711 lines
26 KiB
C
711 lines
26 KiB
C
/**
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* PSA API key derivation demonstration
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*
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* This program calculates a key ladder: a chain of secret material, each
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* derived from the previous one in a deterministic way based on a label.
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* Two keys are identical if and only if they are derived from the same key
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* using the same label.
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*
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* The initial key is called the master key. The master key is normally
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* randomly generated, but it could itself be derived from another key.
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*
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* This program derives a series of keys called intermediate keys.
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* The first intermediate key is derived from the master key using the
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* first label passed on the command line. Each subsequent intermediate
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* key is derived from the previous one using the next label passed
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* on the command line.
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*
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* This program has four modes of operation:
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*
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* - "generate": generate a random master key.
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* - "wrap": derive a wrapping key from the last intermediate key,
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* and use that key to encrypt-and-authenticate some data.
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* - "unwrap": derive a wrapping key from the last intermediate key,
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* and use that key to decrypt-and-authenticate some
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* ciphertext created by wrap mode.
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* - "save": save the last intermediate key so that it can be reused as
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* the master key in another run of the program.
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*
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* See the usage() output for the command line usage. See the file
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* `key_ladder_demo.sh` for an example run.
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*/
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/* Copyright (C) 2018, ARM Limited, All Rights Reserved
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed under the Apache License, Version 2.0 (the "License"); you may
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* not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* This file is part of mbed TLS (https://tls.mbed.org)
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*/
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/* First include Mbed TLS headers to get the Mbed TLS configuration and
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* platform definitions that we'll use in this program. Also include
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* standard C headers for functions we'll use here. */
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#if !defined(MBEDTLS_CONFIG_FILE)
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#include "mbedtls/config.h"
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#else
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#include MBEDTLS_CONFIG_FILE
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#endif
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include "mbedtls/platform_util.h" // for mbedtls_platform_zeroize
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#include <psa/crypto.h>
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/* If the build options we need are not enabled, compile a placeholder. */
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#if !defined(MBEDTLS_SHA256_C) || !defined(MBEDTLS_MD_C) || \
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!defined(MBEDTLS_AES_C) || !defined(MBEDTLS_CCM_C) || \
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!defined(MBEDTLS_PSA_CRYPTO_C) || !defined(MBEDTLS_FS_IO)
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int main( void )
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{
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printf("MBEDTLS_SHA256_C and/or MBEDTLS_MD_C and/or "
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"MBEDTLS_AES_C and/or MBEDTLS_CCM_C and/or "
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"MBEDTLS_PSA_CRYPTO_C and/or MBEDTLS_FS_IO "
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"not defined.\n");
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return( 0 );
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}
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#else
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/* The real program starts here. */
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/* Run a system function and bail out if it fails. */
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#define SYS_CHECK( expr ) \
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do \
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{ \
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if( ! ( expr ) ) \
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{ \
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perror( #expr ); \
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status = DEMO_ERROR; \
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goto exit; \
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} \
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} \
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while( 0 )
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/* Run a PSA function and bail out if it fails. */
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#define PSA_CHECK( expr ) \
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do \
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{ \
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status = ( expr ); \
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if( status != PSA_SUCCESS ) \
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{ \
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printf( "Error %d at line %d: %s\n", \
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(int) status, \
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__LINE__, \
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#expr ); \
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goto exit; \
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} \
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} \
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while( 0 )
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/* To report operational errors in this program, use an error code that is
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* different from every PSA error code. */
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#define DEMO_ERROR 120
