janus_dtls_srtp *janus_dtls_srtp_create(void *ice_component, janus_dtls_role role) {
janus_ice_component *component = (janus_ice_component *)ice_component;
if(component == NULL) {
JANUS_LOG(LOG_ERR, "No component, no DTLS...\n");
return NULL;
}
janus_ice_stream *stream = component->stream;
if(!stream) {
JANUS_LOG(LOG_ERR, "No stream, no DTLS...\n");
return NULL;
}
janus_ice_handle *handle = stream->handle;
if(!handle || !handle->agent) {
JANUS_LOG(LOG_ERR, "No handle/agent, no DTLS...\n");
return NULL;
}
janus_dtls_srtp *dtls = calloc(1, sizeof(janus_dtls_srtp));
if(dtls == NULL) {
JANUS_LOG(LOG_FATAL, "Memory error!\n");
return NULL;
}
/* Create SSL context, at last */
dtls->srtp_valid = 0;
dtls->dtls_last_msg = NULL;
dtls->dtls_last_len = 0;
dtls->ssl = SSL_new(janus_dtls_get_ssl_ctx());
if(!dtls->ssl) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] No component DTLS SSL session??\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
SSL_set_ex_data(dtls->ssl, 0, dtls);
SSL_set_info_callback(dtls->ssl, janus_dtls_callback);
dtls->read_bio = BIO_new(BIO_s_mem());
if(!dtls->read_bio) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating read BIO!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
BIO_set_mem_eof_return(dtls->read_bio, -1);
dtls->write_bio = BIO_new(BIO_s_mem());
if(!dtls->write_bio) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating write BIO!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
BIO_set_mem_eof_return(dtls->write_bio, -1);
SSL_set_bio(dtls->ssl, dtls->read_bio, dtls->write_bio);
dtls->dtls_role = role;
if(dtls->dtls_role == JANUS_DTLS_ROLE_CLIENT) {
JANUS_LOG(LOG_VERB, "[%"SCNu64"] Setting connect state (DTLS client)\n", handle->handle_id);
SSL_set_connect_state(dtls->ssl);
} else {
JANUS_LOG(LOG_VERB, "[%"SCNu64"] Setting accept state (DTLS server)\n", handle->handle_id);
SSL_set_accept_state(dtls->ssl);
}
/* Done */
dtls->component = component;
return dtls;
}
janus_dtls_srtp *janus_dtls_srtp_create(void *ice_component, janus_dtls_role role) {
janus_ice_component *component = (janus_ice_component *)ice_component;
if(component == NULL) {
JANUS_LOG(LOG_ERR, "No component, no DTLS...\n");
return NULL;
}
janus_ice_stream *stream = component->stream;
if(!stream) {
JANUS_LOG(LOG_ERR, "No stream, no DTLS...\n");
return NULL;
}
janus_ice_handle *handle = stream->handle;
if(!handle || !handle->agent) {
JANUS_LOG(LOG_ERR, "No handle/agent, no DTLS...\n");
return NULL;
}
janus_dtls_srtp *dtls = g_malloc0(sizeof(janus_dtls_srtp));
if(dtls == NULL) {
JANUS_LOG(LOG_FATAL, "Memory error!\n");
return NULL;
}
/* Create SSL context, at last */
dtls->srtp_valid = 0;
dtls->ssl = SSL_new(janus_dtls_get_ssl_ctx());
if(!dtls->ssl) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] No component DTLS SSL session??\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
SSL_set_ex_data(dtls->ssl, 0, dtls);
SSL_set_info_callback(dtls->ssl, janus_dtls_callback);
dtls->read_bio = BIO_new(BIO_s_mem());
if(!dtls->read_bio) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating read BIO!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
BIO_set_mem_eof_return(dtls->read_bio, -1);
dtls->write_bio = BIO_new(BIO_s_mem());
if(!dtls->write_bio) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating write BIO!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
BIO_set_mem_eof_return(dtls->write_bio, -1);
/* The write BIO needs our custom filter, or fragmentation won't work */
dtls->filter_bio = BIO_new(BIO_janus_dtls_filter());
if(!dtls->filter_bio) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating filter BIO!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
/* Chain filter and write BIOs */
BIO_push(dtls->filter_bio, dtls->write_bio);
/* Set the filter as the BIO to use for outgoing data */
SSL_set_bio(dtls->ssl, dtls->read_bio, dtls->filter_bio);
dtls->dtls_role = role;
if(dtls->dtls_role == JANUS_DTLS_ROLE_CLIENT) {
JANUS_LOG(LOG_VERB, "[%"SCNu64"] Setting connect state (DTLS client)\n", handle->handle_id);
SSL_set_connect_state(dtls->ssl);
} else {
JANUS_LOG(LOG_VERB, "[%"SCNu64"] Setting accept state (DTLS server)\n", handle->handle_id);
SSL_set_accept_state(dtls->ssl);
}
/* https://code.google.com/p/chromium/issues/detail?id=406458
* Specify an ECDH group for ECDHE ciphers, otherwise they cannot be
* negotiated when acting as the server. Use NIST's P-256 which is
* commonly supported.
*/
EC_KEY* ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
if(ecdh == NULL) {
JANUS_LOG(LOG_ERR, "[%"SCNu64"] Error creating ECDH group!\n", handle->handle_id);
janus_dtls_srtp_destroy(dtls);
return NULL;
}
SSL_set_options(dtls->ssl, SSL_OP_SINGLE_ECDH_USE);
SSL_set_tmp_ecdh(dtls->ssl, ecdh);
EC_KEY_free(ecdh);
dtls->ready = 0;
#ifdef HAVE_SCTP
dtls->sctp = NULL;
#endif
janus_mutex_init(&dtls->srtp_mutex);
/* Done */
dtls->dtls_connected = 0;
dtls->component = component;
return dtls;
}