/* Generate crypto attribute, including crypto key.
* If crypto-suite chosen is crypto NULL, just return PJ_SUCCESS,
* and set buffer_len = 0.
*/
static pj_status_t generate_crypto_attr_value(pj_pool_t *pool,
char *buffer, int *buffer_len,
pjmedia_srtp_crypto *crypto,
int tag)
{
pj_status_t status;
int cs_idx = get_crypto_idx(&crypto->name);
char b64_key[PJ_BASE256_TO_BASE64_LEN(MAX_KEY_LEN)+1];
int b64_key_len = sizeof(b64_key);
if (cs_idx == -1)
return PJMEDIA_SRTP_ENOTSUPCRYPTO;
/* Crypto-suite NULL. */
if (cs_idx == 0) {
*buffer_len = 0;
return PJ_SUCCESS;
}
/* Generate key if not specified. */
if (crypto->key.slen == 0) {
pj_bool_t key_ok;
char key[MAX_KEY_LEN];
err_status_t err;
unsigned i;
PJ_ASSERT_RETURN(MAX_KEY_LEN >= crypto_suites[cs_idx].cipher_key_len,
PJ_ETOOSMALL);
do {
key_ok = PJ_TRUE;
err = crypto_get_random((unsigned char*)key,
crypto_suites[cs_idx].cipher_key_len);
if (err != err_status_ok) {
PJ_LOG(5,(THIS_FILE, "Failed generating random key: %s",
get_libsrtp_errstr(err)));
return PJMEDIA_ERRNO_FROM_LIBSRTP(err);
}
for (i=0; i<crypto_suites[cs_idx].cipher_key_len && key_ok; ++i)
if (key[i] == 0) key_ok = PJ_FALSE;
} while (!key_ok);
crypto->key.ptr = (char*)
pj_pool_zalloc(pool,
crypto_suites[cs_idx].cipher_key_len);
pj_memcpy(crypto->key.ptr, key, crypto_suites[cs_idx].cipher_key_len);
crypto->key.slen = crypto_suites[cs_idx].cipher_key_len;
}
if (crypto->key.slen != (pj_ssize_t)crypto_suites[cs_idx].cipher_key_len)
return PJMEDIA_SRTP_EINKEYLEN;
/* Key transmitted via SDP should be base64 encoded. */
status = pj_base64_encode((pj_uint8_t*)crypto->key.ptr, crypto->key.slen,
b64_key, &b64_key_len);
if (status != PJ_SUCCESS) {
PJ_LOG(5,(THIS_FILE, "Failed encoding plain key to base64"));
return status;
}
b64_key[b64_key_len] = '\0';
PJ_ASSERT_RETURN(*buffer_len >= (crypto->name.slen + \
b64_key_len + 16), PJ_ETOOSMALL);
/* Print the crypto attribute value. */
*buffer_len = pj_ansi_snprintf(buffer, *buffer_len, "%d %s inline:%s",
tag,
crypto_suites[cs_idx].name,
b64_key);
return PJ_SUCCESS;
}
/*
* Initialize and start SRTP session with the given parameters.