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/* The maximum supported key ladder depth. */
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#define MAX_LADDER_DEPTH 10
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/* Salt to use when deriving an intermediate key. */
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#define DERIVE_KEY_SALT ( (uint8_t *) "key_ladder_demo.derive" )
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#define DERIVE_KEY_SALT_LENGTH ( strlen( (const char*) DERIVE_KEY_SALT ) )
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/* Salt to use when deriving a wrapping key. */
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#define WRAPPING_KEY_SALT ( (uint8_t *) "key_ladder_demo.wrap" )
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#define WRAPPING_KEY_SALT_LENGTH ( strlen( (const char*) WRAPPING_KEY_SALT ) )
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/* Size of the key derivation keys (applies both to the master key and
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* to intermediate keys). */
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#define KEY_SIZE_BYTES 40
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/* Algorithm for key derivation. */
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#define KDF_ALG PSA_ALG_HKDF( PSA_ALG_SHA_256 )
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/* Type and size of the key used to wrap data. */
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#define WRAPPING_KEY_TYPE PSA_KEY_TYPE_AES
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#define WRAPPING_KEY_BITS 128
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/* Cipher mode used to wrap data. */
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#define WRAPPING_ALG PSA_ALG_CCM
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/* Nonce size used to wrap data. */
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#define WRAPPING_IV_SIZE 13
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/* Header used in files containing wrapped data. We'll save this header
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* directly without worrying about data representation issues such as
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* integer sizes and endianness, because the data is meant to be read
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* back by the same program on the same machine. */
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#define WRAPPED_DATA_MAGIC "key_ladder_demo" // including trailing null byte
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#define WRAPPED_DATA_MAGIC_LENGTH ( sizeof( WRAPPED_DATA_MAGIC ) )
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typedef struct
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{
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char magic[WRAPPED_DATA_MAGIC_LENGTH];
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size_t ad_size; /* Size of the additional data, which is this header. */
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size_t payload_size; /* Size of the encrypted data. */
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/* Store the IV inside the additional data. It's convenient. */
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uint8_t iv[WRAPPING_IV_SIZE];
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} wrapped_data_header_t;
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/* The modes that this program can operate in (see usage). */
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enum program_mode
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{
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MODE_GENERATE,
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MODE_SAVE,
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MODE_UNWRAP,
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MODE_WRAP
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};
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/* Save a key to a file. In the real world, you may want to export a derived
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* key sometimes, to share it with another party. */
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static psa_status_t save_key( psa_key_handle_t key_handle,
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const char *output_file_name )
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{
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psa_status_t status = PSA_SUCCESS;
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uint8_t key_data[KEY_SIZE_BYTES];
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size_t key_size;
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FILE *key_file = NULL;
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PSA_CHECK( psa_export_key( key_handle,
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key_data, sizeof( key_data ),
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&key_size ) );
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SYS_CHECK( ( key_file = fopen( output_file_name, "wb" ) ) != NULL );
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SYS_CHECK( fwrite( key_data, 1, key_size, key_file ) == key_size );
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SYS_CHECK( fclose( key_file ) == 0 );
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key_file = NULL;
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exit:
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if( key_file != NULL)
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fclose( key_file );
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return( status );
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}
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/* Generate a master key for use in this demo.
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*
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* Normally a master key would be non-exportable. For the purpose of this
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* demo, we want to save it to a file, to avoid relying on the keystore
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* capability of the PSA crypto library. */
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static psa_status_t generate( const char *key_file_name )
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{
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psa_status_t status = PSA_SUCCESS;
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psa_key_handle_t key_handle = 0;
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psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
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psa_set_key_usage_flags( &attributes,
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PSA_KEY_USAGE_DERIVE | PSA_KEY_USAGE_EXPORT );
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psa_set_key_algorithm( &attributes, KDF_ALG );
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psa_set_key_type( &attributes, PSA_KEY_TYPE_DERIVE );
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psa_set_key_bits( &attributes, PSA_BYTES_TO_BITS( KEY_SIZE_BYTES ) );
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PSA_CHECK( psa_generate_key( &attributes, &key_handle ) );
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PSA_CHECK( save_key( key_handle, key_file_name ) );
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exit:
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(void) psa_destroy_key( key_handle );
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return( status );
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}
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/* Load the master key from a file.
