/* v=0 o=mhandley 2890844526 2890842807 IN IP4 126.16.64.4 s=SDP Seminar i=A Seminar on the session description protocol u=http://www.cs.ucl.ac.uk/staff/M.Handley/sdp.03.ps [email protected] (Mark Handley) c=IN IP4 224.2.17.12/127 t=2873397496 2873404696 a=recvonly m=audio 3456 RTP/AVP 0 m=video 2232 RTP/AVP 31 m=whiteboard 32416 UDP WB a=orient:portrait */ int rtsp_client_sdp(struct rtsp_client_t* rtsp, const char* content) { int i, j, n, count; int formats[N_MEDIA_FORMAT]; struct rtsp_media_t* media; void* sdp; sdp = sdp_parse(content); if (!sdp) return -1; count = sdp_media_count(sdp); if(count > N_MEDIA) { rtsp->media_ptr = (struct rtsp_media_t*)malloc(sizeof(struct rtsp_media_t)*(count-N_MEDIA)); if(!rtsp->media_ptr) { sdp_destroy(sdp); return ENOMEM; } memset(rtsp->media_ptr, 0, sizeof(struct rtsp_media_t)*(count-N_MEDIA)); } rtsp->media_count = count; // rfc 2326 C.1.1 Control URL (p80) // If found at the session level, the attribute indicates the URL for aggregate control rtsp->aggregate = rtsp_media_aggregate_control_enable(sdp); rtsp_get_session_uri(sdp, rtsp->aggregate_uri, sizeof(rtsp->aggregate_uri), rtsp->uri, rtsp->baseuri, rtsp->location); for(i = 0; i < count; i++) { media = rtsp_get_media(rtsp, i); //media->cseq = rand(); // RTSP2326 C.1.1 Control URL rtsp_get_media_uri(sdp, i, media->uri, sizeof(media->uri), rtsp->aggregate_uri); n = sdp_media_formats(sdp, i, formats, N_MEDIA_FORMAT); media->avformat_count = n > N_MEDIA_FORMAT ? N_MEDIA_FORMAT : n; for(j = 0; j < media->avformat_count; j++) { media->avformats[j].fmt = formats[j]; } // update media encoding sdp_media_attribute_list(sdp, i, NULL, rtsp_media_onattr, media); } sdp_destroy(sdp); return 0; }
/* v=0 o=mhandley 2890844526 2890842807 IN IP4 126.16.64.4 s=SDP Seminar i=A Seminar on the session description protocol u=http://www.cs.ucl.ac.uk/staff/M.Handley/sdp.03.ps [email protected] (Mark Handley) c=IN IP4 224.2.17.12/127 t=2873397496 2873404696 a=recvonly m=audio 3456 RTP/AVP 0 m=video 2232 RTP/AVP 31 m=whiteboard 32416 UDP WB a=orient:portrait */ int rtsp_client_sdp(struct rtsp_client_context_t* ctx, void* sdp) { int i, count; int formats[N_MEDIA_FORMAT]; struct rtsp_media_t* media; assert(sdp); count = sdp_media_count(sdp); if(count > N_MEDIA) { ctx->media_ptr = (struct rtsp_media_t*)malloc(sizeof(struct rtsp_media_t)*(count-N_MEDIA)); if(!ctx->media_ptr) return -1; memset(ctx->media_ptr, 0, sizeof(struct rtsp_media_t)*(count-N_MEDIA)); } ctx->media_count = count; // rfc 2326 C.1.1 Control URL (p80) // If found at the session level, the attribute indicates the URL for aggregate control ctx->aggregate = rtsp_media_aggregate_control_enable(sdp); rtsp_get_session_uri(sdp, ctx->aggregate_uri, sizeof(ctx->aggregate_uri), ctx->uri, ctx->baseuri, ctx->location); for(i = 0; i < count; i++) { int j, n; media = rtsp_get_media(ctx, i); media->cseq = rand(); // RTSP2326 C.1.1 Control URL rtsp_get_media_uri(sdp, i, media->uri, sizeof(media->uri), ctx->aggregate_uri); n = sdp_media_formats(sdp, i, formats, N_MEDIA_FORMAT); media->avformat_count = n > N_MEDIA_FORMAT ? N_MEDIA_FORMAT : n; for(j = 0; j < media->avformat_count; j++) { media->avformats[j].pt = formats[j]; } // update media encoding sdp_media_attribute_list(sdp, i, NULL, rtsp_media_onattr, media); } return 0; }
/** Upgrade m= lines within session */
static
