[Devel] Extended nathelper
Walter Schober
walter.schober at neotel.at
Fri Mar 3 17:28:12 CET 2006
Sure! If the outcome is the same, that would do it also!
And it's more controllable in the script.
P.S.: I was happy that it worked at all, that I didn't look for a better
solution :-)
-----Original Message-----
From: Bogdan-Andrei Iancu [mailto:bogdan at voice-system.ro]
Sent: Friday, March 03, 2006 5:08 PM
To: Walter Schober
Cc: devel at openser.org
Subject: Re: [Devel] Extended nathelper
Hi,
in this case shouldn't be simpler just to add an parameter to
add_rvc_param() to tell if the received should be added as URI param or
header param?
will this cover your scenario?
regards,
Bogdan
Walter Schober wrote:
>Hi!
>
>The difference is, that a received parameter is added behind the Contact
URI
>not as URI parameter, but a contact parameter:
>Contact:
><sip:0123456 at 1.2.3.4:5060;x-orig=11.11.11.11:5064;x-orig-nat=192.168.40.99:
5
>064>;received="sip:11.11.11.11:5064"
>
>And that one is not stored in the ContactDB of the next proxy. That one
>stores the SIP URI in the contact only.
>Thus the received parameter is not included in the sucessive Invite.
>
>BTW: I cannot change the behaviour of that proxy.
>
>Br
>Walter
>
>-----Original Message-----
>From: Bogdan-Andrei Iancu [mailto:bogdan at voice-system.ro]
>Sent: Friday, March 03, 2006 12:51 PM
>To: Walter Schober
>Cc: devel at openser.org
>Subject: Re: [Devel] Extended nathelper
>
>Hi Walter,
>
>thanks for email.
>
>First I want to see if there is some difference between the new function
>you add and the already existing function add_rcv_param().
> http://openser.org/docs/modules/1.0.x/nathelper.html#AEN331
>
>Regards,
>Bogdan
>
>
>Walter Schober wrote:
>
>
>
>>Hi!
>>
>>Maybe someone find's that useful. It's nearly the same than mangler,
>>but the difference is, that it stores the old values, too.
>>
>>Short description: nathelper stores original contact + addr:port from
>>where the request was received and puts itself in the list to register
>>a client on the next proxy. Keepalive has to be done by other methods.
>>
>>See details in attached readme.
>>
>>/Walter
>>
>>
>>------------------------------------------------------------------------
>>
>>Nathelper Patch for registering on remote proxies
>>-------------------------------------------------
>>
>>V 0.2
>>20060212
>>WSC walter.schober at neotel.at
>>
>>-------------------------------------------------
>>
>>Description: Openser is placed in front of another proxy not supporting
RFC
>>
>>
>3327 (Patch Header Support).
>
>
>>Using module nathelper the OpenSER detects nated clients and modifies the
>>
>>
>Contact field of the register.
>
>
>>The Contact header is expanded by a new "route", which is substituted
>>
>>
>instead of the IP:Port the
>
>
>>register is received from.
>>The operation is done after fixing the Contact in
>> fix_nated_contact();
>>Original fix_nated_contact() just replaces the host:port with host:port
>>
>>
>from where the request was
>
>
>>received from.
>>If the module parameter "contact_expander" is set, this value is inserted
>>
>>
>behind the user@ replacing the
>
>
>>fixed original host port.
>>e.g. original Contact is
>> Contact:
>>
>>
><sip:user at 192.168.1.1:5555;some-uri-param>;additional-params
>
>
>>the fix_nated_contact() replaces that with the IP from where the request
>>
>>
>was received from:
>
>
>> Contact: <sip:user at some_ip:port;some-uri-param>;additional-params
>>
>>If contact_expander is set, this string is inserted as
>> Contact:
>>
>>
><sip:user at value-of-contact-expander;x-orig=some_ip:port;x-orig-nat=original
-
>contact;some-uri-param>;additional-params
>
>
>>e.g. contact_exander = 1.2.3.4:5066, resulting in
>> Contact:
>>
>>
><sip:user at 1.2.3.4:5066;x-orig=33.44.55.66:5066;x-orig-nat=192.168.1.1:5062;
s
>ome-uri-param>;additional-params
>
>
>>
>>A Invite to such a contact results in
>> INVITE
>>
>>
>sip:user at 1.2.3.4:5066;x-orig=33.44.55.66:5066;x-orig-nat=192.168.1.1:5062;s
o
>me-uri-param
>
>
>>which could be replaced by e.g. textops and avp_ops
>> avp_write("$ruri","$x-orig");
>> if (subst_uri('/^sip:(.+)@.*;x-orig-nat=(.*)$/sip:\1@\2/i')) {
>>
>>
>>
>avp_subst("$x-orig","/^(.*)@.*;x-orig=(.*);x-orig-nat=.*$/\1@\2/");
>
>
>> avp_pushto("$duri","$x-orig");
>> route(1);
>>
>>forwarding to the original contact address, but to NATed contact address.
>>
>>
>>New Module Param:
>>--------------------------------------------------
>>modparam("nathelper", "contact_expander", "1.2.3.4:5066")
>>
>>
>>New Function Call:
>>--------------------------------------------------
>>None.
