[net-next-2.6.git] / net / ipv4 / netfilter / ipt_LOG.c

/*
 * This is a module which is used for logging packets.
 */

/* (C) 1999-2001 Paul `Rusty' Russell
 * (C) 2002-2004 Netfilter Core Team <coreteam@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.
 */

#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/tcp.h>
#include <net/route.h>

#include <linux/netfilter.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_LOG.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
MODULE_DESCRIPTION("iptables syslog logging module");

#if 0
#define DEBUGP printk
#else
#define DEBUGP(format, args...)
#endif

/* Use lock to serialize, so printks don't overlap */
static DEFINE_SPINLOCK(log_lock);

/* One level of recursion won't kill us */
static void dump_packet(const struct nf_loginfo *info,
			const struct sk_buff *skb,
			unsigned int iphoff)
{
	struct iphdr _iph, *ih;
	unsigned int logflags;

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

	ih = skb_header_pointer(skb, iphoff, sizeof(_iph), &_iph);
	if (ih == NULL) {
		printk("TRUNCATED");
		return;
	}

	/* Important fields:
	 * TOS, len, DF/MF, fragment offset, TTL, src, dst, options. */
	/* Max length: 40 "SRC=255.255.255.255 DST=255.255.255.255 " */
	printk("SRC=%u.%u.%u.%u DST=%u.%u.%u.%u ",
	       NIPQUAD(ih->saddr), NIPQUAD(ih->daddr));

	/* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */
	printk("LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
	       ntohs(ih->tot_len), ih->tos & IPTOS_TOS_MASK,
	       ih->tos & IPTOS_PREC_MASK, ih->ttl, ntohs(ih->id));

	/* Max length: 6 "CE DF MF " */
	if (ntohs(ih->frag_off) & IP_CE)
		printk("CE ");
	if (ntohs(ih->frag_off) & IP_DF)
		printk("DF ");
	if (ntohs(ih->frag_off) & IP_MF)
		printk("MF ");

	/* Max length: 11 "FRAG:65535 " */
	if (ntohs(ih->frag_off) & IP_OFFSET)
		printk("FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);

	if ((logflags & IPT_LOG_IPOPT)
	    && ih->ihl * 4 > sizeof(struct iphdr)) {
		unsigned char _opt[4 * 15 - sizeof(struct iphdr)], *op;
		unsigned int i, optsize;

		optsize = ih->ihl * 4 - sizeof(struct iphdr);
		op = skb_header_pointer(skb, iphoff+sizeof(_iph),
					optsize, _opt);
		if (op == NULL) {
			printk("TRUNCATED");
			return;
		}

		/* Max length: 127 "OPT (" 15*4*2chars ") " */
		printk("OPT (");
		for (i = 0; i < optsize; i++)
			printk("%02X", op[i]);
		printk(") ");
	}

	switch (ih->protocol) {
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;

		/* Max length: 10 "PROTO=TCP " */
		printk("PROTO=TCP ");

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		th = skb_header_pointer(skb, iphoff + ih->ihl * 4,
					sizeof(_tcph), &_tcph);
		if (th == NULL) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		/* Max length: 20 "SPT=65535 DPT=65535 " */
		printk("SPT=%u DPT=%u ",
		       ntohs(th->source), ntohs(th->dest));
		/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
		if (logflags & IPT_LOG_TCPSEQ)
			printk("SEQ=%u ACK=%u ",
			       ntohl(th->seq), ntohl(th->ack_seq));
		/* Max length: 13 "WINDOW=65535 " */
		printk("WINDOW=%u ", ntohs(th->window));
		/* Max length: 9 "RES=0x3F " */
		printk("RES=0x%02x ", (u8)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
		/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
		if (th->cwr)
			printk("CWR ");
		if (th->ece)
			printk("ECE ");
		if (th->urg)
			printk("URG ");
		if (th->ack)
			printk("ACK ");
		if (th->psh)
			printk("PSH ");
		if (th->rst)
			printk("RST ");
		if (th->syn)
			printk("SYN ");
		if (th->fin)
			printk("FIN ");
		/* Max length: 11 "URGP=65535 " */
		printk("URGP=%u ", ntohs(th->urg_ptr));

		if ((logflags & IPT_LOG_TCPOPT)
		    && th->doff * 4 > sizeof(struct tcphdr)) {
			unsigned char _opt[4 * 15 - sizeof(struct tcphdr)];
			unsigned char *op;
			unsigned int i, optsize;

			optsize = th->doff * 4 - sizeof(struct tcphdr);
			op = skb_header_pointer(skb,
						iphoff+ih->ihl*4+sizeof(_tcph),
						optsize, _opt);
			if (op == NULL) {
				printk("TRUNCATED");
				return;
			}