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*
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* In the real world, this master key would be stored in an internal memory
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* and the storage would be managed by the keystore capability of the PSA
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* crypto library. */
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static psa_status_t import_key_from_file( psa_key_usage_t usage,
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psa_algorithm_t alg,
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const char *key_file_name,
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psa_key_handle_t *master_key_handle )
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{
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psa_status_t status = PSA_SUCCESS;
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psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
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uint8_t key_data[KEY_SIZE_BYTES];
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size_t key_size;
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FILE *key_file = NULL;
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unsigned char extra_byte;
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*master_key_handle = 0;
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SYS_CHECK( ( key_file = fopen( key_file_name, "rb" ) ) != NULL );
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SYS_CHECK( ( key_size = fread( key_data, 1, sizeof( key_data ),
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key_file ) ) != 0 );
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if( fread( &extra_byte, 1, 1, key_file ) != 0 )
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{
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printf( "Key file too large (max: %u).\n",
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(unsigned) sizeof( key_data ) );
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status = DEMO_ERROR;
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goto exit;
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}
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SYS_CHECK( fclose( key_file ) == 0 );
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key_file = NULL;
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psa_set_key_usage_flags( &attributes, usage );
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psa_set_key_algorithm( &attributes, alg );
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psa_set_key_type( &attributes, PSA_KEY_TYPE_DERIVE );
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PSA_CHECK( psa_import_key( &attributes, key_data, key_size,
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master_key_handle ) );
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exit:
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if( key_file != NULL )
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fclose( key_file );
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mbedtls_platform_zeroize( key_data, sizeof( key_data ) );
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if( status != PSA_SUCCESS )
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{
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/* If the key creation hasn't happened yet or has failed,
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* *master_key_handle is 0. psa_destroy_key(0) is guaranteed to do
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* nothing and return PSA_ERROR_INVALID_HANDLE. */
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(void) psa_destroy_key( *master_key_handle );
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*master_key_handle = 0;
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}
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return( status );
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}
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/* Derive the intermediate keys, using the list of labels provided on
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* the command line. On input, *key_handle is a handle to the master key.
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* This function closes the master key. On successful output, *key_handle
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* is a handle to the final derived key. */
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static psa_status_t derive_key_ladder( const char *ladder[],
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size_t ladder_depth,
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psa_key_handle_t *key_handle )
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{
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psa_status_t status = PSA_SUCCESS;
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psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
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psa_key_derivation_operation_t operation = PSA_KEY_DERIVATION_OPERATION_INIT;
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size_t i;
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psa_set_key_usage_flags( &attributes,
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PSA_KEY_USAGE_DERIVE | PSA_KEY_USAGE_EXPORT );
