Merge remote-tracking branch 'public/pr/1915' into development

This commit is contained in:
Simon Butcher 2018-08-28 11:45:44 +01:00
commit 4613772dea
2 changed files with 25 additions and 3 deletions

View file

@ -21,6 +21,9 @@ Changes
Drozd. Fixes #1215 raised by randombit.
* Improve compatibility with some alternative CCM implementations by using
CCM test vectors from RAM.
* Fix a miscalculation of the maximum record expansion in
mbedtls_ssl_get_record_expansion() in case of ChachaPoly ciphersuites,
or CBC ciphersuites in (D)TLS versions 1.1 or higher. Fixes #1913, #1914.
= mbed TLS 2.12.0 branch released 2018-07-25

View file

@ -6842,8 +6842,9 @@ const char *mbedtls_ssl_get_version( const mbedtls_ssl_context *ssl )
int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl )
{
size_t transform_expansion;
size_t transform_expansion = 0;
const mbedtls_ssl_transform *transform = ssl->transform_out;
unsigned block_size;
if( transform == NULL )
return( (int) mbedtls_ssl_hdr_len( ssl ) );
@ -6857,13 +6858,31 @@ int mbedtls_ssl_get_record_expansion( const mbedtls_ssl_context *ssl )
{
case MBEDTLS_MODE_GCM:
case MBEDTLS_MODE_CCM:
case MBEDTLS_MODE_CHACHAPOLY:
case MBEDTLS_MODE_STREAM:
transform_expansion = transform->minlen;
break;
case MBEDTLS_MODE_CBC:
transform_expansion = transform->maclen
+ mbedtls_cipher_get_block_size( &transform->cipher_ctx_enc );
block_size = mbedtls_cipher_get_block_size(
&transform->cipher_ctx_enc );
/* Expansion due to the addition of the MAC. */
transform_expansion += transform->maclen;
/* Expansion due to the addition of CBC padding;
* Theoretically up to 256 bytes, but we never use
* more than the block size of the underlying cipher. */
transform_expansion += block_size;
/* For TLS 1.1 or higher, an explicit IV is added
* after the record header. */
#if defined(MBEDTLS_SSL_PROTO_TLS1_1) || defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
transform_expansion += block_size;
#endif /* MBEDTLS_SSL_PROTO_TLS1_1 || MBEDTLS_SSL_PROTO_TLS1_2 */
break;
default: