示例#1
0
/* Match format in the SDP media offer and answer. */
PJ_DEF(pj_status_t) pjmedia_sdp_neg_fmt_match(pj_pool_t *pool,
					      pjmedia_sdp_media *offer,
					      unsigned o_fmt_idx,
					      pjmedia_sdp_media *answer,
					      unsigned a_fmt_idx,
					      unsigned option)
{
    const pjmedia_sdp_attr *attr;
    pjmedia_sdp_rtpmap o_rtpmap, a_rtpmap;
    unsigned o_pt;
    unsigned a_pt;

    o_pt = pj_strtoul(&offer->desc.fmt[o_fmt_idx]);
    a_pt = pj_strtoul(&answer->desc.fmt[a_fmt_idx]);

    if (o_pt < 96 || a_pt < 96) {
	if (o_pt == a_pt)
	    return PJ_SUCCESS;
	else
	    return PJMEDIA_SDP_EFORMATNOTEQUAL;
    }

    /* Get the format rtpmap from the offer. */
    attr = pjmedia_sdp_media_find_attr2(offer, "rtpmap", 
					&offer->desc.fmt[o_fmt_idx]);
    if (!attr) {
	pj_assert(!"Bug! Offer haven't been validated");
	return PJ_EBUG;
    }
    pjmedia_sdp_attr_get_rtpmap(attr, &o_rtpmap);

    /* Get the format rtpmap from the answer. */
    attr = pjmedia_sdp_media_find_attr2(answer, "rtpmap", 
					&answer->desc.fmt[a_fmt_idx]);
    if (!attr) {
	pj_assert(!"Bug! Answer haven't been validated");
	return PJ_EBUG;
    }
    pjmedia_sdp_attr_get_rtpmap(attr, &a_rtpmap);

    if (pj_stricmp(&o_rtpmap.enc_name, &a_rtpmap.enc_name) != 0 ||
	(o_rtpmap.clock_rate != a_rtpmap.clock_rate) ||
	(!(pj_stricmp(&o_rtpmap.param, &a_rtpmap.param) == 0 ||
	   (a_rtpmap.param.slen == 0 && o_rtpmap.param.slen == 1 &&
	    *o_rtpmap.param.ptr == '1') ||
	   (o_rtpmap.param.slen == 0 && a_rtpmap.param.slen == 1 &&
	    *a_rtpmap.param.ptr=='1'))))
    {
	return PJMEDIA_SDP_EFORMATNOTEQUAL;
    }

    return custom_fmt_match(pool, &o_rtpmap.enc_name,
			    offer, o_fmt_idx, answer, a_fmt_idx, option);
}
示例#2
0
/* Internal function to apply symmetric PT for the local answer. */
static void apply_answer_symmetric_pt(pj_pool_t *pool,
				      pjmedia_sdp_media *answer,
				      unsigned pt_cnt,
				      const pj_str_t pt_offer[],
				      const pj_str_t pt_answer[])
{
    pjmedia_sdp_attr *a_tmp[PJMEDIA_MAX_SDP_ATTR];
    unsigned i, a_tmp_cnt = 0;

    /* Rewrite the payload types in the answer if different to
     * the ones in the offer.
     */
    for (i = 0; i < pt_cnt; ++i) {
	pjmedia_sdp_attr *a;

	/* Skip if the PTs are the same already, e.g: static PT. */
	if (pj_strcmp(&pt_answer[i], &pt_offer[i]) == 0)
	    continue;

	/* Rewrite payload type in the answer to match to the offer */
	pj_strdup(pool, &answer->desc.fmt[i], &pt_offer[i]);

	/* Also update payload type in rtpmap */
	a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", &pt_answer[i]);
	if (a) {
	    rewrite_pt(pool, &a->value, &pt_answer[i], &pt_offer[i]);
	    /* Temporarily remove the attribute in case the new payload
	     * type is being used by another format in the media.
	     */
	    pjmedia_sdp_media_remove_attr(answer, a);
	    a_tmp[a_tmp_cnt++] = a;
	}

	/* Also update payload type in fmtp */
	a = pjmedia_sdp_media_find_attr2(answer, "fmtp", &pt_answer[i]);
	if (a) {
	    rewrite_pt(pool, &a->value, &pt_answer[i], &pt_offer[i]);
	    /* Temporarily remove the attribute in case the new payload
	     * type is being used by another format in the media.
	     */
	    pjmedia_sdp_media_remove_attr(answer, a);
	    a_tmp[a_tmp_cnt++] = a;
	}
    }

    /* Return back 'rtpmap' and 'fmtp' attributes */
    for (i = 0; i < a_tmp_cnt; ++i)
	pjmedia_sdp_media_add_attr(answer, a_tmp[i]);
}
示例#3
0
static void apply_packetization(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
			 const struct pjmedia_sdp_media *remote_stream)
{
	pjmedia_sdp_attr *attr;
	pj_str_t value;
	unsigned long framing;
	int codec;
	struct ast_codec_pref *pref = &ast_rtp_instance_get_codecs(session_media->rtp)->pref;

	/* Apply packetization if available and configured to do so */
	if (!session->endpoint->media.rtp.use_ptime || !(attr = pjmedia_sdp_media_find_attr2(remote_stream, "ptime", NULL))) {
		return;
	}

	value = attr->value;
	framing = pj_strtoul(pj_strltrim(&value));

	for (codec = 0; codec < AST_RTP_MAX_PT; codec++) {
		struct ast_rtp_payload_type format = ast_rtp_codecs_payload_lookup(ast_rtp_instance_get_codecs(
											   session_media->rtp), codec);

		if (!format.asterisk_format) {
			continue;
		}

		ast_codec_pref_setsize(pref, &format.format, framing);
	}

	ast_rtp_codecs_packetization_set(ast_rtp_instance_get_codecs(session_media->rtp),
					 session_media->rtp, pref);
}
示例#4
0
PJ_DEF(pj_status_t) pjmedia_codec_g7221_match_sdp(pj_pool_t *pool,
						  pjmedia_sdp_media *offer,
						  unsigned o_fmt_idx,
						  pjmedia_sdp_media *answer,
						  unsigned a_fmt_idx,
						  unsigned option)
{
    const pjmedia_sdp_attr *attr_ans;
    const pjmedia_sdp_attr *attr_ofr;
    pjmedia_sdp_fmtp fmtp;
    unsigned a_bitrate, o_bitrate;
    const pj_str_t bitrate = {"bitrate=", 8};
    pj_status_t status;

    PJ_UNUSED_ARG(pool);
    PJ_UNUSED_ARG(option);

    /* Parse offer */
    attr_ofr = pjmedia_sdp_media_find_attr2(offer, "fmtp", 
					    &offer->desc.fmt[o_fmt_idx]);
    if (!attr_ofr)
	return PJMEDIA_SDP_EINFMTP;

    status = pjmedia_sdp_attr_get_fmtp(attr_ofr, &fmtp);
    if (status != PJ_SUCCESS)
	return status;

    GET_FMTP_IVAL(o_bitrate, fmtp, bitrate, 0);

    /* Parse answer */
    attr_ans = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					    &answer->desc.fmt[a_fmt_idx]);
    if (!attr_ans)
	return PJMEDIA_SDP_EINFMTP;

    status = pjmedia_sdp_attr_get_fmtp(attr_ans, &fmtp);
    if (status != PJ_SUCCESS)
	return status;

    GET_FMTP_IVAL(a_bitrate, fmtp, bitrate, 0);

    /* Compare bitrate in answer and offer. */
    if (a_bitrate != o_bitrate)
	return PJMEDIA_SDP_EFORMATNOTEQUAL;

    return PJ_SUCCESS;
}
示例#5
0
static void get_codecs(struct ast_sip_session *session, const struct pjmedia_sdp_media *stream, struct ast_rtp_codecs *codecs)
{
	pjmedia_sdp_attr *attr;
	pjmedia_sdp_rtpmap *rtpmap;
	pjmedia_sdp_fmtp fmtp;
	struct ast_format *format;
	int i, num = 0;
	char name[256];
	char media[20];
	char fmt_param[256];

	ast_rtp_codecs_payloads_initialize(codecs);

	/* Iterate through provided formats */
	for (i = 0; i < stream->desc.fmt_count; ++i) {
		/* The payload is kept as a string for things like t38 but for video it is always numerical */
		ast_rtp_codecs_payloads_set_m_type(codecs, NULL, pj_strtoul(&stream->desc.fmt[i]));
		/* Look for the optional rtpmap attribute */
		if (!(attr = pjmedia_sdp_media_find_attr2(stream, "rtpmap", &stream->desc.fmt[i]))) {
			continue;
		}

