netfilter: nf_nat: support IPv6 in SIP NAT helper

Add IPv6 support to the SIP NAT helper. There are no functional differences
to IPv4 NAT, just different formats for addresses.
Signed-off-by: Patrick McHardy <kaber@trash.net>

include/linux/netfilter/nf_conntrack_sip.h

@@ -99,10 +99,8 @@ enum sip_header_types {
 enum sdp_header_types {
 	SDP_HDR_UNSPEC,
 	SDP_HDR_VERSION,
-	SDP_HDR_OWNER_IP4,
-	SDP_HDR_CONNECTION_IP4,
-	SDP_HDR_OWNER_IP6,
-	SDP_HDR_CONNECTION_IP6,
+	SDP_HDR_OWNER,
+	SDP_HDR_CONNECTION,
 	SDP_HDR_MEDIA,
 };
 
@@ -111,7 +109,8 @@ extern unsigned int (*nf_nat_sip_hook)(struct sk_buff *skb,
 				       unsigned int dataoff,
 				       const char **dptr,
 				       unsigned int *datalen);
-extern void (*nf_nat_sip_seq_adjust_hook)(struct sk_buff *skb, s16 off);
+extern void (*nf_nat_sip_seq_adjust_hook)(struct sk_buff *skb,
+					  unsigned int protoff, s16 off);
 extern unsigned int (*nf_nat_sip_expect_hook)(struct sk_buff *skb,
 					      unsigned int protoff,
 					      unsigned int dataoff,

net/ipv4/netfilter/Kconfig

@@ -242,11 +242,6 @@ config NF_NAT_H323
 	depends on NF_CONNTRACK && NF_NAT_IPV4
 	default NF_NAT_IPV4 && NF_CONNTRACK_H323
 
-config NF_NAT_SIP
-	tristate
-	depends on NF_CONNTRACK && NF_NAT_IPV4
-	default NF_NAT_IPV4 && NF_CONNTRACK_SIP
-
 # mangle + specific targets
 config IP_NF_MANGLE
 	tristate "Packet mangling"

net/ipv4/netfilter/Makefile

@@ -23,7 +23,6 @@ obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o
 obj-$(CONFIG_NF_NAT_H323) += nf_nat_h323.o
 obj-$(CONFIG_NF_NAT_IRC) += nf_nat_irc.o
 obj-$(CONFIG_NF_NAT_PPTP) += nf_nat_pptp.o
-obj-$(CONFIG_NF_NAT_SIP) += nf_nat_sip.o
 obj-$(CONFIG_NF_NAT_SNMP_BASIC) += nf_nat_snmp_basic.o
 obj-$(CONFIG_NF_NAT_TFTP) += nf_nat_tftp.o
 

net/netfilter/Kconfig

@@ -390,6 +390,11 @@ config NF_NAT_FTP
 	depends on NF_CONNTRACK && NF_NAT
 	default NF_NAT && NF_CONNTRACK_FTP
 
+config NF_NAT_SIP
+	tristate
+	depends on NF_CONNTRACK && NF_NAT
+	default NF_NAT && NF_CONNTRACK_SIP
+
 endif # NF_CONNTRACK
 
 # transparent proxy support

net/netfilter/Makefile

@@ -57,6 +57,7 @@ obj-$(CONFIG_NF_NAT_PROTO_SCTP) += nf_nat_proto_sctp.o
 # NAT helpers
 obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_amanda.o
 obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
+obj-$(CONFIG_NF_NAT_SIP) += nf_nat_sip.o
 
 # transparent proxy support
 obj-$(CONFIG_NETFILTER_TPROXY) += nf_tproxy_core.o

net/netfilter/nf_conntrack_sip.c

@@ -57,7 +57,8 @@ unsigned int (*nf_nat_sip_hook)(struct sk_buff *skb, unsigned int protoff,
 				unsigned int *datalen) __read_mostly;
 EXPORT_SYMBOL_GPL(nf_nat_sip_hook);
 
