net/ipv6/netfilter/nf_log_ipv6.c - kernel/bruno - Git at Google

 /* (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.
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/skbuff.h>
 #include <linux/if_arp.h>
 #include <linux/ip.h>
 #include <net/ipv6.h>
 #include <net/icmp.h>
 #include <net/udp.h>
 #include <net/tcp.h>
 #include <net/route.h>

 #include <linux/netfilter.h>
 #include <linux/netfilter_ipv6/ip6_tables.h>
 #include <linux/netfilter/xt_LOG.h>
 #include <net/netfilter/nf_log.h>

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

 /* One level of recursion won't kill us */
 static void dump_ipv6_packet(struct nf_log_buf *m,
 			     const struct nf_loginfo *info,
 			     const struct sk_buff *skb, unsigned int ip6hoff,
 			     int recurse)
 {
 	u_int8_t currenthdr;
 	int fragment;
 	struct ipv6hdr _ip6h;
 	const struct ipv6hdr *ih;
 	unsigned int ptr;
 	unsigned int hdrlen = 0;
 	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, ip6hoff, sizeof(_ip6h), &_ip6h);
 	if (ih == NULL) {
 		nf_log_buf_add(m, "TRUNCATED");
 		return;
 	}

 	/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
 	nf_log_buf_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);

 	/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
 	nf_log_buf_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
 	       ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
 	       (ntohl(*(__be32 *)ih) & 0x0ff00000) >> 20,
 	       ih->hop_limit,
 	       (ntohl(*(__be32 *)ih) & 0x000fffff));

 	fragment = 0;
 	ptr = ip6hoff + sizeof(struct ipv6hdr);
 	currenthdr = ih->nexthdr;
 	while (currenthdr != NEXTHDR_NONE && ip6t_ext_hdr(currenthdr)) {
 		struct ipv6_opt_hdr _hdr;
 		const struct ipv6_opt_hdr *hp;

 		hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
 		if (hp == NULL) {
 			nf_log_buf_add(m, "TRUNCATED");
 			return;
 		}

 		/* Max length: 48 "OPT (...) " */
 		if (logflags & XT_LOG_IPOPT)
 			nf_log_buf_add(m, "OPT ( ");

 		switch (currenthdr) {
 		case IPPROTO_FRAGMENT: {
 			struct frag_hdr _fhdr;
 			const struct frag_hdr *fh;

 			nf_log_buf_add(m, "FRAG:");
 			fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
 						&_fhdr);
 			if (fh == NULL) {
 				nf_log_buf_add(m, "TRUNCATED ");
 				return;
 			}

 			/* Max length: 6 "65535 " */
 			nf_log_buf_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);

 			/* Max length: 11 "INCOMPLETE " */
 			if (fh->frag_off & htons(0x0001))
 				nf_log_buf_add(m, "INCOMPLETE ");

 			nf_log_buf_add(m, "ID:%08x ",
 				       ntohl(fh->identification));

 			if (ntohs(fh->frag_off) & 0xFFF8)
 				fragment = 1;

 			hdrlen = 8;

 			break;
 		}
 		case IPPROTO_DSTOPTS:
 		case IPPROTO_ROUTING:
 		case IPPROTO_HOPOPTS:
 			if (fragment) {
 				if (logflags & XT_LOG_IPOPT)
 					nf_log_buf_add(m, ")");
 				return;
 			}
 			hdrlen = ipv6_optlen(hp);
 			break;
 		/* Max Length */
 		case IPPROTO_AH:
 			if (logflags & XT_LOG_IPOPT) {
 				struct ip_auth_hdr _ahdr;
 				const struct ip_auth_hdr *ah;

 				/* Max length: 3 "AH " */
 				nf_log_buf_add(m, "AH ");

 				if (fragment) {
 					nf_log_buf_add(m, ")");
 					return;
 				}

 				ah = skb_header_pointer(skb, ptr, sizeof(_ahdr),
 							&_ahdr);
 				if (ah == NULL) {
 					/*
 					 * Max length: 26 "INCOMPLETE [65535
 					 *  bytes] )"
 					 */
 					nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
 						       skb->len - ptr);
 					return;
 				}

 				/* Length: 15 "SPI=0xF1234567 */
 				nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));

