diff options
Diffstat (limited to 'lib/mbedtls-2.27.0/library/arc4.c')
| -rw-r--r-- | lib/mbedtls-2.27.0/library/arc4.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/lib/mbedtls-2.27.0/library/arc4.c b/lib/mbedtls-2.27.0/library/arc4.c new file mode 100644 index 0000000..b34dc5e --- /dev/null +++ b/lib/mbedtls-2.27.0/library/arc4.c @@ -0,0 +1,195 @@ +/* + * An implementation of the ARCFOUR algorithm + * + * 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. + */ +/* + * The ARCFOUR algorithm was publicly disclosed on 94/09. + * + * http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0 + */ + +#include "common.h" + +#if defined(MBEDTLS_ARC4_C) + +#include "mbedtls/arc4.h" +#include "mbedtls/platform_util.h" + +#include <string.h> + +#if defined(MBEDTLS_SELF_TEST) +#if defined(MBEDTLS_PLATFORM_C) +#include "mbedtls/platform.h" +#else +#include <stdio.h> +#define mbedtls_printf printf +#endif /* MBEDTLS_PLATFORM_C */ +#endif /* MBEDTLS_SELF_TEST */ + +#if !defined(MBEDTLS_ARC4_ALT) + +void mbedtls_arc4_init( mbedtls_arc4_context *ctx ) +{ + memset( ctx, 0, sizeof( mbedtls_arc4_context ) ); +} + +void mbedtls_arc4_free( mbedtls_arc4_context *ctx ) +{ + if( ctx == NULL ) + return; + + mbedtls_platform_zeroize( ctx, sizeof( mbedtls_arc4_context ) ); +} + +/* + * ARC4 key schedule + */ +void mbedtls_arc4_setup( mbedtls_arc4_context *ctx, const unsigned char *key, + unsigned int keylen ) +{ + int i, j, a; + unsigned int k; + unsigned char *m; + + ctx->x = 0; + ctx->y = 0; + m = ctx->m; + + for( i = 0; i < 256; i++ ) + m[i] = (unsigned char) i; + + j = k = 0; + + for( i = 0; i < 256; i++, k++ ) + { + if( k >= keylen ) k = 0; + + a = m[i]; + j = ( j + a + key[k] ) & 0xFF; + m[i] = m[j]; + m[j] = (unsigned char) a; + } +} + +/* + * ARC4 cipher function + */ +int mbedtls_arc4_crypt( mbedtls_arc4_context *ctx, size_t length, const unsigned char *input, + unsigned char *output ) +{ + int x, y, a, b; + size_t i; + unsigned char *m; + + x = ctx->x; + y = ctx->y; + m = ctx->m; + + for( i = 0; i < length; i++ ) + { + x = ( x + 1 ) & 0xFF; a = m[x]; + y = ( y + a ) & 0xFF; b = m[y]; + + m[x] = (unsigned char) b; + m[y] = (unsigned char) a; + + output[i] = (unsigned char) + ( input[i] ^ m[(unsigned char)( a + b )] ); + } + + ctx->x = x; + ctx->y = y; + + return( 0 ); +} + +#endif /* !MBEDTLS_ARC4_ALT */ + +#if defined(MBEDTLS_SELF_TEST) +/* + * ARC4 tests vectors as posted by Eric Rescorla in sep. 1994: + * + * http://groups.google.com/group/comp.security.misc/msg/10a300c9d21afca0 + */ +static const unsigned char arc4_test_key[3][8] = +{ + { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF }, + { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } +}; + +static const unsigned char arc4_test_pt[3][8] = +{ + { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } +}; + +static const unsigned char arc4_test_ct[3][8] = +{ + { 0x75, 0xB7, 0x87, 0x80, 0x99, 0xE0, 0xC5, 0x96 }, + { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 }, + { 0xDE, 0x18, 0x89, 0x41, 0xA3, 0x37, 0x5D, 0x3A } +}; + +/* + * Checkup routine + */ +int mbedtls_arc4_self_test( int verbose ) +{ + int i, ret = 0; + unsigned char ibuf[8]; + unsigned char obuf[8]; + mbedtls_arc4_context ctx; + + mbedtls_arc4_init( &ctx ); + + for( i = 0; i < 3; i++ ) + { + if( verbose != 0 ) + mbedtls_printf( " ARC4 test #%d: ", i + 1 ); + + memcpy( ibuf, arc4_test_pt[i], 8 ); + + mbedtls_arc4_setup( &ctx, arc4_test_key[i], 8 ); + mbedtls_arc4_crypt( &ctx, 8, ibuf, obuf ); + + if( memcmp( obuf, arc4_test_ct[i], 8 ) != 0 ) + { + if( verbose != 0 ) + mbedtls_printf( "failed\n" ); + + ret = 1; + goto exit; + } + + if( verbose != 0 ) + mbedtls_printf( "passed\n" ); + } + + if( verbose != 0 ) + mbedtls_printf( "\n" ); + +exit: + mbedtls_arc4_free( &ctx ); + + return( ret ); +} + +#endif /* MBEDTLS_SELF_TEST */ + +#endif /* MBEDTLS_ARC4_C */ |