this is 0.1.3

- Bugfixes in the SIP proxy part
 - Performance imporvement in RTP proxy part
 - some documentation updates
 - include ./scripts subdirectory in the distribution,
   was an error in the autoconf/automake setup

ChangeLog

@@ -1,3 +1,21 @@
+0.1.3
+=====
+- 11-Sep-2002:	- Fixed a error in the autoconf/automake part of the project.
+		  (scripts subdirectory was missing in the tar.gz archive.
+		  This resulted in an error during ./configure - complaining
+		  about non existent install-sh script)
+		- startup is more silent - set initial debug level to 0
+- 10-Sep-2002:	- Some (yea, I know...) -minor- docu updates
+-  8-Sep-2002:	- Masquerade Contact Headers of inbound clients
+		  (Contact header will be used by the remote SIP
+		  user agent to directly contact the local user agent -
+		  and bypassing the proxy. This of course will *not* work
+		  if the local user agent is located in a private IP range.)
+		- Performance optimizations in RTP proxy
+		- Bugfix: now masqueraded clients work with any
+		  SIP port (other than 5060). Before, incomming
+		  requests/responses where always sent to port 5060.
+
 0.1.2
 =====
 -  7-Sep-2002:	- Releases version 0.1.2

Makefile.am

@@ -21,4 +21,4 @@
 
 SUBDIRS = src doc
 
-EXTRA_DIST = TODO RELNOTES
+EXTRA_DIST = scripts TODO RELNOTES

Makefile.in

@@ -87,7 +87,7 @@ VERSION = @VERSION@
 
 SUBDIRS = src doc
 
-EXTRA_DIST = TODO RELNOTES
+EXTRA_DIST = scripts TODO RELNOTES
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 mkinstalldirs = $(SHELL) $(top_srcdir)/scripts/mkinstalldirs
 CONFIG_HEADER = config.h

README

@@ -4,8 +4,8 @@ Be warned, this (and all the other) documentantation is far from
 complete. This is still considered an alpha release.
 
 
-Overview:
+OVERVIEW
-=========
+========
 Siprox is an proxy/masquerading daemon for the SIP protocol.
 It handles registrations of SIP clients on a private IP network
 and performs rewriting of the SIP message bodies to make SIP
@@ -20,17 +20,18 @@ IP addresses and port numbers.
 
 
 
-Requirements:
+REQUIREMENTS
-=============
+============
 - libosip-0.8.8		(http://www.fsf.org/software/osip/)
+- pthreads		(should be part of any Linux distribution)
 
-Up to now, this packages only has been tested under an i386 Redhat Linux 6.0.
+Up to now, siporxd only has been tested under an i386 Redhat Linux 6.0.
 However, it should build and run under newer versions (feedback is welcome).
 
 
 
-How to get started:
+HOW TO GET STARTED
-===================
+==================
 
 - ./configure
 
@@ -38,82 +39,124 @@ How to get started:
 
 - make install
 
-- copy sipproxd.conf.example to /etc/siproxd.conf
+- copy doc/sipproxd.conf.example to /etc/siproxd.conf
 
 - edit /etc/siproxd.conf according to your situation
-  At least 'host_inbound' and 'host_outbound' have to be adapted!
+  At least 'host_inbound' and 'host_outbound' *must* be adapted!
-  host_inbound is your IP address of your private network,
+  'host_inbound' is the firewalls IP address of your private network,
-  host_outbound is your publich IP address or hostname (if you
+  'host_outbound' is the  publich IP address or hostname of the
-  have dynamic IP addresses, then you might want to use a hostname
+  firewall. (If you have dynamic IP addresses, then you might want
-  here and use a dynamic DNS service like dyndns.org)
+  to use a hostname here and use a dynamic DNS service like [1])
+
+- start siproxd (siproxd does *not* require root privilegdes)
+  $ siproxd
 
 
-
+WHAT SIPROXD DOES
-What siproxd does:
 =================
-Siproxd's main purpose (up to now) is to rewrite SIP messages
+Siproxd's purpose is to act as an SIP proxy for softphones located
-to be able to operate via an masquerading firewall.
+in private IP ranges. Therefore it will rewrite SIP messages to allow a
-Since release 0.1.2 siproxd can proxy incomming RTP streams.
+softphone to communicate to a counterpart that is located in the Internet.
+There usually will be a masquerading firewall in between to 'hide' the
+private IP range (either via NAT - network address translation or 
+masuerading). Check the scenario drawn below.
 
