app/testpmd: fix Tx checksum calculation for tunnel

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: 6b520d54ebfe ("app/testpmd: use Tx preparation in checksum engine")
Cc: stable@dpdk.org
Signed-off-by: Gregory Etelson <getelson@nvidia.com>
Acked-by: Ori Kam <orika@nvidia.com>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Acked-by: Xiaoyun Li <xiaoyun.li@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

diff --git a/app/test-pmd/csumonly.c b/app/test-pmd/csumonly.c
index 0161f72..bd5ad64 100644 (file)
--- a/app/test-pmd/csumonly.c
+++ b/app/test-pmd/csumonly.c
@@ -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 */
                }