*/
PJ_DEF(pj_status_t) pjmedia_transport_srtp_start(
pjmedia_transport *tp,
const pjmedia_srtp_crypto *tx,
const pjmedia_srtp_crypto *rx)
{
transport_srtp *srtp = (transport_srtp*) tp;
srtp_policy_t tx_;
srtp_policy_t rx_;
err_status_t err;
int cr_tx_idx = 0;
int au_tx_idx = 0;
int cr_rx_idx = 0;
int au_rx_idx = 0;
int crypto_suites_cnt;
PJ_ASSERT_RETURN(tp && tx && rx, PJ_EINVAL);
if (srtp->session_inited) {
pjmedia_transport_srtp_stop(tp);
}
crypto_suites_cnt = sizeof(crypto_suites)/sizeof(crypto_suites[0]);
/* Get encryption and authentication method */
cr_tx_idx = au_tx_idx = get_crypto_idx(&tx->name);
if (tx->flags & PJMEDIA_SRTP_NO_ENCRYPTION)
cr_tx_idx = 0;
if (tx->flags & PJMEDIA_SRTP_NO_AUTHENTICATION)
au_tx_idx = 0;
cr_rx_idx = au_rx_idx = get_crypto_idx(&rx->name);
if (rx->flags & PJMEDIA_SRTP_NO_ENCRYPTION)
cr_rx_idx = 0;
if (rx->flags & PJMEDIA_SRTP_NO_AUTHENTICATION)
au_rx_idx = 0;
/* Check whether the crypto-suite requested is supported */
if (cr_tx_idx == -1 || cr_rx_idx == -1 || au_tx_idx == -1 ||
au_rx_idx == -1)
return PJMEDIA_SRTP_ENOTSUPCRYPTO;
/* If all options points to 'NULL' method, just bypass SRTP */
if (cr_tx_idx == 0 && cr_rx_idx == 0 && au_tx_idx == 0 && au_rx_idx == 0) {
srtp->bypass_srtp = PJ_TRUE;
return PJ_SUCCESS;
}
/* Check key length */
if (tx->key.slen != (pj_ssize_t)crypto_suites[cr_tx_idx].cipher_key_len ||
rx->key.slen != (pj_ssize_t)crypto_suites[cr_rx_idx].cipher_key_len)
return PJMEDIA_SRTP_EINKEYLEN;
/* Init transmit direction */
pj_bzero(&tx_, sizeof(srtp_policy_t));
pj_memmove(srtp->tx_key, tx->key.ptr, tx->key.slen);
if (cr_tx_idx && au_tx_idx)
tx_.rtp.sec_serv = sec_serv_conf_and_auth;
else if (cr_tx_idx)
tx_.rtp.sec_serv = sec_serv_conf;
else if (au_tx_idx)
tx_.rtp.sec_serv = sec_serv_auth;
else
tx_.rtp.sec_serv = sec_serv_none;
tx_.key = (uint8_t*)srtp->tx_key;
tx_.ssrc.type = ssrc_any_outbound;
tx_.ssrc.value = 0;
tx_.rtp.cipher_type = crypto_suites[cr_tx_idx].cipher_type;
tx_.rtp.cipher_key_len = crypto_suites[cr_tx_idx].cipher_key_len;
tx_.rtp.auth_type = crypto_suites[au_tx_idx].auth_type;
tx_.rtp.auth_key_len = crypto_suites[au_tx_idx].auth_key_len;
tx_.rtp.auth_tag_len = crypto_suites[au_tx_idx].srtp_auth_tag_len;
tx_.rtcp = tx_.rtp;
tx_.rtcp.auth_tag_len = crypto_suites[au_tx_idx].srtcp_auth_tag_len;
tx_.next = NULL;
err = srtp_create(&srtp->srtp_tx_ctx, &tx_);
if (err != err_status_ok) {
return PJMEDIA_ERRNO_FROM_LIBSRTP(err);
}
srtp->tx_policy = *tx;
pj_strset(&srtp->tx_policy.key, srtp->tx_key, tx->key.slen);
srtp->tx_policy.name=pj_str(crypto_suites[get_crypto_idx(&tx->name)].name);
/* Init receive direction */
pj_bzero(&rx_, sizeof(srtp_policy_t));
pj_memmove(srtp->rx_key, rx->key.ptr, rx->key.slen);
if (cr_rx_idx && au_rx_idx)
rx_.rtp.sec_serv = sec_serv_conf_and_auth;
else if (cr_rx_idx)
rx_.rtp.sec_serv = sec_serv_conf;
else if (au_rx_idx)
rx_.rtp.sec_serv = sec_serv_auth;
else
rx_.rtp.sec_serv = sec_serv_none;
rx_.key = (uint8_t*)srtp->rx_key;
rx_.ssrc.type = ssrc_any_inbound;
rx_.ssrc.value = 0;
rx_.rtp.sec_serv = crypto_suites[cr_rx_idx].service;
rx_.rtp.cipher_type = crypto_suites[cr_rx_idx].cipher_type;
rx_.rtp.cipher_key_len = crypto_suites[cr_rx_idx].cipher_key_len;
rx_.rtp.auth_type = crypto_suites[au_rx_idx].auth_type;
rx_.rtp.auth_key_len = crypto_suites[au_rx_idx].auth_key_len;
rx_.rtp.auth_tag_len = crypto_suites[au_rx_idx].srtp_auth_tag_len;
rx_.rtcp = rx_.rtp;
rx_.rtcp.auth_tag_len = crypto_suites[au_rx_idx].srtcp_auth_tag_len;
rx_.next = NULL;
err = srtp_create(&srtp->srtp_rx_ctx, &rx_);
if (err != err_status_ok) {
srtp_dealloc(srtp->srtp_tx_ctx);
return PJMEDIA_ERRNO_FROM_LIBSRTP(err);
}
srtp->rx_policy = *rx;
pj_strset(&srtp->rx_policy.key, srtp->rx_key, rx->key.slen);
srtp->rx_policy.name=pj_str(crypto_suites[get_crypto_idx(&rx->name)].name);
/* Declare SRTP session initialized */
srtp->session_inited = PJ_TRUE;
PJ_LOG(5, (srtp->pool->obj_name, "TX: %s key=%s", srtp->tx_policy.name.ptr,
octet_string_hex_string(tx->key.ptr, tx->key.slen)));
if (srtp->tx_policy.flags) {
PJ_LOG(5,(srtp->pool->obj_name,"TX: disable%s%s", (cr_tx_idx?"":" enc"),
(au_tx_idx?"":" auth")));
}
PJ_LOG(5, (srtp->pool->obj_name, "RX: %s key=%s", srtp->rx_policy.name.ptr,
octet_string_hex_string(rx->key.ptr, rx->key.slen)));
if (srtp->rx_policy.flags) {
PJ_LOG(5,(srtp->pool->obj_name,"RX: disable%s%s", (cr_rx_idx?"":" enc"),
(au_rx_idx?"":" auth")));
}
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 *sdp_remote,
unsigned media_index)
{
struct transport_srtp *srtp = (struct transport_srtp*) tp;
pjmedia_sdp_media *m_rem, *m_loc;
enum { MAXLEN = 512 };
char buffer[MAXLEN];
int buffer_len;
pj_status_t status;
pjmedia_sdp_attr *attr;
pj_str_t attr_value;
unsigned i, j;
PJ_ASSERT_RETURN(tp && sdp_pool && sdp_local, PJ_EINVAL);
srtp->offerer_side = sdp_remote == NULL;
m_rem = sdp_remote ? sdp_remote->media[media_index] : NULL;
m_loc = sdp_local->media[media_index];
/* Bypass if media transport is not RTP/AVP or RTP/SAVP */
if (pj_stricmp(&m_loc->desc.transport, &ID_RTP_AVP) != 0 &&
pj_stricmp(&m_loc->desc.transport, &ID_RTP_SAVP) != 0)
goto BYPASS_SRTP;
/* If the media is inactive, do nothing. */
if (pjmedia_sdp_media_find_attr(m_loc, &ID_INACTIVE, NULL) ||
(m_rem && pjmedia_sdp_media_find_attr(m_rem, &ID_INACTIVE, NULL)))
goto BYPASS_SRTP;
/* Check remote media transport & set local media transport
* based on SRTP usage option.
*/
if (srtp->offerer_side) {
/* Generate transport */
switch (srtp->setting.use) {
case PJMEDIA_SRTP_DISABLED:
goto BYPASS_SRTP;
case PJMEDIA_SRTP_OPTIONAL:
m_loc->desc.transport =
(srtp->peer_use == PJMEDIA_SRTP_MANDATORY)?
