From 342daa9c9b8fe4b946b7bcd1b79e1c5ab40ef480 Mon Sep 17 00:00:00 2001
From: Maksym Sobolyev <sobomax@sippysoft.com>
Date: Wed, 29 Nov 2023 15:19:23 -0800
Subject: [PATCH] Re-work hostname validation support to not require every user
 of sockaddr_union to store a copy of the hostname.

Do this by creating a new "struct sockaddr_hu" struct,
which includes sockaddr_union as well as an optional
hostname. Extend various relevant APIs to use this
structure instead.

Untested.
---
 core_cmds.c                           |  8 ++--
 forward.c                             | 26 +++++-----
 forward.h                             | 14 +++---
 ip_addr.h                             | 69 +++++++++++++++++++--------
 modules/clusterer/clusterer.c         | 15 +++---
 modules/clusterer/topology.c          | 21 +++++---
 modules/nat_traversal/nat_traversal.c |  2 +-
 modules/nathelper/nathelper.c         |  6 ++-
 modules/proto_bin/proto_bin.c         |  9 ++--
 modules/proto_bins/proto_bins.c       |  9 ++--
 modules/proto_hep/hep.c               |  8 ++--
 modules/proto_hep/proto_hep.c         | 22 +++++----
 modules/proto_msrp/msrp_common.c      |  6 ++-
 modules/proto_msrp/msrp_common.h      |  2 +-
 modules/proto_msrp/msrp_signaling.c   | 15 ++++--
 modules/proto_sctp/sctp_server.c      |  8 ++--
 modules/proto_sctp/sctp_server.h      |  2 +-
 modules/proto_smpp/proto_smpp.c       |  4 +-
 modules/proto_smpp/smpp.c             |  6 +--
 modules/proto_ws/proto_ws.c           |  7 +--
 modules/proto_ws/ws_common.h          |  7 +--
 modules/rtpproxy/rtpproxy.c           |  4 +-
 modules/sipcapture/sipcapture.c       | 10 ++--
 modules/sl/sl_funcs.c                 |  2 +-
 modules/tcp_mgm/tcp_path.c            |  2 +-
 modules/tcp_mgm/tcp_path.h            |  2 +-
 modules/tm/dlg.h                      |  2 +-
 modules/tm/t_funcs.c                  |  4 +-
 modules/tm/t_fwd.c                    | 12 ++---
 modules/tm/t_reply.c                  |  4 +-
 modules/tm/uac.c                      | 22 ++++-----
 modules/tracer/tracer.c               | 37 +++++++-------
 modules/uac_registrant/registrant.c   | 16 +++----
 net/api_proto.h                       |  2 +-
 net/net_tcp.c                         | 17 +++++--
 net/net_tcp.h                         |  2 +-
 net/proto_tcp/proto_tcp.c             |  9 ++--
 net/proto_udp/proto_udp.c             |  5 +-
 net/tcp_common.c                      | 12 +++--
 net/tcp_common.h                      |  6 +--
 net/tcp_conn_profile.c                |  4 +-
 net/tcp_conn_profile.h                |  2 +-
 resolve.h                             |  3 +-
 sl_cb.c                               |  4 +-
 sl_cb.h                               |  6 +--
 45 files changed, 262 insertions(+), 193 deletions(-)

diff --git a/core_cmds.c b/core_cmds.c
index 32b569f0d17..c214c6403f1 100644
--- a/core_cmds.c
+++ b/core_cmds.c
@@ -745,13 +745,13 @@ static int w_forward(struct sip_msg *msg, struct proxy_l *dest)
 static int w_send(struct sip_msg *msg, struct proxy_l *dest, str *headers)
 {
 	int ret;
-	union sockaddr_union* to;
+	struct sockaddr_hu* to;
 	struct proxy_l* p;
 	int len;
 	char* tmp;
 
-	to=(union sockaddr_union*)
-			pkg_malloc(sizeof(union sockaddr_union));
+	to=(struct sockaddr_hu*)
+			pkg_malloc(sizeof(*to));
 	if (to==0){
 		LM_ERR("memory allocation failure\n");
 		return E_OUT_OF_MEM;
@@ -760,7 +760,7 @@ static int w_send(struct sip_msg *msg, struct proxy_l *dest, str *headers)
 		LM_ERR("failed to clone proxy, dropping packet\n");
 		return E_OUT_OF_MEM;
 	}
-	ret=hostent2su(to, &p->host, p->addr_idx,
+	ret=hostent2hu(to, &p->host, p->addr_idx,
 				(p->port)?p->port:SIP_PORT );
 	if (ret==0){
 		if (headers) {
diff --git a/forward.c b/forward.c
index 7a87d714c1e..e8d1308265f 100644
--- a/forward.c
+++ b/forward.c
@@ -90,7 +90,7 @@
  * be very likely noticeably slower, but it can deal better with
  * multihomed hosts
  */
-struct socket_info* get_out_socket(union sockaddr_union* to, int proto)
+struct socket_info* get_out_socket(const union sockaddr_union* to, int proto)
 {
 	int temp_sock;
 	socklen_t len;
@@ -143,7 +143,7 @@ struct socket_info* get_out_socket(union sockaddr_union* to, int proto)
  * \note if msg!=null and msg->force_send_socket, the force_send_socket will be used
  */
 struct socket_info* get_send_socket(struct sip_msg *msg,
-										union sockaddr_union* to, int proto)
+										const union sockaddr_union* to, int proto)
 {
 	struct socket_info* send_sock;
 
@@ -306,7 +306,7 @@ static inline int set_sl_branch(struct sip_msg* msg)
 
 int forward_request( struct sip_msg* msg, struct proxy_l * p)
 {
-	union sockaddr_union to;
+	struct sockaddr_hu to;
 	str buf;
 	struct socket_info* send_sock;
 	struct socket_info* last_sock;
@@ -327,17 +327,17 @@ int forward_request( struct sip_msg* msg, struct proxy_l * p)
 
 	msg_callback_process(msg, REQ_PRE_FORWARD, (void *)p);
 
-	hostent2su( &to, &p->host, p->addr_idx, (p->port)?p->port:SIP_PORT);
+	hostent2hu( &to, &p->host, p->addr_idx, (p->port)?p->port:SIP_PORT);
 	last_sock = 0;
 
 	if (getb0flags(msg) & tcp_no_new_conn_bflag)
 		tcp_no_new_conn = 1;
 
 	do {
-		send_sock=get_send_socket( msg, &to, p->proto);
+		send_sock=get_send_socket( msg, &to.su, p->proto);
 		if (send_sock==0){
 			LM_ERR("cannot forward to af %d, proto %d no corresponding"
-				"listening socket\n", to.s.sa_family, p->proto);
+				"listening socket\n", to.su.s.sa_family, p->proto);
 			ser_error=E_NO_SOCKET;
 			continue;
 		}
@@ -358,7 +358,7 @@ int forward_request( struct sip_msg* msg, struct proxy_l * p)
 			last_sock = send_sock;
 		}
 
-		if (check_blacklists( p->proto, &to, buf.s, buf.len)) {
+		if (check_blacklists( p->proto, &to.su, buf.s, buf.len)) {
 			LM_DBG("blocked by blacklists\n");
 			ser_error=E_IP_BLOCKED;
 			continue;
@@ -379,7 +379,7 @@ int forward_request( struct sip_msg* msg, struct proxy_l * p)
 		ser_error = 0;
 		break;
 
-	}while( get_next_su( p, &to, (ser_error==E_IP_BLOCKED)?0:1)==0 );
+	}while( get_next_su( p, &to.su, (ser_error==E_IP_BLOCKED)?0:1)==0 );
 
 	tcp_no_new_conn = 0;
 
@@ -402,7 +402,7 @@ int forward_request( struct sip_msg* msg, struct proxy_l * p)
 
 
 
-int update_sock_struct_from_via( union sockaddr_union* to,
+int update_sock_struct_from_via( struct sockaddr_hu* to,
 								 struct sip_msg* msg,
 								 struct via_body* via )
 {
@@ -458,7 +458,7 @@ int update_sock_struct_from_via( union sockaddr_union* to,
 		return -1;
 	}
 
-	hostent2su( to, he, 0, port);
+	hostent2hu( to, he, 0, port);
 	return 1;
 }
 
@@ -468,7 +468,7 @@ int update_sock_struct_from_via( union sockaddr_union* to,
 int forward_reply(struct sip_msg* msg)
 {
 	char* new_buf;
-	union sockaddr_union* to;
+	struct sockaddr_hu *to;
 	unsigned int new_len;
 	struct sr_module *mod;
 	int proto;
@@ -517,7 +517,7 @@ int forward_reply(struct sip_msg* msg)
 		goto error;
 	}
 
-	to=(union sockaddr_union*)pkg_malloc(sizeof(union sockaddr_union));
+	to=(struct sockaddr_hu *)pkg_malloc(sizeof(*to));
 	if (to==0){
 		LM_ERR("out of pkg memory\n");
 		goto error;
@@ -536,7 +536,7 @@ int forward_reply(struct sip_msg* msg)
 		}
 	}
 
-	send_sock = get_send_socket(msg, to, proto);
+	send_sock = get_send_socket(msg, &to->su, proto);
 
 	new_buf = build_res_buf_from_sip_res( msg, &new_len, send_sock,0);
 	if (!new_buf){
diff --git a/forward.h b/forward.h
index 37005982989..bcc26e754b0 100644
--- a/forward.h
+++ b/forward.h
@@ -48,17 +48,18 @@
 #include "socket_info.h"
 
 struct socket_info* get_send_socket(struct sip_msg* msg,
-									union sockaddr_union* su, int proto);
-struct socket_info* get_out_socket(union sockaddr_union* to, int proto);
+									const union sockaddr_union* su, int proto);
+struct socket_info* get_out_socket(const union sockaddr_union* to, int proto);
 int check_self(str* host, unsigned short port, unsigned short proto);
 int forward_request( struct sip_msg* msg,  struct proxy_l* p);
-int update_sock_struct_from_via( union sockaddr_union* to,
+int update_sock_struct_from_via( struct sockaddr_hu* to,
 								 struct sip_msg* msg,
 								 struct via_body* via );
 
 /*! \brief use src_ip, port=src_port if rport, via port if via port, 5060 otherwise */
 #define update_sock_struct_from_ip(  to, msg ) \
-	init_su((to), &(msg)->rcv.src_ip, \
+	*(to) = (struct sockaddr_hu){0}; \
+	init_su(&((to)->su), &(msg)->rcv.src_ip, \
 			((!msg->via1)||((msg)->via1->rport)||((msg)->msg_flags&FL_FORCE_RPORT))? \
 							(msg)->rcv.src_port: \
 							((msg)->via1->port)?(msg)->via1->port: SIP_PORT )
@@ -82,12 +83,13 @@ int forward_reply( struct sip_msg* msg);
  * \return 0 if ok, -1 on error
  */
 static inline int msg_send( struct socket_info* send_sock, int proto,
-							union sockaddr_union* to, unsigned int id,
+							const struct sockaddr_hu* to_hu, unsigned int id,
 							char* buf, int len, struct sip_msg* msg)
 {
 	str out_buff;
 	unsigned short port;
 	char *ip;
+	const union sockaddr_union *to = &to_hu->su;
 
 	if (proto<=PROTO_NONE || proto>=PROTO_OTHER) {
 		LM_BUG("bogus proto %s/%d received!\n",proto2a(proto),proto);
@@ -120,7 +122,7 @@ static inline int msg_send( struct socket_info* send_sock, int proto,
 	/* update the length for further processing */
 	len = out_buff.len;
 
