[mirror_ubuntu-bionic-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/in.h>
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/netfilter_bridge/ebt_log.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/if_arp.h>
#include <linux/spinlock.h>

static DEFINE_SPINLOCK(ebt_log_lock);

static int ebt_log_check(const char *tablename, unsigned int hookmask,
   const struct ebt_entry *e, void *data, unsigned int datalen)
{
	struct ebt_log_info *info = (struct ebt_log_info *)data;

	if (datalen != EBT_ALIGN(sizeof(struct ebt_log_info)))
		return -EINVAL;
	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_MAC(unsigned char *p)
{
	int i;

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

#define myNIPQUAD(a) a[0], a[1], a[2], a[3]
static void
ebt_log_packet(unsigned int 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)){
		struct iphdr _iph, *ih;

		ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
		if (ih == NULL) {
			printk(" INCOMPLETE IP header");
			goto out;
		}
		printk(" IP SRC=%u.%u.%u.%u IP DST=%u.%u.%u.%u, IP "
		       "tos=0x%02X, IP proto=%d", NIPQUAD(ih->saddr),
		       NIPQUAD(ih->daddr), ih->tos, ih->protocol);
		if (ih->protocol == IPPROTO_TCP ||
		    ih->protocol == IPPROTO_UDP ||
		    ih->protocol == IPPROTO_SCTP ||
		    ih->protocol == IPPROTO_DCCP) {
			struct tcpudphdr _ports, *pptr;

			pptr = skb_header_pointer(skb, ih->ihl*4,
						  sizeof(_ports), &_ports);
			if (pptr == NULL) {
				printk(" INCOMPLETE TCP/UDP header");
				goto out;
			}
			printk(" SPT=%u DPT=%u", ntohs(pptr->src),
			   ntohs(pptr->dst));
		}
		goto out;
	}

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

		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)) {
			struct arppayload _arpp, *ap;

			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=%u.%u.%u.%u",
			       myNIPQUAD(ap->ip_src));
			printk(" ARP MAC DST=");
			print_MAC(ap->mac_dst);
			printk(" ARP IP DST=%u.%u.%u.%u",
			       myNIPQUAD(ap->ip_dst));
		}
	}
out:
	printk("\n");
	spin_unlock_bh(&ebt_log_lock);

}

static void ebt_log(const struct sk_buff *skb, unsigned int hooknr,
   const struct net_device *in, const struct net_device *out,
   const void *data, unsigned int datalen)
{
	struct ebt_log_info *info = (struct ebt_log_info *)data;
	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(PF_BRIDGE, hooknr, skb, in, out, &li,
		              "%s", info->prefix);
	else
		ebt_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li,
		               info->prefix);
}

static struct ebt_watcher log =
{
	.name		= EBT_LOG_WATCHER,
	.watcher	= ebt_log,
	.check		= ebt_log_check,
	.me		= THIS_MODULE,
};

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

static int __init ebt_log_init(void)
{
	int ret;

	ret = ebt_register_watcher(&log);
	if (ret < 0)
		return ret;
	if (nf_log_register(PF_BRIDGE, &ebt_log_logger) < 0) {
		printk(KERN_WARNING "ebt_log: not logging via system console "
		       "since somebody else already registered for PF_INET\n");
		/* we cannot make module load fail here, since otherwise 
		 * ebtables userspace would abort */
	}

	return 0;
}

static void __exit ebt_log_fini(void)
{
	nf_log_unregister_logger(&ebt_log_logger);
	ebt_unregister_watcher(&log);
}