 			}

 			hdrlen = (hp->hdrlen+2)<<2;
 			break;
 		case IPPROTO_ESP:
 			if (logflags & XT_LOG_IPOPT) {
 				struct ip_esp_hdr _esph;
 				const struct ip_esp_hdr *eh;

 				/* Max length: 4 "ESP " */
 				nf_log_buf_add(m, "ESP ");

 				if (fragment) {
 					nf_log_buf_add(m, ")");
 					return;
 				}

 				/*
 				 * Max length: 26 "INCOMPLETE [65535 bytes] )"
 				 */
 				eh = skb_header_pointer(skb, ptr, sizeof(_esph),
 							&_esph);
 				if (eh == NULL) {
 					nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
 						       skb->len - ptr);
 					return;
 				}

 				/* Length: 16 "SPI=0xF1234567 )" */
 				nf_log_buf_add(m, "SPI=0x%x )",
 					       ntohl(eh->spi));
 			}
 			return;
 		default:
 			/* Max length: 20 "Unknown Ext Hdr 255" */
 			nf_log_buf_add(m, "Unknown Ext Hdr %u", currenthdr);
 			return;
 		}
 		if (logflags & XT_LOG_IPOPT)
 			nf_log_buf_add(m, ") ");

 		currenthdr = hp->nexthdr;
 		ptr += hdrlen;
 	}

 	switch (currenthdr) {
 	case IPPROTO_TCP:
 		if (nf_log_dump_tcp_header(m, skb, currenthdr, fragment,
 					   ptr, logflags))
 			return;
 		break;
 	case IPPROTO_UDP:
 	case IPPROTO_UDPLITE:
 		if (nf_log_dump_udp_header(m, skb, currenthdr, fragment, ptr))
 			return;
 		break;
 	case IPPROTO_ICMPV6: {
 		struct icmp6hdr _icmp6h;
 		const struct icmp6hdr *ic;

 		/* Max length: 13 "PROTO=ICMPv6 " */
 		nf_log_buf_add(m, "PROTO=ICMPv6 ");

 		if (fragment)
 			break;

 		/* Max length: 25 "INCOMPLETE [65535 bytes] " */
 		ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
 		if (ic == NULL) {
 			nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
 				       skb->len - ptr);
 			return;
 		}

 		/* Max length: 18 "TYPE=255 CODE=255 " */
 		nf_log_buf_add(m, "TYPE=%u CODE=%u ",
 			       ic->icmp6_type, ic->icmp6_code);

 		switch (ic->icmp6_type) {
 		case ICMPV6_ECHO_REQUEST:
 		case ICMPV6_ECHO_REPLY:
 			/* Max length: 19 "ID=65535 SEQ=65535 " */
 			nf_log_buf_add(m, "ID=%u SEQ=%u ",
 				ntohs(ic->icmp6_identifier),
 				ntohs(ic->icmp6_sequence));
 			break;
 		case ICMPV6_MGM_QUERY:
 		case ICMPV6_MGM_REPORT:
 		case ICMPV6_MGM_REDUCTION:
 			break;

 		case ICMPV6_PARAMPROB:
 			/* Max length: 17 "POINTER=ffffffff " */
 			nf_log_buf_add(m, "POINTER=%08x ",
 				       ntohl(ic->icmp6_pointer));
 			/* Fall through */
 		case ICMPV6_DEST_UNREACH:
 		case ICMPV6_PKT_TOOBIG:
 		case ICMPV6_TIME_EXCEED:
 			/* Max length: 3+maxlen */
 			if (recurse) {
 				nf_log_buf_add(m, "[");
 				dump_ipv6_packet(m, info, skb,
 						 ptr + sizeof(_icmp6h), 0);
 				nf_log_buf_add(m, "] ");
 			}

 			/* Max length: 10 "MTU=65535 " */
 			if (ic->icmp6_type == ICMPV6_PKT_TOOBIG) {
 				nf_log_buf_add(m, "MTU=%u ",
 					       ntohl(ic->icmp6_mtu));
 			}
 		}
 		break;
 	}
 	/* Max length: 10 "PROTO=255 " */
 	default:
 		nf_log_buf_add(m, "PROTO=%u ", currenthdr);
 	}

 	/* Max length: 15 "UID=4294967295 " */
 	if ((logflags & XT_LOG_UID) && recurse)
 		nf_log_dump_sk_uid_gid(m, skb->sk);

