udp_server.c
e60a9728
 /*
  * $Id$
7dd0b342
  *
53c7e0f1
  * Copyright (C) 2001-2003 FhG Fokus
7dd0b342
  *
  * This file is part of ser, a free SIP server.
  *
  * ser is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version
  *
  * For a license to use the ser software under conditions
  * other than those described here, or to purchase support for this
  * software, please contact iptel.org by e-mail at the following addresses:
  *    info@iptel.org
  *
  * ser is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License 
  * along with this program; if not, write to the Free Software 
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
049f64c2
  *
  * History
  * --------
e3dccdc9
  *  2003-01-28  packet zero-termination moved to receive_msg (jiri)
  *  2003-02-10  undoed the above changes (andrei)
  *  2003-03-19  replaced all the mallocs/frees w/ pkg_malloc/pkg_free (andrei)
39546e5f
  *  2003-04-14  set sockopts to TOS low delay (andrei)
956d111a
  *  2004-05-03  applied multicast support patch from janakj
  *              added set multicast ttl support (andrei)
5260ef32
  *  2004-07-05  udp_rcv_loop: drop packets with 0 src port + error msg.
  *              cleanups (andrei)
e6b442bd
  *  2005-03-10  multicast options are now set for all the udp sockets (andrei)
741a9937
  *  2005-06-26  failure to set mcast options is not an error anymore (andrei)
e6a2b12e
  *  2006-04-12  udp_send() switched to struct dest_info (andrei)
96227c65
  *  2006-10-13  added STUN support (vlada)
f3a26797
  *  2007-08-28  disable/set MTU discover option for the udp sockets
  *               (in linux it's enabled by default which produces udp packets
  *                with the DF flag ser) (patch from hscholz)
e60a9728
  */
 
7dd0b342
 
1d0661db
 /*!
  * \file
  * \brief SIP-router core :: 
  * \ingroup core
  * Module: \ref core
  */
 
3e429f5c
 #include <stdlib.h>
 #include <string.h>
e60a9728
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
1f2c924e
 #include <netinet/in_systm.h>
39546e5f
 #include <netinet/ip.h>
e60a9728
 #include <errno.h>
68a3fc65
 #include <arpa/inet.h>
853c176f
 #ifdef __linux__
 	#include <linux/types.h>
 	#include <linux/errqueue.h>
 #endif
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 #include "udp_server.h"
4e2fdd79
 #include "globals.h"
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 #include "config.h"
 #include "dprint.h"
3e429f5c
 #include "receive.h"
dda9dab1
 #include "mem/mem.h"
4e2fdd79
 #include "ip_addr.h"
9188021a
 #include "cfg/cfg_struct.h"
e60a9728
 
96227c65
 #ifdef USE_STUN
   #include "ser_stun.h"
 #endif
e60a9728
 
c0656aad
 #ifdef DBG_MSG_QA
 /* message quality assurance -- frequently, bugs in ser have
    been indicated by zero characters or long whitespaces
    in generated messages; this debugging option aborts if
    any such message is sighted
 */
 static int dbg_msg_qa(char *buf, int len)
 {
 #define _DBG_WS_LEN 3
 #define _DBG_WS "   "
 
 	char *scan;
 	int my_len;
 	int space_cnt;
 	enum { QA_ANY, QA_SPACE, QA_EOL1 } state;
 
 
53c7e0f1
 	/* is there a zero character in there ? */	
c0656aad
 	if (memchr(buf, 0, len)) {
a57bedca
 		LOG(L_CRIT, "BUG: message with 0 in it\n");
c0656aad
 		return 0;
 	}
 
 	my_len=len;
 	scan=buf;
 	state=QA_ANY;
 	space_cnt=0;
 
 	while(my_len) {
 		switch(*scan) {
 			case ' ':	if (state==QA_SPACE) {
 							space_cnt++;
 							if (space_cnt==4) {
53c7e0f1
 								LOG(L_CRIT, "BUG(probably): DBG_MSG_QA: "
c0656aad
 									"too many spaces\n");
 								return 0;
 							}
 						} else space_cnt=0;
 						state=QA_SPACE; 
 						break;
 
 			case '\r':	/* ignore */
 						space_cnt=0;
 						break;
 