-	if (protos[proto].tran.send(send_sock, out_buff.s, out_buff.len, to,id)<0){
+	if (protos[proto].tran.send(send_sock, out_buff.s, out_buff.len, to_hu,id)<0){
 		get_su_info(to, ip, port);
 		LM_ERR("send() to %s:%hu for proto %s/%d failed\n",
 				ip, port, proto2a(proto),proto);
diff --git a/ip_addr.h b/ip_addr.h
index 838e4c26e91..0d2684a6c6a 100644
--- a/ip_addr.h
+++ b/ip_addr.h
@@ -45,6 +45,8 @@
 
 #include "dprint.h"
 
+#define MAX_DNS_NAME 256
+
 #define MAX_RECV_BUFFER_SIZE	256*1024
 #define MAX_SEND_BUFFER_SIZE	512*1024
 #define BUFFER_INCREMENT	2048
@@ -80,22 +82,21 @@ struct net{
 	struct ip_addr mask;
 };
 
-union sockaddr_union_no_hostname{
-	struct sockaddr     s;
-	struct sockaddr_in  sin;
-	struct sockaddr_in6 sin6;
-};
+
 union sockaddr_union{
 	struct sockaddr     s;
 	struct sockaddr_in  sin;
 	struct sockaddr_in6 sin6;
-	struct {
-		union sockaddr_union_no_hostname _padding;
-		char hostname[256];
-	} h;
 };
 
-
+struct sockaddr_hu{
+	union sockaddr_union su;
+	const str_const *hp;
+	struct {
+		str_const hoststr;
+		char hostname[MAX_DNS_NAME];
+	} _;
+};
 
 enum si_flags { SI_NONE=0, SI_IS_IP=1, SI_IS_LO=2, SI_IS_MCAST=4,
 	SI_IS_ANYCAST=8, SI_FRAG=16, SI_REUSEPORT=32 };
@@ -117,7 +118,7 @@ struct receive_info {
 struct dest_info {
 	int proto;
 	unsigned int proto_reserved1; /*!< tcp stores the connection id here */
-	union sockaddr_union to;
+	struct sockaddr_hu to;
 	struct socket_info* send_sock;
 };
 
@@ -221,7 +222,7 @@ inline static int matchnet(struct ip_addr* ip, struct net* net)
 
 
 /*! \brief inits an ip_addr pointer from a sockaddr structure*/
-static inline void sockaddr2ip_addr(struct ip_addr* ip, struct sockaddr* sa)
+static inline void sockaddr2ip_addr(struct ip_addr* ip, const struct sockaddr* sa)
 {
 	void *copyfrom;
 
@@ -275,7 +276,7 @@ static inline int su_cmp(union sockaddr_union* s1, union sockaddr_union* s2)
 
 
 /*! \brief gets the port number (host byte order) */
-static inline unsigned short su_getport(union sockaddr_union* su)
+static inline unsigned short su_getport(const union sockaddr_union* su)
 {
 	if(su==0)
 		return 0;
@@ -307,7 +308,7 @@ static inline void su_setport(union sockaddr_union* su, unsigned short port)
 }
 
 /*! \brief inits an ip_addr pointer from a sockaddr_union ip address */
-static inline void su2ip_addr(struct ip_addr* ip, union sockaddr_union* su)
+static inline void su2ip_addr(struct ip_addr* ip, const union sockaddr_union* su)
 {
 	switch(su->s.sa_family){
 	case AF_INET:
@@ -368,17 +369,13 @@ static inline int init_su( union sockaddr_union* su,
  * the hostent structure and a port no. (host byte order)
  * WARNING: no index overflow  checks!
  * \return 0 if ok, -1 on error (unknown address family) */
-static inline int hostent2su( union sockaddr_union* su,
-								struct hostent* he,
+static inline int hostent2su( union sockaddr_union *su,
+								const struct hostent* he,
 								unsigned int idx,
 								unsigned short   port )
 {
 	memset(su, 0, sizeof(union sockaddr_union)); /*needed on freebsd*/
 
-	/* copy the hostname into the sockaddr_union */
-	strncpy(su->h.hostname, he->h_name, sizeof(su->h.hostname)-1);
-	su->h.hostname[sizeof(su->h.hostname)-1] = 0;
-
 	su->s.sa_family=he->h_addrtype;
 	switch(he->h_addrtype){
 	case	AF_INET6:
@@ -402,6 +399,38 @@ static inline int hostent2su( union sockaddr_union* su,
 	return 0;
 }
 
+static inline int hostent2hu( struct sockaddr_hu *hu,
+								struct hostent* he,
+								unsigned int idx,
+								unsigned short   port )
+{
+	union sockaddr_union* su = &hu->su;
+	size_t nlen = strlen(he->h_name);
+
+	if (nlen >= sizeof(hu->_.hostname)) {
+		LM_CRIT("Hostname is too long: \"%s\"", he->h_name);
+		return -1;
+	}
+
+	int r = hostent2su(su, he, idx, port);
+
+	if (r == 0) {
+		memcpy(hu->_.hostname, he->h_name, nlen);
+		hu->_.hostname[nlen] = 0;
+		hu->_.hoststr.s = hu->_.hostname;
+		hu->_.hoststr.len = nlen;
+		hu->hp = &hu->_.hoststr;
+	}
+	return 0;
+}
+
+static inline void hu_dup(const struct sockaddr_hu *hu_s, struct sockaddr_hu *hu_d)
+{
+	memcpy(hu_d, hu_s, sizeof(*hu_d));
+	hu_d->_.hoststr.s = hu_d->_.hostname;
+	hu_d->hp = &hu_d->_.hoststr;
+}
+
 /*! \brief maximum size of a str returned by ip_addr2a (including \\0') */
 #define IP_ADDR_MAX_STR_SIZE 40 /* 1234:5678:9012:3456:7890:1234:5678:9012\0 */
 #define IP_ADDR2STR_BUF_NO 4
diff --git a/modules/clusterer/clusterer.c b/modules/clusterer/clusterer.c
index 93636e22e94..3ff5f36d6e7 100644
--- a/modules/clusterer/clusterer.c
+++ b/modules/clusterer/clusterer.c
@@ -322,8 +322,9 @@ static int msg_send_retry(bin_packet_t *packet, node_info_t *dest,
 		}
 		bin_get_buffer(packet, &send_buffer);
 
+		struct sockaddr_hu to = {.su = chosen_dest->addr};
 		if (msg_send(chosen_dest->cluster->send_sock, chosen_dest->proto,
-			&chosen_dest->addr, 0, send_buffer.s, send_buffer.len, 0) < 0) {
+			&to, 0, send_buffer.s, send_buffer.len, 0) < 0) {
 			LM_ERR("msg_send() to node [%d] failed\n", chosen_dest->node_id);
 			retr_send = 1;
 
@@ -1474,15 +1475,17 @@ int send_single_cap_update(cluster_info_t *cluster, struct local_cap *cap,
 	bin_push_int(&packet, current_id);
 	bin_get_buffer(&packet, &bin_buffer);
 
-	for (i = 0; i < no_dests; i++)
+	for (i = 0; i < no_dests; i++) {
+		struct sockaddr_hu to = {.su = destinations[i]->addr};
 		if (msg_send(cluster->send_sock, destinations[i]->proto,
-			&destinations[i]->addr, 0, bin_buffer.s, bin_buffer.len, 0) < 0) {
+			&to, 0, bin_buffer.s, bin_buffer.len, 0) < 0) {
 			LM_ERR("Failed to send capability update to node [%d]\n",
 				destinations[i]->node_id);
 			set_link_w_neigh_adv(-1, LS_RESTART_PINGING, destinations[i]);
 		} else
 			LM_DBG("Sent capability update to node [%d]\n",
 				destinations[i]->node_id);
+	}
 
 	bin_free_packet(&packet);
 
@@ -1567,8 +1570,8 @@ int send_cap_update(node_info_t *dest_node, int require_reply)
 	bin_push_int(&packet, 1);	/* path length is 1, only current node at this point */
 	bin_push_int(&packet, current_id);
 	bin_get_buffer(&packet, &bin_buffer);
-
-	if (msg_send(dest_node->cluster->send_sock, dest_node->proto, &dest_node->addr,
+	struct sockaddr_hu to = {.su = dest_node->addr};
+	if (msg_send(dest_node->cluster->send_sock, dest_node->proto, &to,
 		0, bin_buffer.s, bin_buffer.len, 0) < 0) {
 		LM_ERR("Failed to send capability update to node [%d]\n", dest_node->node_id);
 		set_link_w_neigh_adv(-1, LS_RESTART_PINGING, dest_node);
@@ -1851,4 +1854,4 @@ unsigned long clusterer_get_num_nodes(int state)
 	lock_stop_read(cl_list_lock);
 
 	return nodecount;
-}
\ No newline at end of file
+}
diff --git a/modules/clusterer/topology.c b/modules/clusterer/topology.c
index e5fe1e94d44..0eada0af801 100644
--- a/modules/clusterer/topology.c
+++ b/modules/clusterer/topology.c
@@ -57,7 +57,8 @@ static int send_ping(node_info_t *node, int req_node_list)
 	set_proc_log_level(L_INFO);
 	#endif
 
-	rc = msg_send(node->cluster->send_sock, node->proto, &node->addr, 0,
+	struct sockaddr_hu to = {.su = node->addr};
+	rc = msg_send(node->cluster->send_sock, node->proto, &to, 0,
 		send_buffer.s, send_buffer.len, 0);
 
 	#ifndef CLUSTERER_EXTRA_BIN_DBG
@@ -487,8 +488,9 @@ int flood_message(bin_packet_t *packet, cluster_info_t *cluster,
 	lock_release(cluster->current_node->lock);
 
 	for (i = 0; i < no_dests; i++) {
+		struct sockaddr_hu to = {.su = destinations[i]->addr};
 		if (msg_send(cluster->send_sock, destinations[i]->proto,
-			&destinations[i]->addr, 0, bin_buffer.s, bin_buffer.len, 0) < 0) {
+			&to, 0, bin_buffer.s, bin_buffer.len, 0) < 0) {
 			LM_ERR("Failed to flood message to node [%d]\n",
 				destinations[i]->node_id);
 
@@ -601,7 +603,8 @@ static int send_full_top_update(node_info_t *dest_node, int nr_nodes, int *node_
 	bin_push_int(&packet, current_id);
 	bin_get_buffer(&packet, &bin_buffer);
 
-	if (msg_send(dest_node->cluster->send_sock, dest_node->proto, &dest_node->addr,
+	struct sockaddr_hu to = {.su = dest_node->addr};
+	if (msg_send(dest_node->cluster->send_sock, dest_node->proto, &to,
 		0, bin_buffer.s, bin_buffer.len, 0) < 0) {
 		LM_ERR("Failed to send topology update to node [%d]\n", dest_node->node_id);
 		set_link_w_neigh_adv(-1, LS_RESTART_PINGING, dest_node);
@@ -662,8 +665,9 @@ static int send_ls_update(node_info_t *node, clusterer_link_state new_ls)
 
 	bin_get_buffer(&packet, &send_buffer);
 	for (i = 0; i < no_dests; i++) {
+		struct sockaddr_hu to = {.su = destinations[i]->addr};
 		if (msg_send(destinations[i]->cluster->send_sock, destinations[i]->proto,
-			&destinations[i]->addr, 0, send_buffer.s, send_buffer.len, 0) < 0) {
+			&to, 0, send_buffer.s, send_buffer.len, 0) < 0) {
 			LM_ERR("Failed to send link state update to node [%d]\n",
 				destinations[i]->node_id);
 			/* this node was supposed to be up, restart pinging */
@@ -1144,7 +1148,8 @@ void handle_internal_msg_unknown(bin_packet_t *received, cluster_info_t *cl,
 		bin_push_int(&packet, current_id);
 		bin_get_buffer(&packet, &bin_buffer);
 
