udp.c

用于linux环境下的SIP服务器

    FD_SET (ctx->out_socket, &memo_fdset);
  if (ctx->mcast_socket>0
      &&ctx->mcast_socket!=ctx->in_socket)
    FD_SET (ctx->mcast_socket, &memo_fdset);

  /* create a set of file descritor to control the stack */

  for (; max != 0; max--)
    {
      osip_fdset = memo_fdset;

      max_fd = ctx->in_socket;
      if (max_fd < ctx->out_socket)
	max_fd = ctx->out_socket;
      if (max_fd < ctx->mcast_socket)
	max_fd = ctx->mcast_socket;

      i = select (max_fd + 1, &osip_fdset, NULL, NULL, NULL);
      buf = (char *) osip_malloc (SIP_MESSAGE_MAX_LENGTH * sizeof (char) + 3);

      if (ipv6_enable==1)
	{
	  slen = sizeof (sa6);
	  sa = (struct sockaddr *)&sa6;
	}
      else
	{
	  slen = sizeof (sa4);
	  sa = (struct sockaddr *)&sa4;
	}

      if (0 == i)
	{
	  osip_free (buf);
	  return -1;		/* no message: timout expires */
	}
      else if (-1 == i)
	{
	  osip_free (buf);
	  return -2;		/* error */
	}
      else if (FD_ISSET (ctx->in_socket, &osip_fdset))
	{
	  OSIP_TRACE (osip_trace
		      (__FILE__, __LINE__, OSIP_INFO2, NULL,
		       "UDP MESSAGE RECEIVED\n"));
	  i = ppl_socket_recv (ctx->in_socket, buf, SIP_MESSAGE_MAX_LENGTH, 0,
			       sa, &slen);
	}
      else if (ctx->out_socket!=ctx->in_socket
	       &&FD_ISSET (ctx->out_socket, &osip_fdset))
	{
	  OSIP_TRACE (osip_trace
		      (__FILE__, __LINE__, OSIP_INFO2, NULL,
		       "UDP MESSAGE RECEIVED\n"));
	  i = ppl_socket_recv (ctx->out_socket, buf, SIP_MESSAGE_MAX_LENGTH, 0,
			       sa, &slen);
	}
      else if (ctx->mcast_socket>0
	       &&FD_ISSET (ctx->mcast_socket, &osip_fdset))
	{
	  OSIP_TRACE (osip_trace
		      (__FILE__, __LINE__, OSIP_INFO2, NULL,
		       "UDP MULTICAST MESSAGE RECEIVED\n"));
	  i =
	    ppl_socket_recv (ctx->mcast_socket, buf, SIP_MESSAGE_MAX_LENGTH, 0,
			     sa, &slen);
	}

      if (i > 0)
	{
	  char *ip_address = ppl_inet_ntop (sa);
	  /* Message might not end with a "\0" but we know the number of */
	  /* char received! */
	  osip_strncpy (buf + i, "\0", 1);
	  if (ip_address==NULL)
	    {
	      osip_free(buf);
	      return -1; /* missing information from socket?? */
	    }
	  if (ipv6_enable==1)
	    {
	      OSIP_TRACE (osip_trace
			  (__FILE__, __LINE__, OSIP_INFO2, NULL,
			   "udp plugin: RCV UDP MESSAGE (from %s:%i)\n",
			   ip_address, ntohs (sa6.sin6_port)));
	    }
	  else
	    {
	      OSIP_TRACE (osip_trace
			  (__FILE__, __LINE__, OSIP_INFO2, NULL,
			   "udp plugin: RCV UDP MESSAGE (from %s:%i)\n",
			   /* inet_ntoa (sa.sin_addr), ntohs (sa.sin_port))); */
			   ip_address, ntohs (sa4.sin_port)));
	    }
	  if (ctx->mcast_socket>0)
	    {
	      /* check maddr parameter to detect multicast data */
	      /* do they need special processing? */
	    }
#ifndef HIDE_MESSAGE
	  OSIP_TRACE (osip_trace
		      (__FILE__, __LINE__, OSIP_INFO1, NULL, "\n%s\n", buf));
#endif
	  if (ipv6_enable==1)
	    udp_process_message (buf, ip_address,
				 ntohs (sa6.sin6_port), i);
	  else
	    udp_process_message (buf, ip_address,
				 /* inet_ntoa (sa.sin_addr), */
				 ntohs (sa4.sin_port), i);
	  osip_free(ip_address);
	}
      else if (i == -1)
	{
	  if (errno == EAGAIN)
	    {
	      osip_free (buf);
	      return 0;
	    }
	  OSIP_TRACE (osip_trace
		      (__FILE__, __LINE__, OSIP_ERROR, NULL,
		       "udp plugin: error while receiving data!\n"));
	  osip_free (buf);
	  return -1;
	}
    }
  /* max is reached */
  return 1;
}

static int
__osip_message_fix_last_via_header (osip_message_t * request, char *ip_addr, int port)
{
  osip_generic_param_t *rport;
  osip_via_t *via;
  /* get Top most Via header: */
  if (request == NULL || request == NULL)
    return -1;
  if (MSG_IS_RESPONSE (request))
    return 0;			/* Don't fix Via header */

  via = osip_list_get (request->vias, 0);
  if (via == NULL || via->host == NULL)
    /* Hey, we could build it? */
    return -1;

  osip_via_param_get_byname (via, "rport", &rport);

