lib/mbedtls
1
0
Fork 0
mirror of https://github.com/Mbed-TLS/mbedtls.git synced 2025-07-29 11:41:15 +03:00
Code Activity

Merge branch 'development' into dtls

Browse Source 
* development:
  Add missing guards for gnuTLS
  Prepare for mbed TLS 1.3.10 release
  Fix potential timing issue in RSA pms handling

Conflicts:
	ChangeLog
	doxygen/input/doc_mainpage.h
	doxygen/mbedtls.doxyfile
	include/polarssl/version.h
	library/CMakeLists.txt
	library/ssl_srv.c
	tests/suites/test_suite_version.data
	visualc/VS2010/mbedTLS.vcxproj
	visualc/VS6/mbedtls.dsp
	visualc/VS6/mbedtls.dsw
This commit is contained in:
Manuel Pégourié-Gonnard
2015-02-09 11:42:40 +00:00
parent 4eaf8f02bb 539d972a25
commit f7d2bbaa62
54 changed files with 795 additions and 2304 deletions
Download Patch File Download Diff File Expand all files Collapse all files

55
library/ssl_srv.c
View File

@ -3218,6 +3218,10 @@ static int ssl_parse_encrypted_pms( ssl_context *ssl,
size_t len = pk_get_len( ssl_own_key( ssl ) );
unsigned char *pms = ssl->handshake->premaster + pms_offset;
unsigned char ver[2];
unsigned char fake_pms[48], peer_pms[48];
unsigned char mask;
unsigned int uret;
size_t i;
if( ! pk_can_do( ssl_own_key( ssl ), POLARSSL_PK_RSA ) )
{
@ -3250,32 +3254,47 @@ static int ssl_parse_encrypted_pms( ssl_context *ssl,
ssl_write_version( ssl->handshake->max_major_ver,
ssl->handshake->max_minor_ver,
ssl->transport, ver );
/*
* Protection against Bleichenbacher's attack: invalid PKCS#1 v1.5 padding
* must not cause the connection to end immediately; instead, send a
* bad_record_mac later in the handshake.
* Also, avoid data-dependant branches here to protect against
* timing-based variants.
*/
ret = ssl->f_rng( ssl->p_rng, fake_pms, sizeof( fake_pms ) );
if( ret != 0 )
return( ret );
ret = pk_decrypt( ssl_own_key( ssl ), p, len,
pms, &ssl->handshake->pmslen,
sizeof( ssl->handshake->premaster ) - pms_offset,
peer_pms, &ssl->handshake->pmslen,
sizeof( peer_pms ),
ssl->f_rng, ssl->p_rng );
if( ret != 0 || ssl->handshake->pmslen != 48 ||
pms[0] != ver[0] ||
pms[1] != ver[1] )
{
ret |= ssl->handshake->pmslen - 48;
ret |= peer_pms[0] - ver[0];
ret |= peer_pms[1] - ver[1];
#if defined(POLARSSL_SSL_DEBUG_ALL)
if( ret != 0 )
SSL_DEBUG_MSG( 1, ( "bad client key exchange message" ) );
#endif
/*
* Protection against Bleichenbacher's attack:
* invalid PKCS#1 v1.5 padding must not cause
* the connection to end immediately; instead,
* send a bad_record_mac later in the handshake.
*/
ssl->handshake->pmslen = 48;
ret = ssl->f_rng( ssl->p_rng, pms, ssl->handshake->pmslen );
if( ret != 0 )
return( ret );
if( sizeof( ssl->handshake->premaster ) < pms_offset ||
sizeof( ssl->handshake->premaster ) - pms_offset < 48 )
{
SSL_DEBUG_MSG( 1, ( "should never happen" ) );
return( POLARSSL_ERR_SSL_INTERNAL_ERROR );
}
ssl->handshake->pmslen = 48;
return( ret );
uret = (unsigned) ret;
uret |= -uret; /* msb = ( ret != 0 ) */
uret >>= 8 * sizeof( uret ) - 1; /* uret = ( ret != 0 ) */
mask = (unsigned char)( -uret ) ; /* ret ? 0xff : 0x00 */
for( i = 0; i < ssl->handshake->pmslen; i++ )
pms[i] = ( mask & fake_pms[i] ) | ( (~mask) & peer_pms[i] );
return( 0 );
}
#endif /* POLARSSL_KEY_EXCHANGE_RSA_ENABLED ||
POLARSSL_KEY_EXCHANGE_RSA_PSK_ENABLED */