		/* Interpret the attribute as an rtpmap */
		if ((pjmedia_sdp_attr_to_rtpmap(session->inv_session->pool_prov, attr, &rtpmap)) != PJ_SUCCESS) {
			continue;
		}

		ast_copy_pj_str(name, &rtpmap->enc_name, sizeof(name));
		ast_copy_pj_str(media, (pj_str_t*)&stream->desc.media, sizeof(media));
		ast_rtp_codecs_payloads_set_rtpmap_type_rate(codecs, NULL, pj_strtoul(&stream->desc.fmt[i]),
							     media, name, 0, rtpmap->clock_rate);
		/* Look for an optional associated fmtp attribute */
		if (!(attr = pjmedia_sdp_media_find_attr2(stream, "fmtp", &rtpmap->pt))) {
			continue;
		}

		if ((pjmedia_sdp_attr_get_fmtp(attr, &fmtp)) == PJ_SUCCESS) {
			sscanf(pj_strbuf(&fmtp.fmt), "%d", &num);
			if ((format = ast_rtp_codecs_get_payload_format(codecs, num))) {
				ast_copy_pj_str(fmt_param, &fmtp.fmt_param, sizeof(fmt_param));
				ast_format_sdp_parse(format, fmt_param);
			}
		}
	}
}
示例#6
0
/* Toggle AMR octet-align setting in the fmtp.
 */
static pj_status_t amr_toggle_octet_align(pj_pool_t *pool,
					  pjmedia_sdp_media *media,
					  unsigned fmt_idx)
{
    pjmedia_sdp_attr *attr;
    pjmedia_sdp_fmtp fmtp;
    const pj_str_t STR_OCTET_ALIGN = {"octet-align=", 12};
    
    enum { MAX_FMTP_STR_LEN = 160 };

    attr = pjmedia_sdp_media_find_attr2(media, "fmtp", 
					&media->desc.fmt[fmt_idx]);
    /* Check if the AMR media format has FMTP attribute */
    if (attr) {
	char *p;
	pj_status_t status;

	status = pjmedia_sdp_attr_get_fmtp(attr, &fmtp);
	if (status != PJ_SUCCESS)
	    return status;

	/* Check if the fmtp has octet-align field. */
	p = pj_stristr(&fmtp.fmt_param, &STR_OCTET_ALIGN);
	if (p) {
	    /* It has, just toggle the value */
	    unsigned octet_align;
	    pj_str_t s;

	    pj_strset(&s, p + STR_OCTET_ALIGN.slen, fmtp.fmt_param.slen -
		      (p - fmtp.fmt_param.ptr) - STR_OCTET_ALIGN.slen);
	    octet_align = pj_strtoul(&s);
	    *(p + STR_OCTET_ALIGN.slen) = (char)(octet_align? '0' : '1');
	} else {
	    /* It doesn't, append octet-align field */
	    char buf[MAX_FMTP_STR_LEN];

	    pj_ansi_snprintf(buf, MAX_FMTP_STR_LEN, "%.*s;octet-align=1",
			     (int)fmtp.fmt_param.slen, fmtp.fmt_param.ptr);
	    attr->value = pj_strdup3(pool, buf);
	}
    } else {
	/* Add new attribute for the AMR media format with octet-align 
	 * field set.
	 */
	char buf[MAX_FMTP_STR_LEN];

	attr = PJ_POOL_ZALLOC_T(pool, pjmedia_sdp_attr);
	attr->name = pj_str("fmtp");
	pj_ansi_snprintf(buf, MAX_FMTP_STR_LEN, "%.*s octet-align=1",
			 (int)media->desc.fmt[fmt_idx].slen,
		         media->desc.fmt[fmt_idx].ptr);
	attr->value = pj_strdup3(pool, buf);
	media->attr[media->attr_count++] = attr;
    }

    return PJ_SUCCESS;
}
示例#7
0
/* Matching G722.1 bitrates between offer and answer.
 */
static pj_bool_t match_g7221( const pjmedia_sdp_media *offer,
			      unsigned o_fmt_idx,
			      const pjmedia_sdp_media *answer,
			      unsigned a_fmt_idx)
{
    const pjmedia_sdp_attr *a_ans;
    const pjmedia_sdp_attr *a_off;
    pjmedia_sdp_fmtp fmtp;
    unsigned a_bitrate = 0, o_bitrate = 0;
    const pj_str_t bitrate = {"bitrate=", 8};
    const char *p;

    a_ans = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					 &answer->desc.fmt[a_fmt_idx]);
    if (!a_ans)
	return PJ_FALSE;

    if (pjmedia_sdp_attr_get_fmtp(a_ans, &fmtp) != PJ_SUCCESS)
	return PJ_FALSE;

    p = pj_stristr(&fmtp.fmt_param, &bitrate);
    if (p == NULL)
	return PJ_FALSE;

    a_bitrate = atoi(p + bitrate.slen);

    a_off = pjmedia_sdp_media_find_attr2(offer, "fmtp", 
					 &offer->desc.fmt[o_fmt_idx]);
    if (!a_off)
	return PJ_FALSE;

    if (pjmedia_sdp_attr_get_fmtp(a_off, &fmtp) != PJ_SUCCESS)
	return PJ_FALSE;

    p = pj_stristr(&fmtp.fmt_param, &bitrate);
    if (p == NULL)
	return PJ_FALSE;

    o_bitrate = atoi(p + bitrate.slen);

    return (a_bitrate == o_bitrate);
}
示例#8
0
/* Matching G722.1 bitrates between offer and answer.
 */
static pj_bool_t match_g7221( const pjmedia_sdp_media *offer,
			      unsigned o_fmt_idx,
			      const pjmedia_sdp_media *answer,
			      unsigned a_fmt_idx)
{
    const pjmedia_sdp_attr *attr_ans;
    const pjmedia_sdp_attr *attr_ofr;
    pjmedia_sdp_fmtp fmtp;
    unsigned a_bitrate, o_bitrate;
    const pj_str_t bitrate = {"bitrate=", 8};

    /* Parse offer */
    attr_ofr = pjmedia_sdp_media_find_attr2(offer, "fmtp", 
					    &offer->desc.fmt[o_fmt_idx]);
    if (!attr_ofr)
	return PJ_FALSE;

    if (pjmedia_sdp_attr_get_fmtp(attr_ofr, &fmtp) != PJ_SUCCESS)
	return PJ_FALSE;

    GET_FMTP_IVAL(o_bitrate, fmtp, bitrate, 0);

    /* Parse answer */
    attr_ans = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					    &answer->desc.fmt[a_fmt_idx]);
    if (!attr_ans)
	return PJ_FALSE;

    if (pjmedia_sdp_attr_get_fmtp(attr_ans, &fmtp) != PJ_SUCCESS)
	return PJ_FALSE;

    GET_FMTP_IVAL(a_bitrate, fmtp, bitrate, 0);

    /* Compare bitrate in answer and offer. */
    return (a_bitrate == o_bitrate);
}
示例#9
0
/*
 * Get fmtp mode parameter associated with the codec.
 */
static pj_status_t get_fmtp_mode(const pjmedia_sdp_media *m,
				 const pj_str_t *fmt,
				 int *p_mode)
{
    const pjmedia_sdp_attr *attr;
    pjmedia_sdp_fmtp fmtp;
    const pj_str_t str_mode = { "mode=", 5 };
    char *pos;

    /* Get "fmtp" attribute for the format */
    attr = pjmedia_sdp_media_find_attr2(m, "fmtp", fmt);
    if (attr == NULL)
	return -1;

    /* Parse "fmtp" attribute */
    if (pjmedia_sdp_attr_get_fmtp(attr, &fmtp) != PJ_SUCCESS)
	return -1;

    /* Look for "mode=" string in the fmtp */
    while (fmtp.fmt_param.slen >= str_mode.slen + 1) {
	if (pj_strnicmp(&fmtp.fmt_param, &str_mode, str_mode.slen)==0) {
	    /* Found "mode=" string */
	    break;
	}

	fmtp.fmt_param.ptr++;
	fmtp.fmt_param.slen--;
    }

    if (fmtp.fmt_param.slen < str_mode.slen + 1) {
	/* "mode=" param not found */
	return -1;
    }

