From 0ae418e6e25baadf3b75c7572d5b4fa5b749e1e3 Mon Sep 17 00:00:00 2001 From: Shannon Nelson Date: Thu, 22 Feb 2018 11:09:56 -0800 Subject: [PATCH] ixgbe: fix ipsec trailer length Fix up the Tx trailer length calculation. We can't believe the trailer len from the xstate information because it was calculated before the packet was put together and padding added. This bit of code finds the padding value in the trailer, adds it to the authentication length, and saves it so later we can put it into the Tx descriptor to tell the device where to stop the checksum calculation. Fixes: 592594704761 ("ixgbe: process the Tx ipsec offload") Signed-off-by: Shannon Nelson Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- .../net/ethernet/intel/ixgbe/ixgbe_ipsec.c | 24 ++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c index 8b7dbc8057eb..8623013e517e 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c @@ -789,11 +789,33 @@ int ixgbe_ipsec_tx(struct ixgbe_ring *tx_ring, itd->flags = 0; if (xs->id.proto == IPPROTO_ESP) { + struct sk_buff *skb = first->skb; + int ret, authlen, trailerlen; + u8 padlen; + itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_TYPE_ESP | IXGBE_ADVTXD_TUCMD_L4T_TCP; if (first->protocol == htons(ETH_P_IP)) itd->flags |= IXGBE_ADVTXD_TUCMD_IPV4; - itd->trailer_len = xs->props.trailer_len; + + /* The actual trailer length is authlen (16 bytes) plus + * 2 bytes for the proto and the padlen values, plus + * padlen bytes of padding. This ends up not the same + * as the static value found in xs->props.trailer_len (21). + * + * The "correct" way to get the auth length would be to use + * authlen = crypto_aead_authsize(xs->data); + * but since we know we only have one size to worry about + * we can let the compiler use the constant and save us a + * few CPU cycles. + */ + authlen = IXGBE_IPSEC_AUTH_BITS / 8; + + ret = skb_copy_bits(skb, skb->len - (authlen + 2), &padlen, 1); + if (unlikely(ret)) + return 0; + trailerlen = authlen + 2 + padlen; + itd->trailer_len = trailerlen; } if (tsa->encrypt) itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_ENCRYPT_EN; -- 2.30.2