-void (*nf_nat_sip_seq_adjust_hook)(struct sk_buff *skb, s16 off) __read_mostly;
+void (*nf_nat_sip_seq_adjust_hook)(struct sk_buff *skb, unsigned int protoff,
+				   s16 off) __read_mostly;
 EXPORT_SYMBOL_GPL(nf_nat_sip_seq_adjust_hook);
 
 unsigned int (*nf_nat_sip_expect_hook)(struct sk_buff *skb,
@@ -742,13 +743,18 @@ static int sdp_addr_len(const struct nf_conn *ct, const char *dptr,
  * be tolerant and also accept records terminated with a single newline
  * character". We handle both cases.
  */
-static const struct sip_header ct_sdp_hdrs[] = {
-	[SDP_HDR_VERSION]		= SDP_HDR("v=", NULL, digits_len),
-	[SDP_HDR_OWNER_IP4]		= SDP_HDR("o=", "IN IP4 ", sdp_addr_len),
-	[SDP_HDR_CONNECTION_IP4]	= SDP_HDR("c=", "IN IP4 ", sdp_addr_len),
-	[SDP_HDR_OWNER_IP6]		= SDP_HDR("o=", "IN IP6 ", sdp_addr_len),
-	[SDP_HDR_CONNECTION_IP6]	= SDP_HDR("c=", "IN IP6 ", sdp_addr_len),
-	[SDP_HDR_MEDIA]			= SDP_HDR("m=", NULL, media_len),
+static const struct sip_header ct_sdp_hdrs_v4[] = {
+	[SDP_HDR_VERSION]	= SDP_HDR("v=", NULL, digits_len),
+	[SDP_HDR_OWNER]		= SDP_HDR("o=", "IN IP4 ", sdp_addr_len),
+	[SDP_HDR_CONNECTION]	= SDP_HDR("c=", "IN IP4 ", sdp_addr_len),
+	[SDP_HDR_MEDIA]		= SDP_HDR("m=", NULL, media_len),
+};
+
+static const struct sip_header ct_sdp_hdrs_v6[] = {
+	[SDP_HDR_VERSION]	= SDP_HDR("v=", NULL, digits_len),
+	[SDP_HDR_OWNER]		= SDP_HDR("o=", "IN IP6 ", sdp_addr_len),
+	[SDP_HDR_CONNECTION]	= SDP_HDR("c=", "IN IP6 ", sdp_addr_len),
+	[SDP_HDR_MEDIA]		= SDP_HDR("m=", NULL, media_len),
 };
 
 /* Linear string search within SDP header values */
@@ -774,11 +780,14 @@ int ct_sip_get_sdp_header(const struct nf_conn *ct, const char *dptr,
 			  enum sdp_header_types term,
 			  unsigned int *matchoff, unsigned int *matchlen)
 {
-	const struct sip_header *hdr = &ct_sdp_hdrs[type];
-	const struct sip_header *thdr = &ct_sdp_hdrs[term];
+	const struct sip_header *hdrs, *hdr, *thdr;
 	const char *start = dptr, *limit = dptr + datalen;
 	int shift = 0;
 
+	hdrs = nf_ct_l3num(ct) == NFPROTO_IPV4 ? ct_sdp_hdrs_v4 : ct_sdp_hdrs_v6;
+	hdr = &hdrs[type];
+	thdr = &hdrs[term];
+
 	for (dptr += dataoff; dptr < limit; dptr++) {
 		/* Find beginning of line */
 		if (*dptr != '\r' && *dptr != '\n')
@@ -945,12 +954,12 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
 		    exp->class != class)
 			break;
 #ifdef CONFIG_NF_NAT_NEEDED
-		if (exp->tuple.src.l3num == AF_INET && !direct_rtp &&
-		    (exp->saved_addr.ip != exp->tuple.dst.u3.ip ||
+		if (!direct_rtp &&
+		    (!nf_inet_addr_cmp(&exp->saved_addr, &exp->tuple.dst.u3) ||
 		     exp->saved_proto.udp.port != exp->tuple.dst.u.udp.port) &&
 		    ct->status & IPS_NAT_MASK) {
-			daddr->ip		= exp->saved_addr.ip;
-			tuple.dst.u3.ip		= exp->saved_addr.ip;
+			*daddr			= exp->saved_addr;
+			tuple.dst.u3		= exp->saved_addr;
 			tuple.dst.u.udp.port	= exp->saved_proto.udp.port;
 			direct_rtp = 1;
 		} else
@@ -987,8 +996,7 @@ static int set_expected_rtp_rtcp(struct sk_buff *skb, unsigned int protoff,
 			  IPPROTO_UDP, NULL, &rtcp_port);
 
