[linux-block.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 bool ebt_log_tg_check(const struct xt_tgchk_param *par)
{
	struct ebt_log_info *info = par->targinfo;

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

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_MAC(const unsigned char *p)
{
	int i;

	for (i = 0; i < ETH_ALEN; i++, p++)
		printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
}

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(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;

	spin_lock_bh(&ebt_log_lock);
	printk("<%c>%s IN=%s OUT=%s MAC source = ", '0' + loginfo->u.log.level,
	       prefix, in ? in->name : "", out ? out->name : "");

	print_MAC(eth_hdr(skb)->h_source);
	printk("MAC dest = ");
	print_MAC(eth_hdr(skb)->h_dest);

	printk("proto = 0x%04x", 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 defined(CONFIG_BRIDGE_EBT_IP6) || defined(CONFIG_BRIDGE_EBT_IP6_MODULE)
	if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto ==
	   htons(ETH_P_IPV6)) {
		const struct ipv6hdr *ih;
		struct ipv6hdr _iph;
		uint8_t nexthdr;
		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);
		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=");
			print_MAC(ap->mac_src);
			printk(" ARP IP SRC=%pI4", ap->ip_src);
			printk(" ARP MAC DST=");
			print_MAC(ap->mac_dst);
			printk(" ARP IP DST=%pI4", 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_target_param *par)
{
	const struct ebt_log_info *info = par->targinfo;
	struct nf_loginfo li;

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

	if (info->bitmask & EBT_LOG_NFLOG)
		nf_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in,
		              par->out, &li, "%s", info->prefix);
	else
		ebt_log_packet(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	= XT_ALIGN(sizeof(struct ebt_log_info)),
	.me		= THIS_MODULE,
};

static struct nf_logger ebt_log_logger __read_mostly = {
	.name 		= "ebt_log",
	.logfn		= &ebt_log_packet,
	.me		= THIS_MODULE,
};

static int __init ebt_log_init(void)
{
	int ret;

	ret = xt_register_target(&ebt_log_tg_reg);
	if (ret < 0)
		return ret;
	nf_log_register(NFPROTO_BRIDGE, &ebt_log_logger);
	return 0;
}

