linux/net/sched/act_ipt.c

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/*
* 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 <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 09:04:11 +01:00
#include <linux/slab.h>
#include <net/netlink.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>
#define IPT_TAB_MASK 15
static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
static u32 ipt_idx_gen;
static DEFINE_RWLOCK(ipt_lock);
static struct tcf_hashinfo ipt_hash_info = {
.htab = tcf_ipt_ht,
.hmask = IPT_TAB_MASK,
.lock = &ipt_lock,
};
static int ipt_init_target(struct xt_entry_target *t, char *table, unsigned int hook)
{
struct xt_tgchk_param par;
struct xt_target *target;
int ret = 0;
target = xt_request_find_target(AF_INET, t->u.user.name,
t->u.user.revision);
if (IS_ERR(target))
return PTR_ERR(target);
t->u.kernel.target = target;
par.table = table;
par.entryinfo = NULL;
par.target = target;
par.targinfo = t->data;
par.hook_mask = hook;
par.family = NFPROTO_IPV4;
ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
if (ret < 0) {
module_put(t->u.kernel.target->me);
return ret;
}
return 0;
}
static void ipt_destroy_target(struct xt_entry_target *t)
{
struct xt_tgdtor_param par = {
.target = t->u.kernel.target,
.targinfo = t->data,
};
if (par.target->destroy != NULL)
par.target->destroy(&par);
module_put(par.target->me);
}
static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
{
int ret = 0;
if (ipt) {
if (bind)
ipt->tcf_bindcnt--;
ipt->tcf_refcnt--;
if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
ipt_destroy_target(ipt->tcfi_t);
kfree(ipt->tcfi_tname);
kfree(ipt->tcfi_t);
tcf_hash_destroy(&ipt->common, &ipt_hash_info);
ret = ACT_P_DELETED;
}
}
return ret;
}
static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
[TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
[TCA_IPT_HOOK] = { .type = NLA_U32 },
[TCA_IPT_INDEX] = { .type = NLA_U32 },
[TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) },
};
static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est,
struct tc_action *a, int ovr, int bind)
{
struct nlattr *tb[TCA_IPT_MAX + 1];
struct tcf_ipt *ipt;
struct tcf_common *pc;
struct xt_entry_target *td, *t;
char *tname;
int ret = 0, err;
u32 hook = 0;
u32 index = 0;
if (nla == NULL)
return -EINVAL;
err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
if (err < 0)
return err;
if (tb[TCA_IPT_HOOK] == NULL)
return -EINVAL;
if (tb[TCA_IPT_TARG] == NULL)
return -EINVAL;
td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
return -EINVAL;
if (tb[TCA_IPT_INDEX] != NULL)
index = nla_get_u32(tb[TCA_IPT_INDEX]);
pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
if (!pc) {
pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
&ipt_idx_gen, &ipt_hash_info);
if (IS_ERR(pc))
return PTR_ERR(pc);
ret = ACT_P_CREATED;
} else {
if (!ovr) {
tcf_ipt_release(to_ipt(pc), bind);
return -EEXIST;
}
}
ipt = to_ipt(pc);
hook = nla_get_u32(tb[TCA_IPT_HOOK]);
err = -ENOMEM;
tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
if (unlikely(!tname))
goto err1;
if (tb[TCA_IPT_TABLE] == NULL ||
nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
strcpy(tname, "mangle");
t = kmemdup(td, td->u.target_size, GFP_KERNEL);
if (unlikely(!t))
goto err2;
err = ipt_init_target(t, tname, hook);
if (err < 0)
goto err3;
spin_lock_bh(&ipt->tcf_lock);
if (ret != ACT_P_CREATED) {
ipt_destroy_target(ipt->tcfi_t);
kfree(ipt->tcfi_tname);
kfree(ipt->tcfi_t);
}
ipt->tcfi_tname = tname;
ipt->tcfi_t = t;
ipt->tcfi_hook = hook;
spin_unlock_bh(&ipt->tcf_lock);
if (ret == ACT_P_CREATED)
tcf_hash_insert(pc, &ipt_hash_info);
return ret;
err3:
kfree(t);
err2:
kfree(tname);
err1:
kfree(pc);
return err;
}
static int tcf_ipt_cleanup(struct tc_action *a, int bind)
{
struct tcf_ipt *ipt = a->priv;
return tcf_ipt_release(ipt, bind);
}
static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
int ret = 0, result = 0;
struct tcf_ipt *ipt = a->priv;
struct xt_action_param par;
if (skb_cloned(skb)) {
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return TC_ACT_UNSPEC;
}
spin_lock(&ipt->tcf_lock);
ipt->tcf_tm.lastuse = jiffies;
bstats_update(&ipt->tcf_bstats, skb);
/* yes, we have to worry about both in and out dev
* worry later - danger - this API seems to have changed
* from earlier kernels
*/
par.in = skb->dev;
par.out = NULL;
par.hooknum = ipt->tcfi_hook;
par.target = ipt->tcfi_t->u.kernel.target;
par.targinfo = ipt->tcfi_t->data;
ret = par.target->target(skb, &par);
switch (ret) {
case NF_ACCEPT:
result = TC_ACT_OK;
break;
case NF_DROP:
result = TC_ACT_SHOT;
ipt->tcf_qstats.drops++;
break;
case XT_CONTINUE:
result = TC_ACT_PIPE;
break;
default:
if (net_ratelimit())
pr_notice("tc filter: Bogus netfilter code"
" %d assume ACCEPT\n", ret);
result = TC_POLICE_OK;
break;
}
spin_unlock(&ipt->tcf_lock);
return result;
}
static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_ipt *ipt = a->priv;
struct xt_entry_target *t;
struct tcf_t tm;
struct tc_cnt c;
/* for simple targets kernel size == user size
* user name = target name
* for foolproof you need to not assume this
*/
t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
if (unlikely(!t))
goto nla_put_failure;
c.bindcnt = ipt->tcf_bindcnt - bind;
c.refcnt = ipt->tcf_refcnt - ref;
strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
NLA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
NLA_PUT_U32(skb, TCA_IPT_INDEX, ipt->tcf_index);
NLA_PUT_U32(skb, TCA_IPT_HOOK, ipt->tcfi_hook);
NLA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
NLA_PUT_STRING(skb, TCA_IPT_TABLE, ipt->tcfi_tname);
tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
NLA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
kfree(t);
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
kfree(t);
return -1;
}
static struct tc_action_ops act_ipt_ops = {
.kind = "ipt",
.hinfo = &ipt_hash_info,
.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);