 	nf_nat_sdp_media = rcu_dereference(nf_nat_sdp_media_hook);
-	if (nf_nat_sdp_media && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK && !direct_rtp)
+	if (nf_nat_sdp_media && ct->status & IPS_NAT_MASK && !direct_rtp)
 		ret = nf_nat_sdp_media(skb, protoff, dataoff, dptr, datalen,
 				       rtp_exp, rtcp_exp,
 				       mediaoff, medialen, daddr);
@@ -1044,15 +1052,12 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff,
 	unsigned int i;
 	union nf_inet_addr caddr, maddr, rtp_addr;
 	unsigned int port;
-	enum sdp_header_types c_hdr;
 	const struct sdp_media_type *t;
 	int ret = NF_ACCEPT;
 	typeof(nf_nat_sdp_addr_hook) nf_nat_sdp_addr;
 	typeof(nf_nat_sdp_session_hook) nf_nat_sdp_session;
 
 	nf_nat_sdp_addr = rcu_dereference(nf_nat_sdp_addr_hook);
-	c_hdr = nf_ct_l3num(ct) == AF_INET ? SDP_HDR_CONNECTION_IP4 :
-					     SDP_HDR_CONNECTION_IP6;
 
 	/* Find beginning of session description */
 	if (ct_sip_get_sdp_header(ct, *dptr, 0, *datalen,
@@ -1066,7 +1071,7 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff,
 	 * the end of the session description. */
 	caddr_len = 0;
 	if (ct_sip_parse_sdp_addr(ct, *dptr, sdpoff, *datalen,
-				  c_hdr, SDP_HDR_MEDIA,
+				  SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
 				  &matchoff, &matchlen, &caddr) > 0)
 		caddr_len = matchlen;
 
@@ -1096,7 +1101,7 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff,
 		/* The media description overrides the session description. */
 		maddr_len = 0;
 		if (ct_sip_parse_sdp_addr(ct, *dptr, mediaoff, *datalen,
-					  c_hdr, SDP_HDR_MEDIA,
+					  SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
 					  &matchoff, &matchlen, &maddr) > 0) {
 			maddr_len = matchlen;
 			memcpy(&rtp_addr, &maddr, sizeof(rtp_addr));
@@ -1113,11 +1118,10 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff,
 			return ret;
 
 		/* Update media connection address if present */
-		if (maddr_len && nf_nat_sdp_addr &&
-		    nf_ct_l3num(ct) == NFPROTO_IPV4 && ct->status & IPS_NAT_MASK) {
+		if (maddr_len && nf_nat_sdp_addr && ct->status & IPS_NAT_MASK) {
 			ret = nf_nat_sdp_addr(skb, protoff, dataoff,
-					      dptr, datalen,
-					      mediaoff, c_hdr, SDP_HDR_MEDIA,
+					      dptr, datalen, mediaoff,
+					      SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
 					      &rtp_addr);
 			if (ret != NF_ACCEPT)
 				return ret;
@@ -1127,8 +1131,7 @@ static int process_sdp(struct sk_buff *skb, unsigned int protoff,
 
 	/* Update session connection and owner addresses */
 	nf_nat_sdp_session = rcu_dereference(nf_nat_sdp_session_hook);
-	if (nf_nat_sdp_session && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK)
+	if (nf_nat_sdp_session && ct->status & IPS_NAT_MASK)
 		ret = nf_nat_sdp_session(skb, protoff, dataoff,
 					 dptr, datalen, sdpoff, &rtp_addr);
 
@@ -1293,8 +1296,7 @@ static int process_register_request(struct sk_buff *skb, unsigned int protoff,
 	exp->flags = NF_CT_EXPECT_PERMANENT | NF_CT_EXPECT_INACTIVE;
 
 	nf_nat_sip_expect = rcu_dereference(nf_nat_sip_expect_hook);
-	if (nf_nat_sip_expect && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK)
+	if (nf_nat_sip_expect && ct->status & IPS_NAT_MASK)
 		ret = nf_nat_sip_expect(skb, protoff, dataoff, dptr, datalen,
 					exp, matchoff, matchlen);
 	else {
@@ -1476,8 +1478,7 @@ static int process_sip_msg(struct sk_buff *skb, struct nf_conn *ct,
 	else
 		ret = process_sip_response(skb, protoff, dataoff, dptr, datalen);
 
