[mirror_ubuntu-zesty-kernel.git] / net / netfilter / nft_log.c

/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 * Copyright (c) 2012-2014 Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * 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.
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_log.h>
#include <linux/netdevice.h>

static const char *nft_log_null_prefix = "";

struct nft_log {
	struct nf_loginfo	loginfo;
	char			*prefix;
};

static void nft_log_eval(const struct nft_expr *expr,
			 struct nft_regs *regs,
			 const struct nft_pktinfo *pkt)
{
	const struct nft_log *priv = nft_expr_priv(expr);

	nf_log_packet(pkt->net, pkt->pf, pkt->hook, pkt->skb, pkt->in,
		      pkt->out, &priv->loginfo, "%s", priv->prefix);
}

static const struct nla_policy nft_log_policy[NFTA_LOG_MAX + 1] = {
	[NFTA_LOG_GROUP]	= { .type = NLA_U16 },
	[NFTA_LOG_PREFIX]	= { .type = NLA_STRING },
	[NFTA_LOG_SNAPLEN]	= { .type = NLA_U32 },
	[NFTA_LOG_QTHRESHOLD]	= { .type = NLA_U16 },
	[NFTA_LOG_LEVEL]	= { .type = NLA_U32 },
	[NFTA_LOG_FLAGS]	= { .type = NLA_U32 },
};

static int nft_log_init(const struct nft_ctx *ctx,
			const struct nft_expr *expr,
			const struct nlattr * const tb[])
{
	struct nft_log *priv = nft_expr_priv(expr);
	struct nf_loginfo *li = &priv->loginfo;
	const struct nlattr *nla;
	int err;

	li->type = NF_LOG_TYPE_LOG;
	if (tb[NFTA_LOG_LEVEL] != NULL &&
	    tb[NFTA_LOG_GROUP] != NULL)
		return -EINVAL;
	if (tb[NFTA_LOG_GROUP] != NULL) {
		li->type = NF_LOG_TYPE_ULOG;
		if (tb[NFTA_LOG_FLAGS] != NULL)
			return -EINVAL;
	}

	nla = tb[NFTA_LOG_PREFIX];
	if (nla != NULL) {
		priv->prefix = kmalloc(nla_len(nla) + 1, GFP_KERNEL);
		if (priv->prefix == NULL)
			return -ENOMEM;
		nla_strlcpy(priv->prefix, nla, nla_len(nla) + 1);
	} else {
		priv->prefix = (char *)nft_log_null_prefix;
	}

	switch (li->type) {
	case NF_LOG_TYPE_LOG:
		if (tb[NFTA_LOG_LEVEL] != NULL) {
			li->u.log.level =
				ntohl(nla_get_be32(tb[NFTA_LOG_LEVEL]));
		} else {
			li->u.log.level = LOGLEVEL_WARNING;
		}
		if (li->u.log.level > LOGLEVEL_DEBUG) {
			err = -EINVAL;
			goto err1;
		}

		if (tb[NFTA_LOG_FLAGS] != NULL) {
			li->u.log.logflags =
				ntohl(nla_get_be32(tb[NFTA_LOG_FLAGS]));
			if (li->u.log.logflags & ~NF_LOG_MASK) {
				err = -EINVAL;
				goto err1;
			}
		}
		break;
	case NF_LOG_TYPE_ULOG:
		li->u.ulog.group = ntohs(nla_get_be16(tb[NFTA_LOG_GROUP]));
		if (tb[NFTA_LOG_SNAPLEN] != NULL) {
			li->u.ulog.flags |= NF_LOG_F_COPY_LEN;
			li->u.ulog.copy_len =
				ntohl(nla_get_be32(tb[NFTA_LOG_SNAPLEN]));
		}
		if (tb[NFTA_LOG_QTHRESHOLD] != NULL) {
			li->u.ulog.qthreshold =
				ntohs(nla_get_be16(tb[NFTA_LOG_QTHRESHOLD]));
		}
		break;
	}

	err = nf_logger_find_get(ctx->afi->family, li->type);
	if (err < 0)
		goto err1;

	return 0;

err1:
	if (priv->prefix != nft_log_null_prefix)
		kfree(priv->prefix);
	return err;
}

