igmp: accept packets that have more on the wire data than IGMP reports.

[vpp.git] / src / plugins / igmp / igmp_input.c

diff --git a/src/plugins/igmp/igmp_input.c b/src/plugins/igmp/igmp_input.c
index a49790f..1858a1b 100644 (file)
--- a/src/plugins/igmp/igmp_input.c
+++ b/src/plugins/igmp/igmp_input.c
@@ -276,6 +276,7 @@ igmp_parse_query (vlib_main_t * vm, vlib_node_runtime_t * node,
          b = vlib_get_buffer (vm, bi);
          igmp = vlib_buffer_get_current (b);
          ASSERT (igmp->header.type == IGMP_TYPE_membership_query);
+         len = igmp_membership_query_v3_length (igmp);
 
          if (node->flags & VLIB_NODE_FLAG_TRACE)
            {
@@ -283,17 +284,17 @@ igmp_parse_query (vlib_main_t * vm, vlib_node_runtime_t * node,
              tr = vlib_add_trace (vm, node, b, sizeof (*tr));
              tr->next_index = next;
              tr->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
-             tr->len = vlib_buffer_length_in_chain (vm, b);
+             tr->len = len;
              clib_memcpy_fast (tr->packet_data, vlib_buffer_get_current (b),
                                sizeof (tr->packet_data));
            }
-         len = igmp_membership_query_v3_length (igmp);
 
          /*
-          * validate that the length on the packet on the wire
-          * corresponds to the length on the calculated v3 query
+          * validate that the length on the packet on the wire  corresponds
+          * to at least the length of the calculated v3 query.
+          * If there's extra, then it will be ignored.
           */
-         if (vlib_buffer_length_in_chain (vm, b) == len)
+         if (vlib_buffer_length_in_chain (vm, b) >= len)
            {
              /*
               * copy the contents of the query, and the interface, over
@@ -309,8 +310,8 @@ igmp_parse_query (vlib_main_t * vm, vlib_node_runtime_t * node,
          else
            {
              /*
-              * else a packet that is reporting more or less sources
-              * than it really has, bin it
+              * else a packet that is reporting more sources than it really
+              * has; bin it
               */
              b->error = node->errors[IGMP_ERROR_BAD_LENGTH];
            }
@@ -394,6 +395,7 @@ igmp_parse_report (vlib_main_t * vm, vlib_node_runtime_t * node,
              igmp_input_trace_t *tr;
              tr = vlib_add_trace (vm, node, b, sizeof (*tr));
              tr->next_index = next;
+             tr->len = len;
              tr->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
              clib_memcpy_fast (tr->packet_data, vlib_buffer_get_current (b),
                                sizeof (tr->packet_data));
@@ -403,7 +405,7 @@ igmp_parse_report (vlib_main_t * vm, vlib_node_runtime_t * node,
           * validate that the length on the packet on the wire
           * corresponds to the length on the calculated v3 query
           */
-         if (vlib_buffer_length_in_chain (vm, b) == len)
+         if (vlib_buffer_length_in_chain (vm, b) >= len)
            {
              /*
               * copy the contents of the query, and the interface, over
@@ -416,11 +418,15 @@ igmp_parse_report (vlib_main_t * vm, vlib_node_runtime_t * node,
              vl_api_rpc_call_main_thread (igmp_handle_report,
                                           (u8 *) args, sizeof (*args) + len);
            }
-         /*
-          * else
-          *   this is a packet with more groups/sources than the
-          *   header reports. bin it
-          */
+         else
+           {
+             /*
+              * this is a packet with more groups/sources than the
+              * header reports. bin it
+              */
+             b->error = node->errors[IGMP_ERROR_BAD_LENGTH];
+           }
+
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
                                           n_left_to_next, bi, next);
        }