module_init(ebt_log_init);
module_exit(ebt_log_fini);
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	*/
	11
14c85021	12	#include <linux/in.h>
1da177e4 LT	13	#include <linux/netfilter_bridge/ebtables.h>
1da177e4 LT	14	#include <linux/netfilter_bridge/ebt_log.h>
d5228a4f	15	#include <linux/netfilter.h>
1da177e4 LT	16	#include <linux/module.h>
1da177e4 LT	17	#include <linux/ip.h>
2e4e6a17	18	#include <linux/in.h>
1da177e4 LT	19	#include <linux/if_arp.h>
	20	#include <linux/spinlock.h>
	21
	22	static DEFINE_SPINLOCK(ebt_log_lock);
	23
	24	static int ebt_log_check(const char *tablename, unsigned int hookmask,
	25	const struct ebt_entry e, void data, unsigned int datalen)
	26	{
	27	struct ebt_log_info info = (struct ebt_log_info )data;
	28
	29	if (datalen != EBT_ALIGN(sizeof(struct ebt_log_info)))
	30	return -EINVAL;
	31	if (info->bitmask & ~EBT_LOG_MASK)
	32	return -EINVAL;
	33	if (info->loglevel >= 8)
	34	return -EINVAL;
	35	info->prefix[EBT_LOG_PREFIX_SIZE - 1] = '\0';
	36	return 0;
	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
	53	static void print_MAC(unsigned char *p)
	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
	61	#define myNIPQUAD(a) a[0], a[1], a[2], a[3]
d5228a4f BDS	62	static void
	63	ebt_log_packet(unsigned int pf, unsigned int hooknum,
	64	const struct sk_buff skb, const struct net_device in,
	65	const struct net_device out, const struct nf_loginfo loginfo,
	66	const char *prefix)
1da177e4	67	{
d5228a4f	68	unsigned int bitmask;
1da177e4	69
1da177e4	70	spin_lock_bh(&ebt_log_lock);
d5228a4f BDS	71	printk("<%c>%s IN=%s OUT=%s MAC source = ", '0' + loginfo->u.log.level,
d5228a4f BDS	72	prefix, in ? in->name : "", out ? out->name : "");
1da177e4	73
1da177e4 LT	74	print_MAC(eth_hdr(skb)->h_source);
	75	printk("MAC dest = ");
	76	print_MAC(eth_hdr(skb)->h_dest);
	77
	78	printk("proto = 0x%04x", ntohs(eth_hdr(skb)->h_proto));
	79
d5228a4f BDS	80	if (loginfo->type == NF_LOG_TYPE_LOG)
	81	bitmask = loginfo->u.log.logflags;
	82	else
	83	bitmask = NF_LOG_MASK;
	84
	85	if ((bitmask & EBT_LOG_IP) && eth_hdr(skb)->h_proto ==
1da177e4 LT	86	htons(ETH_P_IP)){
	87	struct iphdr _iph, *ih;
	88
	89	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
	90	if (ih == NULL) {
	91	printk(" INCOMPLETE IP header");
	92	goto out;
	93	}
d5228a4f BDS	94	printk(" IP SRC=%u.%u.%u.%u IP DST=%u.%u.%u.%u, IP "
	95	"tos=0x%02X, IP proto=%d", NIPQUAD(ih->saddr),
	96	NIPQUAD(ih->daddr), ih->tos, ih->protocol);
1da177e4	97	if (ih->protocol == IPPROTO_TCP \|\|
ab67a4d5 PM	98	ih->protocol == IPPROTO_UDP \|\|
	99	ih->protocol == IPPROTO_SCTP \|\|
	100	ih->protocol == IPPROTO_DCCP) {
1da177e4 LT	101	struct tcpudphdr _ports, *pptr;
	102
	103	pptr = skb_header_pointer(skb, ih->ihl*4,
	104	sizeof(_ports), &_ports);
	105	if (pptr == NULL) {
	106	printk(" INCOMPLETE TCP/UDP header");
	107	goto out;
	108	}
	109	printk(" SPT=%u DPT=%u", ntohs(pptr->src),
	110	ntohs(pptr->dst));
	111	}
	112	goto out;
	113	}
	114
d5228a4f	115	if ((bitmask & EBT_LOG_ARP) &&