 			case '\n': /* don't proceed to body on EoH */
 						if (state==QA_EOL1) goto qa_passed;
 						space_cnt=0;
 						state=QA_EOL1;
 						break;
 
 			default:	space_cnt=0;
 						state=QA_ANY;
 						break;
 		}
 		scan++;
 		my_len--;
 	}
 
 
 qa_passed:
 	return 1;
 }
 
 #endif
 
e60a9728
 
8eddd6f6
 int probe_max_receive_buffer( int udp_sock )
e60a9728
 {
e22bbdb8
 	int optval;
9c61e9f9
 	int ioptval;
 	unsigned int ioptvallen;
 	int foptval;
 	unsigned int foptvallen;
 	int voptval;
 	unsigned int voptvallen;
d24a2059
 	int phase=0;
 
 	/* jku: try to increase buffer size as much as we can */
 	ioptvallen=sizeof(ioptval);
 	if (getsockopt( udp_sock, SOL_SOCKET, SO_RCVBUF, (void*) &ioptval,
 		    &ioptvallen) == -1 )
 	{
 		LOG(L_ERR, "ERROR: udp_init: getsockopt: %s\n", strerror(errno));
8eddd6f6
 		return -1;
d24a2059
 	}
 	if ( ioptval==0 ) 
 	{
53c7e0f1
 		LOG(L_DBG, "DEBUG: udp_init: SO_RCVBUF initially set to 0; resetting to %d\n",
d24a2059
 			BUFFER_INCREMENT );
 		ioptval=BUFFER_INCREMENT;
 	} else LOG(L_INFO, "INFO: udp_init: SO_RCVBUF is initially %d\n", ioptval );
53af8794
 	for (optval=ioptval; ;  ) {
d24a2059
 		/* increase size; double in initial phase, add linearly later */
 		if (phase==0) optval <<= 1; else optval+=BUFFER_INCREMENT;
e22bbdb8
 		if (optval > maxbuffer){
 			if (phase==1) break; 
e0a6ffa6
 			else { phase=1; optval >>=1; continue; }
 		}
d24a2059
 		LOG(L_DBG, "DEBUG: udp_init: trying SO_RCVBUF: %d\n", optval );
e22bbdb8
 		if (setsockopt( udp_sock, SOL_SOCKET, SO_RCVBUF,
 			(void*)&optval, sizeof(optval)) ==-1){
af6fb476
 			/* Solaris returns -1 if asked size too big; Linux ignores */
e22bbdb8
 			LOG(L_DBG, "DEBUG: udp_init: SOL_SOCKET failed"
 					" for %d, phase %d: %s\n", optval, phase, strerror(errno));
d24a2059
 			/* if setting buffer size failed and still in the aggressive
53c7e0f1
 			   phase, try less aggressively; otherwise give up 
d24a2059
 			*/
 			if (phase==0) { phase=1; optval >>=1 ; continue; } 
 			else break;
e22bbdb8
 		} 
d24a2059
 		/* verify if change has taken effect */
af6fb476
 		/* Linux note -- otherwise I would never know that; funny thing: Linux
 		   doubles size for which we asked in setsockopt
 		*/
d24a2059
 		voptvallen=sizeof(voptval);
 		if (getsockopt( udp_sock, SOL_SOCKET, SO_RCVBUF, (void*) &voptval,
 		    &voptvallen) == -1 )
 		{
 			LOG(L_ERR, "ERROR: udp_init: getsockopt: %s\n", strerror(errno));
8eddd6f6
 			return -1;
d24a2059
 		} else {
 			LOG(L_DBG, "DEBUG: setting SO_RCVBUF; set=%d,verify=%d\n", 
 				optval, voptval);
 			if (voptval<optval) {
 				LOG(L_DBG, "DEBUG: setting SO_RCVBUF has no effect\n");
 				/* if setting buffer size failed and still in the aggressive
53c7e0f1
 				phase, try less aggressively; otherwise give up 
d24a2059
 				*/
e22bbdb8
 				if (phase==0) { phase=1; optval >>=1 ; continue; } 
 				else break;
8eddd6f6
 			} 
d24a2059
 		}
e22bbdb8
 	
d24a2059
 	} /* for ... */
 	foptvallen=sizeof(foptval);
 	if (getsockopt( udp_sock, SOL_SOCKET, SO_RCVBUF, (void*) &foptval,
 		    &foptvallen) == -1 )
 	{
 		LOG(L_ERR, "ERROR: udp_init: getsockopt: %s\n", strerror(errno));
8eddd6f6
 		return -1;
d24a2059
 	}
e22bbdb8
 	LOG(L_INFO, "INFO: udp_init: SO_RCVBUF is finally %d\n", foptval );
d24a2059
 