-
+With release 0.1.2 siproxd is also able to proxy incomming RTP data
-
+streams. The config parameters 'rtp_port_low' and rtp_port_high' define
-What siproxd does NOT do:
-=========================
-
-SINCE RELEASE 0.1.2:
-  Siproxd should be able to proxy incomming RTP data streams (UDP only).
-  This is still very experimental code ;-)
-  The config parameters 'rtp_port_low' and rtp_port_high' define
 the port range that siproxd will use for incomming RTP data streams.
 'rtp_timeout' defines after what time an unused  (no data received)
 rtp stream is considered dead and removed.
 
-  ** As I had not yet the possibility to test this feature,
+** RTP data stream proxying is still experimental code.
-  ** I'd be glad about feedback.
+** As I had not yet the possibility to test this feature extensively,
-
+** I'm happy about any feedback.
-PRIOR TO RELEASE 0.1.2:
-  Siproxd does *not* (yet) create masquerading tunnels or port-forwarding
-  for the data stream through the firewall.
-
-  These forwarding rules have to be set-up manually (currently)
-
-  Example, using ipchains (mfw):
-  # ipchains -A input --proto udp --dport 7078 -m 100 -j ACCEPT
-  # ipmasqadm mfw -A -m 100 -r <remoteaddress> 7078
-
-  Example, using ipchains (portfw):
-  # portfw -a -P udp -L <localaddress> 7078 -R <remoteaddress> 7078
 
 
 
-Limitations:
+Scenario
-============
+--------
-- currently, only UDP is supported
+
-- very likely it does not follow the SIP spec in all details ;-)
+ private IP address range             :          Internet
+ 10.0.0.x                             :          (publich IP address range)
+                                      :
+                                      :         foo.bar.org
+ +-------------+	       +--------------+
+ !             !.10	    .1 ! masquerading ! publicIP
+ ! IntHost     !---------------! Firewall     !------------>>  
+ !             !               !              !   
+ +-------------+	       +--------------+
+                                      :
 
 
 
-Important Notice:
+ - The Firewall does IP masquerading and is running siproxd
-=================
+
-The gethostbyname() function leaks memory in RedHat 6.0 with glibc 2.1.1.
+ - IntHost is running an SIP softphone (like linphone, kphone)
-The quick fix is to delete nisplus service from hosts entry in
+
-/etc/nsswitch.conf. In my tests, memory use remained stable after I
+ - The SIP address used by the softphone is sip:johndoe@foo.bar.org
-made the mentioned change.
+
+ - The softphone is configured to register itself at siproxd
+   running on the firewall host (10.0.0.1) as sip:johndoe@foo.bar.org
+
+ - foo.bar.org is the domain name corresponding to the public IP address
+   of the firewall (eg use some dynamic DNS service [1])
+
+ Firewall rules for incomming traffic (ipchains example):
+ $ ipchains -A input --proto udp --dport 5060 --log  -j ACCEPT
+ $ ipchains -A input --proto udp --dport 7070:7080   -j ACCEPT
+
+ The first line will allow incomming SIP traffic. The second line will
+ allow incomming RTP traffic on the ports 7070 - 7080 (the default port
+ range used by siproxd for incomming RTP traffic).
+
+
+
+REFERENCES
+==========
+[1] dynamic DNS service http://www.dyndns.org
+
+
+
+LIMITATIONS
+===========
+- currently, the SIP part only supports UDP
+- RTP proxy support is still experimantal (so as the rest of siproxd ;-)
+- very likely it does not follow the SIP spec (RFC3261) in all details
+- check the TODO file for more things that we-cannot-do-but-would-like-to
+
+
+IMPORTANT NOTICE
+================
+The gethostbyname() function leaks memory in glibc 2.1.1 (-> RedHat 6.0).
+The quick fix is to delete the nisplus service from hosts entry in
+/etc/nsswitch.conf.
+In my tests, memory use remained stable after I made the mentioned change.
+
 (source: http://www.squid-cache.org/Doc/FAQ/FAQ-14.html)
 