-	if (ret == NF_ACCEPT && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK) {
+	if (ret == NF_ACCEPT && ct->status & IPS_NAT_MASK) {
 		nf_nat_sip = rcu_dereference(nf_nat_sip_hook);
 		if (nf_nat_sip && !nf_nat_sip(skb, protoff, dataoff,
 					      dptr, datalen))
@@ -1560,11 +1561,10 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff,
 		datalen  = datalen + diff - msglen;
 	}
 
-	if (ret == NF_ACCEPT && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-	    ct->status & IPS_NAT_MASK) {
+	if (ret == NF_ACCEPT && ct->status & IPS_NAT_MASK) {
 		nf_nat_sip_seq_adjust = rcu_dereference(nf_nat_sip_seq_adjust_hook);
 		if (nf_nat_sip_seq_adjust)
-			nf_nat_sip_seq_adjust(skb, tdiff);
+			nf_nat_sip_seq_adjust(skb, protoff, tdiff);
 	}
 
 	return ret;

net/ipv4/netfilter/nf_nat_sip.c → net/netfilter/nf_nat_sip.c

@@ -3,7 +3,7 @@
  * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
  * based on RR's ip_nat_ftp.c and other modules.
  * (C) 2007 United Security Providers
- * (C) 2007, 2008 Patrick McHardy <kaber@trash.net>
+ * (C) 2007, 2008, 2011, 2012 Patrick McHardy <kaber@trash.net>
  *
  * 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
@@ -12,8 +12,7 @@
 
 #include <linux/module.h>
 #include <linux/skbuff.h>
-#include <linux/ip.h>
-#include <net/ip.h>
+#include <linux/inet.h>
 #include <linux/udp.h>
 #include <linux/tcp.h>
 
@@ -41,8 +40,8 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int protoff,
 	unsigned int baseoff;
 
 	if (nf_ct_protonum(ct) == IPPROTO_TCP) {
-		th = (struct tcphdr *)(skb->data + ip_hdrlen(skb));
-		baseoff = ip_hdrlen(skb) + th->doff * 4;
+		th = (struct tcphdr *)(skb->data + protoff);
+		baseoff = protoff + th->doff * 4;
 		matchoff += dataoff - baseoff;
 
 		if (!__nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
@@ -50,7 +49,7 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int protoff,
 						buffer, buflen, false))
 			return 0;
 	} else {
-		baseoff = ip_hdrlen(skb) + sizeof(struct udphdr);
+		baseoff = protoff + sizeof(struct udphdr);
 		matchoff += dataoff - baseoff;
 
 		if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo,
@@ -65,6 +64,28 @@ static unsigned int mangle_packet(struct sk_buff *skb, unsigned int protoff,
 	return 1;
 }
 
+static int sip_sprintf_addr(const struct nf_conn *ct, char *buffer,
+			    const union nf_inet_addr *addr, bool delim)
+{
+	if (nf_ct_l3num(ct) == NFPROTO_IPV4)
+		return sprintf(buffer, "%pI4", &addr->ip);
+	else {
+		if (delim)
+			return sprintf(buffer, "[%pI6c]", &addr->ip6);
+		else
+			return sprintf(buffer, "%pI6c", &addr->ip6);
+	}
+}
+
+static int sip_sprintf_addr_port(const struct nf_conn *ct, char *buffer,
+				 const union nf_inet_addr *addr, u16 port)
+{
+	if (nf_ct_l3num(ct) == NFPROTO_IPV4)
+		return sprintf(buffer, "%pI4:%u", &addr->ip, port);
+	else
+		return sprintf(buffer, "[%pI6c]:%u", &addr->ip6, port);
+}
+
 static int map_addr(struct sk_buff *skb, unsigned int protoff,
 		    unsigned int dataoff,
 		    const char **dptr, unsigned int *datalen,
@@ -74,27 +95,26 @@ static int map_addr(struct sk_buff *skb, unsigned int protoff,
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
-	char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
+	char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
 	unsigned int buflen;
-	__be32 newaddr;
+	union nf_inet_addr newaddr;
 	__be16 newport;
 