    /* Get the mode */
    pos = fmtp.fmt_param.ptr + str_mode.slen;
    *p_mode = 0;
    while (pj_isdigit(*pos)) {
	*p_mode = *p_mode * 10 + (*pos - '0');
	++pos;
    }

    return PJ_SUCCESS;
}
示例#10
0
/* Try to match offer with answer. */
static pj_status_t match_offer(pj_pool_t *pool,
			       const pjmedia_sdp_media *offer,
			       const pjmedia_sdp_media *preanswer,
			       const pjmedia_sdp_media *orig_local,
			       pjmedia_sdp_media **p_answer)
{
    unsigned i;
    pj_bool_t offer_has_codec = 0,
	      offer_has_telephone_event = 0,
	      offer_has_other = 0,
	      found_matching_codec = 0,
	      found_matching_telephone_event = 0,
	      found_matching_other = 0;
    unsigned pt_answer_count = 0;
    pj_str_t pt_answer[PJMEDIA_MAX_SDP_FMT];
    pjmedia_sdp_media *answer;

    /* With the addition of telephone-event and dodgy MS RTC SDP, 
     * the answer generation algorithm looks really shitty...
     */
    for (i=0; i<offer->desc.fmt_count; ++i) {
	unsigned j;
	
	if (pj_isdigit(*offer->desc.fmt[i].ptr)) {
	    /* This is normal/standard payload type, where it's identified
	     * by payload number.
	     */
	    unsigned pt;

	    pt = pj_strtoul(&offer->desc.fmt[i]);
	    
	    if (pt < 96) {
		/* For static payload type, it's enough to compare just
		 * the payload number.
		 */

		offer_has_codec = 1;

		/* We just need to select one codec. 
		 * Continue if we have selected matching codec for previous 
		 * payload.
		 */
		if (found_matching_codec)
		    continue;

		/* Find matching codec in local descriptor. */
		for (j=0; j<preanswer->desc.fmt_count; ++j) {
		    unsigned p;
		    p = pj_strtoul(&preanswer->desc.fmt[j]);
		    if (p == pt && pj_isdigit(*preanswer->desc.fmt[j].ptr)) {
			found_matching_codec = 1;
			pt_answer[pt_answer_count++] = preanswer->desc.fmt[j];
			break;
		    }
		}

	    } else {
		/* This is dynamic payload type.
		 * For dynamic payload type, we must look the rtpmap and
		 * compare the encoding name.
		 */
		const pjmedia_sdp_attr *a;
		pjmedia_sdp_rtpmap or_;
		pj_bool_t is_codec;

		/* Get the rtpmap for the payload type in the offer. */
		a = pjmedia_sdp_media_find_attr2(offer, "rtpmap", 
						 &offer->desc.fmt[i]);
		if (!a) {
		    pj_assert(!"Bug! Offer should have been validated");
		    return PJMEDIA_SDP_EMISSINGRTPMAP;
		}
		pjmedia_sdp_attr_get_rtpmap(a, &or_);

		if (!pj_strcmp2(&or_.enc_name, "telephone-event")) {
		    offer_has_telephone_event = 1;
		    if (found_matching_telephone_event)
			continue;
		    is_codec = 0;
		} else {
		    offer_has_codec = 1;
		    if (found_matching_codec)
			continue;
		    is_codec = 1;
		}
		
		/* Find paylaod in our initial SDP with matching 
		 * encoding name and clock rate.
		 */
		for (j=0; j<preanswer->desc.fmt_count; ++j) {
		    a = pjmedia_sdp_media_find_attr2(preanswer, "rtpmap", 
						     &preanswer->desc.fmt[j]);
		    if (a) {
			pjmedia_sdp_rtpmap lr;
			pjmedia_sdp_attr_get_rtpmap(a, &lr);

			/* See if encoding name, clock rate, and
			 * channel count  match 
			 */
			if (!pj_stricmp(&or_.enc_name, &lr.enc_name) &&
			    or_.clock_rate == lr.clock_rate &&
			    (pj_strcmp(&or_.param, &lr.param)==0 ||
			     (or_.param.slen==1 && *or_.param.ptr=='1'))) 
			{
			    /* Match! */
			    if (is_codec) {
				/* Further check for G7221, negotiate bitrate. */
				if (pj_strcmp2(&or_.enc_name, "G7221")  == 0 &&
				    match_g7221(offer, i, preanswer, j) == 0)
				{
				    continue;
				}
				found_matching_codec = 1;
			    } else {
				found_matching_telephone_event = 1;
			    }

			    pt_answer[pt_answer_count++] = preanswer->desc.fmt[j];
			    break;
			}
		    }
		}
	    }

	} else {
	    /* This is a non-standard, brain damaged SDP where the payload
	     * type is non-numeric. It exists e.g. in Microsoft RTC based
	     * UA, to indicate instant messaging capability.
	     * Example:
	     *	- m=x-ms-message 5060 sip null
	     */
	    offer_has_other = 1;
	    if (found_matching_other)
		continue;

	    for (j=0; j<preanswer->desc.fmt_count; ++j) {
		if (!pj_strcmp(&offer->desc.fmt[i], &preanswer->desc.fmt[j])) {
		    /* Match */
		    found_matching_other = 1;
		    pt_answer[pt_answer_count++] = preanswer->desc.fmt[j];
		    break;
		}
	    }
	}
    }

    /* See if all types of offer can be matched. */
    if (offer_has_codec && !found_matching_codec) {
	return PJMEDIA_SDPNEG_NOANSCODEC;
    }

    /* If this comment is removed, negotiation will fail if remote has offered
       telephone-event and local is not configured with telephone-event

    if (offer_has_telephone_event && !found_matching_telephone_event) {
	return PJMEDIA_SDPNEG_NOANSTELEVENT;
    }
    */

    if (offer_has_other && !found_matching_other) {
	return PJMEDIA_SDPNEG_NOANSUNKNOWN;
    }

    /* Seems like everything is in order.
     * Build the answer by cloning from local media, but rearrange the payload
     * to suit the offer.
     */
    answer = pjmedia_sdp_media_clone(pool, orig_local);
    for (i=0; i<pt_answer_count; ++i) {
	unsigned j;
	for (j=i; j<answer->desc.fmt_count; ++j) {
	    if (!pj_strcmp(&answer->desc.fmt[j], &pt_answer[i]))
		break;
	}
	pj_assert(j != answer->desc.fmt_count);
	str_swap(&answer->desc.fmt[i], &answer->desc.fmt[j]);
    }
    
    /* Remove unwanted local formats. */
    for (i=pt_answer_count; i<answer->desc.fmt_count; ++i) {
	pjmedia_sdp_attr *a;

	/* Remove rtpmap for this format */
	a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", 
					 &answer->desc.fmt[i]);
	if (a) {
	    pjmedia_sdp_media_remove_attr(answer, a);
	}

	/* Remove fmtp for this format */
	a = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					 &answer->desc.fmt[i]);
	if (a) {
	    pjmedia_sdp_media_remove_attr(answer, a);
	}
    }
    answer->desc.fmt_count = pt_answer_count;

    /* If offer has zero port, set our answer with zero port too */
    if (offer->desc.port==0)
	answer->desc.port = 0;

    /* Update media direction. */
    update_media_direction(pool, offer, answer);

    *p_answer = answer;
    return PJ_SUCCESS;
}
示例#11
0
/* Update single local media description to after receiving answer
 * from remote.
 */
static pj_status_t process_m_answer( pj_pool_t *pool,
				     pjmedia_sdp_media *offer,
				     pjmedia_sdp_media *answer,
				     pj_bool_t allow_asym)
{
    unsigned i;

    /* Check that the media type match our offer. */

    if (pj_strcmp(&answer->desc.media, &offer->desc.media)!=0) {
	/* The media type in the answer is different than the offer! */
	return PJMEDIA_SDPNEG_EINVANSMEDIA;
    }


    /* Check that transport in the answer match our offer. */

    /* At this point, transport type must be compatible, 
     * the transport instance will do more validation later.
     */
    if (pjmedia_sdp_transport_cmp(&answer->desc.transport, 
				  &offer->desc.transport) 
	!= PJ_SUCCESS)
    {
	return PJMEDIA_SDPNEG_EINVANSTP;
    }


    /* Check if remote has rejected our offer */
    
    if (answer->desc.port == 0) {
	
	/* Remote has rejected our offer. 
	 * Set our port to zero too in active SDP.
	 */
	offer->desc.port = 0;
    }


