Nitin Shukla / LED_Demo

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Dependencies:   MAX44000 nexpaq_mdk

Fork of LED_Demo by Maxim nexpaq

mbd_os/features/mbedtls/src/arc4.c@7:3a65ef12ba31, 2016-11-04 (annotated)

Committer:
nitsshukla
Date:
Fri Nov 04 12:06:04 2016 +0000
Revision:
7:3a65ef12ba31
Parent:
1:55a6170b404f 
kghj;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
nexpaq 1:55a6170b404f 1 /*
nexpaq 1:55a6170b404f 2 * An implementation of the ARCFOUR algorithm
nexpaq 1:55a6170b404f 3 *
nexpaq 1:55a6170b404f 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
nexpaq 1:55a6170b404f 5 * SPDX-License-Identifier: Apache-2.0
nexpaq 1:55a6170b404f 6 *
nexpaq 1:55a6170b404f 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
nexpaq 1:55a6170b404f 8 * not use this file except in compliance with the License.
nexpaq 1:55a6170b404f 9 * You may obtain a copy of the License at
nexpaq 1:55a6170b404f 10 *
nexpaq 1:55a6170b404f 11 * http://www.apache.org/licenses/LICENSE-2.0
nexpaq 1:55a6170b404f 12 *
nexpaq 1:55a6170b404f 13 * Unless required by applicable law or agreed to in writing, software
nexpaq 1:55a6170b404f 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
nexpaq 1:55a6170b404f 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
nexpaq 1:55a6170b404f 16 * See the License for the specific language governing permissions and
nexpaq 1:55a6170b404f 17 * limitations under the License.
nexpaq 1:55a6170b404f 18 *
nexpaq 1:55a6170b404f 19 * This file is part of mbed TLS (https://tls.mbed.org)
nexpaq 1:55a6170b404f 20 */
nexpaq 1:55a6170b404f 21 /*
nexpaq 1:55a6170b404f 22 * The ARCFOUR algorithm was publicly disclosed on 94/09.
nexpaq 1:55a6170b404f 23 *
nexpaq 1:55a6170b404f 24 * http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0
nexpaq 1:55a6170b404f 25 */
nexpaq 1:55a6170b404f 26
nexpaq 1:55a6170b404f 27 #if !defined(MBEDTLS_CONFIG_FILE)
nexpaq 1:55a6170b404f 28 #include "mbedtls/config.h"
nexpaq 1:55a6170b404f 29 #else
nexpaq 1:55a6170b404f 30 #include MBEDTLS_CONFIG_FILE
nexpaq 1:55a6170b404f 31 #endif
nexpaq 1:55a6170b404f 32
nexpaq 1:55a6170b404f 33 #if defined(MBEDTLS_ARC4_C)
nexpaq 1:55a6170b404f 34
nexpaq 1:55a6170b404f 35 #include "mbedtls/arc4.h"
nexpaq 1:55a6170b404f 36
nexpaq 1:55a6170b404f 37 #include <string.h>
nexpaq 1:55a6170b404f 38
nexpaq 1:55a6170b404f 39 #if defined(MBEDTLS_SELF_TEST)
nexpaq 1:55a6170b404f 40 #if defined(MBEDTLS_PLATFORM_C)
nexpaq 1:55a6170b404f 41 #include "mbedtls/platform.h"
nexpaq 1:55a6170b404f 42 #else
nexpaq 1:55a6170b404f 43 #include <stdio.h>
nexpaq 1:55a6170b404f 44 #define mbedtls_printf printf
nexpaq 1:55a6170b404f 45 #endif /* MBEDTLS_PLATFORM_C */
nexpaq 1:55a6170b404f 46 #endif /* MBEDTLS_SELF_TEST */
nexpaq 1:55a6170b404f 47
nexpaq 1:55a6170b404f 48 #if !defined(MBEDTLS_ARC4_ALT)
nexpaq 1:55a6170b404f 49
nexpaq 1:55a6170b404f 50 /* Implementation that should never be optimized out by the compiler */
nexpaq 1:55a6170b404f 51 static void mbedtls_zeroize( void *v, size_t n ) {
nexpaq 1:55a6170b404f 52 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
nexpaq 1:55a6170b404f 53 }
nexpaq 1:55a6170b404f 54
nexpaq 1:55a6170b404f 55 void mbedtls_arc4_init( mbedtls_arc4_context *ctx )
nexpaq 1:55a6170b404f 56 {