-	if (ct->tuplehash[dir].tuple.src.u3.ip == addr->ip &&
+	if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3, addr) &&
 	    ct->tuplehash[dir].tuple.src.u.udp.port == port) {
-		newaddr = ct->tuplehash[!dir].tuple.dst.u3.ip;
+		newaddr = ct->tuplehash[!dir].tuple.dst.u3;
 		newport = ct->tuplehash[!dir].tuple.dst.u.udp.port;
-	} else if (ct->tuplehash[dir].tuple.dst.u3.ip == addr->ip &&
+	} else if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, addr) &&
 		   ct->tuplehash[dir].tuple.dst.u.udp.port == port) {
-		newaddr = ct->tuplehash[!dir].tuple.src.u3.ip;
+		newaddr = ct->tuplehash[!dir].tuple.src.u3;
 		newport = ct->tuplehash[!dir].tuple.src.u.udp.port;
 	} else
 		return 1;
 
-	if (newaddr == addr->ip && newport == port)
+	if (nf_inet_addr_cmp(&newaddr, addr) && newport == port)
 		return 1;
 
-	buflen = sprintf(buffer, "%pI4:%u", &newaddr, ntohs(newport));
-
+	buflen = sip_sprintf_addr_port(ct, buffer, &newaddr, ntohs(newport));
 	return mangle_packet(skb, protoff, dataoff, dptr, datalen,
 			     matchoff, matchlen, buffer, buflen);
 }
@@ -117,7 +137,7 @@ static int map_sip_addr(struct sk_buff *skb, unsigned int protoff,
 			matchoff, matchlen, &addr, port);
 }
 
-static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sip(struct sk_buff *skb, unsigned int protoff,
 			       unsigned int dataoff,
 			       const char **dptr, unsigned int *datalen)
 {
@@ -152,16 +172,18 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff,
 				    hdr, NULL, &matchoff, &matchlen,
 				    &addr, &port) > 0) {
 		unsigned int olen, matchend, poff, plen, buflen, n;
-		char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
+		char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
 
 		/* We're only interested in headers related to this
 		 * connection */
 		if (request) {
-			if (addr.ip != ct->tuplehash[dir].tuple.src.u3.ip ||
+			if (!nf_inet_addr_cmp(&addr,
+					&ct->tuplehash[dir].tuple.src.u3) ||
 			    port != ct->tuplehash[dir].tuple.src.u.udp.port)
 				goto next;
 		} else {
-			if (addr.ip != ct->tuplehash[dir].tuple.dst.u3.ip ||
+			if (!nf_inet_addr_cmp(&addr,
+					&ct->tuplehash[dir].tuple.dst.u3) ||
 			    port != ct->tuplehash[dir].tuple.dst.u.udp.port)
 				goto next;
 		}
@@ -178,10 +200,11 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff,
 		if (ct_sip_parse_address_param(ct, *dptr, matchend, *datalen,
 					       "maddr=", &poff, &plen,
 					       &addr, true) > 0 &&
-		    addr.ip == ct->tuplehash[dir].tuple.src.u3.ip &&
-		    addr.ip != ct->tuplehash[!dir].tuple.dst.u3.ip) {
-			buflen = sprintf(buffer, "%pI4",
-					&ct->tuplehash[!dir].tuple.dst.u3.ip);
+		    nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.src.u3) &&
+		    !nf_inet_addr_cmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3)) {
+			buflen = sip_sprintf_addr(ct, buffer,
+					&ct->tuplehash[!dir].tuple.dst.u3,
+					true);
 			if (!mangle_packet(skb, protoff, dataoff, dptr, datalen,
 					   poff, plen, buffer, buflen))
 				return NF_DROP;
@@ -192,10 +215,11 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff,
 		if (ct_sip_parse_address_param(ct, *dptr, matchend, *datalen,
 					       "received=", &poff, &plen,
 					       &addr, false) > 0 &&
-		    addr.ip == ct->tuplehash[dir].tuple.dst.u3.ip &&
-		    addr.ip != ct->tuplehash[!dir].tuple.src.u3.ip) {
-			buflen = sprintf(buffer, "%pI4",
-					&ct->tuplehash[!dir].tuple.src.u3.ip);
+		    nf_inet_addr_cmp(&addr, &ct->tuplehash[dir].tuple.dst.u3) &&
+		    !nf_inet_addr_cmp(&addr, &ct->tuplehash[!dir].tuple.src.u3)) {
+			buflen = sip_sprintf_addr(ct, buffer,
+					&ct->tuplehash[!dir].tuple.src.u3,
+					false);
 			if (!mangle_packet(skb, protoff, dataoff, dptr, datalen,
 					   poff, plen, buffer, buflen))
 				return NF_DROP;
@@ -237,7 +261,8 @@ static unsigned int ip_nat_sip(struct sk_buff *skb, unsigned int protoff,
 	return NF_ACCEPT;
 }
 
