Example #1
0
static void dump_answer(unsigned index, const pj_dns_parsed_rr *rr)
{
    const pj_str_t root_name = { "<Root>", 6 };
    const pj_str_t *name = &rr->name;
    char ttl_words[32];

    if (name->slen == 0)
	name = &root_name;

    PJ_LOG(3,(THIS_FILE, " %d. %s record (type=%d)", 
			 index, pj_dns_get_type_name(rr->type),
			rr->type));
    PJ_LOG(3,(THIS_FILE, "    Name: %.*s", (int)name->slen, name->ptr));
    PJ_LOG(3,(THIS_FILE, "    TTL: %u (%s)", rr->ttl, 
			  spell_ttl(ttl_words, sizeof(ttl_words), rr->ttl)));
    PJ_LOG(3,(THIS_FILE, "    Data length: %u", rr->rdlength));

    if (rr->type == PJ_DNS_TYPE_SRV) {
	PJ_LOG(3,(THIS_FILE, "    SRV: prio=%d, weight=%d %.*s:%d", 
			     rr->rdata.srv.prio, rr->rdata.srv.weight,
			     (int)rr->rdata.srv.target.slen, 
			     rr->rdata.srv.target.ptr,
			     rr->rdata.srv.port));
    } else if (rr->type == PJ_DNS_TYPE_CNAME ||
	       rr->type == PJ_DNS_TYPE_NS ||
	       rr->type == PJ_DNS_TYPE_PTR) 
    {
	PJ_LOG(3,(THIS_FILE, "    Name: %.*s",
		  (int)rr->rdata.cname.name.slen,
		  rr->rdata.cname.name.ptr));
    } else if (rr->type == PJ_DNS_TYPE_A) {
	PJ_LOG(3,(THIS_FILE, "    IP address: %s",
		  pj_inet_ntoa(rr->rdata.a.ip_addr)));
    }
}
Example #2
0
static void dump_query(unsigned index, const pj_dns_parsed_query *q)
{
    PJ_LOG(3,(THIS_FILE, " %d. Name: %.*s",
              index, (int)q->name.slen, q->name.ptr));
    PJ_LOG(3,(THIS_FILE, "    Type: %s (%d)",
              pj_dns_get_type_name(q->type), q->type));
    PJ_LOG(3,(THIS_FILE, "    Class: %s (%d)",
              (q->dnsclass==1 ? "IN" : "<Unknown>"), q->dnsclass));
}
Example #3
0
/*
 * The public API to invoke DNS SRV resolution.
 */
PJ_DEF(pj_status_t) pj_dns_srv_resolve( const pj_str_t *domain_name,
				        const pj_str_t *res_name,
					unsigned def_port,
					pj_pool_t *pool,
					pj_dns_resolver *resolver,
					unsigned option,
					void *token,
					pj_dns_srv_resolver_cb *cb,
					pj_dns_srv_async_query **p_query)
{
    pj_size_t len;
    pj_str_t target_name;
    pj_dns_srv_async_query *query_job;
    pj_status_t status;

    PJ_ASSERT_RETURN(domain_name && domain_name->slen &&
		     res_name && res_name->slen &&
		     pool && resolver && cb, PJ_EINVAL);

    /* Build full name */
    len = domain_name->slen + res_name->slen + 2;
    target_name.ptr = (char*) pj_pool_alloc(pool, len);
    pj_strcpy(&target_name, res_name);
    if (res_name->ptr[res_name->slen-1] != '.')
	pj_strcat2(&target_name, ".");
    len = target_name.slen;
    pj_strcat(&target_name, domain_name);
    target_name.ptr[target_name.slen] = '\0';


    /* Build the query_job state */
    query_job = PJ_POOL_ZALLOC_T(pool, pj_dns_srv_async_query);
    query_job->common.type = PJ_DNS_TYPE_SRV;
    query_job->objname = target_name.ptr;
    query_job->resolver = resolver;
    query_job->token = token;
    query_job->cb = cb;
    query_job->option = option;
    query_job->full_name = target_name;
    query_job->domain_part.ptr = target_name.ptr + len;
    query_job->domain_part.slen = target_name.slen - len;
    query_job->def_port = (pj_uint16_t)def_port;

    /* Start the asynchronous query_job */

    query_job->dns_state = PJ_DNS_TYPE_SRV;

