/* This function is only used with berkeley style sockets.
* Clears the peeked data (read with MSG_PEEK).
*/
int
_gnutls_io_clear_peeked_data (gnutls_session_t session)
{
char *peekdata;
int ret, sum;
if (session->internals.have_peeked_data == 0 || RCVLOWAT == 0)
return 0;
peekdata = gnutls_alloca (RCVLOWAT);
if (peekdata == NULL)
{
gnutls_assert ();
return GNUTLS_E_MEMORY_ERROR;
}
/* this was already read by using MSG_PEEK - so it shouldn't fail */
sum = 0;
do
{ /* we need this to finish now */
ret = _gnutls_read (session, peekdata, RCVLOWAT - sum, 0);
if (ret > 0)
sum += ret;
}
while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN
|| sum < RCVLOWAT);
gnutls_afree (peekdata);
if (ret < 0)
{
gnutls_assert ();
return ret;
}
session->internals.have_peeked_data = 0;
return 0;
}
/*
* @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);
}
/* 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_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. A pointer (iptr) to this buffer is returned.
*
*/
ssize_t
_gnutls_io_read_buffered (gnutls_session_t session, opaque ** iptr,
size_t sizeOfPtr, content_type_t recv_type)
{
ssize_t ret = 0, ret2 = 0;
size_t min;
int buf_pos;
opaque *buf;
int recvlowat;
int recvdata, alloc_size;
*iptr = session->internals.record_recv_buffer.data;
if (sizeOfPtr > MAX_RECV_SIZE || sizeOfPtr == 0)
{
gnutls_assert (); /* internal error */
return GNUTLS_E_INVALID_REQUEST;
}
/* If an external pull function is used, then do not leave
* any data into the kernel buffer.
*/
if (session->internals._gnutls_pull_func != NULL)
{
recvlowat = 0;
}
else
{
/* leave peeked data to the kernel space only if application data
* is received and we don't have any peeked
* data in gnutls session.
*/
if (recv_type != GNUTLS_APPLICATION_DATA
&& session->internals.have_peeked_data == 0)
recvlowat = 0;
else
recvlowat = RCVLOWAT;
}
/* calculate the actual size, ie. get the minimum of the
* buffered data and the requested data.
*/
min = MIN (session->internals.record_recv_buffer.length, sizeOfPtr);
if (min > 0)
{
/* if we have enough buffered data
* then just return them.
*/
if (min == sizeOfPtr)
{
return min;
}
}
/* min is over zero. recvdata is the data we must
* receive in order to return the requested data.
*/
recvdata = sizeOfPtr - min;
/* 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.length + recvdata) >
MAX_RECV_SIZE)
{
gnutls_assert (); /* internal error */
return GNUTLS_E_INVALID_REQUEST;
}
/* Allocate the data required to store the new packet.
*/
alloc_size = recvdata + session->internals.record_recv_buffer.length;
session->internals.record_recv_buffer.data =
gnutls_realloc_fast (session->internals.record_recv_buffer.data,
alloc_size);
if (session->internals.record_recv_buffer.data == NULL)
{
gnutls_assert ();
return GNUTLS_E_MEMORY_ERROR;
}
buf_pos = session->internals.record_recv_buffer.length;
buf = session->internals.record_recv_buffer.data;
*iptr = buf;
/* READ DATA - but leave RCVLOWAT bytes in the kernel buffer.
*/
if (recvdata - recvlowat > 0)
{
ret = _gnutls_read (session, &buf[buf_pos], recvdata - recvlowat, 0);
/* return immediately if we got an interrupt or eagain
* error.
*/
if (ret < 0 && gnutls_error_is_fatal (ret) == 0)
{
return ret;
}
}
/* copy fresh data to our buffer.
*/
if (ret > 0)
{
_gnutls_read_log
("RB: Have %d bytes into buffer. Adding %d bytes.\n",
session->internals.record_recv_buffer.length, ret);
_gnutls_read_log ("RB: Requested %d bytes\n", sizeOfPtr);
session->internals.record_recv_buffer.length += ret;
}
buf_pos = session->internals.record_recv_buffer.length;
/* This is hack in order for select to work. Just leave recvlowat data,
* into the kernel buffer (using a read with MSG_PEEK), thus making
* select think, that the socket is ready for reading.
* MSG_PEEK is only used with berkeley style sockets.
*/
if (ret == (recvdata - recvlowat) && recvlowat > 0)
{
ret2 = _gnutls_read (session, &buf[buf_pos], recvlowat, MSG_PEEK);
if (ret2 < 0 && gnutls_error_is_fatal (ret2) == 0)
{
return ret2;
}
if (ret2 > 0)
{
_gnutls_read_log ("RB-PEEK: Read %d bytes in PEEK MODE.\n", ret2);
_gnutls_read_log
("RB-PEEK: Have %d bytes into buffer. Adding %d bytes.\nRB: Requested %d bytes\n",
session->internals.record_recv_buffer.length, ret2, sizeOfPtr);
session->internals.have_peeked_data = 1;
session->internals.record_recv_buffer.length += ret2;
}
}
if (ret < 0 || ret2 < 0)
{
gnutls_assert ();
/* that's because they are initialized to 0 */
return MIN (ret, ret2);
}
ret += ret2;
if (ret > 0 && ret < recvlowat)
{
gnutls_assert ();
return GNUTLS_E_AGAIN;
}
if (ret == 0)
{ /* EOF */
gnutls_assert ();
return 0;
}
ret = session->internals.record_recv_buffer.length;
if ((ret > 0) && ((size_t) ret < sizeOfPtr))
{
/* Short Read */
gnutls_assert ();
return GNUTLS_E_AGAIN;
}
else
{
return ret;
}
}