			/* Max length: 127 "OPT (" 15*4*2chars ") " */
			printk("OPT (");
			for (i = 0; i < optsize; i++)
				printk("%02X", op[i]);
			printk(") ");
		}
		break;
	}
	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		/* Max length: 10 "PROTO=UDP " */
		printk("PROTO=UDP ");

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		uh = skb_header_pointer(skb, iphoff+ih->ihl*4,
					sizeof(_udph), &_udph);
		if (uh == NULL) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		/* Max length: 20 "SPT=65535 DPT=65535 " */
		printk("SPT=%u DPT=%u LEN=%u ",
		       ntohs(uh->source), ntohs(uh->dest),
		       ntohs(uh->len));
		break;
	}
	case IPPROTO_ICMP: {
		struct icmphdr _icmph, *ich;
		static const size_t required_len[NR_ICMP_TYPES+1]
			= { [ICMP_ECHOREPLY] = 4,
			    [ICMP_DEST_UNREACH]
			    = 8 + sizeof(struct iphdr),
			    [ICMP_SOURCE_QUENCH]
			    = 8 + sizeof(struct iphdr),
			    [ICMP_REDIRECT]
			    = 8 + sizeof(struct iphdr),
			    [ICMP_ECHO] = 4,
			    [ICMP_TIME_EXCEEDED]
			    = 8 + sizeof(struct iphdr),
			    [ICMP_PARAMETERPROB]
			    = 8 + sizeof(struct iphdr),
			    [ICMP_TIMESTAMP] = 20,
			    [ICMP_TIMESTAMPREPLY] = 20,
			    [ICMP_ADDRESS] = 12,
			    [ICMP_ADDRESSREPLY] = 12 };

		/* Max length: 11 "PROTO=ICMP " */
		printk("PROTO=ICMP ");

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		ich = skb_header_pointer(skb, iphoff + ih->ihl * 4,
					 sizeof(_icmph), &_icmph);
		if (ich == NULL) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		/* Max length: 18 "TYPE=255 CODE=255 " */
		printk("TYPE=%u CODE=%u ", ich->type, ich->code);

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		if (ich->type <= NR_ICMP_TYPES
		    && required_len[ich->type]
		    && skb->len-iphoff-ih->ihl*4 < required_len[ich->type]) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		switch (ich->type) {
		case ICMP_ECHOREPLY:
		case ICMP_ECHO:
			/* Max length: 19 "ID=65535 SEQ=65535 " */
			printk("ID=%u SEQ=%u ",
			       ntohs(ich->un.echo.id),
			       ntohs(ich->un.echo.sequence));
			break;

		case ICMP_PARAMETERPROB:
			/* Max length: 14 "PARAMETER=255 " */
			printk("PARAMETER=%u ",
			       ntohl(ich->un.gateway) >> 24);
			break;
		case ICMP_REDIRECT:
			/* Max length: 24 "GATEWAY=255.255.255.255 " */
			printk("GATEWAY=%u.%u.%u.%u ",
			       NIPQUAD(ich->un.gateway));
			/* Fall through */
		case ICMP_DEST_UNREACH:
		case ICMP_SOURCE_QUENCH:
		case ICMP_TIME_EXCEEDED:
			/* Max length: 3+maxlen */
			if (!iphoff) { /* Only recurse once. */
				printk("[");
				dump_packet(info, skb,
					    iphoff + ih->ihl*4+sizeof(_icmph));
				printk("] ");
			}

			/* Max length: 10 "MTU=65535 " */
			if (ich->type == ICMP_DEST_UNREACH
			    && ich->code == ICMP_FRAG_NEEDED)
				printk("MTU=%u ", ntohs(ich->un.frag.mtu));
		}
		break;
	}
	/* Max Length */
	case IPPROTO_AH: {
		struct ip_auth_hdr _ahdr, *ah;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
		
		/* Max length: 9 "PROTO=AH " */
		printk("PROTO=AH ");

