Marco Zecchini / Mbed OS Example_RTOS

Rtos API example

mbed-os/features/mbedtls/src/arc4.c@0:9fca2b23d0ba, 2019-02-23 (annotated)

Committer:
marcozecchini
Date:
Sat Feb 23 12:13:36 2019 +0000
Revision:
0:9fca2b23d0ba
final commit

Who changed what in which revision?

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marcozecchini 0:9fca2b23d0ba 1 /*
marcozecchini 0:9fca2b23d0ba 2 * An implementation of the ARCFOUR algorithm
marcozecchini 0:9fca2b23d0ba 3 *
marcozecchini 0:9fca2b23d0ba 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
marcozecchini 0:9fca2b23d0ba 5 * SPDX-License-Identifier: Apache-2.0
marcozecchini 0:9fca2b23d0ba 6 *
marcozecchini 0:9fca2b23d0ba 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
marcozecchini 0:9fca2b23d0ba 8 * not use this file except in compliance with the License.
marcozecchini 0:9fca2b23d0ba 9 * You may obtain a copy of the License at
marcozecchini 0:9fca2b23d0ba 10 *
marcozecchini 0:9fca2b23d0ba 11 * http://www.apache.org/licenses/LICENSE-2.0
marcozecchini 0:9fca2b23d0ba 12 *
marcozecchini 0:9fca2b23d0ba 13 * Unless required by applicable law or agreed to in writing, software
marcozecchini 0:9fca2b23d0ba 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
marcozecchini 0:9fca2b23d0ba 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
marcozecchini 0:9fca2b23d0ba 16 * See the License for the specific language governing permissions and
marcozecchini 0:9fca2b23d0ba 17 * limitations under the License.
marcozecchini 0:9fca2b23d0ba 18 *
marcozecchini 0:9fca2b23d0ba 19 * This file is part of mbed TLS (https://tls.mbed.org)
marcozecchini 0:9fca2b23d0ba 20 */
marcozecchini 0:9fca2b23d0ba 21 /*
marcozecchini 0:9fca2b23d0ba 22 * The ARCFOUR algorithm was publicly disclosed on 94/09.
marcozecchini 0:9fca2b23d0ba 23 *
marcozecchini 0:9fca2b23d0ba 24 * http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0
marcozecchini 0:9fca2b23d0ba 25 */
marcozecchini 0:9fca2b23d0ba 26
marcozecchini 0:9fca2b23d0ba 27 #if !defined(MBEDTLS_CONFIG_FILE)
marcozecchini 0:9fca2b23d0ba 28 #include "mbedtls/config.h"
marcozecchini 0:9fca2b23d0ba 29 #else
marcozecchini 0:9fca2b23d0ba 30 #include MBEDTLS_CONFIG_FILE
marcozecchini 0:9fca2b23d0ba 31 #endif
marcozecchini 0:9fca2b23d0ba 32
marcozecchini 0:9fca2b23d0ba 33 #if defined(MBEDTLS_ARC4_C)
marcozecchini 0:9fca2b23d0ba 34
marcozecchini 0:9fca2b23d0ba 35 #include "mbedtls/arc4.h"
marcozecchini 0:9fca2b23d0ba 36
marcozecchini 0:9fca2b23d0ba 37 #include <string.h>
marcozecchini 0:9fca2b23d0ba 38
marcozecchini 0:9fca2b23d0ba 39 #if defined(MBEDTLS_SELF_TEST)
marcozecchini 0:9fca2b23d0ba 40 #if defined(MBEDTLS_PLATFORM_C)
marcozecchini 0:9fca2b23d0ba 41 #include "mbedtls/platform.h"
marcozecchini 0:9fca2b23d0ba 42 #else
marcozecchini 0:9fca2b23d0ba 43 #include <stdio.h>
