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netfilter: xt_recent: IPv6 support

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This updates xt_recent to support the IPv6 address family.
The new /proc/net/xt_recent directory must be used for this.
The old proc interface can also be configured out.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Jan Engelhardt 2008-10-08 11:35:00 +02:00 committed by Patrick McHardy
parent e948b20a71
commit 079aa88fe7
3 changed files with 256 additions and 54 deletions
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3
Documentation/feature-removal-schedule.txt
View File

@ -250,6 +250,9 @@ What (Why):
- xt_mark match revision 0
(superseded by xt_mark match revision 1)
- xt_recent: the old ipt_recent proc dir
(superseded by /proc/net/xt_recent)
When: January 2009 or Linux 2.7.0, whichever comes first
Why: Superseded by newer revisions or modules
Who: Jan Engelhardt <jengelh@computergmbh.de>

7
net/netfilter/Kconfig
View File

@ -743,6 +743,13 @@ config NETFILTER_XT_MATCH_RECENT
Short options are available by using 'iptables -m recent -h'
Official Website: <http://snowman.net/projects/ipt_recent/>
config NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
bool 'Enable obsolete /proc/net/ipt_recent'
depends on NETFILTER_XT_MATCH_RECENT && PROC_FS
---help---
This option enables the old /proc/net/ipt_recent interface,
which has been obsoleted by /proc/net/xt_recent.
config NETFILTER_XT_MATCH_SCTP
tristate '"sctp" protocol match support (EXPERIMENTAL)'
depends on NETFILTER_XTABLES && EXPERIMENTAL

300
net/netfilter/xt_recent.c
View File

@ -1,5 +1,6 @@
/*
* Copyright (c) 2006 Patrick McHardy <kaber@trash.net>
* Copyright © CC Computer Consultants GmbH, 2007 - 2008
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@ -13,6 +14,8 @@
*/
#include <linux/init.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
@ -30,9 +33,11 @@
#include <linux/netfilter/xt_recent.h>
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>");
MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching for IPv4");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_recent");
MODULE_ALIAS("ip6t_recent");
static unsigned int ip_list_tot = 100;
static unsigned int ip_pkt_list_tot = 20;
@ -49,14 +54,15 @@ module_param(ip_list_gid, uint, 0400);
MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list");
MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP to remember (max. 255)");
MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs");
MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/ipt_recent/* files");
MODULE_PARM_DESC(ip_list_uid,"owner of /proc/net/ipt_recent/* files");
MODULE_PARM_DESC(ip_list_gid,"owning group of /proc/net/ipt_recent/* files");
MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/xt_recent/* files");
MODULE_PARM_DESC(ip_list_uid,"owner of /proc/net/xt_recent/* files");
MODULE_PARM_DESC(ip_list_gid,"owning group of /proc/net/xt_recent/* files");
struct recent_entry {
struct list_head list;
struct list_head lru_list;
__be32 addr;
union nf_inet_addr addr;
u_int16_t family;
u_int8_t ttl;
u_int8_t index;
u_int16_t nstamps;
@ -67,7 +73,7 @@ struct recent_table {
struct list_head list;
char name[XT_RECENT_NAME_LEN];
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *proc;
struct proc_dir_entry *proc_old, *proc;
#endif
unsigned int refcnt;
unsigned int entries;
@ -80,31 +86,53 @@ static DEFINE_SPINLOCK(recent_lock);
static DEFINE_MUTEX(recent_mutex);
#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *proc_dir;
static const struct file_operations recent_fops;
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
static struct proc_dir_entry *proc_old_dir;
#endif
static struct proc_dir_entry *recent_proc_dir;
static const struct file_operations recent_old_fops, recent_mt_fops;
#endif
static u_int32_t hash_rnd;