-		if (msg_send(cl->send_sock, proto, src_su, 0, bin_buffer.s,
+		struct sockaddr_hu to = {.su = *src_su};
+		if (msg_send(cl->send_sock, proto, &to, 0, bin_buffer.s,
 			bin_buffer.len, 0) < 0)
 			LM_ERR("Failed to reply to ping from unknown node, id [%d]\n", src_node_id);
 		else
@@ -1247,7 +1252,8 @@ void handle_unknown_id(node_info_t *src_node)
 	bin_push_int(&packet, current_id);
 
 	bin_get_buffer(&packet, &bin_buffer);
-	if (msg_send(src_node->cluster->send_sock, src_node->proto, &src_node->addr,
+	struct sockaddr_hu to = {.su = src_node->addr};
+	if (msg_send(src_node->cluster->send_sock, src_node->proto, &to,
 		0, bin_buffer.s, bin_buffer.len, 0) < 0)
 		LM_ERR("Failed to send node description to node [%d]\n", src_node->node_id);
 	else
@@ -1294,8 +1300,9 @@ void handle_ping(bin_packet_t *received, node_info_t *src_node,
 	set_proc_log_level(L_INFO);
 	#endif
 
+	struct sockaddr_hu to = {.su = src_node->addr};
 	send_rc = msg_send(src_node->cluster->send_sock, src_node->proto,
-		&src_node->addr, 0, bin_buffer.s, bin_buffer.len, 0);
+		&to, 0, bin_buffer.s, bin_buffer.len, 0);
 
 	#ifndef CLUSTERER_EXTRA_BIN_DBG
 	reset_proc_log_level();
diff --git a/modules/nat_traversal/nat_traversal.c b/modules/nat_traversal/nat_traversal.c
index 6ee94a7de87..0ced5a45f43 100644
--- a/modules/nat_traversal/nat_traversal.c
+++ b/modules/nat_traversal/nat_traversal.c
@@ -1189,7 +1189,7 @@ __dialog_destroy(struct dlg_cell *dlg, int type, struct dlg_cb_params *_params)
 //
 static void
 __sl_reply_out(struct sip_msg* request, str *buffer, int rpl_code,
-                union sockaddr_union *dst, struct socket_info *sock, int proto)
+                const struct sockaddr_hu *dst, struct socket_info *sock, int proto)
 {
     struct sip_msg reply;
     time_t expire;
diff --git a/modules/nathelper/nathelper.c b/modules/nathelper/nathelper.c
index d41ad2e23b1..50ee207ef96 100644
--- a/modules/nathelper/nathelper.c
+++ b/modules/nathelper/nathelper.c
@@ -1423,7 +1423,8 @@ nh_timer(unsigned int ticks, void *timer_idx)
 			if ((flags & sipping_flag) &&
 			    (opt.s = build_sipping(d, &c, send_sock, &path, &opt.len,
 			                         ct_coords, flags))) {
-				if (msg_send(send_sock, next_hop.proto, &to, 0, opt.s, opt.len, NULL) < 0) {
+				struct sockaddr_hu to_hu = {.su = to};
+				if (msg_send(send_sock, next_hop.proto, &to_hu, 0, opt.s, opt.len, NULL) < 0) {
 					LM_ERR("sip msg_send failed\n");
 				}
 			} else if (raw_ip && next_hop.proto == PROTO_UDP) {
@@ -1431,7 +1432,8 @@ nh_timer(unsigned int ticks, void *timer_idx)
 					LM_ERR("send_raw failed\n");
 				}
 			} else {
-				if (msg_send(send_sock, next_hop.proto, &to, 0,
+				struct sockaddr_hu to_hu = {.su = to};
+				if (msg_send(send_sock, next_hop.proto, &to_hu, 0,
 				             (char *)sbuf, sizeof(sbuf), NULL) < 0) {
 					LM_ERR("sip msg_send failed!\n");
 				}
diff --git a/modules/proto_bin/proto_bin.c b/modules/proto_bin/proto_bin.c
index 312696f4421..5d2cd3c5630 100644
--- a/modules/proto_bin/proto_bin.c
+++ b/modules/proto_bin/proto_bin.c
@@ -47,7 +47,7 @@ static int mod_init(void);
 static int proto_bin_init(struct proto_info *pi);
 static int proto_bin_init_listener(struct socket_info *si);
 static int proto_bin_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int bin_read_req(struct tcp_connection* con, int* bytes_read);
 
@@ -142,13 +142,14 @@ static int proto_bin_init_listener(struct socket_info *si)
 }
 
 static int proto_bin_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu *to_hu,
 		unsigned int id)
 {
 	struct tcp_connection *c;
 	struct ip_addr ip;
 	int port;
 	int fd, n;
+	const union sockaddr_union *to = to_hu ? &to_hu->su : NULL;
 
 	port=0;
 
@@ -184,7 +185,7 @@ static int proto_bin_send(struct socket_info* send_sock,
 		LM_DBG("no open tcp connection found, opening new one, async = %d\n",bin_async);
 		/* create tcp connection */
 		if (bin_async) {
-			n = tcp_async_connect(send_sock, to, &prof,
+			n = tcp_async_connect(send_sock, to_hu, &prof,
 					bin_async_local_connect_timeout, &c, &fd, 1);
 			if ( n<0 ) {
 				LM_ERR("async TCP connect failed\n");
@@ -211,7 +212,7 @@ static int proto_bin_send(struct socket_info* send_sock,
 				return len;
 			}
 			/* our first connect attempt succeeded - go ahead as normal */
-		} else if ((c=tcp_sync_connect(send_sock, to, &prof, &fd, 1))==0) {
+		} else if ((c=tcp_sync_connect(send_sock, to_hu, &prof, &fd, 1))==0) {
 			LM_ERR("connect failed\n");
 			return -1;
 		}
diff --git a/modules/proto_bins/proto_bins.c b/modules/proto_bins/proto_bins.c
index a823cc497f2..45c8753a214 100644
--- a/modules/proto_bins/proto_bins.c
+++ b/modules/proto_bins/proto_bins.c
@@ -46,7 +46,7 @@ static int mod_init(void);
 static int proto_bins_init(struct proto_info *pi);
 static int proto_bins_init_listener(struct socket_info *si);
 static int proto_bins_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int bins_read_req(struct tcp_connection* con, int* bytes_read);
 static int bins_async_write(struct tcp_connection* con,int fd);
@@ -337,7 +337,7 @@ static int bins_write_on_socket(struct tcp_connection* c, int fd,
 }
 
 static int proto_bins_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to_hu,
 		unsigned int id)
 {
 	struct tcp_connection *c;
@@ -345,6 +345,7 @@ static int proto_bins_send(struct socket_info* send_sock,
 	int port;
 	int fd, n;
 	int send2main = 0;
+	const union sockaddr_union *to = to_hu ? &to_hu->su : NULL;
 
 	port=0;
 
@@ -381,7 +382,7 @@ static int proto_bins_send(struct socket_info* send_sock,
 			bins_async);
 		/* create tcp connection */
 		if (bins_async) {
-			n = tcp_async_connect(send_sock, to, &prof,
+			n = tcp_async_connect(send_sock, to_hu, &prof,
 					bins_async_local_connect_timeout, &c, &fd, 1);
 			if ( n<0 ) {
 				LM_ERR("async TCP connect failed\n");
@@ -438,7 +439,7 @@ static int proto_bins_send(struct socket_info* send_sock,
 			LM_DBG("First TLS handshake attempt succeeded in less than %dms, "
 				"proceed to writing \n",bins_async_handshake_connect_timeout);
 		} else {
-			if ((c=tcp_sync_connect(send_sock, to, &prof, &fd, 0))==0) {
+			if ((c=tcp_sync_connect(send_sock, to_hu, &prof, &fd, 0))==0) {
 				LM_ERR("connect failed\n");
 				return -1;
 			}
diff --git a/modules/proto_hep/hep.c b/modules/proto_hep/hep.c
index f286c00f37b..64cc81f7fc1 100644
--- a/modules/proto_hep/hep.c
+++ b/modules/proto_hep/hep.c
@@ -1684,7 +1684,7 @@ int send_hep_message(trace_message message, trace_dest dest, struct socket_info*
 	char* buf=0;
 
 	struct proxy_l* p;
-	union sockaddr_union* to;
+	struct sockaddr_hu* to;
 
 	hid_list_p hep_dest = (hid_list_p) dest;
 
@@ -1715,7 +1715,7 @@ int send_hep_message(trace_message message, trace_dest dest, struct socket_info*
 		goto end;
 	}
 
-	to=(union sockaddr_union *)pkg_malloc(sizeof(union sockaddr_union));
+	to=(struct sockaddr_hu *)pkg_malloc(sizeof(*to));
 	if (to == 0) {
 		LM_ERR("no more pkg mem!\n");
 		pkg_free(buf);
@@ -1724,7 +1724,7 @@ int send_hep_message(trace_message message, trace_dest dest, struct socket_info*
 		goto end;
 	}
 
-	hostent2su(to, &p->host, p->addr_idx, p->port?p->port:HEP_PORT);
+	hostent2hu(to, &p->host, p->addr_idx, p->port?p->port:HEP_PORT);
 
 	do {
 		if (msg_send(send_sock, hep_dest->transport, to, 0, buf, len, NULL) < 0) {
@@ -1733,7 +1733,7 @@ int send_hep_message(trace_message message, trace_dest dest, struct socket_info*
 		}
 		ret=0;
 		break;
-	} while ( get_next_su( p, to, 0)==0);
+	} while ( get_next_su( p, &to->su, 0)==0);
 
 	free_proxy(p);
 	pkg_free(p);
diff --git a/modules/proto_hep/proto_hep.c b/modules/proto_hep/proto_hep.c
index eed77381faf..c7827aa5a3b 100644
--- a/modules/proto_hep/proto_hep.c
+++ b/modules/proto_hep/proto_hep.c
@@ -61,16 +61,16 @@ static int hep_tcp_or_tls_read_req(struct tcp_connection* con, int* bytes_read,
 		unsigned int is_tls);
 static int hep_udp_read_req(struct socket_info* si, int* bytes_read);
 static int hep_udp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int hep_tcp_or_tls_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id, unsigned int is_tls);
 static int hep_tcp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int hep_tls_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static void update_recv_info(struct receive_info* ri, struct hep_desc* h);
 void free_hep_context(void* ptr);
@@ -345,10 +345,11 @@ static int proto_hep_init_udp_listener(struct socket_info* si)
 }
 
 static int hep_udp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to_hu,
 		unsigned int id)
 {
 	int n, tolen;
+	const union sockaddr_union *to = &to_hu->su;
 	tolen = sockaddru_len(*to);
 
 again:
@@ -367,27 +368,28 @@ static int hep_udp_send(struct socket_info* send_sock,
 }
 
