mirror of
https://github.com/Mbed-TLS/mbedtls.git
synced 2024-12-29 00:17:49 +00:00
543d00ef6f
Signed-off-by: Valerio Setti <vsetti@baylibre.com>
384 lines
11 KiB
C
384 lines
11 KiB
C
/*
|
|
* DTLS cookie callbacks implementation
|
|
*
|
|
* 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.
|
|
*/
|
|
/*
|
|
* These session callbacks use a simple chained list
|
|
* to store and retrieve the session information.
|
|
*/
|
|
|
|
#include "common.h"
|
|
|
|
#if defined(MBEDTLS_SSL_COOKIE_C)
|
|
|
|
#include "mbedtls/platform.h"
|
|
|
|
#include "mbedtls/ssl_cookie.h"
|
|
#include "ssl_misc.h"
|
|
#include "mbedtls/error.h"
|
|
#include "mbedtls/platform_util.h"
|
|
#include "mbedtls/constant_time.h"
|
|
|
|
#include "mbedtls/legacy_or_psa.h"
|
|
|
|
#include <string.h>
|
|
|
|
/*
|
|
* If DTLS is in use, then at least one of SHA-256 or SHA-384 is
|
|
* available. Try SHA-256 first as 384 wastes resources
|
|
*/
|
|
#if defined(MBEDTLS_HAS_ALG_SHA_256_VIA_LOWLEVEL_OR_PSA)
|
|
#define COOKIE_MD MBEDTLS_MD_SHA256
|
|
#define COOKIE_MD_OUTLEN 32
|
|
#define COOKIE_HMAC_LEN 28
|
|
#elif defined(MBEDTLS_HAS_ALG_SHA_384_VIA_LOWLEVEL_OR_PSA)
|
|
#define COOKIE_MD MBEDTLS_MD_SHA384
|
|
#define COOKIE_MD_OUTLEN 48
|
|
#define COOKIE_HMAC_LEN 28
|
|
#else
|
|
#error "DTLS hello verify needs SHA-256 or SHA-384"
|
|
#endif
|
|
|
|
/*
|
|
* Cookies are formed of a 4-bytes timestamp (or serial number) and
|
|
* an HMAC of timestamp and client ID.
|
|
*/
|
|
#define COOKIE_LEN ( 4 + COOKIE_HMAC_LEN )
|
|
|
|
void mbedtls_ssl_cookie_init( mbedtls_ssl_cookie_ctx *ctx )
|
|
{
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
ctx->psa_hmac_key = MBEDTLS_SVC_KEY_ID_INIT;
|
|
#else
|
|
mbedtls_md_init( &ctx->hmac_ctx );
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
#if !defined(MBEDTLS_HAVE_TIME)
|
|
ctx->serial = 0;
|
|
#endif
|
|
ctx->timeout = MBEDTLS_SSL_COOKIE_TIMEOUT;
|
|
|
|
#if !defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
mbedtls_mutex_init( &ctx->mutex );
|
|
#endif
|
|
#endif /* !MBEDTLS_USE_PSA_CRYPTO */
|
|
}
|
|
|
|
void mbedtls_ssl_cookie_set_timeout( mbedtls_ssl_cookie_ctx *ctx, unsigned long delay )
|
|
{
|
|
ctx->timeout = delay;
|
|
}
|
|
|
|
void mbedtls_ssl_cookie_free( mbedtls_ssl_cookie_ctx *ctx )
|
|
{
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
psa_destroy_key( ctx->psa_hmac_key );
|
|
#else
|
|
mbedtls_md_free( &ctx->hmac_ctx );
|
|
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
mbedtls_mutex_free( &ctx->mutex );
|
|
#endif
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
|
|
mbedtls_platform_zeroize( ctx, sizeof( mbedtls_ssl_cookie_ctx ) );
|
|
}
|
|
|
|
int mbedtls_ssl_cookie_setup( mbedtls_ssl_cookie_ctx *ctx,
|
|
int (*f_rng)(void *, unsigned char *, size_t),
|
|
void *p_rng )
|
|
{
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
psa_algorithm_t alg;
|
|
|
|
(void)f_rng;
|
|
(void)p_rng;
|
|
|
|
alg = mbedtls_hash_info_psa_from_md( COOKIE_MD );
|
|
if( alg == 0 )
|
|
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
|
|
|
|
ctx->psa_hmac_alg = PSA_ALG_TRUNCATED_MAC( PSA_ALG_HMAC( alg ),
|
|
COOKIE_HMAC_LEN );
|
|
|
|
psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_VERIFY_MESSAGE |
|
|
PSA_KEY_USAGE_SIGN_MESSAGE );
|
|
psa_set_key_algorithm( &attributes, ctx->psa_hmac_alg );
|
|
