[dpdk-stable] [PATCH] net: prepare the outer ipv4 hdr for checksum

[dpdk-stable] [PATCH] net: prepare the outer ipv4 hdr for checksum

[Mohsin Kazmi]

Preparation the headers for the hardware offload
misses the outer ipv4 checksum offload.
It results in bad checksum computed by hardware NIC.

This patch fixes the issue by setting the outer ipv4
checksum field to 0.

Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")
Cc: stable@dpdk.org

Signed-off-by: Mohsin Kazmi <mohsin.kazmi14@gmail.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>
---
 lib/net/rte_net.h | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/net/rte_net.h b/lib/net/rte_net.h
index 434435ffa2..e47365099e 100644
--- a/lib/net/rte_net.h
+++ b/lib/net/rte_net.h
@@ -128,8 +128,18 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf *m, uint64_t ol_flags)
 	if (!(ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK | PKT_TX_TCP_SEG)))
 		return 0;
 
-	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6))
+	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6)) {
 		inner_l3_offset += m->outer_l2_len + m->outer_l3_len;
+		/*
+		 * prepare outer ipv4 header checksum by setting it to 0,
+		 * in order to be computed by hardware NICs.
+		 */
+		if (ol_flags & PKT_TX_OUTER_IP_CKSUM) {
+			ipv4_hdr = rte_pktmbuf_mtod_offset(m,
+					struct rte_ipv4_hdr *, m->outer_l2_len);
+			ipv4_hdr->hdr_checksum = 0;
+		}
+	}
 
 	/*
 	 * Check if headers are fragmented.
-- 
2.17.1

Re: [dpdk-stable] [PATCH] net: prepare the outer ipv4 hdr for checksum

[Kinsella, Ray]

Please mark [PATCH v2], and record changes under the ---

Ray K

> -----Original Message-----
> From: Mohsin Kazmi <mohsin.kazmi14@gmail.com>
> Sent: Tuesday 29 June 2021 18:07
> To: dev@dpdk.org
> Cc: Kinsella, Ray <ray.kinsella@intel.com>; Mohsin Kazmi
> <mohsin.kazmi14@gmail.com>; stable@dpdk.org; Olivier Matz
> <olivier.matz@6wind.com>; Ananyev, Konstantin
> <konstantin.ananyev@intel.com>; Thomas Monjalon
> <thomas.monjalon@6wind.com>; Tomasz Kulasek <tomaszx.kulasek@intel.com>
> Subject: [PATCH] net: prepare the outer ipv4 hdr for checksum
> 
> Preparation the headers for the hardware offload misses the outer ipv4
> checksum offload.
> It results in bad checksum computed by hardware NIC.
> 
> This patch fixes the issue by setting the outer ipv4 checksum field to
> 0.
> 
> Fixes: 4fb7e803eb1a ("ethdev: add Tx preparation")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Mohsin Kazmi <mohsin.kazmi14@gmail.com>
> Acked-by: Qi Zhang <qi.z.zhang@intel.com>
> ---
>  lib/net/rte_net.h | 12 +++++++++++-
>  1 file changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/net/rte_net.h b/lib/net/rte_net.h index
> 434435ffa2..e47365099e 100644
> --- a/lib/net/rte_net.h
> +++ b/lib/net/rte_net.h
> @@ -128,8 +128,18 @@ rte_net_intel_cksum_flags_prepare(struct rte_mbuf
> *m, uint64_t ol_flags)
>  	if (!(ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK |
> PKT_TX_TCP_SEG)))
>  		return 0;
> 
> -	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6))
> +	if (ol_flags & (PKT_TX_OUTER_IPV4 | PKT_TX_OUTER_IPV6)) {
>  		inner_l3_offset += m->outer_l2_len + m->outer_l3_len;
> +		/*
> +		 * prepare outer ipv4 header checksum by setting it to 0,
> +		 * in order to be computed by hardware NICs.
> +		 */
> +		if (ol_flags & PKT_TX_OUTER_IP_CKSUM) {
> +			ipv4_hdr = rte_pktmbuf_mtod_offset(m,
> +					struct rte_ipv4_hdr *, m->outer_l2_len);
> +			ipv4_hdr->hdr_checksum = 0;
> +		}
> +	}
> 
>  	/*
>  	 * Check if headers are fragmented.
> --
> 2.17.1