 static int hep_tcp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id)
 {
 	return hep_tcp_or_tls_send(send_sock, buf, len, to, id, 0);
 }
 
 static int hep_tls_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id)
 {
 	return hep_tcp_or_tls_send(send_sock, buf, len, to, id, 1);
 }
 
 static int hep_tcp_or_tls_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to_hu,
 		unsigned int id, unsigned int is_tls)
 {
 	struct tcp_connection* c;
 	int port = 0;
 	struct ip_addr ip;
 	int fd, n;
+	const union sockaddr_union* to = to_hu ? &to_hu->su : NULL;
 
 	if (to) {
 		su2ip_addr(&ip, to);
@@ -421,7 +423,7 @@ static int hep_tcp_or_tls_send(struct socket_info* send_sock,
 		LM_DBG("no open tcp connection found, opening new one, async = %d\n", hep_async);
 		/* create tcp connection */
 		if (hep_async) {
-			n = tcp_async_connect(send_sock, to, &prof,
+			n = tcp_async_connect(send_sock, to_hu, &prof,
 					hep_async_local_connect_timeout, &c, &fd, 1);
 			if (n < 0) {
 				LM_ERR("async TCP connect failed\n");
@@ -479,7 +481,7 @@ static int hep_tcp_or_tls_send(struct socket_info* send_sock,
 				LM_DBG("first TLS handshake attempt succeeded in less than %dms, "
 					"proceed to writing \n", hep_tls_async_handshake_connect_timeout);
 			}
-		} else if ((c = tcp_sync_connect(send_sock, to, &prof, &fd, 1)) == 0) {
+		} else if ((c = tcp_sync_connect(send_sock, to_hu, &prof, &fd, 1)) == 0) {
 			LM_ERR("connect failed\n");
 			return -1;
 		}
diff --git a/modules/proto_msrp/msrp_common.c b/modules/proto_msrp/msrp_common.c
index d0cd4626433..10a51b659f8 100644
--- a/modules/proto_msrp/msrp_common.c
+++ b/modules/proto_msrp/msrp_common.c
@@ -30,6 +30,7 @@
 #include "../../ut.h"
 #include "../../net/trans_trace.h"
 #include "../../net/tcp_common.h"
+#include "../../timer.h"
 #include "msrp_handler.h"
 #include "msrp_plain.h"
 #include "msrp_common.h"
@@ -557,7 +558,7 @@ int msrp_read_req(struct tcp_connection* con, int* bytes_read)
 /*! \brief Finds a tcpconn & sends on it */
 int proto_msrp_send(struct socket_info* send_sock,
 		char* buf, unsigned int len,
-		union sockaddr_union* to, unsigned int id)
+		const struct sockaddr_hu* to_hu, unsigned int id)
 {
 	struct tcp_connection *c;
 	struct tcp_conn_profile prof;
@@ -566,6 +567,7 @@ int proto_msrp_send(struct socket_info* send_sock,
 	union sockaddr_union src_su, dst_su;
 	int port = 0, fd, n, matched;
 	struct tls_domain *dom;
+	const union sockaddr_union *to = to_hu ? &to_hu->su : NULL;
 
 	matched = tcp_con_get_profile(to, &send_sock->su, send_sock->proto, &prof);
 
@@ -606,7 +608,7 @@ int proto_msrp_send(struct socket_info* send_sock,
 		}
 		LM_DBG("no open tcp connection found, opening new one\n");
 		/* create tcp connection */
-		if ((c=tcp_sync_connect(send_sock, to, &prof, &fd, 1))==0) {
+		if ((c=tcp_sync_connect(send_sock, to_hu, &prof, &fd, 1))==0) {
 			LM_ERR("connect failed\n");
 			get_time_difference(get,prof.send_threshold,tcp_timeout_con_get);
 			return -1;
diff --git a/modules/proto_msrp/msrp_common.h b/modules/proto_msrp/msrp_common.h
index db33a9625b4..658f8f64173 100644
--- a/modules/proto_msrp/msrp_common.h
+++ b/modules/proto_msrp/msrp_common.h
@@ -86,7 +86,7 @@ void msrp_brief_parse_msg(struct msrp_req *r);
 
 int proto_msrp_send(struct socket_info* send_sock,
 		char* buf, unsigned int len,
-		union sockaddr_union* to, unsigned int id);
+		const struct sockaddr_hu* to, unsigned int id);
 
 int msrp_read_req(struct tcp_connection* con, int* bytes_read);
 
diff --git a/modules/proto_msrp/msrp_signaling.c b/modules/proto_msrp/msrp_signaling.c
index 901fb25ab96..4a90db5d4ff 100644
--- a/modules/proto_msrp/msrp_signaling.c
+++ b/modules/proto_msrp/msrp_signaling.c
@@ -190,8 +190,9 @@ int msrp_send_reply( void *hdl, struct msrp_msg *req, int code, str* reason,
 	}
 
 	/* now, send it out*/
+	struct sockaddr_hu to = {.su = req->rcv.src_su};
 	i = msg_send( req->rcv.bind_address, PROTO_MSRP,
-			&req->rcv.src_su, req->rcv.proto_reserved1,
+			&to, req->rcv.proto_reserved1,
 			buf, len, NULL);
 	if (i<0) {
 		/* sending failed, FIXME - close the connection */
@@ -424,7 +425,8 @@ int msrp_fwd_request( void *hdl, struct msrp_msg *req, str *hdrs, int hdrs_no,
 	}
 
 	/* now, send it out*/
-	i = msg_send( sock, sock->proto, to_su , 0 /*conn-id*/, buf, len, NULL);
+	struct sockaddr_hu to_hu = {.su = *to_su};
+	i = msg_send( sock, sock->proto, &to_hu , 0 /*conn-id*/, buf, len, NULL);
 	if (i<0) {
 		/* sending failed, TODO - close the connection */
 		LM_ERR("failed to fwd MSRP request\n");
@@ -789,8 +791,9 @@ int msrp_send_report(void *hdl, str *status,
 				&cell->recv.to, cell->recv.proto_reserved1,
 				buf, len, NULL);
 	} else {
+		struct sockaddr_hu to = {.su = req->rcv.src_su};
 		i = msg_send( req->rcv.bind_address, PROTO_MSRP,
-				&req->rcv.src_su, req->rcv.proto_reserved1,
+				&to, req->rcv.proto_reserved1,
 				buf, len, NULL);
 	}
 	if (i<0) {
@@ -1054,7 +1057,8 @@ int msrp_send_request(void *hdl, enum msrp_method method_id,
 	}
 
 	/* now, send it out*/
-	i = msg_send( sock, sock->proto, to_su, 0 /*conn-id*/, buf, len, NULL);
+	struct sockaddr_hu to_hu = {.su = *to_su};
+	i = msg_send( sock, sock->proto, &to_hu, 0 /*conn-id*/, buf, len, NULL);
 	if (i<0) {
 		/* sending failed, TODO - close the connection */
 		LM_ERR("failed to fwd MSRP request\n");
@@ -1280,7 +1284,8 @@ static struct msrp_cell* _build_transaction(struct msrp_msg *req, int hash,
 				req->failure_report->body.len);
 		}
 
-		init_su( &cell->recv.to, &req->rcv.src_ip, req->rcv.src_port);
+		cell->recv.to = (struct sockaddr_hu){0};
+		init_su( &cell->recv.to.su, &req->rcv.src_ip, req->rcv.src_port);
 		cell->recv.proto = req->rcv.proto;
 		cell->recv.proto_reserved1 = req->rcv.proto_reserved1;
 		cell->recv.send_sock = req->rcv.bind_address;
diff --git a/modules/proto_sctp/sctp_server.c b/modules/proto_sctp/sctp_server.c
index e48f4d56be7..0696f44d362 100644
--- a/modules/proto_sctp/sctp_server.c
+++ b/modules/proto_sctp/sctp_server.c
@@ -190,20 +190,20 @@ int proto_sctp_read(struct socket_info *si, int* bytes_read)
 
 /*! \brief which socket to use? main socket or new one? */
 int proto_sctp_send(struct socket_info *source, char *buf, unsigned len,
-									union sockaddr_union* to, unsigned int id)
+									const struct sockaddr_hu *to, unsigned int id)
 {
 	int n;
 	int tolen;
 
-	tolen=sockaddru_len(*to);
+	tolen=sockaddru_len(to->su);
 again:
-	n=sctp_sendmsg(source->socket, buf, len, &to->s, tolen, 0, 0, 0, 0, 0);
+	n=sctp_sendmsg(source->socket, buf, len, &to->su.s, tolen, 0, 0, 0, 0, 0);
 #ifdef XL_DEBUG
 	LM_INFO("send status: %d\n", n);
 #endif
 	if (n==-1){
 		LM_ERR("sctp_sendmsg(sock,%p,%d,%p,%d,0,0,0,0,0): %s(%d)\n",
-				buf,len,&to->s,tolen, strerror(errno),errno);
+				buf,len,&to->su.s,tolen, strerror(errno),errno);
 
 		if (errno==EINTR) goto again;
 		if (errno==EINVAL) {
diff --git a/modules/proto_sctp/sctp_server.h b/modules/proto_sctp/sctp_server.h
index 57700703f4f..edc0e831620 100644
--- a/modules/proto_sctp/sctp_server.h
+++ b/modules/proto_sctp/sctp_server.h
@@ -37,7 +37,7 @@
 int proto_sctp_init_listener(struct socket_info* si);
 
 int proto_sctp_send(struct socket_info *source, char *buf, unsigned len,
-		union sockaddr_union* to, unsigned int id);
+		const struct sockaddr_hu* to, unsigned int id);
 
 int proto_sctp_read(struct socket_info *si, int* bytes_read);
 
diff --git a/modules/proto_smpp/proto_smpp.c b/modules/proto_smpp/proto_smpp.c
index a43776f91c0..b7a3fe37ffb 100644
--- a/modules/proto_smpp/proto_smpp.c
+++ b/modules/proto_smpp/proto_smpp.c
@@ -60,7 +60,7 @@ static int child_init(int rank);
 static int smpp_init(struct proto_info *pi);
 static int smpp_init_listener(struct socket_info *si);
 static int smpp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int smpp_read_req(struct tcp_connection* conn, int* bytes_read);
 static int smpp_write_async_req(struct tcp_connection* con,int fd);
@@ -230,7 +230,7 @@ static int smpp_init_listener(struct socket_info *si)
 }
 
 static int smpp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id)
 {
 	LM_INFO("smpp_send called\n");
diff --git a/modules/proto_smpp/smpp.c b/modules/proto_smpp/smpp.c
index afb86fbf4fe..aa4fdfe7223 100644
--- a/modules/proto_smpp/smpp.c
+++ b/modules/proto_smpp/smpp.c
@@ -791,7 +791,7 @@ int send_outbind(smpp_session_t *session)
 static struct tcp_connection *smpp_connect(smpp_session_t *session, int *fd)
 {
 	union sockaddr_union to;
-	union sockaddr_union server;
+	struct sockaddr_hu server = {0};
 	struct socket_info *send_socket;
 	struct tcp_conn_profile prof;
 
