[mirror_ubuntu-artful-kernel.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 = dev_net(par->in ? par->in : par->out);

	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	}
	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
93f65158 KT	53	static void
	54	print_ports(const struct sk_buff *skb, uint8_t protocol, int offset)
	55	{
	56	if (protocol == IPPROTO_TCP \|\|
	57	protocol == IPPROTO_UDP \|\|
	58	protocol == IPPROTO_UDPLITE \|\|
	59	protocol == IPPROTO_SCTP \|\|
	60	protocol == IPPROTO_DCCP) {
	61	const struct tcpudphdr *pptr;
	62	struct tcpudphdr _ports;
	63
	64	pptr = skb_header_pointer(skb, offset,
	65	sizeof(_ports), &_ports);
	66	if (pptr == NULL) {
	67	printk(" INCOMPLETE TCP/UDP header");
	68	return;
	69	}
	70	printk(" SPT=%u DPT=%u", ntohs(pptr->src), ntohs(pptr->dst));
	71	}
	72	}
	73
d5228a4f	74	static void
8cdb46da HS	75	ebt_log_packet(struct net *net, u_int8_t pf, unsigned int hooknum,
	76	const struct sk_buff skb, const struct net_device in,
	77	const struct net_device out, const struct nf_loginfo loginfo,
	78	const char *prefix)
1da177e4	79	{
d5228a4f	80	unsigned int bitmask;
7d278924 G	81
	82	/* FIXME: Disabled from containers until syslog ns is supported */
	83	if (!net_eq(net, &init_net))
	84	return;
1da177e4	85
1da177e4	86	spin_lock_bh(&ebt_log_lock);
16af511a	87	printk(KERN_SOH "%c%s IN=%s OUT=%s MAC source = %pM MAC dest = %pM proto = 0x%04x",
be39ee11 TK	88	'0' + loginfo->u.log.level, prefix,
	89	in ? in->name : "", out ? out->name : "",
	90	eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
	91	ntohs(eth_hdr(skb)->h_proto));
1da177e4	92
d5228a4f BDS	93	if (loginfo->type == NF_LOG_TYPE_LOG)
	94	bitmask = loginfo->u.log.logflags;
	95	else
	96	bitmask = NF_LOG_MASK;
	97
	98	if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
31a5b837	99	htons(ETH_P_IP)) {
abfdf1c4 JE	100	const struct iphdr *ih;
abfdf1c4 JE	101	struct iphdr _iph;
1da177e4 LT	102
	103	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	104	if (ih == NULL) {
	105	printk(" INCOMPLETE IP header");
	106	goto out;
	107	}
21454aaa HH	108	printk(" IP SRC=%pI4 IP DST=%pI4, IP tos=0x%02X, IP proto=%d",
21454aaa HH	109	&ih->saddr, &ih->daddr, ih->tos, ih->protocol);
93f65158 KT	110	print_ports(skb, ih->protocol, ih->ihl*4);
	111	goto out;
	112	}
	113
e6373c4c	114	#if IS_ENABLED(CONFIG_BRIDGE_EBT_IP6)
93f65158 KT	115	if ((bitmask & EBT_LOG_IP6) && eth_hdr(skb)->h_proto ==
	116	htons(ETH_P_IPV6)) {
	117	const struct ipv6hdr *ih;
	118	struct ipv6hdr _iph;
	119	uint8_t nexthdr;
75f2811c	120	__be16 frag_off;
93f65158 KT	121	int offset_ph;
	122
	123	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	124	if (ih == NULL) {
	125	printk(" INCOMPLETE IPv6 header");
	126	goto out;
1da177e4	127	}
5b095d98	128	printk(" IPv6 SRC=%pI6 IPv6 DST=%pI6, IPv6 priority=0x%01X, Next Header=%d",
b189db5d	129	&ih->saddr, &ih->daddr, ih->priority, ih->nexthdr);
93f65158	130	nexthdr = ih->nexthdr;
75f2811c	131	offset_ph = ipv6_skip_exthdr(skb, sizeof(_iph), &nexthdr, &frag_off);
93f65158 KT	132	if (offset_ph == -1)
	133	goto out;
	134	print_ports(skb, nexthdr, offset_ph);
1da177e4 LT	135	goto out;
1da177e4 LT	136	}
f586287e	137	#endif
1da177e4	138
d5228a4f	139	if ((bitmask & EBT_LOG_ARP) &&
