/* * This is a module which is used for logging packets. *//* (C) 2001 Jan Rekorajski <baggins@pld.org.pl> * (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/skbuff.h>#include <linux/ip.h>#include <linux/spinlock.h>#include <linux/icmpv6.h>#include <net/udp.h>#include <net/tcp.h>#include <net/ipv6.h>#include <linux/netfilter.h>#include <linux/netfilter_ipv6/ip6_tables.h>MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");MODULE_DESCRIPTION("IP6 tables LOG target module");MODULE_LICENSE("GPL");static unsigned int nflog = 1;MODULE_PARM(nflog, "i");MODULE_PARM_DESC(nflog, "register as internal netfilter logging module"); struct in_device;#include <net/route.h>#include <linux/netfilter_ipv6/ip6t_LOG.h>#if 0#define DEBUGP printk#else#define DEBUGP(format, args...)#endifstruct esphdr {	__u32   spi;}; /* FIXME evil kludge */        /* Use lock to serialize, so printks don't overlap */static spinlock_t log_lock = SPIN_LOCK_UNLOCKED;/* takes in current header and pointer to the header *//* if another header exists, sets hdrptr to the next header   and returns the new header value, else returns IPPROTO_NONE */static u_int8_t ip6_nexthdr(u_int8_t currenthdr, u_int8_t **hdrptr){	u_int8_t hdrlen, nexthdr = IPPROTO_NONE;	switch(currenthdr){		case IPPROTO_AH:		/* whoever decided to do the length of AUTH for ipv6		in 32bit units unlike other headers should be beaten...		repeatedly...with a large stick...no, an even LARGER		stick...no, you're still not thinking big enough */			nexthdr = **hdrptr;			hdrlen = *hdrptr[1] * 4 + 8;			*hdrptr = *hdrptr + hdrlen;			break;		/*stupid rfc2402 */		case IPPROTO_DSTOPTS:		case IPPROTO_ROUTING:		case IPPROTO_HOPOPTS:			nexthdr = **hdrptr;			hdrlen = *hdrptr[1] * 8 + 8;			*hdrptr = *hdrptr + hdrlen;			break;		case IPPROTO_FRAGMENT:			nexthdr = **hdrptr;			*hdrptr = *hdrptr + 8;			break;	}		return nexthdr;}/* One level of recursion won't kill us */static void dump_packet(const struct ip6t_log_info *info,			struct ipv6hdr *ipv6h, int recurse){	u_int8_t currenthdr = ipv6h->nexthdr;	u_int8_t *hdrptr;	int fragment;	/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000" */	printk("SRC=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(ipv6h->saddr));	printk("DST=%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x ", NIP6(ipv6h->daddr));	/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */	printk("LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",	       ntohs(ipv6h->payload_len) + sizeof(struct ipv6hdr),	       (ntohl(*(u_int32_t *)ipv6h) & 0x0ff00000) >> 20,	       ipv6h->hop_limit,	       (ntohl(*(u_int32_t *)ipv6h) & 0x000fffff));	fragment = 0;	hdrptr = (u_int8_t *)(ipv6h + 1);	while (currenthdr != IPPROTO_NONE) {		if ((currenthdr == IPPROTO_TCP) ||		    (currenthdr == IPPROTO_UDP) ||		    (currenthdr == IPPROTO_ICMPV6))			break;		/* Max length: 48 "OPT (...) " */		printk("OPT ( ");		switch (currenthdr) {		case IPPROTO_FRAGMENT: {			struct frag_hdr *fhdr = (struct frag_hdr *)hdrptr;			/* Max length: 11 "FRAG:65535 " */			printk("FRAG:%u ", ntohs(fhdr->frag_off) & 0xFFF8);			/* Max length: 11 "INCOMPLETE " */			if (fhdr->frag_off & htons(0x0001))				printk("INCOMPLETE ");			printk("ID:%08x ", fhdr->identification);			if (ntohs(fhdr->frag_off) & 