Kev Mann / mbed-dev-OS5_10_4

RTC auf true

features/mbedtls/src/arc4.c@0:38ceb79fef03, 2018-11-28 (annotated)

Committer:
kevman
Date:
Wed Nov 28 15:10:15 2018 +0000
Revision:
0:38ceb79fef03
RTC modified

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kevman 0:38ceb79fef03 1 /*
kevman 0:38ceb79fef03 2 * An implementation of the ARCFOUR algorithm
kevman 0:38ceb79fef03 3 *
kevman 0:38ceb79fef03 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
kevman 0:38ceb79fef03 5 * SPDX-License-Identifier: Apache-2.0
kevman 0:38ceb79fef03 6 *
kevman 0:38ceb79fef03 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
kevman 0:38ceb79fef03 8 * not use this file except in compliance with the License.
kevman 0:38ceb79fef03 9 * You may obtain a copy of the License at
kevman 0:38ceb79fef03 10 *
kevman 0:38ceb79fef03 11 * http://www.apache.org/licenses/LICENSE-2.0
kevman 0:38ceb79fef03 12 *
kevman 0:38ceb79fef03 13 * Unless required by applicable law or agreed to in writing, software
kevman 0:38ceb79fef03 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
kevman 0:38ceb79fef03 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
kevman 0:38ceb79fef03 16 * See the License for the specific language governing permissions and
kevman 0:38ceb79fef03 17 * limitations under the License.
kevman 0:38ceb79fef03 18 *
kevman 0:38ceb79fef03 19 * This file is part of mbed TLS (https://tls.mbed.org)
kevman 0:38ceb79fef03 20 */
kevman 0:38ceb79fef03 21 /*
kevman 0:38ceb79fef03 22 * The ARCFOUR algorithm was publicly disclosed on 94/09.
kevman 0:38ceb79fef03 23 *
kevman 0:38ceb79fef03 24 * http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0
kevman 0:38ceb79fef03 25 */
kevman 0:38ceb79fef03 26
kevman 0:38ceb79fef03 27 #if !defined(MBEDTLS_CONFIG_FILE)
kevman 0:38ceb79fef03 28 #include "mbedtls/config.h"
kevman 0:38ceb79fef03 29 #else
kevman 0:38ceb79fef03 30 #include MBEDTLS_CONFIG_FILE
kevman 0:38ceb79fef03 31 #endif
kevman 0:38ceb79fef03 32
kevman 0:38ceb79fef03 33 #if defined(MBEDTLS_ARC4_C)
kevman 0:38ceb79fef03 34
kevman 0:38ceb79fef03 35 #include "mbedtls/arc4.h"
kevman 0:38ceb79fef03 36 #include "mbedtls/platform_util.h"
kevman 0:38ceb79fef03 37
kevman 0:38ceb79fef03 38 #include <string.h>
kevman 0:38ceb79fef03 39
kevman 0:38ceb79fef03 40 #if defined(MBEDTLS_SELF_TEST)
kevman 0:38ceb79fef03 41 #if defined(MBEDTLS_PLATFORM_C)
kevman 0:38ceb79fef03 42 #include "mbedtls/platform.h"
kevman 0:38ceb79fef03 43 #else
kevman 0:38ceb79fef03 44 #include <stdio.h>
kevman 0:38ceb79fef03 45 #define mbedtls_printf printf
kevman 0:38ceb79fef03 46 #endif /* MBEDTLS_PLATFORM_C */
kevman 0:38ceb79fef03 47 #endif /* MBEDTLS_SELF_TEST */
kevman 0:38ceb79fef03 48
kevman 0:38ceb79fef03 49 #if !defined(MBEDTLS_ARC4_ALT)
kevman 0:38ceb79fef03 50
kevman 0:38ceb79fef03 51 void mbedtls_arc4_init( mbedtls_arc4_context *ctx )
kevman 0:38ceb79fef03 52 {
kevman 0:38ceb79fef03 53 memset( ctx, 0, sizeof( mbedtls_arc4_context ) );
kevman 0:38ceb79fef03 54 }
kevman 0:38ceb79fef03 55
kevman 0:38ceb79fef03 56 void mbedtls_arc4_free( mbedtls_arc4_context *ctx )
kevman 0:38ceb79fef03 57 {
kevman 0:38ceb79fef03 58 if( ctx == NULL )
