/*
* @ms: a pointer to the number of milliseconds to wait for data. Use zero or NULL for indefinite.
*
* This function is like recv(with MSG_PEEK). But it does not return -1 on error.
* It does return gnutls_errno instead.
* This function reads data from the socket and keeps them in a buffer, of up to
* max_record_recv_size.
*
* This is not a general purpose function. It returns EXACTLY the data requested,
* which are stored in a local (in the session) buffer.
*
* If the @ms parameter is non zero then this function will return before
* the given amount of milliseconds or return GNUTLS_E_TIMEDOUT.
*
*/
ssize_t
_gnutls_io_read_buffered(gnutls_session_t session, size_t total,
content_type_t recv_type, unsigned int *ms)
{
ssize_t ret;
size_t min;
mbuffer_st *bufel = NULL;
size_t recvdata, readsize;
if (total > max_record_recv_size(session) || total == 0) {
gnutls_assert();
return GNUTLS_E_RECORD_OVERFLOW;
}
/* calculate the actual size, ie. get the minimum of the
* buffered data and the requested data.
*/
min =
MIN(session->internals.record_recv_buffer.byte_length, total);
if (min > 0) {
/* if we have enough buffered data
* then just return them.
*/
if (min == total) {
return min;
}
}
/* min is over zero. recvdata is the data we must
* receive in order to return the requested data.
*/
recvdata = total - min;
readsize = recvdata;
/* Check if the previously read data plus the new data to
* receive are longer than the maximum receive buffer size.
*/
if ((session->internals.record_recv_buffer.byte_length +
recvdata) > max_record_recv_size(session)) {
gnutls_assert(); /* internal error */
return GNUTLS_E_INVALID_REQUEST;
}
/* READ DATA
*/
if (readsize > 0) {
ret =
_gnutls_read(session, &bufel, readsize,
session->internals.pull_func, ms);
/* return immediately if we got an interrupt or eagain
* error.
*/
if (ret < 0) {
return gnutls_assert_val(ret);
}
if (ret == 0) /* EOF */
return gnutls_assert_val(0);
/* copy fresh data to our buffer.
*/
_gnutls_read_log
("RB: Have %d bytes into buffer. Adding %d bytes.\n",
(int) session->internals.record_recv_buffer.
byte_length, (int) ret);
_gnutls_read_log("RB: Requested %d bytes\n", (int) total);
_mbuffer_enqueue(&session->internals.record_recv_buffer,
bufel);
if (IS_DTLS(session))
ret =
MIN(total,
session->internals.record_recv_buffer.
byte_length);
else
ret =
session->internals.record_recv_buffer.
byte_length;
if ((ret > 0) && ((size_t) ret < total)) /* Short Read */
return gnutls_assert_val(GNUTLS_E_AGAIN);
else
return ret;
} else
return gnutls_assert_val(0);
}
static ssize_t
_gnutls_dgram_read(gnutls_session_t session, mbuffer_st ** bufel,
gnutls_pull_func pull_func, unsigned int *ms)
{
ssize_t i, ret;
uint8_t *ptr;
struct timespec t1, t2;
size_t max_size, recv_size;
gnutls_transport_ptr_t fd = session->internals.transport_recv_ptr;
unsigned int diff;
max_size = max_record_recv_size(session);
recv_size = max_size;
session->internals.direction = 0;
if (ms && *ms > 0) {
ret = _gnutls_io_check_recv(session, *ms);
if (ret < 0)
return gnutls_assert_val(ret);
gnutls_gettime(&t1);
}
*bufel = _mbuffer_alloc_align16(max_size, get_total_headers(session));
if (*bufel == NULL)
return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);
ptr = (*bufel)->msg.data;
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\n",
(int) i, fd, err);
ret = errno_to_gerr(err, 1);
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.