static int hash_rnd_initted;
static bool hash_rnd_initted;
static unsigned int recent_entry_hash(__be32 addr)
static unsigned int recent_entry_hash4(const union nf_inet_addr *addr)
{
if (!hash_rnd_initted) {
get_random_bytes(&hash_rnd, 4);
hash_rnd_initted = 1;
get_random_bytes(&hash_rnd, sizeof(hash_rnd));
hash_rnd_initted = true;
}
return jhash_1word((__force u32)addr, hash_rnd) & (ip_list_hash_size - 1);
return jhash_1word((__force u32)addr->ip, hash_rnd) &
(ip_list_hash_size - 1);
}
static unsigned int recent_entry_hash6(const union nf_inet_addr *addr)
{
if (!hash_rnd_initted) {
get_random_bytes(&hash_rnd, sizeof(hash_rnd));
hash_rnd_initted = true;
}
return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) &
(ip_list_hash_size - 1);
}
static struct recent_entry *
recent_entry_lookup(const struct recent_table *table, __be32 addr, u_int8_t ttl)
recent_entry_lookup(const struct recent_table *table,
const union nf_inet_addr *addrp, u_int16_t family,
u_int8_t ttl)
{
struct recent_entry *e;
unsigned int h;
h = recent_entry_hash(addr);
if (family == AF_INET)
h = recent_entry_hash4(addrp);
else
h = recent_entry_hash6(addrp);
list_for_each_entry(e, &table->iphash[h], list)
if (e->addr == addr && (ttl == e->ttl || !ttl || !e->ttl))
if (e->family == family &&
memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 &&
(ttl == e->ttl || ttl == 0 || e->ttl == 0))
return e;
return NULL;
}
@ -118,7 +146,8 @@ static void recent_entry_remove(struct recent_table *t, struct recent_entry *e)
}
static struct recent_entry *
recent_entry_init(struct recent_table *t, __be32 addr, u_int8_t ttl)
recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr,
u_int16_t family, u_int8_t ttl)
{
struct recent_entry *e;
@ -130,12 +159,16 @@ recent_entry_init(struct recent_table *t, __be32 addr, u_int8_t ttl)
GFP_ATOMIC);
if (e == NULL)
return NULL;
e->addr = addr;
memcpy(&e->addr, addr, sizeof(e->addr));
e->ttl = ttl;
e->stamps[0] = jiffies;
e->nstamps = 1;
e->index = 1;
list_add_tail(&e->list, &t->iphash[recent_entry_hash(addr)]);
e->family = family;
if (family == AF_INET)
list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]);
else
list_add_tail(&e->list, &t->iphash[recent_entry_hash6(addr)]);
list_add_tail(&e->lru_list, &t->lru_list);
t->entries++;
return e;
@ -179,28 +212,42 @@ recent_mt(const struct sk_buff *skb, const struct net_device *in,
const struct xt_recent_mtinfo *info = matchinfo;
struct recent_table *t;
struct recent_entry *e;
__be32 addr;
union nf_inet_addr addr = {};
u_int8_t ttl;
bool ret = info->invert;
if (info->side == XT_RECENT_DEST)
addr = ip_hdr(skb)->daddr;
else
addr = ip_hdr(skb)->saddr;
if (match->family == AF_INET) {
const struct iphdr *iph = ip_hdr(skb);
if (info->side == XT_RECENT_DEST)
addr.ip = iph->daddr;
else
addr.ip = iph->saddr;
ttl = iph->ttl;
} else {
const struct ipv6hdr *iph = ipv6_hdr(skb);
if (info->side == XT_RECENT_DEST)
memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6));
else
memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6));
ttl = iph->hop_limit;
}
ttl = ip_hdr(skb)->ttl;
/* use TTL as seen before forwarding */
if (out && !skb->sk)
ttl++;
spin_lock_bh(&recent_lock);
t = recent_table_lookup(info->name);
e = recent_entry_lookup(t, addr,
info->check_set & XT_RECENT_TTL ? ttl : 0);
e = recent_entry_lookup(t, &addr, match->family,
(info->check_set & XT_RECENT_TTL) ? ttl : 0);
if (e == NULL) {
if (!(info->check_set & XT_RECENT_SET))
goto out;
e = recent_entry_init(t, addr, ttl);
e = recent_entry_init(t, &addr, match->family, ttl);
if (e == NULL)
*hotdrop = true;
ret = !ret;
@ -277,11 +324,24 @@ recent_mt_check(const char *tablename, const void *ip,
for (i = 0; i < ip_list_hash_size; i++)
INIT_LIST_HEAD(&t->iphash[i]);
#ifdef CONFIG_PROC_FS
t->proc = proc_create(t->name, ip_list_perms, proc_dir, &recent_fops);
t->proc = proc_create(t->name, ip_list_perms, recent_proc_dir,
