int
_gnutls_epoch_set_cipher_suite (gnutls_session_t session,
int epoch_rel, cipher_suite_st * suite)
{
gnutls_cipher_algorithm_t cipher_algo;
gnutls_mac_algorithm_t mac_algo;
record_parameters_st *params;
int ret;
ret = _gnutls_epoch_get (session, epoch_rel, ¶ms);
if (ret < 0)
return gnutls_assert_val (ret);
if (params->initialized
|| params->cipher_algorithm != GNUTLS_CIPHER_UNKNOWN
|| params->mac_algorithm != GNUTLS_MAC_UNKNOWN)
return gnutls_assert_val (GNUTLS_E_INTERNAL_ERROR);
cipher_algo = _gnutls_cipher_suite_get_cipher_algo (suite);
mac_algo = _gnutls_cipher_suite_get_mac_algo (suite);
if (_gnutls_cipher_is_ok (cipher_algo) != 0
|| _gnutls_mac_is_ok (mac_algo) != 0)
return gnutls_assert_val (GNUTLS_E_UNWANTED_ALGORITHM);
params->cipher_algorithm = cipher_algo;
params->mac_algorithm = mac_algo;
return 0;
}
int
_gnutls_epoch_set_compression(gnutls_session_t session,
int epoch_rel,
gnutls_compression_method_t comp_algo)
{
record_parameters_st *params;
int ret;
ret = _gnutls_epoch_get(session, epoch_rel, ¶ms);
if (ret < 0)
return gnutls_assert_val(ret);
if (params->initialized
|| params->compression_algorithm != GNUTLS_COMP_UNKNOWN)
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
if (_gnutls_compression_is_ok(comp_algo) != 0)
return
gnutls_assert_val
(GNUTLS_E_UNKNOWN_COMPRESSION_ALGORITHM);
params->compression_algorithm = comp_algo;
return 0;
}
int
_gnutls_epoch_set_keys (gnutls_session_t session, uint16_t epoch)
{
int hash_size;
int IV_size;
int key_size, export_flag;
gnutls_cipher_algorithm_t cipher_algo;
gnutls_mac_algorithm_t mac_algo;
gnutls_compression_method_t comp_algo;
record_parameters_st *params;
int ret;
gnutls_protocol_t ver = gnutls_protocol_get_version (session);
ret = _gnutls_epoch_get (session, epoch, ¶ms);
if (ret < 0)
return gnutls_assert_val (ret);
if (params->initialized)
return 0;
_gnutls_record_log
("REC[%p]: Initializing epoch #%u\n", session, params->epoch);
cipher_algo = params->cipher_algorithm;
mac_algo = params->mac_algorithm;
comp_algo = params->compression_algorithm;
if (_gnutls_cipher_is_ok (cipher_algo) != 0
|| _gnutls_mac_is_ok (mac_algo) != 0)
return gnutls_assert_val (GNUTLS_E_INTERNAL_ERROR);
if (_gnutls_compression_is_ok (comp_algo) != 0)
return gnutls_assert_val (GNUTLS_E_UNKNOWN_COMPRESSION_ALGORITHM);
IV_size = _gnutls_cipher_get_iv_size (cipher_algo);
key_size = gnutls_cipher_get_key_size (cipher_algo);
export_flag = _gnutls_cipher_get_export_flag (cipher_algo);
hash_size = _gnutls_hmac_get_algo_len (mac_algo);
ret = _gnutls_set_keys
(session, params, hash_size, IV_size, key_size, export_flag);
if (ret < 0)
return gnutls_assert_val (ret);
ret = _gnutls_init_record_state (params, ver, 1, ¶ms->read);
if (ret < 0)
return gnutls_assert_val (ret);
ret = _gnutls_init_record_state (params, ver, 0, ¶ms->write);
if (ret < 0)
return gnutls_assert_val (ret);
params->record_sw_size = 0;
_gnutls_record_log ("REC[%p]: Epoch #%u ready\n", session, params->epoch);
params->initialized = 1;
return 0;
}
int _gnutls_epoch_get_compression(gnutls_session_t session, int epoch)
{
record_parameters_st *params;
int ret;
ret = _gnutls_epoch_get (session, epoch, ¶ms);
if (ret < 0)
return GNUTLS_COMP_UNKNOWN;
return params->compression_algorithm;
}
inline static int
is_read_comp_null (gnutls_session_t session)
{
record_parameters_st *record_params;
_gnutls_epoch_get (session, EPOCH_READ_CURRENT, &record_params);
if (record_params->compression_algorithm == GNUTLS_COMP_NULL)
return 0;
return 1;
}
/**
* gnutls_compression_get:
* @session: is a #gnutls_session_t structure.
*
* Get currently used compression algorithm.
*
* Returns: the currently used compression method, a
* #gnutls_compression_method_t value.
