/*
* SIP_GEN_RESPONSE
*
* send an proxy generated response back to the client.
* Only errors are reported from the proxy itself.
* code = SIP result code to deliver
*
* RETURNS
* STS_SUCCESS on success
* STS_FAILURE on error
*/
int sip_gen_response(sip_ticket_t *ticket, int code) {
osip_message_t *response;
int sts;
osip_via_t *via;
int port;
char *buffer;
size_t buflen;
struct in_addr addr;
/* create the response template */
if ((response=msg_make_template_reply(ticket, code))==NULL) {
ERROR("sip_gen_response: error in msg_make_template_reply");
return STS_FAILURE;
}
/* we must check if first via has x.x.x.x address. If not, we must resolve it */
osip_message_get_via (response, 0, &via);
if (via == NULL)
{
ERROR("sip_gen_response: Cannot send response - no via field");
return STS_FAILURE;
}
/* name resolution */
if (utils_inet_aton(via->host, &addr) == 0)
{
/* need name resolution */
DEBUGC(DBCLASS_DNS,"resolving name:%s",via->host);
sts = get_ip_by_host(via->host, &addr);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "sip_gen_response: cannot resolve via [%s]",
via->host);
return STS_FAILURE;
}
}
sts = sip_message_to_str(response, &buffer, &buflen);
if (sts != 0) {
ERROR("sip_gen_response: msg_2char failed");
return STS_FAILURE;
}
if (via->port) {
port=atoi(via->port);
} else {
port=SIP_PORT;
}
/* send to destination */
sipsock_send(addr, port, ticket->protocol, buffer, buflen);
/* free the resources */
osip_message_free(response);
osip_free(buffer);
return STS_SUCCESS;
}
static int stun_send_request(char *tid){
struct in_addr addr;
int sts;
char stun_rq[28]; /*&&& testing */
size_t size=28;
/* name resolution */
if (utils_inet_aton(plugin_cfg.server, &addr) == 0)
{
/* need name resolution */
DEBUGC(DBCLASS_DNS,"resolving name:%s", plugin_cfg.server);
sts = get_ip_by_host(plugin_cfg.server, &addr);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_DNS, "stun_send_request: cannot resolve STUN server [%s]",
plugin_cfg.server);
return STS_FAILURE;
}
}
/* compose STUN BIND request - poor mans way */
stun_rq[0]=0x00; // type
stun_rq[1]=0x01;
stun_rq[2]=0x00; // length
stun_rq[3]=0x08;
memcpy (&stun_rq[4], tid, STUN_TID_SIZE);
stun_rq[20]=0x00; // ATTR change request
stun_rq[21]=0x03;
stun_rq[22]=0x00; // ATTR len 4
stun_rq[23]=0x04;
stun_rq[24]=0x00; // Change IP not set, Change port not set
stun_rq[25]=0x00;
stun_rq[26]=0x00;
stun_rq[27]=0x00;
/* and send via the SIP UDP port */
sts = sipsock_send(addr, plugin_cfg.port, PROTO_UDP, stun_rq, size);
return STS_SUCCESS;
}
/*
* send answer to a registration request.
