[Serusers] SER SDP Port Problem??

[Greger V. Teigre]

Aisling,
The port is in the m= line. You use nat_uac_test("3"). Any particular reason 
for not using all tests?
Please note that sdp rewriting does not work if the UA is behind a symmetric 
NAT and you are calling in. You must then via an RTP proxy like mediaproxy 
or rtpproxy.
g-)

Aisling O'Driscoll wrote:
> Hi,
>
> I understand the basic problem behind one way audio is that the
> client behind nat has a private address in the sdp information,
> therefore the voice cannot be delivered to this private address. It
> is necessary to rewrite this sdp info with the nat public address.
> However I have done this in my ser.cfg and I still have one way
> voice.
>
> I have included some of relevant ethereal messages on SER and my
> ser.cfg below. The messages show that the rtp information has been
> changed. Does anyone think the problem is because there is no port
> information in the "c" and "o" fields in the sdp?? If so how can I
> make sure the port is included?
>
> Many Thanks,
> Aisling.
>
> Ethereal messages:
>
> call between private client with public nat address 63.218.54.71 and
> a public client with address 157.190.183.80. The SER address is
> 157.190.183.70.
>
> REGISTER sip:157.190.183.70 SIP/2.0
> VIA: SIP/2.0/UDP 63.218.54.71:11987;rport;branch=z9h.....
> FROM: whoever <sip:2008 at 157.190.183.70>;tag=455....
> TO: whoever <sip:2008 at 157.190.183.70>
> CONTACT: "whoever" <sip:2008 at 63.218.54.71:11987>
> Call-Id: ....
> CSeq: 22227 REGISTER
> Expires; 1800
> User Agent: X-Lite release 1103m
> Content-Length: 0
>
> SIP/2.0 200 OK
> VIA: SIP/2.0/UDP 63.218.54.71:11987;rport;branch=z9h.....
> FROM: whoever <sip:2008 at 157.190.183.70>;tag=455....
> TO: whoever <sip:2008 at 157.190.183.70>
> CONTACT: "whoever" <sip:2008 at 63.218.54.71:11987>;q=0.00 expires=1800
> Call-Id: ....
> CSeq: 22227 REGISTER
> Expires; 1800
> User Agent: X-Lite release 1103m
> Content-Length: 0
>
> The public client (157.190.183.80 also registers)
>
> Then the private client invites the public client to a voice
> conversation:
>
> INVITE sip:2001 at 157.190.183.70 SIP/2.0
> VIA: SIP/2.0/UDP 63.218.54.71:11987;rport;branch=z9h.....
> FROM: whoever <sip:2008 at 157.190.183.70>;tag=455....
> TO: whoever <sip:2001 at 157.190.183.70>
> CONTACT: "whoever" <sip:2008 at 63.218.54.71:11987>
> Call-Id: ....
> CSeq: 19929 INVITE
> Expires; 1800
> User Agent: X-Lite release 1103m
> Content-Type=application/sdp
> Content-Length: 290
>
>   Session description Protocol
>   Owner/Creator of the Session (o): 2008 245812 272828 IN IP4
> 63.218.54.71
>   Connection information (c): IN IP4 63.218.54.71
>
> A 100 Trying is sent back from SER to the private client (i.e. caller)
>
> The INVITE is forwarded from SER to public client (callee) as show
> below:
>
> INVITE sip:2001 at 157.190.183.70 SIP/2.0
> VIA: SIP/2.0/UDP 157.190.183.70;branch=....
> VIA: SIP/2.0/UDP 63.218.54.71:11987;branch=z9h.....
> FROM: whoever <sip:2008 at 157.190.183.70>;tag=455....
> TO: whoever <sip:2001 at 157.190.183.70>
> CONTACT: "whoever" <sip:2008 at 63.218.54.71:11987>
> Call-Id: ....
