[mirror_ubuntu-artful-kernel.git] / net / netfilter / xt_bpf.c

/* Xtables module to match packets using a BPF filter.
 * Copyright 2013 Google Inc.
 * Written by Willem de Bruijn <willemb@google.com>
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/filter.h>
#include <linux/bpf.h>

#include <linux/netfilter/xt_bpf.h>
#include <linux/netfilter/x_tables.h>

MODULE_AUTHOR("Willem de Bruijn <willemb@google.com>");
MODULE_DESCRIPTION("Xtables: BPF filter match");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_bpf");
MODULE_ALIAS("ip6t_bpf");

static int __bpf_mt_check_bytecode(struct sock_filter *insns, __u16 len,
				   struct bpf_prog **ret)
{
	struct sock_fprog_kern program;

	program.len = len;
	program.filter = insns;

	if (bpf_prog_create(ret, &program)) {
		pr_info("bpf: check failed: parse error\n");
		return -EINVAL;
	}

	return 0;
}

static int __bpf_mt_check_fd(int fd, struct bpf_prog **ret)
{
	struct bpf_prog *prog;

	prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	*ret = prog;
	return 0;
}

static int bpf_mt_check(const struct xt_mtchk_param *par)
{
	struct xt_bpf_info *info = par->matchinfo;

	return __bpf_mt_check_bytecode(info->bpf_program,
				       info->bpf_program_num_elem,
				       &info->filter);
}

static int bpf_mt_check_v1(const struct xt_mtchk_param *par)
{
	struct xt_bpf_info_v1 *info = par->matchinfo;

	if (info->mode == XT_BPF_MODE_BYTECODE)
		return __bpf_mt_check_bytecode(info->bpf_program,
					       info->bpf_program_num_elem,
					       &info->filter);
	else if (info->mode == XT_BPF_MODE_FD_PINNED ||
		 info->mode == XT_BPF_MODE_FD_ELF)
		return __bpf_mt_check_fd(info->fd, &info->filter);
	else
		return -EINVAL;
}

static bool bpf_mt(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct xt_bpf_info *info = par->matchinfo;

	return BPF_PROG_RUN(info->filter, skb);
}

static bool bpf_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct xt_bpf_info_v1 *info = par->matchinfo;

	return !!bpf_prog_run_save_cb(info->filter, (struct sk_buff *) skb);
}

static void bpf_mt_destroy(const struct xt_mtdtor_param *par)
{
	const struct xt_bpf_info *info = par->matchinfo;

	bpf_prog_destroy(info->filter);
}

static void bpf_mt_destroy_v1(const struct xt_mtdtor_param *par)
{
	const struct xt_bpf_info_v1 *info = par->matchinfo;

	bpf_prog_destroy(info->filter);
}

static struct xt_match bpf_mt_reg[] __read_mostly = {
	{
		.name		= "bpf",
		.revision	= 0,
		.family		= NFPROTO_UNSPEC,
		.checkentry	= bpf_mt_check,
		.match		= bpf_mt,
		.destroy	= bpf_mt_destroy,
		.matchsize	= sizeof(struct xt_bpf_info),
		.usersize	= offsetof(struct xt_bpf_info, filter),
		.me		= THIS_MODULE,
	},
	{
		.name		= "bpf",
		.revision	= 1,
		.family		= NFPROTO_UNSPEC,
		.checkentry	= bpf_mt_check_v1,
		.match		= bpf_mt_v1,
		.destroy	= bpf_mt_destroy_v1,
		.matchsize	= sizeof(struct xt_bpf_info_v1),
		.usersize	= offsetof(struct xt_bpf_info_v1, filter),
		.me		= THIS_MODULE,
	},
};

static int __init bpf_mt_init(void)
{
	return xt_register_matches(bpf_mt_reg, ARRAY_SIZE(bpf_mt_reg));
}

static void __exit bpf_mt_exit(void)
{
	xt_unregister_matches(bpf_mt_reg, ARRAY_SIZE(bpf_mt_reg));
}