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psa_set_key_algorithm( &attributes, KDF_ALG );
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psa_set_key_type( &attributes, PSA_KEY_TYPE_DERIVE );
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psa_set_key_bits( &attributes, PSA_BYTES_TO_BITS( KEY_SIZE_BYTES ) );
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/* For each label in turn, ... */
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for( i = 0; i < ladder_depth; i++ )
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{
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/* Start deriving material from the master key (if i=0) or from
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* the current intermediate key (if i>0). */
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PSA_CHECK( psa_key_derivation_setup( &operation, KDF_ALG ) );
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PSA_CHECK( psa_key_derivation_input_bytes(
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&operation, PSA_KEY_DERIVATION_INPUT_SALT,
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DERIVE_KEY_SALT, DERIVE_KEY_SALT_LENGTH ) );
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PSA_CHECK( psa_key_derivation_input_key(
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&operation, PSA_KEY_DERIVATION_INPUT_SECRET,
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*key_handle ) );
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PSA_CHECK( psa_key_derivation_input_bytes(
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&operation, PSA_KEY_DERIVATION_INPUT_INFO,
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(uint8_t*) ladder[i], strlen( ladder[i] ) ) );
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/* When the parent key is not the master key, destroy it,
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* since it is no longer needed. */
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PSA_CHECK( psa_close_key( *key_handle ) );
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*key_handle = 0;
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/* Derive the next intermediate key from the parent key. */
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PSA_CHECK( psa_key_derivation_output_key( &attributes, &operation,
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key_handle ) );
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PSA_CHECK( psa_key_derivation_abort( &operation ) );
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}
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exit:
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psa_key_derivation_abort( &operation );
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if( status != PSA_SUCCESS )
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{
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psa_close_key( *key_handle );
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*key_handle = 0;
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}
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return( status );
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}
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/* Derive a wrapping key from the last intermediate key. */
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static psa_status_t derive_wrapping_key( psa_key_usage_t usage,
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psa_key_handle_t derived_key_handle,
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psa_key_handle_t *wrapping_key_handle )
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{
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psa_status_t status = PSA_SUCCESS;
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psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
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psa_key_derivation_operation_t operation = PSA_KEY_DERIVATION_OPERATION_INIT;
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*wrapping_key_handle = 0;
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/* Set up a key derivation operation from the key derived from
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* the master key. */
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PSA_CHECK( psa_key_derivation_setup( &operation, KDF_ALG ) );
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PSA_CHECK( psa_key_derivation_input_bytes(
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&operation, PSA_KEY_DERIVATION_INPUT_SALT,
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WRAPPING_KEY_SALT, WRAPPING_KEY_SALT_LENGTH ) );
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PSA_CHECK( psa_key_derivation_input_key(
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&operation, PSA_KEY_DERIVATION_INPUT_SECRET,
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derived_key_handle ) );
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PSA_CHECK( psa_key_derivation_input_bytes(
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&operation, PSA_KEY_DERIVATION_INPUT_INFO,
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NULL, 0 ) );
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/* Create the wrapping key. */
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psa_set_key_usage_flags( &attributes, usage );
