sched: introduce vlan action

This tc action allows to work with vlan tagged skbs. Two supported
sub-actions are header pop and header push.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 219 insertions, 0 deletions

diff --git a/net/sched/Kconfig b/net/sched/Kconfig
index a1a8e29e5fc9..88618f8b794c 100644
--- a/net/sched/Kconfig
+++ b/net/sched/Kconfig
@@ -686,6 +686,17 @@ config NET_ACT_CSUM
           To compile this code as a module, choose M here: the
           module will be called act_csum.
 
+config NET_ACT_VLAN
+        tristate "Vlan manipulation"
+        depends on NET_CLS_ACT
+        ---help---
+          Say Y here to push or pop vlan headers.
+
+          If unsure, say N.
+
+          To compile this code as a module, choose M here: the
+          module will be called act_vlan.
+
 config NET_CLS_IND
         bool "Incoming device classification"
         depends on NET_CLS_U32 || NET_CLS_FW
diff --git a/net/sched/Makefile b/net/sched/Makefile
index 0a869a11f3e6..679f24ae7f93 100644
--- a/net/sched/Makefile
+++ b/net/sched/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_NET_ACT_PEDIT)	+= act_pedit.o
 obj-$(CONFIG_NET_ACT_SIMP)      += act_simple.o
 obj-$(CONFIG_NET_ACT_SKBEDIT)   += act_skbedit.o
 obj-$(CONFIG_NET_ACT_CSUM)      += act_csum.o
+obj-$(CONFIG_NET_ACT_VLAN)      += act_vlan.o
 obj-$(CONFIG_NET_SCH_FIFO)      += sch_fifo.o
 obj-$(CONFIG_NET_SCH_CBQ)       += sch_cbq.o
 obj-$(CONFIG_NET_SCH_HTB)       += sch_htb.o
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
new file mode 100644
index 000000000000..d735ecf0b1a7
--- /dev/null
+++ b/net/sched/act_vlan.c
@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/rtnetlink.h>
+#include <linux/if_vlan.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+
+#include <linux/tc_act/tc_vlan.h>
+#include <net/tc_act/tc_vlan.h>
+
+#define VLAN_TAB_MASK     15
+
+static int tcf_vlan(struct sk_buff *skb, const struct tc_action *a,
+                    struct tcf_result *res)
+{
+        struct tcf_vlan *v = a->priv;
+        int action;
+        int err;
+
+        spin_lock(&v->tcf_lock);
+        v->tcf_tm.lastuse = jiffies;
+        bstats_update(&v->tcf_bstats, skb);
+        action = v->tcf_action;
+
+        switch (v->tcfv_action) {
+        case TCA_VLAN_ACT_POP:
+                err = skb_vlan_pop(skb);
+                if (err)
+                        goto drop;
+                break;
+        case TCA_VLAN_ACT_PUSH:
+                err = skb_vlan_push(skb, v->tcfv_push_proto, v->tcfv_push_vid);
+                if (err)
+                        goto drop;
+                break;
+        default:
+                BUG();
+        }
+
+        goto unlock;
+
+drop:
+        action = TC_ACT_SHOT;
+        v->tcf_qstats.drops++;
+unlock:
+        spin_unlock(&v->tcf_lock);
+        return action;
+}
+
+static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
+        [TCA_VLAN_PARMS]                = { .len = sizeof(struct tc_vlan) },
+        [TCA_VLAN_PUSH_VLAN_ID]         = { .type = NLA_U16 },
+        [TCA_VLAN_PUSH_VLAN_PROTOCOL]   = { .type = NLA_U16 },
+};
+
+static int tcf_vlan_init(struct net *net, struct nlattr *nla,
+                         struct nlattr *est, struct tc_action *a,
+                         int ovr, int bind)
+{
+        struct nlattr *tb[TCA_VLAN_MAX + 1];
+        struct tc_vlan *parm;
+        struct tcf_vlan *v;
+        int action;
+        __be16 push_vid = 0;
+        __be16 push_proto = 0;
+        int ret = 0;
+        int err;
+
+        if (!nla)
+                return -EINVAL;
+
+        err = nla_parse_nested(tb, TCA_VLAN_MAX, nla, vlan_policy);
+        if (err < 0)
+                return err;
+
+        if (!tb[TCA_VLAN_PARMS])
+                return -EINVAL;
+        parm = nla_data(tb[TCA_VLAN_PARMS]);