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		ah = skb_header_pointer(skb, iphoff+ih->ihl*4,
					sizeof(_ahdr), &_ahdr);
		if (ah == NULL) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		/* Length: 15 "SPI=0xF1234567 " */
		printk("SPI=0x%x ", ntohl(ah->spi));
		break;
	}
	case IPPROTO_ESP: {
		struct ip_esp_hdr _esph, *eh;

		/* Max length: 10 "PROTO=ESP " */
		printk("PROTO=ESP ");

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
		eh = skb_header_pointer(skb, iphoff+ih->ihl*4,
					sizeof(_esph), &_esph);
		if (eh == NULL) {
			printk("INCOMPLETE [%u bytes] ",
			       skb->len - iphoff - ih->ihl*4);
			break;
		}

		/* Length: 15 "SPI=0xF1234567 " */
		printk("SPI=0x%x ", ntohl(eh->spi));
		break;
	}
	/* Max length: 10 "PROTO 255 " */
	default:
		printk("PROTO=%u ", ih->protocol);
	}

	/* Max length: 15 "UID=4294967295 " */
 	if ((logflags & IPT_LOG_UID) && !iphoff && skb->sk) {
		read_lock_bh(&skb->sk->sk_callback_lock);
		if (skb->sk->sk_socket && skb->sk->sk_socket->file)
 			printk("UID=%u ", skb->sk->sk_socket->file->f_uid);
		read_unlock_bh(&skb->sk->sk_callback_lock);
	}

	/* Proto    Max log string length */
	/* IP:      40+46+6+11+127 = 230 */
	/* TCP:     10+max(25,20+30+13+9+32+11+127) = 252 */
	/* UDP:     10+max(25,20) = 35 */
	/* ICMP:    11+max(25, 18+25+max(19,14,24+3+n+10,3+n+10)) = 91+n */
	/* ESP:     10+max(25)+15 = 50 */
	/* AH:      9+max(25)+15 = 49 */
	/* unknown: 10 */

	/* (ICMP allows recursion one level deep) */
	/* maxlen =  IP + ICMP +  IP + max(TCP,UDP,ICMP,unknown) */
	/* maxlen = 230+   91  + 230 + 252 = 803 */
}

static struct nf_loginfo default_loginfo = {
	.type	= NF_LOG_TYPE_LOG,
	.u = {
		.log = {
			.level    = 0,
			.logflags = NF_LOG_MASK,
		},
	},
};

static void
ipt_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)
{
	if (!loginfo)
		loginfo = &default_loginfo;

	spin_lock_bh(&log_lock);
	printk("<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
	       prefix,
	       in ? in->name : "",
	       out ? out->name : "");
#ifdef CONFIG_BRIDGE_NETFILTER
	if (skb->nf_bridge) {
		struct net_device *physindev = skb->nf_bridge->physindev;
		struct net_device *physoutdev = skb->nf_bridge->physoutdev;

		if (physindev && in != physindev)
			printk("PHYSIN=%s ", physindev->name);
		if (physoutdev && out != physoutdev)
			printk("PHYSOUT=%s ", physoutdev->name);
	}
#endif

	if (in && !out) {
		/* MAC logging for input chain only. */
		printk("MAC=");
		if (skb->dev && skb->dev->hard_header_len
		    && skb->mac.raw != (void*)skb->nh.iph) {
			int i;
			unsigned char *p = skb->mac.raw;
			for (i = 0; i < skb->dev->hard_header_len; i++,p++)
				printk("%02x%c", *p,
				       i==skb->dev->hard_header_len - 1
				       ? ' ':':');
		} else
			printk(" ");
	}

	dump_packet(loginfo, skb, 0);
	printk("\n");
	spin_unlock_bh(&log_lock);
}

static unsigned int
ipt_log_target(struct sk_buff **pskb,
	       const struct net_device *in,
	       const struct net_device *out,
	       unsigned int hooknum,
	       const struct xt_target *target,
	       const void *targinfo)
{
	const struct ipt_log_info *loginfo = targinfo;
	struct nf_loginfo li;

	li.type = NF_LOG_TYPE_LOG;
	li.u.log.level = loginfo->level;
	li.u.log.logflags = loginfo->logflags;

	if (loginfo->logflags & IPT_LOG_NFLOG)
		nf_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
		              "%s", loginfo->prefix);
	else
		ipt_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
		               loginfo->prefix);

	return IPT_CONTINUE;
}

static int ipt_log_checkentry(const char *tablename,
			      const void *e,
			      const struct xt_target *target,
			      void *targinfo,
			      unsigned int hook_mask)
{
	const struct ipt_log_info *loginfo = targinfo;

