filter.c

用于linux环境下的SIP服务器

#endif
      /* reject this too long field */
      if (pmatch[i].rm_eo-pmatch[i].rm_so+1>255)
	{
	  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_ERROR,NULL,
				"filter plugin: url component is too long, I choose to reject it!\n"));
	  osip_free(url);
	  return -1;
	}
#ifdef WIN32
      if (i==1)
	_snprintf(match1, pmatch[i].rm_eo-pmatch[i].rm_so, /* -1 with TRE? */
		 "%s", url+pmatch[i].rm_so);
      else if (i==2)
	_snprintf(match2, pmatch[i].rm_eo-pmatch[i].rm_so, /* -1 with TRE? */
		 "%s", url+pmatch[i].rm_so);
#else
      if (i==1)
	snprintf(match1, pmatch[i].rm_eo-pmatch[i].rm_so+1,
		 "%s", url+pmatch[i].rm_so);
      else if (i==2)
	snprintf(match2, pmatch[i].rm_eo-pmatch[i].rm_so+1,
		 "%s", url+pmatch[i].rm_so);
#endif
    }
#ifdef FILTER_TEST
  fprintf(stdout, "match1: %s, match2: %s\n", match1, match2);
#endif
  osip_free(url);
  return 0;
}


static int
filter_build_dnsresult(tel_rule_t *tel_rule, osip_uri_t *req_uri, char *match1,
		       char *match2, char **dest)
{
  char *tmp;
  char *_tmp;
  char *_tmp2;
  *dest = NULL;

  if (req_uri->scheme==NULL)
    /* just in case */
    req_uri->scheme=osip_strdup("sip");
  
  /* find %1 in string */
  _tmp = strstr(tel_rule->dnsresult, "%1");
  /* find %2 in string */
  _tmp2 = strstr(tel_rule->dnsresult, "%2");

  /* this is always enough: (and match1 and match2 can be empty string '\0') */
  tmp = osip_malloc(strlen(tel_rule->dnsresult)
		+strlen(match1)+strlen(match2) + 3 );
  
  if (_tmp!=NULL) /* contains %s */
    {
      /* copy from the beginning to '%1' */
      osip_strncpy(tmp,tel_rule->dnsresult, _tmp-tel_rule->dnsresult);
      /* copy match1 from the current pos end of match1 */
      osip_strncpy(tmp + strlen(tmp), match1, strlen(match1));
      if (_tmp2==NULL) /* simple case */
	/* copy the rest up to the end */
	  osip_strncpy(tmp + strlen(tmp), _tmp+2, strlen(_tmp+2));
      else
	{
	  /* copy the rest up to %2 */
	  osip_strncpy(tmp + strlen(tmp), _tmp+2, _tmp2-_tmp-2);
	  /* copy match2 from the current pos end of match2 */
	  osip_strncpy(tmp + strlen(tmp), match2, strlen(match2));
	  /* copy the rest up to the end */
	  osip_strncpy(tmp + strlen(tmp), _tmp2+2, strlen(_tmp2+2));
	}
    }
  else if (_tmp2!=NULL)
    {
      /* copy from the beginning to '%2' */
      osip_strncpy(tmp,tel_rule->dnsresult, _tmp2-tel_rule->dnsresult);
      /* copy match1 from the current pos end of match2 */
      osip_strncpy(tmp + strlen(tmp), match2, strlen(match2));
      /* copy the rest up to the end */
      osip_strncpy(tmp + strlen(tmp), _tmp2+2, strlen(_tmp2+2));
    }
  else
    sprintf(tmp, tel_rule->dnsresult);

  if (tmp!=NULL)
    {
      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO4,NULL,
			    "filter plugin: Here is the resulted value: %s\n",
			    tmp));
    }

  *dest = tmp;
  return 0;
}

#endif

/* HOOK METHODS */

/*
  This method returns:
  -2 if plugin consider this request should be totally discarded!
  -1 on error
  0  nothing has been done
  1  things has been done on psp_req element
*/
int cb_filter_search_location(psp_request_t *psp_req)
{
#if defined(WIN32) && !defined(TRE)
  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO4,NULL,
	   "filter plugin: not implemented on WIN32\n"));
  psp_request_set_state(psp_req, PSP_PROPOSE);
  psp_request_set_uas_status(psp_req, 404);
  psp_request_set_mode(psp_req, PSP_UAS_MODE);
  return 0;
#else
  tel_rule_t *tel_rule;
  location_t *loc;
  osip_route_t *route;
  osip_uri_t *url;
  int i;
  osip_uri_param_t *psp_param;
  osip_message_t *request;
  request = psp_request_get_request(psp_req);

  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
			"filter plugin: filter_context %p!\n", filter_context));


  if (ISSET_INTERNAL_FILTERSCOPE(filter_context->flag))
    {
      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
		  "filter plugin: configured to process url for local domain!\n"));
    }

  if (ISSET_EXTERNAL_FILTERSCOPE(filter_context->flag))
    {
      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
		  "filter plugin: configured to process url for non local domain!\n"));
    }

  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
	   "filter plugin: entering cb_filter_search_location\n"));