    /* Process direction attributes */
    update_media_direction(pool, answer, offer);
 
    /* If asymetric media is allowed, then just check that remote answer has 
     * codecs that are within the offer. 
     *
     * Otherwise if asymetric media is not allowed, then we will choose only
     * one codec in our initial offer to match the answer.
     */
    if (allow_asym) {
	for (i=0; i<answer->desc.fmt_count; ++i) {
	    unsigned j;
	    pj_str_t *rem_fmt = &answer->desc.fmt[i];

	    for (j=0; j<offer->desc.fmt_count; ++j) {
		if (pj_strcmp(rem_fmt, &answer->desc.fmt[j])==0)
		    break;
	    }

	    if (j != offer->desc.fmt_count) {
		/* Found at least one common codec. */
		break;
	    }
	}

	if (i == answer->desc.fmt_count) {
	    /* No common codec in the answer! */
	    return PJMEDIA_SDPNEG_EANSNOMEDIA;
	}

	PJ_TODO(CHECK_SDP_NEGOTIATION_WHEN_ASYMETRIC_MEDIA_IS_ALLOWED);

    } else {
	/* Remove all format in the offer that has no matching answer */
	for (i=0; i<offer->desc.fmt_count;) {
	    unsigned pt;
	    pj_uint32_t j;
	    pj_str_t *fmt = &offer->desc.fmt[i];
	    

	    /* Find matching answer */
	    pt = pj_strtoul(fmt);

	    if (pt < 96) {
		for (j=0; j<answer->desc.fmt_count; ++j) {
		    if (pj_strcmp(fmt, &answer->desc.fmt[j])==0)
			break;
		}
	    } else {
		/* This is dynamic payload type.
		 * For dynamic payload type, we must look the rtpmap and
		 * compare the encoding name.
		 */
		const pjmedia_sdp_attr *a;
		pjmedia_sdp_rtpmap or_;

		/* Get the rtpmap for the payload type in the offer. */
		a = pjmedia_sdp_media_find_attr2(offer, "rtpmap", fmt);
		if (!a) {
		    pj_assert(!"Bug! Offer should have been validated");
		    return PJ_EBUG;
		}
		pjmedia_sdp_attr_get_rtpmap(a, &or_);

		/* Find paylaod in answer SDP with matching 
		 * encoding name and clock rate.
		 */
		for (j=0; j<answer->desc.fmt_count; ++j) {
		    a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", 
						     &answer->desc.fmt[j]);
		    if (a) {
			pjmedia_sdp_rtpmap ar;
			pjmedia_sdp_attr_get_rtpmap(a, &ar);

			/* See if encoding name, clock rate, and channel
			 * count match 
			 */
			if (!pj_stricmp(&or_.enc_name, &ar.enc_name) &&
			    or_.clock_rate == ar.clock_rate &&
			    (pj_stricmp(&or_.param, &ar.param)==0 ||
			     (ar.param.slen==1 && *ar.param.ptr=='1')))
			{
			    /* Further check for G7221, negotiate bitrate. */
			    if (pj_strcmp2(&or_.enc_name, "G7221") == 0) {
				if (match_g7221(offer, i, answer, j))
				    break;
			    } else {
				/* Match! */
				break;
			    }
			}
		    }
		}
	    }

	    if (j == answer->desc.fmt_count) {
		/* This format has no matching answer.
		 * Remove it from our offer.
		 */
		pjmedia_sdp_attr *a;

		/* Remove rtpmap associated with this format */
		a = pjmedia_sdp_media_find_attr2(offer, "rtpmap", fmt);
		if (a)
		    pjmedia_sdp_media_remove_attr(offer, a);

		/* Remove fmtp associated with this format */
		a = pjmedia_sdp_media_find_attr2(offer, "fmtp", fmt);
		if (a)
		    pjmedia_sdp_media_remove_attr(offer, a);

		/* Remove this format from offer's array */
		pj_array_erase(offer->desc.fmt, sizeof(offer->desc.fmt[0]),
			       offer->desc.fmt_count, i);
		--offer->desc.fmt_count;

	    } else {
		++i;
	    }
	}

	/* Arrange format in the offer so the order match the priority
	 * in the answer
	 */
	for (i=0; i<answer->desc.fmt_count; ++i) {
	    unsigned j;
	    pj_str_t *fmt = &answer->desc.fmt[i];

	    for (j=i; j<offer->desc.fmt_count; ++j) {
		if (pj_strcmp(fmt, &offer->desc.fmt[j])==0) {
		    str_swap(&offer->desc.fmt[i], &offer->desc.fmt[j]);
		    break;
		}
	    }
	}
    }

    /* Looks okay */
    return PJ_SUCCESS;
}
示例#12
0
/* Update media direction based on peer's media direction */
static void update_media_direction(pj_pool_t *pool,
				   const pjmedia_sdp_media *remote,
				   pjmedia_sdp_media *local)
{
    pjmedia_dir old_dir = PJMEDIA_DIR_ENCODING_DECODING,
	        new_dir;

    /* Get the media direction of local SDP */
    if (pjmedia_sdp_media_find_attr2(local, "sendonly", NULL))
	old_dir = PJMEDIA_DIR_ENCODING;
    else if (pjmedia_sdp_media_find_attr2(local, "recvonly", NULL))
	old_dir = PJMEDIA_DIR_DECODING;
    else if (pjmedia_sdp_media_find_attr2(local, "inactive", NULL))
	old_dir = PJMEDIA_DIR_NONE;

    new_dir = old_dir;

    /* Adjust local media direction based on remote media direction */
    if (pjmedia_sdp_media_find_attr2(remote, "inactive", NULL) != NULL) {
	/* If remote has "a=inactive", then local is inactive too */

	new_dir = PJMEDIA_DIR_NONE;

    } else if(pjmedia_sdp_media_find_attr2(remote, "sendonly", NULL) != NULL) {
	/* If remote has "a=sendonly", then set local to "recvonly" if
	 * it is currently "sendrecv". Otherwise if local is NOT "recvonly",
	 * then set local direction to "inactive".
	 */
	switch (old_dir) {
	case PJMEDIA_DIR_ENCODING_DECODING:
	    new_dir = PJMEDIA_DIR_DECODING;
	    break;
	case PJMEDIA_DIR_DECODING:
	    /* No change */
	    break;
	default:
	    new_dir = PJMEDIA_DIR_NONE;
	    break;
	}

    } else if(pjmedia_sdp_media_find_attr2(remote, "recvonly", NULL) != NULL) {
	/* If remote has "a=recvonly", then set local to "sendonly" if
	 * it is currently "sendrecv". Otherwise if local is NOT "sendonly",
	 * then set local direction to "inactive"
	 */
    
	switch (old_dir) {
	case PJMEDIA_DIR_ENCODING_DECODING:
	    new_dir = PJMEDIA_DIR_ENCODING;
	    break;
	case PJMEDIA_DIR_ENCODING:
	    /* No change */
	    break;
	default:
	    new_dir = PJMEDIA_DIR_NONE;
	    break;
	}

    } else {
	/* Remote indicates "sendrecv" capability. No change to local 
	 * direction 
	 */
    }

    if (new_dir != old_dir) {
	pjmedia_sdp_attr *a = NULL;

	remove_all_media_directions(local);

	switch (new_dir) {
	case PJMEDIA_DIR_NONE:
	    a = pjmedia_sdp_attr_create(pool, "inactive", NULL);
	    break;
	case PJMEDIA_DIR_ENCODING:
	    a = pjmedia_sdp_attr_create(pool, "sendonly", NULL);
	    break;
	case PJMEDIA_DIR_DECODING:
	    a = pjmedia_sdp_attr_create(pool, "recvonly", NULL);
	    break;
	default:
	    /* sendrecv */
	    break;
	}
	
	if (a) {
	    pjmedia_sdp_media_add_attr(local, a);
	}
    }
}
PJ_DEF(pj_status_t) pjmedia_codec_amr_match_sdp( pj_pool_t *pool,
						 pjmedia_sdp_media *offer,
						 unsigned o_fmt_idx,
						 pjmedia_sdp_media *answer,
						 unsigned a_fmt_idx,
						 unsigned option)
{
    /* Negotiated format-param field-names constants. */
    const pj_str_t STR_OCTET_ALIGN	= {"octet-align=", 12};
    const pj_str_t STR_CRC		= {"crc=", 4};
    const pj_str_t STR_ROBUST_SORTING	= {"robust-sorting=", 15};
    const pj_str_t STR_INTERLEAVING	= {"interleaving=", 13};