 	/* Max length: 16 "MARK=0xFFFFFFFF " */
 	if (recurse && skb->mark)
 		nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
 }

 static void dump_ipv6_mac_header(struct nf_log_buf *m,
 				 const struct nf_loginfo *info,
 				 const struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 	unsigned int logflags = 0;

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

 	if (!(logflags & XT_LOG_MACDECODE))
 		goto fallback;

 	switch (dev->type) {
 	case ARPHRD_ETHER:
 		nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
 		       eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
 		       ntohs(eth_hdr(skb)->h_proto));
 		return;
 	default:
 		break;
 	}

 fallback:
 	nf_log_buf_add(m, "MAC=");
 	if (dev->hard_header_len &&
 	    skb->mac_header != skb->network_header) {
 		const unsigned char *p = skb_mac_header(skb);
 		unsigned int len = dev->hard_header_len;
 		unsigned int i;

 		if (dev->type == ARPHRD_SIT) {
 			p -= ETH_HLEN;

 			if (p < skb->head)
 				p = NULL;
 		}

 		if (p != NULL) {
 			nf_log_buf_add(m, "%02x", *p++);
 			for (i = 1; i < len; i++)
 				nf_log_buf_add(m, ":%02x", *p++);
 		}
 		nf_log_buf_add(m, " ");

 		if (dev->type == ARPHRD_SIT) {
 			const struct iphdr *iph =
 				(struct iphdr *)skb_mac_header(skb);
 			nf_log_buf_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr,
 				       &iph->daddr);
 		}
 	} else {
 		nf_log_buf_add(m, " ");
 	}
 }

 static void nf_log_ip6_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)
 {
 	struct nf_log_buf *m;

 	/* FIXME: Disabled from containers until syslog ns is supported */
 	if (!net_eq(net, &init_net))
 		return;

 	m = nf_log_buf_open();

 	if (!loginfo)
 		loginfo = &default_loginfo;

 	nf_log_dump_packet_common(m, pf, hooknum, skb, in, out,
 				  loginfo, prefix);

 	if (in != NULL)
 		dump_ipv6_mac_header(m, loginfo, skb);

 	dump_ipv6_packet(m, loginfo, skb, skb_network_offset(skb), 1);

 	nf_log_buf_close(m);
 }

 static struct nf_logger nf_ip6_logger __read_mostly = {
 	.name		= "nf_log_ipv6",
 	.type		= NF_LOG_TYPE_LOG,
 	.logfn		= nf_log_ip6_packet,
 	.me		= THIS_MODULE,
 };

 static int __net_init nf_log_ipv6_net_init(struct net *net)
 {
 	nf_log_set(net, NFPROTO_IPV6, &nf_ip6_logger);
 	return 0;
 }

 static void __net_exit nf_log_ipv6_net_exit(struct net *net)
 {
 	nf_log_unset(net, &nf_ip6_logger);
 }

 static struct pernet_operations nf_log_ipv6_net_ops = {
 	.init = nf_log_ipv6_net_init,
 	.exit = nf_log_ipv6_net_exit,
 };

 static int __init nf_log_ipv6_init(void)
 {
 	int ret;

 	ret = register_pernet_subsys(&nf_log_ipv6_net_ops);
 	if (ret < 0)
 		return ret;

 	ret = nf_log_register(NFPROTO_IPV6, &nf_ip6_logger);
 	if (ret < 0) {
 		pr_err("failed to register logger\n");
 		goto err1;
 	}

 	return 0;

 err1:
 	unregister_pernet_subsys(&nf_log_ipv6_net_ops);
 	return ret;
 }

 static void __exit nf_log_ipv6_exit(void)
 {
 	unregister_pernet_subsys(&nf_log_ipv6_net_ops);
 	nf_log_unregister(&nf_ip6_logger);
 }

 module_init(nf_log_ipv6_init);
 module_exit(nf_log_ipv6_exit);

 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
 MODULE_DESCRIPTION("Netfilter IPv6 packet logging");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_NF_LOGGER(AF_INET6, 0);
	/* (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.
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/spinlock.h>
	#include <linux/skbuff.h>
	#include <linux/if_arp.h>
	#include <linux/ip.h>
	#include <net/ipv6.h>
	#include <net/icmp.h>
	#include <net/udp.h>
	#include <net/tcp.h>
	#include <net/route.h>

