SCTP: DATA chunk padding fix and hardening

[vpp.git] / src / vnet / sctp / sctp_input.c

diff --git a/src/vnet/sctp/sctp_input.c b/src/vnet/sctp/sctp_input.c
index 7c753a2..e548707 100644 (file)
--- a/src/vnet/sctp/sctp_input.c
+++ b/src/vnet/sctp/sctp_input.c
@@ -492,7 +492,6 @@ sctp_handle_init_ack (sctp_header_t * sctp_hdr,
 {
   sctp_init_ack_chunk_t *init_ack_chunk =
     (sctp_init_ack_chunk_t *) (sctp_hdr);
-  sctp_state_cookie_param_t state_cookie;
 
   char hostname[FQDN_MAX_LENGTH];
 
@@ -569,8 +568,9 @@ sctp_handle_init_ack (sctp_header_t * sctp_hdr,
                sctp_state_cookie_param_t *state_cookie_param =
                  (sctp_state_cookie_param_t *) opt_params_hdr;
 
-               clib_memcpy (&state_cookie, state_cookie_param,
+               clib_memcpy (&(sctp_conn->cookie_param), state_cookie_param,
                             sizeof (sctp_state_cookie_param_t));
+
                break;
              }
            case SCTP_HOSTNAME_ADDRESS_TYPE:
@@ -596,9 +596,6 @@ sctp_handle_init_ack (sctp_header_t * sctp_hdr,
        }
     }
 
-  clib_memcpy (&(sctp_conn->cookie_param), &state_cookie,
-              sizeof (sctp_state_cookie_param_t));
-
   sctp_prepare_cookie_echo_chunk (sctp_conn, idx, b0, 1);
 
   /* Start the T1_COOKIE timer */
@@ -780,7 +777,9 @@ sctp_handle_data (sctp_payload_data_chunk_t * sctp_data_chunk,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_data_chunk->sctp_hdr.verification_tag)
     {
-      return SCTP_ERROR_INVALID_TAG;
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
+      sctp_conn->sub_conn[idx].enqueue_state = SCTP_ERROR_INVALID_TAG;
+      return sctp_conn->sub_conn[idx].enqueue_state;
     }
 
   vnet_buffer (b)->sctp.sid = sctp_data_chunk->stream_id;
@@ -789,8 +788,27 @@ sctp_handle_data (sctp_payload_data_chunk_t * sctp_data_chunk,
   u32 tsn = clib_net_to_host_u32 (sctp_data_chunk->tsn);
 
   vlib_buffer_advance (b, vnet_buffer (b)->sctp.data_offset);
+  u32 chunk_len = vnet_sctp_get_chunk_length (&sctp_data_chunk->chunk_hdr) -
+    (sizeof (sctp_payload_data_chunk_t) - sizeof (sctp_header_t));
+
+  ASSERT (vnet_buffer (b)->sctp.data_len);
+  ASSERT (chunk_len);
+
+  /* Padding was added: see RFC 4096 section 3.3.1 */
+  if (vnet_buffer (b)->sctp.data_len > chunk_len)
+    {
+      /* Let's change the data_len to the right amount calculated here now.
+       * We cannot do that in the generic sctp46_input_dispatcher node since
+       * that is common to all CHUNKS handling.
+       */
+      vnet_buffer (b)->sctp.data_len = chunk_len;
+      /* We need to change b->current_length so that downstream calls to
+       * session_enqueue_stream_connection (called by sctp_session_enqueue_data)
+       * push the correct amount of data to be enqueued.
+       */
+      b->current_length = chunk_len;
+    }
   n_data_bytes = vnet_buffer (b)->sctp.data_len;
-  ASSERT (n_data_bytes);
 
   sctp_is_connection_gapping (sctp_conn, tsn, &is_gapping);
 
@@ -854,7 +872,7 @@ sctp_handle_cookie_echo (sctp_header_t * sctp_hdr,
                         sctp_connection_t * sctp_conn, u8 idx,
                         vlib_buffer_t * b0, u16 * next0)
 {
-  u32 now = sctp_time_now ();
+  u64 now = sctp_time_now ();
 
   sctp_cookie_echo_chunk_t *cookie_echo =
     (sctp_cookie_echo_chunk_t *) sctp_hdr;
@@ -862,15 +880,17 @@ sctp_handle_cookie_echo (sctp_header_t * sctp_hdr,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hdr->verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
   sctp_calculate_rto (sctp_conn, idx);
 