    /* Negotiated params and their default values. */
    unsigned a_octet_align = 0, o_octet_align = 0;
    unsigned a_crc = 0, o_crc = 0;
    unsigned a_robust_sorting = 0, o_robust_sorting = 0;
    unsigned a_interleaving = 0, o_interleaving = 0;

    const pjmedia_sdp_attr *attr_ans;
    const pjmedia_sdp_attr *attr_ofr;
    pjmedia_sdp_fmtp fmtp;
    pj_status_t status;

    /* Parse offerer FMTP */
    attr_ofr = pjmedia_sdp_media_find_attr2(offer, "fmtp", 
					    &offer->desc.fmt[o_fmt_idx]);
    if (attr_ofr) {
	status = pjmedia_sdp_attr_get_fmtp(attr_ofr, &fmtp);
	if (status != PJ_SUCCESS)
	    return status;

	GET_FMTP_IVAL(o_octet_align, fmtp, STR_OCTET_ALIGN, 0);
	GET_FMTP_IVAL(o_crc, fmtp, STR_CRC, 0);
	GET_FMTP_IVAL(o_robust_sorting, fmtp, STR_ROBUST_SORTING, 0);
	GET_FMTP_IVAL(o_interleaving, fmtp, STR_INTERLEAVING, 0);
    }

    /* Parse answerer FMTP */
    attr_ans = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					    &answer->desc.fmt[a_fmt_idx]);
    if (attr_ans) {
	status = pjmedia_sdp_attr_get_fmtp(attr_ans, &fmtp);
	if (status != PJ_SUCCESS)
	    return status;

	GET_FMTP_IVAL(a_octet_align, fmtp, STR_OCTET_ALIGN, 0);
	GET_FMTP_IVAL(a_crc, fmtp, STR_CRC, 0);
	GET_FMTP_IVAL(a_robust_sorting, fmtp, STR_ROBUST_SORTING, 0);
	GET_FMTP_IVAL(a_interleaving, fmtp, STR_INTERLEAVING, 0);
    }

    /* First, match crc, robust-sorting, interleaving settings */
    if (a_crc != o_crc ||
	a_robust_sorting != o_robust_sorting ||
	a_interleaving != o_interleaving)
    {
	return PJMEDIA_SDP_EFORMATNOTEQUAL;
    }

    /* Match octet-align setting */
    if (a_octet_align != o_octet_align) {
	/* Check if answer can be modified to match to the offer */
	if (option & PJMEDIA_SDP_NEG_FMT_MATCH_ALLOW_MODIFY_ANSWER) {
	    status = amr_toggle_octet_align(pool, answer, a_fmt_idx);
	    return status;
	} else {
	    return PJMEDIA_SDP_EFORMATNOTEQUAL;
	}
    }

    return PJ_SUCCESS;
}
示例#14
0
/*
 * Parse fmtp for specified format/payload type.
 */
static void parse_fmtp( pj_pool_t *pool,
			const pjmedia_sdp_media *m,
			unsigned pt,
			pjmedia_codec_fmtp *fmtp)
{
    const pjmedia_sdp_attr *attr;
    pjmedia_sdp_fmtp sdp_fmtp;
    char *p, *p_end, fmt_buf[8];
    pj_str_t fmt;

    pj_assert(m && fmtp);

    pj_bzero(fmtp, sizeof(pjmedia_codec_fmtp));

    /* Get "fmtp" attribute for the format */
    pj_ansi_sprintf(fmt_buf, "%d", pt);
    fmt = pj_str(fmt_buf);
    attr = pjmedia_sdp_media_find_attr2(m, "fmtp", &fmt);
    if (attr == NULL)
	return;

    /* Parse "fmtp" attribute */
    if (pjmedia_sdp_attr_get_fmtp(attr, &sdp_fmtp) != PJ_SUCCESS)
	return;

    /* Prepare parsing */
    p = sdp_fmtp.fmt_param.ptr;
    p_end = p + sdp_fmtp.fmt_param.slen;

    /* Parse */
    while (p < p_end) {
	char *token, *start, *end;

	/* Skip whitespaces */
	while (p < p_end && (*p == ' ' || *p == '\t')) ++p;
	if (p == p_end)
	    break;

	/* Get token */
	start = p;
	while (p < p_end && *p != ';' && *p != '=') ++p;
	end = p - 1;

	/* Right trim */
	while (end >= start && (*end == ' '  || *end == '\t' || 
				*end == '\r' || *end == '\n' ))
	    --end;

	/* Forward a char after trimming */
	++end;

	/* Store token */
	if (end > start) {
	    token = (char*)pj_pool_alloc(pool, end - start);
	    pj_ansi_strncpy(token, start, end - start);
	    if (*p == '=')
		/* Got param name */
		pj_strset(&fmtp->param[fmtp->cnt].name, token, end - start);
	    else
		/* Got param value */
		pj_strset(&fmtp->param[fmtp->cnt++].val, token, end - start);
	} else if (*p != '=') {
	    ++fmtp->cnt;
	}

	/* Next */
	++p;
    }
}
示例#15
0
/* Negotiate AMR format params between offer and answer. Format params
 * to be matched are: octet-align, crc, robust-sorting, interleaving, 
 * and channels (channels is negotiated by rtpmap line negotiation). 
 * Note: For answerer, octet-align mode setting is adaptable to offerer 
 *       setting. In the case that octet-align mode need to be adjusted,
 *       pt_need_adapt will be set to the format ID.
 *       
 */
static pj_bool_t match_amr( const pjmedia_sdp_media *offer,
			    unsigned o_fmt_idx,
			    const pjmedia_sdp_media *answer,
			    unsigned a_fmt_idx,
			    pj_bool_t answerer,
			    pj_str_t *pt_need_adapt)
{
    /* Negotiated format-param field-names constants. */
    const pj_str_t STR_OCTET_ALIGN	= {"octet-align=", 12};
    const pj_str_t STR_CRC		= {"crc=", 4};
    const pj_str_t STR_ROBUST_SORTING	= {"robust-sorting=", 15};
    const pj_str_t STR_INTERLEAVING	= {"interleaving=", 13};

    /* Negotiated params and their default values. */
    unsigned a_octet_align = 0, o_octet_align = 0;
    unsigned a_crc = 0, o_crc = 0;
    unsigned a_robust_sorting = 0, o_robust_sorting = 0;
    unsigned a_interleaving = 0, o_interleaving = 0;

    const pjmedia_sdp_attr *attr_ans;
    const pjmedia_sdp_attr *attr_ofr;
    pjmedia_sdp_fmtp fmtp;
    pj_bool_t match;

    /* Parse offerer FMTP */
    attr_ofr = pjmedia_sdp_media_find_attr2(offer, "fmtp", 
					    &offer->desc.fmt[o_fmt_idx]);
    if (attr_ofr) {
	if (pjmedia_sdp_attr_get_fmtp(attr_ofr, &fmtp) != PJ_SUCCESS)
	    /* Invalid fmtp format. */
	    return PJ_FALSE;

	GET_FMTP_IVAL(o_octet_align, fmtp, STR_OCTET_ALIGN, 0);
	GET_FMTP_IVAL(o_crc, fmtp, STR_CRC, 0);
	GET_FMTP_IVAL(o_robust_sorting, fmtp, STR_ROBUST_SORTING, 0);
	GET_FMTP_IVAL(o_interleaving, fmtp, STR_INTERLEAVING, 0);
    }

    /* Parse answerer FMTP */
    attr_ans = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					    &answer->desc.fmt[a_fmt_idx]);
    if (attr_ans) {
	if (pjmedia_sdp_attr_get_fmtp(attr_ans, &fmtp) != PJ_SUCCESS)
	    /* Invalid fmtp format. */
	    return PJ_FALSE;

	GET_FMTP_IVAL(a_octet_align, fmtp, STR_OCTET_ALIGN, 0);
	GET_FMTP_IVAL(a_crc, fmtp, STR_CRC, 0);
	GET_FMTP_IVAL(a_robust_sorting, fmtp, STR_ROBUST_SORTING, 0);
	GET_FMTP_IVAL(a_interleaving, fmtp, STR_INTERLEAVING, 0);
    }

    if (answerer) {
	match = a_crc == o_crc &&
		a_robust_sorting == o_robust_sorting &&
		a_interleaving == o_interleaving;