	if (loginfo->level >= 8) {
		DEBUGP("LOG: level %u >= 8\n", loginfo->level);
		return 0;
	}
	if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') {
		DEBUGP("LOG: prefix term %i\n",
		       loginfo->prefix[sizeof(loginfo->prefix)-1]);
		return 0;
	}
	return 1;
}

static struct ipt_target ipt_log_reg = {
	.name		= "LOG",
	.target		= ipt_log_target,
	.targetsize	= sizeof(struct ipt_log_info),
	.checkentry	= ipt_log_checkentry,
	.me		= THIS_MODULE,
};

static struct nf_logger ipt_log_logger ={
	.name		= "ipt_LOG",
	.logfn		= &ipt_log_packet,
	.me		= THIS_MODULE,
};

static int __init ipt_log_init(void)
{
	if (ipt_register_target(&ipt_log_reg))
		return -EINVAL;
	if (nf_log_register(PF_INET, &ipt_log_logger) < 0) {
		printk(KERN_WARNING "ipt_LOG: not logging via system console "
		       "since somebody else already registered for PF_INET\n");
		/* we cannot make module load fail here, since otherwise
		 * iptables userspace would abort */
	}
	
	return 0;
}

static void __exit ipt_log_fini(void)
{
	nf_log_unregister_logger(&ipt_log_logger);
	ipt_unregister_target(&ipt_log_reg);
}