8eddd6f6
 	return 0;
d24a2059
 
 	/* EoJKU */
8eddd6f6
 }
 
2ba73117
 
 #ifdef USE_MCAST
 
 /*
  * Setup multicast receiver
  */
 static int setup_mcast_rcvr(int sock, union sockaddr_union* addr)
 {
 	struct ip_mreq mreq;
 #ifdef USE_IPV6
 	struct ipv6_mreq mreq6;
 #endif /* USE_IPV6 */
 	
 	if (addr->s.sa_family==AF_INET){
 		memcpy(&mreq.imr_multiaddr, &addr->sin.sin_addr, 
 		       sizeof(struct in_addr));
 		mreq.imr_interface.s_addr = htonl(INADDR_ANY);
 		
 		if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,&mreq,
 			       sizeof(mreq))==-1){
 			LOG(L_ERR, "ERROR: setup_mcast_rcvr: setsockopt: %s\n",
 			    strerror(errno));
 			return -1;
 		}
 		
 #ifdef USE_IPV6
 	} else if (addr->s.sa_family==AF_INET6){
 		memcpy(&mreq6.ipv6mr_multiaddr, &addr->sin6.sin6_addr, 
 		       sizeof(struct in6_addr));
 		mreq6.ipv6mr_interface = 0;
d3d1486e
 #ifdef __OS_linux
2ba73117
 		if (setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6,
d3d1486e
 #else
 		if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6,
 #endif
2ba73117
 			       sizeof(mreq6))==-1){
 			LOG(L_ERR, "ERROR: setup_mcast_rcvr: setsockopt:%s\n",
 			    strerror(errno));
 			return -1;
 		}
 		
 #endif /* USE_IPV6 */
 	} else {
e6b442bd
 		LOG(L_ERR, "ERROR: setup_mcast_rcvr: Unsupported protocol family\n");
2ba73117
 		return -1;
 	}
 	return 0;
 }
 
 #endif /* USE_MCAST */
 
 
36ef0329
 int udp_init(struct socket_info* sock_info)
8eddd6f6
 {
4e2fdd79
 	union sockaddr_union* addr;
e22bbdb8
 	int optval;
90c6c74a
 #ifdef USE_MCAST
 	unsigned char m_ttl, m_loop;
 #endif
741db913
 	addr=&sock_info->su;
 /*
e3dccdc9
 	addr=(union sockaddr_union*)pkg_malloc(sizeof(union sockaddr_union));
8eddd6f6
 	if (addr==0){
 		LOG(L_ERR, "ERROR: udp_init: out of memory\n");
 		goto error;
 	}
741db913
 */
f2f969dd
 	sock_info->proto=PROTO_UDP;
6eacb2bc
 	if (init_su(addr, &sock_info->address, sock_info->port_no)<0){
4e2fdd79
 		LOG(L_ERR, "ERROR: udp_init: could not init sockaddr_union\n");
 		goto error;
 	}
1d597ac3
 	