@@ -799,7 +799,7 @@ static struct tcp_connection *smpp_connect(smpp_session_t *session, int *fd)
 		LM_ERR("error creating su from ipaddr and port\n");
 		return NULL;
 	}
-	if (init_su(&server, &session->ip, session->port)) {
+	if (init_su(&server.su, &session->ip, session->port)) {
 		LM_ERR("error creating su from ipaddr and port\n");
 		return NULL;
 	}
@@ -809,7 +809,7 @@ static struct tcp_connection *smpp_connect(smpp_session_t *session, int *fd)
 		return NULL;
 	}
 
-	tcp_con_get_profile(&server, &send_socket->su, PROTO_SMPP, &prof);
+	tcp_con_get_profile(&server.su, &send_socket->su, PROTO_SMPP, &prof);
 
 	return tcp_sync_connect(send_socket, &server, &prof, fd, 1);
 }
diff --git a/modules/proto_ws/proto_ws.c b/modules/proto_ws/proto_ws.c
index ee73bbfc16d..bfa63c45490 100644
--- a/modules/proto_ws/proto_ws.c
+++ b/modules/proto_ws/proto_ws.c
@@ -95,7 +95,7 @@ static int mod_init(void);
 static int proto_ws_init(struct proto_info *pi);
 static int proto_ws_init_listener(struct socket_info *si);
 static int proto_ws_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 static int ws_read_req(struct tcp_connection* con, int* bytes_read);
 static int ws_conn_init(struct tcp_connection* c);
@@ -328,7 +328,7 @@ static void ws_report(int type, unsigned long long conn_id, int conn_flags,
 
 /*! \brief Finds a tcpconn & sends on it */
 static int proto_ws_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to_hu,
 		unsigned int id)
 {
 	struct tcp_connection *c;
@@ -337,6 +337,7 @@ static int proto_ws_send(struct socket_info* send_sock,
 	struct ip_addr ip;
 	struct ws_data* d;
 	int port = 0, fd, n, matched;
+	const union sockaddr_union *to = to_hu ? &to_hu->su : NULL;
 
 	matched = tcp_con_get_profile(to, &send_sock->su, send_sock->proto, &prof);
 
@@ -373,7 +374,7 @@ static int proto_ws_send(struct socket_info* send_sock,
 		}
 		LM_DBG("no open tcp connection found, opening new one\n");
 		/* create tcp connection */
-		if ((c=ws_connect(send_sock, to, &prof, &fd))==0) {
+		if ((c=ws_connect(send_sock, to_hu, &prof, &fd))==0) {
 			LM_ERR("connect failed\n");
 			return -1;
 		}
diff --git a/modules/proto_ws/ws_common.h b/modules/proto_ws/ws_common.h
index 201e0ccb7e8..78e155c3ebb 100644
--- a/modules/proto_ws/ws_common.h
+++ b/modules/proto_ws/ws_common.h
@@ -636,12 +636,13 @@ static void ws_close(struct tcp_connection *c)
 }
 
 static struct tcp_connection* ws_sync_connect(struct socket_info* send_sock,
-		union sockaddr_union* server, struct tcp_conn_profile *prof)
+		const struct sockaddr_hu* server_hu, struct tcp_conn_profile *prof)
 {
 	int s;
 	union sockaddr_union my_name;
 	socklen_t my_name_len;
 	struct tcp_connection* con;
+	const union sockaddr_union *server = &server_hu->su;
 
 	s=socket(AF2PF(server->s.sa_family), SOCK_STREAM, 0);
 	if (s==-1){
@@ -667,7 +668,7 @@ static struct tcp_connection* ws_sync_connect(struct socket_info* send_sock,
 		LM_ERR("tcp_blocking_connect failed\n");
 		goto error;
 	}
-	con=tcp_conn_create(s, server, send_sock, prof, S_CONN_OK, 0);
+	con=tcp_conn_create(s, server_hu, send_sock, prof, S_CONN_OK, 0);
 	if (con==NULL){
 		LM_ERR("tcp_conn_create failed, closing the socket\n");
 		goto error;
@@ -684,7 +685,7 @@ static struct tcp_connection* ws_sync_connect(struct socket_info* send_sock,
 
 
 static struct tcp_connection* ws_connect(struct socket_info* send_sock,
-		union sockaddr_union* to, struct tcp_conn_profile *prof, int *fd)
+		const struct sockaddr_hu* to, struct tcp_conn_profile *prof, int *fd)
 {
 	struct tcp_connection *c;
 
diff --git a/modules/rtpproxy/rtpproxy.c b/modules/rtpproxy/rtpproxy.c
index 371a345a4d6..ecea761dd01 100644
--- a/modules/rtpproxy/rtpproxy.c
+++ b/modules/rtpproxy/rtpproxy.c
@@ -3287,7 +3287,7 @@ force_rtpproxy_body_part(struct sip_msg *msg, struct rtpp_args *args,
 {
 	int ret = 0;
 	struct rtpp_args *ap;
-	union sockaddr_union to;
+	struct sockaddr_hu to;
 	struct ip_addr ip;
 	struct cell *trans;
 
@@ -3349,7 +3349,7 @@ force_rtpproxy_body_part(struct sip_msg *msg, struct rtpp_args *args,
 				} else if (parse_headers(msg, HDR_VIA2_F, 0) != -1 &&
 				(msg->via2 != NULL) && (msg->via2->error == PARSE_OK) &&
 				update_sock_struct_from_via(&to, msg, msg->via2)!=-1) {
-					su2ip_addr(&ip, &to);
+					su2ip_addr(&ip, &to.su);
 					args->raddr.s = ip_addr2a(&ip);
 					args->raddr.len = strlen(args->raddr.s);
 				} else {
diff --git a/modules/sipcapture/sipcapture.c b/modules/sipcapture/sipcapture.c
index a07f26e7a6f..029f6e5f786 100644
--- a/modules/sipcapture/sipcapture.c
+++ b/modules/sipcapture/sipcapture.c
@@ -4252,7 +4252,7 @@ static int w_hep_relay(struct sip_msg *msg)
 
 	struct socket_info* send_sock;
 
-	union sockaddr_union to;
+	struct sockaddr_hu to;
 
 	str* uri_s;
 	str  buf_s;
@@ -4316,14 +4316,14 @@ static int w_hep_relay(struct sip_msg *msg)
 		return 0;
 	}
 
-	hostent2su( &to, &proxy->host, proxy->addr_idx,
+	hostent2hu( &to, &proxy->host, proxy->addr_idx,
 				(proxy->port)?proxy->port:SIP_PORT);
 
 	/* FIXME */
-	send_sock=get_send_socket(0, &to, hep_proto);
+	send_sock=get_send_socket(0, &to.su, hep_proto);
 	if (send_sock==0){
 		LM_ERR("cannot forward to af %d, proto %d no corresponding"
-			"listening socket\n", to.s.sa_family, proxy->proto);
+			"listening socket\n", to.su.s.sa_family, proxy->proto);
 		return -1;
 	}
 
@@ -4334,7 +4334,7 @@ static int w_hep_relay(struct sip_msg *msg)
 		}
 
 		break;
-	} while( get_next_su( proxy, &to, 0)==0 );
+	} while( get_next_su( proxy, &to.su, 0)==0 );
 
 	free_proxy(proxy);
 	pkg_free(proxy);
diff --git a/modules/sl/sl_funcs.c b/modules/sl/sl_funcs.c
index 0b482811790..1a786c63417 100644
--- a/modules/sl/sl_funcs.c
+++ b/modules/sl/sl_funcs.c
@@ -144,7 +144,7 @@ static inline void update_sl_reply_stat(int code)
 int sl_send_reply_helper(struct sip_msg *msg ,int code, const str *text)
 {
 	str buf;
-	union sockaddr_union to;
+	struct sockaddr_hu to;
 	char *dset;
 	int dset_len;
 	struct bookmark dummy_bm;
diff --git a/modules/tcp_mgm/tcp_path.c b/modules/tcp_mgm/tcp_path.c
index 721be6b623a..712951ab77b 100644
--- a/modules/tcp_mgm/tcp_path.c
+++ b/modules/tcp_mgm/tcp_path.c
@@ -52,7 +52,7 @@ int tcp_path_init(void)
 }
 
 
-int tcp_mgm_get_profile(union sockaddr_union *remote,
+int tcp_mgm_get_profile(const union sockaddr_union *remote,
          union sockaddr_union *local, enum sip_protos proto,
          struct tcp_conn_profile *out_profile)
 {
diff --git a/modules/tcp_mgm/tcp_path.h b/modules/tcp_mgm/tcp_path.h
index ce3e215c636..ba035539aa6 100644
--- a/modules/tcp_mgm/tcp_path.h
+++ b/modules/tcp_mgm/tcp_path.h
@@ -54,7 +54,7 @@ void tcp_path_destroy(void);
 
 int tcp_store_path(int *int_vals, char **str_vals, struct tcp_path *path);
 
-int tcp_mgm_get_profile(union sockaddr_union *remote,
+int tcp_mgm_get_profile(const union sockaddr_union *remote,
          union sockaddr_union *local, enum sip_protos proto,
          struct tcp_conn_profile *out_profile);
 
diff --git a/modules/tm/dlg.h b/modules/tm/dlg.h
index 71d0531a5fd..ce35d86287a 100644
--- a/modules/tm/dlg.h
+++ b/modules/tm/dlg.h
@@ -97,7 +97,7 @@ typedef struct dlg {
 	str loc_uri;            /* Local URI */
 	str rem_uri;            /* Remote URI */
 	str obp;                /* Outbound proxy */
-	union sockaddr_union forced_to_su;	/* Forced remote sockaddr */
+	struct sockaddr_hu forced_to_hu;	/* Forced remote sockaddr */
 	str rem_target;         /* Remote target URI */
 	str loc_dname;			/* Local Display Name */
 	str rem_dname;			/* Remote Display Name */
diff --git a/modules/tm/t_funcs.c b/modules/tm/t_funcs.c
index 385f1848391..bc3b180311e 100644
--- a/modules/tm/t_funcs.c
+++ b/modules/tm/t_funcs.c
@@ -64,10 +64,10 @@ int send_pr_buffer( struct retr_buf *rb, void *buf, int len,
 #endif
 					void* ctx)
 {
-	if (buf && len && rb )
+	if (buf && len && rb ) {
 		return msg_send( rb->dst.send_sock, rb->dst.proto, &rb->dst.to,
 				         rb->dst.proto_reserved1, buf, len, ctx);
-	else {
+	} else {
 #ifdef EXTRA_DEBUG
 		LM_CRIT("sending an empty buffer from %s: %s (%d)\n",file,
 				function, line);
diff --git a/modules/tm/t_fwd.c b/modules/tm/t_fwd.c
index 6d9029a7d68..81ef1456826 100644
--- a/modules/tm/t_fwd.c
+++ b/modules/tm/t_fwd.c
@@ -329,12 +329,12 @@ static inline int update_uac_dst( struct sip_msg *request,
 	char *shbuf;
 	unsigned int len;
 
-	send_sock = get_send_socket( request, &uac->request.dst.to ,
+	send_sock = get_send_socket( request, &uac->request.dst.to.su ,
 			uac->request.dst.proto );
 	if (send_sock==0) {
 		LM_ERR("failed to fwd to af %d, proto %d "
 			" (no corresponding listening socket)\n",
-			uac->request.dst.to.s.sa_family, uac->request.dst.proto );
+			uac->request.dst.to.su.s.sa_family, uac->request.dst.proto );
 		ser_error=E_NO_SOCKET;
 		return -1;
 	}
@@ -455,7 +455,7 @@ static int add_uac( struct cell *t, struct sip_msg *request, const str *uri,
 	}
 