int soa_sdp_upgrade(soa_session_t *ss,
su_home_t *home,
sdp_session_t *session,
sdp_session_t const *user,
sdp_session_t const *remote,
int **return_u2s,
int **return_s2u)
{
soa_static_session_t *sss = (soa_static_session_t *)ss;
int Ns, Nu, Nr, Nmax, n, i, j;
sdp_media_t *m, **mm, *um;
sdp_media_t **s_media, **o_media, **u_media;
sdp_media_t const *rm, **r_media;
int *u2s = NULL, *s2u = NULL;
if (session == NULL || user == NULL)
return (errno = EFAULT), -1;
Ns = sdp_media_count(session, sdp_media_any, (sdp_text_t)0, (sdp_proto_e)0, (sdp_text_t)0);
Nu = sdp_media_count(user, sdp_media_any, (sdp_text_t)0, (sdp_proto_e)0, (sdp_text_t)0);
Nr = sdp_media_count(remote, sdp_media_any, (sdp_text_t)0, (sdp_proto_e)0, (sdp_text_t)0);
if (remote == NULL)
Nmax = Ns + Nu;
else if (Ns < Nr)
Nmax = Nr;
else
Nmax = Ns;
s_media = su_zalloc(home, (Nmax + 1) * (sizeof *s_media));
o_media = su_zalloc(home, (Ns + 1) * (sizeof *o_media));
u_media = su_zalloc(home, (Nu + 1) * (sizeof *u_media));
r_media = su_zalloc(home, (Nr + 1) * (sizeof *r_media));
if (!s_media || !o_media || !u_media || !r_media)
return -1;
um = sdp_media_dup_all(home, user->sdp_media, session);
if (!um && user->sdp_media)
return -1;
u2s = su_alloc(home, (Nu + 1) * sizeof(*u2s));
s2u = su_alloc(home, (Nmax + 1) * sizeof(*s2u));
if (!u2s || !s2u)
return -1;
for (i = 0; i < Nu; i++)
u2s[i] = U2S_NOT_USED;
u2s[Nu] = U2S_SENTINEL;
for (i = 0; i < Nmax; i++)
s2u[i] = U2S_NOT_USED;
s2u[Nmax] = U2S_SENTINEL;
for (i = 0, m = session->sdp_media; m && i < Ns; m = m->m_next)
o_media[i++] = m;
assert(i == Ns);
for (i = 0, m = um; m && i < Nu; m = m->m_next)
u_media[i++] = m;
assert(i == Nu);
m = remote ? remote->sdp_media : NULL;
for (i = 0; m && i < Nr; m = m->m_next)
r_media[i++] = m;
assert(i == Nr);
if (sss->sss_ordered_user && sss->sss_u2s) { /* User SDP is ordered */
for (j = 0; sss->sss_u2s[j] != U2S_SENTINEL; j++) {
i = sss->sss_u2s[j];
if (i == U2S_NOT_USED)
continue;
if (j >= Nu) /* lines removed from user SDP */
continue;
if (i >= Ns) /* I should never be called but somehow i and Ns are 0 here sometimes */
continue;
s_media[i] = u_media[j], u_media[j] = SDP_MEDIA_NONE;
u2s[j] = i, s2u[i] = j;
}
}
if (remote) {
/* Update session according to remote */
for (i = 0; i < Nr; i++) {
rm = r_media[i];
m = s_media[i];
if (!m) {
int codec_mismatch = 0;
if (!rm->m_rejected)
j = soa_sdp_matching_mindex(ss, u_media, rm, &codec_mismatch);
else
j = -1;
if (j == -1) {
s_media[i] = soa_sdp_make_rejected_media(home, rm, session, 0);
continue;
}
else if (codec_mismatch && !ss->ss_rtp_mismatch) {
m = soa_sdp_make_rejected_media(home, u_media[j], session, 1);
soa_sdp_set_rtpmap_pt(s_media[i] = m, rm);
continue;
}
s_media[i] = m = u_media[j]; u_media[j] = SDP_MEDIA_NONE;
u2s[j] = i, s2u[i] = j;
}
if (sdp_media_uses_rtp(rm))
soa_sdp_media_upgrade_rtpmaps(ss, m, rm);
}
}
else {
if (sss->sss_ordered_user) {
/* Update session with unused media in u_media */
if (!sss->sss_reuse_rejected) {
/* Mark previously used slots */
for (i = 0; i < Ns; i++) {
if (s_media[i])
continue;
s_media[i] =
soa_sdp_make_rejected_media(home, o_media[i], session, 0);
}
}
for (j = 0; j < Nu; j++) {
if (u_media[j] == SDP_MEDIA_NONE)
continue;
for (i = 0; i < Nmax; i++) {
if (s_media[i] == NULL) {
s_media[i] = u_media[j], u_media[j] = SDP_MEDIA_NONE;
u2s[j] = i, s2u[i] = j;
break;
}
}
assert(i != Nmax);
}
}