		/* default OUTPUT */
  if (ISSET_R_ROUTE_MODE(filter_context->flag))
    psp_request_set_property(psp_req, PSP_STAY_ON_PATH);
  else
    psp_request_set_property(psp_req, 0);

  if (!ISSET_REDIRECT_MODE(filter_context->flag))
    /* state full or default mode */
    psp_request_set_mode(psp_req, PSP_SFULL_MODE);
  else
    {
      psp_request_set_uas_status(psp_req, 302);
      psp_request_set_mode(psp_req, PSP_UAS_MODE);
    }

  i=0;
  for (;!osip_list_eol(request->routes, i);i++)
    {
      osip_message_get_route (request, i, &route);
      if (0 != psp_core_is_responsible_for_this_route(route->url))
	{
	  psp_request_set_mode (psp_req, PSP_SFULL_MODE);
	  psp_request_set_state (psp_req, PSP_MANDATE);
	  OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_INFO1, NULL,
				  "filter plugin: mandate statefull handling for route.\n"));
	  return 0;
	}
    }

  psp_request_set_state(psp_req, PSP_MANDATE);

  if (i>1)
    {
      psp_request_set_uas_status(psp_req, 482); /* loop? */
      psp_request_set_mode(psp_req, PSP_UAS_MODE);
      return 0;
    }
  if (i==1)
    {
      osip_message_get_route(request, 0, &route); /* should be the first one */
      /* if this route header contains the "psp" parameter, it means
	 the element does not come from a pre-route-set header (in this
	 last case, we want to execute the plugin for the initial request) */
      /* NON compliant UAs (not returning this parameter) are guilty. */
      osip_uri_uparam_get_byname (route->url, "psp", &psp_param);
      if (psp_param!=NULL)
	{
	  psp_request_set_state(psp_req, PSP_MANDATE);
	  psp_request_set_mode (psp_req, PSP_SFULL_MODE);
	  /* got it, leave this plugin. */
	  return 0;
	}
    }

  if (ISSET_INTERNAL_FILTERSCOPE(filter_context->flag)
      && ISSET_EXTERNAL_FILTERSCOPE(filter_context->flag))
    { /* process request in all cases */ }
  else
    {
      if (0 == psp_core_is_responsible_for_this_domain (request->
							req_uri))
	{
	  if (!ISSET_INTERNAL_FILTERSCOPE(filter_context->flag))
	    {
	      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
				    "filter plugin: uri is for our local domain -> do not process it!\n"));
	      psp_request_set_state(psp_req, PSP_PROPOSE);
	      psp_request_set_uas_status(psp_req, 404);
	      psp_request_set_mode(psp_req, PSP_UAS_MODE);
	      return 0;
	    }
	}
      else
	{
	  if (!ISSET_EXTERNAL_FILTERSCOPE(filter_context->flag))
	    {
	      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
				    "filter plugin: uri is not for our local domain -> do not process it!\n"));
	      psp_request_set_state(psp_req, PSP_PROPOSE);
	      psp_request_set_uas_status(psp_req, 404);
	      psp_request_set_mode(psp_req, PSP_UAS_MODE);
	      return 0;
	    }
	}
    }
    

  for (tel_rule = filter_context->tel_rules;
       tel_rule!=NULL;
       tel_rule=tel_rule->next)
    {
      char match1[256];
      char match2[256];
      /* Add this for TRE */
      memset(match1, 0, sizeof(match1));
      memset(match2, 0, sizeof(match2));
      i = filter_match_rule(tel_rule, request, match1, match2);
      if (i!=-1)
	{
	  char *tmp;
	  filter_build_dnsresult(tel_rule, request->req_uri,
				   match1, match2, &tmp);
	  if (tmp==NULL)
	    {
	      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_ERROR,NULL,
				    "filter plugin: failed to build new destination url!\n"));
	      psp_request_set_uas_status(psp_req, 400);
	      psp_request_set_mode(psp_req, PSP_UAS_MODE);
	      psp_request_set_state(psp_req, PSP_MANDATE);
	      return -1;
	    }

	  i = osip_uri_init(&url);
	  i = osip_uri_parse(url, tmp);
	  osip_free(tmp);
	  if (i!=0)
	    {
	      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_ERROR,NULL,
				    "filter plugin: Could not clone request-uri!\n"));
	      psp_request_set_uas_status(psp_req, 400);
	      psp_request_set_mode(psp_req, PSP_UAS_MODE);
	      psp_request_set_state(psp_req, PSP_MANDATE);
	      osip_uri_free(url);
	      return -1;
	    }

	  i = location_init(&loc, url, 3600);
	  if (i!=0)
	    { /* This can only happen in case we don't have enough memory */
	      osip_uri_free(url);
	      OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_BUG,NULL,
				    "filter plugin: Could not create location info!\n"));
	      psp_request_set_uas_status(psp_req, 400);
	      psp_request_set_mode(psp_req, PSP_UAS_MODE);
	      psp_request_set_state(psp_req, PSP_MANDATE);
	      return -1;
	    }
	  ADD_ELEMENT(psp_req->locations, loc);
	  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
				"filter plugin: mandate statefull (or redirect) mode for request.\n"));
	  return 0;
	}
    }

  OSIP_TRACE(osip_trace(__FILE__,__LINE__,OSIP_INFO1,NULL,
	"filter plugin: Didn't do anything with this request?\n"));
  psp_request_set_state(psp_req, PSP_PROPOSE);
  psp_request_set_uas_status(psp_req, 404);
  psp_request_set_mode(psp_req, PSP_UAS_MODE);

  return 0;
#endif
}