ID_RTP_SAVP : ID_RTP_AVP;
break;
case PJMEDIA_SRTP_MANDATORY:
m_loc->desc.transport = ID_RTP_SAVP;
break;
}
/* Generate crypto attribute if not yet */
if (pjmedia_sdp_media_find_attr(m_loc, &ID_CRYPTO, NULL) == NULL) {
for (i=0; i<srtp->setting.crypto_count; ++i) {
/* Offer crypto-suites based on setting. */
buffer_len = MAXLEN;
status = generate_crypto_attr_value(srtp->pool, buffer, &buffer_len,
&srtp->setting.crypto[i],
i+1);
if (status != PJ_SUCCESS)
return status;
/* If buffer_len==0, just skip the crypto attribute. */
if (buffer_len) {
pj_strset(&attr_value, buffer, buffer_len);
attr = pjmedia_sdp_attr_create(srtp->pool, ID_CRYPTO.ptr,
&attr_value);
m_loc->attr[m_loc->attr_count++] = attr;
}
}
}
} else {
/* Answerer side */
pj_assert(sdp_remote && m_rem);
/* Generate transport */
switch (srtp->setting.use) {
case PJMEDIA_SRTP_DISABLED:
if (pj_stricmp(&m_rem->desc.transport, &ID_RTP_SAVP) == 0)
return PJMEDIA_SRTP_ESDPINTRANSPORT;
goto BYPASS_SRTP;
case PJMEDIA_SRTP_OPTIONAL:
m_loc->desc.transport = m_rem->desc.transport;
break;
case PJMEDIA_SRTP_MANDATORY:
if (pj_stricmp(&m_rem->desc.transport, &ID_RTP_SAVP) != 0)
return PJMEDIA_SRTP_ESDPINTRANSPORT;
m_loc->desc.transport = ID_RTP_SAVP;
break;
}
/* Generate crypto attribute if not yet */
if (pjmedia_sdp_media_find_attr(m_loc, &ID_CRYPTO, NULL) == NULL) {
pjmedia_srtp_crypto tmp_rx_crypto;
pj_bool_t has_crypto_attr = PJ_FALSE;
int matched_idx = -1;
int chosen_tag = 0;
int tags[64]; /* assume no more than 64 crypto attrs in a media */
unsigned cr_attr_count = 0;
/* Find supported crypto-suite, get the tag, and assign policy_local */
for (i=0; i<m_rem->attr_count; ++i) {
if (pj_stricmp(&m_rem->attr[i]->name, &ID_CRYPTO) != 0)
continue;
has_crypto_attr = PJ_TRUE;
status = parse_attr_crypto(srtp->pool, m_rem->attr[i],
&tmp_rx_crypto, &tags[cr_attr_count]);
if (status != PJ_SUCCESS)
return status;
/* Check duplicated tag */
for (j=0; j<cr_attr_count; ++j) {
if (tags[j] == tags[cr_attr_count]) {
DEACTIVATE_MEDIA(sdp_pool, m_loc);
return PJMEDIA_SRTP_ESDPDUPCRYPTOTAG;
}
}
if (matched_idx == -1) {
/* lets see if the crypto-suite offered is supported */
for (j=0; j<srtp->setting.crypto_count; ++j)
if (pj_stricmp(&tmp_rx_crypto.name,
&srtp->setting.crypto[j].name) == 0)
{
int cs_idx = get_crypto_idx(&tmp_rx_crypto.name);
/* Force to use test key */
/* bad keys for snom: */
//char *hex_test_key = "58b29c5c8f42308120ce857e439f2d"
// "7810a8b10ad0b1446be5470faea496";
//char *hex_test_key = "20a26aac7ba062d356ff52b61e3993"
// "ccb78078f12c64db94b9c294927fd0";
//pj_str_t *test_key = &srtp->setting.crypto[j].key;
//char *raw_test_key = pj_pool_zalloc(srtp->pool, 64);
//hex_string_to_octet_string(
// raw_test_key,
// hex_test_key,
// strlen(hex_test_key));
//pj_strset(test_key, raw_test_key,
// crypto_suites[cs_idx].cipher_key_len);
/* EO Force to use test key */
if (tmp_rx_crypto.key.slen !=
(int)crypto_suites[cs_idx].cipher_key_len)
return PJMEDIA_SRTP_EINKEYLEN;
srtp->rx_policy_neg = tmp_rx_crypto;
chosen_tag = tags[cr_attr_count];
matched_idx = j;
break;
}
}
cr_attr_count++;
}
/* Check crypto negotiation result */
switch (srtp->setting.use) {
case PJMEDIA_SRTP_DISABLED:
pj_assert(!"Should never reach here");
break;
case PJMEDIA_SRTP_OPTIONAL:
/* bypass SRTP when no crypto-attr and remote uses RTP/AVP */
if (!has_crypto_attr &&
pj_stricmp(&m_rem->desc.transport, &ID_RTP_AVP) == 0)
goto BYPASS_SRTP;
/* bypass SRTP when nothing match and remote uses RTP/AVP */
else if (matched_idx == -1 &&
pj_stricmp(&m_rem->desc.transport, &ID_RTP_AVP) == 0)
goto BYPASS_SRTP;
break;
case PJMEDIA_SRTP_MANDATORY:
/* Do nothing, intentional */
break;
}
/* No crypto attr */
if (!has_crypto_attr) {
DEACTIVATE_MEDIA(sdp_pool, m_loc);
return PJMEDIA_SRTP_ESDPREQCRYPTO;
}
/* No crypto match */
if (matched_idx == -1) {
DEACTIVATE_MEDIA(sdp_pool, m_loc);
return PJMEDIA_SRTP_ENOTSUPCRYPTO;
}
/* we have to generate crypto answer,
* with srtp->tx_policy_neg matched the offer
* and rem_tag contains matched offer tag.