-static void ip_nat_sip_seq_adjust(struct sk_buff *skb, s16 off)
+static void nf_nat_sip_seq_adjust(struct sk_buff *skb, unsigned int protoff,
+				  s16 off)
 {
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
@@ -246,12 +271,12 @@ static void ip_nat_sip_seq_adjust(struct sk_buff *skb, s16 off)
 	if (nf_ct_protonum(ct) != IPPROTO_TCP || off == 0)
 		return;
 
-	th = (struct tcphdr *)(skb->data + ip_hdrlen(skb));
+	th = (struct tcphdr *)(skb->data + protoff);
 	nf_nat_set_seq_adjust(ct, ctinfo, th->seq, off);
 }
 
 /* Handles expected signalling connections and media streams */
-static void ip_nat_sip_expected(struct nf_conn *ct,
+static void nf_nat_sip_expected(struct nf_conn *ct,
 				struct nf_conntrack_expect *exp)
 {
 	struct nf_nat_range range;
@@ -267,8 +292,8 @@ static void ip_nat_sip_expected(struct nf_conn *ct,
 
 	/* Change src to where master sends to, but only if the connection
 	 * actually came from the same source. */
-	if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip ==
-	    ct->master->tuplehash[exp->dir].tuple.src.u3.ip) {
+	if (nf_inet_addr_cmp(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3,
+			     &ct->master->tuplehash[exp->dir].tuple.src.u3)) {
 		range.flags = NF_NAT_RANGE_MAP_IPS;
 		range.min_addr = range.max_addr
 			= ct->master->tuplehash[!exp->dir].tuple.dst.u3;
@@ -276,7 +301,7 @@ static void ip_nat_sip_expected(struct nf_conn *ct,
 	}
 }
 
-static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
 				      unsigned int dataoff,
 				      const char **dptr, unsigned int *datalen,
 				      struct nf_conntrack_expect *exp,
@@ -286,16 +311,17 @@ static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
 	enum ip_conntrack_info ctinfo;
 	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
-	__be32 newip;
+	union nf_inet_addr newaddr;
 	u_int16_t port;
-	char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
+	char buffer[INET6_ADDRSTRLEN + sizeof("[]:nnnnn")];
 	unsigned int buflen;
 
 	/* Connection will come from reply */
-	if (ct->tuplehash[dir].tuple.src.u3.ip == ct->tuplehash[!dir].tuple.dst.u3.ip)
-		newip = exp->tuple.dst.u3.ip;
+	if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3,
+			     &ct->tuplehash[!dir].tuple.dst.u3))
+		newaddr = exp->tuple.dst.u3;
 	else
-		newip = ct->tuplehash[!dir].tuple.dst.u3.ip;
+		newaddr = ct->tuplehash[!dir].tuple.dst.u3;
 
 	/* If the signalling port matches the connection's source port in the
 	 * original direction, try to use the destination port in the opposite
@@ -307,10 +333,10 @@ static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
 		port = ntohs(exp->tuple.dst.u.udp.port);
 
 	exp->saved_addr = exp->tuple.dst.u3;
-	exp->tuple.dst.u3.ip = newip;
+	exp->tuple.dst.u3 = newaddr;
 	exp->saved_proto.udp.port = exp->tuple.dst.u.udp.port;
 	exp->dir = !dir;
-	exp->expectfn = ip_nat_sip_expected;
+	exp->expectfn = nf_nat_sip_expected;
 
 	for (; port != 0; port++) {
 		int ret;
@@ -328,9 +354,9 @@ static unsigned int ip_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
 	if (port == 0)
 		return NF_DROP;
 