	/* If answerer octet-align setting doesn't match to the offerer's, 
	 * set pt_need_adapt to this media format ID to signal the caller
	 * that this format ID needs to be adjusted.
	 */
	if (a_octet_align != o_octet_align && match) {
	    pj_assert(pt_need_adapt != NULL);
	    *pt_need_adapt = answer->desc.fmt[a_fmt_idx];
	}
    } else {
	match = (a_octet_align == o_octet_align &&
		 a_crc == o_crc &&
		 a_robust_sorting == o_robust_sorting &&
		 a_interleaving == o_interleaving);
    }

    return match;
}
示例#16
0
static void get_codecs(struct ast_sip_session *session, const struct pjmedia_sdp_media *stream, struct ast_rtp_codecs *codecs,
       struct ast_sip_session_media *session_media)
{
	pjmedia_sdp_attr *attr;
	pjmedia_sdp_rtpmap *rtpmap;
	pjmedia_sdp_fmtp fmtp;
	struct ast_format *format;
	int i, num = 0, tel_event = 0;
	char name[256];
	char media[20];
	char fmt_param[256];
	enum ast_rtp_options options = session->endpoint->media.g726_non_standard ?
		AST_RTP_OPT_G726_NONSTANDARD : 0;

	ast_rtp_codecs_payloads_initialize(codecs);

	/* Iterate through provided formats */
	for (i = 0; i < stream->desc.fmt_count; ++i) {
		/* The payload is kept as a string for things like t38 but for video it is always numerical */
		ast_rtp_codecs_payloads_set_m_type(codecs, NULL, pj_strtoul(&stream->desc.fmt[i]));
		/* Look for the optional rtpmap attribute */
		if (!(attr = pjmedia_sdp_media_find_attr2(stream, "rtpmap", &stream->desc.fmt[i]))) {
			continue;
		}

		/* Interpret the attribute as an rtpmap */
		if ((pjmedia_sdp_attr_to_rtpmap(session->inv_session->pool_prov, attr, &rtpmap)) != PJ_SUCCESS) {
			continue;
		}

		ast_copy_pj_str(name, &rtpmap->enc_name, sizeof(name));
                if (strcmp(name,"telephone-event") == 0) {
                        tel_event++;
                }

		ast_copy_pj_str(media, (pj_str_t*)&stream->desc.media, sizeof(media));
		ast_rtp_codecs_payloads_set_rtpmap_type_rate(codecs, NULL, pj_strtoul(&stream->desc.fmt[i]),
							     media, name, options, rtpmap->clock_rate);
		/* Look for an optional associated fmtp attribute */
		if (!(attr = pjmedia_sdp_media_find_attr2(stream, "fmtp", &rtpmap->pt))) {
			continue;
		}

		if ((pjmedia_sdp_attr_get_fmtp(attr, &fmtp)) == PJ_SUCCESS) {
			ast_copy_pj_str(fmt_param, &fmtp.fmt, sizeof(fmt_param));
			if (sscanf(fmt_param, "%30d", &num) != 1) {
				continue;
			}

			if ((format = ast_rtp_codecs_get_payload_format(codecs, num))) {
				struct ast_format *format_parsed;

				ast_copy_pj_str(fmt_param, &fmtp.fmt_param, sizeof(fmt_param));

				format_parsed = ast_format_parse_sdp_fmtp(format, fmt_param);
				if (format_parsed) {
					ast_rtp_codecs_payload_replace_format(codecs, num, format_parsed);
					ao2_ref(format_parsed, -1);
				}

				ao2_ref(format, -1);
			}
		}
	}
	if ((tel_event==0) && (session->endpoint->dtmf == AST_SIP_DTMF_AUTO)) {
                ast_rtp_instance_dtmf_mode_set(session_media->rtp, AST_RTP_DTMF_MODE_INBAND);
	}
	/* Get the packetization, if it exists */
	if ((attr = pjmedia_sdp_media_find_attr2(stream, "ptime", NULL))) {
		unsigned long framing = pj_strtoul(pj_strltrim(&attr->value));
		if (framing && session->endpoint->media.rtp.use_ptime) {
			ast_rtp_codecs_set_framing(codecs, framing);
		}
	}
}
示例#17
0
/* Try to match offer with answer. */
static pj_status_t match_offer(pj_pool_t *pool,
			       pj_bool_t prefer_remote_codec_order,
                               pj_bool_t answer_with_multiple_codecs,
			       const pjmedia_sdp_media *offer,
			       const pjmedia_sdp_media *preanswer,
			       const pjmedia_sdp_session *preanswer_sdp,
			       pjmedia_sdp_media **p_answer)
{
    unsigned i;
    pj_bool_t master_has_codec = 0,
	      master_has_other = 0,
	      found_matching_codec = 0,
	      found_matching_telephone_event = 0,
	      found_matching_other = 0;
    unsigned pt_answer_count = 0;
    pj_str_t pt_answer[PJMEDIA_MAX_SDP_FMT];
    pj_str_t pt_offer[PJMEDIA_MAX_SDP_FMT];
    pjmedia_sdp_media *answer;
    const pjmedia_sdp_media *master, *slave;

    /* If offer has zero port, just clone the offer */
    if (offer->desc.port == 0) {
	answer = sdp_media_clone_deactivate(pool, offer, preanswer,
					    preanswer_sdp);
	*p_answer = answer;
	return PJ_SUCCESS;
    }

    /* If the preanswer define zero port, this media is being rejected,
     * just clone the preanswer.
     */
    if (preanswer->desc.port == 0) {
	answer = pjmedia_sdp_media_clone(pool, preanswer);
	*p_answer = answer;
	return PJ_SUCCESS;
    }

    /* Set master/slave negotiator based on prefer_remote_codec_order. */
    if (prefer_remote_codec_order) {
	master = offer;
	slave  = preanswer;
    } else {
	master = preanswer;
	slave  = offer;
    }
    
    /* With the addition of telephone-event and dodgy MS RTC SDP, 
     * the answer generation algorithm looks really shitty...
     */
    for (i=0; i<master->desc.fmt_count; ++i) {
	unsigned j;
	
	if (pj_isdigit(*master->desc.fmt[i].ptr)) {
	    /* This is normal/standard payload type, where it's identified
	     * by payload number.
	     */
	    unsigned pt;

	    pt = pj_strtoul(&master->desc.fmt[i]);
	    
	    if (pt < 96) {
		/* For static payload type, it's enough to compare just
		 * the payload number.
		 */

		master_has_codec = 1;

		/* We just need to select one codec if not allowing multiple.
		 * Continue if we have selected matching codec for previous 
		 * payload.
		 */
		if (!answer_with_multiple_codecs && found_matching_codec)
		    continue;

		/* Find matching codec in local descriptor. */
		for (j=0; j<slave->desc.fmt_count; ++j) {
		    unsigned p;
		    p = pj_strtoul(&slave->desc.fmt[j]);
		    if (p == pt && pj_isdigit(*slave->desc.fmt[j].ptr)) {
			found_matching_codec = 1;
			pt_offer[pt_answer_count] = slave->desc.fmt[j];
			pt_answer[pt_answer_count++] = slave->desc.fmt[j];
			break;
		    }
		}

	    } else {
		/* This is dynamic payload type.
		 * For dynamic payload type, we must look the rtpmap and
		 * compare the encoding name.
		 */
		const pjmedia_sdp_attr *a;
		pjmedia_sdp_rtpmap or_;
		pj_bool_t is_codec;

		/* Get the rtpmap for the payload type in the master. */
		a = pjmedia_sdp_media_find_attr2(master, "rtpmap", 
						 &master->desc.fmt[i]);
		if (!a) {
		    pj_assert(!"Bug! Offer should have been validated");
		    return PJMEDIA_SDP_EMISSINGRTPMAP;
		}
		pjmedia_sdp_attr_get_rtpmap(a, &or_);

		if (!pj_stricmp2(&or_.enc_name, "telephone-event")) {
		    if (found_matching_telephone_event)
			continue;
		    is_codec = 0;
		} else {
		    master_has_codec = 1;
		    if (!answer_with_multiple_codecs && found_matching_codec)
			continue;
		    is_codec = 1;
		}
		
		/* Find paylaod in our initial SDP with matching 
		 * encoding name and clock rate.
		 */
		for (j=0; j<slave->desc.fmt_count; ++j) {
		    a = pjmedia_sdp_media_find_attr2(slave, "rtpmap", 
						     &slave->desc.fmt[j]);
		    if (a) {
			pjmedia_sdp_rtpmap lr;
			pjmedia_sdp_attr_get_rtpmap(a, &lr);

