Hi, I have encounter a new problem with sdp negociation. Like I said before, my code is based on simpleua.c, and I'm trying to have the following call flow : UAC -------Invite (a)--------->B2BUA---------Invite (b)--------->UAS UAC <------------------------200 ok (c)-----------------------------------UAS UAC ----------------------------ACK----------------------------------------->UAS UAC -------------------------------BYE-------------------------------------->UAS UAC <------------------------200 ok ---------------------------------------UAS UAC ----------------------------ACK---------------------------------------->UAS where : INVITE (a) contain a sdp with the following media in SDP (only this one) m=application 0 ESP_TRANSPORT/UDP a=crypto:1 ESP_AES_CBC_128_HMAC_MD5_96 inline:|any|192.168.209.20: |24500::|:: This part is ok, I can send this sdp INVITE (b) is updated by my B2BUA : m=application 0 ESP_TRANSPORT/UDP a=crypto:1 ESP_AES_CBC_128_HMAC_MD5_96 inline:4avswQmkSryflkF851qRPg==|any|192.168.209.20:|24500:sec:3600|:sec:3600 (in one line) and my UAS respond to this message with the following SDP in 200 ok : m=application 0 ESP_TRANSPORT/UDP a=crypto:1 ESP_AES_CBC_128_HMAC_MD5_96 inline:4avswQmkSryflkF851qRPg==|any|192.168.209.20:192.168.209.21|24500:sec:3600|24500:sec:3600 (in one line) So, now, I have what I want in my SDP in both the request and the answer. But, when I'm checking pjsip logs, I encounter the following message : simpleua.c Call state changed to CONNECTING inv0x811277c Got SDP answer in Response msg 200/INVITE/cseq=4056 (rdata0x80ebdc4) inv0x811277c SDP negotiation done, status=220046 simpleua.c SDP negotiation has failed: SDP media transport type mismatch in offer/answer (PJMEDIA_SDPNEG_EINVANSTP) [code=220046] The last line is logged during on_media_update (it's the first operation, when we check the status). And, when I'm watching with a debugger the value of neg in my invite session, I can observe the following values : - state : PJMEDIA_SDP_NEG_STATE_DONE - has_remote_answer : 0 - answer_was_remote : 1 (I don't understand why it's not 1 and 1 for these ones) - initial_sdp : 0x8112f4c (valid address, which contain, logically, the sdp of INVITE (a)) - active_local_sdp : 0x0 - active_remote_sdp : 0x0 - neg_local_sdp : 0x0 - neg_remote_sdp : 0x0 So, my sdp negociation failed, but I can't understand why (same media, same attribute. Only inline value has changes), and where can I do a workaround to evade this problem ? I try to add a callback on_rx_response, but this one doesn't fire before on_media_update. Can someone help me on this problem ? Regards, On Tue, Nov 18, 2008 at 11:09 AM, Pierrick Grasland < pierrick.grasland at gmail.com> wrote: > Hi, > > Thanks for your help, but I prefered to only modify SDP on rx_request > callback. > > So, because I'm only working with one media, and I'm sure of > negociation value, I recreate a new sdp negociator in simpleua.c. I > use pjmedia_sdp_neg_create_w_remote_offer and replace remote sdp with > my new local sdp value. This negociator replace g_inv->negociator. > > After that, I used simpleua mechanism to negociate a valid answer > between local_sdp and local_sdp (param of pjsip_inv_answer, for 200 > ok). > > Regards, > > On Mon, Nov 17, 2008 at 6:04 PM, Nanang Izzuddin <nanang at pjsip.org> wrote: > > Hi, > > > > I think you should modify the SDP after SDP negotiated in the > > pjsip_inv_answer(), since the SDP negotiator may rearrange the SDP > > answer regarding RFC 3264 Section 6: > > For each "m=" line in the offer, there MUST be a corresponding "m=" > > line in the answer. The answer MUST contain exactly the same number > > of "m=" lines as the offer. > > For example, you can modify the SDP in > > pjsip_inv_callback.on_media_update (call_on_media_update() in > > simpleua.c). Please