&recent_mt_fops);
if (t->proc == NULL) {
kfree(t);
goto out;
}
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
t->proc_old = proc_create(t->name, ip_list_perms, proc_old_dir,
&recent_old_fops);
if (t->proc_old == NULL) {
remove_proc_entry(t->name, proc_old_dir);
kfree(t);
goto out;
}
t->proc_old->uid = ip_list_uid;
t->proc_old->gid = ip_list_gid;
t->proc_old->data = t;
#endif
t->proc->uid = ip_list_uid;
t->proc->gid = ip_list_gid;
t->proc->data = t;
@ -307,7 +367,10 @@ static void recent_mt_destroy(const struct xt_match *match, void *matchinfo)
list_del(&t->list);
spin_unlock_bh(&recent_lock);
#ifdef CONFIG_PROC_FS
remove_proc_entry(t->name, proc_dir);
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
remove_proc_entry(t->name, proc_old_dir);
#endif
remove_proc_entry(t->name, recent_proc_dir);
#endif
recent_table_flush(t);
kfree(t);
@ -317,7 +380,7 @@ static void recent_mt_destroy(const struct xt_match *match, void *matchinfo)
#ifdef CONFIG_PROC_FS
struct recent_iter_state {
struct recent_table *table;
const struct recent_table *table;
unsigned int bucket;
};
@ -342,8 +405,8 @@ static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct recent_iter_state *st = seq->private;
const struct recent_table *t = st->table;
struct recent_entry *e = v;
struct list_head *head = e->list.next;
const struct recent_entry *e = v;
const struct list_head *head = e->list.next;
while (head == &t->iphash[st->bucket]) {
if (++st->bucket >= ip_list_hash_size)
@ -366,8 +429,14 @@ static int recent_seq_show(struct seq_file *seq, void *v)
unsigned int i;
i = (e->index - 1) % ip_pkt_list_tot;
seq_printf(seq, "src=%u.%u.%u.%u ttl: %u last_seen: %lu oldest_pkt: %u",
NIPQUAD(e->addr), e->ttl, e->stamps[i], e->index);
if (e->family == AF_INET)
seq_printf(seq, "src=" NIPQUAD_FMT " ttl: %u last_seen: %lu "
"oldest_pkt: %u", NIPQUAD(e->addr.ip), e->ttl,
e->stamps[i], e->index);
else
seq_printf(seq, "src=" NIP6_FMT " ttl: %u last_seen: %lu "
"oldest_pkt: %u", NIP6(e->addr.in6), e->ttl,
e->stamps[i], e->index);
for (i = 0; i < e->nstamps; i++)
seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]);
seq_printf(seq, "\n");
@ -394,8 +463,22 @@ static int recent_seq_open(struct inode *inode, struct file *file)
return 0;
}
static ssize_t recent_proc_write(struct file *file, const char __user *input,
size_t size, loff_t *loff)
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
static int recent_old_seq_open(struct inode *inode, struct file *filp)
{
static bool warned_of_old;
if (unlikely(!warned_of_old)) {
printk(KERN_INFO KBUILD_MODNAME ": Use of /proc/net/ipt_recent"
" is deprecated; use /proc/net/xt_recent.\n");
warned_of_old = true;
}
return recent_seq_open(inode, filp);
}
static ssize_t recent_old_proc_write(struct file *file,
const char __user *input,
size_t size, loff_t *loff)
{
const struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
struct recent_table *t = pde->data;
@ -408,6 +491,7 @@ static ssize_t recent_proc_write(struct file *file, const char __user *input,
size = sizeof(buf);
if (copy_from_user(buf, input, size))
return -EFAULT;
while (isspace(*c))
c++;
@ -435,10 +519,10 @@ static ssize_t recent_proc_write(struct file *file, const char __user *input,
addr = in_aton(c);
spin_lock_bh(&recent_lock);
e = recent_entry_lookup(t, addr, 0);
e = recent_entry_lookup(t, (const void *)&addr, PF_INET, 0);
if (e == NULL) {
if (add)
recent_entry_init(t, addr, 0);
recent_entry_init(t, (const void *)&addr, PF_INET, 0);
} else {
if (add)
recent_entry_update(t, e);
@ -449,23 +533,118 @@ static ssize_t recent_proc_write(struct file *file, const char __user *input,
return size;
}
static const struct file_operations recent_fops = {
.open = recent_seq_open,
static const struct file_operations recent_old_fops = {
.open = recent_old_seq_open,
.read = seq_read,
.write = recent_proc_write,