	#include <linux/netfilter.h>
	#include <linux/netfilter_ipv6/ip6_tables.h>
	#include <linux/netfilter/xt_LOG.h>
	#include <net/netfilter/nf_log.h>

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

	/* One level of recursion won't kill us */
	static void dump_ipv6_packet(struct nf_log_buf *m,
	const struct nf_loginfo *info,
	const struct sk_buff *skb, unsigned int ip6hoff,
	int recurse)
	{
	u_int8_t currenthdr;
	int fragment;
	struct ipv6hdr _ip6h;
	const struct ipv6hdr *ih;
	unsigned int ptr;
	unsigned int hdrlen = 0;
	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, ip6hoff, sizeof(_ip6h), &_ip6h);
	if (ih == NULL) {
	nf_log_buf_add(m, "TRUNCATED");
	return;
	}

	/* Max length: 88 "SRC=0000.0000.0000.0000.0000.0000.0000.0000 DST=0000.0000.0000.0000.0000.0000.0000.0000 " */
	nf_log_buf_add(m, "SRC=%pI6 DST=%pI6 ", &ih->saddr, &ih->daddr);

	/* Max length: 44 "LEN=65535 TC=255 HOPLIMIT=255 FLOWLBL=FFFFF " */
	nf_log_buf_add(m, "LEN=%Zu TC=%u HOPLIMIT=%u FLOWLBL=%u ",
	ntohs(ih->payload_len) + sizeof(struct ipv6hdr),
	(ntohl((__be32 )ih) & 0x0ff00000) >> 20,
	ih->hop_limit,
	(ntohl((__be32 )ih) & 0x000fffff));

	fragment = 0;
	ptr = ip6hoff + sizeof(struct ipv6hdr);
	currenthdr = ih->nexthdr;
	while (currenthdr != NEXTHDR_NONE && ip6t_ext_hdr(currenthdr)) {
	struct ipv6_opt_hdr _hdr;
	const struct ipv6_opt_hdr *hp;

	hp = skb_header_pointer(skb, ptr, sizeof(_hdr), &_hdr);
	if (hp == NULL) {
	nf_log_buf_add(m, "TRUNCATED");
	return;
	}

	/* Max length: 48 "OPT (...) " */
	if (logflags & XT_LOG_IPOPT)
	nf_log_buf_add(m, "OPT ( ");

	switch (currenthdr) {
	case IPPROTO_FRAGMENT: {
	struct frag_hdr _fhdr;
	const struct frag_hdr *fh;

	nf_log_buf_add(m, "FRAG:");
	fh = skb_header_pointer(skb, ptr, sizeof(_fhdr),
	&_fhdr);
	if (fh == NULL) {
	nf_log_buf_add(m, "TRUNCATED ");
	return;
	}

	/* Max length: 6 "65535 " */
	nf_log_buf_add(m, "%u ", ntohs(fh->frag_off) & 0xFFF8);

	/* Max length: 11 "INCOMPLETE " */
	if (fh->frag_off & htons(0x0001))
	nf_log_buf_add(m, "INCOMPLETE ");

	nf_log_buf_add(m, "ID:%08x ",
	ntohl(fh->identification));

	if (ntohs(fh->frag_off) & 0xFFF8)
	fragment = 1;

	hdrlen = 8;

	break;
	}
	case IPPROTO_DSTOPTS:
	case IPPROTO_ROUTING:
	case IPPROTO_HOPOPTS:
	if (fragment) {
	if (logflags & XT_LOG_IPOPT)
	nf_log_buf_add(m, ")");
	return;
	}
	hdrlen = ipv6_optlen(hp);
	break;
	/* Max Length */
	case IPPROTO_AH:
	if (logflags & XT_LOG_IPOPT) {
	struct ip_auth_hdr _ahdr;
	const struct ip_auth_hdr *ah;

	/* Max length: 3 "AH " */
	nf_log_buf_add(m, "AH ");

	if (fragment) {
	nf_log_buf_add(m, ")");
	return;
	}

	ah = skb_header_pointer(skb, ptr, sizeof(_ahdr),
	&_ahdr);
	if (ah == NULL) {
	/*
	* Max length: 26 "INCOMPLETE [65535
	* bytes] )"
	*/
	nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
	skb->len - ptr);
	return;
	}