*/
buffer_len = MAXLEN;
status = generate_crypto_attr_value(srtp->pool, buffer, &buffer_len,
&srtp->setting.crypto[matched_idx],
chosen_tag);
if (status != PJ_SUCCESS)
return status;
srtp->tx_policy_neg = srtp->setting.crypto[matched_idx];
/* If buffer_len==0, just skip the crypto attribute. */
if (buffer_len) {
pj_strset(&attr_value, buffer, buffer_len);
attr = pjmedia_sdp_attr_create(sdp_pool, ID_CRYPTO.ptr,
&attr_value);
m_loc->attr[m_loc->attr_count++] = attr;
}
/* At this point, we get valid rx_policy_neg & tx_policy_neg. */
}
}
goto PROPAGATE_MEDIA_CREATE;
BYPASS_SRTP:
srtp->bypass_srtp = PJ_TRUE;
PROPAGATE_MEDIA_CREATE:
return pjmedia_transport_encode_sdp(srtp->member_tp, sdp_pool,
sdp_local, sdp_remote, media_index);
}
/*
* Create an SRTP media transport.
*/
PJ_DEF(pj_status_t) pjmedia_transport_srtp_create(
pjmedia_endpt *endpt,
pjmedia_transport *tp,
const pjmedia_srtp_setting *opt,
pjmedia_transport **p_tp)
{
pj_pool_t *pool;
transport_srtp *srtp;
pj_status_t status;
unsigned i;
PJ_ASSERT_RETURN(endpt && tp && p_tp, PJ_EINVAL);
/* Check crypto availability */
if (opt && opt->crypto_count == 0 &&
opt->use == PJMEDIA_SRTP_MANDATORY)
return PJMEDIA_SRTP_ESDPREQCRYPTO;
/* Check crypto */
if (opt && opt->use != PJMEDIA_SRTP_DISABLED) {
for (i=0; i < opt->crypto_count; ++i) {
int cs_idx = get_crypto_idx(&opt->crypto[i].name);
/* check crypto name */
if (cs_idx == -1)
return PJMEDIA_SRTP_ENOTSUPCRYPTO;
/* check key length */
if (opt->crypto[i].key.slen &&
opt->crypto[i].key.slen <
(pj_ssize_t)crypto_suites[cs_idx].cipher_key_len)
return PJMEDIA_SRTP_EINKEYLEN;
}
}
/* Init libsrtp. */
status = pjmedia_srtp_init_lib();
if (status != PJ_SUCCESS)
return status;
pool = pjmedia_endpt_create_pool(endpt, "srtp%p", 1000, 1000);
srtp = PJ_POOL_ZALLOC_T(pool, transport_srtp);
srtp->pool = pool;
srtp->session_inited = PJ_FALSE;
srtp->bypass_srtp = PJ_FALSE;
srtp->probation_cnt = PROBATION_CNT_INIT;
if (opt) {
srtp->setting = *opt;
if (opt->use == PJMEDIA_SRTP_DISABLED)
srtp->setting.crypto_count = 0;
for (i=0; i < srtp->setting.crypto_count; ++i) {
int cs_idx = get_crypto_idx(&opt->crypto[i].name);
pj_str_t tmp_key = opt->crypto[i].key;
/* re-set crypto */
srtp->setting.crypto[i].name = pj_str(crypto_suites[cs_idx].name);
/* cut key length */
if (tmp_key.slen)
tmp_key.slen = crypto_suites[cs_idx].cipher_key_len;
pj_strdup(pool, &srtp->setting.crypto[i].key, &tmp_key);
}
} else {
pjmedia_srtp_setting_default(&srtp->setting);
}
status = pj_lock_create_recursive_mutex(pool, pool->obj_name, &srtp->mutex);
if (status != PJ_SUCCESS) {
pj_pool_release(pool);
return status;
}
/* Initialize base pjmedia_transport */
pj_memcpy(srtp->base.name, pool->obj_name, PJ_MAX_OBJ_NAME);
if (tp)
srtp->base.type = tp->type;
else
srtp->base.type = PJMEDIA_TRANSPORT_TYPE_UDP;
srtp->base.op = &transport_srtp_op;
/* Set underlying transport */
srtp->member_tp = tp;
/* Initialize peer's SRTP usage mode. */
srtp->peer_use = srtp->setting.use;
/* Done */
*p_tp = &srtp->base;
return PJ_SUCCESS;
}
/*
* Initialize and start SRTP session with the given parameters.