module_init(ipt_log_init);
module_exit(ipt_log_fini);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This is a module which is used for logging packets.
	3	*/
	4
	5	/* (C) 1999-2001 Paul `Rusty' Russell
	6	* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/spinlock.h>
	15	#include <linux/skbuff.h>
	16	#include <linux/ip.h>
	17	#include <net/icmp.h>
	18	#include <net/udp.h>
	19	#include <net/tcp.h>
	20	#include <net/route.h>
	21
	22	#include <linux/netfilter.h>
	23	#include <linux/netfilter_ipv4/ip_tables.h>
	24	#include <linux/netfilter_ipv4/ipt_LOG.h>
	25
	26	MODULE_LICENSE("GPL");
	27	MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
	28	MODULE_DESCRIPTION("iptables syslog logging module");
	29
1da177e4 LT	30	#if 0
	31	#define DEBUGP printk
	32	#else
	33	#define DEBUGP(format, args...)
	34	#endif
	35
	36	/* Use lock to serialize, so printks don't overlap */
	37	static DEFINE_SPINLOCK(log_lock);
	38
	39	/* One level of recursion won't kill us */
608c8e4f	40	static void dump_packet(const struct nf_loginfo *info,
1da177e4 LT	41	const struct sk_buff *skb,
	42	unsigned int iphoff)
	43	{
	44	struct iphdr _iph, *ih;
608c8e4f HW	45	unsigned int logflags;
	46
	47	if (info->type == NF_LOG_TYPE_LOG)
	48	logflags = info->u.log.logflags;
	49	else
	50	logflags = NF_LOG_MASK;
1da177e4 LT	51
	52	ih = skb_header_pointer(skb, iphoff, sizeof(_iph), &_iph);
	53	if (ih == NULL) {
	54	printk("TRUNCATED");
	55	return;
	56	}
	57
	58	/* Important fields:
	59	* TOS, len, DF/MF, fragment offset, TTL, src, dst, options. */
	60	/* Max length: 40 "SRC=255.255.255.255 DST=255.255.255.255 " */
	61	printk("SRC=%u.%u.%u.%u DST=%u.%u.%u.%u ",
	62	NIPQUAD(ih->saddr), NIPQUAD(ih->daddr));
	63
	64	/* Max length: 46 "LEN=65535 TOS=0xFF PREC=0xFF TTL=255 ID=65535 " */
	65	printk("LEN=%u TOS=0x%02X PREC=0x%02X TTL=%u ID=%u ",
	66	ntohs(ih->tot_len), ih->tos & IPTOS_TOS_MASK,
	67	ih->tos & IPTOS_PREC_MASK, ih->ttl, ntohs(ih->id));
	68
	69	/* Max length: 6 "CE DF MF " */
	70	if (ntohs(ih->frag_off) & IP_CE)
	71	printk("CE ");
	72	if (ntohs(ih->frag_off) & IP_DF)
	73	printk("DF ");
	74	if (ntohs(ih->frag_off) & IP_MF)
	75	printk("MF ");
	76
	77	/* Max length: 11 "FRAG:65535 " */
	78	if (ntohs(ih->frag_off) & IP_OFFSET)
	79	printk("FRAG:%u ", ntohs(ih->frag_off) & IP_OFFSET);
	80
608c8e4f	81	if ((logflags & IPT_LOG_IPOPT)
1da177e4 LT	82	&& ih->ihl * 4 > sizeof(struct iphdr)) {
	83	unsigned char _opt[4 * 15 - sizeof(struct iphdr)], *op;
	84	unsigned int i, optsize;
	85
	86	optsize = ih->ihl * 4 - sizeof(struct iphdr);
	87	op = skb_header_pointer(skb, iphoff+sizeof(_iph),
	88	optsize, _opt);
	89	if (op == NULL) {
	90	printk("TRUNCATED");
	91	return;
	92	}
	93
	94	/* Max length: 127 "OPT (" 1542chars ") " */
	95	printk("OPT (");
	96	for (i = 0; i < optsize; i++)
	97	printk("%02X", op[i]);
	98	printk(") ");
	99	}
	100
	101	switch (ih->protocol) {
	102	case IPPROTO_TCP: {
	103	struct tcphdr _tcph, *th;
	104
	105	/* Max length: 10 "PROTO=TCP " */
	106	printk("PROTO=TCP ");
	107
	108	if (ntohs(ih->frag_off) & IP_OFFSET)
	109	break;
	110
	111	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
	112	th = skb_header_pointer(skb, iphoff + ih->ihl * 4,
	113	sizeof(_tcph), &_tcph);
	114	if (th == NULL) {
	115	printk("INCOMPLETE [%u bytes] ",
	116	skb->len - iphoff - ih->ihl*4);
	117	break;
	118	}
	119
	120	/* Max length: 20 "SPT=65535 DPT=65535 " */
	121	printk("SPT=%u DPT=%u ",
	122	ntohs(th->source), ntohs(th->dest));
	123	/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */
608c8e4f	124	if (logflags & IPT_LOG_TCPSEQ)
1da177e4 LT	125	printk("SEQ=%u ACK=%u ",