* That assumption may not work on DCCP. */
gnutls_assert();
ret = 0;
goto cleanup;
}
_mbuffer_set_udata_size(*bufel, i);
}
if (ms && *ms > 0) {
gnutls_gettime(&t2);
diff = timespec_sub_ms(&t2, &t1);
if (diff < *ms)
*ms -= diff;
else {
ret = gnutls_assert_val(GNUTLS_E_TIMEDOUT);
goto cleanup;
}
}
_gnutls_read_log("READ: read %d bytes from %p\n", (int) i, fd);
return i;
cleanup:
_mbuffer_xfree(bufel);
return ret;
}
static ssize_t
_gnutls_stream_read(gnutls_session_t session, mbuffer_st ** bufel,
size_t size, gnutls_pull_func pull_func,
unsigned int *ms)
{
size_t left;
ssize_t i = 0;
size_t max_size = max_record_recv_size(session);
uint8_t *ptr;
gnutls_transport_ptr_t fd = session->internals.transport_recv_ptr;
int ret;
struct timespec t1, t2;
unsigned int diff;
session->internals.direction = 0;
*bufel = _mbuffer_alloc_align16(MAX(max_size, size), get_total_headers(session));
if (!*bufel) {
gnutls_assert();
return GNUTLS_E_MEMORY_ERROR;
}
ptr = (*bufel)->msg.data;
left = size;
while (left > 0) {
if (ms && *ms > 0) {
ret = _gnutls_io_check_recv(session, *ms);
if (ret < 0) {
gnutls_assert();
goto cleanup;
}
gnutls_gettime(&t1);
}
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;
}
ret = errno_to_gerr(err, 0);
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)
break; /* EOF */
}
left -= i;
(*bufel)->msg.size += i;
if (ms && *ms > 0 && *ms != GNUTLS_INDEFINITE_TIMEOUT) {
gnutls_gettime(&t2);
diff = timespec_sub_ms(&t2, &t1);
if (diff < *ms)
*ms -= diff;
else {
ret = gnutls_assert_val(GNUTLS_E_TIMEDOUT);
goto cleanup;
}
}
}
finish:
_gnutls_read_log("READ: read %d bytes from %p\n",
(int) (size - left), fd);
if (size - left == 0)
_mbuffer_xfree(bufel);
return (size - left);
cleanup:
_mbuffer_xfree(bufel);
return ret;
}
static int recv_headers(gnutls_session_t session,
record_parameters_st *record_params,
content_type_t type,
gnutls_handshake_description_t htype,
struct tls_record_st *record, unsigned int *ms)
{
int ret;
gnutls_datum_t raw; /* raw headers */
/* Read the headers.
*/
record->header_size = record->packet_size =
RECORD_HEADER_SIZE(session);
ret =
_gnutls_io_read_buffered(session, record->header_size, -1, ms);
if (ret != record->header_size) {
if (ret < 0 && gnutls_error_is_fatal(ret) == 0)
return ret;
if (ret > 0)
ret = GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
else if (ret == 0)
ret = GNUTLS_E_PREMATURE_TERMINATION;
return gnutls_assert_val(ret);
}
ret = _mbuffer_linearize_align16(&session->internals.record_recv_buffer,
get_total_headers2(session, record_params));
if (ret < 0)
return gnutls_assert_val(ret);
_mbuffer_head_get_first(&session->internals.record_recv_buffer,
&raw);
if (raw.size < RECORD_HEADER_SIZE(session))
return
gnutls_assert_val(GNUTLS_E_UNEXPECTED_PACKET_LENGTH);
record_read_headers(session, raw.data, type, htype, record);
/* Check if the DTLS epoch is valid */
if (IS_DTLS(session)) {
if (_gnutls_epoch_is_valid(session, record->epoch) == 0) {
_gnutls_audit_log(session,
"Discarded message[%u] with invalid epoch %u.\n",
(unsigned int)
_gnutls_uint64touint32(&record->
sequence),
(unsigned int) record->sequence.
i[0] * 256 +
(unsigned int) record->sequence.
i[1]);
gnutls_assert();
/* doesn't matter, just a fatal error */
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
}
/* Here we check if the Type of the received packet is
* ok.
*/
if ((ret = check_recv_type(session, record->type)) < 0)
return gnutls_assert_val(ret);
/* Here we check if the advertized version is the one we
* negotiated in the handshake.
*/
if ((ret =
record_check_version(session, htype, record->version)) < 0)
return gnutls_assert_val(ret);
if (record->length > max_record_recv_size(session)) {
_gnutls_audit_log
(session, "Received packet with illegal length: %u\n",
(unsigned int) record->length);
return
gnutls_assert_val(GNUTLS_E_UNEXPECTED_PACKET_LENGTH);
}
_gnutls_record_log
("REC[%p]: Expected Packet %s(%d)\n", session,
_gnutls_packet2str(type), type);
_gnutls_record_log
("REC[%p]: Received Packet %s(%d) with length: %d\n", session,
_gnutls_packet2str(record->type), record->type,
record->length);
return 0;
}