* flag = STS_SUCCESS -> positive answer (200)
* flag = STS_FAILURE -> negative answer (503)
* flag = STS_NEED_AUTH -> proxy authentication needed (407)
*
* RETURNS
* STS_SUCCESS on success
* STS_FAILURE on error
*/
int register_response(sip_ticket_t *ticket, int flag) {
osip_message_t *response;
int code;
int sts;
osip_via_t *via;
int port;
char *buffer;
size_t buflen;
struct in_addr addr;
osip_header_t *expires_hdr;
/* ok -> 200, fail -> 503 */
switch (flag) {
case STS_SUCCESS:
code = 200; /* OK */
break;
case STS_FAILURE:
code = 503; /* failed */
break;
case STS_NEED_AUTH:
code = 407; /* proxy authentication needed */
break;
default:
code = 503; /* failed */
break;
}
/* create the response template */
if ((response=msg_make_template_reply(ticket, code))==NULL) {
ERROR("register_response: error in msg_make_template_reply");
return STS_FAILURE;
}
/* insert the expiration header */
osip_message_get_expires(ticket->sipmsg, 0, &expires_hdr);
if (expires_hdr) {
osip_message_set_expires(response, expires_hdr->hvalue);
}
/* if we send back an proxy authentication needed,
include the Proxy-Authenticate field */
if (code == 407) {
auth_include_authrq(response);
}
/* get the IP address from existing VIA header */
osip_message_get_via (response, 0, &via);
if (via == NULL) {
ERROR("register_response: Cannot send response - no via field");
return STS_FAILURE;
}
/* name resolution needed? */
if (utils_inet_aton(via->host,&addr) == 0) {
/* yes, get IP address */
sts = get_ip_by_host(via->host, &addr);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_REG, "register_response: cannot resolve VIA [%s]",
via->host);
return STS_FAILURE;
}
}
sts = sip_message_to_str(response, &buffer, &buflen);
if (sts != 0) {
ERROR("register_response: msg_2char failed");
return STS_FAILURE;
}
/* send answer back */
if (via->port) {
port=atoi(via->port);
if ((port<=0) || (port>65535)) port=SIP_PORT;
} else {
port=configuration.sip_listen_port;
}
sipsock_send(addr, port, ticket->protocol, buffer, buflen);
/* free the resources */
osip_message_free(response);
free(buffer);
return STS_SUCCESS;
}
/*
* PROXY_REQUEST
*
* RETURNS
* STS_SUCCESS on success
* STS_FAILURE on error
*
* RFC3261
* Section 16.3: Proxy Behavior - Request Validation
* 1. Reasonable Syntax
* 2. URI scheme
* 3. Max-Forwards
* 4. (Optional) Loop Detection
* 5. Proxy-Require
* 6. Proxy-Authorization
*
* Section 16.6: Proxy Behavior - Request Forwarding
* 1. Make a copy of the received request
* 2. Update the Request-URI
* 3. Update the Max-Forwards header field
* 4. Optionally add a Record-route header field value
* 5. Optionally add additional header fields
* 6. Postprocess routing information
* 7. Determine the next-hop address, port, and transport
* 8. Add a Via header field value
* 9. Add a Content-Length header field if necessary
* 10. Forward the new request
* 11. Set timer C
*/
int proxy_request (sip_ticket_t *ticket) {
int i;
int sts;
int type;
struct in_addr sendto_addr;
osip_uri_t *url;
int port;
char *buffer;
int buflen;
osip_message_t *request;
struct sockaddr_in *from;
DEBUGC(DBCLASS_PROXY,"proxy_request");
if (ticket==NULL) {
ERROR("proxy_request: called with NULL ticket");
return STS_FAILURE;
}
request=ticket->sipmsg;
from=&ticket->from;
/*
* RFC 3261, Section 16.4
* Proxy Behavior - Route Information Preprocessing
* (process Route header)
*/
route_preprocess(ticket);
/*
* figure out whether this is an incoming or outgoing request
* by doing a lookup in the registration table.
*/
#define _OLD_DIRECTION_EVALUATION 0
#if _OLD_DIRECTION_EVALUATION
type = 0;
for (i=0; i<URLMAP_SIZE; i++) {
if (urlmap[i].active == 0) continue;
/* incoming request ('to' == 'masq') || (('to' == 'reg') && !REGISTER)*/
if ((compare_url(request->to->url, urlmap[i].masq_url)==STS_SUCCESS) ||
(!MSG_IS_REGISTER(request) &&
(compare_url(request->to->url, urlmap[i].reg_url)==STS_SUCCESS))) {
type=REQTYP_INCOMING;
DEBUGC(DBCLASS_PROXY,"incoming request from %s@%s from outbound",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host: "*NULL*");
break;
}
/* outgoing request ('from' == 'reg') */
if (compare_url(request->from->url, urlmap[i].reg_url)==STS_SUCCESS) {
type=REQTYP_OUTGOING;
DEBUGC(DBCLASS_PROXY,"outgoing request from %s@%s from inbound",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host: "*NULL*");
break;
}
}
#else
type = 0;
/*
* did I receive the telegram from a REGISTERED host?
* -> it must be an OUTGOING request
*/
for (i=0; i<URLMAP_SIZE; i++) {
struct in_addr tmp_addr;
if (urlmap[i].active == 0) continue;
if (get_ip_by_host(urlmap[i].true_url->host, &tmp_addr) == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_request: cannot resolve host [%s]",
urlmap[i].true_url);
} else {
DEBUGC(DBCLASS_PROXY, "proxy_request: reghost:%s ip:%s",
urlmap[i].true_url->host, utils_inet_ntoa(from->sin_addr));
if (memcmp(&tmp_addr, &from->sin_addr, sizeof(tmp_addr)) == 0) {
type=REQTYP_OUTGOING;
break;
}
}
}
/*
* is the telegram directed to an internally registered host?