			/* See if encoding name, clock rate, and
			 * channel count  match 
			 */
			if (!pj_stricmp(&or_.enc_name, &lr.enc_name) &&
			    or_.clock_rate == lr.clock_rate &&
			    (pj_stricmp(&or_.param, &lr.param)==0 ||
			     (lr.param.slen==0 && or_.param.slen==1 && 
						 *or_.param.ptr=='1') || 
			     (or_.param.slen==0 && lr.param.slen==1 && 
						  *lr.param.ptr=='1'))) 
			{
			    /* Match! */
			    if (is_codec) {
				pjmedia_sdp_media *o_med, *a_med;
				unsigned o_fmt_idx, a_fmt_idx;

				o_med = (pjmedia_sdp_media*)offer;
				a_med = (pjmedia_sdp_media*)preanswer;
				o_fmt_idx = prefer_remote_codec_order? i:j;
				a_fmt_idx = prefer_remote_codec_order? j:i;

				/* Call custom format matching callbacks */
				if (custom_fmt_match(pool, &or_.enc_name,
						     o_med, o_fmt_idx,
						     a_med, a_fmt_idx,
						     ALLOW_MODIFY_ANSWER) !=
				    PJ_SUCCESS)
				{
				    continue;
				}
				found_matching_codec = 1;
			    } else {
				found_matching_telephone_event = 1;
			    }

			    pt_offer[pt_answer_count] = 
						prefer_remote_codec_order?
						offer->desc.fmt[i]:
						offer->desc.fmt[j];
			    pt_answer[pt_answer_count++] = 
						prefer_remote_codec_order? 
						preanswer->desc.fmt[j]:
						preanswer->desc.fmt[i];
			    break;
			}
		    }
		}
	    }

	} else {
	    /* This is a non-standard, brain damaged SDP where the payload
	     * type is non-numeric. It exists e.g. in Microsoft RTC based
	     * UA, to indicate instant messaging capability.
	     * Example:
	     *	- m=x-ms-message 5060 sip null
	     */
	    master_has_other = 1;
	    if (found_matching_other)
		continue;

	    for (j=0; j<slave->desc.fmt_count; ++j) {
		if (!pj_strcmp(&master->desc.fmt[i], &slave->desc.fmt[j])) {
		    /* Match */
		    found_matching_other = 1;
		    pt_offer[pt_answer_count] = prefer_remote_codec_order?
						offer->desc.fmt[i]:
						offer->desc.fmt[j];
		    pt_answer[pt_answer_count++] = prefer_remote_codec_order? 
						   preanswer->desc.fmt[j]:
						   preanswer->desc.fmt[i];
		    break;
		}
	    }
	}
    }

    /* See if all types of master can be matched. */
    if (master_has_codec && !found_matching_codec) {
	return PJMEDIA_SDPNEG_NOANSCODEC;
    }

    /* If this comment is removed, negotiation will fail if remote has offered
       telephone-event and local is not configured with telephone-event

    if (offer_has_telephone_event && !found_matching_telephone_event) {
	return PJMEDIA_SDPNEG_NOANSTELEVENT;
    }
    */

    if (master_has_other && !found_matching_other) {
	return PJMEDIA_SDPNEG_NOANSUNKNOWN;
    }

    /* Seems like everything is in order.
     * Build the answer by cloning from preanswer, but rearrange the payload
     * to suit the offer.
     */
    answer = pjmedia_sdp_media_clone(pool, preanswer);
    for (i=0; i<pt_answer_count; ++i) {
	unsigned j;
	for (j=i; j<answer->desc.fmt_count; ++j) {
	    if (!pj_strcmp(&answer->desc.fmt[j], &pt_answer[i]))
		break;
	}
	pj_assert(j != answer->desc.fmt_count);
	str_swap(&answer->desc.fmt[i], &answer->desc.fmt[j]);
    }
    
    /* Remove unwanted local formats. */
    for (i=pt_answer_count; i<answer->desc.fmt_count; ++i) {
	pjmedia_sdp_attr *a;

	/* Remove rtpmap for this format */
	a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", 
					 &answer->desc.fmt[i]);
	if (a) {
	    pjmedia_sdp_media_remove_attr(answer, a);
	}

	/* Remove fmtp for this format */
	a = pjmedia_sdp_media_find_attr2(answer, "fmtp", 
					 &answer->desc.fmt[i]);
	if (a) {
	    pjmedia_sdp_media_remove_attr(answer, a);
	}
    }
    answer->desc.fmt_count = pt_answer_count;

#if PJMEDIA_SDP_NEG_ANSWER_SYMMETRIC_PT
    apply_answer_symmetric_pt(pool, answer, pt_answer_count,
			      pt_offer, pt_answer);
#endif

    /* Update media direction. */
    update_media_direction(pool, offer, answer);

    *p_answer = answer;
    return PJ_SUCCESS;
}
示例#18
0
/*! \brief Function which processes ICE attributes in an audio stream */
static void process_ice_attributes(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
				   const struct pjmedia_sdp_session *remote, const struct pjmedia_sdp_media *remote_stream)
{
	struct ast_rtp_engine_ice *ice;
	const pjmedia_sdp_attr *attr;
	char attr_value[256];
	unsigned int attr_i;

	/* If ICE support is not enabled or available exit early */
	if (!session->endpoint->media.rtp.ice_support || !(ice = ast_rtp_instance_get_ice(session_media->rtp))) {
		return;
	}

	attr = pjmedia_sdp_media_find_attr2(remote_stream, "ice-ufrag", NULL);
	if (!attr) {
		attr = pjmedia_sdp_attr_find2(remote->attr_count, remote->attr, "ice-ufrag", NULL);
	}
	if (attr) {
		ast_copy_pj_str(attr_value, (pj_str_t*)&attr->value, sizeof(attr_value));
		ice->set_authentication(session_media->rtp, attr_value, NULL);
	} else {
		return;
	}

	attr = pjmedia_sdp_media_find_attr2(remote_stream, "ice-pwd", NULL);
	if (!attr) {
		attr = pjmedia_sdp_attr_find2(remote->attr_count, remote->attr, "ice-pwd", NULL);
	}
	if (attr) {
		ast_copy_pj_str(attr_value, (pj_str_t*)&attr->value, sizeof(attr_value));
		ice->set_authentication(session_media->rtp, NULL, attr_value);
	} else {
		return;
	}

	if (pjmedia_sdp_media_find_attr2(remote_stream, "ice-lite", NULL)) {
		ice->ice_lite(session_media->rtp);
	}

	/* Find all of the candidates */
	for (attr_i = 0; attr_i < remote_stream->attr_count; ++attr_i) {
		char foundation[32], transport[32], address[PJ_INET6_ADDRSTRLEN + 1], cand_type[6], relay_address[PJ_INET6_ADDRSTRLEN + 1] = "";
		unsigned int port, relay_port = 0;
		struct ast_rtp_engine_ice_candidate candidate = { 0, };

		attr = remote_stream->attr[attr_i];

		/* If this is not a candidate line skip it */
		if (pj_strcmp2(&attr->name, "candidate")) {
			continue;
		}

		ast_copy_pj_str(attr_value, (pj_str_t*)&attr->value, sizeof(attr_value));

		if (sscanf(attr_value, "%31s %30u %31s %30u %46s %30u typ %5s %*s %23s %*s %30u", foundation, &candidate.id, transport,
			(unsigned *)&candidate.priority, address, &port, cand_type, relay_address, &relay_port) < 7) {
			/* Candidate did not parse properly */
			continue;
		}

		candidate.foundation = foundation;
		candidate.transport = transport;

		ast_sockaddr_parse(&candidate.address, address, PARSE_PORT_FORBID);
		ast_sockaddr_set_port(&candidate.address, port);

		if (!strcasecmp(cand_type, "host")) {
			candidate.type = AST_RTP_ICE_CANDIDATE_TYPE_HOST;
		} else if (!strcasecmp(cand_type, "srflx")) {
			candidate.type = AST_RTP_ICE_CANDIDATE_TYPE_SRFLX;
		} else if (!strcasecmp(cand_type, "relay")) {
			candidate.type = AST_RTP_ICE_CANDIDATE_TYPE_RELAYED;
		} else {
			continue;
		}

		if (!ast_strlen_zero(relay_address)) {
			ast_sockaddr_parse(&candidate.relay_address, relay_address, PARSE_PORT_FORBID);
		}

		if (relay_port) {
			ast_sockaddr_set_port(&candidate.relay_address, relay_port);
		}

		ice->add_remote_candidate(session_media->rtp, &candidate);
	}

	ice->set_role(session_media->rtp, pjmedia_sdp_neg_was_answer_remote(session->inv_session->neg) == PJ_TRUE ?
		AST_RTP_ICE_ROLE_CONTROLLING : AST_RTP_ICE_ROLE_CONTROLLED);
	ice->start(session_media->rtp);
}
示例#19
0
/* Update single local media description to after receiving answer
 * from remote.
 */
static pj_status_t process_m_answer( pj_pool_t *pool,
				     pjmedia_sdp_media *offer,
				     pjmedia_sdp_media *answer,
				     pj_bool_t allow_asym)
{
    unsigned i;

