ip: add support for buffer offload metadata in ip midchain

The offload should be handled by gso node or by the NIC
if the latter has the relevant capabilities. But ip midchain
is missing the support for buffer offload metadata in case
of GSO packet.

This patch adds the relevant support to add the buffer metadata
if the packet is GSO/IPIP to be handled accordingly.

Type: improvement

Change-Id: I17f5d71bf4c5f43a85ca3f2fbebfa1426b42ef69
Signed-off-by: Arthur de Kerhor <arthurdekerhor@gmail.com>
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

5 files changed, 78 insertions, 44 deletions

diff --git a/src/vnet/adj/adj_dp.h b/src/vnet/adj/adj_dp.h
index aff1a2b1f43..186044b90ad 100644
--- a/src/vnet/adj/adj_dp.h
+++ b/src/vnet/adj/adj_dp.h
@@ -36,22 +36,36 @@ adj_midchain_ipip44_fixup (vlib_main_t * vm,
   ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
 
   if (PREDICT_TRUE(TUNNEL_ENCAP_DECAP_FLAG_NONE == flags))
-  {
-      ip_csum_t sum;
-      u16 old,new;
-
-      old = 0;
-      new = ip4->length;
-
-      sum = ip4->checksum;
-      sum = ip_csum_update (sum, old, new, ip4_header_t, length);
-      ip4->checksum = ip_csum_fold (sum);
-  }
+    {
+      if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+       {
+         vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip4 - b->data;
+         vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TNL_IPIP |
+                                     VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM);
+       }
+      else
+       {
+         ip_csum_t sum;
+         u16 old,new;
+         old = 0;
+         new = ip4->length;
+         sum = ip4->checksum;
+         sum = ip_csum_update (sum, old, new, ip4_header_t, length);
+         ip4->checksum = ip_csum_fold (sum);
+       }
+    }
   else
-  {
+    {
       tunnel_encap_fixup_4o4 (flags, ip4 + 1, ip4);
-      ip4->checksum = ip4_header_checksum (ip4);
-  }
+      if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+       {
+         vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip4 - b->data;
+         vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TNL_IPIP |
+                                     VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM);
+       }
+      else
+        ip4->checksum = ip4_header_checksum (ip4);
+    }
 }
 
 static_always_inline void
diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index eb2b7ee04bc..e85c888f669 100644
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -2223,9 +2223,6 @@ ip4_rewrite_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 						adj0->ia_cfg_index);
 
 	  next[0] = next_index;
-	  if (is_midchain)
-	    vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
-					0 /* is_ip6 */ );
 	}
       else
 	{
@@ -2248,9 +2245,6 @@ ip4_rewrite_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 						&next_index, b[1],
 						adj1->ia_cfg_index);
 	  next[1] = next_index;
-	  if (is_midchain)
-	    vnet_calc_checksums_inline (vm, b[1], 1 /* is_ip4 */ ,
-					0 /* is_ip6 */ );
 	}
       else
 	{
@@ -2400,9 +2394,6 @@ ip4_rewrite_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 
 	  if (is_midchain)
 	    {
-	      vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
-					  0 /* is_ip6 */ );
-
 	      /* Guess we are only writing on ipv4 header. */
 	      vnet_rewrite_one_header (adj0[0], ip0, sizeof (ip4_header_t));
 	    }
@@ -2506,10 +2497,6 @@ ip4_rewrite_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 
 	  if (is_midchain)
 	    {
-	      /* this acts on the packet that is about to be encapped */
-	      vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
-					  0 /* is_ip6 */ );
-
 	      /* Guess we are only writing on ipv4 header. */
 	      vnet_rewrite_one_header (adj0[0], ip0, sizeof (ip4_header_t));
 	    }
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index 1f7fc3f66fa..06c473b1495 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -1971,13 +1971,6 @@ ip6_rewrite_inline_with_gso (vlib_main_t * vm,
 
 	  if (is_midchain)
 	    {
-	      /* before we paint on the next header, update the L4
-	       * checksums if required, since there's no offload on a tunnel */
-	      vnet_calc_checksums_inline (vm, p0, 0 /* is_ip4 */ ,
-					  1 /* is_ip6 */ );
-	      vnet_calc_checksums_inline (vm, p1, 0 /* is_ip4 */ ,
-					  1 /* is_ip6 */ );
-
 	      /* Guess we are only writing on ipv6 header. */
 	      vnet_rewrite_two_headers (adj0[0], adj1[0],
 					ip0, ip1, sizeof (ip6_header_t));
@@ -2071,9 +2064,6 @@ ip6_rewrite_inline_with_gso (vlib_main_t * vm,
 
 	  if (is_midchain)
 	    {
-	      vnet_calc_checksums_inline (vm, p0, 0 /* is_ip4 */ ,
-					  1 /* is_ip6 */ );
-
 	      /* Guess we are only writing on ip6 header. */
 	      vnet_rewrite_one_header (adj0[0], ip0, sizeof (ip6_header_t));
 	    }
diff --git a/src/vnet/ipip/ipip.c b/src/vnet/ipip/ipip.c
index ec329e21eea..aaf21468d1e 100644
--- a/src/vnet/ipip/ipip.c
+++ b/src/vnet/ipip/ipip.c
@@ -148,7 +148,14 @@ ipip64_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
   ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
   tunnel_encap_fixup_6o4 (flags, ((ip6_header_t *) (ip4 + 1)), ip4);
 