marcozecchini 0:9fca2b23d0ba 44 #define mbedtls_printf printf
marcozecchini 0:9fca2b23d0ba 45 #endif /* MBEDTLS_PLATFORM_C */
marcozecchini 0:9fca2b23d0ba 46 #endif /* MBEDTLS_SELF_TEST */
marcozecchini 0:9fca2b23d0ba 47
marcozecchini 0:9fca2b23d0ba 48 #if !defined(MBEDTLS_ARC4_ALT)
marcozecchini 0:9fca2b23d0ba 49
marcozecchini 0:9fca2b23d0ba 50 /* Implementation that should never be optimized out by the compiler */
marcozecchini 0:9fca2b23d0ba 51 static void mbedtls_zeroize( void *v, size_t n ) {
marcozecchini 0:9fca2b23d0ba 52 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
marcozecchini 0:9fca2b23d0ba 53 }
marcozecchini 0:9fca2b23d0ba 54
marcozecchini 0:9fca2b23d0ba 55 void mbedtls_arc4_init( mbedtls_arc4_context *ctx )
marcozecchini 0:9fca2b23d0ba 56 {
marcozecchini 0:9fca2b23d0ba 57 memset( ctx, 0, sizeof( mbedtls_arc4_context ) );
marcozecchini 0:9fca2b23d0ba 58 }
marcozecchini 0:9fca2b23d0ba 59
marcozecchini 0:9fca2b23d0ba 60 void mbedtls_arc4_free( mbedtls_arc4_context *ctx )
marcozecchini 0:9fca2b23d0ba 61 {
marcozecchini 0:9fca2b23d0ba 62 if( ctx == NULL )
marcozecchini 0:9fca2b23d0ba 63 return;
marcozecchini 0:9fca2b23d0ba 64
marcozecchini 0:9fca2b23d0ba 65 mbedtls_zeroize( ctx, sizeof( mbedtls_arc4_context ) );
marcozecchini 0:9fca2b23d0ba 66 }
marcozecchini 0:9fca2b23d0ba 67
marcozecchini 0:9fca2b23d0ba 68 /*
marcozecchini 0:9fca2b23d0ba 69 * ARC4 key schedule
marcozecchini 0:9fca2b23d0ba 70 */
marcozecchini 0:9fca2b23d0ba 71 void mbedtls_arc4_setup( mbedtls_arc4_context *ctx, const unsigned char *key,
marcozecchini 0:9fca2b23d0ba 72 unsigned int keylen )
marcozecchini 0:9fca2b23d0ba 73 {
marcozecchini 0:9fca2b23d0ba 74 int i, j, a;
marcozecchini 0:9fca2b23d0ba 75 unsigned int k;
marcozecchini 0:9fca2b23d0ba 76 unsigned char *m;
marcozecchini 0:9fca2b23d0ba 77
marcozecchini 0:9fca2b23d0ba 78 ctx->x = 0;
marcozecchini 0:9fca2b23d0ba 79 ctx->y = 0;
marcozecchini 0:9fca2b23d0ba 80 m = ctx->m;
marcozecchini 0:9fca2b23d0ba 81
marcozecchini 0:9fca2b23d0ba 82 for( i = 0; i < 256; i++ )
marcozecchini 0:9fca2b23d0ba 83 m[i] = (unsigned char) i;
marcozecchini 0:9fca2b23d0ba 84
marcozecchini 0:9fca2b23d0ba 85 j = k = 0;
marcozecchini 0:9fca2b23d0ba 86
marcozecchini 0:9fca2b23d0ba 87 for( i = 0; i < 256; i++, k++ )
marcozecchini 0:9fca2b23d0ba 88 {
marcozecchini 0:9fca2b23d0ba 89 if( k >= keylen ) k = 0;
marcozecchini 0:9fca2b23d0ba 90
marcozecchini 0:9fca2b23d0ba 91 a = m[i];
marcozecchini 0:9fca2b23d0ba 92 j = ( j + a + key[k] ) & 0xFF;
marcozecchini 0:9fca2b23d0ba 93 m[i] = m[j];
marcozecchini 0:9fca2b23d0ba 94 m[j] = (unsigned char) a;
marcozecchini 0:9fca2b23d0ba 95 }
marcozecchini 0:9fca2b23d0ba 96 }
marcozecchini 0:9fca2b23d0ba 97
marcozecchini 0:9fca2b23d0ba 98 /*
marcozecchini 0:9fca2b23d0ba 99 * ARC4 cipher function