    /* Check that the media type match our offer. */

    if (pj_strcmp(&answer->desc.media, &offer->desc.media)!=0) {
	/* The media type in the answer is different than the offer! */
	return PJMEDIA_SDPNEG_EINVANSMEDIA;
    }


    /* Check that transport in the answer match our offer. */

    /* At this point, transport type must be compatible, 
     * the transport instance will do more validation later.
     */
    if (pjmedia_sdp_transport_cmp(&answer->desc.transport, 
				  &offer->desc.transport) 
	!= PJ_SUCCESS)
    {
	return PJMEDIA_SDPNEG_EINVANSTP;
    }


    /* Check if remote has rejected our offer */
    if (answer->desc.port == 0) {
	
	/* Remote has rejected our offer. 
	 * Deactivate our media too.
	 */
	pjmedia_sdp_media_deactivate(pool, offer);

	/* Don't need to proceed */
	return PJ_SUCCESS;
    }

    /* Ticket #1148: check if remote answer does not set port to zero when
     * offered with port zero. Let's just tolerate it.
     */
    if (offer->desc.port == 0) {
	/* Don't need to proceed */
	return PJ_SUCCESS;
    }

    /* Process direction attributes */
    update_media_direction(pool, answer, offer);
 
    /* If asymetric media is allowed, then just check that remote answer has 
     * codecs that are within the offer. 
     *
     * Otherwise if asymetric media is not allowed, then we will choose only
     * one codec in our initial offer to match the answer.
     */
    if (allow_asym) {
	for (i=0; i<answer->desc.fmt_count; ++i) {
	    unsigned j;
	    pj_str_t *rem_fmt = &answer->desc.fmt[i];

	    for (j=0; j<offer->desc.fmt_count; ++j) {
		if (pj_strcmp(rem_fmt, &answer->desc.fmt[j])==0)
		    break;
	    }

	    if (j != offer->desc.fmt_count) {
		/* Found at least one common codec. */
		break;
	    }
	}

	if (i == answer->desc.fmt_count) {
	    /* No common codec in the answer! */
	    return PJMEDIA_SDPNEG_EANSNOMEDIA;
	}

	PJ_TODO(CHECK_SDP_NEGOTIATION_WHEN_ASYMETRIC_MEDIA_IS_ALLOWED);

    } else {
	/* Offer format priority based on answer format index/priority */
	unsigned offer_fmt_prior[PJMEDIA_MAX_SDP_FMT];

	/* Remove all format in the offer that has no matching answer */
	for (i=0; i<offer->desc.fmt_count;) {
	    unsigned pt;
	    pj_uint32_t j;
	    pj_str_t *fmt = &offer->desc.fmt[i];
	    

	    /* Find matching answer */
	    pt = pj_strtoul(fmt);

	    if (pt < 96) {
		for (j=0; j<answer->desc.fmt_count; ++j) {
		    if (pj_strcmp(fmt, &answer->desc.fmt[j])==0)
			break;
		}
	    } else {
		/* This is dynamic payload type.
		 * For dynamic payload type, we must look the rtpmap and
		 * compare the encoding name.
		 */
		const pjmedia_sdp_attr *a;
		pjmedia_sdp_rtpmap or_;

		/* Get the rtpmap for the payload type in the offer. */
		a = pjmedia_sdp_media_find_attr2(offer, "rtpmap", fmt);
		if (!a) {
		    pj_assert(!"Bug! Offer should have been validated");
		    return PJ_EBUG;
		}
		pjmedia_sdp_attr_get_rtpmap(a, &or_);

		/* Find paylaod in answer SDP with matching 
		 * encoding name and clock rate.
		 */
		for (j=0; j<answer->desc.fmt_count; ++j) {
		    a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", 
						     &answer->desc.fmt[j]);
		    if (a) {
			pjmedia_sdp_rtpmap ar;
			pjmedia_sdp_attr_get_rtpmap(a, &ar);

			/* See if encoding name, clock rate, and channel
			 * count match 
			 */
			if (!pj_stricmp(&or_.enc_name, &ar.enc_name) &&
			    or_.clock_rate == ar.clock_rate &&
			    (pj_stricmp(&or_.param, &ar.param)==0 ||
			     (ar.param.slen==1 && *ar.param.ptr=='1')))
			{
			    /* Call custom format matching callbacks */
			    if (custom_fmt_match(pool, &or_.enc_name,
						 offer, i, answer, j, 0) ==
				PJ_SUCCESS)
			    {
				/* Match! */
				break;
			    }
			}
		    }
		}
	    }

	    if (j == answer->desc.fmt_count) {
		/* This format has no matching answer.
		 * Remove it from our offer.
		 */
		pjmedia_sdp_attr *a;

		/* Remove rtpmap associated with this format */
		a = pjmedia_sdp_media_find_attr2(offer, "rtpmap", fmt);
		if (a)
		    pjmedia_sdp_media_remove_attr(offer, a);

		/* Remove fmtp associated with this format */
		a = pjmedia_sdp_media_find_attr2(offer, "fmtp", fmt);
		if (a)
		    pjmedia_sdp_media_remove_attr(offer, a);

		/* Remove this format from offer's array */
		pj_array_erase(offer->desc.fmt, sizeof(offer->desc.fmt[0]),
			       offer->desc.fmt_count, i);
		--offer->desc.fmt_count;

	    } else {
		offer_fmt_prior[i] = j;
		++i;
	    }
	}

	if (0 == offer->desc.fmt_count) {
	    /* No common codec in the answer! */
	    return PJMEDIA_SDPNEG_EANSNOMEDIA;
	}

	/* Post process:
	 * - Resort offer formats so the order match to the answer.
	 * - Remove answer formats that unmatches to the offer.
	 */
	
	/* Resort offer formats */
	for (i=0; i<offer->desc.fmt_count; ++i) {
	    unsigned j;
	    for (j=i+1; j<offer->desc.fmt_count; ++j) {
		if (offer_fmt_prior[i] > offer_fmt_prior[j]) {
		    unsigned tmp = offer_fmt_prior[i];
		    offer_fmt_prior[i] = offer_fmt_prior[j];
		    offer_fmt_prior[j] = tmp;
		    str_swap(&offer->desc.fmt[i], &offer->desc.fmt[j]);
		}
	    }
	}

	/* Remove unmatched answer formats */
	{
	    unsigned del_cnt = 0;
	    for (i=0; i<answer->desc.fmt_count;) {
		/* The offer is ordered now, also the offer_fmt_prior */
		if (i >= offer->desc.fmt_count || 
		    offer_fmt_prior[i]-del_cnt != i)
		{
		    pj_str_t *fmt = &answer->desc.fmt[i];
		    pjmedia_sdp_attr *a;

		    /* Remove rtpmap associated with this format */
		    a = pjmedia_sdp_media_find_attr2(answer, "rtpmap", fmt);
		    if (a)
			pjmedia_sdp_media_remove_attr(answer, a);

		    /* Remove fmtp associated with this format */
		    a = pjmedia_sdp_media_find_attr2(answer, "fmtp", fmt);
		    if (a)
			pjmedia_sdp_media_remove_attr(answer, a);

		    /* Remove this format from answer's array */
		    pj_array_erase(answer->desc.fmt, 
				   sizeof(answer->desc.fmt[0]),
				   answer->desc.fmt_count, i);
		    --answer->desc.fmt_count;

		    ++del_cnt;
		} else {
		    ++i;
		}
	    }
	}
    }

    /* Looks okay */
    return PJ_SUCCESS;
}