library/ssl_cookie.c - third_party/github/ARMmbed/mbedtls - Git at Google

 /*
  *  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-1, SHA-256, SHA-384 is
  * available. Try SHA-256 first, 384 wastes resources
  */
 #if defined(MBEDTLS_HAS_ALG_SHA_224_VIA_LOWLEVEL_OR_PSA)
 #define COOKIE_MD           MBEDTLS_MD_SHA224
 #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
 #elif defined(MBEDTLS_HAS_ALG_SHA_1_VIA_LOWLEVEL_OR_PSA)
 #define COOKIE_MD           MBEDTLS_MD_SHA1
 #define COOKIE_MD_OUTLEN    20
 #define COOKIE_HMAC_LEN     20
 #else
 #error "DTLS hello verify needs SHA-1 or SHA-2"
 #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 */
	/*
	* 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-1, SHA-256, SHA-384 is
	* available. Try SHA-256 first, 384 wastes resources
	*/
	#if defined(MBEDTLS_HAS_ALG_SHA_224_VIA_LOWLEVEL_OR_PSA)
	#define COOKIE_MD MBEDTLS_MD_SHA224
	#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
	#elif defined(MBEDTLS_HAS_ALG_SHA_1_VIA_LOWLEVEL_OR_PSA)
	#define COOKIE_MD MBEDTLS_MD_SHA1
	#define COOKIE_MD_OUTLEN 20
	#define COOKIE_HMAC_LEN 20
	#else
	#error "DTLS hello verify needs SHA-1 or SHA-2"
	#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 */