**/
gnutls_compression_method_t
gnutls_compression_get (gnutls_session_t session)
{
record_parameters_st *record_params;
int ret;
ret = _gnutls_epoch_get (session, EPOCH_READ_CURRENT, &record_params);
if (ret < 0)
return gnutls_assert_val(GNUTLS_COMP_NULL);
return record_params->compression_algorithm;
}
/**
* gnutls_mac_get:
* @session: is a #gnutls_session_t structure.
*
* Get currently used MAC algorithm.
*
* Returns: the currently used mac algorithm, a
* #gnutls_mac_algorithm_t value.
**/
gnutls_mac_algorithm_t
gnutls_mac_get (gnutls_session_t session)
{
record_parameters_st *record_params;
int ret;
ret = _gnutls_epoch_get (session, EPOCH_READ_CURRENT, &record_params);
if (ret < 0)
return gnutls_assert_val(GNUTLS_MAC_NULL);
return record_params->mac_algorithm;
}
/**
* gnutls_cipher_get:
* @session: is a #gnutls_session_t structure.
*
* Get currently used cipher.
*
* Returns: the currently used cipher, a #gnutls_cipher_algorithm_t
* type.
**/
gnutls_cipher_algorithm_t gnutls_cipher_get(gnutls_session_t session)
{
record_parameters_st *record_params;
int ret;
ret =
_gnutls_epoch_get(session, EPOCH_READ_CURRENT, &record_params);
if (ret < 0)
return gnutls_assert_val(GNUTLS_CIPHER_NULL);
return record_params->cipher->id;
}
/* returns overhead imposed by the record layer (encryption/compression)
* etc. It does not include the record layer headers, since the caller
* needs to cope with rounding to multiples of blocksize, and the header
* is outside that.
*
* blocksize: will contain the block size when padding may be required or 1
*
* It may return a negative error code on error.
*/
static int record_overhead_rt(gnutls_session_t session, unsigned int *blocksize)
{
record_parameters_st *params;
int total = 0, ret, iv_size;
if (session->internals.initial_negotiation_completed == 0)
return GNUTLS_E_INVALID_REQUEST;
ret = _gnutls_epoch_get (session, EPOCH_WRITE_CURRENT, ¶ms);
if (ret < 0)
return gnutls_assert_val(ret);
/* requires padding */
iv_size = _gnutls_cipher_get_iv_size(params->cipher_algorithm);
if (_gnutls_cipher_is_block (params->cipher_algorithm) == CIPHER_BLOCK)
{
*blocksize = iv_size;
total += iv_size; /* iv_size == block_size in DTLS */
/* We always pad with at least one byte; never 0. */
total++;
}
else
{
*blocksize = 1;
}
if (params->mac_algorithm == GNUTLS_MAC_AEAD)
total += _gnutls_cipher_get_tag_size(params->cipher_algorithm);
else
{
ret = _gnutls_hmac_get_algo_len(params->mac_algorithm);
if (ret < 0)
return gnutls_assert_val(ret);
total+=ret;
}
if (params->compression_algorithm != GNUTLS_COMP_NULL)
total += EXTRA_COMP_SIZE;
return total;
}
/**
* gnutls_dtls_prestate_set:
* @session: a new session
* @prestate: contains the client's prestate
*
* This function will associate the prestate acquired by
* the cookie authentication with the client, with the newly
* established session.
*
* Since: 3.0
**/
void gnutls_dtls_prestate_set(gnutls_session_t session, gnutls_dtls_prestate_st* prestate)
{
record_parameters_st *params;
int ret;
if (prestate == NULL)
return;
/* we do not care about read_params, since we accept anything
* the peer sends.
*/
ret = _gnutls_epoch_get (session, EPOCH_WRITE_CURRENT, ¶ms);
if (ret < 0)
return;
params->write.sequence_number.i[7] = prestate->record_seq;
session->internals.dtls.hsk_read_seq = prestate->hsk_read_seq;
session->internals.dtls.hsk_write_seq = prestate->hsk_write_seq + 1;
}
int
_gnutls_epoch_set_cipher_suite(gnutls_session_t session,
int epoch_rel, const uint8_t suite[2])
{
const cipher_entry_st *cipher_algo;
const mac_entry_st *mac_algo;
record_parameters_st *params;
const gnutls_cipher_suite_entry_st *cs;
int ret;
ret = _gnutls_epoch_get(session, epoch_rel, ¶ms);
if (ret < 0)
return gnutls_assert_val(ret);
if (params->initialized
|| params->cipher != NULL || params->mac != NULL)
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
cs = ciphersuite_to_entry(suite);
if (cs == NULL)
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
cipher_algo = cipher_to_entry(cs->block_algorithm);
mac_algo = mac_to_entry(cs->mac_algorithm);
if (_gnutls_cipher_is_ok(cipher_algo) == 0
|| _gnutls_mac_is_ok(mac_algo) == 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
if (_gnutls_cipher_priority(session, cipher_algo->id) < 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
if (_gnutls_mac_priority(session, mac_algo->id) < 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
params->cipher = cipher_algo;
params->mac = mac_algo;
return 0;
}
/* Format:
* 4 bytes the total security data size
* 1 byte the entity type (client/server)
* 1 byte the key exchange algorithm used
* 1 byte the read cipher algorithm
* 1 byte the read mac algorithm
* 1 byte the read compression algorithm
*
* 1 byte the write cipher algorithm
* 1 byte the write mac algorithm
* 1 byte the write compression algorithm
*
* 1 byte the certificate type
* 1 byte the protocol version
*
* 2 bytes the cipher suite
*
* 48 bytes the master secret
*
* 32 bytes the client random
* 32 bytes the server random
*
* 1 byte the session ID size
* x bytes the session ID (32 bytes max)
*
* 4 bytes a timestamp
* -------------------
* MAX: 165 bytes
*
*/
static int
pack_security_parameters (gnutls_session_t session, gnutls_buffer_st * ps)
{
int ret;
int size_offset;
size_t cur_size;
record_parameters_st *params;
if (session->security_parameters.epoch_read
!= session->security_parameters.epoch_write)
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
ret = _gnutls_epoch_get (session, EPOCH_READ_CURRENT, ¶ms);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
/* move after the auth info stuff.