static void nft_log_destroy(const struct nft_ctx *ctx,
			    const struct nft_expr *expr)
{
	struct nft_log *priv = nft_expr_priv(expr);
	struct nf_loginfo *li = &priv->loginfo;

	if (priv->prefix != nft_log_null_prefix)
		kfree(priv->prefix);

	nf_logger_put(ctx->afi->family, li->type);
}

static int nft_log_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_log *priv = nft_expr_priv(expr);
	const struct nf_loginfo *li = &priv->loginfo;

	if (priv->prefix != nft_log_null_prefix)
		if (nla_put_string(skb, NFTA_LOG_PREFIX, priv->prefix))
			goto nla_put_failure;
	switch (li->type) {
	case NF_LOG_TYPE_LOG:
		if (nla_put_be32(skb, NFTA_LOG_LEVEL, htonl(li->u.log.level)))
			goto nla_put_failure;

		if (li->u.log.logflags) {
			if (nla_put_be32(skb, NFTA_LOG_FLAGS,
					 htonl(li->u.log.logflags)))
				goto nla_put_failure;
		}
		break;
	case NF_LOG_TYPE_ULOG:
		if (nla_put_be16(skb, NFTA_LOG_GROUP, htons(li->u.ulog.group)))
			goto nla_put_failure;

		if (li->u.ulog.flags & NF_LOG_F_COPY_LEN) {
			if (nla_put_be32(skb, NFTA_LOG_SNAPLEN,
					 htonl(li->u.ulog.copy_len)))
				goto nla_put_failure;
		}
		if (li->u.ulog.qthreshold) {
			if (nla_put_be16(skb, NFTA_LOG_QTHRESHOLD,
					 htons(li->u.ulog.qthreshold)))
				goto nla_put_failure;
		}
		break;
	}
	return 0;

nla_put_failure:
	return -1;
}

static struct nft_expr_type nft_log_type;
static const struct nft_expr_ops nft_log_ops = {
	.type		= &nft_log_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_log)),
	.eval		= nft_log_eval,
	.init		= nft_log_init,
	.destroy	= nft_log_destroy,
	.dump		= nft_log_dump,
};

static struct nft_expr_type nft_log_type __read_mostly = {
	.name		= "log",
	.ops		= &nft_log_ops,
	.policy		= nft_log_policy,
	.maxattr	= NFTA_LOG_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_log_module_init(void)
{
	return nft_register_expr(&nft_log_type);
}

static void __exit nft_log_module_exit(void)
{
	nft_unregister_expr(&nft_log_type);
}