-	if (exp->tuple.dst.u3.ip != exp->saved_addr.ip ||
+	if (!nf_inet_addr_cmp(&exp->tuple.dst.u3, &exp->saved_addr) ||
 	    exp->tuple.dst.u.udp.port != exp->saved_proto.udp.port) {
-		buflen = sprintf(buffer, "%pI4:%u", &newip, port);
+		buflen = sip_sprintf_addr_port(ct, buffer, &newaddr, port);
 		if (!mangle_packet(skb, protoff, dataoff, dptr, datalen,
 				   matchoff, matchlen, buffer, buflen))
 			goto err;
@@ -388,7 +414,7 @@ static int mangle_sdp_packet(struct sk_buff *skb, unsigned int protoff,
 			     matchoff, matchlen, buffer, buflen) ? 0 : -EINVAL;
 }
 
-static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sdp_addr(struct sk_buff *skb, unsigned int protoff,
 				    unsigned int dataoff,
 				    const char **dptr, unsigned int *datalen,
 				    unsigned int sdpoff,
@@ -396,10 +422,12 @@ static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int protoff,
 				    enum sdp_header_types term,
 				    const union nf_inet_addr *addr)
 {
-	char buffer[sizeof("nnn.nnn.nnn.nnn")];
+	enum ip_conntrack_info ctinfo;
+	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+	char buffer[INET6_ADDRSTRLEN];
 	unsigned int buflen;
 
-	buflen = sprintf(buffer, "%pI4", &addr->ip);
+	buflen = sip_sprintf_addr(ct, buffer, addr, false);
 	if (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen,
 			      sdpoff, type, term, buffer, buflen))
 		return 0;
@@ -407,7 +435,7 @@ static unsigned int ip_nat_sdp_addr(struct sk_buff *skb, unsigned int protoff,
 	return mangle_content_len(skb, protoff, dataoff, dptr, datalen);
 }
 
-static unsigned int ip_nat_sdp_port(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sdp_port(struct sk_buff *skb, unsigned int protoff,
 				    unsigned int dataoff,
 				    const char **dptr, unsigned int *datalen,
 				    unsigned int matchoff,
@@ -425,24 +453,25 @@ static unsigned int ip_nat_sdp_port(struct sk_buff *skb, unsigned int protoff,
 	return mangle_content_len(skb, protoff, dataoff, dptr, datalen);
 }
 
-static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sdp_session(struct sk_buff *skb, unsigned int protoff,
 				       unsigned int dataoff,
 				       const char **dptr, unsigned int *datalen,
 				       unsigned int sdpoff,
 				       const union nf_inet_addr *addr)
 {
-	char buffer[sizeof("nnn.nnn.nnn.nnn")];
+	enum ip_conntrack_info ctinfo;
+	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+	char buffer[INET6_ADDRSTRLEN];
 	unsigned int buflen;
 
 	/* Mangle session description owner and contact addresses */
-	buflen = sprintf(buffer, "%pI4", &addr->ip);
+	buflen = sip_sprintf_addr(ct, buffer, addr, false);
 	if (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen, sdpoff,
-			       SDP_HDR_OWNER_IP4, SDP_HDR_MEDIA,
-			       buffer, buflen))
+			      SDP_HDR_OWNER, SDP_HDR_MEDIA, buffer, buflen))
 		return 0;
 
 	switch (mangle_sdp_packet(skb, protoff, dataoff, dptr, datalen, sdpoff,
-				  SDP_HDR_CONNECTION_IP4, SDP_HDR_MEDIA,
+				  SDP_HDR_CONNECTION, SDP_HDR_MEDIA,
 				  buffer, buflen)) {
 	case 0:
 	/*
@@ -463,7 +492,7 @@ static unsigned int ip_nat_sdp_session(struct sk_buff *skb, unsigned int protoff
 
 /* So, this packet has hit the connection tracking matching code.
    Mangle it, and change the expectation to match the new version. */
-static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int protoff,
+static unsigned int nf_nat_sdp_media(struct sk_buff *skb, unsigned int protoff,
 				     unsigned int dataoff,
 				     const char **dptr, unsigned int *datalen,
 				     struct nf_conntrack_expect *rtp_exp,
@@ -478,23 +507,23 @@ static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int protoff,
 	u_int16_t port;
 