* -> it must be an INCOMING request
*/
if (type == 0) {
for (i=0; i<URLMAP_SIZE; i++) {
if (urlmap[i].active == 0) continue;
/* RFC3261:
* 'To' contains a display name (Bob) and a SIP or SIPS URI
* (sip:[email protected]) towards which the request was originally
* directed. Display names are described in RFC 2822 [3].
*/
/* So this means, that we must check the SIP URI supplied with the
* INVITE method, as this points to the real wanted target.
* Q: does there exist a situation where the SIP URI itself does
* point to "somewhere" but the To: points to the correct UA?
* So for now, we just look at both of them (SIP URI and To: header)
*/
/* incoming request (SIP URI == 'masq') || ((SIP URI == 'reg') && !REGISTER)*/
if ((compare_url(request->req_uri, urlmap[i].masq_url)==STS_SUCCESS) ||
(!MSG_IS_REGISTER(request) &&
(compare_url(request->req_uri, urlmap[i].reg_url)==STS_SUCCESS))) {
type=REQTYP_INCOMING;
break;
}
/* incoming request ('to' == 'masq') || (('to' == 'reg') && !REGISTER)*/
if ((compare_url(request->to->url, urlmap[i].masq_url)==STS_SUCCESS) ||
(!MSG_IS_REGISTER(request) &&
(compare_url(request->to->url, urlmap[i].reg_url)==STS_SUCCESS))) {
type=REQTYP_INCOMING;
break;
}
}
}
#endif
ticket->direction=type;
/*
* logging of passing calls
*/
if (configuration.log_calls) {
osip_uri_t *cont_url = NULL;
if (!osip_list_eol(request->contacts, 0))
cont_url = ((osip_contact_t*)(request->contacts->node->element))->url;
/* INVITE */
if (MSG_IS_INVITE(request)) {
if (cont_url) {
INFO("%s Call from: %s@%s",
(type==REQTYP_INCOMING) ? "Incoming":"Outgoing",
cont_url->username ? cont_url->username:"******",
cont_url->host ? cont_url->host : "*NULL*");
} else {
INFO("%s Call (w/o contact header) from: %s@%s",
(type==REQTYP_INCOMING) ? "Incoming":"Outgoing",
request->from->url->username ?
request->from->url->username:"******",
request->from->url->host ?
request->from->url->host : "*NULL*");
}
/* BYE / CANCEL */
} else if (MSG_IS_BYE(request) || MSG_IS_CANCEL(request)) {
if (cont_url) {
INFO("Ending Call from: %s@%s",
cont_url->username ? cont_url->username:"******",
cont_url->host ? cont_url->host : "*NULL*");
} else {
INFO("Ending Call (w/o contact header) from: %s@%s",
request->from->url->username ?
request->from->url->username:"******",
request->from->url->host ?
request->from->url->host : "*NULL*");
}
}
} /* log_calls */
/*
* RFC 3261, Section 16.6 step 1
* Proxy Behavior - Request Forwarding - Make a copy
*/
/* nothing to do here, copy is ready in 'request'*/
/* get destination address */
url=osip_message_get_uri(request);
switch (type) {
/*
* from an external host to the internal masqueraded host
*/
case REQTYP_INCOMING:
DEBUGC(DBCLASS_PROXY,"incoming request from %s@%s from outbound",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host: "*NULL*");
/*
* RFC 3261, Section 16.6 step 2
* Proxy Behavior - Request Forwarding - Request-URI
* (rewrite request URI to point to the real host)
*/
/* 'i' still holds the valid index into the URLMAP table */
if (check_rewrite_rq_uri(request) == STS_TRUE) {
proxy_rewrite_request_uri(request, i);
}
/* if this is CANCEL/BYE request, stop RTP proxying */
if (MSG_IS_BYE(request) || MSG_IS_CANCEL(request)) {
/* stop the RTP proxying stream(s) */
rtp_stop_fwd(osip_message_get_call_id(request), DIR_INCOMING);
rtp_stop_fwd(osip_message_get_call_id(request), DIR_OUTGOING);
/* check for incoming request */
} else if (MSG_IS_INVITE(request)) {
/* Rewrite the body */
sts = proxy_rewrite_invitation_body(request, DIR_INCOMING);
} else if (MSG_IS_ACK(request)) {
/* Rewrite the body */
sts = proxy_rewrite_invitation_body(request, DIR_INCOMING);
}
break;
/*
* from the internal masqueraded host to an external host
*/
case REQTYP_OUTGOING:
DEBUGC(DBCLASS_PROXY,"outgoing request from %s@%s from inbound",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host: "*NULL*");
/*
* RFC 3261, Section 16.6 step 2
* Proxy Behavior - Request Forwarding - Request-URI
*/
/* nothing to do for an outgoing request */
/* if it is addressed to myself, then it must be some request
* method that I as a proxy do not support. Reject */
#if 0
/* careful - an internal UA might send an request to another internal UA.
