skbedit: allow the user to specify bitmask for mark
The user may want to use only some bits of the skb mark in
his skbedit rules because the remaining part might be used by
something else.
Introduce the "mask" parameter to the skbedit actor in order
to implement such functionality.
When the mask is specified, only those bits selected by the
latter are altered really changed by the actor, while the
rest is left untouched.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tc_act/tc_skbedit.h b/include/net/tc_act/tc_skbedit.h
index 5767e9d..19cd3d3 100644
--- a/include/net/tc_act/tc_skbedit.h
+++ b/include/net/tc_act/tc_skbedit.h
@@ -27,6 +27,7 @@
u32 flags;
u32 priority;
u32 mark;
+ u32 mask;
u16 queue_mapping;
u16 ptype;
};
diff --git a/include/uapi/linux/tc_act/tc_skbedit.h b/include/uapi/linux/tc_act/tc_skbedit.h
index a4d00c6..2884425 100644
--- a/include/uapi/linux/tc_act/tc_skbedit.h
+++ b/include/uapi/linux/tc_act/tc_skbedit.h
@@ -28,6 +28,7 @@
#define SKBEDIT_F_QUEUE_MAPPING 0x2
#define SKBEDIT_F_MARK 0x4
#define SKBEDIT_F_PTYPE 0x8
+#define SKBEDIT_F_MASK 0x10
struct tc_skbedit {
tc_gen;
@@ -42,6 +43,7 @@
TCA_SKBEDIT_MARK,
TCA_SKBEDIT_PAD,
TCA_SKBEDIT_PTYPE,
+ TCA_SKBEDIT_MASK,
__TCA_SKBEDIT_MAX
};
#define TCA_SKBEDIT_MAX (__TCA_SKBEDIT_MAX - 1)
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index a133dcb..024f3a3 100644
--- a/net/sched/act_skbedit.c
+++ b/net/sched/act_skbedit.c
@@ -46,8 +46,10 @@
if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
skb->dev->real_num_tx_queues > d->queue_mapping)
skb_set_queue_mapping(skb, d->queue_mapping);
- if (d->flags & SKBEDIT_F_MARK)
- skb->mark = d->mark;
+ if (d->flags & SKBEDIT_F_MARK) {
+ skb->mark &= ~d->mask;
+ skb->mark |= d->mark & d->mask;
+ }
if (d->flags & SKBEDIT_F_PTYPE)
skb->pkt_type = d->ptype;
@@ -61,6 +63,7 @@
[TCA_SKBEDIT_QUEUE_MAPPING] = { .len = sizeof(u16) },
[TCA_SKBEDIT_MARK] = { .len = sizeof(u32) },
[TCA_SKBEDIT_PTYPE] = { .len = sizeof(u16) },
+ [TCA_SKBEDIT_MASK] = { .len = sizeof(u32) },
};
static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
@@ -71,7 +74,7 @@
struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
struct tc_skbedit *parm;
struct tcf_skbedit *d;
- u32 flags = 0, *priority = NULL, *mark = NULL;
+ u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
u16 *queue_mapping = NULL, *ptype = NULL;
bool exists = false;
int ret = 0, err;
@@ -108,6 +111,11 @@
mark = nla_data(tb[TCA_SKBEDIT_MARK]);
}
+ if (tb[TCA_SKBEDIT_MASK] != NULL) {
+ flags |= SKBEDIT_F_MASK;
+ mask = nla_data(tb[TCA_SKBEDIT_MASK]);
+ }
+
parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
exists = tcf_hash_check(tn, parm->index, a, bind);
@@ -145,6 +153,10 @@
d->mark = *mark;
if (flags & SKBEDIT_F_PTYPE)
d->ptype = *ptype;
+ /* default behaviour is to use all the bits */
+ d->mask = 0xffffffff;
+ if (flags & SKBEDIT_F_MASK)
+ d->mask = *mask;
d->tcf_action = parm->action;
@@ -182,6 +194,9 @@
if ((d->flags & SKBEDIT_F_PTYPE) &&
nla_put_u16(skb, TCA_SKBEDIT_PTYPE, d->ptype))
goto nla_put_failure;
+ if ((d->flags & SKBEDIT_F_MASK) &&
+ nla_put_u32(skb, TCA_SKBEDIT_MASK, d->mask))
+ goto nla_put_failure;
tcf_tm_dump(&t, &d->tcf_tm);
if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))