psa_set_key_type( &attributes, PSA_KEY_TYPE_HMAC );
|
|
psa_set_key_bits( &attributes, PSA_BYTES_TO_BITS( COOKIE_MD_OUTLEN ) );
|
|
|
|
if( ( status = psa_generate_key( &attributes,
|
|
&ctx->psa_hmac_key ) ) != PSA_SUCCESS )
|
|
{
|
|
return psa_ssl_status_to_mbedtls( status );
|
|
}
|
|
#else
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
unsigned char key[COOKIE_MD_OUTLEN];
|
|
|
|
if( ( ret = f_rng( p_rng, key, sizeof( key ) ) ) != 0 )
|
|
return( ret );
|
|
|
|
ret = mbedtls_md_setup( &ctx->hmac_ctx, mbedtls_md_info_from_type( COOKIE_MD ), 1 );
|
|
if( ret != 0 )
|
|
return( ret );
|
|
|
|
ret = mbedtls_md_hmac_starts( &ctx->hmac_ctx, key, sizeof( key ) );
|
|
if( ret != 0 )
|
|
return( ret );
|
|
|
|
mbedtls_platform_zeroize( key, sizeof( key ) );
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
#if !defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
/*
|
|
* Generate the HMAC part of a cookie
|
|
*/
|
|
MBEDTLS_CHECK_RETURN_CRITICAL
|
|
static int ssl_cookie_hmac( mbedtls_md_context_t *hmac_ctx,
|
|
const unsigned char time[4],
|
|
unsigned char **p, unsigned char *end,
|
|
const unsigned char *cli_id, size_t cli_id_len )
|
|
{
|
|
unsigned char hmac_out[COOKIE_MD_OUTLEN];
|
|
|
|
MBEDTLS_SSL_CHK_BUF_PTR( *p, end, COOKIE_HMAC_LEN );
|
|
|
|
if( mbedtls_md_hmac_reset( hmac_ctx ) != 0 ||
|
|
mbedtls_md_hmac_update( hmac_ctx, time, 4 ) != 0 ||
|
|
mbedtls_md_hmac_update( hmac_ctx, cli_id, cli_id_len ) != 0 ||
|
|
mbedtls_md_hmac_finish( hmac_ctx, hmac_out ) != 0 )
|
|
{
|
|
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
|
|
}
|
|
|
|
memcpy( *p, hmac_out, COOKIE_HMAC_LEN );
|
|
*p += COOKIE_HMAC_LEN;
|
|
|
|
return( 0 );
|
|
}
|
|
#endif /* !MBEDTLS_USE_PSA_CRYPTO */
|
|
|
|
/*
|
|
* Generate cookie for DTLS ClientHello verification
|
|
*/
|
|
int mbedtls_ssl_cookie_write( void *p_ctx,
|
|
unsigned char **p, unsigned char *end,
|
|
const unsigned char *cli_id, size_t cli_id_len )
|
|
{
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
psa_mac_operation_t operation = PSA_MAC_OPERATION_INIT;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
size_t sign_mac_length = 0;
|
|
#endif
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
mbedtls_ssl_cookie_ctx *ctx = (mbedtls_ssl_cookie_ctx *) p_ctx;
|
|
unsigned long t;
|
|
|
|
if( ctx == NULL || cli_id == NULL )
|
|
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
|
|
|
|
MBEDTLS_SSL_CHK_BUF_PTR( *p, end, COOKIE_LEN );
|
|
|
|
#if defined(MBEDTLS_HAVE_TIME)
|
|
t = (unsigned long) mbedtls_time( NULL );
|
|
#else
|
|
t = ctx->serial++;
|
|
#endif
|
|
|
|
MBEDTLS_PUT_UINT32_BE(t, *p, 0);
|
|
*p += 4;
|
|
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
status = psa_mac_sign_setup( &operation, ctx->psa_hmac_key,
|
|
ctx->psa_hmac_alg );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_update( &operation, *p - 4, 4 );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_update( &operation, cli_id, cli_id_len );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_sign_finish( &operation, *p, COOKIE_MD_OUTLEN,
|
|
&sign_mac_length );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
*p += COOKIE_HMAC_LEN;
|
|
|
|
ret = 0;
|
|
#else
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
|
|
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_SSL_INTERNAL_ERROR, ret ) );
|
|