module_init(bpf_mt_init);
module_exit(bpf_mt_exit);
Commit	Line	Data
e6f30c73 WB	1	/* Xtables module to match packets using a BPF filter.
	2	* Copyright 2013 Google Inc.
	3	* Written by Willem de Bruijn <willemb@google.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/skbuff.h>
	12	#include <linux/filter.h>
2c16d603	13	#include <linux/bpf.h>
e6f30c73 WB	14
	15	#include <linux/netfilter/xt_bpf.h>
	16	#include <linux/netfilter/x_tables.h>
	17
	18	MODULE_AUTHOR("Willem de Bruijn <willemb@google.com>");
	19	MODULE_DESCRIPTION("Xtables: BPF filter match");
	20	MODULE_LICENSE("GPL");
	21	MODULE_ALIAS("ipt_bpf");
	22	MODULE_ALIAS("ip6t_bpf");
	23
2c16d603 WB	24	static int __bpf_mt_check_bytecode(struct sock_filter *insns, __u16 len,
2c16d603 WB	25	struct bpf_prog **ret)
e6f30c73	26	{
b1fcd35c	27	struct sock_fprog_kern program;
e6f30c73	28
2c16d603 WB	29	program.len = len;
2c16d603 WB	30	program.filter = insns;
b1fcd35c	31
2c16d603	32	if (bpf_prog_create(ret, &program)) {
e6f30c73 WB	33	pr_info("bpf: check failed: parse error\n");
	34	return -EINVAL;
	35	}
	36
	37	return 0;
	38	}
	39
2c16d603 WB	40	static int __bpf_mt_check_fd(int fd, struct bpf_prog **ret)
	41	{
	42	struct bpf_prog *prog;
	43
	44	prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
	45	if (IS_ERR(prog))
	46	return PTR_ERR(prog);
	47
	48	*ret = prog;
	49	return 0;
	50	}
	51
	52	static int bpf_mt_check(const struct xt_mtchk_param *par)
	53	{
	54	struct xt_bpf_info *info = par->matchinfo;
	55
	56	return __bpf_mt_check_bytecode(info->bpf_program,
	57	info->bpf_program_num_elem,
	58	&info->filter);
	59	}
	60
	61	static int bpf_mt_check_v1(const struct xt_mtchk_param *par)
	62	{
	63	struct xt_bpf_info_v1 *info = par->matchinfo;
	64
	65	if (info->mode == XT_BPF_MODE_BYTECODE)
	66	return __bpf_mt_check_bytecode(info->bpf_program,
	67	info->bpf_program_num_elem,
	68	&info->filter);
	69	else if (info->mode == XT_BPF_MODE_FD_PINNED \|\|
	70	info->mode == XT_BPF_MODE_FD_ELF)
	71	return __bpf_mt_check_fd(info->fd, &info->filter);
	72	else
	73	return -EINVAL;
	74	}
	75
e6f30c73 WB	76	static bool bpf_mt(const struct sk_buff skb, struct xt_action_param par)
	77	{
	78	const struct xt_bpf_info *info = par->matchinfo;
	79
7ae457c1	80	return BPF_PROG_RUN(info->filter, skb);
e6f30c73 WB	81	}
e6f30c73 WB	82
2c16d603 WB	83	static bool bpf_mt_v1(const struct sk_buff skb, struct xt_action_param par)
	84	{
	85	const struct xt_bpf_info_v1 *info = par->matchinfo;
	86
	87	return !!bpf_prog_run_save_cb(info->filter, (struct sk_buff *) skb);
	88	}
	89
e6f30c73 WB	90	static void bpf_mt_destroy(const struct xt_mtdtor_param *par)
	91	{
	92	const struct xt_bpf_info *info = par->matchinfo;
2c16d603 WB	93
	94	bpf_prog_destroy(info->filter);
	95	}
	96
	97	static void bpf_mt_destroy_v1(const struct xt_mtdtor_param *par)
	98	{
	99	const struct xt_bpf_info_v1 *info = par->matchinfo;
	100
7ae457c1	101	bpf_prog_destroy(info->filter);
e6f30c73 WB	102	}
e6f30c73 WB	103
2c16d603 WB	104	static struct xt_match bpf_mt_reg[] __read_mostly = {
	105	{
	106	.name = "bpf",
	107	.revision = 0,
	108	.family = NFPROTO_UNSPEC,
	109	.checkentry = bpf_mt_check,
	110	.match = bpf_mt,
	111	.destroy = bpf_mt_destroy,
	112	.matchsize = sizeof(struct xt_bpf_info),
ec231890	113	.usersize = offsetof(struct xt_bpf_info, filter),
2c16d603 WB	114	.me = THIS_MODULE,
	115	},
	116	{
	117	.name = "bpf",
	118	.revision = 1,
	119	.family = NFPROTO_UNSPEC,
	120	.checkentry = bpf_mt_check_v1,
	121	.match = bpf_mt_v1,
	122	.destroy = bpf_mt_destroy_v1,
	123	.matchsize = sizeof(struct xt_bpf_info_v1),
ec231890	124	.usersize = offsetof(struct xt_bpf_info_v1, filter),
2c16d603 WB	125	.me = THIS_MODULE,
2c16d603 WB	126	},
e6f30c73 WB	127	};
	128
	129	static int __init bpf_mt_init(void)
	130	{
2c16d603	131	return xt_register_matches(bpf_mt_reg, ARRAY_SIZE(bpf_mt_reg));
e6f30c73 WB	132	}
	133
	134	static void __exit bpf_mt_exit(void)
	135	{
2c16d603	136	xt_unregister_matches(bpf_mt_reg, ARRAY_SIZE(bpf_mt_reg));
e6f30c73 WB	137	}
	138
	139	module_init(bpf_mt_init);
	140	module_exit(bpf_mt_exit);