+        switch (parm->v_action) {
+        case TCA_VLAN_ACT_POP:
+                break;
+        case TCA_VLAN_ACT_PUSH:
+                if (!tb[TCA_VLAN_PUSH_VLAN_ID])
+                        return -EINVAL;
+                push_vid = nla_get_u16(tb[TCA_VLAN_PUSH_VLAN_ID]);
+                if (push_vid >= VLAN_VID_MASK)
+                        return -ERANGE;
+
+                if (tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]) {
+                        push_proto = nla_get_be16(tb[TCA_VLAN_PUSH_VLAN_PROTOCOL]);
+                        switch (push_proto) {
+                        case htons(ETH_P_8021Q):
+                        case htons(ETH_P_8021AD):
+                                break;
+                        default:
+                                return -EPROTONOSUPPORT;
+                        }
+                } else {
+                        push_proto = htons(ETH_P_8021Q);
+                }
+                break;
+        default:
+                return -EINVAL;
+        }
+        action = parm->v_action;
+
+        if (!tcf_hash_check(parm->index, a, bind)) {
+                ret = tcf_hash_create(parm->index, est, a, sizeof(*v), bind);
+                if (ret)
+                        return ret;
+
+                ret = ACT_P_CREATED;
+        } else {
+                if (bind)
+                        return 0;
+                tcf_hash_release(a, bind);
+                if (!ovr)
+                        return -EEXIST;
+        }
+
+        v = to_vlan(a);
+
+        spin_lock_bh(&v->tcf_lock);
+
+        v->tcfv_action = action;
+        v->tcfv_push_vid = push_vid;
+        v->tcfv_push_proto = push_proto;
+
+        v->tcf_action = parm->action;
+
+        spin_unlock_bh(&v->tcf_lock);
+
+        if (ret == ACT_P_CREATED)
+                tcf_hash_insert(a);
+        return ret;
+}
+
+static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
+                         int bind, int ref)
+{
+        unsigned char *b = skb_tail_pointer(skb);
+        struct tcf_vlan *v = a->priv;
+        struct tc_vlan opt = {
+                .index    = v->tcf_index,
+                .refcnt   = v->tcf_refcnt - ref,
+                .bindcnt  = v->tcf_bindcnt - bind,
+                .action   = v->tcf_action,
+                .v_action = v->tcfv_action,
+        };
+        struct tcf_t t;
+
+        if (nla_put(skb, TCA_VLAN_PARMS, sizeof(opt), &opt))
+                goto nla_put_failure;
+
+        if (v->tcfv_action == TCA_VLAN_ACT_PUSH &&
+            (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)))
+                goto nla_put_failure;
+
+        t.install = jiffies_to_clock_t(jiffies - v->tcf_tm.install);
+        t.lastuse = jiffies_to_clock_t(jiffies - v->tcf_tm.lastuse);
+        t.expires = jiffies_to_clock_t(v->tcf_tm.expires);
+        if (nla_put(skb, TCA_VLAN_TM, sizeof(t), &t))
+                goto nla_put_failure;
+        return skb->len;
+
+nla_put_failure:
+        nlmsg_trim(skb, b);
+        return -1;
+}
+
+static struct tc_action_ops act_vlan_ops = {
+        .kind           =       "vlan",
+        .type           =       TCA_ACT_VLAN,
+        .owner          =       THIS_MODULE,
+        .act            =       tcf_vlan,
+        .dump           =       tcf_vlan_dump,
+        .init           =       tcf_vlan_init,
+};
+
+static int __init vlan_init_module(void)
+{
+        return tcf_register_action(&act_vlan_ops, VLAN_TAB_MASK);
+}
+
+static void __exit vlan_cleanup_module(void)
+{
+        tcf_unregister_action(&act_vlan_ops);
+}
+
+module_init(vlan_init_module);
+module_exit(vlan_cleanup_module);
+
+MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
+MODULE_DESCRIPTION("vlan manipulation actions");
+MODULE_LICENSE("GPL v2");