*/
size_offset = ps->length;
BUFFER_APPEND_NUM (ps, 0);
cur_size = ps->length;
BUFFER_APPEND (ps, &session->security_parameters.entity, 1);
BUFFER_APPEND (ps, &session->security_parameters.kx_algorithm, 1);
BUFFER_APPEND (ps,
&session->security_parameters.current_cipher_suite.suite[0],
1);
BUFFER_APPEND (ps,
&session->security_parameters.current_cipher_suite.suite[1],
1);
BUFFER_APPEND (ps, ¶ms->compression_algorithm, 1);
BUFFER_APPEND (ps, &session->security_parameters.cert_type, 1);
BUFFER_APPEND (ps, &session->security_parameters.version, 1);
BUFFER_APPEND (ps, session->security_parameters.master_secret,
GNUTLS_MASTER_SIZE);
BUFFER_APPEND (ps, session->security_parameters.client_random,
GNUTLS_RANDOM_SIZE);
BUFFER_APPEND (ps, session->security_parameters.server_random,
GNUTLS_RANDOM_SIZE);
BUFFER_APPEND_NUM (ps, session->security_parameters.session_id_size);
BUFFER_APPEND (ps, session->security_parameters.session_id,
session->security_parameters.session_id_size);
BUFFER_APPEND_NUM (ps, session->security_parameters.max_record_send_size);
BUFFER_APPEND_NUM (ps, session->security_parameters.max_record_recv_size);
BUFFER_APPEND_NUM (ps, session->security_parameters.timestamp);
_gnutls_write_uint32 (ps->length - cur_size, ps->data + size_offset);
return 0;
}
int _gnutls_epoch_set_keys(gnutls_session_t session, uint16_t epoch)
{
int hash_size;
int IV_size;
int key_size;
gnutls_compression_method_t comp_algo;
record_parameters_st *params;
int ret;
const version_entry_st *ver = get_version(session);
if (unlikely(ver == NULL))
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
ret = _gnutls_epoch_get(session, epoch, ¶ms);
if (ret < 0)
return gnutls_assert_val(ret);
if (params->initialized)
return 0;
_gnutls_record_log
("REC[%p]: Initializing epoch #%u\n", session, params->epoch);
comp_algo = params->compression_algorithm;
if (_gnutls_cipher_is_ok(params->cipher) == 0
|| _gnutls_mac_is_ok(params->mac) == 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
if (_gnutls_cipher_priority(session, params->cipher->id) < 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
if (_gnutls_mac_priority(session, params->mac->id) < 0)
return gnutls_assert_val(GNUTLS_E_UNWANTED_ALGORITHM);
if (_gnutls_compression_is_ok(comp_algo) != 0)
return
gnutls_assert_val
(GNUTLS_E_UNKNOWN_COMPRESSION_ALGORITHM);
if (!_gnutls_version_has_explicit_iv(ver) &&
_gnutls_cipher_type(params->cipher) == CIPHER_BLOCK) {
IV_size = _gnutls_cipher_get_iv_size(params->cipher);
} else {
IV_size = _gnutls_cipher_get_implicit_iv_size(params->cipher);
}
key_size = _gnutls_cipher_get_key_size(params->cipher);
hash_size = _gnutls_mac_get_key_size(params->mac);
params->etm = session->security_parameters.etm;
ret = _gnutls_set_keys
(session, params, hash_size, IV_size, key_size);
if (ret < 0)
return gnutls_assert_val(ret);
ret = _gnutls_init_record_state(params, ver, 1, ¶ms->read);
if (ret < 0)
return gnutls_assert_val(ret);
ret = _gnutls_init_record_state(params, ver, 0, ¶ms->write);
if (ret < 0)
return gnutls_assert_val(ret);
params->record_sw_size = 0;
_gnutls_record_log("REC[%p]: Epoch #%u ready\n", session,
params->epoch);
params->initialized = 1;
return 0;
}
/* This function behaves exactly like write(). The only difference is
* that it accepts, the gnutls_session_t and the content_type_t of data to
* send (if called by the user the Content is specific)
* It is intended to transfer data, under the current session.
