From f5462369f3ad22c9d19f54832faa2b6e61449f66 Mon Sep 17 00:00:00 2001
From: Mohsin Kazmi <sykazmi@cisco.com>
Date: Tue, 23 Feb 2021 15:55:04 +0100
Subject: devices: add support for pseudo header checksum

Type: improvement

Linux uses pseudo header checksum when checksum of l4 is offloaded.
This patch adds similar support in virtual interfaces.

Change-Id: I6a94d1104e59356f95057e7c122e3be9cd8659a3
Signed-off-by: Aloys Augustin <aloaugus@cisco.com>
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>
---
 src/vnet/devices/virtio/vhost_user_output.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

(limited to 'src/vnet/devices/virtio/vhost_user_output.c')

diff --git a/src/vnet/devices/virtio/vhost_user_output.c b/src/vnet/devices/virtio/vhost_user_output.c
index 4efafa85333..15e39a11692 100644
--- a/src/vnet/devices/virtio/vhost_user_output.c
+++ b/src/vnet/devices/virtio/vhost_user_output.c
@@ -37,6 +37,7 @@
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/devices/devices.h>
 #include <vnet/feature/feature.h>
+#include <vnet/ip/ip_psh_cksum.h>
 
 #include <vnet/devices/virtio/vhost_user.h>
 #include <vnet/devices/virtio/vhost_user_inline.h>
@@ -208,27 +209,40 @@ vhost_user_handle_tx_offload (vhost_user_intf_t * vui, vlib_buffer_t * b,
   int is_ip4 = b->flags & VNET_BUFFER_F_IS_IP4;
   int is_ip6 = b->flags & VNET_BUFFER_F_IS_IP6;
   vnet_buffer_oflags_t oflags = vnet_buffer (b)->oflags;
+  u16 psh_cksum = 0;
+  ip4_header_t *ip4 = 0;
+  ip6_header_t *ip6 = 0;
 
   ASSERT (!(is_ip4 && is_ip6));
   vnet_generic_header_offset_parser (b, &gho, 1 /* l2 */ , is_ip4, is_ip6);
   if (oflags & VNET_BUFFER_OFFLOAD_F_IP_CKSUM)
     {
-      ip4_header_t *ip4;
-
       ip4 =
 	(ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
       ip4->checksum = ip4_header_checksum (ip4);
+      psh_cksum = ip4_pseudo_header_cksum (ip4);
+    }
+  else
+    {
+      ip6 = (ip6_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
+      psh_cksum = ip6_pseudo_header_cksum (ip6);
     }
 
   /* checksum offload */
   if (oflags & VNET_BUFFER_OFFLOAD_F_UDP_CKSUM)
     {
+      udp_header_t *udp =
+	(udp_header_t *) (vlib_buffer_get_current (b) + gho.l4_hdr_offset);
+      udp->checksum = psh_cksum;
       hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
       hdr->csum_start = gho.l4_hdr_offset;
       hdr->csum_offset = offsetof (udp_header_t, checksum);
     }
   else if (oflags & VNET_BUFFER_OFFLOAD_F_TCP_CKSUM)
     {
+      tcp_header_t *tcp =
+	(tcp_header_t *) (vlib_buffer_get_current (b) + gho.l4_hdr_offset);
+      tcp->checksum = psh_cksum;
       hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
       hdr->csum_start = gho.l4_hdr_offset;
       hdr->csum_offset = offsetof (tcp_header_t, checksum);
-- 
cgit 1.2.3-korg