diff options
Diffstat (limited to 'net/netfilter/xt_bpf.c')
| -rw-r--r-- | net/netfilter/xt_bpf.c | 74 | 
1 files changed, 74 insertions, 0 deletions
diff --git a/net/netfilter/xt_bpf.c b/net/netfilter/xt_bpf.c new file mode 100644 index 00000000000..bbffdbdaf60 --- /dev/null +++ b/net/netfilter/xt_bpf.c @@ -0,0 +1,74 @@ +/* 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/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(const struct xt_mtchk_param *par) +{ +	struct xt_bpf_info *info = par->matchinfo; +	struct sock_fprog_kern program; + +	program.len = info->bpf_program_num_elem; +	program.filter = info->bpf_program; + +	if (sk_unattached_filter_create(&info->filter, &program)) { +		pr_info("bpf: check failed: parse error\n"); +		return -EINVAL; +	} + +	return 0; +} + +static bool bpf_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ +	const struct xt_bpf_info *info = par->matchinfo; + +	return SK_RUN_FILTER(info->filter, skb); +} + +static void bpf_mt_destroy(const struct xt_mtdtor_param *par) +{ +	const struct xt_bpf_info *info = par->matchinfo; +	sk_unattached_filter_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), +	.me		= THIS_MODULE, +}; + +static int __init bpf_mt_init(void) +{ +	return xt_register_match(&bpf_mt_reg); +} + +static void __exit bpf_mt_exit(void) +{ +	xt_unregister_match(&bpf_mt_reg); +} + +module_init(bpf_mt_init); +module_exit(bpf_mt_exit);  | 