 	/* Connection will come from reply */
-	if (ct->tuplehash[dir].tuple.src.u3.ip ==
-	    ct->tuplehash[!dir].tuple.dst.u3.ip)
-		rtp_addr->ip = rtp_exp->tuple.dst.u3.ip;
+	if (nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3,
+			     &ct->tuplehash[!dir].tuple.dst.u3))
+		*rtp_addr = rtp_exp->tuple.dst.u3;
 	else
-		rtp_addr->ip = ct->tuplehash[!dir].tuple.dst.u3.ip;
+		*rtp_addr = ct->tuplehash[!dir].tuple.dst.u3;
 
 	rtp_exp->saved_addr = rtp_exp->tuple.dst.u3;
-	rtp_exp->tuple.dst.u3.ip = rtp_addr->ip;
+	rtp_exp->tuple.dst.u3 = *rtp_addr;
 	rtp_exp->saved_proto.udp.port = rtp_exp->tuple.dst.u.udp.port;
 	rtp_exp->dir = !dir;
-	rtp_exp->expectfn = ip_nat_sip_expected;
+	rtp_exp->expectfn = nf_nat_sip_expected;
 
 	rtcp_exp->saved_addr = rtcp_exp->tuple.dst.u3;
-	rtcp_exp->tuple.dst.u3.ip = rtp_addr->ip;
+	rtcp_exp->tuple.dst.u3 = *rtp_addr;
 	rtcp_exp->saved_proto.udp.port = rtcp_exp->tuple.dst.u.udp.port;
 	rtcp_exp->dir = !dir;
-	rtcp_exp->expectfn = ip_nat_sip_expected;
+	rtcp_exp->expectfn = nf_nat_sip_expected;
 
 	/* Try to get same pair of ports: if not, try to change them. */
 	for (port = ntohs(rtp_exp->tuple.dst.u.udp.port);
@@ -525,7 +554,7 @@ static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int protoff,
 
 	/* Update media port. */
 	if (rtp_exp->tuple.dst.u.udp.port != rtp_exp->saved_proto.udp.port &&
-	    !ip_nat_sdp_port(skb, protoff, dataoff, dptr, datalen,
+	    !nf_nat_sdp_port(skb, protoff, dataoff, dptr, datalen,
 			     mediaoff, medialen, port))
 		goto err2;
 
@@ -539,8 +568,8 @@ static unsigned int ip_nat_sdp_media(struct sk_buff *skb, unsigned int protoff,
 }
 
 static struct nf_ct_helper_expectfn sip_nat = {
-        .name           = "sip",
-        .expectfn       = ip_nat_sip_expected,
+	.name		= "sip",
+	.expectfn	= nf_nat_sip_expected,
 };
 
 static void __exit nf_nat_sip_fini(void)
@@ -565,13 +594,13 @@ static int __init nf_nat_sip_init(void)
 	BUG_ON(nf_nat_sdp_port_hook != NULL);
 	BUG_ON(nf_nat_sdp_session_hook != NULL);
 	BUG_ON(nf_nat_sdp_media_hook != NULL);
-	RCU_INIT_POINTER(nf_nat_sip_hook, ip_nat_sip);
-	RCU_INIT_POINTER(nf_nat_sip_seq_adjust_hook, ip_nat_sip_seq_adjust);
-	RCU_INIT_POINTER(nf_nat_sip_expect_hook, ip_nat_sip_expect);
-	RCU_INIT_POINTER(nf_nat_sdp_addr_hook, ip_nat_sdp_addr);
-	RCU_INIT_POINTER(nf_nat_sdp_port_hook, ip_nat_sdp_port);
-	RCU_INIT_POINTER(nf_nat_sdp_session_hook, ip_nat_sdp_session);
-	RCU_INIT_POINTER(nf_nat_sdp_media_hook, ip_nat_sdp_media);
+	RCU_INIT_POINTER(nf_nat_sip_hook, nf_nat_sip);
+	RCU_INIT_POINTER(nf_nat_sip_seq_adjust_hook, nf_nat_sip_seq_adjust);
+	RCU_INIT_POINTER(nf_nat_sip_expect_hook, nf_nat_sip_expect);
+	RCU_INIT_POINTER(nf_nat_sdp_addr_hook, nf_nat_sdp_addr);
+	RCU_INIT_POINTER(nf_nat_sdp_port_hook, nf_nat_sdp_port);
+	RCU_INIT_POINTER(nf_nat_sdp_session_hook, nf_nat_sdp_session);
+	RCU_INIT_POINTER(nf_nat_sdp_media_hook, nf_nat_sdp_media);
 	nf_ct_helper_expectfn_register(&sip_nat);
 	return 0;
 }