	126	ntohl(th->seq), ntohl(th->ack_seq));
	127	/* Max length: 13 "WINDOW=65535 " */
	128	printk("WINDOW=%u ", ntohs(th->window));
	129	/* Max length: 9 "RES=0x3F " */
	130	printk("RES=0x%02x ", (u8)(ntohl(tcp_flag_word(th) & TCP_RESERVED_BITS) >> 22));
	131	/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */
	132	if (th->cwr)
	133	printk("CWR ");
	134	if (th->ece)
	135	printk("ECE ");
	136	if (th->urg)
	137	printk("URG ");
	138	if (th->ack)
	139	printk("ACK ");
	140	if (th->psh)
	141	printk("PSH ");
	142	if (th->rst)
	143	printk("RST ");
	144	if (th->syn)
	145	printk("SYN ");
	146	if (th->fin)
	147	printk("FIN ");
	148	/* Max length: 11 "URGP=65535 " */
	149	printk("URGP=%u ", ntohs(th->urg_ptr));
	150
608c8e4f	151	if ((logflags & IPT_LOG_TCPOPT)
1da177e4 LT	152	&& th->doff * 4 > sizeof(struct tcphdr)) {
	153	unsigned char _opt[4 * 15 - sizeof(struct tcphdr)];
	154	unsigned char *op;
	155	unsigned int i, optsize;
	156
	157	optsize = th->doff * 4 - sizeof(struct tcphdr);
	158	op = skb_header_pointer(skb,
	159	iphoff+ih->ihl*4+sizeof(_tcph),
	160	optsize, _opt);
	161	if (op == NULL) {
	162	printk("TRUNCATED");
	163	return;
	164	}
	165
	166	/* Max length: 127 "OPT (" 1542chars ") " */
	167	printk("OPT (");
	168	for (i = 0; i < optsize; i++)
	169	printk("%02X", op[i]);
	170	printk(") ");
	171	}
	172	break;
	173	}
	174	case IPPROTO_UDP: {
	175	struct udphdr _udph, *uh;
	176
	177	/* Max length: 10 "PROTO=UDP " */
	178	printk("PROTO=UDP ");
	179
	180	if (ntohs(ih->frag_off) & IP_OFFSET)
	181	break;
	182
	183	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
	184	uh = skb_header_pointer(skb, iphoff+ih->ihl*4,
	185	sizeof(_udph), &_udph);
	186	if (uh == NULL) {
	187	printk("INCOMPLETE [%u bytes] ",
	188	skb->len - iphoff - ih->ihl*4);
	189	break;
	190	}
	191
	192	/* Max length: 20 "SPT=65535 DPT=65535 " */
	193	printk("SPT=%u DPT=%u LEN=%u ",
	194	ntohs(uh->source), ntohs(uh->dest),
	195	ntohs(uh->len));
	196	break;
	197	}
	198	case IPPROTO_ICMP: {
	199	struct icmphdr _icmph, *ich;
9b5b5cff	200	static const size_t required_len[NR_ICMP_TYPES+1]
1da177e4 LT	201	= { [ICMP_ECHOREPLY] = 4,
	202	[ICMP_DEST_UNREACH]
	203	= 8 + sizeof(struct iphdr),
	204	[ICMP_SOURCE_QUENCH]
	205	= 8 + sizeof(struct iphdr),
	206	[ICMP_REDIRECT]
	207	= 8 + sizeof(struct iphdr),
	208	[ICMP_ECHO] = 4,
	209	[ICMP_TIME_EXCEEDED]
	210	= 8 + sizeof(struct iphdr),
	211	[ICMP_PARAMETERPROB]
	212	= 8 + sizeof(struct iphdr),
	213	[ICMP_TIMESTAMP] = 20,
	214	[ICMP_TIMESTAMPREPLY] = 20,
	215	[ICMP_ADDRESS] = 12,
	216	[ICMP_ADDRESSREPLY] = 12 };
	217
	218	/* Max length: 11 "PROTO=ICMP " */
	219	printk("PROTO=ICMP ");
	220
	221	if (ntohs(ih->frag_off) & IP_OFFSET)
	222	break;
	223
	224	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
	225	ich = skb_header_pointer(skb, iphoff + ih->ihl * 4,
	226	sizeof(_icmph), &_icmph);
	227	if (ich == NULL) {
	228	printk("INCOMPLETE [%u bytes] ",
	229	skb->len - iphoff - ih->ihl*4);
	230	break;
	231	}
	232
	233	/* Max length: 18 "TYPE=255 CODE=255 " */
	234	printk("TYPE=%u CODE=%u ", ich->type, ich->code);
	235
	236	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
	237	if (ich->type <= NR_ICMP_TYPES
	238	&& required_len[ich->type]
	239	&& skb->len-iphoff-ih->ihl*4 < required_len[ich->type]) {
	240	printk("INCOMPLETE [%u bytes] ",
	241	skb->len - iphoff - ih->ihl*4);
	242	break;
	243	}
	244
	245	switch (ich->type) {
	246	case ICMP_ECHOREPLY:
	247	case ICMP_ECHO:
	248	/* Max length: 19 "ID=65535 SEQ=65535 " */
	249	printk("ID=%u SEQ=%u ",
	250	ntohs(ich->un.echo.id),