  /* detect rport */
  if (rport != NULL)
    {
      if (rport->gvalue == NULL)
	{
	  rport->gvalue = (char *) osip_malloc (9);
#ifdef WIN32
	  _snprintf (rport->gvalue, 8, "%i", port);
#else
	  snprintf (rport->gvalue, 8, "%i", port);
#endif
	}			/* else bug? */
    }

  /* only add the received parameter if the 'sent-by' value does not contains
     this ip address */
  if (0 == osip_strcasecmp (via->host, ip_addr))	/* don't need the received parameter */
    return 0;
  else
    osip_via_set_received (via, osip_strdup (ip_addr));

  return 0;
}

int
udp_process_message (char *buf, char *ip_addr, int port, int length)
{
  osip_event_t *evt;

  if (buf == NULL
      || *buf == '\0'
      || buf[1] == '\0'
      || buf[2] == '\0' || buf[3] == '\0' || buf[4] == '\0' || buf[5] == '\0')
    {
      osip_free (buf);
      return -1;
    }

  evt = osip_parse (buf, length);
  osip_free (buf);
  if (evt == NULL)
    /* discard... */
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_ERROR, NULL,
		   "udp module: Could not parse response!\n"));
      return -1;
    }
  if (evt->sip == NULL)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_ERROR, NULL,
		   "udp module: Could not parse response!\n"));
      osip_event_free (evt);
      return -1;
    }
  udp_log_event (evt);

  /* modify the request to add a "received" parameter in the last Via. */
  /* for libosip>0.9.2 use osip_message_fix_last_via_header from osip */
  __osip_message_fix_last_via_header (evt->sip, ip_addr, port);

  if (evt->sip == NULL)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_ERROR, NULL,
		   "udp module: Probably a bad via header!\n"));
      osip_event_free (evt);
      return -1;
    }
  /* modify the request so it's compliant with the latest draft */
  psp_core_fix_strict_router_issue (evt);

  psp_core_event_add_sip_message (evt);
  return 0;
}


int
udp_log_event (osip_event_t * evt)
{
#ifdef SHOW_LIMITED_MESSAGE
  osip_via_t *via;
  osip_generic_param_t *b;

  via = osip_list_get (evt->sip->vias, 0);
  osip_via_param_get_byname (via, "branch", &b);
  if (b == NULL)
    {
      if (MSG_IS_REQUEST (evt->sip))
	{
	}
      else
	{
	}
      return -1;
    }
  if (MSG_IS_REQUEST (evt->sip))
    {
    }
  else
    {
    }
#endif
  return 0;
}

static int udp_plugin_get_new_socket(struct sockaddr_storage *addr)
{
  struct sockaddr_in6 raddr6;
  struct sockaddr_in raddr;
  int option;
  int i;

  int socket;

  OSIP_TRACE (osip_trace
	      (__FILE__, __LINE__, OSIP_WARNING, NULL,
	       "udp plugin: Building a new connect socket %i!\n",
	       ctx->in_port));
		
  if (ipv6_enable==1)
    socket = ppl_socket (PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
  else
    socket = ppl_socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);

  if (socket == -1)
    {
      OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			      "udp plugin: cannot create descriptor for port %i!\n"));
      return -1;
    }

  option = 1;
  i = setsockopt (socket, SOL_SOCKET, SO_REUSEADDR,
		  OPTVALCAST &option, sizeof option);
  if (i!=0)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_WARNING, NULL,
		   "upd plugin; UDP listener SO_REUSE_ADDR failed %i (%i)!\n",
		   ctx->in_port, i));
    }

  if (ipv6_enable==1)
    {
      memcpy ((void *)&(raddr6.sin6_addr.s6_addr), (const void *)&in6addr_any, 16);
      raddr6.sin6_port = htons (0);
      raddr6.sin6_family = AF_INET6;
      i = ppl_socket_bind (socket,
			   (struct sockaddr *) &raddr6, sizeof (raddr6));
    }
  else
    {
      raddr.sin_addr.s_addr = htons (INADDR_ANY);
      raddr.sin_port = htons (0);
      raddr.sin_family = AF_INET;
      i = ppl_socket_bind (socket,
			   (struct sockaddr *) &raddr, sizeof (raddr));
    }
  if (i < 0)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_WARNING, NULL,
		   "udp plugin: cannot bind on port %i!\n",
		   ctx->in_port));
      ppl_socket_close(socket);
      return -1;
    }

  i = connect(socket,(struct sockaddr *) addr,sizeof(struct sockaddr));
  if (i < 0)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_WARNING, NULL,
		   "udp plugin: cannot connect socket %i!\n",
		   ctx->in_port));
      ppl_socket_close(socket);
      return -1;
    }