static void __exit ebt_log_fini(void)
{
	nf_log_unregister(&ebt_log_logger);
	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
af5d6dc2	27	static bool 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)
19eda879	32	return false;
1da177e4	33	if (info->loglevel >= 8)
19eda879	34	return false;
1da177e4	35	info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
19eda879	36	return true;
1da177e4 LT	37	}
	38
	39	struct tcpudphdr
	40	{
47c183fa AV	41	__be16 src;
47c183fa AV	42	__be16 dst;
1da177e4 LT	43	};
	44
	45	struct arppayload
	46	{
	47	unsigned char mac_src[ETH_ALEN];
	48	unsigned char ip_src[4];
	49	unsigned char mac_dst[ETH_ALEN];
	50	unsigned char ip_dst[4];
	51	};
	52
abfdf1c4	53	static void print_MAC(const unsigned char *p)
1da177e4 LT	54	{
	55	int i;
	56
	57	for (i = 0; i < ETH_ALEN; i++, p++)
	58	printk("%02x%c", *p, i == ETH_ALEN - 1 ? ' ':':');
	59	}
	60
93f65158 KT	61	static void
	62	print_ports(const struct sk_buff *skb, uint8_t protocol, int offset)
	63	{
	64	if (protocol == IPPROTO_TCP \|\|
	65	protocol == IPPROTO_UDP \|\|
	66	protocol == IPPROTO_UDPLITE \|\|
	67	protocol == IPPROTO_SCTP \|\|
	68	protocol == IPPROTO_DCCP) {
	69	const struct tcpudphdr *pptr;
	70	struct tcpudphdr _ports;
	71
	72	pptr = skb_header_pointer(skb, offset,
	73	sizeof(_ports), &_ports);
	74	if (pptr == NULL) {
	75	printk(" INCOMPLETE TCP/UDP header");
	76	return;
	77	}
	78	printk(" SPT=%u DPT=%u", ntohs(pptr->src), ntohs(pptr->dst));
	79	}
	80	}
	81
d5228a4f	82	static void
76108cea	83	ebt_log_packet(u_int8_t pf, unsigned int hooknum,
d5228a4f BDS	84	const struct sk_buff skb, const struct net_device in,
	85	const struct net_device out, const struct nf_loginfo loginfo,
	86	const char *prefix)
1da177e4	87	{
d5228a4f	88	unsigned int bitmask;
1da177e4	89
1da177e4	90	spin_lock_bh(&ebt_log_lock);
d5228a4f BDS	91	printk("<%c>%s IN=%s OUT=%s MAC source = ", '0' + loginfo->u.log.level,
d5228a4f BDS	92	prefix, in ? in->name : "", out ? out->name : "");
1da177e4	93
1da177e4 LT	94	print_MAC(eth_hdr(skb)->h_source);
	95	printk("MAC dest = ");
	96	print_MAC(eth_hdr(skb)->h_dest);
	97
	98	printk("proto = 0x%04x", ntohs(eth_hdr(skb)->h_proto));
	99
d5228a4f BDS	100	if (loginfo->type == NF_LOG_TYPE_LOG)
	101	bitmask = loginfo->u.log.logflags;
	102	else
	103	bitmask = NF_LOG_MASK;
	104
	105	if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
1da177e4	106	htons(ETH_P_IP)){
abfdf1c4 JE	107	const struct iphdr *ih;
abfdf1c4 JE	108	struct iphdr _iph;
1da177e4 LT	109
	110	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	111	if (ih == NULL) {
	112	printk(" INCOMPLETE IP header");
	113	goto out;
	114	}
21454aaa HH	115	printk(" IP SRC=%pI4 IP DST=%pI4, IP tos=0x%02X, IP proto=%d",
21454aaa HH	116	&ih->saddr, &ih->daddr, ih->tos, ih->protocol);
93f65158 KT	117	print_ports(skb, ih->protocol, ih->ihl*4);
	118	goto out;
	119	}
	120
f586287e	121	#if defined(CONFIG_BRIDGE_EBT_IP6) \|\| defined(CONFIG_BRIDGE_EBT_IP6_MODULE)
93f65158 KT	122	if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto ==
	123	htons(ETH_P_IPV6)) {
	124	const struct ipv6hdr *ih;
	125	struct ipv6hdr _iph;
	126	uint8_t nexthdr;
	127	int offset_ph;
	128
	129	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	130	if (ih == NULL) {
	131	printk(" INCOMPLETE IPv6 header");
	132	goto out;
1da177e4	133	}
5b095d98	134	printk(" IPv6 SRC=%pI6 IPv6 DST=%pI6, IPv6 priority=0x%01X, Next Header=%d",
b189db5d	135	&ih->saddr, &ih->daddr, ih->priority, ih->nexthdr);
93f65158 KT	136	nexthdr = ih->nexthdr;
	137	offset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), &nexthdr);
	138	if (offset_ph == -1)