36ef0329
 	sock_info->socket = socket(AF2PF(addr->s.sa_family), SOCK_DGRAM, 0);
 	if (sock_info->socket==-1){
8eddd6f6
 		LOG(L_ERR, "ERROR: udp_init: socket: %s\n", strerror(errno));
 		goto error;
 	}
 	/* set sock opts? */
 	optval=1;
36ef0329
 	if (setsockopt(sock_info->socket, SOL_SOCKET, SO_REUSEADDR ,
853c176f
 					(void*)&optval, sizeof(optval)) ==-1){
 		LOG(L_ERR, "ERROR: udp_init: setsockopt: %s\n", strerror(errno));
 		goto error;
 	}
39546e5f
 	/* tos */
fe09f315
 	optval = tos;
39546e5f
 	if (setsockopt(sock_info->socket, IPPROTO_IP, IP_TOS, (void*)&optval, 
 			sizeof(optval)) ==-1){
 		LOG(L_WARN, "WARNING: udp_init: setsockopt tos: %s\n", strerror(errno));
 		/* continue since this is not critical */
 	}
f3a26797
 #if defined (__OS_linux) && defined(UDP_ERRORS)
853c176f
 	optval=1;
 	/* enable error receiving on unconnected sockets */
 	if(setsockopt(sock_info->socket, SOL_IP, IP_RECVERR,
 					(void*)&optval, sizeof(optval)) ==-1){
8eddd6f6
 		LOG(L_ERR, "ERROR: udp_init: setsockopt: %s\n", strerror(errno));
f3a26797
 		goto error;
 	}
 #endif
 #if defined (__OS_linux)
 	/* if pmtu_discovery=1 then set DF bit and do Path MTU discovery
 	 * disabled by default */
 	optval= (pmtu_discovery) ? IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
 	if(setsockopt(sock_info->socket, IPPROTO_IP, IP_MTU_DISCOVER,
 			(void*)&optval, sizeof(optval)) ==-1){
 		LOG(L_ERR, "ERROR: udp_init: setsockopt: %s\n", strerror(errno));
8eddd6f6
 		goto error;
 	}
853c176f
 #endif
 
2ba73117
 #ifdef USE_MCAST
 	if ((sock_info->flags & SI_IS_MCAST) 
 	    && (setup_mcast_rcvr(sock_info->socket, addr)<0)){
 			goto error;
 	}
e6b442bd
 	/* set the multicast options */
 	if (addr->s.sa_family==AF_INET){
90c6c74a
 		m_loop=mcast_loopback;
e6b442bd
 		if (setsockopt(sock_info->socket, IPPROTO_IP, IP_MULTICAST_LOOP, 
90c6c74a
 						&m_loop, sizeof(m_loop))==-1){
741a9937
 			LOG(L_WARN, "WARNING: udp_init: setsockopt(IP_MULTICAST_LOOP):"
 						" %s\n", strerror(errno));
 			/* it's only a warning because we might get this error if the
 			  network interface doesn't support multicasting -- andrei */
e6b442bd
 		}
 		if (mcast_ttl>=0){
90c6c74a
 			m_ttl=mcast_ttl;
e6b442bd
 			if (setsockopt(sock_info->socket, IPPROTO_IP, IP_MULTICAST_TTL,
90c6c74a
 						&m_ttl, sizeof(m_ttl))==-1){
741a9937
 				LOG(L_WARN, "WARNING: udp_init: setsockopt (IP_MULTICAST_TTL):"
e6b442bd
 						" %s\n", strerror(errno));
 			}
 		}
 #ifdef USE_IPV6
 	} else if (addr->s.sa_family==AF_INET6){
 		if (setsockopt(sock_info->socket, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, 
 						&mcast_loopback, sizeof(mcast_loopback))==-1){
741a9937
 			LOG(L_WARN, "WARNING: udp_init: setsockopt (IPV6_MULTICAST_LOOP):"
e6b442bd
 					" %s\n", strerror(errno));
 		}
 		if (mcast_ttl>=0){
 			if (setsockopt(sock_info->socket, IPPROTO_IP, IPV6_MULTICAST_HOPS,
 							&mcast_ttl, sizeof(mcast_ttl))==-1){
741a9937
 				LOG(L_WARN, "WARNING: udp_init: setssckopt "
 						"(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
e6b442bd
 			}
 		}
 #endif /* USE_IPV6*/
 	} else {
 		LOG(L_ERR, "ERROR: udp_init: Unsupported protocol family %d\n",
 					addr->s.sa_family);
 		goto error;
 	}
2ba73117
 #endif /* USE_MCAST */
8eddd6f6
 
36ef0329
 	if ( probe_max_receive_buffer(sock_info->socket)==-1) goto error;
53531528
 	