    PJ_LOG(5, (query_job->objname, 
	       "Starting async DNS %s query_job: target=%.*s:%d",
	       pj_dns_get_type_name(query_job->dns_state),
	       (int)target_name.slen, target_name.ptr,
	       def_port));

    status = pj_dns_resolver_start_query(resolver, &target_name, 
				         query_job->dns_state, 0, 
					 &dns_callback,
    					 query_job, &query_job->q_srv);
    if (status==PJ_SUCCESS && p_query)
	*p_query = query_job;

    return status;
}
Example #4
0
/*
 * This is the main function for performing server resolution.
 */
PJ_DEF(void) pjsip_resolve( pjsip_resolver_t *resolver,
			    pj_pool_t *pool,
			    const pjsip_host_info *target,
			    void *token,
			    pjsip_resolver_callback *cb)
{
    pjsip_server_addresses svr_addr;
    pj_status_t status = PJ_SUCCESS;
    int ip_addr_ver;
    struct query *query;
    pjsip_transport_type_e type = target->type;

    /* Is it IP address or hostname? And if it's an IP, which version? */
    ip_addr_ver = get_ip_addr_ver(&target->addr.host);

    /* Set the transport type if not explicitly specified. 
     * RFC 3263 section 4.1 specify rules to set up this.
     */
    if (type == PJSIP_TRANSPORT_UNSPECIFIED) {
	if (ip_addr_ver || (target->addr.port != 0)) {
#if PJ_HAS_TCP
	    if (target->flag & PJSIP_TRANSPORT_SECURE) 
	    {
		type = PJSIP_TRANSPORT_TLS;
	    } else if (target->flag & PJSIP_TRANSPORT_RELIABLE) 
	    {
		type = PJSIP_TRANSPORT_TCP;
	    } else 
#endif
	    {
		type = PJSIP_TRANSPORT_UDP;
	    }
	} else {
	    /* No type or explicit port is specified, and the address is
	     * not IP address.
	     * In this case, full NAPTR resolution must be performed.
	     * But we don't support it (yet).
	     */
#if PJ_HAS_TCP
	    if (target->flag & PJSIP_TRANSPORT_SECURE) 
	    {
		type = PJSIP_TRANSPORT_TLS;
	    } else if (target->flag & PJSIP_TRANSPORT_RELIABLE) 
	    {
		type = PJSIP_TRANSPORT_TCP;
	    } else 
#endif
	    {
		type = PJSIP_TRANSPORT_UDP;
	    }
	}

	/* Add IPv6 flag for IPv6 address */
	if (ip_addr_ver == 6)
	    type = (pjsip_transport_type_e)((int)type + PJSIP_TRANSPORT_IPV6);
    }


    /* If target is an IP address, or if resolver is not configured, 
     * we can just finish the resolution now using pj_gethostbyname()
     */
    if (ip_addr_ver || resolver->res == NULL) {
	char addr_str[PJ_INET6_ADDRSTRLEN+10];
	pj_uint16_t srv_port;

	if (ip_addr_ver != 0) {
	    /* Target is an IP address, no need to resolve */
	    if (ip_addr_ver == 4) {
		pj_sockaddr_init(pj_AF_INET(), &svr_addr.entry[0].addr, 
				 NULL, 0);
		pj_inet_aton(&target->addr.host,
			     &svr_addr.entry[0].addr.ipv4.sin_addr);
	    } else {
		pj_sockaddr_init(pj_AF_INET6(), &svr_addr.entry[0].addr, 
				 NULL, 0);
		pj_inet_pton(pj_AF_INET6(), &target->addr.host,
			     &svr_addr.entry[0].addr.ipv6.sin6_addr);
	    }
	} else {
	    pj_addrinfo ai;
	    unsigned count;
	    int af;

	    PJ_LOG(5,(THIS_FILE,
		      "DNS resolver not available, target '%.*s:%d' type=%s "
		      "will be resolved with getaddrinfo()",
		      target->addr.host.slen,
		      target->addr.host.ptr,
		      target->addr.port,
		      pjsip_transport_get_type_name(target->type)));

	    if (type & PJSIP_TRANSPORT_IPV6) {
		af = pj_AF_INET6();
	    } else {
		af = pj_AF_INET();
	    }

	    /* Resolve */
	    count = 1;
	    status = pj_getaddrinfo(af, &target->addr.host, &count, &ai);
	    if (status != PJ_SUCCESS)
		goto on_error;

	    svr_addr.entry[0].addr.addr.sa_family = (pj_uint16_t)af;
	    pj_memcpy(&svr_addr.entry[0].addr, &ai.ai_addr,
		      sizeof(pj_sockaddr));
	}