 
-Contacts:
+CONTACTS
-=========
+========
 Please feel free to contact the author to:
-   - provide feedback
+   - provide feedback, report bugs,
-   - report bugs,
    - request for additional features
    - report interoperability with softphones
    - ...
 
 and visit the website at http://siproxd.sourceforge.net/
 
+There also is a siproxd mailinglist available on sourceforge.
+
 Thomas Ries  (tries@gmx.net)
    GnuPG Public Key:
    pub  1024D/87BCDC94 2000-03-19 Thomas Ries (tries@gmx.net)
    Key fingerprint = 13D1 19F5 77D0 4CEC 8D3F  A24E 09FC C18A 87BC DC94
+
+
+
+CREDITS
+=======
+
+Thanks to sourceforge.net for providing the distribution platform and
+infrastructure.
+

TODO

@@ -1,20 +1,19 @@
-TODOs, in anarchistic order:
+TODOs, in random order:
-============================
+=======================
-
 
 - re-think the registration mechanism (mapping and decision criteria
   for in- and outgoing stuff...
   
-- 2.2.x kernels:
-  make use of the portfw.so (ipmasqadm package) to create forwarding
-  tunnels for incomming data streams
-  How to determine when finished? Is it possible to keep it stateless?
-
-- Is there a possibility to open up an masquerading tunnel by
-  a userspace program on the firewall?
-
 - logging via syslog if running in daemon mode
 
 - get_ip_by_host: reduce DNS timeouts
 
+- Documentation
+
+- automagically create a proper config file during install
+
+- client authentication
+
+- portability to other platforms / operating systems
+  first goal: other Unixes
 

config.h.in

@@ -21,18 +21,57 @@
 /* Define if your <sys/time.h> declares struct tm.  */
 #undef TM_IN_SYS_TIME
 
+/* Define if you have the bind function.  */
+#undef HAVE_BIND
+
+/* Define if you have the fgets function.  */
+#undef HAVE_FGETS
+
+/* Define if you have the gethostbyname function.  */
+#undef HAVE_GETHOSTBYNAME
+
+/* Define if you have the getopt_long_only function.  */
+#undef HAVE_GETOPT_LONG_ONLY
+
+/* Define if you have the read function.  */
+#undef HAVE_READ
+
 /* Define if you have the select function.  */
 #undef HAVE_SELECT
 
+/* Define if you have the send function.  */
+#undef HAVE_SEND
+
+/* Define if you have the sendto function.  */
+#undef HAVE_SENDTO
+
 /* Define if you have the socket function.  */
 #undef HAVE_SOCKET
 
+/* Define if you have the sprintf function.  */
+#undef HAVE_SPRINTF
+
+/* Define if you have the sscanf function.  */
+#undef HAVE_SSCANF
+
+/* Define if you have the strchr function.  */
+#undef HAVE_STRCHR
+
 /* Define if you have the strerror function.  */
 #undef HAVE_STRERROR
 
+/* Define if you have the strncpy function.  */
+#undef HAVE_STRNCPY
+
 /* Define if you have the strstr function.  */
 #undef HAVE_STRSTR
 
+/* Define if you have the vfprintf function.  */
+#undef HAVE_VFPRINTF
+
+/* Define if you have the <errno.h> header file.  */
+#undef HAVE_ERRNO_H
+
 /* Define if you have the <stdarg.h> header file.  */
 #undef HAVE_STDARG_H
 

configure.in

@@ -1,3 +1,13 @@
+dnl
+dnl	History
+dnl	-------
+dnl	before time		a lot happend before start of history
+dnl	8-Sep-2002   tries	included more tests for used functions
+dnl
+dnl
+dnl
+dnl
+
 dnl Process this file with autoconf to produce a configure script.
 AC_INIT(src/siproxd.c)
 