 	/* use the first address */
-	hostent2su( &t->uac[branch].request.dst.to,
+	hostent2hu( &t->uac[branch].request.dst.to,
 		&proxy->host, proxy->addr_idx, proxy->port ? proxy->port:SIP_PORT);
 	t->uac[branch].request.dst.proto = proxy->proto;
 
@@ -747,7 +747,7 @@ int t_forward_nonack( struct cell *t, struct sip_msg* p_msg ,
 
 	/* check if the UAS retranmission port needs to be updated */
 	if ( (p_msg->msg_flags ^ t->uas.request->msg_flags) & FL_FORCE_RPORT )
-		su_setport( &t->uas.response.dst.to, p_msg->rcv.src_port );
+		su_setport( &t->uas.response.dst.to.su, p_msg->rcv.src_port );
 
 	/* if no more specific error code is known, use this */
 	lowest_ret=E_BUG;
@@ -832,7 +832,7 @@ int t_forward_nonack( struct cell *t, struct sip_msg* p_msg ,
 
 			do {
 				if (check_blacklists( t->uac[i].request.dst.proto,
-				&t->uac[i].request.dst.to,
+				&t->uac[i].request.dst.to.su,
 				t->uac[i].request.buffer.s,
 				t->uac[i].request.buffer.len)) {
 					LM_DBG("blocked by blacklists\n");
@@ -855,7 +855,7 @@ int t_forward_nonack( struct cell *t, struct sip_msg* p_msg ,
 				}
 				/* get next dns entry */
 				if ( t->uac[i].proxy==0 ||
-				get_next_su( t->uac[i].proxy, &t->uac[i].request.dst.to,
+				get_next_su( t->uac[i].proxy, &t->uac[i].request.dst.to.su,
 				(ser_error==E_IP_BLOCKED)?0:1)!=0 )
 					break;
 				t->uac[i].request.dst.proto = t->uac[i].proxy->proto;
diff --git a/modules/tm/t_reply.c b/modules/tm/t_reply.c
index db2775ae9f8..23ddfd70323 100644
--- a/modules/tm/t_reply.c
+++ b/modules/tm/t_reply.c
@@ -520,7 +520,7 @@ static int _reply( struct cell *trans, struct sip_msg* p_msg,
 
 	/* check if the UAS retranmission port needs to be updated */
 	if ( (p_msg->msg_flags ^ trans->uas.request->msg_flags) & FL_FORCE_RPORT )
-		su_setport( &trans->uas.response.dst.to, p_msg->rcv.src_port );
+		su_setport( &trans->uas.response.dst.to.su, p_msg->rcv.src_port );
 
 	if (code>=180 && p_msg->to
 				&& (get_to(p_msg)->tag_value.s==0
@@ -681,7 +681,7 @@ static inline int do_dns_failover(struct cell *t)
 	uac = &t->uac[picked_branch];
 
 	/* check if the DNS resolver can get at least one new IP */
-	if ( get_next_su( uac->proxy, &uac->request.dst.to, 1)!=0 )
+	if ( get_next_su( uac->proxy, &uac->request.dst.to.su, 1)!=0 )
 		return -1;
 
 	LM_DBG("new destination available\n");
diff --git a/modules/tm/uac.c b/modules/tm/uac.c
index a82ee564cb1..a673ef99a8a 100644
--- a/modules/tm/uac.c
+++ b/modules/tm/uac.c
@@ -170,7 +170,7 @@ static int run_local_route( struct cell *new_cell, char **buf, int *buf_len,
 	int backup_route_type;
 	struct retr_buf *request;
 	struct proxy_l *new_proxy = NULL;
-	union sockaddr_union new_to_su;
+	struct sockaddr_hu new_to_hu;
 	struct socket_info *new_send_sock;
 	unsigned short dst_changed;
 	char *buf1=NULL, *sipmsg_buf;
@@ -235,7 +235,7 @@ static int run_local_route( struct cell *new_cell, char **buf, int *buf_len,
 			if (new_proxy==0)
 				goto skip_update;
 			/* use the first address */
-			hostent2su( &new_to_su,
+			hostent2hu( &new_to_hu,
 				&new_proxy->host, new_proxy->addr_idx,
 				new_proxy->port ? new_proxy->port:SIP_PORT);
 			/* get the send socket */
@@ -245,7 +245,7 @@ static int run_local_route( struct cell *new_cell, char **buf, int *buf_len,
 			dialog->pref_sock->proto==new_proxy->proto) {
 				new_send_sock = dialog->pref_sock;
 			} else {
-				new_send_sock = get_send_socket( req, &new_to_su,
+				new_send_sock = get_send_socket( req, &new_to_hu.su,
 					new_proxy->proto);
 				if (new_send_sock==NULL) {
 					free_proxy( new_proxy );
@@ -337,7 +337,7 @@ static int run_local_route( struct cell *new_cell, char **buf, int *buf_len,
 			request->dst.proto_reserved1 = 0;
 		}
 		if (new_proxy) {
-			request->dst.to = new_to_su;
+			hu_dup(&new_to_hu, &request->dst.to);
 			/* for DNS based failover, copy the DNS proxy into transaction */
 			if (!disable_dns_failover) {
 				new_cell->uac[0].proxy = shm_clone_proxy( new_proxy,
@@ -410,7 +410,7 @@ static int run_local_route( struct cell *new_cell, char **buf, int *buf_len,
 int t_uac(str* method, str* headers, str* body, dlg_t* dialog,
 				transaction_cb cb, void* cbp,release_tmcb_param release_func)
 {
-	union sockaddr_union to_su;
+	struct sockaddr_hu to_hu;
 	struct cell *new_cell;
 	struct retr_buf *request;
 	struct sip_msg *req = NULL;
@@ -446,7 +446,7 @@ int t_uac(str* method, str* headers, str* body, dlg_t* dialog,
 		goto error_out;
 	}
 	/* use the first address */
-	hostent2su( &to_su,
+	hostent2hu( &to_hu,
 		&proxy->host, proxy->addr_idx, proxy->port ? proxy->port:SIP_PORT);
 
 	/* check/discover the send socket */
@@ -461,11 +461,11 @@ int t_uac(str* method, str* headers, str* body, dlg_t* dialog,
 			dialog->send_sock = dialog->pref_sock;
 		} else {
 			/* get the send socket */
-			dialog->send_sock = get_send_socket(NULL/*msg*/, &to_su,
+			dialog->send_sock = get_send_socket(NULL/*msg*/, &to_hu.su,
 				proxy->proto);
 			if (!dialog->send_sock) {
 				LM_ERR("no corresponding socket for af %d\n",
-					to_su.s.sa_family);
+					to_hu.su.s.sa_family);
 				ser_error = E_NO_SOCKET;
 				goto error3;
 			}
@@ -511,10 +511,10 @@ int t_uac(str* method, str* headers, str* body, dlg_t* dialog,
 	new_cell->flags |= T_IS_LOCAL_FLAG;
 
 	request = &new_cell->uac[0].request;
-	if (dialog->forced_to_su.s.sa_family == AF_UNSPEC)
-		request->dst.to = to_su;
+	if (dialog->forced_to_hu.su.s.sa_family == AF_UNSPEC)
+		hu_dup(&to_hu, &request->dst.to);
 	else
-		request->dst.to = dialog->forced_to_su;
+		hu_dup(&dialog->forced_to_hu, &request->dst.to);
 	request->dst.send_sock = dialog->send_sock;
 	request->dst.proto = dialog->send_sock->proto;
 	request->dst.proto_reserved1 = 0;
diff --git a/modules/tracer/tracer.c b/modules/tracer/tracer.c
index b69ea870615..7af560a0d44 100644
--- a/modules/tracer/tracer.c
+++ b/modules/tracer/tracer.c
@@ -154,7 +154,7 @@ static void trace_tm_in_rev(struct cell* t, int type, struct tmcb_params *ps);
 static void trace_tm_out(struct cell* t, int type, struct tmcb_params *ps);
 static void trace_tm_out_rev(struct cell* t, int type, struct tmcb_params *ps);
 static void trace_msg_out(struct sip_msg* req, str  *buffer,
-		struct socket_info* send_sock, int proto, union sockaddr_union *to,
+		struct socket_info* send_sock, int proto, const union sockaddr_union *to,
 		trace_info_p info, int leg_flag);
 static void siptrace_dlg_cancel(struct cell* t, int type, struct tmcb_params *param);
 
@@ -163,9 +163,9 @@ static void siptrace_dlg_cancel(struct cell* t, int type, struct tmcb_params *pa
  * stateful transaction
  */
 static void trace_slreq_out(struct sip_msg* req, str *buffer,int rpl_code,
-				union sockaddr_union *to, struct socket_info *sock, int proto);
+				const struct sockaddr_hu *to, struct socket_info *sock, int proto);
 static void trace_slreply_out(struct sip_msg* req, str *buffer,int rpl_code,
-				union sockaddr_union *dst, struct socket_info *sock, int proto);
+				const struct sockaddr_hu *dst, struct socket_info *sock, int proto);
 
 #if 0
 static void trace_slack_in(struct sip_msg* req, str *buffer,int rpl_code,
@@ -1978,7 +1978,7 @@ static int sip_trace_handle(struct sip_msg *msg, tlist_elem_p el,
 			s.s = msg->buf;
 			s.len = msg->len;
 			trace_msg_out( msg, &s, msg->rcv.bind_address, msg->rcv.proto,
-				&tmb.t_gett()->uac[0].request.dst.to, info, TRACE_C_CALLEE);
+				&tmb.t_gett()->uac[0].request.dst.to.su, info, TRACE_C_CALLEE);
 		} else
 		/* otherwise trace only if per-message or not in local route
 		 * (UAC trans do not have IN msg) */
@@ -2292,7 +2292,7 @@ static void trace_onreq_out(struct cell* t, int type, struct tmcb_params *ps,
 		trace_msg_out( ps->req, (str*)ps->extra1,
 			dest->send_sock,
 			dest->proto,
-			&dest->to,
+			&dest->to.su,
 			&info,
 			leg_flag);
 	} else {
@@ -2304,9 +2304,10 @@ static void trace_onreq_out(struct cell* t, int type, struct tmcb_params *ps,
 }
 
 static void trace_slreq_out(struct sip_msg* req, str *buffer,int rpl_code,
-				union sockaddr_union *to, struct socket_info *sock, int proto)
+				const struct sockaddr_hu *to_hu, struct socket_info *sock, int proto)
 {
 	trace_info_p info;
+	const union sockaddr_union *to = to_hu ? &to_hu->su : NULL;
 
 	info = GET_TRACER_CONTEXT;
 