This would be caught here, so don't do this. This situation should be
caught in the default part of the CASE statement below */
if (is_sipuri_local(ticket) == STS_TRUE) {
WARN("unsupported request [%s] directed to proxy from %s@%s -> %s@%s",
request->sip_method? request->sip_method:"*NULL*",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host : "*NULL*",
url->username? url->username : "******",
url->host? url->host : "*NULL*");
sip_gen_response(ticket, 403 /*forbidden*/);
return STS_FAILURE;
}
#endif
/* rewrite Contact header to represent the masqued address */
sip_rewrite_contact(ticket, DIR_OUTGOING);
/* if an INVITE, rewrite body */
if (MSG_IS_INVITE(request)) {
sts = proxy_rewrite_invitation_body(request, DIR_OUTGOING);
} else if (MSG_IS_ACK(request)) {
sts = proxy_rewrite_invitation_body(request, DIR_OUTGOING);
}
/* if this is CANCEL/BYE request, stop RTP proxying */
if (MSG_IS_BYE(request) || MSG_IS_CANCEL(request)) {
/* stop the RTP proxying stream(s) */
rtp_stop_fwd(osip_message_get_call_id(request), DIR_INCOMING);
rtp_stop_fwd(osip_message_get_call_id(request), DIR_OUTGOING);
}
break;
default:
DEBUGC(DBCLASS_PROXY, "request [%s] from/to unregistered UA "
"(RQ: %s@%s -> %s@%s)",
request->sip_method? request->sip_method:"*NULL*",
request->from->url->username? request->from->url->username:"******",
request->from->url->host? request->from->url->host : "*NULL*",
url->username? url->username : "******",
url->host? url->host : "*NULL*");
/*
* we may end up here for two reasons:
* 1) An incomming request (from outbound) that is directed to
* an unknown (not registered) local UA
* 2) an outgoing request from a local UA that is not registered.
*
* Case 1) we should probably answer with "404 Not Found",
* case 2) more likely a "403 Forbidden"
*
* How about "408 Request Timeout" ?
*
*/
sip_gen_response(ticket, 408 /* Request Timeout */);
return STS_FAILURE;
}
/*
* RFC 3261, Section 16.6 step 3
* Proxy Behavior - Request Forwarding - Max-Forwards
* (if Max-Forwards header exists, decrement by one, if it does not
* exist, add a new one with value SHOULD be 70)
*/
{
osip_header_t *max_forwards;
int forwards_count = DEFAULT_MAXFWD;
char mfwd[8];
osip_message_get_max_forwards(request, 0, &max_forwards);
if (max_forwards == NULL) {
sprintf(mfwd, "%i", forwards_count);
osip_message_set_max_forwards(request, mfwd);
} else {
if (max_forwards->hvalue) {
forwards_count = atoi(max_forwards->hvalue);
forwards_count -=1;
osip_free (max_forwards->hvalue);
}
sprintf(mfwd, "%i", forwards_count);
max_forwards->hvalue = osip_strdup(mfwd);
}
DEBUGC(DBCLASS_PROXY,"setting Max-Forwards=%s",mfwd);
}
/*
* RFC 3261, Section 16.6 step 4
* Proxy Behavior - Request Forwarding - Add a Record-route header
*/
/*
* for ALL incoming requests, include my Record-Route header.
