Merge remote-tracking branch 'public/pr/1768' into mbedtls-2.7

This commit is contained in:
Simon Butcher 2018-06-27 11:09:27 +01:00
commit 035d824ad5
3 changed files with 36 additions and 10 deletions

View file

@ -7,6 +7,8 @@ Bugfix
Contributed by fbrosson in #1533.
* Fix a memory leak in mbedtls_x509_csr_parse(), found by catenacyber,
Philippe Antoine.
* Clarify documentation for mbedtls_ssl_write() to include 0 as a valid
return value. Found by @davidwu2000. #839
= mbed TLS 2.7.4 branch released 2018-06-18

View file

@ -2504,17 +2504,19 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len )
* or MBEDTLS_ERR_SSL_WANT_WRITE or MBEDTLS_ERR_SSL_WANT_READ,
* or another negative error code.
*
* \note If this function returns something other than a positive
* value or MBEDTLS_ERR_SSL_WANT_READ/WRITE, the ssl context
* becomes unusable, and you should either free it or call
* \c mbedtls_ssl_session_reset() on it before re-using it for
* a new connection; the current connection must be closed.
* \note If this function returns something other than 0, a positive
* value or MBEDTLS_ERR_SSL_WANT_READ/WRITE, you must stop
* using the SSL context for reading or writing, and either
* free it or call \c mbedtls_ssl_session_reset() on it before
* re-using it for a new connection; the current connection
* must be closed.
*
* \note When this function returns MBEDTLS_ERR_SSL_WANT_WRITE/READ,
* it must be called later with the *same* arguments,
* until it returns a positive value. When the function returns
* MBEDTLS_ERR_SSL_WANT_WRITE there may be some partial
* data in the output buffer, however this is not yet sent.
* until it returns a value greater that or equal to 0. When
* the function returns MBEDTLS_ERR_SSL_WANT_WRITE there may be
* some partial data in the output buffer, however this is not
* yet sent.
*
* \note If the requested length is greater than the maximum
* fragment length (either the built-in limit or the one set
@ -2523,6 +2525,9 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len )
* - with DTLS, MBEDTLS_ERR_SSL_BAD_INPUT_DATA is returned.
* \c mbedtls_ssl_get_max_frag_len() may be used to query the
* active maximum fragment length.
*
* \note Attempting to write 0 bytes will result in an empty TLS
* application record being sent.
*/
int mbedtls_ssl_write( mbedtls_ssl_context *ssl, const unsigned char *buf, size_t len );

View file

@ -7137,8 +7137,16 @@ int mbedtls_ssl_read( mbedtls_ssl_context *ssl, unsigned char *buf, size_t len )
}
/*
* Send application data to be encrypted by the SSL layer,
* taking care of max fragment length and buffer size
* Send application data to be encrypted by the SSL layer, taking care of max
* fragment length and buffer size.
*
* According to RFC 5246 Section 6.2.1:
*
* Zero-length fragments of Application data MAY be sent as they are
* potentially useful as a traffic analysis countermeasure.
*
* Therefore, it is possible that the input message length is 0 and the
* corresponding return code is 0 on success.
*/
static int ssl_write_real( mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len )
@ -7166,6 +7174,12 @@ static int ssl_write_real( mbedtls_ssl_context *ssl,
if( ssl->out_left != 0 )
{
/*
* The user has previously tried to send the data and
* MBEDTLS_ERR_SSL_WANT_WRITE or the message was only partially
* written. In this case, we expect the high-level write function
* (e.g. mbedtls_ssl_write()) to be called with the same parameters
*/
if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_flush_output", ret );
@ -7174,6 +7188,11 @@ static int ssl_write_real( mbedtls_ssl_context *ssl,
}
else
{
/*
* The user is trying to send a message the first time, so we need to
* copy the data into the internal buffers and setup the data structure
* to keep track of partial writes
*/
ssl->out_msglen = len;
ssl->out_msgtype = MBEDTLS_SSL_MSG_APPLICATION_DATA;
memcpy( ssl->out_msg, buf, len );