*
* Oct 30 2001: Removed capability to send data more than MAX_RECORD_SIZE.
* This makes the function much easier to read, and more error resistant
* (there were cases were the old function could mess everything up).
* --nmav
*
* This function may accept a NULL pointer for data, and 0 for size, if
* and only if the previous send was interrupted for some reason.
*
*/
ssize_t
_gnutls_send_int (gnutls_session_t session, content_type_t type,
gnutls_handshake_description_t htype,
unsigned int epoch_rel, const void *_data,
size_t sizeofdata, unsigned int mflags)
{
mbuffer_st *bufel;
ssize_t cipher_size;
int retval, ret;
int data2send_size;
uint8_t headers[5];
const uint8_t *data = _data;
record_parameters_st *record_params;
record_state_st *record_state;
ret = _gnutls_epoch_get (session, epoch_rel, &record_params);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
/* Safeguard against processing data with an incomplete cipher state. */
if (!record_params->initialized)
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
record_state = &record_params->write;
/* Do not allow null pointer if the send buffer is empty.
* If the previous send was interrupted then a null pointer is
* ok, and means to resume.
*/
if (session->internals.record_send_buffer.byte_length == 0 &&
(sizeofdata == 0 && _data == NULL))
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
if (type != GNUTLS_ALERT) /* alert messages are sent anyway */
if (session_is_valid (session) || session->internals.may_not_write != 0)
{
gnutls_assert ();
return GNUTLS_E_INVALID_SESSION;
}
headers[0] = type;
/* Use the default record version, if it is
* set.
*/
copy_record_version (session, htype, &headers[1]);
_gnutls_record_log
("REC[%p]: Sending Packet[%d] %s(%d) with length: %d\n", session,
(int) _gnutls_uint64touint32 (&record_state->sequence_number),
_gnutls_packet2str (type), type, (int) sizeofdata);
if (sizeofdata > MAX_RECORD_SEND_SIZE)
data2send_size = MAX_RECORD_SEND_SIZE;
else
data2send_size = sizeofdata;
/* Only encrypt if we don't have data to send
* from the previous run. - probably interrupted.
*/
if (mflags != 0 && session->internals.record_send_buffer.byte_length > 0)
{
ret = _gnutls_io_write_flush (session);
if (ret > 0)
cipher_size = ret;
else
cipher_size = 0;
retval = session->internals.record_send_buffer_user_size;
}
else
{
/* now proceed to packet encryption
*/
cipher_size = data2send_size + MAX_RECORD_OVERHEAD;
bufel = _mbuffer_alloc (cipher_size, cipher_size);
if (bufel == NULL)
{
gnutls_assert ();
return GNUTLS_E_MEMORY_ERROR;
}
cipher_size =
_gnutls_encrypt (session, headers, RECORD_HEADER_SIZE, data,
data2send_size, _mbuffer_get_udata_ptr (bufel),
cipher_size, type,
(session->internals.priorities.no_padding ==
0) ? 1 : 0, record_params);
if (cipher_size <= 0)
{
gnutls_assert ();
if (cipher_size == 0)
cipher_size = GNUTLS_E_ENCRYPTION_FAILED;
gnutls_free (bufel);
return cipher_size; /* error */
}
retval = data2send_size;
session->internals.record_send_buffer_user_size = data2send_size;
/* increase sequence number
*/
if (_gnutls_uint64pp (&record_state->sequence_number) != 0)
{
session_invalidate (session);
gnutls_assert ();
gnutls_free (bufel);
return GNUTLS_E_RECORD_LIMIT_REACHED;
}
_mbuffer_set_udata_size (bufel, cipher_size);
ret = _gnutls_io_write_buffered (session, bufel, mflags);
}
if (ret != cipher_size)
{
if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
{
/* If we have sent any data then just return
* the error value. Do not invalidate the session.
*/
gnutls_assert ();
return ret;
}
if (ret > 0)
{
gnutls_assert ();
ret = GNUTLS_E_INTERNAL_ERROR;
}
session_unresumable (session);
session->internals.may_not_write = 1;
gnutls_assert ();
return ret;
}
session->internals.record_send_buffer_user_size = 0;
_gnutls_record_log ("REC[%p]: Sent Packet[%d] %s(%d) with length: %d\n",
session,
(int)
_gnutls_uint64touint32
(&record_state->sequence_number),
_gnutls_packet2str (type), type, (int) cipher_size);
return retval;
}
/* This function behaves exactly like read(). The only difference is
* that it accepts the gnutls_session_t and the content_type_t of data to
* receive (if called by the user the Content is Userdata only)
* It is intended to receive data, under the current session.