/* Match unused user media by media types with the existing session */
for (i = 0; i < Ns; i++) {
if (s_media[i])
continue;
j = soa_sdp_matching_mindex(ss, u_media, o_media[i], NULL);
if (j == -1) {
s_media[i] = soa_sdp_make_rejected_media(home, o_media[i], session, 0);
continue;
}
s_media[i] = u_media[j], u_media[j] = SDP_MEDIA_NONE;
u2s[j] = i, s2u[i] = j;
}
/* Here we just append new media at the end */
for (j = 0; j < Nu; j++) {
if (u_media[j] != SDP_MEDIA_NONE) {
s_media[i] = u_media[j], u_media[j] = SDP_MEDIA_NONE;
u2s[j] = i, s2u[i] = j;
i++;
}
}
assert(i <= Nmax);
}
mm = &session->sdp_media;
for (i = 0; s_media[i]; i++) {
m = s_media[i]; *mm = m; mm = &m->m_next;
}
*mm = NULL;
s2u[n = i] = U2S_SENTINEL;
*return_u2s = u2s;
*return_s2u = s2u;
#ifndef NDEBUG /* X check */
for (j = 0; j < Nu; j++) {
i = u2s[j];
assert(i == U2S_NOT_USED || s2u[i] == j);
}
for (i = 0; i < n; i++) {
j = s2u[i];
assert(j == U2S_NOT_USED || u2s[j] == i);
}
#endif
return 0;
}
/**
* Updates the modified copy of local SDP based
* on application provided local SDP and remote SDP.
*/
static int offer_answer_step(soa_session_t *ss,
enum offer_answer_action action,
char const *by)
{
soa_static_session_t *sss = (soa_static_session_t *)ss;
sdp_session_t *local = ss->ss_local->ssd_sdp;
sdp_session_t local0[1];
sdp_session_t *user = ss->ss_user->ssd_sdp;
unsigned user_version = ss->ss_user_version;
sdp_session_t *remote = ss->ss_remote->ssd_sdp;
unsigned remote_version = ss->ss_remote_version;
int fresh = 0;
sdp_origin_t o[1] = {{ sizeof(o) }};
sdp_connection_t *c, c0[1] = {{ sizeof(c0) }};
char c0_buffer[64];
sdp_time_t t[1] = {{ sizeof(t) }};
int *u2s = NULL, *s2u = NULL, *tbf;
sdp_session_t *latest = NULL, *previous = NULL;
char const *phrase = "Internal Media Error";
su_home_t tmphome[SU_HOME_AUTO_SIZE(8192)];
su_home_auto(tmphome, sizeof tmphome);
SU_DEBUG_7(("soa_static_offer_answer_action(%p, %s): called\n",
(void *)ss, by));
if (user == NULL)
return soa_set_status(ss, 500, "No session set by user");
if (action == generate_offer)
remote = NULL;
else if (remote == NULL)
return soa_set_status(ss, 500, "No remote SDP");
/* Pre-negotiation Step: Expand truncated remote SDP */
if (local && remote) switch (action) {
case generate_answer:
case process_answer:
if (sdp_media_count(remote, sdp_media_any, "*", (sdp_proto_e)0, (sdp_text_t)0) <
sdp_media_count(local, sdp_media_any, "*", (sdp_proto_e)0, (sdp_text_t)0)) {
SU_DEBUG_5(("%s: remote %s is truncated: expanding\n",
by, action == generate_answer ? "offer" : "answer"));
remote = soa_sdp_expand_media(tmphome, remote, local);
if (remote == NULL)
return soa_set_status(ss, 500, "Cannot expand remote session");
}
default:
break;
}
/* Step A: Create local SDP session (based on user-supplied SDP) */
if (local == NULL) switch (action) {
case generate_offer:
case generate_answer:
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"generating local description"));
fresh = 1;
local = local0;
*local = *user, local->sdp_media = NULL;
o->o_username = "******";
o->o_address = c0;
c0->c_address = c0_buffer;
if (!local->sdp_origin)
local->sdp_origin = o;
break;
case process_answer:
default:
goto internal_error;
}
/* Step B: upgrade local SDP (add m= lines to it) */
switch (action) {
case generate_offer:
/* Upgrade local SDP based on user SDP */
if (local != local0 && ss->ss_local_user_version == user_version)