0xFFF8)				fragment = 1;			break;		}		case IPPROTO_DSTOPTS:		case IPPROTO_ROUTING:		case IPPROTO_HOPOPTS:			break;		/* Max Length */		case IPPROTO_AH:		case IPPROTO_ESP:			if (info->logflags & IP6T_LOG_IPOPT) {				struct esphdr *esph = (struct esphdr *)hdrptr;				int esp = (currenthdr == IPPROTO_ESP);				/* Max length: 4 "ESP " */				printk("%s ",esp ? "ESP" : "AH");				/* Length: 15 "SPI=0xF1234567 " */				printk("SPI=0x%x ", ntohl(esph->spi) );				break;			}		default:			break;		}		printk(") ");		currenthdr = ip6_nexthdr(currenthdr, &hdrptr);	}	switch (currenthdr) {	case IPPROTO_TCP: {		struct tcphdr *tcph = (struct tcphdr *)hdrptr;		/* Max length: 10 "PROTO=TCP " */		printk("PROTO=TCP ");		if (fragment)			break;		/* Max length: 20 "SPT=65535 DPT=65535 " */		printk("SPT=%u DPT=%u ",		       ntohs(tcph->source), ntohs(tcph->dest));		/* Max length: 30 "SEQ=4294967295 ACK=4294967295 " */		if (info->logflags & IP6T_LOG_TCPSEQ)			printk("SEQ=%u ACK=%u ",			       ntohl(tcph->seq), ntohl(tcph->ack_seq));		/* Max length: 13 "WINDOW=65535 " */		printk("WINDOW=%u ", ntohs(tcph->window));		/* Max length: 9 "RES=0x3F " */		printk("RES=0x%02x ", (u_int8_t)(ntohl(tcp_flag_word(tcph) & TCP_RESERVED_BITS) >> 22));		/* Max length: 32 "CWR ECE URG ACK PSH RST SYN FIN " */		if (tcph->cwr)			printk("CWR ");		if (tcph->ece)			printk("ECE ");		if (tcph->urg)			printk("URG ");		if (tcph->ack)			printk("ACK ");		if (tcph->psh)			printk("PSH ");		if (tcph->rst)			printk("RST ");		if (tcph->syn)			printk("SYN ");		if (tcph->fin)			printk("FIN ");		/* Max length: 11 "URGP=65535 " */		printk("URGP=%u ", ntohs(tcph->urg_ptr));		if ((info->logflags & IP6T_LOG_TCPOPT)		    && tcph->doff * 4 != sizeof(struct tcphdr)) {			unsigned int i;			/* Max length: 127 "OPT (" 15*4*2chars ") " */			printk("OPT (");			for (i =sizeof(struct tcphdr); i < tcph->doff * 4; i++)				printk("%02X", ((u_int8_t *)tcph)[i]);			printk(") ");		}		break;	}	case IPPROTO_UDP: {		struct udphdr *udph = (struct udphdr *)hdrptr;		/* Max length: 10 "PROTO=UDP " */		printk("PROTO=UDP ");		if (fragment)			break;		/* Max length: 20 "SPT=65535 DPT=65535 " */		printk("SPT=%u DPT=%u LEN=%u ",		       ntohs(udph->source), ntohs(udph->dest),		       ntohs(udph->len));		break;	}	case IPPROTO_ICMPV6: {		struct icmp6hdr *icmp6h = (struct icmp6hdr *)hdrptr;		/* Max length: 13 "PROTO=ICMPv6 " */		printk("PROTO=ICMPv6 ");		if (fragment)			break;		/* Max length: 18 "TYPE=255 CODE=255 " */		printk("TYPE=%u CODE=%u ", icmp6h->icmp6_type, icmp6h->icmp6_code);		switch (icmp6h->icmp6_type) {		case ICMPV6_ECHO_REQUEST:		case ICMPV6_ECHO_REPLY:			/* Max length: 19 "ID=65535 SEQ=65535 " */			printk("ID=%u SEQ=%u ",				ntohs(icmp6h->icmp6_identifier),				ntohs(icmp6h->icmp6_sequence));			break;		case ICMPV6_MGM_QUERY:		case ICMPV6_MGM_REPORT:		case ICMPV6_MGM_REDUCTION:			break;		case ICMPV6_PARAMPROB:			/* Max length: 17 "POINTER=ffffffff " */			printk("POINTER=%08x ", ntohl(icmp6h->icmp6_pointer));			/* Fall through */		case ICMPV6_DEST_UNREACH:		case ICMPV6_PKT_TOOBIG:		case ICMPV6_TIME_EXCEED:			/* Max length: 3+maxlen */			if (recurse) {				printk("[");				dump_packet(info, (struct ipv6hdr *)(icmp6h + 1), 0);				printk("] ");			}			/* Max length: 10 "MTU=65535 " */			if (icmp6h->icmp6_type == ICMPV6_PKT_TOOBIG)				printk("MTU=%u ", ntohl(icmp6h->icmp6_mtu));		}		break;	}	/* Max length: 10 "PROTO=255 " */	default:		printk("PROTO=%u ", currenthdr);	}}static voidip6t_log_packet(unsigned int hooknum,		const struct sk_buff *skb,		const struct net_device *in,		const struct net_device *out,		const struct ip6t_log_info *loginfo,		const char *level_string,		const char *prefix){	struct ipv6hdr *ipv6h = skb->nh.ipv6h;	spin_lock_bh(&log_lock);	printk(level_string);	printk("%sIN=%s OUT=%s ",		prefix == NULL ? loginfo->prefix : prefix,		in ? in->name : "",		out ? out->name : "");	if (in && !out) {		/* MAC logging for input chain only. */		printk("MAC=");		if (skb->dev && skb->dev->hard_header_len && skb->mac.raw != (void*)ipv6h) {			if (skb->dev->type != ARPHRD_SIT){			  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 {			  int i;			  unsigned char *p = skb->mac.raw;			  if ( p - (ETH_ALEN*2+2) > skb->head ){			    p -= (ETH_ALEN+2);			    for (i = 0; i < (ETH_ALEN); i++,p++)				printk("%02x%s", *p,					i == ETH_ALEN-1 ? "->" : ":");			    p -= (ETH_ALEN*2);			    for (i = 0; i < (ETH_ALEN); i++,p++)				printk("%02x%c", *p,					i == ETH_ALEN-1 ? ' ' : ':');			  }			  			  if ((skb->dev->addr_len == 4) &&			      skb->dev->hard_header_len > 20){			    printk("TUNNEL=");			    p = skb->mac.raw + 12;			    for (i = 0; i < 4; i++,p++)				printk("%3d%s", *p,					i == 3 ? "->" : ".");			    for (i = 0; i < 4; i++,p++)				printk("%3d%c", *p,					i == 3 ? ' ' : '.');			  }			}		} else			printk(" ");	}	dump_packet(loginfo, ipv6h, 1);	printk("\n");	spin_unlock_bh(&log_lock);}static unsigned intip6t_log_target(struct sk_buff **pskb,		unsigned int hooknum,		const struct net_device *in,		const struct net_device *out,		const void *targinfo,		void *userinfo){	const struct ip6t_log_info *loginfo = targinfo;	char level_string[4] = "< >";	level_string[1] = '0' + (loginfo->level % 8);	ip6t_log_packet(hooknum, *pskb, in, out, loginfo, level_string, NULL);	return IP6T_CONTINUE;}static voidip6t_logfn(unsigned int hooknum,	   const struct sk_buff *skb,	   const struct net_device *in,	   const struct net_device *out,	   const char *prefix){	struct ip6t_log_info loginfo = {		.level = 0,		.logflags = IP6T_LOG_MASK,		.prefix = ""	};	ip6t_log_packet(hooknum, skb, in, out, &loginfo, KERN_WARNING, prefix);}static int ip6t_log_checkentry(const char *tablename,			       const struct ip6t_entry *e,			       void *targinfo,			       unsigned int targinfosize,			       unsigned int hook_mask){	const struct ip6t_log_info *loginfo = targinfo;	if (targinfosize != IP6T_ALIGN(sizeof(struct ip6t_log_info))) {		DEBUGP("LOG: targinfosize %u != %u\n",		       targinfosize, IP6T_ALIGN(sizeof(struct ip6t_log_info)));		return 0;	}	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 ip6t_target ip6t_log_reg = {	.name 		= "LOG",	.target 	= ip6t_log_target, 	.checkentry	= ip6t_log_checkentry, 	.me 		= THIS_MODULE,};static int __init init(void){	if (ip6t_register_target(&ip6t_log_reg))		return -EINVAL;	if (nflog)		nf_log_register(PF_INET6, &ip6t_logfn);	return 0;}static void __exit fini(void){	if (nflog)		nf_log_unregister(PF_INET6, &ip6t_logfn);	ip6t_unregister_target(&ip6t_log_reg);}module_init(init);module_exit(fini);