blob: 886f46393abc46240c4ef369bee0c0f7db9e2a69 [file] [log] [blame]
/*
* net/sched/ipt.c iptables target interface
*
*TODO: Add other tables. For now we only support the ipv4 table targets
*
* 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.
*
* Copyright: Jamal Hadi Salim (2002-4)
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <linux/config.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 <linux/kmod.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_ipt.h>
#include <net/tc_act/tc_ipt.h>
#include <linux/netfilter_ipv4/ip_tables.h>
/* use generic hash table */
#define MY_TAB_SIZE 16
#define MY_TAB_MASK 15
static u32 idx_gen;
static struct tcf_ipt *tcf_ipt_ht[MY_TAB_SIZE];
/* ipt hash table lock */
static DEFINE_RWLOCK(ipt_lock);
/* ovewrride the defaults */
#define tcf_st tcf_ipt
#define tcf_t_lock ipt_lock
#define tcf_ht tcf_ipt_ht
#define CONFIG_NET_ACT_INIT
#include <net/pkt_act.h>
static int
ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
{
struct ipt_target *target;
int ret = 0;
target = ipt_find_target(t->u.user.name, t->u.user.revision);
if (!target)
return -ENOENT;
DPRINTK("ipt_init_target: found %s\n", target->name);
t->u.kernel.target = target;
if (t->u.kernel.target->checkentry
&& !t->u.kernel.target->checkentry(table, NULL, t->data,
t->u.target_size - sizeof(*t),
hook)) {
DPRINTK("ipt_init_target: check failed for `%s'.\n",
t->u.kernel.target->name);
module_put(t->u.kernel.target->me);
ret = -EINVAL;
}
return ret;
}
static void
ipt_destroy_target(struct ipt_entry_target *t)
{
if (t->u.kernel.target->destroy)
t->u.kernel.target->destroy(t->data,
t->u.target_size - sizeof(*t));
module_put(t->u.kernel.target->me);
}
static int
tcf_ipt_release(struct tcf_ipt *p, int bind)
{
int ret = 0;
if (p) {
if (bind)
p->bindcnt--;
p->refcnt--;
if (p->bindcnt <= 0 && p->refcnt <= 0) {
ipt_destroy_target(p->t);
kfree(p->tname);
kfree(p->t);
tcf_hash_destroy(p);
ret = ACT_P_DELETED;
}
}
return ret;
}
static int
tcf_ipt_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a,
int ovr, int bind)
{
struct rtattr *tb[TCA_IPT_MAX];
struct tcf_ipt *p;
struct ipt_entry_target *td, *t;
char *tname;
int ret = 0, err;
u32 hook = 0;
u32 index = 0;
if (rta == NULL || rtattr_parse_nested(tb, TCA_IPT_MAX, rta) < 0)
return -EINVAL;
if (tb[TCA_IPT_HOOK-1] == NULL ||
RTA_PAYLOAD(tb[TCA_IPT_HOOK-1]) < sizeof(u32))
return -EINVAL;
if (tb[TCA_IPT_TARG-1] == NULL ||
RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < sizeof(*t))
return -EINVAL;
td = (struct ipt_entry_target *)RTA_DATA(tb[TCA_IPT_TARG-1]);
if (RTA_PAYLOAD(tb[TCA_IPT_TARG-1]) < td->u.target_size)
return -EINVAL;
if (tb[TCA_IPT_INDEX-1] != NULL &&
RTA_PAYLOAD(tb[TCA_IPT_INDEX-1]) >= sizeof(u32))
index = *(u32 *)RTA_DATA(tb[TCA_IPT_INDEX-1]);
p = tcf_hash_check(index, a, ovr, bind);
if (p == NULL) {
p = tcf_hash_create(index, est, a, sizeof(*p), ovr, bind);
if (p == NULL)
return -ENOMEM;
ret = ACT_P_CREATED;
} else {
if (!ovr) {
tcf_ipt_release(p, bind);
return -EEXIST;
}
}
hook = *(u32 *)RTA_DATA(tb[TCA_IPT_HOOK-1]);
err = -ENOMEM;
tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
if (tname == NULL)
goto err1;
if (tb[TCA_IPT_TABLE - 1] == NULL ||
rtattr_strlcpy(tname, tb[TCA_IPT_TABLE-1], IFNAMSIZ) >= IFNAMSIZ)
strcpy(tname, "mangle");
t = kmalloc(td->u.target_size, GFP_KERNEL);
if (t == NULL)