> CSeq: 19929 INVITE
> Expires; 1800
> User Agent: X-Lite release 1103m
> Content-Type=application/sdp
> Content-Length: 290
>
>   Session description Protocol
>   Owner/Creator of the Session (o): 2008 245812 272828 IN IP4
> 63.218.54.71
>   Connection information (c): IN IP4 63.218.54.71
>
> 157.190.183.80 157.190.183.70 SIP 100 Trying
> 157.190.183.80 157.190.183.70 SIP 180 Ringing
> 157.190.183.70 63.218.54.71 SIP 180 Ringing
>
> 157.190.183.80 157.190.183.70 SIP/SDP Status: 200OK
>
> SIP/2.0 200 OK
> Via: SIP/2.0/UDP 157.190.183.70;branch=....
> Via: SIP/2.0/UDP 63.218.54.71:11987;rport=11987;branch=.....
> From: whoever<sip:2008 at 157.190.183.70>;tag=...
> To: <sip:2001 at 157.190.183.70>;tag=....
> CSeq: 19929 INVITE
> User Agent: Grandtsream BT100 1.0.5.18
> Contact: <sip:2001 at 157.190.183.80>
>
>    Session description protocol
>    (c) IN IP4 157.190.183.80
>
>
> #
> # $Id: ser.cfg,v 1.21.4.1 2003/11/10 15:35:15 andrei Exp $
> #
> # simple quick-start config script
> #
>
> # ----------- global configuration parameters ------------------------
>
> #debug=3         # debug level (cmd line: -dddddddddd)
> #fork=yes
> #log_stderror=no # (cmd line: -E)
>
> /* Uncomment these lines to enter debugging mode
> debug=7
> fork=no
> log_stderror=yes
> */
>
> check_via=no # (cmd. line: -v)
> dns=no           # (cmd. line: -r)
> rev_dns=no      # (cmd. line: -R)
> #port=5060
> #children=4
> fifo="/tmp/ser_fifo"
>
> alias="157.190.183.70:5060"
>
> # ------------------ module loading ----------------------------------
>
> # Uncomment this if you want to use SQL database
> loadmodule "/usr/lib/ser/modules/mysql.so"
>
> loadmodule "/usr/lib/ser/modules/sl.so"
> loadmodule "/usr/lib/ser/modules/tm.so"
> loadmodule "/usr/lib/ser/modules/rr.so"
> loadmodule "/usr/lib/ser/modules/maxfwd.so"
> loadmodule "/usr/lib/ser/modules/usrloc.so"
> loadmodule "/usr/lib/ser/modules/registrar.so"
> loadmodule "/usr/lib/ser/modules/textops.so"
> loadmodule "/usr/lib/ser/modules/nathelper.so"
>
> # Uncomment this if you want digest authentication
> # mysql.so must be loaded !
> loadmodule "/usr/lib/ser/modules/auth.so"
> loadmodule "/usr/lib/ser/modules/auth_db.so"
>
> # ----------------- setting module-specific parameters ---------------
>
> # -- usrloc params --
>
> #modparam("usrloc", "db_mode",   0)
>
> # Uncomment this if you want to use SQL database
> # for persistent storage and comment the previous line
> modparam("usrloc", "db_mode", 2)
>
> # -- auth params --
> # Uncomment if you are using auth module
> #
> #modparam("auth_db", "calculate_ha1", yes)
> #
> # If you set "calculate_ha1" parameter to yes (which true in this
> config),
> # uncomment also the following parameter)
> #
> #modparam("auth_db", "password_column", "password")
>
> # -- rr params --
> # add value to ;lr param to make some broken UAs happy
> #NB Had to up this value from 1 to 11 because reinvites were
> bombarding called phone
> modparam("rr", "enable_full_lr", 11)
>
> #!! Nathelper
> modparam("registrar", "nat_flag", 6)
> modparam("nathelper", "natping_interval", 30) #Ping interval 30 s
> modparam("nathelper", "ping_nated_only", 1)   #Ping only clients
> behind NAT
>
> modparam("tm", "fr_inv_timer", 80)
>
> # -------------------------  request routing logic -------------------
>
> # main routing logic
>
> route{
>
> # initial sanity checks -- messages with
> # max_forwards==0, or excessively long requests
> if (!mf_process_maxfwd_header("10")) {
> sl_send_reply("483","Too Many Hops");
> break;
> };
> if ( msg:len > max_len ) {
> sl_send_reply("513", "Message too big");