741db913
 	if (bind(sock_info->socket,  &addr->s, sockaddru_len(*addr))==-1){
36ef0329
 		LOG(L_ERR, "ERROR: udp_init: bind(%x, %p, %d) on %s: %s\n",
 				sock_info->socket, &addr->s, 
4d080f49
 				(unsigned)sockaddru_len(*addr),
36ef0329
 				sock_info->address_str.s,
 				strerror(errno));
 	#ifdef USE_IPV6
 		if (addr->s.sa_family==AF_INET6)
 			LOG(L_ERR, "ERROR: udp_init: might be caused by using a link "
 					" local address, try site local or global\n");
 	#endif
e60a9728
 		goto error;
 	}
 
e3dccdc9
 /*	pkg_free(addr);*/
e60a9728
 	return 0;
 
 error:
e3dccdc9
 /*	if (addr) pkg_free(addr);*/
e60a9728
 	return -1;
 }
 
 
 
 int udp_rcv_loop()
 {
3e429f5c
 	unsigned len;
dda9dab1
 #ifdef DYN_BUF
22d4aa5d
 	char* buf;
dda9dab1
 #else
b2dec9c6
 	static char buf [BUF_SIZE+1];
dda9dab1
 #endif
5260ef32
 	char *tmp;
4e2fdd79
 	union sockaddr_union* from;
9c61e9f9
 	unsigned int fromlen;
f2f969dd
 	struct receive_info ri;
e60a9728
 
dda9dab1
 
e3dccdc9
 	from=(union sockaddr_union*) pkg_malloc(sizeof(union sockaddr_union));
e60a9728
 	if (from==0){
efeaaf53
 		LOG(L_ERR, "ERROR: udp_rcv_loop: out of memory\n");
e60a9728
 		goto error;
 	}
741db913
 	memset(from, 0 , sizeof(union sockaddr_union));
f2f969dd
 	ri.bind_address=bind_address; /* this will not change, we do it only once*/
 	ri.dst_port=bind_address->port_no;
 	ri.dst_ip=bind_address->address;
 	ri.proto=PROTO_UDP;
 	ri.proto_reserved1=ri.proto_reserved2=0;
9188021a
 
 	/* initialize the config framework */
 	if (cfg_child_init()) goto error;
 
e60a9728
 	for(;;){
dda9dab1
 #ifdef DYN_BUF
6bd84753
 		buf=pkg_malloc(BUF_SIZE+1);
 		if (buf==0){
 			LOG(L_ERR, "ERROR: udp_rcv_loop: could not allocate receive"
 					 " buffer\n");
 			goto error;
 		}
dda9dab1
 #endif
741db913
 		fromlen=sockaddru_len(bind_address->su);
36ef0329
 		len=recvfrom(bind_address->socket, buf, BUF_SIZE, 0, &from->s,
 											&fromlen);
e60a9728
 		if (len==-1){
5260ef32
 			if (errno==EAGAIN){
 				DBG("udp_rcv_loop: packet with bad checksum received\n");
 				continue;
 			}
6984881e
 			LOG(L_ERR, "ERROR: udp_rcv_loop:recvfrom:[%d] %s\n",
 						errno, strerror(errno));
5260ef32
 			if ((errno==EINTR)||(errno==EWOULDBLOCK)|| (errno==ECONNREFUSED))
6984881e
 				continue; /* goto skip;*/
e60a9728
 			else goto error;
 		}
8fc80c33
 		/* we must 0-term the messages, receive_msg expects it */
610cb10e
 		buf[len]=0; /* no need to save the previous char */
577f13b5
 
5260ef32
 		ri.src_su=*from;
 		su2ip_addr(&ri.src_ip, from);
 		ri.src_port=su_getport(from);
 