*
* The gnutls_handshake_description_t was introduced to support SSL V2.0 client hellos.
*/
ssize_t
_gnutls_recv_int (gnutls_session_t session, content_type_t type,
gnutls_handshake_description_t htype,
opaque * data, size_t sizeofdata)
{
int decrypted_length;
opaque version[2];
content_type_t recv_type;
uint16_t length;
uint8_t *ciphertext;
int ret, ret2;
uint16_t header_size;
int empty_packet = 0;
gnutls_datum_t data_enc, tmp;
record_parameters_st *record_params;
record_state_st *record_state;
ret = _gnutls_epoch_get (session, EPOCH_READ_CURRENT, &record_params);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
/* Safeguard against processing data with an incomplete cipher state. */
if (!record_params->initialized)
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
record_state = &record_params->read;
if (type != GNUTLS_ALERT && (sizeofdata == 0 || data == NULL))
{
return GNUTLS_E_INVALID_REQUEST;
}
begin:
if (empty_packet > MAX_EMPTY_PACKETS_SEQUENCE)
{
gnutls_assert ();
return GNUTLS_E_TOO_MANY_EMPTY_PACKETS;
}
if (session->internals.read_eof != 0)
{
/* if we have already read an EOF
*/
return 0;
}
else if (session_is_valid (session) != 0
|| session->internals.may_not_read != 0)
{
gnutls_assert ();
return GNUTLS_E_INVALID_SESSION;
}
/* If we have enough data in the cache do not bother receiving
* a new packet. (in order to flush the cache)
*/
ret = check_buffers (session, type, data, sizeofdata);
if (ret != 0)
return ret;
/* default headers for TLS 1.0
*/
header_size = RECORD_HEADER_SIZE;
if ((ret =
_gnutls_io_read_buffered (session, header_size, -1)) != header_size)
{
if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
return ret;
session_invalidate (session);
if (type == GNUTLS_ALERT)
{
gnutls_assert ();
return 0; /* we were expecting close notify */
}
session_unresumable (session);
gnutls_assert ();
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
ret = _mbuffer_linearize (&session->internals.record_recv_buffer);
if (ret != 0)
{
gnutls_assert ();
return ret;
}
_mbuffer_get_first (&session->internals.record_recv_buffer, &data_enc);
if ((ret =
record_check_headers (session, data_enc.data, type, htype, &recv_type,
version, &length, &header_size)) < 0)
{
gnutls_assert ();
return ret;
}
/* Here we check if the Type of the received packet is
* ok.
*/
if ((ret = check_recv_type (recv_type)) < 0)
{
gnutls_assert ();
return ret;
}
/* Here we check if the advertized version is the one we
* negotiated in the handshake.
*/
if ((ret = record_check_version (session, htype, version)) < 0)
{
gnutls_assert ();
session_invalidate (session);
return ret;
}
_gnutls_record_log
("REC[%p]: Expected Packet[%d] %s(%d) with length: %d\n", session,
(int) _gnutls_uint64touint32 (&record_state->sequence_number),
_gnutls_packet2str (type), type, (int) sizeofdata);
_gnutls_record_log ("REC[%p]: Received Packet[%d] %s(%d) with length: %d\n",
session,
(int)
_gnutls_uint64touint32 (&record_state->sequence_number),
_gnutls_packet2str (recv_type), recv_type, length);
if (length > MAX_RECV_SIZE)
{
_gnutls_record_log
("REC[%p]: FATAL ERROR: Received packet with length: %d\n",
session, length);
session_unresumable (session);
session_invalidate (session);
gnutls_assert ();
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
/* check if we have that data into buffer.
*/
if ((ret =
_gnutls_io_read_buffered (session, header_size + length,
recv_type)) != header_size + length)
{
if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
return ret;
session_unresumable (session);
session_invalidate (session);
gnutls_assert ();
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
/* ok now we are sure that we can read all the data - so
* move on !
*/
ret = _mbuffer_linearize (&session->internals.record_recv_buffer);
if (ret != 0)
{
gnutls_assert ();
return ret;
}
_mbuffer_get_first (&session->internals.record_recv_buffer, &data_enc);
ciphertext = &data_enc.data[header_size];
ret = get_temp_recv_buffer (session, &tmp);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
/* decrypt the data we got.