	139	goto out;
	140	print_ports(skb, nexthdr, offset_ph);
1da177e4 LT	141	goto out;
1da177e4 LT	142	}
f586287e	143	#endif
1da177e4	144
d5228a4f	145	if ((bitmask & EBT_LOG_ARP) &&
1da177e4 LT	146	((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) \|\|
1da177e4 LT	147	(eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
abfdf1c4 JE	148	const struct arphdr *ah;
abfdf1c4 JE	149	struct arphdr _arph;
1da177e4 LT	150
	151	ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
	152	if (ah == NULL) {
	153	printk(" INCOMPLETE ARP header");
	154	goto out;
	155	}
	156	printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
	157	ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
	158	ntohs(ah->ar_op));
	159
	160	/* If it's for Ethernet and the lengths are OK,
	161	* then log the ARP payload */
	162	if (ah->ar_hrd == htons(1) &&
	163	ah->ar_hln == ETH_ALEN &&
47c183fa	164	ah->ar_pln == sizeof(__be32)) {
abfdf1c4 JE	165	const struct arppayload *ap;
abfdf1c4 JE	166	struct arppayload _arpp;
1da177e4	167
85c1937b	168	ap = skb_header_pointer(skb, sizeof(_arph),
1da177e4 LT	169	sizeof(_arpp), &_arpp);
	170	if (ap == NULL) {
	171	printk(" INCOMPLETE ARP payload");
	172	goto out;
	173	}
	174	printk(" ARP MAC SRC=");
	175	print_MAC(ap->mac_src);
21454aaa	176	printk(" ARP IP SRC=%pI4", ap->ip_src);
1da177e4 LT	177	printk(" ARP MAC DST=");
1da177e4 LT	178	print_MAC(ap->mac_dst);
21454aaa	179	printk(" ARP IP DST=%pI4", ap->ip_dst);
1da177e4 LT	180	}
	181	}
	182	out:
	183	printk("\n");
	184	spin_unlock_bh(&ebt_log_lock);
d5228a4f BDS	185
	186	}
	187
2d06d4a5	188	static unsigned int
7eb35586	189	ebt_log_tg(struct sk_buff skb, const struct xt_target_param par)
d5228a4f	190	{
7eb35586	191	const struct ebt_log_info *info = par->targinfo;
d5228a4f BDS	192	struct nf_loginfo li;
	193
	194	li.type = NF_LOG_TYPE_LOG;
	195	li.u.log.level = info->loglevel;
	196	li.u.log.logflags = info->bitmask;
	197
bafac2a5	198	if (info->bitmask & EBT_LOG_NFLOG)
7eb35586 JE	199	nf_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in,
7eb35586 JE	200	par->out, &li, "%s", info->prefix);
bafac2a5	201	else
7eb35586 JE	202	ebt_log_packet(NFPROTO_BRIDGE, par->hooknum, skb, par->in,
7eb35586 JE	203	par->out, &li, info->prefix);
0ac6ab1f	204	return EBT_CONTINUE;
1da177e4 LT	205	}
1da177e4 LT	206
043ef46c JE	207	static struct xt_target ebt_log_tg_reg __read_mostly = {
043ef46c JE	208	.name = "log",
001a18d3 JE	209	.revision = 0,
001a18d3 JE	210	.family = NFPROTO_BRIDGE,
2d06d4a5 JE	211	.target = ebt_log_tg,
2d06d4a5 JE	212	.checkentry = ebt_log_tg_check,
18219d3f	213	.targetsize = XT_ALIGN(sizeof(struct ebt_log_info)),
1da177e4 LT	214	.me = THIS_MODULE,
	215	};
	216
704b3ea3	217	static struct nf_logger ebt_log_logger __read_mostly = {
d5228a4f BDS	218	.name = "ebt_log",
	219	.logfn = &ebt_log_packet,
	220	.me = THIS_MODULE,
	221	};
	222
65b4b4e8	223	static int __init ebt_log_init(void)
1da177e4	224	{
d5228a4f BDS	225	int ret;
d5228a4f BDS	226
043ef46c	227	ret = xt_register_target(&ebt_log_tg_reg);
d5228a4f BDS	228	if (ret < 0)
d5228a4f BDS	229	return ret;
ee999d8b	230	nf_log_register(NFPROTO_BRIDGE, &ebt_log_logger);
7e2acc7e	231	return 0;
1da177e4 LT	232	}
1da177e4 LT	233
65b4b4e8	234	static void __exit ebt_log_fini(void)
1da177e4	235	{
e92ad99c	236	nf_log_unregister(&ebt_log_logger);
043ef46c	237	xt_unregister_target(&ebt_log_tg_reg);
1da177e4 LT	238	}
1da177e4 LT	239
65b4b4e8 AM	240	module_init(ebt_log_init);
65b4b4e8 AM	241	module_exit(ebt_log_fini);
f776c4cd	242	MODULE_DESCRIPTION("Ebtables: Packet logging to syslog");
1da177e4	243	MODULE_LICENSE("GPL");