>>
>>
>>Example:
>>--------------------------------------------------
>># add myself as an alias
>>alias=1.2.3.4:5066
>>
>># set contact_expander to myself
>>modparam("nathelper", "contact_expander", "1.2.3.4:5066")
>>
>># avpops
>>modparam("avpops", "avp_aliases", "x-orig=i:32")
>>
>># is request is directed to me
>>if (uri==myself) {
>> # check, if we have to restore old destination
>> avp_write("$ruri","$x-orig");
>> if (subst_uri('/^sip:(.+)@.*;x-orig-nat=(.*)$/sip:\1@\2/i')) {
>>
>>
>>
>avp_subst("$x-orig","/^(.*)@.*;x-orig=(.*);x-orig-nat=.*$/\1@\2/");
>
>
>> avp_pushto("$duri","$x-orig");
>> # forwared to destination
>> route(1);
>> return;
>> }
>>}
>>
>># ... do something ...
>>
>># fix the Register as usual
>>if (method=="REGISTER" || method=="INVITE" || method=="REFER") {
>> if (nat_uac_test("18")) {
>> fix_nated_contact();
>> force_rport();
>> append_hf("P-hint: nathelper applied\r\n");
>> } else {
>> append_hf("P-hint: nathelper not applied\r\n");
>> };
>>};
>>
>># ... continue ... do something with the request
>>
>>
>>Installation
>>----------------------------------------------------
>>Patch the nathelper.c located in modules/nathelper executing
>> cp nathelper.c nathelper.c.orig
>> patch nathelper.c <nathelper.patch
>>
>>Rebuild module nathelper
>> make modules=modules/nathelper modules
>> make install
>>
>>The patch is based on OpenSER 1.0.0.
>>
>>Changes are in function fix_nated_contact_f() only + parameter
definitions.
>>
>>Restart OpenSER.
>>
>>
>>-----------------------------------------------------
>>
>>
>>New function fix_nated_contact_f():
>>
>>static int
>>fix_nated_contact_f(struct sip_msg* msg, char* str1, char* str2)
>>{
>> int offset, len, len1;
>> char *cp, *buf, temp[2];
>> contact_t *c;
>> struct lump *anchor;
>> struct sip_uri uri;
>> str hostport;
>>
>> if (get_contact_uri(msg, &uri, &c) == -1)
>> return -1;
>> if ((c->uri.s < msg->buf) || (c->uri.s > (msg->buf + msg->len))) {
>> LOG(L_ERR, "ERROR: you can't call fix_nated_contact twice,
>>
>>
>"
>
>
>> "check your config!\n");
>> return -1;
>> }
>>
>> offset = c->uri.s - msg->buf;
>> anchor = del_lump(msg, offset, c->uri.len, HDR_CONTACT_T);
>> if (anchor == 0)
>> return -1;
>>
>> hostport = uri.host;
>> if (uri.port.len > 0)
>> hostport.len = uri.port.s + uri.port.len - uri.host.s;
>>
>> cp = ip_addr2a(&msg->rcv.src_ip);
>> len = c->uri.len + strlen(cp) + 6 /* :port */ - hostport.len + 1;
>>
>> if (contact_expander.len) {
>> LOG(L_DBG, "Expanding Contact: %s\n", contact_expander.s);
>> len += contact_expander.len + hostport.len + 20;
>> }
>> buf = pkg_malloc(len);
>>
>> if (buf == NULL) {
>> LOG(L_ERR, "ERROR: fix_nated_contact: out of memory\n");
>> return -1;
>> }
>>
>> temp[0] = hostport.s[0];
>> temp[1] = c->uri.s[c->uri.len];
>> c->uri.s[c->uri.len] = hostport.s[0] = '\0';
>>
>> if (contact_expander.len) {
>> // sip:user:password at host:port ->
>> //
>>
>>
>sip:user:password at HOST:PORT;x-orig=host:port;x-orig-nat=priv-host:priv-port
>
>
>> len1 = snprintf(buf, len,
>>
>>
>"%s%s;x-orig=%s:%d;x-orig-nat=%c%s", c->uri.s,
>
>
>> contact_expander.s,
>> cp, msg->rcv.src_port,
>> temp[0],
>> hostport.s + 1);
>> } else {
>> len1 = snprintf(buf, len, "%s%s:%d%s", c->uri.s, cp,
>>
>>
>msg->rcv.src_port,
>
>
>> hostport.s + hostport.len);
>> }
>>
>> if (len1 < len)
>> len = len1;
>> hostport.s[0] = temp[0];
>> c->uri.s[c->uri.len] = temp[1];
>> if (insert_new_lump_after(anchor, buf, len, HDR_CONTACT_T) == 0) {
>> pkg_free(buf);
>> return -1;
>> }
>> c->uri.s = buf;
>> c->uri.len = len;
>>
>> return 1;
>>}
>>
>>
>>
>>------------------------------------------------------------------------
>>
>>_______________________________________________
>>Devel mailing list
>>Devel at openser.org
>>http://openser.org/cgi-bin/mailman/listinfo/devel
>>
>>
>>
>>
>
>
>
>
>
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