	/* Length: 15 "SPI=0xF1234567 */
	nf_log_buf_add(m, "SPI=0x%x ", ntohl(ah->spi));

	}

	hdrlen = (hp->hdrlen+2)<<2;
	break;
	case IPPROTO_ESP:
	if (logflags & XT_LOG_IPOPT) {
	struct ip_esp_hdr _esph;
	const struct ip_esp_hdr *eh;

	/* Max length: 4 "ESP " */
	nf_log_buf_add(m, "ESP ");

	if (fragment) {
	nf_log_buf_add(m, ")");
	return;
	}

	/*
	* Max length: 26 "INCOMPLETE [65535 bytes] )"
	*/
	eh = skb_header_pointer(skb, ptr, sizeof(_esph),
	&_esph);
	if (eh == NULL) {
	nf_log_buf_add(m, "INCOMPLETE [%u bytes] )",
	skb->len - ptr);
	return;
	}

	/* Length: 16 "SPI=0xF1234567 )" */
	nf_log_buf_add(m, "SPI=0x%x )",
	ntohl(eh->spi));
	}
	return;
	default:
	/* Max length: 20 "Unknown Ext Hdr 255" */
	nf_log_buf_add(m, "Unknown Ext Hdr %u", currenthdr);
	return;
	}
	if (logflags & XT_LOG_IPOPT)
	nf_log_buf_add(m, ") ");

	currenthdr = hp->nexthdr;
	ptr += hdrlen;
	}

	switch (currenthdr) {
	case IPPROTO_TCP:
	if (nf_log_dump_tcp_header(m, skb, currenthdr, fragment,
	ptr, logflags))
	return;
	break;
	case IPPROTO_UDP:
	case IPPROTO_UDPLITE:
	if (nf_log_dump_udp_header(m, skb, currenthdr, fragment, ptr))
	return;
	break;
	case IPPROTO_ICMPV6: {
	struct icmp6hdr _icmp6h;
	const struct icmp6hdr *ic;

	/* Max length: 13 "PROTO=ICMPv6 " */
	nf_log_buf_add(m, "PROTO=ICMPv6 ");

	if (fragment)
	break;

	/* Max length: 25 "INCOMPLETE [65535 bytes] " */
	ic = skb_header_pointer(skb, ptr, sizeof(_icmp6h), &_icmp6h);
	if (ic == NULL) {
	nf_log_buf_add(m, "INCOMPLETE [%u bytes] ",
	skb->len - ptr);
	return;
	}

	/* Max length: 18 "TYPE=255 CODE=255 " */
	nf_log_buf_add(m, "TYPE=%u CODE=%u ",
	ic->icmp6_type, ic->icmp6_code);

	switch (ic->icmp6_type) {
	case ICMPV6_ECHO_REQUEST:
	case ICMPV6_ECHO_REPLY:
	/* Max length: 19 "ID=65535 SEQ=65535 " */
	nf_log_buf_add(m, "ID=%u SEQ=%u ",
	ntohs(ic->icmp6_identifier),
	ntohs(ic->icmp6_sequence));
	break;
	case ICMPV6_MGM_QUERY:
	case ICMPV6_MGM_REPORT:
	case ICMPV6_MGM_REDUCTION:
	break;

	case ICMPV6_PARAMPROB:
	/* Max length: 17 "POINTER=ffffffff " */
	nf_log_buf_add(m, "POINTER=%08x ",
	ntohl(ic->icmp6_pointer));
	/* Fall through */
	case ICMPV6_DEST_UNREACH:
	case ICMPV6_PKT_TOOBIG:
	case ICMPV6_TIME_EXCEED:
	/* Max length: 3+maxlen */
	if (recurse) {
	nf_log_buf_add(m, "[");
	dump_ipv6_packet(m, info, skb,
	ptr + sizeof(_icmp6h), 0);
	nf_log_buf_add(m, "] ");
	}

	/* Max length: 10 "MTU=65535 " */
	if (ic->icmp6_type == ICMPV6_PKT_TOOBIG) {
	nf_log_buf_add(m, "MTU=%u ",
	ntohl(ic->icmp6_mtu));
	}
	}
	break;
	}
	/* Max length: 10 "PROTO=255 " */
	default:
	nf_log_buf_add(m, "PROTO=%u ", currenthdr);
	}