	/* Set the port number */
	if (target->addr.port == 0) {
	   srv_port = (pj_uint16_t)
		      pjsip_transport_get_default_port_for_type(type);
	} else {
	   srv_port = (pj_uint16_t)target->addr.port;
	}
	pj_sockaddr_set_port(&svr_addr.entry[0].addr, srv_port);

	/* Call the callback. */
	PJ_LOG(5,(THIS_FILE, 
		  "Target '%.*s:%d' type=%s resolved to "
		  "'%s' type=%s (%s)",
		  (int)target->addr.host.slen,
		  target->addr.host.ptr,
		  target->addr.port,
		  pjsip_transport_get_type_name(target->type),
		  pj_sockaddr_print(&svr_addr.entry[0].addr, addr_str,
				    sizeof(addr_str), 3),
		  pjsip_transport_get_type_name(type),
		  pjsip_transport_get_type_desc(type)));
	svr_addr.count = 1;
	svr_addr.entry[0].priority = 0;
	svr_addr.entry[0].weight = 0;
	svr_addr.entry[0].type = type;
	svr_addr.entry[0].addr_len = pj_sockaddr_get_len(&svr_addr.entry[0].addr);
	(*cb)(status, token, &svr_addr);

	/* Done. */
	return;
    }

    /* Target is not an IP address so we need to resolve it. */
#if PJSIP_HAS_RESOLVER

    /* Build the query state */
    query = PJ_POOL_ZALLOC_T(pool, struct query);
    query->objname = THIS_FILE;
    query->token = token;
    query->cb = cb;
    query->req.target = *target;
    pj_strdup(pool, &query->req.target.addr.host, &target->addr.host);

    /* If port is not specified, start with SRV resolution
     * (should be with NAPTR, but we'll do that later)
     */
    PJ_TODO(SUPPORT_DNS_NAPTR);

    /* Build dummy NAPTR entry */
    query->naptr_cnt = 1;
    pj_bzero(&query->naptr[0], sizeof(query->naptr[0]));
    query->naptr[0].order = 0;
    query->naptr[0].pref = 0;
    query->naptr[0].type = type;
    pj_strdup(pool, &query->naptr[0].name, &target->addr.host);


    /* Start DNS SRV or A resolution, depending on whether port is specified */
    if (target->addr.port == 0) {
	query->query_type = PJ_DNS_TYPE_SRV;

	query->req.def_port = 5060;

	if (type == PJSIP_TRANSPORT_TLS) {
	    query->naptr[0].res_type = pj_str("_sips._tcp.");
	    query->req.def_port = 5061;
	} else if (type == PJSIP_TRANSPORT_TCP)
	    query->naptr[0].res_type = pj_str("_sip._tcp.");
	else if (type == PJSIP_TRANSPORT_UDP)
	    query->naptr[0].res_type = pj_str("_sip._udp.");
	else {
	    pj_assert(!"Unknown transport type");
	    query->naptr[0].res_type = pj_str("_sip._udp.");
	    
	}

    } else {
	/* Otherwise if port is specified, start with A (or AAAA) host 
	 * resolution 
	 */
	query->query_type = PJ_DNS_TYPE_A;
	query->naptr[0].res_type.slen = 0;
	query->req.def_port = target->addr.port;
    }

    /* Start the asynchronous query */
    PJ_LOG(5, (query->objname, 
	       "Starting async DNS %s query: target=%.*s%.*s, transport=%s, "
	       "port=%d",
	       pj_dns_get_type_name(query->query_type),
	       (int)query->naptr[0].res_type.slen,
	       query->naptr[0].res_type.ptr,
	       (int)query->naptr[0].name.slen, query->naptr[0].name.ptr,
	       pjsip_transport_get_type_name(target->type),
	       target->addr.port));

    if (query->query_type == PJ_DNS_TYPE_SRV) {

    		unsigned option = PJ_TRUE;
    	        if (type & PJSIP_TRANSPORT_IPV6) {
    	            option |= PJ_DNS_SRV_FALLBACK_GETADDRINFO_IPV6;
    	        } else {
    	            option |= PJ_DNS_SRV_FALLBACK_GETADDRINFO_IPV4;
    	        }

    	        status = pj_dns_srv_resolve(&query->naptr[0].name,
    	        			    &query->naptr[0].res_type,
    	        			    query->req.def_port, pool, resolver->res,
    	        			    option, query, &srv_resolver_cb, NULL);