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psa_set_key_algorithm( &attributes, WRAPPING_ALG );
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psa_set_key_type( &attributes, PSA_KEY_TYPE_AES );
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psa_set_key_bits( &attributes, WRAPPING_KEY_BITS );
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PSA_CHECK( psa_key_derivation_output_key( &attributes, &operation,
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wrapping_key_handle ) );
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exit:
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psa_key_derivation_abort( &operation );
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return( status );
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}
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static psa_status_t wrap_data( const char *input_file_name,
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const char *output_file_name,
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psa_key_handle_t wrapping_key_handle )
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{
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psa_status_t status;
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FILE *input_file = NULL;
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FILE *output_file = NULL;
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long input_position;
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size_t input_size;
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size_t buffer_size = 0;
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unsigned char *buffer = NULL;
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size_t ciphertext_size;
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wrapped_data_header_t header;
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/* Find the size of the data to wrap. */
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SYS_CHECK( ( input_file = fopen( input_file_name, "rb" ) ) != NULL );
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SYS_CHECK( fseek( input_file, 0, SEEK_END ) == 0 );
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SYS_CHECK( ( input_position = ftell( input_file ) ) != -1 );
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#if LONG_MAX > SIZE_MAX
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if( input_position > SIZE_MAX )
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{
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printf( "Input file too large.\n" );
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status = DEMO_ERROR;
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goto exit;
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}
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#endif
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input_size = input_position;
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buffer_size = PSA_AEAD_ENCRYPT_OUTPUT_SIZE( WRAPPING_ALG, input_size );
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/* Check for integer overflow. */
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if( buffer_size < input_size )
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{
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printf( "Input file too large.\n" );
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status = DEMO_ERROR;
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goto exit;
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}
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/* Load the data to wrap. */
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SYS_CHECK( fseek( input_file, 0, SEEK_SET ) == 0 );
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SYS_CHECK( ( buffer = calloc( 1, buffer_size ) ) != NULL );
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SYS_CHECK( fread( buffer, 1, input_size, input_file ) == input_size );
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SYS_CHECK( fclose( input_file ) == 0 );
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input_file = NULL;
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/* Construct a header. */
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memcpy( &header.magic, WRAPPED_DATA_MAGIC, WRAPPED_DATA_MAGIC_LENGTH );
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header.ad_size = sizeof( header );
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header.payload_size = input_size;
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/* Wrap the data. */
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PSA_CHECK( psa_generate_random( header.iv, WRAPPING_IV_SIZE ) );
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PSA_CHECK( psa_aead_encrypt( wrapping_key_handle, WRAPPING_ALG,
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header.iv, WRAPPING_IV_SIZE,
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(uint8_t *) &header, sizeof( header ),
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buffer, input_size,
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buffer, buffer_size,
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&ciphertext_size ) );
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/* Write the output. */