@@ -2317,7 +2318,7 @@ static void trace_slreq_out(struct sip_msg* req, str *buffer,int rpl_code,
 }
 
 static void trace_slreply_out(struct sip_msg* req, str *buffer,int rpl_code,
-				union sockaddr_union *dst, struct socket_info *sock, int proto)
+				const struct sockaddr_hu *dst, struct socket_info *sock, int proto)
 {
 	static char fromip_buff[IP_ADDR_MAX_STR_SIZE+12];
 	static char toip_buff[IP_ADDR_MAX_STR_SIZE+12];
@@ -2379,9 +2380,9 @@ static void trace_slreply_out(struct sip_msg* req, str *buffer,int rpl_code,
 	{
 		set_columns_to_any(db_vals[7], db_vals[8], db_vals[9]);
 	} else {
-		su2ip_addr(&to_ip, dst);
+		su2ip_addr(&to_ip, &dst->su);
 		set_sock_columns( db_vals[7], db_vals[8],db_vals[9], toip_buff, &to_ip,
-		(unsigned short)su_getport(dst), req->rcv.proto);
+		(unsigned short)su_getport(&dst->su), req->rcv.proto);
 	}
 
 	db_vals[10].val.time_val = time(NULL);
@@ -2456,7 +2457,7 @@ static int parse_from_and_callid(struct sip_msg* msg, str *from_tag) {
 }
 
 static void trace_msg_out(struct sip_msg* msg, str  *sbuf,
-		struct socket_info* send_sock, int proto, union sockaddr_union *to,
+		struct socket_info* send_sock, int proto, const union sockaddr_union *to,
 		trace_info_p info, int leg_flag)
 {
 	static char fromip_buff[IP_ADDR_MAX_STR_SIZE+12];
@@ -2818,11 +2819,11 @@ static void trace_onreply_out(struct cell* t, int type, struct tmcb_params *ps,
 		set_columns_to_any( db_vals[7], db_vals[8], db_vals[9]);
 	} else {
 		memset(&to_ip, 0, sizeof(struct ip_addr));
-		su2ip_addr(&to_ip, &dst->to);
+		su2ip_addr(&to_ip, &dst->to.su);
 		set_sock_columns( db_vals[7], db_vals[8], db_vals[9], toip_buff,
 			&to_ip,
 			(unsigned long)(dst->send_sock && dst->send_sock->last_remote_real_port?
-				dst->send_sock->last_remote_real_port:su_getport(&dst->to)),
+				dst->send_sock->last_remote_real_port:su_getport(&dst->to.su)),
 			dst->proto);
 	}
 
@@ -3422,7 +3423,7 @@ static mi_response_t *sip_trace_mi_2(const mi_params_t *params,
 
 static int trace_send_duplicate(char *buf, int len, struct sip_uri *uri)
 {
-	union sockaddr_union* to;
+	struct sockaddr_hu* to;
 	struct socket_info* send_sock;
 	struct proxy_l * p;
 	int proto;
@@ -3434,7 +3435,7 @@ static int trace_send_duplicate(char *buf, int len, struct sip_uri *uri)
 	if(uri==NULL)
 		return 0;
 
-	to=(union sockaddr_union*)pkg_malloc(sizeof(union sockaddr_union));
+	to=(struct sockaddr_hu*)pkg_malloc(sizeof(*to));
 	if (to==0){
 		LM_ERR("out of pkg memory\n");
 		return -1;
@@ -3450,16 +3451,16 @@ static int trace_send_duplicate(char *buf, int len, struct sip_uri *uri)
 		return -1;
 	}
 
-	hostent2su(to, &p->host, p->addr_idx,
+	hostent2hu(to, &p->host, p->addr_idx,
 				(p->port)?p->port:SIP_PORT);
 
 	ret = -1;
 
 	do {
-		send_sock=get_send_socket(0, to, proto);
+		send_sock=get_send_socket(0, &to->su, proto);
 		if (send_sock==0){
 			LM_ERR("can't forward to af %d, proto %d no corresponding listening socket\n",
-					to->s.sa_family,proto);
+					to->su.s.sa_family,proto);
 			continue;
 		}
 
@@ -3469,7 +3470,7 @@ static int trace_send_duplicate(char *buf, int len, struct sip_uri *uri)
 		}
 		ret = 0;
 		break;
-	}while( get_next_su( p, to, 0)==0 );
+	}while( get_next_su( p, &to->su, 0)==0 );
 
 	free_proxy(p); /* frees only p content, not p itself */
 	pkg_free(p);
diff --git a/modules/uac_registrant/registrant.c b/modules/uac_registrant/registrant.c
index b12339c9d94..3ff82fb61be 100644
--- a/modules/uac_registrant/registrant.c
+++ b/modules/uac_registrant/registrant.c
@@ -383,9 +383,9 @@ int run_reg_tm_cback(void *e_data, void *data, void *r_data)
 	reg_print_record(rec);
 
 	if (ps->rpl==FAKED_REPLY)
-		memset(&rec->td.forced_to_su, 0, sizeof(union sockaddr_union));
-	else if (rec->td.forced_to_su.s.sa_family == AF_UNSPEC)
-		rec->td.forced_to_su = t->uac[0].request.dst.to;
+		memset(&rec->td.forced_to_hu, 0, sizeof(rec->td.forced_to_hu));
+	else if (rec->td.forced_to_hu.su.s.sa_family == AF_UNSPEC)
+		hu_dup(&t->uac[0].request.dst.to, &rec->td.forced_to_hu);
 
 	statuscode = ps->code;
 	switch(statuscode) {
@@ -1130,15 +1130,15 @@ int run_mi_reg_list(void *e_data, void *data, void *r_data)
 			rec->td.obp.s, rec->td.obp.len) < 0)
 			goto error;
 
-	switch(rec->td.forced_to_su.s.sa_family) {
+	switch(rec->td.forced_to_hu.su.s.sa_family) {
 	case AF_UNSPEC:
 		break;
 	case AF_INET:
 	case AF_INET6:
 		if (add_mi_string(record_item, MI_SSTR("dst_IP"),
-			(rec->td.forced_to_su.s.sa_family==AF_INET)?"IPv4":"IPv6", 4) < 0)
+			(rec->td.forced_to_hu.su.s.sa_family==AF_INET)?"IPv4":"IPv6", 4) < 0)
 			goto error;
-		sockaddr2ip_addr(&addr, &rec->td.forced_to_su.s);
+		sockaddr2ip_addr(&addr, &rec->td.forced_to_hu.su.s);
 		p = ip_addr2a(&addr);
 		if (p == NULL) goto error;
 		len = strlen(p);
@@ -1146,12 +1146,12 @@ int run_mi_reg_list(void *e_data, void *data, void *r_data)
 			goto error;
 		break;
 	default:
-		LM_ERR("unexpected sa_family [%d]\n", rec->td.forced_to_su.s.sa_family);
+		LM_ERR("unexpected sa_family [%d]\n", rec->td.forced_to_hu.su.s.sa_family);
 		if (add_mi_string(record_item, MI_SSTR("dst_IP"), "Error", 5) < 0)
 			goto error;
 
 		if (add_mi_number(record_item, MI_SSTR("sa_family"),
-			rec->td.forced_to_su.s.sa_family) < 0)
+			rec->td.forced_to_hu.su.s.sa_family) < 0)
 			goto error;
 	}
 
diff --git a/net/api_proto.h b/net/api_proto.h
index 39f708f2a2d..5efbcbf9818 100644
--- a/net/api_proto.h
+++ b/net/api_proto.h
@@ -32,7 +32,7 @@
 
 typedef int (*proto_init_listener_f)(struct socket_info *si);
 typedef int (*proto_send_f)(struct socket_info *si, char* buf,unsigned int len,
-		union sockaddr_union* to, int unsigned id);
+		const struct sockaddr_hu* to, int unsigned id);
 typedef int (*proto_dst_attr_f)(struct receive_info *rcv,
 		int attr, void *value);
 
diff --git a/net/net_tcp.c b/net/net_tcp.c
index aa3b3667383..0b71e9262e3 100644
--- a/net/net_tcp.c
+++ b/net/net_tcp.c
@@ -864,7 +864,7 @@ static inline void tcpconn_ref(struct tcp_connection* c)
 }
 
 
-static struct tcp_connection* tcpconn_new(int sock, union sockaddr_union* su,
+static struct tcp_connection* tcpconn_new(int sock, const union sockaddr_union* su,
                     struct socket_info* si, struct tcp_conn_profile *prof,
                     int state, int flags)
 {
@@ -951,12 +951,21 @@ static struct tcp_connection* tcpconn_new(int sock, union sockaddr_union* su,
  * IMPORTANT - the function assumes you want to create a new TCP conn as
  * a result of a connect operation - the conn will be set as connect !!
  * Accepted connection are triggered internally only */
-struct tcp_connection* tcp_conn_create(int sock, union sockaddr_union* su,
+struct tcp_connection* tcp_conn_create(int sock, const struct sockaddr_hu* shu,
 		struct socket_info* si, struct tcp_conn_profile *prof,
 		int state, int send2main)
 {
 	struct tcp_connection *c;
+	const union sockaddr_union *su = &shu->su;
 
+	if (shu->hp == NULL) {
+		LM_ERR("tcpconn_new: no hostinfo");
+		return NULL;
+	}
+	if (shu->hp->len >= sizeof(c->hostname)) {
+		LM_ERR("tcpconn_new: host name is too long %d", shu->hp->len);
+		return NULL;
+	}
 	if (!prof)
 		tcp_con_get_profile(su, &si->su, si->proto, prof);
 
@@ -969,8 +978,8 @@ struct tcp_connection* tcp_conn_create(int sock, union sockaddr_union* su,
 
 	/* copy peer hostname into the tcp_connection so that tls_openssl can verify
 	 * the certificate hostname */
-	strncpy(c->hostname, su->h.hostname, sizeof(c->hostname)-1);
-	c->hostname[sizeof(c->hostname)-1] = 0;
+	memcpy(c->hostname, shu->hp->s, shu->hp->len);
+	c->hostname[shu->hp->len] = 0;
 
 	if (protos[c->type].net.conn_init &&
 			protos[c->type].net.conn_init(c) < 0) {
diff --git a/net/net_tcp.h b/net/net_tcp.h
index f99d34c1f99..0c2d137918d 100644
--- a/net/net_tcp.h
+++ b/net/net_tcp.h
@@ -90,7 +90,7 @@ int tcp_conn_get(int unsigned id, struct ip_addr* ip, int port,
 		struct socket_info* send_sock);
 
 /* creates a new tcp conn around a newly connected socket */
-struct tcp_connection* tcp_conn_create(int sock, union sockaddr_union* su,
+struct tcp_connection* tcp_conn_create(int sock, const struct sockaddr_hu *su,
 		struct socket_info* si, struct tcp_conn_profile *prof,
 		int state, int send2main);
 
diff --git a/net/proto_tcp/proto_tcp.c b/net/proto_tcp/proto_tcp.c
index ce4e67263c4..131159a32a4 100644
--- a/net/proto_tcp/proto_tcp.c
+++ b/net/proto_tcp/proto_tcp.c
@@ -53,7 +53,7 @@ static int mod_init(void);
 static int proto_tcp_init(struct proto_info *pi);
 static int proto_tcp_init_listener(struct socket_info *si);
 static int proto_tcp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 inline static int _tcp_write_on_socket(struct tcp_connection *c, int fd,
 		char *buf, int len);
@@ -362,7 +362,7 @@ inline static int _tcp_write_on_socket(struct tcp_connection *c, int fd,
 /*! \brief Finds a tcpconn & sends on it */
 static int proto_tcp_send(struct socket_info* send_sock,
 									char* buf, unsigned int len,
-									union sockaddr_union* to, unsigned int id)
+									const struct sockaddr_hu* to_hu, unsigned int id)
 {
 	struct tcp_connection *c;
 	struct tcp_conn_profile prof;
@@ -370,6 +370,7 @@ static int proto_tcp_send(struct socket_info* send_sock,
 	struct timeval get,snd;
 	union sockaddr_union src_su, dst_su;
 	int port = 0, fd, n, matched;
+	const union sockaddr_union *to = (to_hu != NULL) ? &to_hu->su : NULL;
 
 	matched = tcp_con_get_profile(to, &send_sock->su, send_sock->proto, &prof);
 
