int _mbuffer_linearize(mbuffer_head_st * buf)
{
mbuffer_st *bufel, *cur;
gnutls_datum_t msg;
size_t pos = 0;
if (buf->length <= 1) {
/* Nothing to do */
return 0;
}
bufel = _mbuffer_alloc(buf->byte_length);
if (!bufel) {
gnutls_assert();
return GNUTLS_E_MEMORY_ERROR;
}
for (cur = _mbuffer_head_get_first(buf, &msg);
msg.data != NULL; cur = _mbuffer_head_get_next(cur, &msg)) {
memcpy(&bufel->msg.data[pos], msg.data, msg.size);
bufel->msg.size += msg.size;
pos += msg.size;
}
_mbuffer_head_clear(buf);
_mbuffer_enqueue(buf, bufel);
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.
*
* @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;
}
/* @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.
*
* 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;
}
static ssize_t
_gnutls_stream_read (gnutls_session_t session, mbuffer_st **bufel,
size_t size, gnutls_pull_func pull_func)
{
size_t left;
ssize_t i = 0;
size_t max_size = _gnutls_get_max_decrypted_data(session);
char *ptr;
gnutls_transport_ptr_t fd = session->internals.transport_recv_ptr;
*bufel = _mbuffer_alloc (0, MAX(max_size, size));
if (!*bufel)
{
gnutls_assert ();
return GNUTLS_E_MEMORY_ERROR;
}
ptr = (*bufel)->msg.data;
session->internals.direction = 0;
left = size;
while (left > 0)
{
reset_errno (session);
i = pull_func (fd, &ptr[size - left], left);
if (i < 0)
{
int err = get_errno (session);
_gnutls_read_log ("READ: %d returned from %p, errno=%d gerrno=%d\n",
(int) i, fd, errno, session->internals.errnum);
if (err == EAGAIN || err == EINTR)
{
if (size - left > 0)
{
_gnutls_read_log ("READ: returning %d bytes from %p\n",
(int) (size - left), fd);
goto finish;
}
if (err == EAGAIN)
return GNUTLS_E_AGAIN;
return GNUTLS_E_INTERRUPTED;
}
else
{
gnutls_assert ();
return GNUTLS_E_PULL_ERROR;
}
}
else
{
_gnutls_read_log ("READ: Got %d bytes from %p\n", (int) i, fd);
if (i == 0)
break; /* EOF */
}
left -= i;
(*bufel)->msg.size += i;
}
finish:
_gnutls_read_log ("READ: read %d bytes from %p\n",
(int) (size - left), fd);
return (size - left);
}
static ssize_t
_gnutls_dgram_read (gnutls_session_t session, mbuffer_st **bufel,
gnutls_pull_func pull_func)
{
ssize_t i, ret;
char *ptr;
size_t max_size = _gnutls_get_max_decrypted_data(session);
size_t recv_size = MAX_RECV_SIZE(session);
gnutls_transport_ptr_t fd = session->internals.transport_recv_ptr;
if (recv_size > max_size)
recv_size = max_size;
*bufel = _mbuffer_alloc (0, max_size);
if (*bufel == NULL)
return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
ptr = (*bufel)->msg.data;
session->internals.direction = 0;
reset_errno (session);
i = pull_func (fd, ptr, recv_size);
if (i < 0)
{
int err = get_errno (session);
_gnutls_read_log ("READ: %d returned from %p, errno=%d gerrno=%d\n",
(int) i, fd, errno, session->internals.errnum);
if (err == EAGAIN)
{
ret = GNUTLS_E_AGAIN;
goto cleanup;
}
else if (err == EINTR)
{
ret = GNUTLS_E_INTERRUPTED;
goto cleanup;
}
else
{
gnutls_assert ();
ret = GNUTLS_E_PULL_ERROR;
goto cleanup;
}
}
else
{
_gnutls_read_log ("READ: Got %d bytes from %p\n", (int) i, fd);
if (i == 0)
{
/* If we get here, we likely have a stream socket.
* FIXME: this probably breaks DCCP. */
gnutls_assert ();
ret = 0;
goto cleanup;
}
_mbuffer_set_udata_size (*bufel, i);
}
_gnutls_read_log ("READ: read %d bytes from %p\n", (int) i, fd);
return i;
cleanup:
_mbuffer_xfree(bufel);
return ret;
}