marcozecchini 0:9fca2b23d0ba 100 */
marcozecchini 0:9fca2b23d0ba 101 int mbedtls_arc4_crypt( mbedtls_arc4_context *ctx, size_t length, const unsigned char *input,
marcozecchini 0:9fca2b23d0ba 102 unsigned char *output )
marcozecchini 0:9fca2b23d0ba 103 {
marcozecchini 0:9fca2b23d0ba 104 int x, y, a, b;
marcozecchini 0:9fca2b23d0ba 105 size_t i;
marcozecchini 0:9fca2b23d0ba 106 unsigned char *m;
marcozecchini 0:9fca2b23d0ba 107
marcozecchini 0:9fca2b23d0ba 108 x = ctx->x;
marcozecchini 0:9fca2b23d0ba 109 y = ctx->y;
marcozecchini 0:9fca2b23d0ba 110 m = ctx->m;
marcozecchini 0:9fca2b23d0ba 111
marcozecchini 0:9fca2b23d0ba 112 for( i = 0; i < length; i++ )
marcozecchini 0:9fca2b23d0ba 113 {
marcozecchini 0:9fca2b23d0ba 114 x = ( x + 1 ) & 0xFF; a = m[x];
marcozecchini 0:9fca2b23d0ba 115 y = ( y + a ) & 0xFF; b = m[y];
marcozecchini 0:9fca2b23d0ba 116
marcozecchini 0:9fca2b23d0ba 117 m[x] = (unsigned char) b;
marcozecchini 0:9fca2b23d0ba 118 m[y] = (unsigned char) a;
marcozecchini 0:9fca2b23d0ba 119
marcozecchini 0:9fca2b23d0ba 120 output[i] = (unsigned char)
marcozecchini 0:9fca2b23d0ba 121 ( input[i] ^ m[(unsigned char)( a + b )] );
marcozecchini 0:9fca2b23d0ba 122 }
marcozecchini 0:9fca2b23d0ba 123
marcozecchini 0:9fca2b23d0ba 124 ctx->x = x;
marcozecchini 0:9fca2b23d0ba 125 ctx->y = y;
marcozecchini 0:9fca2b23d0ba 126
marcozecchini 0:9fca2b23d0ba 127 return( 0 );
marcozecchini 0:9fca2b23d0ba 128 }
marcozecchini 0:9fca2b23d0ba 129
marcozecchini 0:9fca2b23d0ba 130 #endif /* !MBEDTLS_ARC4_ALT */
marcozecchini 0:9fca2b23d0ba 131
marcozecchini 0:9fca2b23d0ba 132 #if defined(MBEDTLS_SELF_TEST)
marcozecchini 0:9fca2b23d0ba 133 /*
marcozecchini 0:9fca2b23d0ba 134 * ARC4 tests vectors as posted by Eric Rescorla in sep. 1994:
marcozecchini 0:9fca2b23d0ba 135 *
marcozecchini 0:9fca2b23d0ba 136 * http://groups.google.com/group/comp.security.misc/msg/10a300c9d21afca0
marcozecchini 0:9fca2b23d0ba 137 */
marcozecchini 0:9fca2b23d0ba 138 static const unsigned char arc4_test_key[3][8] =
marcozecchini 0:9fca2b23d0ba 139 {
marcozecchini 0:9fca2b23d0ba 140 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
marcozecchini 0:9fca2b23d0ba 141 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
marcozecchini 0:9fca2b23d0ba 142 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
marcozecchini 0:9fca2b23d0ba 143 };
marcozecchini 0:9fca2b23d0ba 144
marcozecchini 0:9fca2b23d0ba 145 static const unsigned char arc4_test_pt[3][8] =
marcozecchini 0:9fca2b23d0ba 146 {
marcozecchini 0:9fca2b23d0ba 147 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
marcozecchini 0:9fca2b23d0ba 148 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
marcozecchini 0:9fca2b23d0ba 149 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
marcozecchini 0:9fca2b23d0ba 150 };