module_init(nft_log_module_init);
module_exit(nft_log_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_EXPR("log");
Commit	Line	Data
96518518	1	/*
ef1f7df9	2	* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
09d27b88	3	* Copyright (c) 2012-2014 Pablo Neira Ayuso <pablo@netfilter.org>
96518518 PM	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	* Development of this code funded by Astaro AG (http://www.astaro.com/)
	10	*/
	11
	12	#include <linux/kernel.h>
	13	#include <linux/init.h>
	14	#include <linux/module.h>
	15	#include <linux/netlink.h>
	16	#include <linux/netfilter.h>
	17	#include <linux/netfilter/nf_tables.h>
	18	#include <net/netfilter/nf_tables.h>
	19	#include <net/netfilter/nf_log.h>
	20	#include <linux/netdevice.h>
	21
	22	static const char *nft_log_null_prefix = "";
	23
	24	struct nft_log {
	25	struct nf_loginfo loginfo;
	26	char *prefix;
96518518 PM	27	};
	28
	29	static void nft_log_eval(const struct nft_expr *expr,
a55e22e9	30	struct nft_regs *regs,
96518518 PM	31	const struct nft_pktinfo *pkt)
	32	{
	33	const struct nft_log *priv = nft_expr_priv(expr);
96518518	34
88182a0e	35	nf_log_packet(pkt->net, pkt->pf, pkt->hook, pkt->skb, pkt->in,
96518518 PM	36	pkt->out, &priv->loginfo, "%s", priv->prefix);
	37	}
	38
	39	static const struct nla_policy nft_log_policy[NFTA_LOG_MAX + 1] = {
	40	[NFTA_LOG_GROUP] = { .type = NLA_U16 },
	41	[NFTA_LOG_PREFIX] = { .type = NLA_STRING },
	42	[NFTA_LOG_SNAPLEN] = { .type = NLA_U32 },
	43	[NFTA_LOG_QTHRESHOLD] = { .type = NLA_U16 },
09d27b88 PNA	44	[NFTA_LOG_LEVEL] = { .type = NLA_U32 },
09d27b88 PNA	45	[NFTA_LOG_FLAGS] = { .type = NLA_U32 },
96518518 PM	46	};
	47
	48	static int nft_log_init(const struct nft_ctx *ctx,
	49	const struct nft_expr *expr,
	50	const struct nlattr * const tb[])
	51	{
	52	struct nft_log *priv = nft_expr_priv(expr);
	53	struct nf_loginfo *li = &priv->loginfo;
	54	const struct nlattr *nla;
c2d9a429 LZ	55	int err;
	56
	57	li->type = NF_LOG_TYPE_LOG;
	58	if (tb[NFTA_LOG_LEVEL] != NULL &&
	59	tb[NFTA_LOG_GROUP] != NULL)
	60	return -EINVAL;
ff107d27	61	if (tb[NFTA_LOG_GROUP] != NULL) {
c2d9a429	62	li->type = NF_LOG_TYPE_ULOG;
ff107d27 LZ	63	if (tb[NFTA_LOG_FLAGS] != NULL)
	64	return -EINVAL;
	65	}
96518518	66
96518518 PM	67	nla = tb[NFTA_LOG_PREFIX];
	68	if (nla != NULL) {
	69	priv->prefix = kmalloc(nla_len(nla) + 1, GFP_KERNEL);
	70	if (priv->prefix == NULL)
	71	return -ENOMEM;
	72	nla_strlcpy(priv->prefix, nla, nla_len(nla) + 1);
09d27b88	73	} else {
96518518	74	priv->prefix = (char *)nft_log_null_prefix;
09d27b88	75	}
96518518	76
09d27b88 PNA	77	switch (li->type) {
	78	case NF_LOG_TYPE_LOG:
	79	if (tb[NFTA_LOG_LEVEL] != NULL) {
	80	li->u.log.level =
5cbfda20	81	ntohl(nla_get_be32(tb[NFTA_LOG_LEVEL]));
09d27b88	82	} else {
a81b2ce8	83	li->u.log.level = LOGLEVEL_WARNING;
09d27b88	84	}
1bc4e013 LZ	85	if (li->u.log.level > LOGLEVEL_DEBUG) {
	86	err = -EINVAL;
	87	goto err1;
	88	}
	89
09d27b88 PNA	90	if (tb[NFTA_LOG_FLAGS] != NULL) {
	91	li->u.log.logflags =
	92	ntohl(nla_get_be32(tb[NFTA_LOG_FLAGS]));
ff107d27 LZ	93	if (li->u.log.logflags & ~NF_LOG_MASK) {
	94	err = -EINVAL;
	95	goto err1;
	96	}
09d27b88 PNA	97	}
	98	break;
	99	case NF_LOG_TYPE_ULOG:
96518518	100	li->u.ulog.group = ntohs(nla_get_be16(tb[NFTA_LOG_GROUP]));
09d27b88	101	if (tb[NFTA_LOG_SNAPLEN] != NULL) {