notice about corresponding 'm=' line, so instead > > of resetting media_count to zero and reassign it, I guess it is better > > to iterate the media in the local_sdp to find the m=application line > > and modify it there, except you are sure there will be only one media. > > > > Regards, > > nanang > > > > > > On Mon, Nov 17, 2008 at 10:02 PM, pierrick grasland > > <pierrick.grasland at nexcom.fr> wrote: > >> Hello all, > >> > >> I'm currently working with pjsip, in order to exchange information with > >> m=application SDP header. > >> > >> Actually, what I need is to do the following : > >> > >> receive SDP offer with : > >> > >> m=application \r\n a=crypto:values (easily done with pjsua.) > >> > >> Generate a new sdp media, with updated value (media2): > >> > >> something like that : m=application \r\n a=crypto:updated_values (done) > >> > >> I add this new media in my current sdp, and try to respond to my INVITE > (I'm > >> starting from simpleua.c,). > >> > >> status = pjmedia_endpt_create_sdp( g_med_endpt, rdata->tp_info.pool, > 1, > >> &g_med_tpinfo.sock_info, > >> &local_sdp); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> /* removing all sdp value */ > >> local_sdp->media_count = 0; > >> /* updating local_sdp */ > >> local_sdp->media_count ++; /* increment media count */ > >> local_sdp->media[local_sdp->media_count - 1] = media2; /* store > media in > >> sdp's array of media */ > >> > >> > >> I'm only interested in exchanging media2, so all other medias has been > >> deleted. > >> Then, I'm using simple_ua to send my 200 OK : > >> > >> /* > >> * Create invite session, and pass the UAS dialog > >> */ > >> status = pjsip_inv_create_uas( dlg, rdata, local_sdp, 0, &g_inv); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> > >> /* > >> * Now create 180 response. > >> */ > >> status = pjsip_inv_initial_answer(g_inv, rdata, > >> 180, > >> NULL, NULL, &tdata); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> > >> /* Send the 180 response. */ > >> status = pjsip_inv_send_msg(g_inv, tdata); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> > >> /* > >> * Now create 200 response. > >> */ > >> status = pjsip_inv_answer( g_inv, > >> 200, NULL, /* st_code and st_text */ > >> NULL, /* SDP specified now, in order to solve > >> local/remote confusion */ > >> &tdata); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> > >> /* > >> * Send the 200 response. > >> */ > >> status = pjsip_inv_send_msg(g_inv, tdata); > >> PJ_ASSERT_RETURN(status == PJ_SUCCESS, PJ_TRUE); > >> > >> > >> return PJ_TRUE; > >> > >> But, now, I have a problem : > >> > >> the body of my 200 OK contain the following media : > >> > >> m=application \r\n a=crypto:values > >> > >> instead of m=application \r\n a=crypto:updated_values > >> > >> After several search in PJLIB documentation, I found pj_bool_t > >> prefer_remote_codec_order; > >> Initialized at true, it first seem to be the origin of my problem. But > after > >> some trials, it doesn't have any effect on my response. > >> > >> I don't want to modify PJLIB, for future upgrade. Can someone help me, > and > >> show me some documentation on how to create our sdp ? > >> > >> Thanks for your help. > >> -- > >> Pierrick Grasland > >> > >> > >> _______________________________________________ > >> Visit our blog: http://blog.pjsip.org > >> > >> pjsip mailing list > >> pjsip at lists.pjsip.org > >> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > >> > >> > > > > _______________________________________________ > > Visit our blog: http://blog.pjsip.org > > > > pjsip mailing list > > pjsip at lists.pjsip.org > > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > > > > > -- > Pierrick Grasland > -- Pierrick Grasland -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20081119/52e85014/attachment.html>
