Re: [dpdk-dev] [PATCH] app/testpmd: add parsing for multiple VLAN headers

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 4/20/2020 4:32 PM, Raslan Darawsheh wrote:
> When having multiple VLANs in the packet, parse_ethernet
> is cabable of parsing only the first vlan.
> 
> add parsing for mutliple VLAN headers in the packet.
> 
> Fixes: 51f694dd40f5 ("app/testpmd: rework checksum forward engine")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Raslan Darawsheh <rasland@mellanox.com>
> ---
>  app/test-pmd/csumonly.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/app/test-pmd/csumonly.c b/app/test-pmd/csumonly.c
> index fe19615..b0665f7 100644
> --- a/app/test-pmd/csumonly.c
> +++ b/app/test-pmd/csumonly.c
> @@ -139,22 +139,22 @@ parse_ipv6(struct rte_ipv6_hdr *ipv6_hdr, struct testpmd_offload_info *info)
>  
>  /*
>   * Parse an ethernet header to fill the ethertype, l2_len, l3_len and
> - * ipproto. This function is able to recognize IPv4/IPv6 with one optional vlan
> - * header. The l4_len argument is only set in case of TCP (useful for TSO).
> + * ipproto. This function is able to recognize IPv4/IPv6 with optional VLAN
> + * headers. The l4_len argument is only set in case of TCP (useful for TSO).
>   */
>  static void
>  parse_ethernet(struct rte_ether_hdr *eth_hdr, struct testpmd_offload_info *info)
>  {
>  	struct rte_ipv4_hdr *ipv4_hdr;
>  	struct rte_ipv6_hdr *ipv6_hdr;
> +	struct rte_vlan_hdr *vlan_hdr;
>  
>  	info->l2_len = sizeof(struct rte_ether_hdr);
>  	info->ethertype = eth_hdr->ether_type;
>  
> -	if (info->ethertype == _htons(RTE_ETHER_TYPE_VLAN)) {
> -		struct rte_vlan_hdr *vlan_hdr = (
> -			struct rte_vlan_hdr *)(eth_hdr + 1);
> -
> +	while (info->ethertype == _htons(RTE_ETHER_TYPE_VLAN)) {
> +		vlan_hdr = (struct rte_vlan_hdr *)
> +			((char *)eth_hdr + info->l2_len);
>  		info->l2_len  += sizeof(struct rte_vlan_hdr);
>  		info->ethertype = vlan_hdr->eth_proto;
>  	}
> 

Can an ethernet packet have multiple VLAN header, according IEEE 802.1Q there
can be only single VLAN header, if this is for QinQ will both TPID be same and
0x8100 (RTE_ETHER_TYPE_VLAN)?