> break;
> };
>
> #########################added for cit client behind nat
> 09/02/05#######################
> if (nat_uac_test("3")){
> if (method == "REGISTER" || ! search("^Record-Route:")){
> log("Log: Someone trying to register from private IP,rewriting\n");
> fix_nated_contact(); #Rewrite contact with source IP
> if (method == "INVITE"){
> fix_nated_sdp("1"); #Add direction=active to SDP
> };
> force_rport(); # Add rport parameter to topmost Via
> setflag(6); # Mark as Nated
> };
> };
> #####################################################################
> ###################
>
> # we record-route all messages -- to make sure that
> # subsequent messages will go through our proxy; that's
> # particularly good if upstream and downstream entities
> # use different transport protocol
>
> if (method =="REGISTER") record_route();
>
> # loose-route processing
> if (loose_route()) {
> #commented 11/02/05
> #t_relay();
> route(1);
> break;
> };
>
> # if the request is for other domain use UsrLoc
> # (in case, it does not work, use the following command
> # with proper names and addresses in it)
> if (uri==myself) {
>
> log(1,"into loop");
> if (method=="REGISTER") {
>
> # Uncomment this if you want to use digest authentication
> # if (!www_authorize("157.190.183.70", "subscriber")) {
> # www_challenge("157.190.183.70", "0");
> # break;
> # };
>
> save("location");
> break;
> };
>
> lookup("aliases");
> if (!uri==myself) {
> append_hf("P-hint: outbound alias\r\n");
> route(1);
> break;
> };
>
> if (method=="INVITE"){
> log(1,"in invite loop");
> #break; #no 100 trying
> t_on_failure("1");
> };
>
> # native SIP destinations are handled using our USRLOC DB
> if (!lookup("location")) {
> #sl_send_reply("404", "Not Found");
> route(2);
> break;
> };
> };
>
> # forward to current uri now; use stateful forwarding; that
> # works reliably even if we forward from TCP to UDP
> #commented 11/02/05#######################
> if (!t_relay()) {
> sl_reply_error();
> };
>
> }
>
> ######################################entered
> 11/02/05############################################################
> route[1]
> {
> #!!Nathelper
> if(uri=~"[@:](192\.168\.|10\.|172\.(1[6-9]|2[0-9]|3[0-1])\.)" &&
> !search("^Route:")){
> sl_send_reply("479", "We don't forward to private IP addresses");
> break;
> };
>
> t_on_reply("1");
>
> if(!t_relay()){
> sl_reply_error();
> };
> }
> ######################################entered
> 11/02/05############################################################
> #!! Nathelper
> onreply_route[1]{
> if(isflagset(6) && status =~ "(183)|2[0-9][0-9]"){
> fix_nated_contact();
> force_rtp_proxy();
> } else if (nat_uac_test("1")){
> fix_nated_contact();
> };
> }
> ######################################################################
> ###########################################
>
> # ------------- handling of unavailable user ------------------
> route[2] {
>
>        # non-Voip -- just send "off-line"
>        if (!(method == "INVITE" || method == "ACK" || method ==
> "CANCEL")) {
>                sl_send_reply("404", "Not Found");
>                break;
>        };
>
>        # forward to voicemail now
>        rewritehostport("157.190.183.70:5062");
>        t_relay_to_udp("157.190.183.70", "5062");
> }
>
> # if forwarding downstream did not succeed, try voicemail running
> # at 157.190.183.70:5062
>
> failure_route[1] {
>        revert_uri();
>        rewritehostport("157.190.183.70:5062");
>        append_branch();
>        t_relay_to_udp("157.190.183.70", "5062");
> }
>
>
>
>
>
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