*/
PJ_DEF(pj_status_t) pjmedia_transport_srtp_start(
pjmedia_transport *tp,
const pjmedia_srtp_crypto *tx,
const pjmedia_srtp_crypto *rx)
{
transport_srtp *srtp = (transport_srtp*) tp;
srtp_policy_t tx_;
srtp_policy_t rx_;
err_status_t err;
int cr_tx_idx = 0;
int au_tx_idx = 0;
int cr_rx_idx = 0;
int au_rx_idx = 0;
pj_status_t status = PJ_SUCCESS;
PJ_ASSERT_RETURN(tp && tx && rx, PJ_EINVAL);
pj_lock_acquire(srtp->mutex);
if (srtp->session_inited) {
pjmedia_transport_srtp_stop(tp);
}
/* Get encryption and authentication method */
cr_tx_idx = au_tx_idx = get_crypto_idx(&tx->name);
if (tx->flags & PJMEDIA_SRTP_NO_ENCRYPTION)
cr_tx_idx = 0;
if (tx->flags & PJMEDIA_SRTP_NO_AUTHENTICATION)
au_tx_idx = 0;
cr_rx_idx = au_rx_idx = get_crypto_idx(&rx->name);
if (rx->flags & PJMEDIA_SRTP_NO_ENCRYPTION)
cr_rx_idx = 0;
if (rx->flags & PJMEDIA_SRTP_NO_AUTHENTICATION)
au_rx_idx = 0;
/* Check whether the crypto-suite requested is supported */
if (cr_tx_idx == -1 || cr_rx_idx == -1 || au_tx_idx == -1 ||
au_rx_idx == -1)
{
status = PJMEDIA_SRTP_ENOTSUPCRYPTO;
goto on_return;
}
/* If all options points to 'NULL' method, just bypass SRTP */
if (cr_tx_idx == 0 && cr_rx_idx == 0 && au_tx_idx == 0 && au_rx_idx == 0) {
srtp->bypass_srtp = PJ_TRUE;
goto on_return;
}
/* Check key length */
if (tx->key.slen != (pj_ssize_t)crypto_suites[cr_tx_idx].cipher_key_len ||
rx->key.slen != (pj_ssize_t)crypto_suites[cr_rx_idx].cipher_key_len)
{
status = PJMEDIA_SRTP_EINKEYLEN;
goto on_return;
}
/* Init transmit direction */
pj_bzero(&tx_, sizeof(srtp_policy_t));
pj_memmove(srtp->tx_key, tx->key.ptr, tx->key.slen);
if (cr_tx_idx && au_tx_idx)
tx_.rtp.sec_serv = sec_serv_conf_and_auth;
else if (cr_tx_idx)
tx_.rtp.sec_serv = sec_serv_conf;
else if (au_tx_idx)
tx_.rtp.sec_serv = sec_serv_auth;
else
tx_.rtp.sec_serv = sec_serv_none;
tx_.key = (uint8_t*)srtp->tx_key;
tx_.ssrc.type = ssrc_any_outbound;
tx_.ssrc.value = 0;
tx_.rtp.cipher_type = crypto_suites[cr_tx_idx].cipher_type;
tx_.rtp.cipher_key_len = crypto_suites[cr_tx_idx].cipher_key_len;
tx_.rtp.auth_type = crypto_suites[au_tx_idx].auth_type;
tx_.rtp.auth_key_len = crypto_suites[au_tx_idx].auth_key_len;
tx_.rtp.auth_tag_len = crypto_suites[au_tx_idx].srtp_auth_tag_len;
tx_.rtcp = tx_.rtp;
tx_.rtcp.auth_tag_len = crypto_suites[au_tx_idx].srtcp_auth_tag_len;
tx_.next = NULL;
err = srtp_create(&srtp->srtp_tx_ctx, &tx_);
if (err != err_status_ok) {
status = PJMEDIA_ERRNO_FROM_LIBSRTP(err);
goto on_return;
}
srtp->tx_policy = *tx;