@@ -5,7 +15,7 @@ dnl ******************************************************************
 dnl
 SPD_MAJOR_VERSION=0
 SPD_MINOR_VERSION=1
-SPD_MICRO_VERSION=2
+SPD_MICRO_VERSION=3
 SPD_VERSION=$SPD_MAJOR_VERSION.$SPD_MINOR_VERSION.$SPD_MICRO_VERSION
 
 dnl *********************************************************************
@@ -26,7 +36,7 @@ AC_CHECK_LIB(pthread, pthread_create)
 
 dnl Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS(sys/time.h unistd.h)
+AC_CHECK_HEADERS(sys/time.h unistd.h errno.h)
 AC_CHECK_HEADERS(stdarg.h varargs.h)
 
 dnl Checks for typedefs, structures, and compiler characteristics.
@@ -38,7 +48,12 @@ AC_STRUCT_TM
 dnl Checks for library functions.
 AC_FUNC_MEMCMP
 AC_FUNC_VPRINTF
-AC_CHECK_FUNCS(select socket strerror strstr)
+AC_CHECK_FUNCS(strerror)
+AC_CHECK_FUNCS(gethostbyname)
+AC_CHECK_FUNCS(socket bind select read send sendto)
+AC_CHECK_FUNCS(getopt_long_only)
+AC_CHECK_FUNCS(strncpy strchr strstr sprintf vfprintf fgets sscanf)
+
 
 AC_OUTPUT(Makefile \
 src/Makefile \

doc/siproxd.conf.example

@@ -4,20 +4,6 @@
 # !! This is a sample file, adapt it to your needs before using it
 #
 
-######################################################################
-#  DBCLASS_BABBLE  0x00000001	   // babble (like entering/leaving fnc)
-#  DBCLASS_NET     0x00000002	   // network
-#  DBCLASS_SIP     0x00000004	   // SIP manipulations
-#  DBCLASS_REG     0x00000008	   // Client registration
-#  DBCLASS_NOSPEC  0x00000010	   // non specified class
-#  DBCLASS_PROXY   0x00000020	   // proxy
-#  DBCLASS_DNS     0x00000040	   // DNS stuff
-#  DBCLASS_NETTRAF 0x00000080	   // network traffic
-#  DBCLASS_CONFIG  0x00000100	   // configuration
-#  DBCLASS_RTP     0x00000200      // RTP proxy
-#
-debug_level = 0x000002fe
-
 ######################################################################
 # The IP addresses of the INBOUND and OUTBOUND interface can
 # be specified as hostnames or in dotted decimal form:
@@ -59,8 +45,22 @@ rtp_port_high = 7080
 
 ######################################################################
 # Timeout for RTP streams
-#    after this number of seconds, at RTP stream is considered dead
+#    after this number of seconds, an RTP stream is considered dead
 #    and proxying it will be stopped.
 #    
 rtp_timeout = 60
 
+######################################################################
+#  DBCLASS_BABBLE  0x00000001	   // babble (like entering/leaving fnc)
+#  DBCLASS_NET     0x00000002	   // network
+#  DBCLASS_SIP     0x00000004	   // SIP manipulations
+#  DBCLASS_REG     0x00000008	   // Client registration
+#  DBCLASS_NOSPEC  0x00000010	   // non specified class
+#  DBCLASS_PROXY   0x00000020	   // proxy
+#  DBCLASS_DNS     0x00000040	   // DNS stuff
+#  DBCLASS_NETTRAF 0x00000080	   // network traffic
+#  DBCLASS_CONFIG  0x00000100	   // configuration
+#  DBCLASS_RTP     0x00000200      // RTP proxy
+#
+debug_level =      0x00000218
+

src/proxy.c

@@ -41,10 +41,6 @@ static char const ident[]="$Id: " __FILE__ ": " PACKAGE "-" VERSION "-"\
 /* configuration storage */
 extern struct siproxd_config configuration;
 
-/*
- * knows hot to rewrite the SIP URLs in a request/response
- */
-
 extern int errno;
 extern struct urlmap_s urlmap[];		/* URL mapping table     */
 extern struct lcl_if_s local_addresses;
@@ -60,7 +56,7 @@ int proxy_request (sip_t *request) {
    int sts;
    int type;
    struct in_addr addr;
-//   contact_t *contact; /* contact header issue */
+   contact_t *contact;
    url_t *url;
    int port;
    char *buffer;
@@ -77,25 +73,6 @@ int proxy_request (sip_t *request) {
       return 1;
    }
 