    } else if (query->query_type == PJ_DNS_TYPE_A) {

    	 status = pj_dns_resolver_start_query(resolver->res,
					     &query->naptr[0].name,
					     PJ_DNS_TYPE_A, 0, 
					     &dns_a_callback,
    					     query, &query->object);

    } else {
	pj_assert(!"Unexpected");
	status = PJ_EBUG;
    }

    if (status != PJ_SUCCESS)
	goto on_error;

    return;

#else /* PJSIP_HAS_RESOLVER */
    PJ_UNUSED_ARG(pool);
    PJ_UNUSED_ARG(query);
    PJ_UNUSED_ARG(srv_name);
#endif /* PJSIP_HAS_RESOLVER */

on_error:
    if (status != PJ_SUCCESS) {
	char errmsg[PJ_ERR_MSG_SIZE];
	PJ_LOG(4,(THIS_FILE, "Failed to resolve '%.*s'. Err=%d (%s)",
			     (int)target->addr.host.slen,
			     target->addr.host.ptr,
			     status,
			     pj_strerror(status,errmsg,sizeof(errmsg)).ptr));
	(*cb)(status, token, NULL);
	return;
    }
}
Example #5
0
/*
 * This is the main function for performing server resolution.
 */
PJ_DEF(void) pjsip_resolve( pjsip_resolver_t *resolver,
			    pj_pool_t *pool,
			    const pjsip_host_info *target,
			    void *token,
			    pjsip_resolver_callback *cb)
{
    pjsip_server_addresses svr_addr;
    pj_status_t status = PJ_SUCCESS;
    int ip_addr_ver;
    struct query *query;
    pjsip_transport_type_e type = target->type;
    int af = pj_AF_UNSPEC();

    /* If an external implementation has been provided use it instead */
    if (resolver->ext_res) {
        (*resolver->ext_res->resolve)(resolver, pool, target, token, cb);
        return;
    }

    /* Is it IP address or hostname? And if it's an IP, which version? */
    ip_addr_ver = get_ip_addr_ver(&target->addr.host);

    /* Initialize address family type. Unfortunately, target type doesn't
     * really tell the address family type, except when IPv6 flag is
     * explicitly set.
     */
#if defined(PJ_HAS_IPV6) && PJ_HAS_IPV6==1
    if ((ip_addr_ver == 6) || (type & PJSIP_TRANSPORT_IPV6))
	af = pj_AF_INET6();
    else if (ip_addr_ver == 4)
	af = pj_AF_INET();
#else
    /* IPv6 is disabled, will resolving IPv6 address be useful? */
    af = pj_AF_INET();
#endif

    /* Set the transport type if not explicitly specified. 
     * RFC 3263 section 4.1 specify rules to set up this.
     */
    if (type == PJSIP_TRANSPORT_UNSPECIFIED) {
	if (ip_addr_ver || (target->addr.port != 0)) {
#if PJ_HAS_TCP
	    if (target->flag & PJSIP_TRANSPORT_SECURE) 
	    {
		type = PJSIP_TRANSPORT_TLS;
	    } else if (target->flag & PJSIP_TRANSPORT_RELIABLE) 
	    {
		type = PJSIP_TRANSPORT_TCP;
	    } else 
#endif
	    {
		type = PJSIP_TRANSPORT_UDP;
	    }
	} else {
	    /* No type or explicit port is specified, and the address is
	     * not IP address.
	     * In this case, full NAPTR resolution must be performed.
	     * But we don't support it (yet).
	     */
#if PJ_HAS_TCP
	    if (target->flag & PJSIP_TRANSPORT_SECURE) 
	    {
		type = PJSIP_TRANSPORT_TLS;
	    } else if (target->flag & PJSIP_TRANSPORT_RELIABLE) 
	    {
		type = PJSIP_TRANSPORT_TCP;
	    } else 
#endif
	    {
		type = PJSIP_TRANSPORT_UDP;
	    }
	}
    }


