linux/net/netfilter/xt_string.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  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
  published by the free software foundation

  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
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

94 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* String matching match for iptables
*
* (C) 2005 Pablo Neira Ayuso <pablo@eurodev.net>
*/
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_string.h>
#include <linux/textsearch.h>
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@eurodev.net>");
MODULE_DESCRIPTION("Xtables: string-based matching");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_string");
MODULE_ALIAS("ip6t_string");
MODULE_ALIAS("ebt_string");
static bool
string_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
const struct xt_string_info *conf = par->matchinfo;
bool invert;
invert = conf->u.v1.flags & XT_STRING_FLAG_INVERT;
return (skb_find_text((struct sk_buff *)skb, conf->from_offset,
conf->to_offset, conf->config)
!= UINT_MAX) ^ invert;
}
#define STRING_TEXT_PRIV(m) ((struct xt_string_info *)(m))
static int string_mt_check(const struct xt_mtchk_param *par)
{
struct xt_string_info *conf = par->matchinfo;
struct ts_config *ts_conf;
int flags = TS_AUTOLOAD;
/* Damn, can't handle this case properly with iptables... */
if (conf->from_offset > conf->to_offset)
return -EINVAL;
if (conf->algo[XT_STRING_MAX_ALGO_NAME_SIZE - 1] != '\0')
return -EINVAL;
if (conf->patlen > XT_STRING_MAX_PATTERN_SIZE)
return -EINVAL;
if (conf->u.v1.flags &
~(XT_STRING_FLAG_IGNORECASE | XT_STRING_FLAG_INVERT))
return -EINVAL;
if (conf->u.v1.flags & XT_STRING_FLAG_IGNORECASE)
flags |= TS_IGNORECASE;
ts_conf = textsearch_prepare(conf->algo, conf->pattern, conf->patlen,
GFP_KERNEL, flags);
if (IS_ERR(ts_conf))
return PTR_ERR(ts_conf);
conf->config = ts_conf;
return 0;
}
static void string_mt_destroy(const struct xt_mtdtor_param *par)
{
textsearch_destroy(STRING_TEXT_PRIV(par->matchinfo)->config);
}
static struct xt_match xt_string_mt_reg __read_mostly = {
.name = "string",
.revision = 1,
.family = NFPROTO_UNSPEC,
.checkentry = string_mt_check,
.match = string_mt,
.destroy = string_mt_destroy,
.matchsize = sizeof(struct xt_string_info),
.usersize = offsetof(struct xt_string_info, config),
.me = THIS_MODULE,
};
static int __init string_mt_init(void)
{
return xt_register_match(&xt_string_mt_reg);
}
static void __exit string_mt_exit(void)
{
xt_unregister_match(&xt_string_mt_reg);
}
module_init(string_mt_init);
module_exit(string_mt_exit);