-#if 0 /* Contact Header Issue */
-   /* figure out if this is an request comming from the outside
-    * world to one of our registered clients ('to' == 'masq' URL)
-    * or if this is a request sent by on e of our registered clients
-    * ('from' == 'true' URL) 
-    */
-   msg_getcontact(request,0,&contact);
-
-   /* seen with linphone-0.9.1pre1 w/ user-agent: oSIP/Linphone-0.8.0
-      no contact header in reequest */
-   if (contact==NULL) {
-      ERROR("Contact header is missing!");
-      /* THIS IS SEVERE - I HAVE NO WAY TO FIGURE OUT WHO THE
-         REAL CLIENT IS BEHIND THIS PACKET...
-         what can I do here?  */
-      return 1;
-   }
-#endif
-   
    type = 0;
    for (i=0; i<URLMAP_SIZE; i++) {
       if (urlmap[i].active == 0) continue;
@@ -109,16 +86,6 @@ int proxy_request (sip_t *request) {
 	 break;
       }
 
-#if 0 /* Contact Header Issue */
-      /* outgoing request ('contact' == 'true') */
-      if (compare_url(contact->url, urlmap[i].true_url)==0) {
-         type=REQTYP_OUTGOING;
-         DEBUGC(DBCLASS_PROXY,"outgoing request from %s@%s from inbound",
-	        request->from->url->username,
-		request->from->url->host);
-	 break;
-      }
-#endif
       /* outgoing request ('from' == 'masq') */
       if (compare_url(request->from->url, urlmap[i].masq_url)==0) {
          type=REQTYP_OUTGOING;
@@ -146,11 +113,23 @@ int proxy_request (sip_t *request) {
       url=msg_geturi(request);
       free(url->host);url->host=NULL;
 {
-      char *copy;
+      char *host;
-      copy = (char *)malloc(strlen(urlmap[i].true_url->host)+1);
+      char *port;
-      memcpy(copy, urlmap[i].true_url->host, strlen(urlmap[i].true_url->host));
+      /* set the true host */
-      copy[strlen(urlmap[i].true_url->host)]='\0';
+      if(urlmap[i].true_url->host) {
-      url_sethost(url, copy);
+	 host = (char *)malloc(strlen(urlmap[i].true_url->host)+1);
+	 memcpy(host, urlmap[i].true_url->host, strlen(urlmap[i].true_url->host));
+	 host[strlen(urlmap[i].true_url->host)]='\0';
+	 url_sethost(url, host);
+      }
+
+      /* set the true port */
+      if(urlmap[i].true_url->port) {
+	 port = (char *)malloc(strlen(urlmap[i].true_url->port)+1);
+	 memcpy(port, urlmap[i].true_url->port, strlen(urlmap[i].true_url->port));
+	 port[strlen(urlmap[i].true_url->port)]='\0';
+	 url_setport(url, port);
+      }
 }
 
       /* add my Via header line (inbound interface)*/
@@ -159,7 +138,7 @@ int proxy_request (sip_t *request) {
       /* if this is CANCEL/BYE request, stop RTP proxying */
       if (MSG_IS_BYE(request) || MSG_IS_CANCEL(request)) {
          /* stop the RTP proxying stream */
-         sts = rtp_stop_fwd(msg_getcall_id(request));
+         rtp_stop_fwd(msg_getcall_id(request));
       }
 
       break;
@@ -173,13 +152,36 @@ int proxy_request (sip_t *request) {
          sts = proxy_rewrite_invitation_body(request);
       }
 