    /* If target is an IP address, or if resolver is not configured, 
     * we can just finish the resolution now using pj_gethostbyname()
     */
    if (ip_addr_ver || resolver->res == NULL) {
	char addr_str[PJ_INET6_ADDRSTRLEN+10];
	pj_uint16_t srv_port;

	if (ip_addr_ver != 0) {
	    /* Target is an IP address, no need to resolve */
	    if (ip_addr_ver == 4) {
		pj_sockaddr_init(pj_AF_INET(), &svr_addr.entry[0].addr, 
				 NULL, 0);
		pj_inet_pton(pj_AF_INET(), &target->addr.host,
			     &svr_addr.entry[0].addr.ipv4.sin_addr);
	    } else {
		pj_sockaddr_init(pj_AF_INET6(), &svr_addr.entry[0].addr, 
				 NULL, 0);
		pj_inet_pton(pj_AF_INET6(), &target->addr.host,
			     &svr_addr.entry[0].addr.ipv6.sin6_addr);
	    }
	} else {
	    pj_addrinfo ai;
	    unsigned count;

	    PJ_LOG(5,(THIS_FILE,
		      "DNS resolver not available, target '%.*s:%d' type=%s "
		      "will be resolved with getaddrinfo()",
		      target->addr.host.slen,
		      target->addr.host.ptr,
		      target->addr.port,
		      pjsip_transport_get_type_name(target->type)));

	    /* Resolve */
	    count = 1;
	    status = pj_getaddrinfo(af, &target->addr.host, &count, &ai);
	    if (status != PJ_SUCCESS) {
		/* "Normalize" error to PJ_ERESOLVE. This is a special error
		 * because it will be translated to SIP status 502 by
		 * sip_transaction.c
		 */
		status = PJ_ERESOLVE;
		goto on_error;
	    }

	    pj_sockaddr_cp(&svr_addr.entry[0].addr, &ai.ai_addr);
	    if (af == pj_AF_UNSPEC())
		af = ai.ai_addr.addr.sa_family;
	}

	/* After address resolution, update IPv6 bitflag in transport type. */
	if (af == pj_AF_INET6())
	    type |= PJSIP_TRANSPORT_IPV6;

	/* Set the port number */
	if (target->addr.port == 0) {
	   srv_port = (pj_uint16_t)
		      pjsip_transport_get_default_port_for_type(type);
	} else {
	   srv_port = (pj_uint16_t)target->addr.port;
	}
	pj_sockaddr_set_port(&svr_addr.entry[0].addr, srv_port);

	/* Call the callback. */
	PJ_LOG(5,(THIS_FILE, 
		  "Target '%.*s:%d' type=%s resolved to "
		  "'%s' type=%s (%s)",
		  (int)target->addr.host.slen,
		  target->addr.host.ptr,
		  target->addr.port,
		  pjsip_transport_get_type_name(target->type),
		  pj_sockaddr_print(&svr_addr.entry[0].addr, addr_str,
				    sizeof(addr_str), 3),
		  pjsip_transport_get_type_name(type),
		  pjsip_transport_get_type_desc(type)));
	svr_addr.count = 1;
	svr_addr.entry[0].priority = 0;
	svr_addr.entry[0].weight = 0;
	svr_addr.entry[0].type = type;
	svr_addr.entry[0].addr_len = 
				pj_sockaddr_get_len(&svr_addr.entry[0].addr);
	(*cb)(status, token, &svr_addr);

	/* Done. */
	return;
    }

    /* Target is not an IP address so we need to resolve it. */
#if PJSIP_HAS_RESOLVER

    /* Build the query state */
    query = PJ_POOL_ZALLOC_T(pool, struct query);
    query->objname = THIS_FILE;
    query->token = token;
    query->cb = cb;
    query->req.target = *target;
    pj_strdup(pool, &query->req.target.addr.host, &target->addr.host);

    /* If port is not specified, start with SRV resolution
     * (should be with NAPTR, but we'll do that later)
     */
    PJ_TODO(SUPPORT_DNS_NAPTR);

    /* Build dummy NAPTR entry */
    query->naptr_cnt = 1;
    pj_bzero(&query->naptr[0], sizeof(query->naptr[0]));
    query->naptr[0].order = 0;
    query->naptr[0].pref = 0;
    query->naptr[0].type = type;
    pj_strdup(pool, &query->naptr[0].name, &target->addr.host);