cc37c1ad	102	li->u.ulog.flags \|= NF_LOG_F_COPY_LEN;
09d27b88 PNA	103	li->u.ulog.copy_len =
	104	ntohl(nla_get_be32(tb[NFTA_LOG_SNAPLEN]));
	105	}
	106	if (tb[NFTA_LOG_QTHRESHOLD] != NULL) {
	107	li->u.ulog.qthreshold =
	108	ntohs(nla_get_be16(tb[NFTA_LOG_QTHRESHOLD]));
	109	}
	110	break;
96518518 PM	111	}
96518518 PM	112
c2d9a429 LZ	113	err = nf_logger_find_get(ctx->afi->family, li->type);
	114	if (err < 0)
	115	goto err1;
	116
	117	return 0;
	118
	119	err1:
	120	if (priv->prefix != nft_log_null_prefix)
	121	kfree(priv->prefix);
	122	return err;
96518518 PM	123	}
96518518 PM	124
62472bce PM	125	static void nft_log_destroy(const struct nft_ctx *ctx,
62472bce PM	126	const struct nft_expr *expr)
96518518 PM	127	{
96518518 PM	128	struct nft_log *priv = nft_expr_priv(expr);
85d30e24	129	struct nf_loginfo *li = &priv->loginfo;
96518518 PM	130
	131	if (priv->prefix != nft_log_null_prefix)
	132	kfree(priv->prefix);
85d30e24	133
f3bb5333	134	nf_logger_put(ctx->afi->family, li->type);
96518518 PM	135	}
	136
	137	static int nft_log_dump(struct sk_buff skb, const struct nft_expr expr)
	138	{
	139	const struct nft_log *priv = nft_expr_priv(expr);
	140	const struct nf_loginfo *li = &priv->loginfo;
	141
	142	if (priv->prefix != nft_log_null_prefix)
	143	if (nla_put_string(skb, NFTA_LOG_PREFIX, priv->prefix))
	144	goto nla_put_failure;
09d27b88 PNA	145	switch (li->type) {
	146	case NF_LOG_TYPE_LOG:
	147	if (nla_put_be32(skb, NFTA_LOG_LEVEL, htonl(li->u.log.level)))
96518518	148	goto nla_put_failure;
09d27b88 PNA	149
	150	if (li->u.log.logflags) {
	151	if (nla_put_be32(skb, NFTA_LOG_FLAGS,
	152	htonl(li->u.log.logflags)))
	153	goto nla_put_failure;
	154	}
	155	break;
	156	case NF_LOG_TYPE_ULOG:
	157	if (nla_put_be16(skb, NFTA_LOG_GROUP, htons(li->u.ulog.group)))
96518518	158	goto nla_put_failure;
09d27b88	159
cc37c1ad	160	if (li->u.ulog.flags & NF_LOG_F_COPY_LEN) {
09d27b88 PNA	161	if (nla_put_be32(skb, NFTA_LOG_SNAPLEN,
	162	htonl(li->u.ulog.copy_len)))
	163	goto nla_put_failure;
	164	}
	165	if (li->u.ulog.qthreshold) {
	166	if (nla_put_be16(skb, NFTA_LOG_QTHRESHOLD,
	167	htons(li->u.ulog.qthreshold)))
	168	goto nla_put_failure;
	169	}
	170	break;
	171	}
96518518 PM	172	return 0;
	173
	174	nla_put_failure:
	175	return -1;
	176	}
	177
ef1f7df9 PM	178	static struct nft_expr_type nft_log_type;
	179	static const struct nft_expr_ops nft_log_ops = {
	180	.type = &nft_log_type,
96518518	181	.size = NFT_EXPR_SIZE(sizeof(struct nft_log)),
96518518 PM	182	.eval = nft_log_eval,
	183	.init = nft_log_init,
	184	.destroy = nft_log_destroy,
	185	.dump = nft_log_dump,
ef1f7df9 PM	186	};
	187
	188	static struct nft_expr_type nft_log_type __read_mostly = {
	189	.name = "log",
	190	.ops = &nft_log_ops,
96518518 PM	191	.policy = nft_log_policy,
96518518 PM	192	.maxattr = NFTA_LOG_MAX,
ef1f7df9	193	.owner = THIS_MODULE,
96518518 PM	194	};
	195
	196	static int __init nft_log_module_init(void)
	197	{
ef1f7df9	198	return nft_register_expr(&nft_log_type);
96518518 PM	199	}
	200
	201	static void __exit nft_log_module_exit(void)
	202	{
ef1f7df9	203	nft_unregister_expr(&nft_log_type);
96518518 PM	204	}
	205
	206	module_init(nft_log_module_init);
	207	module_exit(nft_log_module_exit);
	208
	209	MODULE_LICENSE("GPL");
	210	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	211	MODULE_ALIAS_NFT_EXPR("log");