[deliverable/linux.git] / net / bridge / netfilter / ebt_log.c

/*
 *  ebt_log
 *
 *	Authors:
 *	Bart De Schuymer <bdschuym@pandora.be>
 *	Harald Welte <laforge@netfilter.org>
 *
 *  April, 2002
 *
 */
#include <linux/module.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/if_arp.h>
#include <linux/spinlock.h>
#include <net/netfilter/nf_log.h>
#include <linux/ipv6.h>
#include <net/ipv6.h>
#include <linux/in6.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_log.h>
#include <linux/netfilter.h>

static DEFINE_SPINLOCK(ebt_log_lock);

static int ebt_log_tg_check(const struct xt_tgchk_param *par)
{
	struct ebt_log_info *info = par->targinfo;

	if (info->bitmask & ~EBT_LOG_MASK)
		return -EINVAL;
	if (info->loglevel >= 8)
		return -EINVAL;
	info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
	return 0;
}

struct tcpudphdr {
	__be16 src;
	__be16 dst;
};

struct arppayload {
	unsigned char mac_src[ETH_ALEN];
	unsigned char ip_src[4];
	unsigned char mac_dst[ETH_ALEN];
	unsigned char ip_dst[4];
};

static void
print_ports(const struct sk_buff *skb, uint8_t protocol, int offset)
{
	if (protocol == IPPROTO_TCP ||
	    protocol == IPPROTO_UDP ||
	    protocol == IPPROTO_UDPLITE ||
	    protocol == IPPROTO_SCTP ||
	    protocol == IPPROTO_DCCP) {
		const struct tcpudphdr *pptr;
		struct tcpudphdr _ports;

		pptr = skb_header_pointer(skb, offset,
					  sizeof(_ports), &_ports);
		if (pptr == NULL) {
			printk(" INCOMPLETE TCP/UDP header");
			return;
		}
		printk(" SPT=%u DPT=%u", ntohs(pptr->src), ntohs(pptr->dst));
	}
}

static void
ebt_log_packet(struct net *net, u_int8_t pf, unsigned int hooknum,
	       const struct sk_buff *skb, const struct net_device *in,
	       const struct net_device *out, const struct nf_loginfo *loginfo,
	       const char *prefix)
{
	unsigned int bitmask;

	/* FIXME: Disabled from containers until syslog ns is supported */
	if (!net_eq(net, &init_net))
		return;

	spin_lock_bh(&ebt_log_lock);
	printk(KERN_SOH "%c%s IN=%s OUT=%s MAC source = %pM MAC dest = %pM proto = 0x%04x",
	       '0' + loginfo->u.log.level, prefix,
	       in ? in->name : "", out ? out->name : "",
	       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
	       ntohs(eth_hdr(skb)->h_proto));

	if (loginfo->type == NF_LOG_TYPE_LOG)
		bitmask = loginfo->u.log.logflags;
	else
		bitmask = NF_LOG_MASK;

	if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
	   htons(ETH_P_IP)) {
		const struct iphdr *ih;
		struct iphdr _iph;

		ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
		if (ih == NULL) {
			printk(" INCOMPLETE IP header");
			goto out;
		}
		printk(" IP SRC=%pI4 IP DST=%pI4, IP tos=0x%02X, IP proto=%d",
		       &ih->saddr, &ih->daddr, ih->tos, ih->protocol);
		print_ports(skb, ih->protocol, ih->ihl*4);
		goto out;
	}

#if IS_ENABLED(CONFIG_BRIDGE_EBT_IP6)
	if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto ==
	   htons(ETH_P_IPV6)) {
		const struct ipv6hdr *ih;
		struct ipv6hdr _iph;
		uint8_t nexthdr;
		__be16 frag_off;
		int offset_ph;

		ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
		if (ih == NULL) {
			printk(" INCOMPLETE IPv6 header");
			goto out;
		}
		printk(" IPv6 SRC=%pI6 IPv6 DST=%pI6, IPv6 priority=0x%01X, Next Header=%d",
		       &ih->saddr, &ih->daddr, ih->priority, ih->nexthdr);
		nexthdr = ih->nexthdr;
		offset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), &nexthdr, &frag_off);
		if (offset_ph == -1)
			goto out;
		print_ports(skb, nexthdr, offset_ph);
		goto out;
	}
#endif

	if ((bitmask & EBT_LOG_ARP) &&
	    ((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) ||
	     (eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
		const struct arphdr *ah;
		struct arphdr _arph;

		ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
		if (ah == NULL) {
			printk(" INCOMPLETE ARP header");
			goto out;
		}
		printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
		       ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
		       ntohs(ah->ar_op));

		/* If it's for Ethernet and the lengths are OK,
		 * then log the ARP payload
		 */
		if (ah->ar_hrd == htons(1) &&
		    ah->ar_hln == ETH_ALEN &&
		    ah->ar_pln == sizeof(__be32)) {
			const struct arppayload *ap;
			struct arppayload _arpp;

			ap = skb_header_pointer(skb, sizeof(_arph),
						sizeof(_arpp), &_arpp);
			if (ap == NULL) {
				printk(" INCOMPLETE ARP payload");
				goto out;
			}
			printk(" ARP MAC SRC=%pM ARP IP SRC=%pI4 ARP MAC DST=%pM ARP IP DST=%pI4",
					ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
		}
	}
out:
	printk("\n");
	spin_unlock_bh(&ebt_log_lock);

}

static unsigned int
ebt_log_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
	const struct ebt_log_info *info = par->targinfo;
	struct nf_loginfo li;
	struct net *net = par->net;

	li.type = NF_LOG_TYPE_LOG;
	li.u.log.level = info->loglevel;
	li.u.log.logflags = info->bitmask;

	/* Remember that we have to use ebt_log_packet() not to break backward
	 * compatibility. We cannot use the default bridge packet logger via
	 * nf_log_packet() with NFT_LOG_TYPE_LOG here. --Pablo
	 */
	if (info->bitmask & EBT_LOG_NFLOG)
		nf_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb,
			      par->in, par->out, &li, "%s", info->prefix);
	else
		ebt_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb, par->in,
			       par->out, &li, info->prefix);
	return EBT_CONTINUE;
}

static struct xt_target ebt_log_tg_reg __read_mostly = {
	.name		= "log",
	.revision	= 0,
	.family		= NFPROTO_BRIDGE,
	.target		= ebt_log_tg,
	.checkentry	= ebt_log_tg_check,
	.targetsize	= sizeof(struct ebt_log_info),
	.me		= THIS_MODULE,
};

static int __init ebt_log_init(void)
{
	return xt_register_target(&ebt_log_tg_reg);
}

static void __exit ebt_log_fini(void)
{
	xt_unregister_target(&ebt_log_tg_reg);
}