+      /* rewrite Contact header to represent the masqued address */
+      msg_getcontact(request,0,&contact);
+      if (contact != NULL) {
+         for (i=0;i<URLMAP_SIZE;i++){
+	    if (urlmap[i].active == 0) continue;
+            if (compare_url(contact->url, urlmap[i].true_url)==0) break;
+         }
+         /* found a mapping entry */
+         if (i<URLMAP_SIZE) {
+            DEBUGC(DBCLASS_PROXY, "rewrote Contact header %s@%s -> %s@%s",
+	           contact->url->username, contact->url->host,
+		   urlmap[i].masq_url->username, urlmap[i].masq_url->host);
+            /* remove old entry */
+            list_remove(request->contacts,0);
+            contact_free(contact);
+            free(contact);
+            /* clone the masquerading url */
+	    contact_init(&contact);
+            url_clone(urlmap[i].masq_url, &contact->url);
+            list_add(request->contacts,contact,-1);
+         }     
+      }
+
       /* add my Via header line (outbound interface)*/
       sts = proxy_add_myvia(request, 0);
 
       /* if this is CANCEL/BYE request, stop RTP proxying */
       if (MSG_IS_BYE(request) || MSG_IS_CANCEL(request)) {
          /* stop the RTP proxying stream */
-         sts = rtp_stop_fwd(msg_getcall_id(request));
+         rtp_stop_fwd(msg_getcall_id(request));
       }
 
       break;
@@ -252,6 +254,7 @@ int proxy_response (sip_t *response) {
    int type;
    struct in_addr addr;
    via_t *via;
+   contact_t *contact;
    int port;
    char *buffer;
 
@@ -318,16 +321,6 @@ int proxy_response (sip_t *response) {
    * from an external host to the internal masqueraded host
    */
    case RESTYP_INCOMMING:
-#if 0 /* do we really have to?? in the incomming response
-         we have the correct address. But we must rewrite an
-	 outgoing response to an incomming INVITE request ! */
-      /* If an 200 answer to an INVITE request, rewrite body */
-      if ((MSG_IS_RESPONSEFOR(response,"INVITE") &&
-          (MSG_TEST_CODE(response, 200)) ) {
-         sts = proxy_rewrite_invitation_body(response);
-      }
-#endif
-
       break;
    
   /*
@@ -340,6 +333,30 @@ int proxy_response (sip_t *response) {
           (MSG_TEST_CODE(response, 200))) {
          sts = proxy_rewrite_invitation_body(response);
       }
+
+      /* rewrite Contact header to represent the masqued address */
+      msg_getcontact(response,0,&contact);
+      if (contact != NULL) {
+         for (i=0;i<URLMAP_SIZE;i++){
+	    if (urlmap[i].active == 0) continue;
+            if (compare_url(contact->url, urlmap[i].true_url)==0) break;
+         }
+         /* found a mapping entry */
+         if (i<URLMAP_SIZE) {
+            DEBUGC(DBCLASS_PROXY, "rewrote Contact header %s@%s -> %s@%s",
+	           contact->url->username, contact->url->host,
+		   urlmap[i].masq_url->username, urlmap[i].masq_url->host);
+            /* remove old entry */
+            list_remove(response->contacts,0);
+            contact_free(contact);
+            free(contact);
+            /* clone the masquerading url */
+	    contact_init(&contact);
+            url_clone(urlmap[i].masq_url, &contact->url);
+            list_add(response->contacts,contact,-1);
+         }     
+      }
+
       break;
    
    default:
@@ -529,7 +546,7 @@ int proxy_rewrite_invitation_body(sip_t *mymsg){
    sts = get_ip_by_host(configuration.outboundhost, &outb_addr);
    inb_clnt_port = atoi(sdp_m_port_get(sdp,0));
    /* start an RTP proxying stream */
-   sts = rtp_start_fwd(msg_getcall_id(mymsg),
+   rtp_start_fwd(msg_getcall_id(mymsg),
                        outb_addr, &outb_rtp_port,
 		       lcl_clnt_addr, inb_clnt_port);
 

src/siproxd.c

@@ -53,11 +53,11 @@ int main (int argc, char *argv[])
    extern char *optarg;
    int ch1;
    
-   char configfile[64]="siproxd";
+   char configfile[64]="siproxd";	/* basename of configfile */
-   int  config_search=1;
+   int  config_search=1;		/* search the config file */
 
    /* prepare default configuration */
-   configuration.debuglevel=-1;
+   configuration.debuglevel=0;
    configuration.daemonize=0;
    configuration.sip_listen_port=SIP_PORT;
    configuration.inboundhost=NULL;
@@ -121,7 +121,12 @@ int main (int argc, char *argv[])
    register_init();
 
