net/sched: act_vlan: Introduce TCA_VLAN_ACT_MODIFY vlan action

TCA_VLAN_ACT_MODIFY allows one to change an existing tag.

It accepts same attributes as TCA_VLAN_ACT_PUSH (protocol, id,
priority).
If packet is vlan tagged, then the tag gets overwritten according to
user specified attributes.

For example, this allows user to replace a tag's vid while preserving
its priority bits (as opposed to "action vlan pop pipe action vlan push").

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Shmulik Ladkani 2016-09-19 19:11:10 +03:00 committed by David S. Miller
parent bfca4c520f
commit 45a497f2d1
2 changed files with 29 additions and 1 deletions

View File

@ -16,6 +16,7 @@
#define TCA_VLAN_ACT_POP 1
#define TCA_VLAN_ACT_PUSH 2
#define TCA_VLAN_ACT_MODIFY 3
struct tc_vlan {
tc_gen;

View File

@ -30,6 +30,7 @@ static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
struct tcf_vlan *v = to_vlan(a);
int action;
int err;
u16 tci;
spin_lock(&v->tcf_lock);
tcf_lastuse_update(&v->tcf_tm);
@ -48,6 +49,30 @@ static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
if (err)
goto drop;
break;
case TCA_VLAN_ACT_MODIFY:
/* No-op if no vlan tag (either hw-accel or in-payload) */
if (!skb_vlan_tagged(skb))
goto unlock;
/* extract existing tag (and guarantee no hw-accel tag) */
if (skb_vlan_tag_present(skb)) {
tci = skb_vlan_tag_get(skb);
skb->vlan_tci = 0;
} else {
/* in-payload vlan tag, pop it */
err = __skb_vlan_pop(skb, &tci);
if (err)
goto drop;
}
/* replace the vid */
tci = (tci & ~VLAN_VID_MASK) | v->tcfv_push_vid;
/* replace prio bits, if tcfv_push_prio specified */
if (v->tcfv_push_prio) {
tci &= ~VLAN_PRIO_MASK;
tci |= v->tcfv_push_prio << VLAN_PRIO_SHIFT;
}
/* put updated tci as hwaccel tag */
__vlan_hwaccel_put_tag(skb, v->tcfv_push_proto, tci);
break;
default:
BUG();
}
@ -102,6 +127,7 @@ static int tcf_vlan_init(struct net *net, struct nlattr *nla,
case TCA_VLAN_ACT_POP:
break;
case TCA_VLAN_ACT_PUSH:
case TCA_VLAN_ACT_MODIFY:
if (!tb[TCA_VLAN_PUSH_VLAN_ID]) {
if (exists)
tcf_hash_release(*a, bind);
@ -185,7 +211,8 @@ static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
if (v->tcfv_action == TCA_VLAN_ACT_PUSH &&
if ((v->tcfv_action == TCA_VLAN_ACT_PUSH ||
v->tcfv_action == TCA_VLAN_ACT_MODIFY) &&
(nla_put_u16(skb, TCA_VLAN_PUSH_VLAN_ID, v->tcfv_push_vid) ||
nla_put_be16(skb, TCA_VLAN_PUSH_VLAN_PROTOCOL,
v->tcfv_push_proto) ||