[v3] app/testpmd: fix TX checksum calculation for tunnel
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Commit Message
csumonly engine calculates TX checksum of a tunnelled packet for outer
headers only or separately for outer and inner headers. The
calculation method is determined by checksum configuration options.
If TX checksum calculation is separated, the inner headers are
processed before outer headers.
Inner headers processing sets checksum values to 0 unconditionally.
If TX configuration offloads inner checksums only, outer checksum
calculation in software will read 0 instead of real values and
produce wrong result.
The patch zeroes inner checksums only before software calculation.
Fixes: 51f694dd40f5 ("app/testpmd: rework checksum forward engine")
Cc: stable@dpdk.org
Signed-off-by: Gregory Etelson <getelson@nvidia.com>
---
v2:
remove blank line between Fixes and Cc
explicitly compare with 0 value in `if ()`
v3:
update the patch comment
---
app/test-pmd/csumonly.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
Comments
On Thu, Jul 29, 2021 at 12:39:48PM +0300, Gregory Etelson wrote:
> csumonly engine calculates TX checksum of a tunnelled packet for outer
> headers only or separately for outer and inner headers. The
> calculation method is determined by checksum configuration options.
> If TX checksum calculation is separated, the inner headers are
> processed before outer headers.
>
> Inner headers processing sets checksum values to 0 unconditionally.
> If TX configuration offloads inner checksums only, outer checksum
> calculation in software will read 0 instead of real values and
> produce wrong result.
>
> The patch zeroes inner checksums only before software calculation.
>
> Fixes: 51f694dd40f5 ("app/testpmd: rework checksum forward engine")
> Cc: stable@dpdk.org
As said previously, I think the correct Fixes line is:
Fixes: 6b520d54ebfe ("app/testpmd: use Tx preparation in checksum engine")
Acked-by: Olivier Matz <olivier.matz@6wind.com>
Thanks
Hello Olivier,
> >
> > Fixes: 51f694dd40f5 ("app/testpmd: rework checksum forward engine")
> > Cc: stable@dpdk.org
>
> As said previously, I think the correct Fixes line is:
> Fixes: 6b520d54ebfe ("app/testpmd: use Tx preparation in checksum engine")
>
I updated the Fixes hash in v4.
> Acked-by: Olivier Matz <olivier.matz@6wind.com>
>
> Thanks
@@ -480,17 +480,18 @@ process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
if (info->ethertype == _htons(RTE_ETHER_TYPE_IPV4)) {
ipv4_hdr = l3_hdr;
- ipv4_hdr->hdr_checksum = 0;
ol_flags |= PKT_TX_IPV4;
if (info->l4_proto == IPPROTO_TCP && tso_segsz) {
ol_flags |= PKT_TX_IP_CKSUM;
} else {
- if (tx_offloads & DEV_TX_OFFLOAD_IPV4_CKSUM)
+ if (tx_offloads & DEV_TX_OFFLOAD_IPV4_CKSUM) {
ol_flags |= PKT_TX_IP_CKSUM;
- else
+ } else if (ipv4_hdr->hdr_checksum != 0) {
+ ipv4_hdr->hdr_checksum = 0;
ipv4_hdr->hdr_checksum =
rte_ipv4_cksum(ipv4_hdr);
+ }
}
} else if (info->ethertype == _htons(RTE_ETHER_TYPE_IPV6))
ol_flags |= PKT_TX_IPV6;
@@ -501,10 +502,10 @@ process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
udp_hdr = (struct rte_udp_hdr *)((char *)l3_hdr + info->l3_len);
/* do not recalculate udp cksum if it was 0 */
if (udp_hdr->dgram_cksum != 0) {
- udp_hdr->dgram_cksum = 0;
- if (tx_offloads & DEV_TX_OFFLOAD_UDP_CKSUM)
+ if (tx_offloads & DEV_TX_OFFLOAD_UDP_CKSUM) {
ol_flags |= PKT_TX_UDP_CKSUM;
- else {
+ } else {
+ udp_hdr->dgram_cksum = 0;
udp_hdr->dgram_cksum =
get_udptcp_checksum(l3_hdr, udp_hdr,
info->ethertype);
@@ -514,12 +515,12 @@ process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
ol_flags |= PKT_TX_UDP_SEG;
} else if (info->l4_proto == IPPROTO_TCP) {
tcp_hdr = (struct rte_tcp_hdr *)((char *)l3_hdr + info->l3_len);
- tcp_hdr->cksum = 0;
if (tso_segsz)
ol_flags |= PKT_TX_TCP_SEG;
- else if (tx_offloads & DEV_TX_OFFLOAD_TCP_CKSUM)
+ else if (tx_offloads & DEV_TX_OFFLOAD_TCP_CKSUM) {
ol_flags |= PKT_TX_TCP_CKSUM;
- else {
+ } else if (tcp_hdr->cksum != 0) {
+ tcp_hdr->cksum = 0;
tcp_hdr->cksum =
get_udptcp_checksum(l3_hdr, tcp_hdr,
info->ethertype);
@@ -529,13 +530,13 @@ process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
} else if (info->l4_proto == IPPROTO_SCTP) {
sctp_hdr = (struct rte_sctp_hdr *)
((char *)l3_hdr + info->l3_len);
- sctp_hdr->cksum = 0;
/* sctp payload must be a multiple of 4 to be
* offloaded */
if ((tx_offloads & DEV_TX_OFFLOAD_SCTP_CKSUM) &&
((ipv4_hdr->total_length & 0x3) == 0)) {
ol_flags |= PKT_TX_SCTP_CKSUM;
- } else {
+ } else if (sctp_hdr->cksum != 0) {
+ sctp_hdr->cksum = 0;
/* XXX implement CRC32c, example available in
* RFC3309 */
}