nexpaq 1:55a6170b404f 57 memset( ctx, 0, sizeof( mbedtls_arc4_context ) );
nexpaq 1:55a6170b404f 58 }
nexpaq 1:55a6170b404f 59
nexpaq 1:55a6170b404f 60 void mbedtls_arc4_free( mbedtls_arc4_context *ctx )
nexpaq 1:55a6170b404f 61 {
nexpaq 1:55a6170b404f 62 if( ctx == NULL )
nexpaq 1:55a6170b404f 63 return;
nexpaq 1:55a6170b404f 64
nexpaq 1:55a6170b404f 65 mbedtls_zeroize( ctx, sizeof( mbedtls_arc4_context ) );
nexpaq 1:55a6170b404f 66 }
nexpaq 1:55a6170b404f 67
nexpaq 1:55a6170b404f 68 /*
nexpaq 1:55a6170b404f 69 * ARC4 key schedule
nexpaq 1:55a6170b404f 70 */
nexpaq 1:55a6170b404f 71 void mbedtls_arc4_setup( mbedtls_arc4_context *ctx, const unsigned char *key,
nexpaq 1:55a6170b404f 72 unsigned int keylen )
nexpaq 1:55a6170b404f 73 {
nexpaq 1:55a6170b404f 74 int i, j, a;
nexpaq 1:55a6170b404f 75 unsigned int k;
nexpaq 1:55a6170b404f 76 unsigned char *m;
nexpaq 1:55a6170b404f 77
nexpaq 1:55a6170b404f 78 ctx->x = 0;
nexpaq 1:55a6170b404f 79 ctx->y = 0;
nexpaq 1:55a6170b404f 80 m = ctx->m;
nexpaq 1:55a6170b404f 81
nexpaq 1:55a6170b404f 82 for( i = 0; i < 256; i++ )
nexpaq 1:55a6170b404f 83 m[i] = (unsigned char) i;
nexpaq 1:55a6170b404f 84
nexpaq 1:55a6170b404f 85 j = k = 0;
nexpaq 1:55a6170b404f 86
nexpaq 1:55a6170b404f 87 for( i = 0; i < 256; i++, k++ )
nexpaq 1:55a6170b404f 88 {
nexpaq 1:55a6170b404f 89 if( k >= keylen ) k = 0;
nexpaq 1:55a6170b404f 90
nexpaq 1:55a6170b404f 91 a = m[i];
nexpaq 1:55a6170b404f 92 j = ( j + a + key[k] ) & 0xFF;
nexpaq 1:55a6170b404f 93 m[i] = m[j];
nexpaq 1:55a6170b404f 94 m[j] = (unsigned char) a;
nexpaq 1:55a6170b404f 95 }
nexpaq 1:55a6170b404f 96 }
nexpaq 1:55a6170b404f 97
nexpaq 1:55a6170b404f 98 /*
nexpaq 1:55a6170b404f 99 * ARC4 cipher function
nexpaq 1:55a6170b404f 100 */
nexpaq 1:55a6170b404f 101 int mbedtls_arc4_crypt( mbedtls_arc4_context *ctx, size_t length, const unsigned char *input,
nexpaq 1:55a6170b404f 102 unsigned char *output )
nexpaq 1:55a6170b404f 103 {
nexpaq 1:55a6170b404f 104 int x, y, a, b;
nexpaq 1:55a6170b404f 105 size_t i;
nexpaq 1:55a6170b404f 106 unsigned char *m;
nexpaq 1:55a6170b404f 107
nexpaq 1:55a6170b404f 108 x = ctx->x;
nexpaq 1:55a6170b404f 109 y = ctx->y;
nexpaq 1:55a6170b404f 110 m = ctx->m;
nexpaq 1:55a6170b404f 111
nexpaq 1:55a6170b404f 112 for( i = 0; i < length; i++ )
nexpaq 1:55a6170b404f 113 {
nexpaq 1:55a6170b404f 114 x = ( x + 1 ) & 0xFF; a = m[x];
nexpaq 1:55a6170b404f 115 y = ( y + a ) & 0xFF; b = m[y];
nexpaq 1:55a6170b404f 116
nexpaq 1:55a6170b404f 117 m[x] = (unsigned char) b;
nexpaq 1:55a6170b404f 118 m[y] = (unsigned char) a;
nexpaq 1:55a6170b404f 119
nexpaq 1:55a6170b404f 120 output[i] = (unsigned char)
nexpaq 1:55a6170b404f 121 ( input[i] ^ m[(unsigned char)( a + b )] );
nexpaq 1:55a6170b404f 122 }
nexpaq 1:55a6170b404f 123
nexpaq 1:55a6170b404f 124 ctx->x = x;
nexpaq 1:55a6170b404f 125 ctx->y = y;
nexpaq 1:55a6170b404f 126
nexpaq 1:55a6170b404f 127 return( 0 );
nexpaq 1:55a6170b404f 128 }
nexpaq 1:55a6170b404f 129
nexpaq 1:55a6170b404f 130 #endif /* !MBEDTLS_ARC4_ALT */
nexpaq 1:55a6170b404f 131
nexpaq 1:55a6170b404f 132 #if defined(MBEDTLS_SELF_TEST)
nexpaq 1:55a6170b404f 133 /*
nexpaq 1:55a6170b404f 134 * ARC4 tests vectors as posted by Eric Rescorla in sep. 1994:
nexpaq 1:55a6170b404f 135 *