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SYS_CHECK( ( output_file = fopen( output_file_name, "wb" ) ) != NULL );
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SYS_CHECK( fwrite( &header, 1, sizeof( header ),
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output_file ) == sizeof( header ) );
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SYS_CHECK( fwrite( buffer, 1, ciphertext_size,
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output_file ) == ciphertext_size );
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SYS_CHECK( fclose( output_file ) == 0 );
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output_file = NULL;
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exit:
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if( input_file != NULL )
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fclose( input_file );
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if( output_file != NULL )
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fclose( output_file );
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if( buffer != NULL )
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mbedtls_platform_zeroize( buffer, buffer_size );
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free( buffer );
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return( status );
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}
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static psa_status_t unwrap_data( const char *input_file_name,
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const char *output_file_name,
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psa_key_handle_t wrapping_key_handle )
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{
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psa_status_t status;
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FILE *input_file = NULL;
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FILE *output_file = NULL;
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unsigned char *buffer = NULL;
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size_t ciphertext_size = 0;
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size_t plaintext_size;
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wrapped_data_header_t header;
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unsigned char extra_byte;
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/* Load and validate the header. */
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SYS_CHECK( ( input_file = fopen( input_file_name, "rb" ) ) != NULL );
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SYS_CHECK( fread( &header, 1, sizeof( header ),
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input_file ) == sizeof( header ) );
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if( memcmp( &header.magic, WRAPPED_DATA_MAGIC,
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WRAPPED_DATA_MAGIC_LENGTH ) != 0 )
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{
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printf( "The input does not start with a valid magic header.\n" );
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|
status = DEMO_ERROR;
|
|
goto exit;
|
|
}
|
|
if( header.ad_size != sizeof( header ) )
|
|
{
|
|
printf( "The header size is not correct.\n" );
|
|
status = DEMO_ERROR;
|
|
goto exit;
|
|
}
|
|
ciphertext_size =
|
|
PSA_AEAD_ENCRYPT_OUTPUT_SIZE( WRAPPING_ALG, header.payload_size );
|
|
/* Check for integer overflow. */
|
|
if( ciphertext_size < header.payload_size )
|
|
{
|
|
printf( "Input file too large.\n" );
|
|
status = DEMO_ERROR;
|
|
goto exit;
|
|
}
|
|
|
|
/* Load the payload data. */
|
|
SYS_CHECK( ( buffer = calloc( 1, ciphertext_size ) ) != NULL );
|
|
SYS_CHECK( fread( buffer, 1, ciphertext_size,
|
|
input_file ) == ciphertext_size );
|
|
if( fread( &extra_byte, 1, 1, input_file ) != 0 )
|
|
{
|
|
printf( "Extra garbage after ciphertext\n" );
|
|
status = DEMO_ERROR;
|
|
goto exit;
|
|
}
|
|
SYS_CHECK( fclose( input_file ) == 0 );
|
|
input_file = NULL;
|
|
|
|
/* Unwrap the data. */
|
|
PSA_CHECK( psa_aead_decrypt( wrapping_key_handle, WRAPPING_ALG,
|
|
header.iv, WRAPPING_IV_SIZE,
|
|
(uint8_t *) &header, sizeof( header ),
|
|
buffer, ciphertext_size,
|
|
buffer, ciphertext_size,
|
|
&plaintext_size ) );
|
|
if( plaintext_size != header.payload_size )
|
|
{
|
|
printf( "Incorrect payload size in the header.\n" );
|
|
status = DEMO_ERROR;
|
|
goto exit;
|
|
}
|
|
|
|
/* Write the output. */
|
|
SYS_CHECK( ( output_file = fopen( output_file_name, "wb" ) ) != NULL );
|
|
SYS_CHECK( fwrite( buffer, 1, plaintext_size,
|
|
output_file ) == plaintext_size );
|
|
SYS_CHECK( fclose( output_file ) == 0 );
|
|
output_file = NULL;
|
|
|
|
exit:
|
|
if( input_file != NULL )
|
|
fclose( input_file );
|
|
if( output_file != NULL )
|
|
fclose( output_file );
|
|
if( buffer != NULL )
|
|
mbedtls_platform_zeroize( buffer, ciphertext_size );
|
|
free( buffer );
|
|
return( status );
|
|
}
|
|
|
|
static psa_status_t run( enum program_mode mode,
|
|
const char *key_file_name,
|
|
const char *ladder[], size_t ladder_depth,
|
|
const char *input_file_name,
|
|
const char *output_file_name )
|
|
{
|
|
psa_status_t status = PSA_SUCCESS;
|
|
psa_key_handle_t derivation_key_handle = 0;
|
|
psa_key_handle_t wrapping_key_handle = 0;
|
|
|
|
/* Initialize the PSA crypto library. */