kevman 0:38ceb79fef03 59 return;
kevman 0:38ceb79fef03 60
kevman 0:38ceb79fef03 61 mbedtls_platform_zeroize( ctx, sizeof( mbedtls_arc4_context ) );
kevman 0:38ceb79fef03 62 }
kevman 0:38ceb79fef03 63
kevman 0:38ceb79fef03 64 /*
kevman 0:38ceb79fef03 65 * ARC4 key schedule
kevman 0:38ceb79fef03 66 */
kevman 0:38ceb79fef03 67 void mbedtls_arc4_setup( mbedtls_arc4_context *ctx, const unsigned char *key,
kevman 0:38ceb79fef03 68 unsigned int keylen )
kevman 0:38ceb79fef03 69 {
kevman 0:38ceb79fef03 70 int i, j, a;
kevman 0:38ceb79fef03 71 unsigned int k;
kevman 0:38ceb79fef03 72 unsigned char *m;
kevman 0:38ceb79fef03 73
kevman 0:38ceb79fef03 74 ctx->x = 0;
kevman 0:38ceb79fef03 75 ctx->y = 0;
kevman 0:38ceb79fef03 76 m = ctx->m;
kevman 0:38ceb79fef03 77
kevman 0:38ceb79fef03 78 for( i = 0; i < 256; i++ )
kevman 0:38ceb79fef03 79 m[i] = (unsigned char) i;
kevman 0:38ceb79fef03 80
kevman 0:38ceb79fef03 81 j = k = 0;
kevman 0:38ceb79fef03 82
kevman 0:38ceb79fef03 83 for( i = 0; i < 256; i++, k++ )
kevman 0:38ceb79fef03 84 {
kevman 0:38ceb79fef03 85 if( k >= keylen ) k = 0;
kevman 0:38ceb79fef03 86
kevman 0:38ceb79fef03 87 a = m[i];
kevman 0:38ceb79fef03 88 j = ( j + a + key[k] ) & 0xFF;
kevman 0:38ceb79fef03 89 m[i] = m[j];
kevman 0:38ceb79fef03 90 m[j] = (unsigned char) a;
kevman 0:38ceb79fef03 91 }
kevman 0:38ceb79fef03 92 }
kevman 0:38ceb79fef03 93
kevman 0:38ceb79fef03 94 /*
kevman 0:38ceb79fef03 95 * ARC4 cipher function
kevman 0:38ceb79fef03 96 */
kevman 0:38ceb79fef03 97 int mbedtls_arc4_crypt( mbedtls_arc4_context *ctx, size_t length, const unsigned char *input,
kevman 0:38ceb79fef03 98 unsigned char *output )
kevman 0:38ceb79fef03 99 {
kevman 0:38ceb79fef03 100 int x, y, a, b;
kevman 0:38ceb79fef03 101 size_t i;
kevman 0:38ceb79fef03 102 unsigned char *m;
kevman 0:38ceb79fef03 103
kevman 0:38ceb79fef03 104 x = ctx->x;
kevman 0:38ceb79fef03 105 y = ctx->y;
kevman 0:38ceb79fef03 106 m = ctx->m;
kevman 0:38ceb79fef03 107
kevman 0:38ceb79fef03 108 for( i = 0; i < length; i++ )
kevman 0:38ceb79fef03 109 {
kevman 0:38ceb79fef03 110 x = ( x + 1 ) & 0xFF; a = m[x];
kevman 0:38ceb79fef03 111 y = ( y + a ) & 0xFF; b = m[y];
kevman 0:38ceb79fef03 112
kevman 0:38ceb79fef03 113 m[x] = (unsigned char) b;
kevman 0:38ceb79fef03 114 m[y] = (unsigned char) a;
kevman 0:38ceb79fef03 115
kevman 0:38ceb79fef03 116 output[i] = (unsigned char)
kevman 0:38ceb79fef03 117 ( input[i] ^ m[(unsigned char)( a + b )] );
kevman 0:38ceb79fef03 118 }
kevman 0:38ceb79fef03 119
kevman 0:38ceb79fef03 120 ctx->x = x;
kevman 0:38ceb79fef03 121 ctx->y = y;
kevman 0:38ceb79fef03 122
kevman 0:38ceb79fef03 123 return( 0 );
kevman 0:38ceb79fef03 124 }
kevman 0:38ceb79fef03 125
kevman 0:38ceb79fef03 126 #endif /* !MBEDTLS_ARC4_ALT */
kevman 0:38ceb79fef03 127
kevman 0:38ceb79fef03 128 #if defined(MBEDTLS_SELF_TEST)
kevman 0:38ceb79fef03 129 /*
kevman 0:38ceb79fef03 130 * ARC4 tests vectors as posted by Eric Rescorla in sep. 1994:
kevman 0:38ceb79fef03 131 *
kevman 0:38ceb79fef03 132 * http://groups.google.com/group/comp.security.misc/msg/10a300c9d21afca0
kevman 0:38ceb79fef03 133 */