goto err2;
memcpy(t, td, td->u.target_size);
if ((err = ipt_init_target(t, tname, hook)) < 0)
goto err3;
spin_lock_bh(&p->lock);
if (ret != ACT_P_CREATED) {
ipt_destroy_target(p->t);
kfree(p->tname);
kfree(p->t);
}
p->tname = tname;
p->t = t;
p->hook = hook;
spin_unlock_bh(&p->lock);
if (ret == ACT_P_CREATED)
tcf_hash_insert(p);
return ret;
err3:
kfree(t);
err2:
kfree(tname);
err1:
kfree(p);
return err;
}
static int
tcf_ipt_cleanup(struct tc_action *a, int bind)
{
struct tcf_ipt *p = PRIV(a, ipt);
return tcf_ipt_release(p, bind);
}
static int
tcf_ipt(struct sk_buff **pskb, struct tc_action *a)
{
int ret = 0, result = 0;
struct tcf_ipt *p = PRIV(a, ipt);
struct sk_buff *skb = *pskb;
if (skb_cloned(skb)) {
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return TC_ACT_UNSPEC;
}
spin_lock(&p->lock);
p->tm.lastuse = jiffies;
p->bstats.bytes += skb->len;
p->bstats.packets++;
/* yes, we have to worry about both in and out dev
worry later - danger - this API seems to have changed
from earlier kernels */
ret = p->t->u.kernel.target->target(&skb, skb->dev, NULL,
p->hook, p->t->data, NULL);
switch (ret) {
case NF_ACCEPT:
result = TC_ACT_OK;
break;
case NF_DROP:
result = TC_ACT_SHOT;
p->qstats.drops++;
break;
case IPT_CONTINUE:
result = TC_ACT_PIPE;
break;
default:
if (net_ratelimit())
printk("Bogus netfilter code %d assume ACCEPT\n", ret);
result = TC_POLICE_OK;
break;
}
spin_unlock(&p->lock);
return result;
}
static int
tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
struct ipt_entry_target *t;
struct tcf_t tm;
struct tc_cnt c;
unsigned char *b = skb->tail;
struct tcf_ipt *p = PRIV(a, ipt);
/* for simple targets kernel size == user size
** user name = target name
** for foolproof you need to not assume this
*/
t = kmalloc(p->t->u.user.target_size, GFP_ATOMIC);
if (t == NULL)
goto rtattr_failure;
c.bindcnt = p->bindcnt - bind;
c.refcnt = p->refcnt - ref;
memcpy(t, p->t, p->t->u.user.target_size);
strcpy(t->u.user.name, p->t->u.kernel.target->name);
DPRINTK("\ttcf_ipt_dump tablename %s length %d\n", p->tname,
strlen(p->tname));
DPRINTK("\tdump target name %s size %d size user %d "
"data[0] %x data[1] %x\n", p->t->u.kernel.target->name,
p->t->u.target_size, p->t->u.user.target_size,
p->t->data[0], p->t->data[1]);
RTA_PUT(skb, TCA_IPT_TARG, p->t->u.user.target_size, t);
RTA_PUT(skb, TCA_IPT_INDEX, 4, &p->index);
RTA_PUT(skb, TCA_IPT_HOOK, 4, &p->hook);
RTA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
RTA_PUT(skb, TCA_IPT_TABLE, IFNAMSIZ, p->tname);
tm.install = jiffies_to_clock_t(jiffies - p->tm.install);
tm.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
tm.expires = jiffies_to_clock_t(p->tm.expires);
RTA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
static struct tc_action_ops act_ipt_ops = {
.kind = "ipt",
.type = TCA_ACT_IPT,
.capab = TCA_CAP_NONE,
.owner = THIS_MODULE,
.act = tcf_ipt,
.dump = tcf_ipt_dump,
.cleanup = tcf_ipt_cleanup,
.lookup = tcf_hash_search,
.init = tcf_ipt_init,
.walk = tcf_generic_walker
};
MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Iptables target actions");
MODULE_LICENSE("GPL");
static int __init
ipt_init_module(void)
{
return tcf_register_action(&act_ipt_ops);
}
static void __exit
ipt_cleanup_module(void)
{
tcf_unregister_action(&act_ipt_ops);
}
module_init(ipt_init_module);
module_exit(ipt_cleanup_module);