    /* listen for incomming messages */
-   sipsock_listen();
+   sts=sipsock_listen();
+   if (sts != 0) {
+      /* failure to allocate SIP socket... */
+      ERROR("unable to bind to SIP listening socket - aborting"); 
+      return 0;
+   }
 
    /* initialize the RTP proxy thread */
    rtpproxy_init();

src/sock.c

@@ -21,6 +21,7 @@
 #include "config.h"
 
 #include <stdio.h>
+#include <errno.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
@@ -43,8 +44,6 @@ static char const ident[]="$Id: " __FILE__ ": " PACKAGE "-" VERSION "-"\
 /* configuration storage */
 extern struct siproxd_config configuration;
 
-extern int errno;
-
 static int listen_socket=0;
 
 /*
@@ -57,6 +56,7 @@ int sipsock_listen (void) {
 
    memset(&ipaddr, 0, sizeof(struct in_addr));
    listen_socket=sockbind(ipaddr, configuration.sip_listen_port);
+   if (listen_socket==0) return 1; /* failure*/
 
    DEBUGC(DBCLASS_NET,"bound listen socket %i",listen_socket);
    return 0;
@@ -121,9 +121,12 @@ int sipsock_send_udp(int *sock, struct in_addr addr, int port,
    sts = sendto (*sock, buffer, size, 0, &dst_addr, sizeof(dst_addr));
    
    if (sts == -1) {
+      if (errno != ECONNREFUSED) {
          ERROR("sendto() call failed:%s",strerror(errno));
          return 1;
       }
+     DEBUGC(DBCLASS_BABBLE,"sendto() call failed:%s",strerror(errno));
+   }
 
    return 0;
 }

src/utils.c

@@ -187,7 +187,7 @@ int get_ip_by_host(char *hostname, struct in_addr *addr) {
       if (dns_cache[i].hostname[0]=='\0') continue; /* empty */
       if (strcmp(hostname, dns_cache[i].hostname) == 0) { /* match */
          memcpy(addr, &dns_cache[i].addr, sizeof(struct in_addr));
-         DEBUGC(DBCLASS_DNS, "from cache: %s -> %s",
+         DEBUGC(DBCLASS_DNS, "DNS lookup - from cache: %s -> %s",
 	        hostname, inet_ntoa(*addr));
          return 0;
       }
@@ -202,7 +202,8 @@ int get_ip_by_host(char *hostname, struct in_addr *addr) {
    }
 
    memcpy(addr, hostentry->h_addr, sizeof(struct in_addr));
-   DEBUGC(DBCLASS_DNS, "resolved: %s -> %s", hostname, inet_ntoa(*addr));
+   DEBUGC(DBCLASS_DNS, "DNS lookup - resolved: %s -> %s",
+          hostname, inet_ntoa(*addr));
 
    /*
     * remember the result in the cache
@@ -221,7 +222,7 @@ int get_ip_by_host(char *hostname, struct in_addr *addr) {
    if (i >= DNS_CACHE_SIZE) i=j;
 
    /* store in cache */
-   DEBUGC(DBCLASS_DNS, "store into DNS cache, entry %i)", i);
+   DEBUGC(DBCLASS_DNS, "DNS lookup - store into cache, entry %i)", i);
    memset(&dns_cache[i], 0, sizeof(dns_cache[0]));
    strncpy(dns_cache[i].hostname, hostname, HOSTNAME_SIZE);
    time(&dns_cache[i].timestamp);
@@ -232,11 +233,14 @@ int get_ip_by_host(char *hostname, struct in_addr *addr) {
 
 /*
  * compares two URLs
- * returns 0 if equal, >0 if non equal, <0 if error
+ * returns 0 if equal, <0 if non equal, >0 if error
  * (by now, only hostname and username are compared)
  */
 int compare_url(url_t *url1, url_t *url2) {
    int sts;
+
+   if ((url1 == NULL) || (url2 == NULL)) return 1;
+
    /* comparison of hosts should be based on IP addresses, no? */
    DEBUGC(DBCLASS_BABBLE, "comparng urls: %s@%s -> %s@%s",
          url1->username, url1->host, url2->username, url2->host);