module_init(ebt_log_init);
module_exit(ebt_log_fini);
MODULE_DESCRIPTION("Ebtables: Packet logging to syslog");
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* ebt_log
	3	*
	4	* Authors:
	5	* Bart De Schuymer <bdschuym@pandora.be>
d5228a4f	6	* Harald Welte <laforge@netfilter.org>
1da177e4 LT	7	*
	8	* April, 2002
	9	*
	10	*/
1da177e4 LT	11	#include <linux/module.h>
1da177e4 LT	12	#include <linux/ip.h>
2e4e6a17	13	#include <linux/in.h>
1da177e4 LT	14	#include <linux/if_arp.h>
1da177e4 LT	15	#include <linux/spinlock.h>
f01ffbd6	16	#include <net/netfilter/nf_log.h>
93f65158 KT	17	#include <linux/ipv6.h>
	18	#include <net/ipv6.h>
	19	#include <linux/in6.h>
18219d3f JE	20	#include <linux/netfilter/x_tables.h>
	21	#include <linux/netfilter_bridge/ebtables.h>
	22	#include <linux/netfilter_bridge/ebt_log.h>
	23	#include <linux/netfilter.h>
1da177e4 LT	24
	25	static DEFINE_SPINLOCK(ebt_log_lock);
	26
135367b8	27	static int ebt_log_tg_check(const struct xt_tgchk_param *par)
1da177e4	28	{
af5d6dc2	29	struct ebt_log_info *info = par->targinfo;
1da177e4	30
1da177e4	31	if (info->bitmask & ~EBT_LOG_MASK)
d6b00a53	32	return -EINVAL;
1da177e4	33	if (info->loglevel >= 8)
d6b00a53	34	return -EINVAL;
1da177e4	35	info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
d6b00a53	36	return 0;
1da177e4 LT	37	}
1da177e4 LT	38
abcdd9a6	39	struct tcpudphdr {
47c183fa AV	40	__be16 src;
47c183fa AV	41	__be16 dst;
1da177e4 LT	42	};
1da177e4 LT	43
abcdd9a6	44	struct arppayload {
1da177e4 LT	45	unsigned char mac_src[ETH_ALEN];
	46	unsigned char ip_src[4];
	47	unsigned char mac_dst[ETH_ALEN];
	48	unsigned char ip_dst[4];
	49	};
	50
93f65158 KT	51	static void
	52	print_ports(const struct sk_buff *skb, uint8_t protocol, int offset)
	53	{
	54	if (protocol == IPPROTO_TCP \|\|
	55	protocol == IPPROTO_UDP \|\|
	56	protocol == IPPROTO_UDPLITE \|\|
	57	protocol == IPPROTO_SCTP \|\|
	58	protocol == IPPROTO_DCCP) {
	59	const struct tcpudphdr *pptr;
	60	struct tcpudphdr _ports;
	61
	62	pptr = skb_header_pointer(skb, offset,
	63	sizeof(_ports), &_ports);
	64	if (pptr == NULL) {
	65	printk(" INCOMPLETE TCP/UDP header");
	66	return;
	67	}
	68	printk(" SPT=%u DPT=%u", ntohs(pptr->src), ntohs(pptr->dst));
	69	}
	70	}
	71
d5228a4f	72	static void
8cdb46da HS	73	ebt_log_packet(struct net *net, u_int8_t pf, unsigned int hooknum,
	74	const struct sk_buff skb, const struct net_device in,
	75	const struct net_device out, const struct nf_loginfo loginfo,
	76	const char *prefix)
1da177e4	77	{
d5228a4f	78	unsigned int bitmask;
7d278924 G	79
	80	/* FIXME: Disabled from containers until syslog ns is supported */
	81	if (!net_eq(net, &init_net))
	82	return;
1da177e4	83
1da177e4	84	spin_lock_bh(&ebt_log_lock);
16af511a	85	printk(KERN_SOH "%c%s IN=%s OUT=%s MAC source = %pM MAC dest = %pM proto = 0x%04x",
be39ee11 TK	86	'0' + loginfo->u.log.level, prefix,
	87	in ? in->name : "", out ? out->name : "",
	88	eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
	89	ntohs(eth_hdr(skb)->h_proto));
1da177e4	90
d5228a4f BDS	91	if (loginfo->type == NF_LOG_TYPE_LOG)
	92	bitmask = loginfo->u.log.logflags;
	93	else
	94	bitmask = NF_LOG_MASK;
	95
	96	if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
31a5b837	97	htons(ETH_P_IP)) {
abfdf1c4 JE	98	const struct iphdr *ih;
abfdf1c4 JE	99	struct iphdr _iph;
1da177e4 LT	100
	101	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	102	if (ih == NULL) {
	103	printk(" INCOMPLETE IP header");
	104	goto out;
	105	}
21454aaa HH	106	printk(" IP SRC=%pI4 IP DST=%pI4, IP tos=0x%02X, IP proto=%d",
21454aaa HH	107	&ih->saddr, &ih->daddr, ih->tos, ih->protocol);
93f65158 KT	108	print_ports(skb, ih->protocol, ih->ihl*4);
	109	goto out;
	110	}
	111
e6373c4c	112	#if IS_ENABLED(CONFIG_BRIDGE_EBT_IP6)
93f65158 KT	113	if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto ==
	114	htons(ETH_P_IPV6)) {
	115	const struct ipv6hdr *ih;
	116	struct ipv6hdr _iph;
	117	uint8_t nexthdr;
75f2811c	118	__be16 frag_off;