	/* Max length: 15 "UID=4294967295 " */
	if ((logflags & XT_LOG_UID) && recurse)
	nf_log_dump_sk_uid_gid(m, skb->sk);

	/* Max length: 16 "MARK=0xFFFFFFFF " */
	if (recurse && skb->mark)
	nf_log_buf_add(m, "MARK=0x%x ", skb->mark);
	}

	static void dump_ipv6_mac_header(struct nf_log_buf *m,
	const struct nf_loginfo *info,
	const struct sk_buff *skb)
	{
	struct net_device *dev = skb->dev;
	unsigned int logflags = 0;

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

	if (!(logflags & XT_LOG_MACDECODE))
	goto fallback;

	switch (dev->type) {
	case ARPHRD_ETHER:
	nf_log_buf_add(m, "MACSRC=%pM MACDST=%pM MACPROTO=%04x ",
	eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest,
	ntohs(eth_hdr(skb)->h_proto));
	return;
	default:
	break;
	}

	fallback:
	nf_log_buf_add(m, "MAC=");
	if (dev->hard_header_len &&
	skb->mac_header != skb->network_header) {
	const unsigned char *p = skb_mac_header(skb);
	unsigned int len = dev->hard_header_len;
	unsigned int i;

	if (dev->type == ARPHRD_SIT) {
	p -= ETH_HLEN;

	if (p < skb->head)
	p = NULL;
	}

	if (p != NULL) {
	nf_log_buf_add(m, "%02x", *p++);
	for (i = 1; i < len; i++)
	nf_log_buf_add(m, ":%02x", *p++);
	}
	nf_log_buf_add(m, " ");

	if (dev->type == ARPHRD_SIT) {
	const struct iphdr *iph =
	(struct iphdr *)skb_mac_header(skb);
	nf_log_buf_add(m, "TUNNEL=%pI4->%pI4 ", &iph->saddr,
	&iph->daddr);
	}
	} else {
	nf_log_buf_add(m, " ");
	}
	}

	static void nf_log_ip6_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)
	{
	struct nf_log_buf *m;

	/* FIXME: Disabled from containers until syslog ns is supported */
	if (!net_eq(net, &init_net))
	return;

	m = nf_log_buf_open();

	if (!loginfo)
	loginfo = &default_loginfo;

	nf_log_dump_packet_common(m, pf, hooknum, skb, in, out,
	loginfo, prefix);

	if (in != NULL)
	dump_ipv6_mac_header(m, loginfo, skb);

	dump_ipv6_packet(m, loginfo, skb, skb_network_offset(skb), 1);

	nf_log_buf_close(m);
	}

	static struct nf_logger nf_ip6_logger __read_mostly = {
	.name = "nf_log_ipv6",
	.type = NF_LOG_TYPE_LOG,
	.logfn = nf_log_ip6_packet,
	.me = THIS_MODULE,
	};

	static int __net_init nf_log_ipv6_net_init(struct net *net)
	{
	nf_log_set(net, NFPROTO_IPV6, &nf_ip6_logger);
	return 0;
	}

	static void __net_exit nf_log_ipv6_net_exit(struct net *net)
	{
	nf_log_unset(net, &nf_ip6_logger);
	}

	static struct pernet_operations nf_log_ipv6_net_ops = {
	.init = nf_log_ipv6_net_init,
	.exit = nf_log_ipv6_net_exit,
	};

	static int __init nf_log_ipv6_init(void)
	{
	int ret;

	ret = register_pernet_subsys(&nf_log_ipv6_net_ops);
	if (ret < 0)
	return ret;

	ret = nf_log_register(NFPROTO_IPV6, &nf_ip6_logger);
	if (ret < 0) {
	pr_err("failed to register logger\n");
	goto err1;
	}

	return 0;

	err1:
	unregister_pernet_subsys(&nf_log_ipv6_net_ops);
	return ret;
	}

	static void __exit nf_log_ipv6_exit(void)
	{
	unregister_pernet_subsys(&nf_log_ipv6_net_ops);
	nf_log_unregister(&nf_ip6_logger);
	}

	module_init(nf_log_ipv6_init);
	module_exit(nf_log_ipv6_exit);

	MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
	MODULE_DESCRIPTION("Netfilter IPv6 packet logging");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS_NF_LOGGER(AF_INET6, 0);