*/
ret =
_gnutls_decrypt (session, ciphertext, length, tmp.data, tmp.size,
recv_type, record_params);
if (ret < 0)
{
session_unresumable (session);
session_invalidate (session);
gnutls_assert ();
return ret;
}
_mbuffer_remove_bytes (&session->internals.record_recv_buffer,
header_size + length);
decrypted_length = ret;
/* Check if this is a CHANGE_CIPHER_SPEC
*/
if (type == GNUTLS_CHANGE_CIPHER_SPEC &&
recv_type == GNUTLS_CHANGE_CIPHER_SPEC)
{
_gnutls_record_log
("REC[%p]: ChangeCipherSpec Packet was received\n", session);
if ((size_t) ret != sizeofdata)
{ /* sizeofdata should be 1 */
gnutls_assert ();
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
memcpy (data, tmp.data, sizeofdata);
return ret;
}
_gnutls_record_log
("REC[%p]: Decrypted Packet[%d] %s(%d) with length: %d\n", session,
(int) _gnutls_uint64touint32 (&record_state->sequence_number),
_gnutls_packet2str (recv_type), recv_type, decrypted_length);
/* increase sequence number
*/
if (_gnutls_uint64pp (&record_state->sequence_number) != 0)
{
session_invalidate (session);
gnutls_assert ();
return GNUTLS_E_RECORD_LIMIT_REACHED;
}
ret =
record_check_type (session, recv_type, type, htype, tmp.data,
decrypted_length);
if (ret < 0)
{
if (ret == GNUTLS_E_INT_RET_0)
return 0;
gnutls_assert ();
return ret;
}
/* Get Application data from buffer
*/
if ((recv_type == type) &&
(type == GNUTLS_APPLICATION_DATA ||
type == GNUTLS_HANDSHAKE || type == GNUTLS_INNER_APPLICATION))
{
ret = _gnutls_record_buffer_get (type, session, data, sizeofdata);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
/* if the buffer just got empty
*/
if (_gnutls_record_buffer_get_size (type, session) == 0)
{
if ((ret2 = _gnutls_io_clear_peeked_data (session)) < 0)
{
gnutls_assert ();
return ret2;
}
}
}
else
{
gnutls_assert ();
return GNUTLS_E_UNEXPECTED_PACKET;
/* we didn't get what we wanted to
*/
}
/* (originally for) TLS 1.0 CBC protection.
* Actually this code is called if we just received
* an empty packet. An empty TLS packet is usually
* sent to protect some vulnerabilities in the CBC mode.
* In that case we go to the beginning and start reading
* the next packet.
*/
if (ret == 0)
{
empty_packet++;
goto begin;
}
return ret;
}
/* @ms: is the number of milliseconds to wait for data. Use zero for indefinite.
*
* This will receive record layer packets and add them to
* application_data_buffer and handshake_data_buffer.
*
* If the htype is not -1 then handshake timeouts
* will be enforced.
*/
ssize_t
_gnutls_recv_in_buffers (gnutls_session_t session, content_type_t type,
gnutls_handshake_description_t htype, unsigned int ms)
{
uint64 *packet_sequence;
gnutls_datum_t ciphertext;
mbuffer_st* bufel = NULL, *decrypted = NULL;
gnutls_datum_t t;
int ret;
unsigned int empty_fragments = 0;
record_parameters_st *record_params;
record_state_st *record_state;
struct tls_record_st record;
begin:
if (empty_fragments > session->internals.priorities.max_empty_records)
{
gnutls_assert ();
return GNUTLS_E_TOO_MANY_EMPTY_PACKETS;
}
if (session->internals.read_eof != 0)
{
/* if we have already read an EOF
*/
return 0;
}
else if (session_is_valid (session) != 0
|| session->internals.may_not_read != 0)
return gnutls_assert_val(GNUTLS_E_INVALID_SESSION);
/* get the record state parameters */
ret = _gnutls_epoch_get (session, EPOCH_READ_CURRENT, &record_params);
if (ret < 0)
return gnutls_assert_val (ret);
/* Safeguard against processing data with an incomplete cipher state. */
if (!record_params->initialized)
return gnutls_assert_val (GNUTLS_E_INTERNAL_ERROR);
record_state = &record_params->read;
/* receive headers */
ret = recv_headers(session, type, htype, &record, &ms);
if (ret < 0)
{
ret = gnutls_assert_val_fatal(ret);
goto recv_error;
}
if (IS_DTLS(session))
packet_sequence = &record.sequence;
else
packet_sequence = &record_state->sequence_number;
/* Read the packet data and insert it to record_recv_buffer.
*/
ret =
_gnutls_io_read_buffered (session, record.packet_size,
record.type, &ms);
if (ret != record.packet_size)
{
gnutls_assert();
goto recv_error;
}
/* ok now we are sure that we have read all the data - so
* move on !
*/
ret = _mbuffer_linearize (&session->internals.record_recv_buffer);
if (ret < 0)
return gnutls_assert_val(ret);
bufel = _mbuffer_head_get_first (&session->internals.record_recv_buffer, NULL);
if (bufel == NULL)
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
/* We allocate the maximum possible to allow few compressed bytes to expand to a
* full record.
