mbedtls/programs/ssl/ssl_test_common_source.c
Gilles Peskine 6d576c9646 Call setbuf when reading or writing files: programs
After opening a file containing sensitive data, call mbedtls_setbuf() to
disable buffering. This way, we don't expose sensitive data to a memory
disclosure vulnerability in a buffer outside our control.

This commit adds a call to mbedtls_setbuf() after each call to fopen(),
but only in sample programs that were calling mbedtls_platform_zeroize().
Don't bother protecting stdio buffers in programs where application buffers
weren't protected.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2022-06-30 17:06:11 +02:00

336 lines
11 KiB
C

/*
* Common source code for SSL test programs. This file is included by
* both ssl_client2.c and ssl_server2.c and is intended for source
* code that is textually identical in both programs, but that cannot be
* compiled separately because it refers to types or macros that are
* different in the two programs, or because it would have an incomplete
* type.
*
* This file is meant to be #include'd and cannot be compiled separately.
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
void eap_tls_key_derivation( void *p_expkey,
mbedtls_ssl_key_export_type secret_type,
const unsigned char *secret,
size_t secret_len,
const unsigned char client_random[32],
const unsigned char server_random[32],
mbedtls_tls_prf_types tls_prf_type )
{
eap_tls_keys *keys = (eap_tls_keys *)p_expkey;
/* We're only interested in the TLS 1.2 master secret */
if( secret_type != MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET )
return;
if( secret_len != sizeof( keys->master_secret ) )
return;
memcpy( keys->master_secret, secret, sizeof( keys->master_secret ) );
memcpy( keys->randbytes, client_random, 32 );
memcpy( keys->randbytes + 32, server_random, 32 );
keys->tls_prf_type = tls_prf_type;
}
void nss_keylog_export( void *p_expkey,
mbedtls_ssl_key_export_type secret_type,
const unsigned char *secret,
size_t secret_len,
const unsigned char client_random[32],
const unsigned char server_random[32],
mbedtls_tls_prf_types tls_prf_type )
{
char nss_keylog_line[ 200 ];
size_t const client_random_len = 32;
size_t len = 0;
size_t j;
/* We're only interested in the TLS 1.2 master secret */
if( secret_type != MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET )
return;
((void) p_expkey);
((void) server_random);
((void) tls_prf_type);
len += sprintf( nss_keylog_line + len,
"%s", "CLIENT_RANDOM " );
for( j = 0; j < client_random_len; j++ )
{
len += sprintf( nss_keylog_line + len,
"%02x", client_random[j] );
}
len += sprintf( nss_keylog_line + len, " " );
for( j = 0; j < secret_len; j++ )
{
len += sprintf( nss_keylog_line + len,
"%02x", secret[j] );
}
len += sprintf( nss_keylog_line + len, "\n" );
nss_keylog_line[ len ] = '\0';
mbedtls_printf( "\n" );
mbedtls_printf( "---------------- NSS KEYLOG -----------------\n" );
mbedtls_printf( "%s", nss_keylog_line );
mbedtls_printf( "---------------------------------------------\n" );
if( opt.nss_keylog_file != NULL )
{
FILE *f;
if( ( f = fopen( opt.nss_keylog_file, "a" ) ) == NULL )
{
goto exit;
}
/* Ensure no stdio buffering of secrets, as such buffers cannot be
* wiped. */
mbedtls_setbuf( f, NULL );
if( fwrite( nss_keylog_line, 1, len, f ) != len )
{
fclose( f );
goto exit;
}
fclose( f );
}
exit:
mbedtls_platform_zeroize( nss_keylog_line,
sizeof( nss_keylog_line ) );
}
#if defined( MBEDTLS_SSL_DTLS_SRTP )
void dtls_srtp_key_derivation( void *p_expkey,
mbedtls_ssl_key_export_type secret_type,
const unsigned char *secret,
size_t secret_len,
const unsigned char client_random[32],
const unsigned char server_random[32],
mbedtls_tls_prf_types tls_prf_type )
{
dtls_srtp_keys *keys = (dtls_srtp_keys *)p_expkey;
/* We're only interested in the TLS 1.2 master secret */
if( secret_type != MBEDTLS_SSL_KEY_EXPORT_TLS12_MASTER_SECRET )
return;
if( secret_len != sizeof( keys->master_secret ) )
return;
memcpy( keys->master_secret, secret, sizeof( keys->master_secret ) );
memcpy( keys->randbytes, client_random, 32 );
memcpy( keys->randbytes + 32, server_random, 32 );
keys->tls_prf_type = tls_prf_type;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */
int ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char const *buf, size_t len )
{
int my_ret = 0, ret_cr1, ret_cr2;
unsigned char *tmp_buf;
/* Record checking may modify the input buffer,
* so make a copy. */
tmp_buf = mbedtls_calloc( 1, len );
if( tmp_buf == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( tmp_buf, buf, len );
ret_cr1 = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret_cr1 != MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE )
{
/* Test-only: Make sure that mbedtls_ssl_check_record()
* doesn't alter state. */
memcpy( tmp_buf, buf, len ); /* Restore buffer */
ret_cr2 = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret_cr2 != ret_cr1 )
{
mbedtls_printf( "mbedtls_ssl_check_record() returned inconsistent results.\n" );
my_ret = -1;
goto cleanup;
}
switch( ret_cr1 )
{
case 0:
break;
case MBEDTLS_ERR_SSL_INVALID_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected invalid record.\n" );
break;
case MBEDTLS_ERR_SSL_INVALID_MAC:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unauthentic record.\n" );
break;
case MBEDTLS_ERR_SSL_UNEXPECTED_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unexpected record.\n" );
break;
default:
mbedtls_printf( "mbedtls_ssl_check_record() failed fatally with -%#04x.\n", (unsigned int) -ret_cr1 );
my_ret = -1;
goto cleanup;
}
/* Regardless of the outcome, forward the record to the stack. */
}
cleanup:
mbedtls_free( tmp_buf );
return( my_ret );
}
int recv_cb( void *ctx, unsigned char *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
size_t recv_len;
int ret;
if( opt.nbio == 2 )
ret = delayed_recv( io_ctx->net, buf, len );
else
ret = mbedtls_net_recv( io_ctx->net, buf, len );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
}
return( (int) recv_len );
}
int recv_timeout_cb( void *ctx, unsigned char *buf, size_t len,
uint32_t timeout )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
int ret;
size_t recv_len;
ret = mbedtls_net_recv_timeout( io_ctx->net, buf, len, timeout );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
}
return( (int) recv_len );
}
int send_cb( void *ctx, unsigned char const *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
if( opt.nbio == 2 )
return( delayed_send( io_ctx->net, buf, len ) );
return( mbedtls_net_send( io_ctx->net, buf, len ) );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_RSA_C)
#define MBEDTLS_SSL_SIG_ALG( hash ) (( hash << 8 ) | MBEDTLS_SSL_SIG_ECDSA), \
(( hash << 8 ) | MBEDTLS_SSL_SIG_RSA),
#elif defined(MBEDTLS_ECDSA_C)
#define MBEDTLS_SSL_SIG_ALG( hash ) (( hash << 8 ) | MBEDTLS_SSL_SIG_ECDSA),
#elif defined(MBEDTLS_RSA_C)
#define MBEDTLS_SSL_SIG_ALG( hash ) (( hash << 8 ) | MBEDTLS_SSL_SIG_RSA),
#else
#define MBEDTLS_SSL_SIG_ALG( hash )
#endif
uint16_t ssl_sig_algs_for_test[] = {
#if defined(MBEDTLS_SHA512_C)
MBEDTLS_SSL_SIG_ALG( MBEDTLS_SSL_HASH_SHA512 )
#endif
#if defined(MBEDTLS_SHA384_C)
MBEDTLS_SSL_SIG_ALG( MBEDTLS_SSL_HASH_SHA384 )
#endif
#if defined(MBEDTLS_SHA256_C)
MBEDTLS_SSL_SIG_ALG( MBEDTLS_SSL_HASH_SHA256 )
#endif
#if defined(MBEDTLS_SHA224_C)
MBEDTLS_SSL_SIG_ALG( MBEDTLS_SSL_HASH_SHA224 )
#endif
#if defined(MBEDTLS_SHA1_C)
/* Allow SHA-1 as we use it extensively in tests. */
MBEDTLS_SSL_SIG_ALG( MBEDTLS_SSL_HASH_SHA1 )
#endif
MBEDTLS_TLS1_3_SIG_NONE
};
#endif /* MBEDTLS_X509_CRT_PARSE_C */
#if defined(MBEDTLS_X509_CRT_PARSE_C)
/** Functionally equivalent to mbedtls_x509_crt_verify_info, see that function
* for more info.
*/
int x509_crt_verify_info( char *buf, size_t size, const char *prefix,
uint32_t flags )
{
#if !defined(MBEDTLS_X509_REMOVE_INFO)
return( mbedtls_x509_crt_verify_info( buf, size, prefix, flags ) );
#else /* !MBEDTLS_X509_REMOVE_INFO */
int ret;
char *p = buf;
size_t n = size;
#define X509_CRT_ERROR_INFO( err, err_str, info ) \
if( ( flags & err ) != 0 ) \
{ \
ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, info ); \
MBEDTLS_X509_SAFE_SNPRINTF; \
flags ^= err; \
}
MBEDTLS_X509_CRT_ERROR_INFO_LIST
#undef X509_CRT_ERROR_INFO
if( flags != 0 )
{
ret = mbedtls_snprintf( p, n, "%sUnknown reason "
"(this should not happen)\n", prefix );
MBEDTLS_X509_SAFE_SNPRINTF;
}
return( (int) ( size - n ) );
#endif /* MBEDTLS_X509_REMOVE_INFO */
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */