dpdk: format_dpdk_device_name cleanup

[vpp.git] / src / plugins / cdp / cdp_input.c

diff --git a/src/plugins/cdp/cdp_input.c b/src/plugins/cdp/cdp_input.c
index fa993b8..dd3619c 100644 (file)
--- a/src/plugins/cdp/cdp_input.c
+++ b/src/plugins/cdp/cdp_input.c
@@ -250,7 +250,7 @@ process_cdp_hdr (cdp_main_t * cm, cdp_neighbor_t * n, cdp_hdr_t * h)
 static int
 cdp_packet_scan (cdp_main_t * cm, cdp_neighbor_t * n)
 {
-  u8 *cur = n->last_rx_pkt;
+  u8 *end, *cur = n->last_rx_pkt;
   cdp_hdr_t *h;
   cdp_tlv_t *tlv;
   cdp_error_t e = CDP_ERROR_NONE;
@@ -269,24 +269,42 @@ cdp_packet_scan (cdp_main_t * cm, cdp_neighbor_t * n)
   if (e)
     return e;
 
+  // there are no tlvs
+  if (vec_len (n->last_rx_pkt) <= 0)
+    return CDP_ERROR_BAD_TLV;
+
   cur = (u8 *) (h + 1);
+  end = n->last_rx_pkt + vec_len (n->last_rx_pkt) - 1;
 
-  while (cur < n->last_rx_pkt + vec_len (n->last_rx_pkt) - 1)
+  // look ahead 4 bytes (u16 tlv->t + u16 tlv->l)
+  while (cur + 3 <= end)
     {
       tlv = (cdp_tlv_t *) cur;
       tlv->t = ntohs (tlv->t);
       tlv->l = ntohs (tlv->l);
-      if (tlv->t >= ARRAY_LEN (tlv_handlers))
-       return CDP_ERROR_BAD_TLV;
-      handler = &tlv_handlers[tlv->t];
-      fp = handler->process;
-      e = (*fp) (cm, n, tlv);
-      if (e)
-       return e;
-      /* tlv length includes (t, l) */
+
+      /* tlv length includes t, l and v */
       cur += tlv->l;
+      if ((cur - 1) > end)
+       return CDP_ERROR_BAD_TLV;
+      /*
+       * Only process known TLVs. In practice, certain
+       * devices send tlv->t = 0xFF, perhaps as an EOF of sorts.
+       */
+      if (tlv->t < ARRAY_LEN (tlv_handlers))
+       {
+         handler = &tlv_handlers[tlv->t];
+         fp = handler->process;
+         e = (*fp) (cm, n, tlv);
+         if (e)
+           return e;
+       }
     }
 
+  // did not process all tlvs or none tlv processed
+  if ((cur - 1) != end)
+    return CDP_ERROR_BAD_TLV;
+
   return CDP_ERROR_NONE;
 }
 
@@ -310,7 +328,7 @@ cdp_input (vlib_main_t * vm, vlib_buffer_t * b0, u32 bi0)
   if (p == 0)
     {
       pool_get (cm->neighbors, n);
-      memset (n, 0, sizeof (*n));
+      clib_memset (n, 0, sizeof (*n));
       n->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
       n->packet_template_index = (u8) ~ 0;
       hash_set (cm->neighbor_by_sw_if_index, n->sw_if_index,