esp4: Support RX checksum with crypto offload
Keep the device's reported ip_summed indication in case crypto
was offloaded by the device. Subtract the csum values of the
stripped parts (esp header+iv, esp trailer+auth_data) to keep
value correct.
Note: CHECKSUM_COMPLETE should be indicated only if skb->csum
has the post-decryption offload csum value.
Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 0cbee0a..741acd7 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -510,7 +510,8 @@ int esp_input_done2(struct sk_buff *skb, int err)
int elen = skb->len - hlen;
int ihl;
u8 nexthdr[2];
- int padlen;
+ int padlen, trimlen;
+ __wsum csumdiff;
if (!xo || (xo && !(xo->flags & CRYPTO_DONE)))
kfree(ESP_SKB_CB(skb)->tmp);
@@ -568,8 +569,15 @@ int esp_input_done2(struct sk_buff *skb, int err)
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
- pskb_trim(skb, skb->len - alen - padlen - 2);
- __skb_pull(skb, hlen);
+ trimlen = alen + padlen + 2;
+ if (skb->ip_summed == CHECKSUM_COMPLETE) {
+ csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0);
+ skb->csum = csum_block_sub(skb->csum, csumdiff,
+ skb->len - trimlen);
+ }
+ pskb_trim(skb, skb->len - trimlen);
+
+ skb_pull_rcsum(skb, hlen);
if (x->props.mode == XFRM_MODE_TUNNEL)
skb_reset_transport_header(skb);
else