kevman 0:38ceb79fef03 134 static const unsigned char arc4_test_key[3][8] =
kevman 0:38ceb79fef03 135 {
kevman 0:38ceb79fef03 136 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
kevman 0:38ceb79fef03 137 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
kevman 0:38ceb79fef03 138 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
kevman 0:38ceb79fef03 139 };
kevman 0:38ceb79fef03 140
kevman 0:38ceb79fef03 141 static const unsigned char arc4_test_pt[3][8] =
kevman 0:38ceb79fef03 142 {
kevman 0:38ceb79fef03 143 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
kevman 0:38ceb79fef03 144 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
kevman 0:38ceb79fef03 145 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
kevman 0:38ceb79fef03 146 };
kevman 0:38ceb79fef03 147
kevman 0:38ceb79fef03 148 static const unsigned char arc4_test_ct[3][8] =
kevman 0:38ceb79fef03 149 {
kevman 0:38ceb79fef03 150 { 0x75, 0xB7, 0x87, 0x80, 0x99, 0xE0, 0xC5, 0x96 },
kevman 0:38ceb79fef03 151 { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 },
kevman 0:38ceb79fef03 152 { 0xDE, 0x18, 0x89, 0x41, 0xA3, 0x37, 0x5D, 0x3A }
kevman 0:38ceb79fef03 153 };
kevman 0:38ceb79fef03 154
kevman 0:38ceb79fef03 155 /*
kevman 0:38ceb79fef03 156 * Checkup routine
kevman 0:38ceb79fef03 157 */
kevman 0:38ceb79fef03 158 int mbedtls_arc4_self_test( int verbose )
kevman 0:38ceb79fef03 159 {
kevman 0:38ceb79fef03 160 int i, ret = 0;
kevman 0:38ceb79fef03 161 unsigned char ibuf[8];
kevman 0:38ceb79fef03 162 unsigned char obuf[8];
kevman 0:38ceb79fef03 163 mbedtls_arc4_context ctx;
kevman 0:38ceb79fef03 164
kevman 0:38ceb79fef03 165 mbedtls_arc4_init( &ctx );
kevman 0:38ceb79fef03 166
kevman 0:38ceb79fef03 167 for( i = 0; i < 3; i++ )
kevman 0:38ceb79fef03 168 {
kevman 0:38ceb79fef03 169 if( verbose != 0 )
kevman 0:38ceb79fef03 170 mbedtls_printf( " ARC4 test #%d: ", i + 1 );
kevman 0:38ceb79fef03 171
kevman 0:38ceb79fef03 172 memcpy( ibuf, arc4_test_pt[i], 8 );
kevman 0:38ceb79fef03 173
kevman 0:38ceb79fef03 174 mbedtls_arc4_setup( &ctx, arc4_test_key[i], 8 );
kevman 0:38ceb79fef03 175 mbedtls_arc4_crypt( &ctx, 8, ibuf, obuf );
kevman 0:38ceb79fef03 176
kevman 0:38ceb79fef03 177 if( memcmp( obuf, arc4_test_ct[i], 8 ) != 0 )
kevman 0:38ceb79fef03 178 {
kevman 0:38ceb79fef03 179 if( verbose != 0 )
kevman 0:38ceb79fef03 180 mbedtls_printf( "failed\n" );
kevman 0:38ceb79fef03 181
kevman 0:38ceb79fef03 182 ret = 1;
kevman 0:38ceb79fef03 183 goto exit;
kevman 0:38ceb79fef03 184 }
kevman 0:38ceb79fef03 185
kevman 0:38ceb79fef03 186 if( verbose != 0 )
kevman 0:38ceb79fef03 187 mbedtls_printf( "passed\n" );
kevman 0:38ceb79fef03 188 }
kevman 0:38ceb79fef03 189
kevman 0:38ceb79fef03 190 if( verbose != 0 )
kevman 0:38ceb79fef03 191 mbedtls_printf( "\n" );
kevman 0:38ceb79fef03 192
kevman 0:38ceb79fef03 193 exit:
kevman 0:38ceb79fef03 194 mbedtls_arc4_free( &ctx );
kevman 0:38ceb79fef03 195
kevman 0:38ceb79fef03 196 return( ret );
kevman 0:38ceb79fef03 197 }
kevman 0:38ceb79fef03 198
kevman 0:38ceb79fef03 199 #endif /* MBEDTLS_SELF_TEST */
kevman 0:38ceb79fef03 200
kevman 0:38ceb79fef03 201 #endif /* MBEDTLS_ARC4_C */