.write = recent_old_proc_write,
.release = seq_release_private,
.owner = THIS_MODULE,
};
#endif
static ssize_t
recent_mt_proc_write(struct file *file, const char __user *input,
size_t size, loff_t *loff)
{
const struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
struct recent_table *t = pde->data;
struct recent_entry *e;
char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")];
const char *c = buf;
union nf_inet_addr addr;
u_int16_t family;
bool add, succ;
if (size == 0)
return 0;
if (size > sizeof(buf))
size = sizeof(buf);
if (copy_from_user(buf, input, size) != 0)
return -EFAULT;
/* Strict protocol! */
if (*loff != 0)
return -ESPIPE;
switch (*c) {
case '/': /* flush table */
spin_lock_bh(&recent_lock);
recent_table_flush(t);
spin_unlock_bh(&recent_lock);
return size;
case '-': /* remove address */
add = false;
break;
case '+': /* add address */
add = true;
break;
default:
printk(KERN_INFO KBUILD_MODNAME ": Need +ip, -ip or /\n");
return -EINVAL;
}
++c;
--size;
if (strnchr(c, size, ':') != NULL) {
family = AF_INET6;
succ = in6_pton(c, size, (void *)&addr, '\n', NULL);
} else {
family = AF_INET;
succ = in4_pton(c, size, (void *)&addr, '\n', NULL);
}
if (!succ) {
printk(KERN_INFO KBUILD_MODNAME ": illegal address written "
"to procfs\n");
return -EINVAL;
}
spin_lock_bh(&recent_lock);
e = recent_entry_lookup(t, &addr, family, 0);
if (e == NULL) {
if (add)
recent_entry_init(t, &addr, family, 0);
} else {
if (add)
recent_entry_update(t, e);
else
recent_entry_remove(t, e);
}
spin_unlock_bh(&recent_lock);
/* Note we removed one above */
*loff += size + 1;
return size + 1;
}
static const struct file_operations recent_mt_fops = {
.open = recent_seq_open,
.read = seq_read,
.write = recent_mt_proc_write,
.release = seq_release_private,
.owner = THIS_MODULE,
};
#endif /* CONFIG_PROC_FS */
static struct xt_match recent_mt_reg __read_mostly = {
.name = "recent",
.family = AF_INET,
.match = recent_mt,
.matchsize = sizeof(struct xt_recent_mtinfo),
.checkentry = recent_mt_check,
.destroy = recent_mt_destroy,
.me = THIS_MODULE,
static struct xt_match recent_mt_reg[] __read_mostly = {
{
.name = "recent",
.revision = 0,
.family = AF_INET,
.match = recent_mt,
.matchsize = sizeof(struct xt_recent_mtinfo),
.checkentry = recent_mt_check,
.destroy = recent_mt_destroy,
.me = THIS_MODULE,
},
{
.name = "recent",
.revision = 0,
.family = AF_INET6,
.match = recent_mt,
.matchsize = sizeof(struct xt_recent_mtinfo),
.checkentry = recent_mt_check,
.destroy = recent_mt_destroy,
.me = THIS_MODULE,
},
};
static int __init recent_mt_init(void)
@ -476,15 +655,25 @@ static int __init recent_mt_init(void)
return -EINVAL;
ip_list_hash_size = 1 << fls(ip_list_tot);
err = xt_register_match(&recent_mt_reg);
err = xt_register_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
#ifdef CONFIG_PROC_FS
if (err)
return err;
proc_dir = proc_mkdir("ipt_recent", init_net.proc_net);
if (proc_dir == NULL) {
xt_unregister_match(&recent_mt_reg);
recent_proc_dir = proc_mkdir("xt_recent", init_net.proc_net);
if (recent_proc_dir == NULL) {
xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
err = -ENOMEM;
}
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
if (err < 0)
return err;
proc_old_dir = proc_mkdir("ipt_recent", init_net.proc_net);
if (proc_old_dir == NULL) {
remove_proc_entry("xt_recent", init_net.proc_net);
xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
err = -ENOMEM;
}
#endif
#endif
return err;
}
@ -492,9 +681,12 @@ static int __init recent_mt_init(void)
static void __exit recent_mt_exit(void)
{
BUG_ON(!list_empty(&tables));
xt_unregister_match(&recent_mt_reg);
xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
#ifdef CONFIG_PROC_FS
#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT
remove_proc_entry("ipt_recent", init_net.proc_net);
#endif
remove_proc_entry("xt_recent", init_net.proc_net);
#endif
}