* The local UA will probably send its answer to the topmost
* Route Header (8.1.2 of RFC3261)
*/
if (type == REQTYP_INCOMING) {
DEBUGC(DBCLASS_PROXY,"Adding my Record-Route");
route_add_recordroute(ticket);
} else {
/*
* outgoing packets must not have my record route header, as
* this likely will contain a private IP address (my inbound).
*/
DEBUGC(DBCLASS_PROXY,"Purging Record-Routes (outgoing packet)");
route_purge_recordroute(ticket);
}
/*
* RFC 3261, Section 16.6 step 5
* Proxy Behavior - Request Forwarding - Add Additional Header Fields
*/
/* NOT IMPLEMENTED (optional) */
/*
* RFC 3261, Section 16.6 step 6
* Proxy Behavior - Request Forwarding - Postprocess routing information
*
* If the copy contains a Route header field, the proxy MUST
* inspect the URI in its first value. If that URI does not
* contain an lr parameter, the proxy MUST modify the copy as
* follows:
*
* - The proxy MUST place the Request-URI into the Route header
* field as the last value.
*
* - The proxy MUST then place the first Route header field value
* into the Request-URI and remove that value from the Route
* header field.
*/
#if 0
route_postprocess(ticket);
#endif
/*
* RFC 3261, Section 16.6 step 7
* Proxy Behavior - Determine Next-Hop Address
*/
/*&&&& priority probably should be:
* 1) Route header
* 2) fixed outbound proxy
* 3) SIP URI
*/
/*
* fixed or domain outbound proxy defined ?
*/
if ((type == REQTYP_OUTGOING) &&
(sip_find_outbound_proxy(ticket, &sendto_addr, &port) == STS_SUCCESS)) {
DEBUGC(DBCLASS_PROXY, "proxy_request: have outbound proxy %s:%i",
utils_inet_ntoa(sendto_addr), port);
/*
* Route present?
* If so, fetch address from topmost Route: header and remove it.
*/
} else if ((type == REQTYP_OUTGOING) &&
(request->routes && !osip_list_eol(request->routes, 0))) {
sts=route_determine_nexthop(ticket, &sendto_addr, &port);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_request: route_determine_nexthop failed");
return STS_FAILURE;
}
DEBUGC(DBCLASS_PROXY, "proxy_request: have Route header to %s:%i",
utils_inet_ntoa(sendto_addr), port);
/*
* destination from SIP URI
*/
} else {
/* get the destination from the SIP URI */
sts = get_ip_by_host(url->host, &sendto_addr);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_request: cannot resolve URI [%s]",
url->host);
return STS_FAILURE;
}
if (url->port) {
port=atoi(url->port);
} else {
port=SIP_PORT;
}
DEBUGC(DBCLASS_PROXY, "proxy_request: have SIP URI to %s:%i",
url->host, port);
}
/*
* RFC 3261, Section 16.6 step 8
* Proxy Behavior - Add a Via header field value
*/
/* add my Via header line (outbound interface)*/
if (type == REQTYP_INCOMING) {
sts = sip_add_myvia(ticket, IF_INBOUND);
if (sts == STS_FAILURE) {
ERROR("adding my inbound via failed!");
}
} else {
sts = sip_add_myvia(ticket, IF_OUTBOUND);
if (sts == STS_FAILURE) {
ERROR("adding my outbound via failed!");
return STS_FAILURE;
}
}
/*
* RFC 3261, Section 16.6 step 9
* Proxy Behavior - Add a Content-Length header field if necessary
*/
/* not necessary, already in message and we do not support TCP */
/*
* RFC 3261, Section 16.6 step 10
* Proxy Behavior - Forward the new request
*/
sts = sip_message_to_str(request, &buffer, &buflen);
if (sts != 0) {
ERROR("proxy_request: sip_message_to_str failed");
return STS_FAILURE;
}
sipsock_send(sendto_addr, port, ticket->protocol,
buffer, buflen);
osip_free (buffer);
/*
* RFC 3261, Section 16.6 step 11
* Proxy Behavior - Set timer C
*/
/* NOT IMPLEMENTED - does this really apply for stateless proxies? */
return STS_SUCCESS;
}
/*
* PROXY_RESPONSE
*
* RETURNS
* STS_SUCCESS on success
* STS_FAILURE on error
* RFC3261
* Section 16.7: Proxy Behavior - Response Processing
* 1. Find the appropriate response context
* 2. Update timer C for provisional responses
* 3. Remove the topmost Via
* 4. Add the response to the response context
* 5. Check to see if this response should be forwarded immediately
* 6. When necessary, choose the best final response from the
* response context
* 7. Aggregate authorization header field values if necessary
* 8. Optionally rewrite Record-Route header field values
* 9. Forward the response
* 10. Generate any necessary CANCEL requests
*
*/
int proxy_response (sip_ticket_t *ticket) {
int i;
int sts;
int type;
struct in_addr sendto_addr;
osip_via_t *via;
int port;
char *buffer;
int buflen;
osip_message_t *response;
struct sockaddr_in *from;
DEBUGC(DBCLASS_PROXY,"proxy_response");
if (ticket==NULL) {
ERROR("proxy_response: called with NULL ticket");
return STS_FAILURE;
}
response=ticket->sipmsg;
from=&ticket->from;
/*
* RFC 3261, Section 16.7 step 3
* Proxy Behavior - Response Processing - Remove my Via header field value
*/
/* remove my Via header line */
sts = sip_del_myvia(ticket);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY,"not addressed to my VIA, ignoring response");
return STS_FAILURE;
}
/*
* figure out if this is an request coming from the outside
* world to one of our registered clients
*/
/* Ahhrghh...... a response seems to have NO contact information...