*/
decrypted = _mbuffer_alloc(record.length, record.length);
if (decrypted == NULL)
return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
ciphertext.data = (uint8_t*)_mbuffer_get_udata_ptr(bufel) + record.header_size;
ciphertext.size = record.length;
/* decrypt the data we got.
*/
t.data = _mbuffer_get_udata_ptr(decrypted);
t.size = _mbuffer_get_udata_size(decrypted);
ret =
_gnutls_decrypt (session, &ciphertext, &t,
record.type, record_params, packet_sequence);
if (ret >= 0) _mbuffer_set_udata_size(decrypted, ret);
_mbuffer_head_remove_bytes (&session->internals.record_recv_buffer,
record.header_size + record.length);
if (ret < 0)
{
gnutls_assert();
_gnutls_audit_log(session, "Discarded message[%u] due to invalid decryption\n",
(unsigned int)_gnutls_uint64touint32 (packet_sequence));
goto sanity_check_error;
}
/* check for duplicates. We check after the message
* is processed and authenticated to avoid someone
* messing with our windows.
*/
if (IS_DTLS(session) && session->internals.no_replay_protection == 0)
{
ret = _dtls_record_check(record_params, packet_sequence);
if (ret < 0)
{
_gnutls_audit_log(session, "Discarded duplicate message[%u.%u]: %s\n",
(unsigned int)record.sequence.i[0]*256 +(unsigned int)record.sequence.i[1],
(unsigned int) _gnutls_uint64touint32 (packet_sequence), _gnutls_packet2str (record.type));
goto sanity_check_error;
}
_gnutls_record_log
("REC[%p]: Decrypted Packet[%u.%u] %s(%d) with length: %d\n", session,
(unsigned int)record.sequence.i[0]*256 +(unsigned int)record.sequence.i[1],
(unsigned int) _gnutls_uint64touint32 (packet_sequence),
_gnutls_packet2str (record.type), record.type, (int)_mbuffer_get_udata_size(decrypted));
}
else
{
_gnutls_record_log
("REC[%p]: Decrypted Packet[%u] %s(%d) with length: %d\n", session,
(unsigned int) _gnutls_uint64touint32 (packet_sequence),
_gnutls_packet2str (record.type), record.type, (int)_mbuffer_get_udata_size(decrypted));
}
/* increase sequence number
*/
if (!IS_DTLS(session) && sequence_increment (session, &record_state->sequence_number) != 0)
{
session_invalidate (session);
gnutls_assert ();
ret = GNUTLS_E_RECORD_LIMIT_REACHED;
goto sanity_check_error;
}
/* (originally for) TLS 1.0 CBC protection.
* Actually this code is called if we just received
* an empty packet. An empty TLS packet is usually
* sent to protect some vulnerabilities in the CBC mode.
* In that case we go to the beginning and start reading
* the next packet.
*/
if (_mbuffer_get_udata_size(decrypted) == 0)
{
_mbuffer_xfree(&decrypted);
empty_fragments++;
goto begin;
}
if (record.v2)
decrypted->htype = GNUTLS_HANDSHAKE_CLIENT_HELLO_V2;
else
{
uint8_t * p = _mbuffer_get_udata_ptr(decrypted);
decrypted->htype = p[0];
}
ret =
record_add_to_buffers (session, &record, type, htype,
packet_sequence, decrypted);
/* bufel is now either deinitialized or buffered somewhere else */
if (ret < 0)
return gnutls_assert_val(ret);
return ret;
discard:
session->internals.dtls.packets_dropped++;
/* discard the whole received fragment. */
bufel = _mbuffer_head_pop_first(&session->internals.record_recv_buffer);
_mbuffer_xfree(&bufel);
return gnutls_assert_val(GNUTLS_E_AGAIN);
sanity_check_error:
if (IS_DTLS(session))
{
session->internals.dtls.packets_dropped++;
ret = gnutls_assert_val(GNUTLS_E_AGAIN);
goto cleanup;
}
session_unresumable (session);
session_invalidate (session);
cleanup:
_mbuffer_xfree(&decrypted);
return ret;
recv_error:
if (ret < 0 && (gnutls_error_is_fatal (ret) == 0 || ret == GNUTLS_E_TIMEDOUT))
return ret;
if (type == GNUTLS_ALERT) /* we were expecting close notify */
{
session_invalidate (session);
gnutls_assert ();
return 0;
}
if (IS_DTLS(session))
{
goto discard;
}
session_invalidate (session);
session_unresumable (session);
if (ret == 0)
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
else
return ret;
}
/* This function behaves exactly like write(). The only difference is
* that it accepts, the gnutls_session_t and the content_type_t of data to
* send (if called by the user the Content is specific)
* It is intended to transfer data, under the current session.
*
* @type: The content type to send
* @htype: If this is a handshake message then the handshake type
* @epoch_rel: %EPOCH_READ_* or %EPOCH_WRITE_*
* @data: the data to be sent
* @data_size: the size of the @data
* @target_length: @data_size + minimum required padding
* @mflags: zero or %MBUFFER_FLUSH
*
* Oct 30 2001: Removed capability to send data more than MAX_RECORD_SIZE.