	251	ntohs(ich->un.echo.sequence));
	252	break;
	253
	254	case ICMP_PARAMETERPROB:
	255	/* Max length: 14 "PARAMETER=255 " */
	256	printk("PARAMETER=%u ",
	257	ntohl(ich->un.gateway) >> 24);
	258	break;
	259	case ICMP_REDIRECT:
	260	/* Max length: 24 "GATEWAY=255.255.255.255 " */
	261	printk("GATEWAY=%u.%u.%u.%u ",
	262	NIPQUAD(ich->un.gateway));
	263	/* Fall through */
	264	case ICMP_DEST_UNREACH:
265	case ICMP_SOURCE_QUENCH:
266	case ICMP_TIME_EXCEEDED:
267	/* Max length: 3+maxlen */
268	if (!iphoff) { /* Only recurse once. */
269	printk("[");
270	dump_packet(info, skb,
271	iphoff + ih->ihl*4+sizeof(_icmph));
272	printk("] ");
273	}
274
275	/* Max length: 10 "MTU=65535 " */
276	if (ich->type == ICMP_DEST_UNREACH
277	&& ich->code == ICMP_FRAG_NEEDED)
278	printk("MTU=%u ", ntohs(ich->un.frag.mtu));
279	}
280	break;
281	}
282	/* Max Length */
283	case IPPROTO_AH: {
284	struct ip_auth_hdr _ahdr, *ah;
285
286	if (ntohs(ih->frag_off) & IP_OFFSET)
287	break;
288
289	/* Max length: 9 "PROTO=AH " */
290	printk("PROTO=AH ");
291
292	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
293	ah = skb_header_pointer(skb, iphoff+ih->ihl*4,
294	sizeof(_ahdr), &_ahdr);
295	if (ah == NULL) {
296	printk("INCOMPLETE [%u bytes] ",
297	skb->len - iphoff - ih->ihl*4);
298	break;
299	}
300
301	/* Length: 15 "SPI=0xF1234567 " */
302	printk("SPI=0x%x ", ntohl(ah->spi));
303	break;
304	}
305	case IPPROTO_ESP: {
306	struct ip_esp_hdr _esph, *eh;
307
308	/* Max length: 10 "PROTO=ESP " */
309	printk("PROTO=ESP ");
310
311	if (ntohs(ih->frag_off) & IP_OFFSET)
312	break;
313
314	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
315	eh = skb_header_pointer(skb, iphoff+ih->ihl*4,
316	sizeof(_esph), &_esph);
317	if (eh == NULL) {
318	printk("INCOMPLETE [%u bytes] ",
319	skb->len - iphoff - ih->ihl*4);
320	break;
321	}
322
323	/* Length: 15 "SPI=0xF1234567 " */
324	printk("SPI=0x%x ", ntohl(eh->spi));
325	break;
326	}
327	/* Max length: 10 "PROTO 255 " */
328	default:
329	printk("PROTO=%u ", ih->protocol);
330	}
331
332	/* Max length: 15 "UID=4294967295 " */
608c8e4f	333	if ((logflags & IPT_LOG_UID) && !iphoff && skb->sk) {
1da177e4 LT	334	read_lock_bh(&skb->sk->sk_callback_lock);
	335	if (skb->sk->sk_socket && skb->sk->sk_socket->file)
	336	printk("UID=%u ", skb->sk->sk_socket->file->f_uid);
	337	read_unlock_bh(&skb->sk->sk_callback_lock);
	338	}
	339
	340	/* Proto Max log string length */
	341	/* IP: 40+46+6+11+127 = 230 */
	342	/* TCP: 10+max(25,20+30+13+9+32+11+127) = 252 */
	343	/* UDP: 10+max(25,20) = 35 */
	344	/* ICMP: 11+max(25, 18+25+max(19,14,24+3+n+10,3+n+10)) = 91+n */
	345	/* ESP: 10+max(25)+15 = 50 */
	346	/* AH: 9+max(25)+15 = 49 */
	347	/* unknown: 10 */
	348
	349	/* (ICMP allows recursion one level deep) */
	350	/* maxlen = IP + ICMP + IP + max(TCP,UDP,ICMP,unknown) */
	351	/* maxlen = 230+ 91 + 230 + 252 = 803 */
	352	}
	353
d127e94a	354	static struct nf_loginfo default_loginfo = {
608c8e4f HW	355	.type = NF_LOG_TYPE_LOG,
	356	.u = {
	357	.log = {
	358	.level = 0,
	359	.logflags = NF_LOG_MASK,
	360	},
	361	},
	362	};
	363
1da177e4	364	static void
608c8e4f HW	365	ipt_log_packet(unsigned int pf,
608c8e4f HW	366	unsigned int hooknum,
1da177e4 LT	367	const struct sk_buff *skb,
	368	const struct net_device *in,
	369	const struct net_device *out,
608c8e4f	370	const struct nf_loginfo *loginfo,
1da177e4 LT	371	const char *prefix)
1da177e4 LT	372	{
608c8e4f HW	373	if (!loginfo)
	374	loginfo = &default_loginfo;
	375
1da177e4	376	spin_lock_bh(&log_lock);
608c8e4f HW	377	printk("<%d>%sIN=%s OUT=%s ", loginfo->u.log.level,
608c8e4f HW	378	prefix,