1da177e4 LT	116	((eth_hdr(skb)->h_proto == htons(ETH_P_ARP)) \|\|
	117	(eth_hdr(skb)->h_proto == htons(ETH_P_RARP)))) {
	118	struct arphdr _arph, *ah;
	119
	120	ah = skb_header_pointer(skb, 0, sizeof(_arph), &_arph);
	121	if (ah == NULL) {
	122	printk(" INCOMPLETE ARP header");
	123	goto out;
	124	}
	125	printk(" ARP HTYPE=%d, PTYPE=0x%04x, OPCODE=%d",
	126	ntohs(ah->ar_hrd), ntohs(ah->ar_pro),
	127	ntohs(ah->ar_op));
	128
	129	/* If it's for Ethernet and the lengths are OK,
	130	* then log the ARP payload */
	131	if (ah->ar_hrd == htons(1) &&
	132	ah->ar_hln == ETH_ALEN &&
47c183fa	133	ah->ar_pln == sizeof(__be32)) {
1da177e4 LT	134	struct arppayload _arpp, *ap;
1da177e4 LT	135
85c1937b	136	ap = skb_header_pointer(skb, sizeof(_arph),
1da177e4 LT	137	sizeof(_arpp), &_arpp);
	138	if (ap == NULL) {
	139	printk(" INCOMPLETE ARP payload");
	140	goto out;
	141	}
	142	printk(" ARP MAC SRC=");
	143	print_MAC(ap->mac_src);
	144	printk(" ARP IP SRC=%u.%u.%u.%u",
	145	myNIPQUAD(ap->ip_src));
	146	printk(" ARP MAC DST=");
	147	print_MAC(ap->mac_dst);
	148	printk(" ARP IP DST=%u.%u.%u.%u",
	149	myNIPQUAD(ap->ip_dst));
	150	}
	151	}
	152	out:
	153	printk("\n");
	154	spin_unlock_bh(&ebt_log_lock);
d5228a4f BDS	155
	156	}
	157
	158	static void ebt_log(const struct sk_buff *skb, unsigned int hooknr,
	159	const struct net_device in, const struct net_device out,
	160	const void *data, unsigned int datalen)
	161	{
	162	struct ebt_log_info info = (struct ebt_log_info )data;
	163	struct nf_loginfo li;
	164
	165	li.type = NF_LOG_TYPE_LOG;
	166	li.u.log.level = info->loglevel;
	167	li.u.log.logflags = info->bitmask;
	168
bafac2a5 PM	169	if (info->bitmask & EBT_LOG_NFLOG)
bafac2a5 PM	170	nf_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li,
5c170a09	171	"%s", info->prefix);
bafac2a5 PM	172	else
	173	ebt_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li,
	174	info->prefix);
1da177e4 LT	175	}
	176
	177	static struct ebt_watcher log =
	178	{
	179	.name = EBT_LOG_WATCHER,
	180	.watcher = ebt_log,
	181	.check = ebt_log_check,
	182	.me = THIS_MODULE,
	183	};
	184
d5228a4f BDS	185	static struct nf_logger ebt_log_logger = {
	186	.name = "ebt_log",
	187	.logfn = &ebt_log_packet,
	188	.me = THIS_MODULE,
	189	};
	190
65b4b4e8	191	static int __init ebt_log_init(void)
1da177e4	192	{
d5228a4f BDS	193	int ret;
	194
	195	ret = ebt_register_watcher(&log);
	196	if (ret < 0)
	197	return ret;
	198	if (nf_log_register(PF_BRIDGE, &ebt_log_logger) < 0) {
	199	printk(KERN_WARNING "ebt_log: not logging via system console "
	200	"since somebody else already registered for PF_INET\n");
	201	/* we cannot make module load fail here, since otherwise
	202	* ebtables userspace would abort */
	203	}
	204
	205	return 0;
1da177e4 LT	206	}
1da177e4 LT	207
65b4b4e8	208	static void __exit ebt_log_fini(void)
1da177e4	209	{
d5228a4f	210	nf_log_unregister_logger(&ebt_log_logger);
1da177e4 LT	211	ebt_unregister_watcher(&log);
	212	}
	213
65b4b4e8 AM	214	module_init(ebt_log_init);
65b4b4e8 AM	215	module_exit(ebt_log_fini);
1da177e4	216	MODULE_LICENSE("GPL");