-  ip4->checksum = ip4_header_checksum (ip4);
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip4 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM |
+					  VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
+  else
+    ip4->checksum = ip4_header_checksum (ip4);
 }
 
 static void
@@ -164,7 +171,14 @@ ipip44_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
   ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
   tunnel_encap_fixup_4o4 (flags, ip4 + 1, ip4);
 
-  ip4->checksum = ip4_header_checksum (ip4);
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip4 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM |
+					  VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
+  else
+    ip4->checksum = ip4_header_checksum (ip4);
 }
 
 static void
@@ -185,6 +199,12 @@ ipip46_fixup (vlib_main_t * vm, const ip_adjacency_t * adj, vlib_buffer_t * b,
     clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) -
 			  sizeof (*ip6));
   tunnel_encap_fixup_4o6 (flags, b, ((ip4_header_t *) (ip6 + 1)), ip6);
+
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip6 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
 }
 
 static void
@@ -205,6 +225,12 @@ ipip66_fixup (vlib_main_t * vm,
     clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) -
 			  sizeof (*ip6));
   tunnel_encap_fixup_6o6 (flags, ip6 + 1, ip6);
+
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip6 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
 }
 
 static void
@@ -226,6 +252,12 @@ ipipm6_fixup (vlib_main_t *vm, const ip_adjacency_t *adj, vlib_buffer_t *b,
     clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) - sizeof (*ip6));
   tunnel_encap_fixup_mplso6 (flags, b, (mpls_unicast_header_t *) (ip6 + 1),
 			     ip6);
+
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip6 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
 }
 
 static void
@@ -245,7 +277,15 @@ ipipm4_fixup (vlib_main_t *vm, const ip_adjacency_t *adj, vlib_buffer_t *b,
   ip4->length =
     clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b) - sizeof (*ip4));
   tunnel_encap_fixup_mplso4 (flags, (mpls_unicast_header_t *) (ip4 + 1), ip4);
-  ip4->checksum = ip4_header_checksum (ip4);
+
+  if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_GSO))
+    {
+      vnet_buffer2 (b)->outer_l3_hdr_offset = (u8 *) ip4 - b->data;
+      vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM |
+					  VNET_BUFFER_OFFLOAD_F_TNL_IPIP);
+    }
+  else
+    ip4->checksum = ip4_header_checksum (ip4);
 }
 
 static void
diff --git a/src/vnet/ipsec/esp_encrypt.c b/src/vnet/ipsec/esp_encrypt.c
index d3a06dc8786..dd47053874c 100644
--- a/src/vnet/ipsec/esp_encrypt.c
+++ b/src/vnet/ipsec/esp_encrypt.c
@@ -18,6 +18,7 @@
 #include <vnet/vnet.h>
 #include <vnet/api_errno.h>
 #include <vnet/ip/ip.h>
+#include <vnet/interface_output.h>
 
 #include <vnet/crypto/crypto.h>
 
@@ -148,11 +149,9 @@ esp_update_ip4_hdr (ip4_header_t * ip4, u16 len, int is_transport, int is_udp)
   if (is_transport)
     {
       u8 prot = is_udp ? IP_PROTOCOL_UDP : IP_PROTOCOL_IPSEC_ESP;
-
-      sum = ip_csum_update (ip4->checksum, ip4->protocol,
-			    prot, ip4_header_t, protocol);
+      sum = ip_csum_update (ip4->checksum, ip4->protocol, prot, ip4_header_t,
+			    protocol);
       ip4->protocol = prot;
-
       sum = ip_csum_update (sum, old_len, len, ip4_header_t, length);
     }
   else
@@ -663,6 +662,10 @@ esp_encrypt_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
 			 CLIB_CACHE_LINE_BYTES, LOAD);
 	}
 
+      vnet_calc_checksums_inline (vm, b[0], b[0]->flags & VNET_BUFFER_F_IS_IP4,
+				  b[0]->flags & VNET_BUFFER_F_IS_IP6);
+      vnet_calc_outer_checksums_inline (vm, b[0]);
+
       if (is_tun)
 	{
 	  /* we are on a ipsec tunnel's feature arc */