* This makes the function much easier to read, and more error resistant
* (there were cases were the old function could mess everything up).
* --nmav
*
* This function may accept a NULL pointer for data, and 0 for size, if
* and only if the previous send was interrupted for some reason.
*
*/
ssize_t
_gnutls_send_tlen_int (gnutls_session_t session, content_type_t type,
gnutls_handshake_description_t htype,
unsigned int epoch_rel, const void *_data,
size_t data_size, size_t target_length, unsigned int mflags)
{
mbuffer_st *bufel;
ssize_t cipher_size;
int retval, ret;
int send_data_size;
uint8_t *headers;
int header_size;
const uint8_t *data = _data;
record_parameters_st *record_params;
record_state_st *record_state;
ret = _gnutls_epoch_get (session, epoch_rel, &record_params);
if (ret < 0)
return gnutls_assert_val(ret);
/* Safeguard against processing data with an incomplete cipher state. */
if (!record_params->initialized)
return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);
record_state = &record_params->write;
/* Do not allow null pointer if the send buffer is empty.
* If the previous send was interrupted then a null pointer is
* ok, and means to resume.
*/
if (session->internals.record_send_buffer.byte_length == 0 &&
(data_size == 0 && _data == NULL))
{
gnutls_assert ();
return GNUTLS_E_INVALID_REQUEST;
}
if (type != GNUTLS_ALERT) /* alert messages are sent anyway */
if (session_is_valid (session) || session->internals.may_not_write != 0)
{
gnutls_assert ();
return GNUTLS_E_INVALID_SESSION;
}
if (data_size > MAX_USER_SEND_SIZE(session))
{
if (IS_DTLS(session))
return gnutls_assert_val(GNUTLS_E_LARGE_PACKET);
send_data_size = MAX_USER_SEND_SIZE(session);
}
else
send_data_size = data_size;
/* Only encrypt if we don't have data to send
* from the previous run. - probably interrupted.
*/
if (mflags != 0 && session->internals.record_send_buffer.byte_length > 0)
{
ret = _gnutls_io_write_flush (session);
if (ret > 0)
cipher_size = ret;
else
cipher_size = 0;
retval = session->internals.record_send_buffer_user_size;
}
else
{
if (unlikely((send_data_size == 0 && target_length == 0)))
return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
/* now proceed to packet encryption
*/
cipher_size = MAX_RECORD_SEND_SIZE(session);
bufel = _mbuffer_alloc (0, cipher_size+CIPHER_SLACK_SIZE);
if (bufel == NULL)
return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
headers = _mbuffer_get_uhead_ptr(bufel);
headers[0] = type;
/* Use the default record version, if it is
* set. */
copy_record_version (session, htype, &headers[1]);
header_size = RECORD_HEADER_SIZE(session);
/* Adjust header length and add sequence for DTLS */
if (IS_DTLS(session))
memcpy(&headers[3], &record_state->sequence_number.i, 8);
_gnutls_record_log
("REC[%p]: Preparing Packet %s(%d) with length: %d and target length: %d\n", session,
_gnutls_packet2str (type), type, (int) data_size, (int) target_length);
_mbuffer_set_udata_size(bufel, cipher_size);
_mbuffer_set_uhead_size(bufel, header_size);
ret =
_gnutls_encrypt (session,
data, send_data_size, target_length,
bufel, type, record_params);
if (ret <= 0)
{
gnutls_assert ();
if (ret == 0)
ret = GNUTLS_E_ENCRYPTION_FAILED;
gnutls_free (bufel);
return ret; /* error */
}
cipher_size = _mbuffer_get_udata_size(bufel);
retval = send_data_size;
session->internals.record_send_buffer_user_size = send_data_size;
/* increase sequence number
*/
if (sequence_increment (session, &record_state->sequence_number) != 0)
{
session_invalidate (session);
gnutls_free (bufel);
return gnutls_assert_val(GNUTLS_E_RECORD_LIMIT_REACHED);
}
ret = _gnutls_io_write_buffered (session, bufel, mflags);
}
if (ret != cipher_size)
{
/* If we have sent any data then just return
* the error value. Do not invalidate the session.
*/
if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
return gnutls_assert_val(ret);
if (ret > 0)
ret = gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
session_unresumable (session);
session->internals.may_not_write = 1;
return gnutls_assert_val(ret);
}
session->internals.record_send_buffer_user_size = 0;
_gnutls_record_log ("REC[%p]: Sent Packet[%d] %s(%d) in epoch %d and length: %d\n",
session,
(unsigned int)
_gnutls_uint64touint32
(&record_state->sequence_number),
_gnutls_packet2str (type), type,
(int) record_params->epoch,
(int) cipher_size);
return retval;
}