ip: unlock_fib on if delete

On interface delete we were not removing
the lock taken by a previous ip_table_bind()
call thus preventing the VRFs to be removed.

Type: fix

Change-Id: I11abbb51a09b45cd3390b23d5d601d029c5ea485
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

4 files changed, 99 insertions, 54 deletions

diff --git a/src/vnet/interface_api.c b/src/vnet/interface_api.c
index bbb6168df9e..a765c0bbc3d 100644
--- a/src/vnet/interface_api.c
+++ b/src/vnet/interface_api.c
@@ -470,41 +470,17 @@ vl_api_sw_interface_set_table_t_handler (vl_api_sw_interface_set_table_t * mp)
   REPLY_MACRO (VL_API_SW_INTERFACE_SET_TABLE_REPLY);
 }
 
-int
-ip_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 table_id)
+void
+fib_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 fib_index)
 {
-  CLIB_UNUSED (ip_interface_address_t * ia);
-  u32 fib_index, mfib_index;
+  u32 table_id;
 
-  /*
-   * This if table does not exist = error is what we want in the end.
-   */
-  fib_index = fib_table_find (fproto, table_id);
-  mfib_index = mfib_table_find (fproto, table_id);
-
-  if (~0 == fib_index || ~0 == mfib_index)
-    {
-      return (VNET_API_ERROR_NO_SUCH_FIB);
-    }
+  table_id = fib_table_get_table_id (fib_index, fproto);
+  ASSERT (table_id != ~0);
 
   if (FIB_PROTOCOL_IP6 == fproto)
     {
       /*
-       * If the interface already has in IP address, then a change int
-       * VRF is not allowed. The IP address applied must first be removed.
-       * We do not do that automatically here, since VPP has no knowledge
-       * of whether those subnets are valid in the destination VRF.
-       */
-      /* *INDENT-OFF* */
-      foreach_ip_interface_address (&ip6_main.lookup_main,
-				    ia, sw_if_index,
-				    1 /* honor unnumbered */ ,
-      ({
-        return (VNET_API_ERROR_ADDRESS_FOUND_FOR_INTERFACE);
-      }));
-      /* *INDENT-ON* */
-
-      /*
        * tell those that are interested that the binding is changing.
        */
       ip6_table_bind_callback_t *cb;
@@ -518,39 +494,18 @@ ip_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 table_id)
       if (0 != ip6_main.fib_index_by_sw_if_index[sw_if_index])
 	fib_table_unlock (ip6_main.fib_index_by_sw_if_index[sw_if_index],
 			  FIB_PROTOCOL_IP6, FIB_SOURCE_INTERFACE);
-      if (0 != ip6_main.mfib_index_by_sw_if_index[sw_if_index])
-	mfib_table_unlock (ip6_main.mfib_index_by_sw_if_index[sw_if_index],
-			   FIB_PROTOCOL_IP6, MFIB_SOURCE_INTERFACE);
 
       if (0 != table_id)
 	{
 	  /* we need to lock the table now it's inuse */
 	  fib_table_lock (fib_index, FIB_PROTOCOL_IP6, FIB_SOURCE_INTERFACE);
-	  mfib_table_lock (mfib_index, FIB_PROTOCOL_IP6,
-			   MFIB_SOURCE_INTERFACE);
 	}
 
       ip6_main.fib_index_by_sw_if_index[sw_if_index] = fib_index;
-      ip6_main.mfib_index_by_sw_if_index[sw_if_index] = mfib_index;
     }
   else
     {
       /*
-       * If the interface already has in IP address, then a change int
-       * VRF is not allowed. The IP address applied must first be removed.
-       * We do not do that automatically here, since VPP has no knowledge
-       * of whether those subnets are valid in the destination VRF.
-       */
-      /* *INDENT-OFF* */
-      foreach_ip_interface_address (&ip4_main.lookup_main,
-				    ia, sw_if_index,
-				    1 /* honor unnumbered */ ,
-      ({
-        return (VNET_API_ERROR_ADDRESS_FOUND_FOR_INTERFACE);
-      }));
-      /* *INDENT-ON* */
-
-      /*
        * tell those that are interested that the binding is changing.
        */
       ip4_table_bind_callback_t *cb;
@@ -564,23 +519,93 @@ ip_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 table_id)
       if (0 != ip4_main.fib_index_by_sw_if_index[sw_if_index])
 	fib_table_unlock (ip4_main.fib_index_by_sw_if_index[sw_if_index],
 			  FIB_PROTOCOL_IP4, FIB_SOURCE_INTERFACE);
-      if (0 != ip4_main.mfib_index_by_sw_if_index[sw_if_index])
-	mfib_table_unlock (ip4_main.mfib_index_by_sw_if_index[sw_if_index],
-			   FIB_PROTOCOL_IP4, MFIB_SOURCE_INTERFACE);
 
       if (0 != table_id)
 	{
 	  /* we need to lock the table now it's inuse */
 	  fib_index = fib_table_find_or_create_and_lock (
 	    FIB_PROTOCOL_IP4, table_id, FIB_SOURCE_INTERFACE);
+	}
+
+      ip4_main.fib_index_by_sw_if_index[sw_if_index] = fib_index;
+    }
+}
+
+void
+mfib_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 mfib_index)
+{
+  u32 table_id;
+
+  table_id = mfib_table_get_table_id (mfib_index, fproto);
+  ASSERT (table_id != ~0);
+
+  if (FIB_PROTOCOL_IP6 == fproto)
+    {
+      if (0 != ip6_main.mfib_index_by_sw_if_index[sw_if_index])
+	mfib_table_unlock (ip6_main.mfib_index_by_sw_if_index[sw_if_index],
+			   FIB_PROTOCOL_IP6, MFIB_SOURCE_INTERFACE);
 
