/*
* net/sched/mirred.c packet mirroring and redirect actions
*
* 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.
*
* Authors: Jamal Hadi Salim (2002-4)
*
* TODO: Add ingress support (and socket redirect support)
*
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_mirred.h>
#include <net/tc_act/tc_mirred.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
/* use generic hash table */
#define MY_TAB_SIZE 8
#define MY_TAB_MASK (MY_TAB_SIZE - 1)
static u32 idx_gen;
static struct tcf_mirred *tcf_mirred_ht[MY_TAB_SIZE];
static DEFINE_RWLOCK(mirred_lock);
/* ovewrride the defaults */
#define tcf_st tcf_mirred
#define tc_st tc_mirred
#define tcf_t_lock mirred_lock
#define tcf_ht tcf_mirred_ht
#define CONFIG_NET_ACT_INIT 1
#include <net/pkt_act.h>
static inline int
tcf_mirred_release(struct tcf_mirred *p, int bind)
{
if (p) {
if (bind)
p->bindcnt--;
p->refcnt--;
if(!p->bindcnt && p->refcnt <= 0) {
dev_put(p->dev);
tcf_hash_destroy(p);
return 1;
}
}
return 0;
}
static int
tcf_mirred_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a,
int ovr, int bind)
{
struct rtattr *tb[TCA_MIRRED_MAX];
struct tc_mirred *parm;
struct tcf_mirred *p;
struct net_device *dev = NULL;
int ret = 0;
int ok_push = 0;
if (rta == NULL || rtattr_parse_nested(tb, TCA_MIRRED_MAX, rta) < 0)
return -EINVAL;
if (tb[TCA_MIRRED_PARMS-1] == NULL ||
RTA_PAYLOAD(tb[TCA_MIRRED_PARMS-1]) < sizeof(*parm))
return -EINVAL;
parm = RTA_DATA(tb[TCA_MIRRED_PARMS-1]);
if (parm->ifindex) {
dev = __dev_get_by_index(parm->ifindex);
if (dev == NULL)
return -ENODEV;
switch (dev->type) {
case ARPHRD_TUNNEL:
case ARPHRD_TUNNEL6:
case ARPHRD_SIT:
case ARPHRD_IPGRE:
case ARPHRD_VOID:
case ARPHRD_NONE:
ok_push = 0;
break;
default:
ok_push = 1;
break;
}
}
p = tcf_hash_check(parm->index, a, ovr, bind);
if (p == NULL) {
if (!parm->ifindex)
return -EINVAL;
p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind);
if (p == NULL)
return -ENOMEM;
ret = ACT_P_CREATED;
} else {
if (!ovr) {
tcf_mirred_release(p, bind);
return -EEXIST;
}
}
spin_lock_bh(&p->lock);
p->action = parm->action;
p->eaction = parm->eaction;
if (parm->ifindex) {
p->ifindex = parm->ifindex;
if (ret != ACT_P_CREATED)
dev_put(p->dev);
p->dev = dev;
dev_hold(dev);
p->ok_push = ok_push;
}
spin_unlock_bh(&p->lock);
if (ret == ACT_P_CREATED)
tcf_hash_insert(p);
DPRINTK("tcf_mirred_init index %d action %d eaction %d device %s "
"ifindex %d\n", parm->index, parm->action, parm->eaction,
dev->name, parm->ifindex);
return ret;
}
static int
tcf_mirred_cleanup(struct tc_action *a, int bind)
{
struct tcf_mirred *p = PRIV(a, mirred);
if (p != NULL)
return tcf_mirred_release(p, bind);
return 0;
}
static int
tcf_mirred(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
{
struct tcf_mirred *p = PRIV(a, mirred);
struct net_device *dev;
struct sk_buff *skb2 = NULL;
u32 at = G_TC_AT(skb->tc_verd);
spin_lock(&p->lock);
dev = p->dev;
p->tm.lastuse = jiffies;
if (!(dev->flags&IFF_UP) ) {
if (net_ratelimit())
printk("mirred to Houston: device %s is gone!\n",
dev->name);
bad_mirred:
if (skb2 != NULL)
kfree_skb(skb2);
p->qstats.overlimits++;
p->bstats.bytes += skb->len;
p->bstats.packets++;
spin_unlock(&p->lock);
/* should we be asking for packet to be dropped?
* may make sense for redirect case only
*/
return TC_ACT_SHOT;
}
skb2 = skb_clone(skb, GFP_ATOMIC);
if (skb2 == NULL)
goto bad_mirred;
if (p->eaction != TCA_EGRESS_MIRROR && p->eaction != TCA_EGRESS_REDIR) {
if (net_ratelimit())
printk("tcf_mirred unknown action %d\n", p->eaction);
goto bad_mirred;
}
p->bstats.bytes += skb2->len;
p->bstats.packets++;
if (!(at & AT_EGRESS))
if (p->ok_push)
skb_push(skb2, skb2->dev->hard_header_len);
/* mirror is always swallowed */
if (p->eaction != TCA_EGRESS_MIRROR)
skb2->tc_verd = SET_TC_FROM(skb2->tc_verd, at);
skb2->dev = dev;
skb2->input_dev = skb->dev;
dev_queue_xmit(skb2);
spin_unlock(&p->lock);
return p->action;
}
static int
tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
unsigned char *b = skb->tail;
struct tc_mirred opt;
struct tcf_mirred *p = PRIV(a, mirred);
struct tcf_t t;
opt.index = p->index;
opt.action = p->action;
opt.refcnt = p->refcnt - ref;
opt.bindcnt = p->bindcnt - bind;
opt.eaction = p->eaction;
opt.ifindex = p->ifindex;
DPRINTK("tcf_mirred_dump index %d action %d eaction %d ifindex %d\n",
p->index, p->action, p->eaction, p->ifindex);
RTA_PUT(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt);
t.install = jiffies_to_clock_t(jiffies - p->tm.install);
t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
t.expires = jiffies_to_clock_t(p->tm.expires);
RTA_PUT(skb, TCA_MIRRED_TM, sizeof(t), &t);
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
static struct tc_action_ops act_mirred_ops = {
.kind = "mirred",
.type = TCA_ACT_MIRRED,
.capab = TCA_CAP_NONE,
.owner = THIS_MODULE,
.act = tcf_mirred,
.dump = tcf_mirred_dump,
.cleanup = tcf_mirred_cleanup,
.lookup = tcf_hash_search,
.init = tcf_mirred_init,
.walk = tcf_generic_walker
};
MODULE_AUTHOR("Jamal Hadi Salim(2002)");
MODULE_DESCRIPTION("Device Mirror/redirect actions");
MODULE_LICENSE("GPL");
static int __init
mirred_init_module(void)
{
printk("Mirror/redirect action on\n");
return tcf_register_action(&act_mirred_ops);
}
static void __exit
mirred_cleanup_module(void)
{
tcf_unregister_action(&act_mirred_ops);
}
module_init(mirred_init_module);
module_exit(mirred_cleanup_module);