1da177e4 LT	379	in ? in->name : "",
	380	out ? out->name : "");
	381	#ifdef CONFIG_BRIDGE_NETFILTER
	382	if (skb->nf_bridge) {
	383	struct net_device *physindev = skb->nf_bridge->physindev;
	384	struct net_device *physoutdev = skb->nf_bridge->physoutdev;
	385
	386	if (physindev && in != physindev)
	387	printk("PHYSIN=%s ", physindev->name);
	388	if (physoutdev && out != physoutdev)
	389	printk("PHYSOUT=%s ", physoutdev->name);
	390	}
	391	#endif
	392
	393	if (in && !out) {
	394	/* MAC logging for input chain only. */
	395	printk("MAC=");
	396	if (skb->dev && skb->dev->hard_header_len
	397	&& skb->mac.raw != (void*)skb->nh.iph) {
	398	int i;
	399	unsigned char *p = skb->mac.raw;
	400	for (i = 0; i < skb->dev->hard_header_len; i++,p++)
	401	printk("%02x%c", *p,
	402	i==skb->dev->hard_header_len - 1
	403	? ' ':':');
	404	} else
	405	printk(" ");
	406	}
	407
	408	dump_packet(loginfo, skb, 0);
	409	printk("\n");
	410	spin_unlock_bh(&log_lock);
	411	}
	412
	413	static unsigned int
	414	ipt_log_target(struct sk_buff **pskb,
	415	const struct net_device *in,
	416	const struct net_device *out,
	417	unsigned int hooknum,
c4986734	418	const struct xt_target *target,
fe1cb108	419	const void *targinfo)
1da177e4 LT	420	{
1da177e4 LT	421	const struct ipt_log_info *loginfo = targinfo;
608c8e4f	422	struct nf_loginfo li;
1da177e4	423
608c8e4f HW	424	li.type = NF_LOG_TYPE_LOG;
	425	li.u.log.level = loginfo->level;
	426	li.u.log.logflags = loginfo->logflags;
1da177e4	427
bafac2a5 PM	428	if (loginfo->logflags & IPT_LOG_NFLOG)
bafac2a5 PM	429	nf_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
5c170a09	430	"%s", loginfo->prefix);
bafac2a5 PM	431	else
	432	ipt_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
	433	loginfo->prefix);
1da177e4	434
608c8e4f	435	return IPT_CONTINUE;
1da177e4 LT	436	}
	437
	438	static int ipt_log_checkentry(const char *tablename,
2e4e6a17	439	const void *e,
c4986734	440	const struct xt_target *target,
1da177e4	441	void *targinfo,
1da177e4 LT	442	unsigned int hook_mask)
	443	{
	444	const struct ipt_log_info *loginfo = targinfo;
	445
1da177e4 LT	446	if (loginfo->level >= 8) {
	447	DEBUGP("LOG: level %u >= 8\n", loginfo->level);
	448	return 0;
	449	}
1da177e4 LT	450	if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') {
	451	DEBUGP("LOG: prefix term %i\n",
	452	loginfo->prefix[sizeof(loginfo->prefix)-1]);
	453	return 0;
	454	}
1da177e4 LT	455	return 1;
	456	}
	457
	458	static struct ipt_target ipt_log_reg = {
	459	.name = "LOG",
	460	.target = ipt_log_target,
1d5cd909	461	.targetsize = sizeof(struct ipt_log_info),
1da177e4 LT	462	.checkentry = ipt_log_checkentry,
	463	.me = THIS_MODULE,
	464	};
	465
608c8e4f HW	466	static struct nf_logger ipt_log_logger ={
	467	.name = "ipt_LOG",
	468	.logfn = &ipt_log_packet,
	469	.me = THIS_MODULE,
	470	};
	471
65b4b4e8	472	static int __init ipt_log_init(void)
1da177e4 LT	473	{
	474	if (ipt_register_target(&ipt_log_reg))
	475	return -EINVAL;
608c8e4f HW	476	if (nf_log_register(PF_INET, &ipt_log_logger) < 0) {
	477	printk(KERN_WARNING "ipt_LOG: not logging via system console "
	478	"since somebody else already registered for PF_INET\n");
	479	/* we cannot make module load fail here, since otherwise
	480	* iptables userspace would abort */
	481	}
1da177e4 LT	482
	483	return 0;
	484	}
	485
65b4b4e8	486	static void __exit ipt_log_fini(void)
1da177e4	487	{
608c8e4f	488	nf_log_unregister_logger(&ipt_log_logger);
1da177e4 LT	489	ipt_unregister_target(&ipt_log_reg);
	490	}
	491
65b4b4e8 AM	492	module_init(ipt_log_init);
65b4b4e8 AM	493	module_exit(ipt_log_fini);