marcozecchini 0:9fca2b23d0ba 151
marcozecchini 0:9fca2b23d0ba 152 static const unsigned char arc4_test_ct[3][8] =
marcozecchini 0:9fca2b23d0ba 153 {
marcozecchini 0:9fca2b23d0ba 154 { 0x75, 0xB7, 0x87, 0x80, 0x99, 0xE0, 0xC5, 0x96 },
marcozecchini 0:9fca2b23d0ba 155 { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 },
marcozecchini 0:9fca2b23d0ba 156 { 0xDE, 0x18, 0x89, 0x41, 0xA3, 0x37, 0x5D, 0x3A }
marcozecchini 0:9fca2b23d0ba 157 };
marcozecchini 0:9fca2b23d0ba 158
marcozecchini 0:9fca2b23d0ba 159 /*
marcozecchini 0:9fca2b23d0ba 160 * Checkup routine
marcozecchini 0:9fca2b23d0ba 161 */
marcozecchini 0:9fca2b23d0ba 162 int mbedtls_arc4_self_test( int verbose )
marcozecchini 0:9fca2b23d0ba 163 {
marcozecchini 0:9fca2b23d0ba 164 int i, ret = 0;
marcozecchini 0:9fca2b23d0ba 165 unsigned char ibuf[8];
marcozecchini 0:9fca2b23d0ba 166 unsigned char obuf[8];
marcozecchini 0:9fca2b23d0ba 167 mbedtls_arc4_context ctx;
marcozecchini 0:9fca2b23d0ba 168
marcozecchini 0:9fca2b23d0ba 169 mbedtls_arc4_init( &ctx );
marcozecchini 0:9fca2b23d0ba 170
marcozecchini 0:9fca2b23d0ba 171 for( i = 0; i < 3; i++ )
marcozecchini 0:9fca2b23d0ba 172 {
marcozecchini 0:9fca2b23d0ba 173 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 174 mbedtls_printf( " ARC4 test #%d: ", i + 1 );
marcozecchini 0:9fca2b23d0ba 175
marcozecchini 0:9fca2b23d0ba 176 memcpy( ibuf, arc4_test_pt[i], 8 );
marcozecchini 0:9fca2b23d0ba 177
marcozecchini 0:9fca2b23d0ba 178 mbedtls_arc4_setup( &ctx, arc4_test_key[i], 8 );
marcozecchini 0:9fca2b23d0ba 179 mbedtls_arc4_crypt( &ctx, 8, ibuf, obuf );
marcozecchini 0:9fca2b23d0ba 180
marcozecchini 0:9fca2b23d0ba 181 if( memcmp( obuf, arc4_test_ct[i], 8 ) != 0 )
marcozecchini 0:9fca2b23d0ba 182 {
marcozecchini 0:9fca2b23d0ba 183 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 184 mbedtls_printf( "failed\n" );
marcozecchini 0:9fca2b23d0ba 185
marcozecchini 0:9fca2b23d0ba 186 ret = 1;
marcozecchini 0:9fca2b23d0ba 187 goto exit;
marcozecchini 0:9fca2b23d0ba 188 }
marcozecchini 0:9fca2b23d0ba 189
marcozecchini 0:9fca2b23d0ba 190 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 191 mbedtls_printf( "passed\n" );
marcozecchini 0:9fca2b23d0ba 192 }
marcozecchini 0:9fca2b23d0ba 193
marcozecchini 0:9fca2b23d0ba 194 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 195 mbedtls_printf( "\n" );
marcozecchini 0:9fca2b23d0ba 196
marcozecchini 0:9fca2b23d0ba 197 exit:
marcozecchini 0:9fca2b23d0ba 198 mbedtls_arc4_free( &ctx );
marcozecchini 0:9fca2b23d0ba 199
marcozecchini 0:9fca2b23d0ba 200 return( ret );
marcozecchini 0:9fca2b23d0ba 201 }
marcozecchini 0:9fca2b23d0ba 202
marcozecchini 0:9fca2b23d0ba 203 #endif /* MBEDTLS_SELF_TEST */
marcozecchini 0:9fca2b23d0ba 204
marcozecchini 0:9fca2b23d0ba 205 #endif /* MBEDTLS_ARC4_C */