@@ -408,7 +409,7 @@ static int proto_tcp_send(struct socket_info* send_sock,
 			tcp_async);
 		/* create tcp connection */
 		if (tcp_async) {
-			n = tcp_async_connect(send_sock, to, &prof,
+			n = tcp_async_connect(send_sock, to_hu, &prof,
 					tcp_async_local_connect_timeout, &c, &fd, 1);
 			if ( n<0 ) {
 				LM_ERR("async TCP connect failed\n");
@@ -470,7 +471,7 @@ static int proto_tcp_send(struct socket_info* send_sock,
 				}
 			}
 		} else {
-			if ((c=tcp_sync_connect(send_sock, to, &prof, &fd, 1))==0) {
+			if ((c=tcp_sync_connect(send_sock, to_hu, &prof, &fd, 1))==0) {
 				LM_ERR("connect failed\n");
 				get_time_difference(get,prof.send_threshold,tcp_timeout_con_get);
 				return -1;
diff --git a/net/proto_udp/proto_udp.c b/net/proto_udp/proto_udp.c
index bc7ed56d4ed..662c64b42a9 100644
--- a/net/proto_udp/proto_udp.c
+++ b/net/proto_udp/proto_udp.c
@@ -44,7 +44,7 @@ static int mod_init(void);
 static int proto_udp_init(struct proto_info *pi);
 static int proto_udp_init_listener(struct socket_info *si);
 static int proto_udp_send(struct socket_info* send_sock,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to,
 		unsigned int id);
 
 static int udp_read_req(struct socket_info *src, int* bytes_read);
@@ -199,10 +199,11 @@ static int udp_read_req(struct socket_info *si, int* bytes_read)
  * \return -1 on error, the return value from sento on success
  */
 static int proto_udp_send(struct socket_info* source,
-		char* buf, unsigned int len, union sockaddr_union* to,
+		char* buf, unsigned int len, const struct sockaddr_hu* to_hu,
 		unsigned int id)
 {
 	int n, tolen;
+	const union sockaddr_union *to = &to_hu->su;
 
 	tolen=sockaddru_len(*to);
 again:
diff --git a/net/tcp_common.c b/net/tcp_common.c
index 76ffeec1c30..ed3a4f87997 100644
--- a/net/tcp_common.c
+++ b/net/tcp_common.c
@@ -140,12 +140,13 @@ int tcp_connect_blocking(int fd, const struct sockaddr *servaddr,
 			tcp_connect_timeout);
 }
 
-int tcp_sync_connect_fd(union sockaddr_union* src, union sockaddr_union* dst,
+int tcp_sync_connect_fd(union sockaddr_union* src,  const struct sockaddr_hu* hup,
                  enum sip_protos proto, struct tcp_conn_profile *prof, enum si_flags flags)
 {
 	int s;
 	union sockaddr_union my_name;
 	socklen_t my_name_len;
+	const union sockaddr_union *dst = &hup->su;
 
 	s=socket(AF2PF(dst->s.sa_family), SOCK_STREAM, 0);
 	if (s==-1){
@@ -182,7 +183,7 @@ int tcp_sync_connect_fd(union sockaddr_union* src, union sockaddr_union* dst,
 }
 
 struct tcp_connection* tcp_sync_connect(struct socket_info* send_sock,
-               union sockaddr_union* server, struct tcp_conn_profile *prof,
+               const struct sockaddr_hu * server, struct tcp_conn_profile *prof,
                int *fd, int send2main)
 {
 	struct tcp_connection* con;
@@ -203,10 +204,11 @@ struct tcp_connection* tcp_sync_connect(struct socket_info* send_sock,
 }
 
 int tcp_async_connect(struct socket_info* send_sock,
-            union sockaddr_union* server, struct tcp_conn_profile *prof,
+            const struct sockaddr_hu* hsu, struct tcp_conn_profile *prof,
             int timeout, struct tcp_connection** c, int *ret_fd, int send2main)
 {
 	int fd, n;
+	const union sockaddr_union *server = &hsu->su;
 	union sockaddr_union my_name;
 	socklen_t my_name_len;
 	struct tcp_connection* con;
@@ -330,7 +332,7 @@ int tcp_async_connect(struct socket_info* send_sock,
 async_connect:
 	LM_DBG("Create connection for async connect\n");
 	/* create a new dummy connection */
-	con=tcp_conn_create(fd, server, send_sock,
+	con=tcp_conn_create(fd, hsu, send_sock,
 	                    prof, S_CONN_CONNECTING, send2main);
 	if (con==NULL) {
 		LM_ERR("tcp_conn_create failed\n");
@@ -341,7 +343,7 @@ int tcp_async_connect(struct socket_info* send_sock,
 	return 0;
 
 local_connect:
-	con=tcp_conn_create(fd, server, send_sock, prof, S_CONN_OK, send2main);
+	con=tcp_conn_create(fd, hsu, send_sock, prof, S_CONN_OK, send2main);
 	if (con==NULL) {
 		LM_ERR("tcp_conn_create failed, closing the socket\n");
 		goto error;
diff --git a/net/tcp_common.h b/net/tcp_common.h
index 5d95b2c5e94..426f97ef4d6 100644
--- a/net/tcp_common.h
+++ b/net/tcp_common.h
@@ -30,11 +30,11 @@ int tcp_connect_blocking_timeout(int fd, const struct sockaddr *servaddr,
                         socklen_t addrlen, int timeout_ms);
 
 
-int tcp_sync_connect_fd(union sockaddr_union* src, union sockaddr_union* dst,
+int tcp_sync_connect_fd(union sockaddr_union* src, const struct sockaddr_hu* dst,
                  enum sip_protos proto, struct tcp_conn_profile *prof, enum si_flags flags);
 
 struct tcp_connection* tcp_sync_connect(struct socket_info* send_sock,
-               union sockaddr_union* server, struct tcp_conn_profile *prof,
+               const struct sockaddr_hu* server, struct tcp_conn_profile *prof,
                int *fd, int send2main);
 
 /* Attempts do a connect to the given destination. It returns:
@@ -43,7 +43,7 @@ struct tcp_connection* tcp_sync_connect(struct socket_info* send_sock,
  *  -1 - error
  */
 int tcp_async_connect(struct socket_info* send_sock,
-           union sockaddr_union* server, struct tcp_conn_profile *prof,
+           const struct sockaddr_hu* server, struct tcp_conn_profile *prof,
            int timeout, struct tcp_connection** c, int *ret_fd, int send2main);
 
 /* Responsible for writing the TCP send chunks - called under con write lock
diff --git a/net/tcp_conn_profile.c b/net/tcp_conn_profile.c
index d9990fd8726..505033ba40c 100644
--- a/net/tcp_conn_profile.c
+++ b/net/tcp_conn_profile.c
@@ -26,7 +26,7 @@
  * by defining specific settings (per TCP path) using the "tcp_mgm" module */
 struct tcp_conn_profile tcp_con_df_profile;
 
-static int tcp_con_get_df_profile(union sockaddr_union *_,
+static int tcp_con_get_df_profile(const union sockaddr_union *_,
         union sockaddr_union *__, enum sip_protos ___,
         struct tcp_conn_profile *out_profile)
 {
@@ -36,7 +36,7 @@ static int tcp_con_get_df_profile(union sockaddr_union *_,
 
 
 /* global function/variable which may be overridden by tcp_mgm */
-int (*tcp_con_get_profile)(union sockaddr_union *remote,
+int (*tcp_con_get_profile)(const union sockaddr_union *remote,
          union sockaddr_union *local, enum sip_protos proto,
          struct tcp_conn_profile *out_profile) = tcp_con_get_df_profile;
 
diff --git a/net/tcp_conn_profile.h b/net/tcp_conn_profile.h
index 3061e12e352..eebddeaa289 100644
--- a/net/tcp_conn_profile.h
+++ b/net/tcp_conn_profile.h
@@ -44,7 +44,7 @@ enum tcp_conn_attr {
  *   0 (success, but just the default TCP profile was returned)
  *   1 (success, a custom TCP profile from tcp_mgm DB was matched)
  */
-extern int (*tcp_con_get_profile)(union sockaddr_union *remote,
+extern int (*tcp_con_get_profile)(const union sockaddr_union *remote,
              union sockaddr_union *local, enum sip_protos proto,
              struct tcp_conn_profile *out_profile);
 
diff --git a/resolve.h b/resolve.h
index 1c7babcebc8..3e0f0346585 100644
--- a/resolve.h
+++ b/resolve.h
@@ -54,8 +54,7 @@
 #define MAX_QUERY_SIZE 8192
 #define ANS_SIZE       8192
 #define DNS_HDR_SIZE     12
-#define MAX_DNS_NAME 256
-#define MAX_DNS_STRING 255
+#define MAX_DNS_STRING (MAX_DNS_NAME-1)
 
 /*! \brief this is not official yet */
 #define T_EBL		65300
diff --git a/sl_cb.c b/sl_cb.c
index 7c91e27fbdf..64cf02452d8 100644
--- a/sl_cb.c
+++ b/sl_cb.c
@@ -75,7 +75,7 @@ int register_slcb(enum sl_cb_type type, unsigned int fmask, sl_cb_t f)
 
 
 void slcb_run_reply_out(struct sip_msg *req, str *buffer,
-									union sockaddr_union *dst, int rpl_code)
+									const struct sockaddr_hu *dst, int rpl_code)
 {
 	struct sl_callback *cbp;
 
@@ -100,7 +100,7 @@ void slcb_run_ack_in(struct sip_msg *req)
 
 
 void slcb_run_req_out(struct sip_msg *req, str *buffer,
-			union sockaddr_union *dst, struct socket_info *sock, int proto)
+			const struct sockaddr_hu *dst, struct socket_info *sock, int proto)
 {
 	struct sl_callback *cbp;
 
diff --git a/sl_cb.h b/sl_cb.h
index 27005d48246..bc9e9ec658a 100644
--- a/sl_cb.h
+++ b/sl_cb.h
@@ -36,7 +36,7 @@ enum sl_cb_type {SLCB_REPLY_OUT=0, SLCB_ACK_IN, SLCB_REQUEST_OUT,
 
 /* callback function prototype */
 typedef void (sl_cb_t) (struct sip_msg* req, str *buffer, int rpl_code,
-		union sockaddr_union *dst, struct socket_info *sock, int proto);
+		const struct sockaddr_hu *dst, struct socket_info *sock, int proto);
 
 /* register callback function prototype */
 typedef int (*register_slcb_t)(enum sl_cb_type, unsigned int fmask, sl_cb_t f);
@@ -51,10 +51,10 @@ int register_slcb(enum sl_cb_type, unsigned int fmask, sl_cb_t f);
 
 /* run SL callbacks for a given type */
 void slcb_run_reply_out(struct sip_msg *req, str *buffer,
-		union sockaddr_union *dst, int rpl_code);
+		const struct sockaddr_hu *dst, int rpl_code);
 void slcb_run_ack_in(struct sip_msg *req);
 void slcb_run_req_out(struct sip_msg *req, str *buffer,
-		union sockaddr_union *dst, struct socket_info *sock, int proto);
+		const struct sockaddr_hu *dst, struct socket_info *sock, int proto);
 
 #endif