet NULL label to allow non-eos recursion
+        */
+       fib_mpls_label_t lbl = {
+         .fml_value = MPLS_IETF_IMPLICIT_NULL_LABEL,
+       };
+       vec_add1 (path.frp_label_stack, lbl);
+      }
 
     fib_route_path_t *paths = NULL;
     vec_add1 (paths, path);
 
-               /* *INDENT-OFF* */
-               fib_prefix_t    pfx = {
-                       .fp_len = 21,
-                       .fp_proto = FIB_PROTOCOL_MPLS,
-                       .fp_label = sr_policy->bsid,
-                       .fp_eos = eos,
-                       .fp_payload_proto = DPO_PROTO_MPLS,
-               };
-               /* *INDENT-ON* */
+    /* *INDENT-OFF* */
+    fib_prefix_t pfx = {
+        .fp_len = 21,
+        .fp_proto = FIB_PROTOCOL_MPLS,
+        .fp_label = sr_policy->bsid,
+        .fp_eos = eos,
+        .fp_payload_proto = DPO_PROTO_MPLS,
+    };
+    /* *INDENT-ON* */
 
     fib_table_entry_path_add2 (0,
                               &pfx,
@@ -141,6 +159,10 @@ sr_mpls_policy_add (mpls_label_t bsid, mpls_label_t * segments,
   if (!sm->sr_policies_index_hash)
     sm->sr_policies_index_hash = hash_create (0, sizeof (mpls_label_t));
 
+  /* MPLS SR policies cannot be created unless the MPLS table is present */
+  if (~0 == fib_table_find (FIB_PROTOCOL_MPLS, MPLS_FIB_DEFAULT_TABLE_ID))
+    return (VNET_API_ERROR_NO_SUCH_TABLE);
+
   /* Search for existing keys (BSID) */
   p = hash_get (sm->sr_policies_index_hash, bsid);
   if (p)
@@ -151,6 +173,13 @@ sr_mpls_policy_add (mpls_label_t bsid, mpls_label_t * segments,
   /* Add an SR policy object */
   pool_get (sm->sr_policies, sr_policy);
   memset (sr_policy, 0, sizeof (*sr_policy));
+
+  /* the first policy needs to lock the MPLS table so it doesn't
+   * disappear with policies in it */
+  if (1 == pool_elts (sm->sr_policies))
+    fib_table_find_or_create_and_lock (FIB_PROTOCOL_MPLS,
+                                      MPLS_FIB_DEFAULT_TABLE_ID,
+                                      FIB_SOURCE_SR);
   sr_policy->bsid = bsid;
   sr_policy->type = behavior;
   sr_policy->endpoint_type = 0;
@@ -243,6 +272,10 @@ sr_mpls_policy_del (mpls_label_t bsid)
   hash_unset (sm->sr_policies_index_hash, sr_policy->bsid);
   pool_put (sm->sr_policies, sr_policy);
 
+  if (0 == pool_elts (sm->sr_policies))
+    fib_table_unlock (MPLS_FIB_DEFAULT_TABLE_ID,
+                     FIB_PROTOCOL_MPLS, FIB_SOURCE_SR);
+
   return 0;
 }
 
@@ -484,6 +517,7 @@ sr_mpls_policy_command_fn (vlib_main_t * vm, unformat_input_t * input,
       rv = sr_mpls_policy_add (bsid, segments,
                               (is_spray ? SR_POLICY_TYPE_SPRAY :
                                SR_POLICY_TYPE_DEFAULT), weight);
+      vec_free (segments);
     }
   else if (is_del)
     rv = sr_mpls_policy_del (bsid);
@@ -498,6 +532,7 @@ sr_mpls_policy_command_fn (vlib_main_t * vm, unformat_input_t * input,
       if (operation == 3 && weight == (u32) ~ 0)
        return clib_error_return (0, "No new weight for the SL specified");
       rv = sr_mpls_policy_mod (bsid, operation, segments, sl_index, weight);
+      vec_free (segments);
     }
   switch (rv)
     {
@@ -525,6 +560,8 @@ sr_mpls_policy_command_fn (vlib_main_t * vm, unformat_input_t * input,
       return clib_error_return (0,
                                "Could not modify the segment list. "
                                "The given SL is not associated with such SR policy.");
+    case VNET_API_ERROR_NO_SUCH_TABLE:
+      return clib_error_return (0, "the Default MPLS table is not present");
     default:
       return clib_error_return (0, "BUG: sr policy returns %d", rv);
     }
@@ -661,6 +698,10 @@ sr_mpls_policy_assign_endpoint_color (mpls_label_t bsid,
       old_value =
        mhash_get ((mhash_t *) endpoint_table, &sr_policy->endpoint);
 
+      /* CID 180995 This should never be NULL unless the two hash tables
+       * get out of sync */
+      ASSERT (old_value != NULL);
+
       fib_prefix_t pfx = { 0 };
       pfx.fp_proto = FIB_PROTOCOL_MPLS;
       pfx.fp_len = 21;