Commit d692a637 authored Aug 09, 2021 by Muhammad Falak R Wani Committed by Daniel Borkmann Aug 10, 2021

samples, bpf: Add an explict comment to handle nested vlan tagging.

A codeblock for handling nested vlan trips newbies into thinking it as
duplicate code. Explicitly add a comment to clarify.

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210809070046.32142-1-falakreyaz@gmail.com

parent 6aab1c81

samples/bpf/xdp1_kern.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -57,6 +57,7 @@ int xdp_prog1(struct xdp_md *ctx)

	h_proto = eth->h_proto;		h_proto = eth->h_proto;

			/* Handle VLAN tagged packet */
	if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {		if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {
	struct vlan_hdr *vhdr;		struct vlan_hdr *vhdr;

	@@ -66,6 +67,7 @@ int xdp_prog1(struct xdp_md *ctx)
	return rc;		return rc;
	h_proto = vhdr->h_vlan_encapsulated_proto;		h_proto = vhdr->h_vlan_encapsulated_proto;
	}		}
			/* Handle double VLAN tagged packet */
	if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {		if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {
	struct vlan_hdr *vhdr;		struct vlan_hdr *vhdr;

samples/bpf/xdp2_kern.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -73,6 +73,7 @@ int xdp_prog1(struct xdp_md *ctx)

	h_proto = eth->h_proto;		h_proto = eth->h_proto;

			/* Handle VLAN tagged packet */
	if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {		if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {
	struct vlan_hdr *vhdr;		struct vlan_hdr *vhdr;

	@@ -82,6 +83,7 @@ int xdp_prog1(struct xdp_md *ctx)
	return rc;		return rc;
	h_proto = vhdr->h_vlan_encapsulated_proto;		h_proto = vhdr->h_vlan_encapsulated_proto;
	}		}
			/* Handle double VLAN tagged packet */
	if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {		if (h_proto == htons(ETH_P_8021Q) \|\| h_proto == htons(ETH_P_8021AD)) {
	struct vlan_hdr *vhdr;		struct vlan_hdr *vhdr;