-  u32 creation_time =
-    clib_net_to_host_u32 (cookie_echo->cookie.creation_time);
-  u32 cookie_lifespan =
+  u64 creation_time =
+    clib_net_to_host_u64 (cookie_echo->cookie.creation_time);
+  u64 cookie_lifespan =
     clib_net_to_host_u32 (cookie_echo->cookie.cookie_lifespan);
+
   if (now > creation_time + cookie_lifespan)
     {
       SCTP_DBG ("now (%u) > creation_time (%u) + cookie_lifespan (%u)",
@@ -903,6 +923,7 @@ sctp_handle_cookie_ack (sctp_header_t * sctp_hdr,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hdr->verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1063,7 +1084,7 @@ sctp46_rcv_phase_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
               * hence we should never get to the "default" case below.
               */
            default:
-             error0 = SCTP_ERROR_UNKOWN_CHUNK;
+             error0 = SCTP_ERROR_UNKNOWN_CHUNK;
              next0 = sctp_next_drop (is_ip4);
              goto drop;
            }
@@ -1183,6 +1204,7 @@ sctp_handle_shutdown (sctp_header_t * sctp_hdr,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hdr->verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1223,6 +1245,7 @@ sctp_handle_shutdown_ack (sctp_header_t * sctp_hdr,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hdr->verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1259,6 +1282,7 @@ sctp_handle_shutdown_complete (sctp_header_t * sctp_hdr,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hdr->verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1403,7 +1427,7 @@ sctp46_shutdown_phase_inline (vlib_main_t * vm,
               * hence we should never get to the "default" case below.
               */
            default:
-             error0 = SCTP_ERROR_UNKOWN_CHUNK;
+             error0 = SCTP_ERROR_UNKNOWN_CHUNK;
              next0 = sctp_next_drop (is_ip4);
              goto drop;
            }
@@ -1519,6 +1543,7 @@ sctp_handle_sack (sctp_selective_ack_chunk_t * sack_chunk,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sack_chunk->sctp_hdr.verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1557,6 +1582,7 @@ sctp_handle_heartbeat (sctp_hb_req_chunk_t * sctp_hb_chunk,
   /* Check that the LOCALLY generated tag is being used by the REMOTE peer as the verification tag */
   if (sctp_conn->local_tag != sctp_hb_chunk->sctp_hdr.verification_tag)
     {
+      *next0 = sctp_next_drop (sctp_conn->sub_conn[idx].c_is_ip4);
       return SCTP_ERROR_INVALID_TAG;
     }
 
@@ -1712,7 +1738,7 @@ sctp46_listen_process_inline (vlib_main_t * vm,
                 child_conn->sub_conn[SCTP_PRIMARY_PATH_IDX].
                 connection.c_index, sctp_chunk_to_string (chunk_type));
 
-             error0 = SCTP_ERROR_UNKOWN_CHUNK;
+             error0 = SCTP_ERROR_UNKNOWN_CHUNK;
              next0 = sctp_next_drop (is_ip4);
              goto drop;
            }
@@ -1920,7 +1946,7 @@ sctp46_established_phase_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
               * hence we should never get to the "default" case below.
               */
            default:
-             error0 = SCTP_ERROR_UNKOWN_CHUNK;
+             error0 = SCTP_ERROR_UNKNOWN_CHUNK;
              next0 = sctp_next_drop (is_ip4);
              goto done;
            }
@@ -2191,7 +2217,7 @@ sctp46_input_dispatcher (vlib_main_t * vm, vlib_node_runtime_t * node,
              sctp_prepare_operation_error (sctp_conn, SCTP_PRIMARY_PATH_IDX,
                                            b0, UNRECOGNIZED_CHUNK_TYPE);
 
-             error0 = SCTP_ERROR_UNKOWN_CHUNK;
+             error0 = SCTP_ERROR_UNKNOWN_CHUNK;
              next0 = sctp_next_output (is_ip4);
              goto done;
            }