nexpaq 1:55a6170b404f 136 * http://groups.google.com/group/comp.security.misc/msg/10a300c9d21afca0
nexpaq 1:55a6170b404f 137 */
nexpaq 1:55a6170b404f 138 static const unsigned char arc4_test_key[3][8] =
nexpaq 1:55a6170b404f 139 {
nexpaq 1:55a6170b404f 140 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
nexpaq 1:55a6170b404f 141 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
nexpaq 1:55a6170b404f 142 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
nexpaq 1:55a6170b404f 143 };
nexpaq 1:55a6170b404f 144
nexpaq 1:55a6170b404f 145 static const unsigned char arc4_test_pt[3][8] =
nexpaq 1:55a6170b404f 146 {
nexpaq 1:55a6170b404f 147 { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF },
nexpaq 1:55a6170b404f 148 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
nexpaq 1:55a6170b404f 149 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
nexpaq 1:55a6170b404f 150 };
nexpaq 1:55a6170b404f 151
nexpaq 1:55a6170b404f 152 static const unsigned char arc4_test_ct[3][8] =
nexpaq 1:55a6170b404f 153 {
nexpaq 1:55a6170b404f 154 { 0x75, 0xB7, 0x87, 0x80, 0x99, 0xE0, 0xC5, 0x96 },
nexpaq 1:55a6170b404f 155 { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 },
nexpaq 1:55a6170b404f 156 { 0xDE, 0x18, 0x89, 0x41, 0xA3, 0x37, 0x5D, 0x3A }
nexpaq 1:55a6170b404f 157 };
nexpaq 1:55a6170b404f 158
nexpaq 1:55a6170b404f 159 /*
nexpaq 1:55a6170b404f 160 * Checkup routine
nexpaq 1:55a6170b404f 161 */
nexpaq 1:55a6170b404f 162 int mbedtls_arc4_self_test( int verbose )
nexpaq 1:55a6170b404f 163 {
nexpaq 1:55a6170b404f 164 int i, ret = 0;
nexpaq 1:55a6170b404f 165 unsigned char ibuf[8];
nexpaq 1:55a6170b404f 166 unsigned char obuf[8];
nexpaq 1:55a6170b404f 167 mbedtls_arc4_context ctx;
nexpaq 1:55a6170b404f 168
nexpaq 1:55a6170b404f 169 mbedtls_arc4_init( &ctx );
nexpaq 1:55a6170b404f 170
nexpaq 1:55a6170b404f 171 for( i = 0; i < 3; i++ )
nexpaq 1:55a6170b404f 172 {
nexpaq 1:55a6170b404f 173 if( verbose != 0 )
nexpaq 1:55a6170b404f 174 mbedtls_printf( " ARC4 test #%d: ", i + 1 );
nexpaq 1:55a6170b404f 175
nexpaq 1:55a6170b404f 176 memcpy( ibuf, arc4_test_pt[i], 8 );
nexpaq 1:55a6170b404f 177
nexpaq 1:55a6170b404f 178 mbedtls_arc4_setup( &ctx, arc4_test_key[i], 8 );
nexpaq 1:55a6170b404f 179 mbedtls_arc4_crypt( &ctx, 8, ibuf, obuf );
nexpaq 1:55a6170b404f 180
nexpaq 1:55a6170b404f 181 if( memcmp( obuf, arc4_test_ct[i], 8 ) != 0 )
nexpaq 1:55a6170b404f 182 {
nexpaq 1:55a6170b404f 183 if( verbose != 0 )
nexpaq 1:55a6170b404f 184 mbedtls_printf( "failed\n" );
nexpaq 1:55a6170b404f 185
nexpaq 1:55a6170b404f 186 ret = 1;
nexpaq 1:55a6170b404f 187 goto exit;
nexpaq 1:55a6170b404f 188 }
nexpaq 1:55a6170b404f 189
nexpaq 1:55a6170b404f 190 if( verbose != 0 )
nexpaq 1:55a6170b404f 191 mbedtls_printf( "passed\n" );
nexpaq 1:55a6170b404f 192 }
nexpaq 1:55a6170b404f 193
nexpaq 1:55a6170b404f 194 if( verbose != 0 )
nexpaq 1:55a6170b404f 195 mbedtls_printf( "\n" );
nexpaq 1:55a6170b404f 196
nexpaq 1:55a6170b404f 197 exit:
nexpaq 1:55a6170b404f 198 mbedtls_arc4_free( &ctx );
nexpaq 1:55a6170b404f 199
nexpaq 1:55a6170b404f 200 return( ret );
nexpaq 1:55a6170b404f 201 }
nexpaq 1:55a6170b404f 202
nexpaq 1:55a6170b404f 203 #endif /* MBEDTLS_SELF_TEST */
nexpaq 1:55a6170b404f 204
nexpaq 1:55a6170b404f 205 #endif /* MBEDTLS_ARC4_C */