|
|
PSA_CHECK( psa_crypto_init( ) );
|
|
|
|
/* Generate mode is unlike the others. Generate the master key and exit. */
|
|
if( mode == MODE_GENERATE )
|
|
return( generate( key_file_name ) );
|
|
|
|
/* Read the master key. */
|
|
PSA_CHECK( import_key_from_file( PSA_KEY_USAGE_DERIVE | PSA_KEY_USAGE_EXPORT,
|
|
KDF_ALG,
|
|
key_file_name,
|
|
&derivation_key_handle ) );
|
|
|
|
/* Calculate the derived key for this session. */
|
|
PSA_CHECK( derive_key_ladder( ladder, ladder_depth,
|
|
&derivation_key_handle ) );
|
|
|
|
switch( mode )
|
|
{
|
|
case MODE_SAVE:
|
|
PSA_CHECK( save_key( derivation_key_handle, output_file_name ) );
|
|
break;
|
|
case MODE_UNWRAP:
|
|
PSA_CHECK( derive_wrapping_key( PSA_KEY_USAGE_DECRYPT,
|
|
derivation_key_handle,
|
|
&wrapping_key_handle ) );
|
|
PSA_CHECK( unwrap_data( input_file_name, output_file_name,
|
|
wrapping_key_handle ) );
|
|
break;
|
|
case MODE_WRAP:
|
|
PSA_CHECK( derive_wrapping_key( PSA_KEY_USAGE_ENCRYPT,
|
|
derivation_key_handle,
|
|
&wrapping_key_handle ) );
|
|
PSA_CHECK( wrap_data( input_file_name, output_file_name,
|
|
wrapping_key_handle ) );
|
|
break;
|
|
default:
|
|
/* Unreachable but some compilers don't realize it. */
|
|
break;
|
|
}
|
|
|
|
exit:
|
|
/* Close any remaining key. Deinitializing the crypto library would do
|
|
* this anyway, but explicitly closing handles makes the code easier
|
|
* to reuse. */
|
|
(void) psa_close_key( derivation_key_handle );
|
|
(void) psa_close_key( wrapping_key_handle );
|
|
/* Deinitialize the PSA crypto library. */
|
|
mbedtls_psa_crypto_free( );
|
|
return( status );
|
|
}
|
|
|
|
static void usage( void )
|
|
{
|
|
printf( "Usage: key_ladder_demo MODE [OPTION=VALUE]...\n" );
|
|
printf( "Demonstrate the usage of a key derivation ladder.\n" );
|
|
printf( "\n" );
|
|
printf( "Modes:\n" );
|
|
printf( " generate Generate the master key\n" );
|
|
printf( " save Save the derived key\n" );
|
|
printf( " unwrap Unwrap (decrypt) input with the derived key\n" );
|
|
printf( " wrap Wrap (encrypt) input with the derived key\n" );
|
|
printf( "\n" );
|
|
printf( "Options:\n" );
|
|
printf( " input=FILENAME Input file (required for wrap/unwrap)\n" );
|
|
printf( " master=FILENAME File containing the master key (default: master.key)\n" );
|
|
printf( " output=FILENAME Output file (required for save/wrap/unwrap)\n" );
|
|
printf( " label=TEXT Label for the key derivation.\n" );
|
|
printf( " This may be repeated multiple times.\n" );
|
|
printf( " To get the same key, you must use the same master key\n" );
|
|
printf( " and the same sequence of labels.\n" );
|
|
}
|
|
|
|
#if defined(MBEDTLS_CHECK_PARAMS)
|
|
#include "mbedtls/platform_util.h"
|
|
void mbedtls_param_failed( const char *failure_condition,
|
|
const char *file,
|
|
int line )
|
|
{
|
|
printf( "%s:%i: Input param failed - %s\n",
|
|
file, line, failure_condition );
|
|
exit( EXIT_FAILURE );
|
|
}
|
|
#endif
|
|
|
|
int main( int argc, char *argv[] )
|
|
{
|
|
const char *key_file_name = "master.key";
|
|
const char *input_file_name = NULL;
|
|
const char *output_file_name = NULL;
|
|
const char *ladder[MAX_LADDER_DEPTH];
|
|
size_t ladder_depth = 0;
|
|
int i;
|
|
enum program_mode mode;
|
|
psa_status_t status;
|
|
|
|
if( argc <= 1 ||
|
|
strcmp( argv[1], "help" ) == 0 ||
|
|
strcmp( argv[1], "-help" ) == 0 ||
|
|
strcmp( argv[1], "--help" ) == 0 )
|
|
{
|
|
usage( );
|
|
return( EXIT_SUCCESS );
|
|
}
|
|
|
|
for( i = 2; i < argc; i++ )
|
|
{
|
|
char *q = strchr( argv[i], '=' );
|
|
if( q == NULL )
|
|
{
|
|
printf( "Missing argument to option %s\n", argv[i] );
|
|
goto usage_failure;
|
|
}
|
|
*q = 0;
|
|
++q;
|
|
if( strcmp( argv[i], "input" ) == 0 )
|
|
input_file_name = q;
|
|
else if( strcmp( argv[i], "label" ) == 0 )
|
|
{
|
|
if( ladder_depth == MAX_LADDER_DEPTH )
|
|
{
|
|
printf( "Maximum ladder depth %u exceeded.\n",
|
|
(unsigned) MAX_LADDER_DEPTH );
|
|
return( EXIT_FAILURE );
|
|
}
|
|
ladder[ladder_depth] = q;
|
|
++ladder_depth;
|
|
}
|
|
else if( strcmp( argv[i], "master" ) == 0 )
|
|
key_file_name = q;
|
|
else if( strcmp( argv[i], "output" ) == 0 )
|
|
output_file_name = q;
|
|
else
|
|
{
|
|
printf( "Unknown option: %s\n", argv[i] );
|
|
goto usage_failure;
|
|
}
|
|
}
|
|
|
|
if( strcmp( argv[1], "generate" ) == 0 )
|
|
mode = MODE_GENERATE;
|
|
else if( strcmp( argv[1], "save" ) == 0 )
|
|
mode = MODE_SAVE;
|
|
else if( strcmp( argv[1], "unwrap" ) == 0 )
|
|
mode = MODE_UNWRAP;
|
|
else if( strcmp( argv[1], "wrap" ) == 0 )
|
|
mode = MODE_WRAP;
|
|
else
|
|
{
|
|
printf( "Unknown action: %s\n", argv[1] );
|
|
goto usage_failure;
|
|
}
|
|
|
|
if( input_file_name == NULL &&
|
|
( mode == MODE_WRAP || mode == MODE_UNWRAP ) )
|
|
{
|
|
printf( "Required argument missing: input\n" );
|
|
return( DEMO_ERROR );
|
|
}
|
|
if( output_file_name == NULL &&
|
|
( mode == MODE_SAVE || mode == MODE_WRAP || mode == MODE_UNWRAP ) )
|
|
{
|
|
printf( "Required argument missing: output\n" );
|
|
return( DEMO_ERROR );
|
|
}
|
|
|
|
status = run( mode, key_file_name,
|
|
ladder, ladder_depth,
|
|
input_file_name, output_file_name );
|
|
return( status == PSA_SUCCESS ?
|
|
EXIT_SUCCESS :
|
|
EXIT_FAILURE );
|
|
|
|
usage_failure:
|
|
usage( );
|
|
return( EXIT_FAILURE );
|
|
}
|
|
#endif /* MBEDTLS_SHA256_C && MBEDTLS_MD_C && MBEDTLS_AES_C && MBEDTLS_CCM_C && MBEDTLS_PSA_CRYPTO_C && MBEDTLS_FS_IO */
|