#endif
|
|
|
|
ret = ssl_cookie_hmac( &ctx->hmac_ctx, *p - 4,
|
|
p, end, cli_id, cli_id_len );
|
|
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
|
|
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_SSL_INTERNAL_ERROR,
|
|
MBEDTLS_ERR_THREADING_MUTEX_ERROR ) );
|
|
#endif
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
exit:
|
|
status = psa_mac_abort( &operation );
|
|
if( status != PSA_SUCCESS )
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
return( ret );
|
|
}
|
|
|
|
/*
|
|
* Check a cookie
|
|
*/
|
|
int mbedtls_ssl_cookie_check( void *p_ctx,
|
|
const unsigned char *cookie, size_t cookie_len,
|
|
const unsigned char *cli_id, size_t cli_id_len )
|
|
{
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
psa_mac_operation_t operation = PSA_MAC_OPERATION_INIT;
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
#else
|
|
unsigned char ref_hmac[COOKIE_HMAC_LEN];
|
|
unsigned char *p = ref_hmac;
|
|
#endif
|
|
int ret = 0;
|
|
mbedtls_ssl_cookie_ctx *ctx = (mbedtls_ssl_cookie_ctx *) p_ctx;
|
|
unsigned long cur_time, cookie_time;
|
|
|
|
if( ctx == NULL || cli_id == NULL )
|
|
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
|
|
|
|
if( cookie_len != COOKIE_LEN )
|
|
return( -1 );
|
|
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
status = psa_mac_verify_setup( &operation, ctx->psa_hmac_key,
|
|
ctx->psa_hmac_alg );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_update( &operation, cookie, 4 );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_update( &operation, cli_id,
|
|
cli_id_len );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_verify_finish( &operation, cookie + 4,
|
|
COOKIE_HMAC_LEN );
|
|
if( status != PSA_SUCCESS )
|
|
{
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
goto exit;
|
|
}
|
|
|
|
ret = 0;
|
|
#else
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
|
|
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_SSL_INTERNAL_ERROR, ret ) );
|
|
#endif
|
|
|
|
if( ssl_cookie_hmac( &ctx->hmac_ctx, cookie,
|
|
&p, p + sizeof( ref_hmac ),
|
|
cli_id, cli_id_len ) != 0 )
|
|
ret = -1;
|
|
|
|
#if defined(MBEDTLS_THREADING_C)
|
|
if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
|
|
{
|
|
ret = MBEDTLS_ERROR_ADD( MBEDTLS_ERR_SSL_INTERNAL_ERROR,
|
|
MBEDTLS_ERR_THREADING_MUTEX_ERROR );
|
|
}
|
|
#endif
|
|
|
|
if( ret != 0 )
|
|
goto exit;
|
|
|
|
if( mbedtls_ct_memcmp( cookie + 4, ref_hmac, sizeof( ref_hmac ) ) != 0 )
|
|
{
|
|
ret = -1;
|
|
goto exit;
|
|
}
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
|
|
#if defined(MBEDTLS_HAVE_TIME)
|
|
cur_time = (unsigned long) mbedtls_time( NULL );
|
|
#else
|
|
cur_time = ctx->serial;
|
|
#endif
|
|
|
|
cookie_time = ( (unsigned long) cookie[0] << 24 ) |
|
|
( (unsigned long) cookie[1] << 16 ) |
|
|
( (unsigned long) cookie[2] << 8 ) |
|
|
( (unsigned long) cookie[3] );
|
|
|
|
if( ctx->timeout != 0 && cur_time - cookie_time > ctx->timeout )
|
|
{
|
|
ret = -1;
|
|
goto exit;
|
|
}
|
|
|
|
exit:
|
|
#if defined(MBEDTLS_USE_PSA_CRYPTO)
|
|
status = psa_mac_abort( &operation );
|
|
if( status != PSA_SUCCESS )
|
|
ret = psa_ssl_status_to_mbedtls( status );
|
|
#else
|
|
mbedtls_platform_zeroize( ref_hmac, sizeof( ref_hmac ) );
|
|
#endif /* MBEDTLS_USE_PSA_CRYPTO */
|
|
return( ret );
|
|
}
|
|
#endif /* MBEDTLS_SSL_COOKIE_C */
|