pj_strset(&srtp->tx_policy.key, srtp->tx_key, tx->key.slen);
srtp->tx_policy.name=pj_str(crypto_suites[get_crypto_idx(&tx->name)].name);
/* Init receive direction */
pj_bzero(&rx_, sizeof(srtp_policy_t));
pj_memmove(srtp->rx_key, rx->key.ptr, rx->key.slen);
if (cr_rx_idx && au_rx_idx)
rx_.rtp.sec_serv = sec_serv_conf_and_auth;
else if (cr_rx_idx)
rx_.rtp.sec_serv = sec_serv_conf;
else if (au_rx_idx)
rx_.rtp.sec_serv = sec_serv_auth;
else
rx_.rtp.sec_serv = sec_serv_none;
rx_.key = (uint8_t*)srtp->rx_key;
rx_.ssrc.type = ssrc_any_inbound;
rx_.ssrc.value = 0;
rx_.rtp.sec_serv = crypto_suites[cr_rx_idx].service;
rx_.rtp.cipher_type = crypto_suites[cr_rx_idx].cipher_type;
rx_.rtp.cipher_key_len = crypto_suites[cr_rx_idx].cipher_key_len;
rx_.rtp.auth_type = crypto_suites[au_rx_idx].auth_type;
rx_.rtp.auth_key_len = crypto_suites[au_rx_idx].auth_key_len;
rx_.rtp.auth_tag_len = crypto_suites[au_rx_idx].srtp_auth_tag_len;
rx_.rtcp = rx_.rtp;
rx_.rtcp.auth_tag_len = crypto_suites[au_rx_idx].srtcp_auth_tag_len;
rx_.next = NULL;
err = srtp_create(&srtp->srtp_rx_ctx, &rx_);
if (err != err_status_ok) {
srtp_dealloc(srtp->srtp_tx_ctx);
status = PJMEDIA_ERRNO_FROM_LIBSRTP(err);
goto on_return;
}
srtp->rx_policy = *rx;
pj_strset(&srtp->rx_policy.key, srtp->rx_key, rx->key.slen);
srtp->rx_policy.name=pj_str(crypto_suites[get_crypto_idx(&rx->name)].name);
/* Declare SRTP session initialized */
srtp->session_inited = PJ_TRUE;
/* Logging stuffs */
#if PJ_LOG_MAX_LEVEL >= 5
{
char b64[PJ_BASE256_TO_BASE64_LEN(MAX_KEY_LEN)];
int b64_len;
/* TX crypto and key */
b64_len = sizeof(b64);
status = pj_base64_encode((pj_uint8_t*)tx->key.ptr, tx->key.slen,
b64, &b64_len);
if (status != PJ_SUCCESS)
b64_len = pj_ansi_sprintf(b64, "--key too long--");
else
b64[b64_len] = '\0';
PJ_LOG(5, (srtp->pool->obj_name, "TX: %s key=%s",
srtp->tx_policy.name.ptr, b64));
if (srtp->tx_policy.flags) {
PJ_LOG(5,(srtp->pool->obj_name, "TX: disable%s%s",
(cr_tx_idx?"":" enc"),
(au_tx_idx?"":" auth")));
}
/* RX crypto and key */
b64_len = sizeof(b64);
status = pj_base64_encode((pj_uint8_t*)rx->key.ptr, rx->key.slen,
b64, &b64_len);
if (status != PJ_SUCCESS)
b64_len = pj_ansi_sprintf(b64, "--key too long--");
else
b64[b64_len] = '\0';
PJ_LOG(5, (srtp->pool->obj_name, "RX: %s key=%s",
srtp->rx_policy.name.ptr, b64));
if (srtp->rx_policy.flags) {
PJ_LOG(5,(srtp->pool->obj_name,"RX: disable%s%s",
(cr_rx_idx?"":" enc"),
(au_rx_idx?"":" auth")));
}
}
#endif
on_return:
pj_lock_release(srtp->mutex);
return status;
}