* so let's take FROM instead...
* the TO and FROM headers are EQUAL to the request - that means
* they are swapped in their meaning for a response...
*/
#if _OLD_DIRECTION_EVALUATION
type = 0;
for (i=0; i<URLMAP_SIZE; i++) {
if (urlmap[i].active == 0) continue;
/* incoming response ('from' == 'masq') || ('from' == 'reg') */
if ((compare_url(response->from->url, urlmap[i].reg_url)==STS_SUCCESS) ||
(compare_url(response->from->url, urlmap[i].masq_url)==STS_SUCCESS)) {
type=RESTYP_INCOMING;
DEBUGC(DBCLASS_PROXY,"incoming response for %s@%s from outbound",
response->from->url->username? response->from->url->username:"******",
response->from->url->host? response->from->url->host : "*NULL*");
break;
}
/* outgoing response ('to' == 'reg') || ('to' == 'masq' ) */
if ((compare_url(response->to->url, urlmap[i].masq_url)==STS_SUCCESS) ||
(compare_url(response->to->url, urlmap[i].reg_url)==STS_SUCCESS)){
type=RESTYP_OUTGOING;
DEBUGC(DBCLASS_PROXY,"outgoing response for %s@%s from inbound",
response->from->url->username ?
response->from->url->username : "******",
response->from->url->host ?
response->from->url->host : "*NULL*");
break;
}
}
#else
type = 0;
/*
* did I receive the telegram from a REGISTERED host?
* -> it must be an OUTGOING response
*/
for (i=0; i<URLMAP_SIZE; i++) {
struct in_addr tmp_addr;
if (urlmap[i].active == 0) continue;
if (get_ip_by_host(urlmap[i].true_url->host, &tmp_addr) == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_response: cannot resolve host [%s]",
urlmap[i].true_url);
} else {
DEBUGC(DBCLASS_PROXY, "proxy_response: reghost:%s ip:%s",
urlmap[i].true_url->host, utils_inet_ntoa(from->sin_addr));
if (memcmp(&tmp_addr, &from->sin_addr, sizeof(tmp_addr)) == 0) {
type=RESTYP_OUTGOING;
break;
}
}
}
/*
* is the telegram directed to an internal registered host?
* -> it must be an INCOMING response
*/
if (type == 0) {
for (i=0; i<URLMAP_SIZE; i++) {
if (urlmap[i].active == 0) continue;
/* incoming response ('from' == 'masq') || ('from' == 'reg') */
if ((compare_url(response->from->url, urlmap[i].reg_url)==STS_SUCCESS) ||
(compare_url(response->from->url, urlmap[i].masq_url)==STS_SUCCESS)) {
type=RESTYP_INCOMING;
break;
}
}
}
/* &&&& Open Issue &&&&
it has been seen with cross-provider calls that the FROM may be 'garbled'
(e.g [email protected] for calls made sipphone -> FWD)
How can we deal with this? Should I take into consideration the 'Via'
headers? This is the only clue I have, pointing to the *real* UA.