+      if (0 != table_id)
+	{
+	  /* we need to lock the table now it's inuse */
+	  mfib_table_lock (mfib_index, FIB_PROTOCOL_IP6,
+			   MFIB_SOURCE_INTERFACE);
+	}
+
+      ip6_main.mfib_index_by_sw_if_index[sw_if_index] = mfib_index;
+    }
+  else
+    {
+      if (0 != ip4_main.mfib_index_by_sw_if_index[sw_if_index])
+	mfib_table_unlock (ip4_main.mfib_index_by_sw_if_index[sw_if_index],
+			   FIB_PROTOCOL_IP4, MFIB_SOURCE_INTERFACE);
+
+      if (0 != table_id)
+	{
+	  /* we need to lock the table now it's inuse */
 	  mfib_index = mfib_table_find_or_create_and_lock (
 	    FIB_PROTOCOL_IP4, table_id, MFIB_SOURCE_INTERFACE);
 	}
 
-      ip4_main.fib_index_by_sw_if_index[sw_if_index] = fib_index;
       ip4_main.mfib_index_by_sw_if_index[sw_if_index] = mfib_index;
     }
+}
+
+int
+ip_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 table_id)
+{
+  CLIB_UNUSED (ip_interface_address_t * ia);
+  u32 fib_index, mfib_index;
+
+  /*
+   * This if table does not exist = error is what we want in the end.
+   */
+  fib_index = fib_table_find (fproto, table_id);
+  mfib_index = mfib_table_find (fproto, table_id);
+
+  if (~0 == fib_index || ~0 == mfib_index)
+    {
+      return (VNET_API_ERROR_NO_SUCH_FIB);
+    }
+
+  /*
+   * If the interface already has in IP address, then a change int
+   * VRF is not allowed. The IP address applied must first be removed.
+   * We do not do that automatically here, since VPP has no knowledge
+   * of whether those subnets are valid in the destination VRF.
+   */
+  /* clang-format off */
+  foreach_ip_interface_address (FIB_PROTOCOL_IP6 == fproto ?
+				&ip6_main.lookup_main : &ip4_main.lookup_main,
+				ia, sw_if_index,
+				1 /* honor unnumbered */ ,
+  ({
+    return (VNET_API_ERROR_ADDRESS_FOUND_FOR_INTERFACE);
+  }));
+  /* clang-format on */
+
+  fib_table_bind (fproto, sw_if_index, fib_index);
+  mfib_table_bind (fproto, sw_if_index, mfib_index);
 
   return (0);
 }
diff --git a/src/vnet/ip/ip.h b/src/vnet/ip/ip.h
index 131d6879c14..c2a38016ba5 100644
--- a/src/vnet/ip/ip.h
+++ b/src/vnet/ip/ip.h
@@ -267,6 +267,8 @@ void ip_table_create (fib_protocol_t fproto, u32 table_id, u8 is_api,
 
 void ip_table_delete (fib_protocol_t fproto, u32 table_id, u8 is_api);
 
+void fib_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 fib_index);
+void mfib_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 mfib_index);
 int ip_table_bind (fib_protocol_t fproto, u32 sw_if_index, u32 table_id);
 
 u32 ip_table_get_unused_id (fib_protocol_t fproto);
diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index 58af706e2b2..de8e8e8538f 100644
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -1090,6 +1090,15 @@ ip4_sw_interface_add_del (vnet_main_t * vnm, u32 sw_if_index, u32 is_add)
       }));
       /* *INDENT-ON* */
       ip4_mfib_interface_enable_disable (sw_if_index, 0);
+
+      if (0 != im4->fib_index_by_sw_if_index[sw_if_index])
+	fib_table_bind (FIB_PROTOCOL_IP4, sw_if_index, 0);
+      if (0 != im4->mfib_index_by_sw_if_index[sw_if_index])
+	mfib_table_bind (FIB_PROTOCOL_IP4, sw_if_index, 0);
+
+      /* Erase the lookup tables just in case */
+      im4->fib_index_by_sw_if_index[sw_if_index] = ~0;
+      im4->mfib_index_by_sw_if_index[sw_if_index] = ~0;
     }
 
   vnet_feature_enable_disable ("ip4-unicast", "ip4-not-enabled", sw_if_index,
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index 833ce142999..9ee3d11cef2 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -717,6 +717,15 @@ ip6_sw_interface_add_del (vnet_main_t * vnm, u32 sw_if_index, u32 is_add)
       }));
       /* *INDENT-ON* */
       ip6_mfib_interface_enable_disable (sw_if_index, 0);
+
+      if (0 != im6->fib_index_by_sw_if_index[sw_if_index])
+	fib_table_bind (FIB_PROTOCOL_IP6, sw_if_index, 0);
+      if (0 != im6->mfib_index_by_sw_if_index[sw_if_index])
+	mfib_table_bind (FIB_PROTOCOL_IP6, sw_if_index, 0);
+
+      /* Erase the lookup tables just in case */
+      im6->fib_index_by_sw_if_index[sw_if_index] = ~0;
+      im6->mfib_index_by_sw_if_index[sw_if_index] = ~0;
     }
 
   vnet_feature_enable_disable ("ip6-unicast", "ip6-not-enabled", sw_if_index,