tcp: custom checksum calculations for Ipv4/Ipv6

[vpp.git] / src / vnet / ip / ip6_forward.c

diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index ea13116..47fb57a 100644 (file)
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -1011,11 +1011,10 @@ ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
                                   ip6_header_t * ip0, int *bogus_lengthp)
 {
   ip_csum_t sum0;
-  u16 sum16, payload_length_host_byte_order;
-  u32 i, n_this_buffer, n_bytes_left;
+  u16 payload_length_host_byte_order;
+  u32 i;
   u32 headers_size = sizeof (ip0[0]);
   u8 *data_this_buffer;
-  u8 length_odd;
 
   ASSERT (bogus_lengthp);
   *bogus_lengthp = 0;
@@ -1027,14 +1026,10 @@ ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
 
   for (i = 0; i < ARRAY_LEN (ip0->src_address.as_uword); i++)
     {
-      sum0 = ip_csum_with_carry (sum0,
-                                clib_mem_unaligned (&ip0->
-                                                    src_address.as_uword[i],
-                                                    uword));
-      sum0 =
-       ip_csum_with_carry (sum0,
-                           clib_mem_unaligned (&ip0->dst_address.as_uword[i],
-                                               uword));
+      sum0 = ip_csum_with_carry
+       (sum0, clib_mem_unaligned (&ip0->src_address.as_uword[i], uword));
+      sum0 = ip_csum_with_carry
+       (sum0, clib_mem_unaligned (&ip0->dst_address.as_uword[i], uword));
     }
 
   /* some icmp packets may come with a "router alert" hop-by-hop extension header (e.g., mldv2 packets)
@@ -1056,52 +1051,14 @@ ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
       headers_size += skip_bytes;
     }
 
-  n_bytes_left = n_this_buffer = payload_length_host_byte_order;
-
   if (p0)
-    {
-      u32 n_ip_bytes_this_buffer =
-       p0->current_length - (((u8 *) ip0 - p0->data) - p0->current_data);
-      if (n_this_buffer + headers_size > n_ip_bytes_this_buffer)
-       {
-         n_this_buffer = p0->current_length > headers_size ?
-           n_ip_bytes_this_buffer - headers_size : 0;
-       }
-    }
-
-  while (1)
-    {
-      sum0 = ip_incremental_checksum (sum0, data_this_buffer, n_this_buffer);
-      n_bytes_left -= n_this_buffer;
-      if (n_bytes_left == 0)
-       break;
-
-      ASSERT (p0->flags & VLIB_BUFFER_NEXT_PRESENT);
-      if (!(p0->flags & VLIB_BUFFER_NEXT_PRESENT))
-       {
-         *bogus_lengthp = 1;
-         return 0xfefe;
-       }
-
-      length_odd = (n_this_buffer & 1);
-
-      p0 = vlib_get_buffer (vm, p0->next_buffer);
-      data_this_buffer = vlib_buffer_get_current (p0);
-      n_this_buffer = clib_min (p0->current_length, n_bytes_left);
-
-      if (PREDICT_FALSE (length_odd))
-       {
-         /* Prepend a 0 or the resulting checksum will be incorrect. */
-         data_this_buffer--;
-         n_this_buffer++;
-         n_bytes_left++;
-         data_this_buffer[0] = 0;
-       }
-    }
-
-  sum16 = ~ip_csum_fold (sum0);
-
-  return sum16;
+    return ip_calculate_l4_checksum (vm, p0, sum0,
+                                    payload_length_host_byte_order,
+                                    (u8 *) ip0, headers_size, NULL);
+  else
+    return ip_calculate_l4_checksum (vm, 0, sum0,
+                                    payload_length_host_byte_order, NULL, 0,
+                                    data_this_buffer);
 }
 
 u32