  return socket;
}

/* return
   -1 on error
   0  on success
*/
int
cb_snd_udp_message (osip_transaction_t * transaction,	/* read only element */
		    osip_message_t * message,	/* message to send           */
		    char *host,	/* proposed destination host */
		    int port,	/* proposed destination port */
		    int socket)	/* proposed socket (if any)  */
{
  size_t length;
  int i;
  char *buf;
  int sock;
  struct addrinfo *addrinfo;
  struct sockaddr_storage addr;

  if (ctx == NULL)
    return -1;

  i = osip_message_to_str (message, &buf, &length);

  if (i != 0)
    return -1;
#ifndef HIDE_MESSAGE
  OSIP_TRACE (osip_trace
	      (__FILE__, __LINE__, OSIP_INFO1, NULL, "\n%s\n", buf));
#endif
  /* For RESPONSE, oSIP ALWAYS provide host and port from the top via */
  /* For REQUEST,  oSIP SOMETIMES provide host and port to use which
     may be different from the request uri */

  if (host == NULL)
    {				/* when host is NULL, we use the request uri value */
      host = message->req_uri->host;
      if (message->req_uri->port != NULL)
	port = osip_atoi (message->req_uri->port);
      else
	port = 5060;
    }

  i = ppl_dns_get_addrinfo(&addrinfo, host, port);
  if (i!=PPL_SUCCESS)
    {
      osip_free (buf);
      return -1;
    }
#if 0
  memcpy (&addr, addrinfo->ai_addr, addrinfo->ai_addrlen);
  freeaddrinfo (addrinfo);
#endif

  /* #define SUPPORT_ICMP */
#ifdef SUPPORT_ICMP
  sock = 0; /* use the default */
  if (transaction!=NULL)
  {
    if (MSG_IS_ACK(message))
      {
	if (transaction->out_socket!=0 && transaction->out_socket!=-1)
	  {
	    ppl_socket_close(transaction->out_socket);
	    transaction->out_socket = 0;
	  }
      }
    if (MSG_IS_REQUEST(message))
      {
	if (transaction->out_socket==0 || transaction->out_socket==-1)
	  transaction->out_socket = udp_plugin_get_new_socket(&addr);
	if (transaction->out_socket==0 || transaction->out_socket==-1) /* use default for ACK */
	  transaction->out_socket = 0;
      }
  }

  /* connect(sock,(struct sockaddr *) &addr,sizeof(addr)); */
#endif

#ifdef SUPPORT_ICMP
  if (MSG_IS_RESPONSE(message)
      || MSG_IS_ACK(message)
      || transaction->out_socket==0)
    i = sendto (ctx->out_socket, (const void *) buf, length, 0,
		(struct sockaddr *) &addr, sizeof (addr));
  else
    i = send (transaction->out_socket, (const void *) buf, length, 0);
  
#else
  sock = ctx->out_socket;
  i = sendto (sock, (const void *) buf, length, 0,
	      addrinfo->ai_addr, addrinfo->ai_addrlen);
  /*(struct sockaddr *) &addr, sizeof (addr)); */
  freeaddrinfo (addrinfo);
#endif
  if (0 > i)
    {
      osip_free (buf);
#ifdef WIN32
      i = WSAGetLastError ();
      if (WSAECONNREFUSED == i)
	{
	  OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
				  "SIP_ECONNREFUSED - No remote server.\n"));
	  return 1;		/* I prefer to answer 1 by now..
				   we'll see later what's better */
	}
#else
      i = errno;
      if (ECONNREFUSED == i)
	{
	  OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
				  "SIP_ECONNREFUSED - No remote server.\n"));
	  return 1;		/* I prefer to answer 1 by now..
				   we'll see later what's better */
	}
#endif
#ifdef WIN32
      OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			      "SIP_NETWORK_ERROR - Network error %i sending message to %s on port %i.\n",
			      i, host, port));
#else
      /* XXX use some configure magic to detect if we have the right strerror_r()
       * function (the one that returns int, not char *) and then use strerror_r()
       * instead.
       */
      OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			      "SIP_NETWORK_ERROR - Network error %i (%s) sending message to %s on port %i.\n",
			      i, strerror (i), host, port));
#endif
      /* SIP_NETWORK_ERROR; */
      return -1;
    }

#ifdef WIN32
  i = WSAGetLastError ();
  if (WSAECONNREFUSED == i)
    {
      OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			      "SIP_ECONNREFUSED - No remote server.\n"));
      return 1;
    }
  if (WSAECONNRESET == i)
    {
      OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			      "SIP_ECONNREFUSED - No remote server.\n"));
      return 1;
    }
  OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_ERROR, NULL,
			  "WSAGetLastError returned : %i.\n", i));
#endif

  OSIP_TRACE (osip_trace
	      (__FILE__, __LINE__, OSIP_INFO1, NULL,
	       "udp_plugin: message sent to %s on port %i\n", host, port));

  osip_free (buf);
  return 0;
}