break;
if (local != local0)
*local0 = *local, local = local0;
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"upgrade with local description"));
if (soa_sdp_upgrade(ss, tmphome, local, user, NULL, &u2s, &s2u) < 0)
goto internal_error;
break;
case generate_answer:
/* Upgrade local SDP based on remote SDP */
if (ss->ss_local_user_version == user_version &&
ss->ss_local_remote_version == remote_version)
break;
if (1) {
if (local != local0)
*local0 = *local, local = local0;
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"upgrade with remote description"));
if (soa_sdp_upgrade(ss, tmphome, local, user, remote, &u2s, &s2u) < 0)
goto internal_error;
}
break;
case process_answer:
default:
break;
}
/* Step C: reject media */
switch (action) {
case generate_offer:
/* Local media is marked as rejected already in upgrade phase */
break;
case generate_answer:
case process_answer:
if (ss->ss_local_remote_version == remote_version)
break;
if (soa_sdp_reject_is_needed(local, remote)) {
if (local != local0) {
*local0 = *local, local = local0;
#define DUP_LOCAL(local) \
do { \
if (!local->sdp_media) break; \
local->sdp_media = \
sdp_media_dup_all(tmphome, local->sdp_media, local); \
if (!local->sdp_media) \
goto internal_error; \
} while (0)
DUP_LOCAL(local);
}
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"marking rejected media"));
soa_sdp_reject(tmphome, local, remote);
}
break;
default:
break;
}
/* Step D: Set media mode bits */
switch (action) {
int const *s2u_;
case generate_offer:
case generate_answer:
case process_answer:
s2u_ = s2u;
if (!s2u_) s2u_ = sss->sss_s2u;
if (soa_sdp_mode_set(user, s2u_, local, remote, ss->ss_hold, 1)) {
if (local != local0) {
*local0 = *local, local = local0;
DUP_LOCAL(local);
}
soa_sdp_mode_set(user, s2u_, local, remote, ss->ss_hold, 0);
}
break;
default:
break;
}
/* Step E: Upgrade codecs by answer. */
switch (action) {
case process_answer:
/* Upgrade local SDP based on remote SDP */
if (ss->ss_local_remote_version == remote_version)
break;
if (1 /* We don't have good test for codecs */) {
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"upgrade codecs with remote description"));
if (local != local0) {
*local0 = *local, local = local0;
DUP_LOCAL(local);
}
soa_sdp_session_upgrade_rtpmaps(ss, local, remote);
}
break;
case generate_offer:
case generate_answer:
default:
break;
}
/* Step F0: Initialize o= line */
if (fresh) {
if (user->sdp_origin) {
o->o_username = user->sdp_origin->o_username;
if (user->sdp_origin->o_address)
o->o_address = user->sdp_origin->o_address;
if (user->sdp_origin->o_id)
o->o_id = user->sdp_origin->o_id;
if (user->sdp_origin->o_version && user->sdp_origin->o_version != o->o_version) {
o->o_version = user->sdp_origin->o_version;
o->o_version--;
}
}
if (soa_init_sdp_origin_with_session(ss, o, c0_buffer, local) < 0) {
phrase = "Cannot Get IP Address for Session Description";
goto internal_error;
}
local->sdp_origin = o;
}
/* Step F: Update c= line(s) */
switch (action) {
sdp_connection_t *user_c, *local_c;
case generate_offer:
case generate_answer:
user_c = user->sdp_connection;
if (!soa_check_sdp_connection(user_c))
user_c = NULL;
local_c = local->sdp_connection;
if (!soa_check_sdp_connection(local_c))
local_c = NULL;
if (ss->ss_local_user_version != user_version ||
local_c == NULL ||