Maybe I should put in a 'siproxd' ftag value to recognize it as a header
inserted by myself
*/
if ((type == 0) && (!osip_list_eol(response->vias, 0))) {
osip_via_t *via;
struct in_addr addr_via, addr_myself;
int port_via, port_ua;
/* get the via address */
via = (osip_via_t *) osip_list_get (response->vias, 0);
DEBUGC(DBCLASS_PROXY, "proxy_response: check via [%s] for "
"registered UA",via->host);
sts=get_ip_by_host(via->host, &addr_via);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_DNS, "proxy_response: cannot resolve VIA [%s]",
via->host);
} else {
for (i=0; i<URLMAP_SIZE; i++) {
if (urlmap[i].active == 0) continue;
/* incoming response (1st via in list points to a registered UA) */
sts=get_ip_by_host(urlmap[i].true_url->host, &addr_myself);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_DNS, "proxy_response: cannot resolve "
"true_url [%s]", via->host);
continue;
}
port_via=0;
if (via->port) port_via=atoi(via->port);
if (port_via <= 0) port_via=SIP_PORT;
port_ua=0;
if (urlmap[i].true_url->port)
port_ua=atoi(urlmap[i].true_url->port);
if (port_ua <= 0) port_ua=SIP_PORT;
DEBUGC(DBCLASS_BABBLE, "proxy_response: checking for registered "
"host [%s:%i] <-> [%s:%i]",
urlmap[i].true_url->host, port_ua,
via->host, port_via);
if ((memcmp(&addr_myself, &addr_via, sizeof(addr_myself))==0) &&
(port_via == port_ua)) {
type=RESTYP_INCOMING;
break;
}
}
}
}
#endif
ticket->direction=type;
/*
* ok, we got a response that we are allowed to process.
*/
switch (type) {
/*
* from an external host to the internal masqueraded host
*/
case RESTYP_INCOMING:
DEBUGC(DBCLASS_PROXY,"incoming response for %s@%s from outbound",
response->from->url->username? response->from->url->username:"******",
response->from->url->host? response->from->url->host : "*NULL*");
/*
* Response for INVITE - deal with RTP data in body and
* start RTP proxy stream(s). In case
* of a negative answer, stop RTP stream
*/
if (MSG_IS_RESPONSE_FOR(response,"INVITE")) {
/* positive response, start RTP stream */
if ((MSG_IS_STATUS_1XX(response)) ||
(MSG_IS_STATUS_2XX(response))) {
if (configuration.rtp_proxy_enable == 1) {
sts = proxy_rewrite_invitation_body(response, DIR_INCOMING);
}
/* negative - stop a possibly started RTP stream */
} else if ((MSG_IS_STATUS_4XX(response)) ||
(MSG_IS_STATUS_5XX(response)) ||
(MSG_IS_STATUS_6XX(response))) {
rtp_stop_fwd(osip_message_get_call_id(response), DIR_INCOMING);
rtp_stop_fwd(osip_message_get_call_id(response), DIR_OUTGOING);
}
} /* if INVITE */
/*
* Response for REGISTER - special handling of Contact header
*/
if (MSG_IS_RESPONSE_FOR(response,"REGISTER")) {
/*
* REGISTER returns *my* Contact header information.
* Rewrite Contact header back to represent the true address.
* Other responses do return the Contact header of the sender.
*/
sip_rewrite_contact(ticket, DIR_INCOMING);
}
/*
* Response for SUBSCRIBE
*
* HACK for Grandstream SIP phones (with newer firmware like 1.0.4.40):
* They send a SUBSCRIBE request to the registration server. In
* case of beeing registering directly to siproxd, this request of
* course will eventually be forwarded back to the same UA.
* Grandstream then does reply with an '202' response (A 202
* response merely indicates that the subscription has been
* understood, and that authorization may or may not have been
* granted), which then of course is forwarded back to the phone.
* Ans it seems that the Grandstream can *not* *handle* this
* response, as it immediately sends another SUBSCRIBE request.
* And this games goes on and on and on...