    /* Start DNS SRV or A resolution, depending on whether port is specified */
    if (target->addr.port == 0) {
	query->query_type = PJ_DNS_TYPE_SRV;

	query->req.def_port = 5060;

	if (type == PJSIP_TRANSPORT_TLS || type == PJSIP_TRANSPORT_TLS6) {
	    query->naptr[0].res_type = pj_str("_sips._tcp.");
	    query->req.def_port = 5061;
	} else if (type == PJSIP_TRANSPORT_TCP || type == PJSIP_TRANSPORT_TCP6)
	    query->naptr[0].res_type = pj_str("_sip._tcp.");
	else if (type == PJSIP_TRANSPORT_UDP || type == PJSIP_TRANSPORT_UDP6)
	    query->naptr[0].res_type = pj_str("_sip._udp.");
	else {
	    pj_assert(!"Unknown transport type");
	    query->naptr[0].res_type = pj_str("_sip._udp.");
	    
	}

    } else {
	/* Otherwise if port is specified, start with A (or AAAA) host 
	 * resolution 
	 */
	query->query_type = PJ_DNS_TYPE_A;
	query->naptr[0].res_type.slen = 0;
	query->req.def_port = target->addr.port;
    }

    /* Start the asynchronous query */
    PJ_LOG(5, (query->objname, 
	       "Starting async DNS %s query: target=%.*s%.*s, transport=%s, "
	       "port=%d",
	       pj_dns_get_type_name(query->query_type),
	       (int)query->naptr[0].res_type.slen,
	       query->naptr[0].res_type.ptr,
	       (int)query->naptr[0].name.slen, query->naptr[0].name.ptr,
	       pjsip_transport_get_type_name(target->type),
	       target->addr.port));

    if (query->query_type == PJ_DNS_TYPE_SRV) {
	int opt = 0;

	if (af == pj_AF_UNSPEC())
	    opt = PJ_DNS_SRV_FALLBACK_A | PJ_DNS_SRV_FALLBACK_AAAA |
		  PJ_DNS_SRV_RESOLVE_AAAA;
	else if (af == pj_AF_INET6())
	    opt = PJ_DNS_SRV_FALLBACK_AAAA | PJ_DNS_SRV_RESOLVE_AAAA_ONLY;
	else /* af == pj_AF_INET() */
	    opt = PJ_DNS_SRV_FALLBACK_A;

	status = pj_dns_srv_resolve(&query->naptr[0].name,
				    &query->naptr[0].res_type,
				    query->req.def_port, pool, resolver->res,
				    opt, query, &srv_resolver_cb, NULL);

    } else if (query->query_type == PJ_DNS_TYPE_A) {

	/* Resolve DNS A record if address family is not fixed to IPv6 */
	if (af != pj_AF_INET6()) {

	    /* If there will be DNS AAAA query too, let's setup a dummy one
	     * here, otherwise app callback may be called immediately (before
	     * DNS AAAA query is sent) when DNS A record is available in the
	     * cache.
	     */
	    if (af == pj_AF_UNSPEC())
		query->object6 = (pj_dns_async_query*)0x1;

	    status = pj_dns_resolver_start_query(resolver->res, 
						 &query->naptr[0].name,
						 PJ_DNS_TYPE_A, 0, 
						 &dns_a_callback,
    						 query, &query->object);
	}

	/* Resolve DNS AAAA record if address family is not fixed to IPv4 */
	if (af != pj_AF_INET() && status == PJ_SUCCESS) {
	    status = pj_dns_resolver_start_query(resolver->res, 
						 &query->naptr[0].name,
						 PJ_DNS_TYPE_AAAA, 0, 
						 &dns_aaaa_callback,
    						 query, &query->object6);
	}

    } else {
	pj_assert(!"Unexpected");
	status = PJ_EBUG;
    }

    if (status != PJ_SUCCESS)
	goto on_error;

    return;

#else /* PJSIP_HAS_RESOLVER */
    PJ_UNUSED_ARG(pool);
    PJ_UNUSED_ARG(query);
    PJ_UNUSED_ARG(srv_name);
#endif /* PJSIP_HAS_RESOLVER */

on_error:
    if (status != PJ_SUCCESS) {
	char errmsg[PJ_ERR_MSG_SIZE];
	PJ_LOG(4,(THIS_FILE, "Failed to resolve '%.*s'. Err=%d (%s)",
			     (int)target->addr.host.slen,
			     target->addr.host.ptr,
			     status,
			     pj_strerror(status,errmsg,sizeof(errmsg)).ptr));
	(*cb)(status, token, NULL);
	return;
    }
}