(user_c != NULL && sdp_connection_cmp(local_c, user_c))) {
sdp_media_t *m;
if (user_c)
c = user_c;
else
c = local->sdp_origin->o_address;
/* Every m= line (even rejected one) must have a c= line
* or there must be a c= line at session level
*/
for (m = local->sdp_media; m; m = m->m_next)
if (m->m_connections == NULL)
break;
if (m) {
if (local != local0) {
*local0 = *local, local = local0;
DUP_LOCAL(local);
}
local->sdp_connection = c;
}
}
break;
default:
break;
}
soa_description_free(ss, ss->ss_previous);
su_free(ss->ss_home, sss->sss_previous.u2s), sss->sss_previous.u2s = NULL;
su_free(ss->ss_home, sss->sss_previous.s2u), sss->sss_previous.s2u = NULL;
if (u2s) {
u2s = u2s_alloc(ss->ss_home, u2s);
s2u = u2s_alloc(ss->ss_home, s2u);
if (!u2s || !s2u)
goto internal_error;
}
if (ss->ss_local->ssd_sdp != local &&
sdp_session_cmp(ss->ss_local->ssd_sdp, local)) {
int bump;
switch (action) {
case generate_offer:
bump = sdp_session_cmp(local, sss->sss_latest);
break;
case generate_answer:
bump = 1;
break;
case process_answer:
default:
bump = 0;
break;
}
if (bump) {
/* Upgrade the version number */
if (local->sdp_origin != o)
*o = *local->sdp_origin, local->sdp_origin = o;
o->o_version++;
}
/* Do sanity checks for the created SDP */
if (!local->sdp_subject) /* s= is mandatory */
local->sdp_subject = "-";
if (!local->sdp_time) /* t= is mandatory */
local->sdp_time = t;
if (action == generate_offer) {
/* Keep a copy of previous session state */
int *previous_u2s = u2s_alloc(ss->ss_home, sss->sss_u2s);
int *previous_s2u = u2s_alloc(ss->ss_home, sss->sss_s2u);
if ((sss->sss_u2s && !previous_u2s) || (sss->sss_s2u && !previous_s2u))
goto internal_error;
*ss->ss_previous = *ss->ss_local;
memset(ss->ss_local, 0, (sizeof *ss->ss_local));
ss->ss_previous_user_version = ss->ss_local_user_version;
ss->ss_previous_remote_version = ss->ss_local_remote_version;
sss->sss_previous.u2s = previous_u2s;
sss->sss_previous.s2u = previous_s2u;
}
SU_DEBUG_7(("soa_static(%p, %s): %s\n", (void *)ss, by,
"storing local description"));
/* Update the unparsed and pretty-printed descriptions */
if (soa_description_set(ss, ss->ss_local, local, NULL, 0) < 0) {
if (action == generate_offer) {
/* Remove 2nd reference to local session state */
memset(ss->ss_previous, 0, (sizeof *ss->ss_previous));
ss->ss_previous_user_version = 0;
ss->ss_previous_remote_version = 0;
su_free(ss->ss_home, sss->sss_previous.u2s), sss->sss_previous.u2s = NULL;
su_free(ss->ss_home, sss->sss_previous.s2u), sss->sss_previous.s2u = NULL;
}
su_free(ss->ss_home, u2s), su_free(ss->ss_home, s2u);
goto internal_error;
}
if (bump) {
latest = sdp_session_dup(ss->ss_home, ss->ss_local->ssd_sdp);
previous = sss->sss_latest;
}
}
if (u2s) {
tbf = sss->sss_u2s, sss->sss_u2s = u2s, su_free(ss->ss_home, tbf);
tbf = sss->sss_s2u, sss->sss_s2u = s2u, su_free(ss->ss_home, tbf);
}
/* Update version numbers */
switch (action) {
case generate_offer:
ss->ss_local_user_version = user_version;
sss->sss_latest = latest;
break;
case generate_answer:
ss->ss_local_user_version = user_version;
ss->ss_local_remote_version = remote_version;
sss->sss_latest = latest;
break;
case process_answer:
ss->ss_local_remote_version = remote_version;
default:
break;
}
if (previous)
su_free(ss->ss_home, previous);
su_home_deinit(tmphome);
return 0;
internal_error:
su_home_deinit(tmphome);
return soa_set_status(ss, 500, phrase);
}
