Fix earlier incomplete change in RSA PMS reading

Probably a bad merge from the 1.3 branch
parent 19389753
......@@ -2959,7 +2959,8 @@ static int ssl_parse_encrypted_pms( mbedtls_ssl_context *ssl,
unsigned char ver[2];
unsigned char fake_pms[48], peer_pms[48];
unsigned char mask;
size_t i, diff, peer_pmslen;
size_t i, peer_pmslen;
unsigned int diff;
if( ! mbedtls_pk_can_do( mbedtls_ssl_own_key( ssl ), MBEDTLS_PK_RSA ) )
{
......@@ -2992,6 +2993,7 @@ static int ssl_parse_encrypted_pms( mbedtls_ssl_context *ssl,
mbedtls_ssl_write_version( ssl->handshake->max_major_ver,
ssl->handshake->max_minor_ver,
ssl->conf->transport, ver );
/*
* Protection against Bleichenbacher's attack: invalid PKCS#1 v1.5 padding
* must not cause the connection to end immediately; instead, send a
......@@ -3008,10 +3010,10 @@ static int ssl_parse_encrypted_pms( mbedtls_ssl_context *ssl,
sizeof( peer_pms ),
ssl->conf->f_rng, ssl->conf->p_rng );
diff = (size_t) ret;
diff = (unsigned int) ret;
diff |= peer_pmslen ^ 48;
diff |= peer_pms[0] ^ ssl->handshake->max_major_ver;
diff |= peer_pms[1] ^ ssl->handshake->max_minor_ver;
diff |= peer_pms[0] ^ ver[0];
diff |= peer_pms[1] ^ ver[1];
#if defined(MBEDTLS_SSL_DEBUG_ALL)
if( diff != 0 )
......@@ -3026,8 +3028,8 @@ static int ssl_parse_encrypted_pms( mbedtls_ssl_context *ssl,
}
ssl->handshake->pmslen = 48;
mask = ( diff | - diff ) >> ( sizeof( size_t ) * 8 - 1 );
mask = (unsigned char)( - ( ret != 0 ) ); /* mask = diff ? 0xff : 0x00 */
/* mask = diff ? 0xff : 0x00 */
mask = - ( ( diff | - diff ) >> ( sizeof( unsigned int ) * 8 - 1 ) );
for( i = 0; i < ssl->handshake->pmslen; i++ )
pms[i] = ( mask & fake_pms[i] ) | ( (~mask) & peer_pms[i] );
......
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