577f13b5
 #ifndef NO_ZERO_CHECKS
96227c65
 #ifdef USE_STUN
 		/* STUN support can be switched off even if it's compiled */
 		if (stun_allow_stun == 0 || (unsigned char)*buf != 0x00) {
 #endif
 		  if (len<MIN_UDP_PACKET) {
 			  tmp=ip_addr2a(&ri.src_ip);
 			  DBG("udp_rcv_loop: probing packet received from %s %d\n",
 				  	tmp, htons(ri.src_port));
 			  continue;
 		  }
 #ifdef USE_STUN
577f13b5
 		}
96227c65
 #endif
35ab13d8
 /* historically, zero-terminated packets indicated a bug in clients
  * that calculated wrongly packet length and included string-terminating
  * zero; today clients exist with legitimate binary payloads and we
  * shall not check for zero-terminated payloads
  */
 #ifdef TRASH_ZEROTERMINATED_PACKETS
577f13b5
 		if (buf[len-1]==0) {
5260ef32
 			tmp=ip_addr2a(&ri.src_ip);
 			LOG(L_WARN, "WARNING: udp_rcv_loop: "
 					"upstream bug - 0-terminated packet from %s %d\n",
 					tmp, htons(ri.src_port));
577f13b5
 			len--;
 		}
 #endif
96227c65
 #endif
f354fb0e
 #ifdef DBG_MSG_QA
 		if (!dbg_msg_qa(buf, len)) {
e3fc93f4
 			LOG(L_WARN, "WARNING: an incoming message didn't pass test,"
 						"  drop it: %.*s\n", len, buf );
f354fb0e
 			continue;
 		}
 #endif
5260ef32
 		if (ri.src_port==0){
 			tmp=ip_addr2a(&ri.src_ip);
 			LOG(L_INFO, "udp_rcv_loop: dropping 0 port packet from %s\n", tmp);
 			continue;
 		}
f2f969dd
 		
38c052a7
 		/* update the local config */
 		cfg_update();
96227c65
 #ifdef USE_STUN
 			/* STUN support can be switched off even if it's compiled */
 			if (stun_allow_stun && (unsigned char)*buf == 0x00) {
 			    /* stun_process_msg releases buf memory if necessary */
 				if ((stun_process_msg(buf, len, &ri)) != 0) {
 					continue; /* some error occurred */
 				}
 			} else
 #endif
22d4aa5d
 		/* receive_msg must free buf too!*/
f2f969dd
 		receive_msg(buf, len, &ri);
1b1b19d8
 		
b2dec9c6
 	/* skip: do other stuff */
e60a9728
 		
 	}
51eadd0c
 	/*
e3dccdc9
 	if (from) pkg_free(from);
e60a9728
 	return 0;
51eadd0c
 	*/
e60a9728
 	
 error:
e3dccdc9
 	if (from) pkg_free(from);
e60a9728
 	return -1;
 }
 
 
 
92044adc
 
e6a2b12e
 /* send buf:len over udp to dst (uses only the to and send_sock dst members)
  * returns the numbers of bytes sent on success (>=0) and -1 on error
  */
 int udp_send(struct dest_info* dst, char *buf, unsigned len)
577f13b5
 {
 
 	int n;
741db913
 	int tolen;
e6a2b12e
 	struct ip_addr ip; /* used only on error, for debugging */
577f13b5
 
 #ifdef DBG_MSG_QA
 	/* aborts on error, does nothing otherwise */
f354fb0e
 	if (!dbg_msg_qa( buf, len )) {
 		LOG(L_ERR, "ERROR: udp_send: dbg_msg_qa failed\n");
 		abort();
 	}
577f13b5
 #endif
 
e6a2b12e
 	tolen=sockaddru_len(dst->to);
e60a9728
 again:
e6a2b12e
 	n=sendto(dst->send_sock->socket, buf, len, 0, &dst->to.s, tolen);
18abd66c
 #ifdef XL_DEBUG
 	LOG(L_INFO, "INFO: send status: %d\n", n);
 #endif
e60a9728
 	if (n==-1){
e6a2b12e
 		su2ip_addr(&ip, &dst->to);
839c9509
 		LOG(L_ERR, "ERROR: udp_send: sendto(sock,%p,%u,0,%s:%d,%d): %s(%d)\n",
e6a2b12e
 				buf,len, ip_addr2a(&ip), su_getport(&dst->to), tolen,
9dfa5dc4
 				strerror(errno),errno);
e60a9728
 		if (errno==EINTR) goto again;
d3b31abd
 		if (errno==EINVAL) {
 			LOG(L_CRIT,"CRITICAL: invalid sendtoparameters\n"
68a3fc65
 			"one possible reason is the server is bound to localhost and\n"
 			"attempts to send to the net\n");
d3b31abd
 		}
e60a9728
 	}
 	return n;
 }