PJ_DEF(pjmedia_sdp_media*) pjmedia_sdp_media_clone_deactivate(
pj_pool_t *pool,
const pjmedia_sdp_media *rhs)
{
unsigned int i;
pjmedia_sdp_media *m;
PJ_ASSERT_RETURN(pool && rhs, NULL);
m = PJ_POOL_ZALLOC_T(pool, pjmedia_sdp_media);
pj_memcpy(m, rhs, sizeof(*m));
/* Clone the media line only */
pj_strdup (pool, &m->desc.media, &rhs->desc.media);
pj_strdup (pool, &m->desc.transport, &rhs->desc.transport);
for (i=0; i<rhs->desc.fmt_count; ++i)
pj_strdup(pool, &m->desc.fmt[i], &rhs->desc.fmt[i]);
if (rhs->conn) {
m->conn = pjmedia_sdp_conn_clone (pool, rhs->conn);
PJ_ASSERT_RETURN(m->conn != NULL, NULL);
}
m->bandw_count = rhs->bandw_count;
for (i=0; i < rhs->bandw_count; ++i) {
m->bandw[i] = pjmedia_sdp_bandw_clone (pool, rhs->bandw[i]);
PJ_ASSERT_RETURN(m->bandw[i] != NULL, NULL);
}
/* And deactivate it */
pjmedia_sdp_media_deactivate(pool, m);
return m;
}
static pj_status_t transport_encode_sdp(pjmedia_transport *tp,
pj_pool_t *pool,
pjmedia_sdp_session *sdp_local,
const pjmedia_sdp_session *rem_sdp,
unsigned media_index)
{
struct transport_udp *udp = (struct transport_udp*)tp;
/* Validate media transport */
/* By now, this transport only support RTP/AVP transport */
if ((udp->media_options & PJMEDIA_TPMED_NO_TRANSPORT_CHECKING) == 0) {
pjmedia_sdp_media *m_rem, *m_loc;
m_rem = rem_sdp? rem_sdp->media[media_index] : NULL;
m_loc = sdp_local->media[media_index];
if (pj_stricmp(&m_loc->desc.transport, &ID_RTP_AVP) ||
(m_rem && pj_stricmp(&m_rem->desc.transport, &ID_RTP_AVP)))
{
pjmedia_sdp_media_deactivate(pool, m_loc);
return PJMEDIA_SDP_EINPROTO;
}
}
return PJ_SUCCESS;
}
static pj_status_t transport_encode_sdp(pjmedia_transport *tp,
pj_pool_t *sdp_pool,
pjmedia_sdp_session *sdp_local,
const pjmedia_sdp_session *rem_sdp,
unsigned media_index)
{
struct transport_ice *tp_ice = (struct transport_ice*)tp;
pj_status_t status;
/* Validate media transport */
/* For now, this transport only support RTP/AVP transport */
if ((tp_ice->media_option & PJMEDIA_TPMED_NO_TRANSPORT_CHECKING) == 0) {
pjmedia_sdp_media *loc_m, *rem_m;
rem_m = rem_sdp? rem_sdp->media[media_index] : NULL;
loc_m = sdp_local->media[media_index];
if (pj_stricmp(&loc_m->desc.transport, &STR_RTP_AVP) ||
(rem_m && pj_stricmp(&rem_m->desc.transport, &STR_RTP_AVP)))
{
pjmedia_sdp_media_deactivate(sdp_pool, loc_m);
return PJMEDIA_SDP_EINPROTO;
}
}
if (tp_ice->initial_sdp) {
if (rem_sdp) {
status = create_initial_answer(tp_ice, sdp_pool, sdp_local,
rem_sdp, media_index);
} else {
status = create_initial_offer(tp_ice, sdp_pool, sdp_local,
media_index);
}
} else {
if (rem_sdp) {
status = create_subsequent_answer(tp_ice, sdp_pool, sdp_local,
rem_sdp, media_index);
} else {
status = create_subsequent_offer(tp_ice, sdp_pool, sdp_local,
media_index);
}
}
if (status==PJ_SUCCESS) {
if (rem_sdp)
tp_ice->oa_role = ROLE_ANSWERER;
else
tp_ice->oa_role = ROLE_OFFERER;
}
return status;
}
/* Update local media session (offer) to create active local session
* after receiving remote answer.
*/
static pj_status_t process_answer(pj_pool_t *pool,
pjmedia_sdp_session *offer,
pjmedia_sdp_session *answer,
pj_bool_t allow_asym,
pjmedia_sdp_session **p_active)
{
unsigned omi = 0; /* Offer media index */
unsigned ami = 0; /* Answer media index */
pj_bool_t has_active = PJ_FALSE;
pj_status_t status;
/* Check arguments. */
PJ_ASSERT_RETURN(pool && offer && answer && p_active, PJ_EINVAL);
/* Check that media count match between offer and answer */
// Ticket #527, different media count is allowed for more interoperability,
// however, the media order must be same between offer and answer.
// if (offer->media_count != answer->media_count)
// return PJMEDIA_SDPNEG_EMISMEDIA;
/* Now update each media line in the offer with the answer. */
for (; omi<offer->media_count; ++omi) {
if (ami == answer->media_count) {
/* The answer has less media than the offer */
pjmedia_sdp_media *am;
/* Generate matching-but-disabled-media for the answer */
am = sdp_media_clone_deactivate(pool, offer->media[omi],
offer->media[omi], offer);
answer->media[answer->media_count++] = am;
++ami;
/* Deactivate our media offer too */
pjmedia_sdp_media_deactivate(pool, offer->media[omi]);
/* No answer media to be negotiated */
continue;
}
status = process_m_answer(pool, offer->media[omi], answer->media[ami],
allow_asym);
/* If media type is mismatched, just disable the media. */
if (status == PJMEDIA_SDPNEG_EINVANSMEDIA) {
pjmedia_sdp_media_deactivate(pool, offer->media[omi]);
continue;
}
/* No common format in the answer media. */
else if (status == PJMEDIA_SDPNEG_EANSNOMEDIA) {
pjmedia_sdp_media_deactivate(pool, offer->media[omi]);
pjmedia_sdp_media_deactivate(pool, answer->media[ami]);
}
/* Return the error code, for other errors. */
else if (status != PJ_SUCCESS) {
return status;
}
if (offer->media[omi]->desc.port != 0)
has_active = PJ_TRUE;
++ami;
}
*p_active = offer;
return has_active ? PJ_SUCCESS : PJMEDIA_SDPNEG_ENOMEDIA;
}
/* 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;
}
