/* Checks whether the received packet contains a handshake
* packet with sequence higher that the previously received.
* It must be called only when an actual packet has been
* received.
*
* Returns: 0 if expected, negative value otherwise.
*/
static int is_next_hpacket_expected(gnutls_session_t session)
{
int ret;
/* htype is arbitrary */
ret = _gnutls_recv_in_buffers(session, GNUTLS_HANDSHAKE, GNUTLS_HANDSHAKE_FINISHED, 0);
if (ret < 0)
return gnutls_assert_val(ret);
ret = _gnutls_parse_record_buffered_msgs(session);
if (ret < 0)
return gnutls_assert_val(ret);
if (session->internals.handshake_recv_buffer_size > 0)
return 0;
else
return gnutls_assert_val(GNUTLS_E_UNEXPECTED_HANDSHAKE_PACKET);
}
/* This is a receive function for the gnutls handshake
* protocol. Makes sure that we have received all data.
*/
ssize_t
_gnutls_handshake_io_recv_int(gnutls_session_t session,
gnutls_handshake_description_t htype,
handshake_buffer_st * hsk,
unsigned int optional)
{
int ret;
unsigned int tleft = 0;
int retries = 7;
ret = get_last_packet(session, htype, hsk, optional);
if (ret != GNUTLS_E_AGAIN && ret != GNUTLS_E_INTERRUPTED &&
ret != GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE &&
ret != GNUTLS_E_INT_CHECK_AGAIN) {
return gnutls_assert_val(ret);
}
/* try using the already existing records before
* trying to receive.
*/
ret = _gnutls_parse_record_buffered_msgs(session);
if (ret == 0) {
ret = get_last_packet(session, htype, hsk, optional);
}
if (IS_DTLS(session)) {
if (ret >= 0)
return ret;
} else {
if ((ret != GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE
&& ret < 0) || ret >= 0)
return gnutls_assert_val(ret);
}
if (htype != (gnutls_handshake_description_t) -1) {
ret = handshake_remaining_time(session);
if (ret < 0)
return gnutls_assert_val(ret);
tleft = ret;
}
do {
/* if we don't have a complete message waiting for us, try
* receiving more */
ret =
_gnutls_recv_in_buffers(session, GNUTLS_HANDSHAKE, htype,
tleft);
if (ret < 0)
return gnutls_assert_val_fatal(ret);
ret = _gnutls_parse_record_buffered_msgs(session);
if (ret == 0) {
ret = get_last_packet(session, htype, hsk, optional);
}
/* we put an upper limit (retries) to the number of partial handshake
* messages in a record packet. */
} while(IS_DTLS(session) && ret == GNUTLS_E_INT_CHECK_AGAIN && retries-- > 0);
if (unlikely(IS_DTLS(session) && ret == GNUTLS_E_INT_CHECK_AGAIN)) {
ret = gnutls_assert_val(GNUTLS_E_TOO_MANY_HANDSHAKE_PACKETS);
}
return ret;
}