93f65158 KT	119	int offset_ph;
	120
	121	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	122	if (ih == NULL) {
	123	printk(" INCOMPLETE IPv6 header");
	124	goto out;
1da177e4	125	}
5b095d98	126	printk(" IPv6 SRC=%pI6 IPv6 DST=%pI6, IPv6 priority=0x%01X, Next Header=%d",
b189db5d	127	&ih->saddr, &ih->daddr, ih->priority, ih->nexthdr);
93f65158	128	nexthdr = ih->nexthdr;
75f2811c	129	offset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), &nexthdr, &frag_off);
93f65158 KT	130	if (offset_ph == -1)
	131	goto out;
	132	print_ports(skb, nexthdr, offset_ph);
1da177e4 LT	133	goto out;
1da177e4 LT	134	}
f586287e	135	#endif
1da177e4	136
d5228a4f	137	if ((bitmask & EBT_LOG_ARP) &&
1da177e4 LT	138	((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) \|\|
1da177e4 LT	139	(eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
abfdf1c4 JE	140	const struct arphdr *ah;
abfdf1c4 JE	141	struct arphdr _arph;
1da177e4 LT	142
	143	ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
	144	if (ah == NULL) {
	145	printk(" INCOMPLETE ARP header");
	146	goto out;
	147	}
	148	printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
	149	ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
	150	ntohs(ah->ar_op));
	151
	152	/* If it's for Ethernet and the lengths are OK,
7f495ad9 IM	153	* then log the ARP payload
7f495ad9 IM	154	*/
1da177e4 LT	155	if (ah->ar_hrd == htons(1) &&
1da177e4 LT	156	ah->ar_hln == ETH_ALEN &&
47c183fa	157	ah->ar_pln == sizeof(__be32)) {
abfdf1c4 JE	158	const struct arppayload *ap;
abfdf1c4 JE	159	struct arppayload _arpp;
1da177e4	160
85c1937b	161	ap = skb_header_pointer(skb, sizeof(_arph),
1da177e4 LT	162	sizeof(_arpp), &_arpp);
	163	if (ap == NULL) {
	164	printk(" INCOMPLETE ARP payload");
	165	goto out;
	166	}
be39ee11 TK	167	printk(" ARP MAC SRC=%pM ARP IP SRC=%pI4 ARP MAC DST=%pM ARP IP DST=%pI4",
be39ee11 TK	168	ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
1da177e4 LT	169	}
	170	}
	171	out:
	172	printk("\n");
	173	spin_unlock_bh(&ebt_log_lock);
d5228a4f BDS	174
	175	}
	176
2d06d4a5	177	static unsigned int
4b560b44	178	ebt_log_tg(struct sk_buff skb, const struct xt_action_param par)
d5228a4f	179	{
7eb35586	180	const struct ebt_log_info *info = par->targinfo;
d5228a4f	181	struct nf_loginfo li;
686c9b50	182	struct net *net = par->net;
d5228a4f BDS	183
	184	li.type = NF_LOG_TYPE_LOG;
	185	li.u.log.level = info->loglevel;
	186	li.u.log.logflags = info->bitmask;
	187
960649d1 PNA	188	/* Remember that we have to use ebt_log_packet() not to break backward
	189	* compatibility. We cannot use the default bridge packet logger via
	190	* nf_log_packet() with NFT_LOG_TYPE_LOG here. --Pablo
	191	*/
bafac2a5	192	if (info->bitmask & EBT_LOG_NFLOG)
30e0c6a6 G	193	nf_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb,
30e0c6a6 G	194	par->in, par->out, &li, "%s", info->prefix);
bafac2a5	195	else
8cdb46da	196	ebt_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb, par->in,
30e0c6a6	197	par->out, &li, info->prefix);
0ac6ab1f	198	return EBT_CONTINUE;
1da177e4 LT	199	}
1da177e4 LT	200
043ef46c JE	201	static struct xt_target ebt_log_tg_reg __read_mostly = {
043ef46c JE	202	.name = "log",
001a18d3 JE	203	.revision = 0,
001a18d3 JE	204	.family = NFPROTO_BRIDGE,
2d06d4a5 JE	205	.target = ebt_log_tg,
2d06d4a5 JE	206	.checkentry = ebt_log_tg_check,
fc0e3df4	207	.targetsize = sizeof(struct ebt_log_info),
1da177e4 LT	208	.me = THIS_MODULE,
	209	};
	210
65b4b4e8	211	static int __init ebt_log_init(void)
1da177e4	212	{
960649d1	213	return xt_register_target(&ebt_log_tg_reg);
1da177e4 LT	214	}
1da177e4 LT	215
65b4b4e8	216	static void __exit ebt_log_fini(void)
1da177e4	217	{
043ef46c	218	xt_unregister_target(&ebt_log_tg_reg);
1da177e4 LT	219	}
1da177e4 LT	220
65b4b4e8 AM	221	module_init(ebt_log_init);
65b4b4e8 AM	222	module_exit(ebt_log_fini);
f776c4cd	223	MODULE_DESCRIPTION("Ebtables: Packet logging to syslog");
1da177e4	224	MODULE_LICENSE("GPL");