*
* As a workaround we will transform any 202 response to a
* '404 unknown destination'
*
*/
{
osip_header_t *ua_hdr=NULL;
osip_message_get_user_agent(response, 0, &ua_hdr);
if (ua_hdr && ua_hdr->hvalue &&
(osip_strncasecmp(ua_hdr->hvalue,"grandstream", 11)==0) &&
(MSG_IS_RESPONSE_FOR(response,"SUBSCRIBE")) &&
(MSG_TEST_CODE(response, 202))) {
DEBUGC(DBCLASS_PROXY, "proxy_response: Grandstream hack 202->404");
response->status_code=404;
}
}
break;
/*
* from the internal masqueraded host to an external host
*/
case RESTYP_OUTGOING:
DEBUGC(DBCLASS_PROXY,"outgoing response for %s@%s from inbound",
response->from->url->username ?
response->from->url->username : "******",
response->from->url->host ?
response->from->url->host : "*NULL*");
/* rewrite Contact header to represent the masqued address */
sip_rewrite_contact(ticket, DIR_OUTGOING);
/*
* If an 2xx OK or 1xx response, answer to an INVITE request,
* rewrite body
*
* In case of a negative answer, stop RTP stream
*/
if (MSG_IS_RESPONSE_FOR(response,"INVITE")) {
/* positive response, start RTP stream */
if ((MSG_IS_STATUS_1XX(response)) ||
(MSG_IS_STATUS_2XX(response))) {
/* This is an outgoing response, therefore an outgoing stream */
sts = proxy_rewrite_invitation_body(response, DIR_OUTGOING);
/* megative - stop a possibly started RTP stream */
} else if ((MSG_IS_STATUS_4XX(response)) ||
(MSG_IS_STATUS_5XX(response)) ||
(MSG_IS_STATUS_6XX(response))) {
rtp_stop_fwd(osip_message_get_call_id(response), DIR_INCOMING);
rtp_stop_fwd(osip_message_get_call_id(response), DIR_OUTGOING);
}
} /* if INVITE */
break;
default:
DEBUGC(DBCLASS_PROXY, "response from/to unregistered UA (%s@%s)",
response->from->url->username? response->from->url->username:"******",
response->from->url->host? response->from->url->host : "*NULL*");
return STS_FAILURE;
}
/*
* for ALL incoming response include my Record-Route header.
* The local UA will probably send its answer to the topmost
* Route Header (8.1.2 of RFC3261)
*/
if (type == RESTYP_INCOMING) {
DEBUGC(DBCLASS_PROXY,"Adding my Record-Route");
route_add_recordroute(ticket);
} else {
/*
* outgoing packets must not have my record route header, as
* this likely will contain a private IP address (my inbound).
*/
DEBUGC(DBCLASS_PROXY,"Purging Record-Routes (outgoing packet)");
route_purge_recordroute(ticket);
}
/*
* Determine Next-Hop Address
*/
/*&&&& priority probably should be:
* 1) Route header
* 2) fixed outbound proxy
* 3) SIP URI
*/
/*
* check if we need to send to an outbound proxy
*/
if ((type == RESTYP_OUTGOING) &&
(sip_find_outbound_proxy(ticket, &sendto_addr, &port) == STS_SUCCESS)) {
DEBUGC(DBCLASS_PROXY, "proxy_response: have outbound proxy %s:%i",
utils_inet_ntoa(sendto_addr), port);
/*
* Route present?
* If so, fetch address from topmost Route: header and remove it.
*/
} else if ((type == RESTYP_OUTGOING) &&
(response->routes && !osip_list_eol(response->routes, 0))) {
sts=route_determine_nexthop(ticket, &sendto_addr, &port);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_response: route_determine_nexthop failed");
return STS_FAILURE;
}
DEBUGC(DBCLASS_PROXY, "proxy_response: have Route header to %s:%i",
utils_inet_ntoa(sendto_addr), port);
} else {
/* get target address and port from VIA header */
via = (osip_via_t *) osip_list_get (response->vias, 0);
if (via == NULL) {
ERROR("proxy_response: list_get via failed");
return STS_FAILURE;
}
sts = get_ip_by_host(via->host, &sendto_addr);
if (sts == STS_FAILURE) {
DEBUGC(DBCLASS_PROXY, "proxy_response: cannot resolve VIA [%s]",
via->host);
return STS_FAILURE;
}
if (via->port) {
port=atoi(via->port);
} else {
port=SIP_PORT;
}
}
sts = sip_message_to_str(response, &buffer, &buflen);
if (sts != 0) {
ERROR("proxy_response: sip_message_to_str failed");
return STS_FAILURE;
}
sipsock_send(sendto_addr, port, ticket->protocol,
buffer, buflen);
osip_free (buffer);
return STS_SUCCESS;
}