1da177e4 LT	140	((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) \|\|
1da177e4 LT	141	(eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
abfdf1c4 JE	142	const struct arphdr *ah;
abfdf1c4 JE	143	struct arphdr _arph;
1da177e4 LT	144
	145	ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
	146	if (ah == NULL) {
	147	printk(" INCOMPLETE ARP header");
	148	goto out;
	149	}
	150	printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
	151	ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
	152	ntohs(ah->ar_op));
	153
	154	/* If it's for Ethernet and the lengths are OK,
	155	* then log the ARP payload */
	156	if (ah->ar_hrd == htons(1) &&
	157	ah->ar_hln == ETH_ALEN &&
47c183fa	158	ah->ar_pln == sizeof(__be32)) {
abfdf1c4 JE	159	const struct arppayload *ap;
abfdf1c4 JE	160	struct arppayload _arpp;
1da177e4	161
85c1937b	162	ap = skb_header_pointer(skb, sizeof(_arph),
1da177e4 LT	163	sizeof(_arpp), &_arpp);
	164	if (ap == NULL) {
	165	printk(" INCOMPLETE ARP payload");
	166	goto out;
	167	}
be39ee11 TK	168	printk(" ARP MAC SRC=%pM ARP IP SRC=%pI4 ARP MAC DST=%pM ARP IP DST=%pI4",
be39ee11 TK	169	ap->mac_src, ap->ip_src, ap->mac_dst, ap->ip_dst);
1da177e4 LT	170	}
	171	}
	172	out:
	173	printk("\n");
	174	spin_unlock_bh(&ebt_log_lock);
d5228a4f BDS	175
	176	}
	177
2d06d4a5	178	static unsigned int
4b560b44	179	ebt_log_tg(struct sk_buff skb, const struct xt_action_param par)
d5228a4f	180	{
7eb35586	181	const struct ebt_log_info *info = par->targinfo;
d5228a4f	182	struct nf_loginfo li;
30e0c6a6	183	struct net *net = dev_net(par->in ? par->in : par->out);
d5228a4f BDS	184
	185	li.type = NF_LOG_TYPE_LOG;
	186	li.u.log.level = info->loglevel;
	187	li.u.log.logflags = info->bitmask;
	188
960649d1 PNA	189	/* Remember that we have to use ebt_log_packet() not to break backward
	190	* compatibility. We cannot use the default bridge packet logger via
	191	* nf_log_packet() with NFT_LOG_TYPE_LOG here. --Pablo
	192	*/
bafac2a5	193	if (info->bitmask & EBT_LOG_NFLOG)
30e0c6a6 G	194	nf_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb,
30e0c6a6 G	195	par->in, par->out, &li, "%s", info->prefix);
bafac2a5	196	else
8cdb46da	197	ebt_log_packet(net, NFPROTO_BRIDGE, par->hooknum, skb, par->in,
30e0c6a6	198	par->out, &li, info->prefix);
0ac6ab1f	199	return EBT_CONTINUE;
1da177e4 LT	200	}
1da177e4 LT	201
043ef46c JE	202	static struct xt_target ebt_log_tg_reg __read_mostly = {
043ef46c JE	203	.name = "log",
001a18d3 JE	204	.revision = 0,
001a18d3 JE	205	.family = NFPROTO_BRIDGE,
2d06d4a5 JE	206	.target = ebt_log_tg,
2d06d4a5 JE	207	.checkentry = ebt_log_tg_check,
fc0e3df4	208	.targetsize = sizeof(struct ebt_log_info),
1da177e4 LT	209	.me = THIS_MODULE,
	210	};
	211
65b4b4e8	212	static int __init ebt_log_init(void)
1da177e4	213	{
960649d1	214	return xt_register_target(&ebt_log_tg_reg);
1da177e4 LT	215	}
1da177e4 LT	216
65b4b4e8	217	static void __exit ebt_log_fini(void)
1da177e4	218	{
043ef46c	219	xt_unregister_target(&ebt_log_tg_reg);
1da177e4 LT	220	}
1da177e4 LT	221
65b4b4e8 AM	222	module_init(ebt_log_init);
65b4b4e8 AM	223	module_exit(ebt_log_fini);
f776c4cd	224	MODULE_DESCRIPTION("Ebtables: Packet logging to syslog");
1da177e4	225	MODULE_LICENSE("GPL");