mbedtls/library/md2.c
Andres Amaya Garcia 6a54336897 Fix integer overflows in buffer bound checks
Fix potential integer overflows in the following functions:
  * mbedtls_md2_update() to be bypassed and cause
  * mbedtls_cipher_update()
  * mbedtls_ctr_drbg_reseed()
This overflows would mainly be exploitable in 32-bit systems and could
cause buffer bound checks to be bypassed.
2017-02-15 23:31:07 +02:00

288 lines
7.7 KiB
C

/*
* RFC 1115/1319 compliant MD2 implementation
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* 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.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
* The MD2 algorithm was designed by Ron Rivest in 1989.
*
* http://www.ietf.org/rfc/rfc1115.txt
* http://www.ietf.org/rfc/rfc1319.txt
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_MD2_C)
#include "mbedtls/md2.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_MD2_ALT)
/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize( void *v, size_t n ) {
volatile unsigned char *p = v; while( n-- ) *p++ = 0;
}
static const unsigned char PI_SUBST[256] =
{
0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36,
0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3,
0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C,
0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16,
0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12, 0xBE, 0x4E,
0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2,
0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E,
0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03, 0xFF, 0x19, 0x30, 0xB3,
0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56,
0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D,
0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65,
0xE6, 0x2D, 0xA8, 0x02, 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0,
0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C,
0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81,
0x4D, 0x52, 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA,
0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88,
0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE,
0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58,
0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99,
0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
};
void mbedtls_md2_init( mbedtls_md2_context *ctx )
{
memset( ctx, 0, sizeof( mbedtls_md2_context ) );
}
void mbedtls_md2_free( mbedtls_md2_context *ctx )
{
if( ctx == NULL )
return;
mbedtls_zeroize( ctx, sizeof( mbedtls_md2_context ) );
}
void mbedtls_md2_clone( mbedtls_md2_context *dst,
const mbedtls_md2_context *src )
{
*dst = *src;
}
/*
* MD2 context setup
*/
void mbedtls_md2_starts( mbedtls_md2_context *ctx )
{
memset( ctx->cksum, 0, 16 );
memset( ctx->state, 0, 46 );
memset( ctx->buffer, 0, 16 );
ctx->left = 0;
}
#if !defined(MBEDTLS_MD2_PROCESS_ALT)
void mbedtls_md2_process( mbedtls_md2_context *ctx )
{
int i, j;
unsigned char t = 0;
for( i = 0; i < 16; i++ )
{
ctx->state[i + 16] = ctx->buffer[i];
ctx->state[i + 32] =
(unsigned char)( ctx->buffer[i] ^ ctx->state[i]);
}
for( i = 0; i < 18; i++ )
{
for( j = 0; j < 48; j++ )
{
ctx->state[j] = (unsigned char)
( ctx->state[j] ^ PI_SUBST[t] );
t = ctx->state[j];
}
t = (unsigned char)( t + i );
}
t = ctx->cksum[15];
for( i = 0; i < 16; i++ )
{
ctx->cksum[i] = (unsigned char)
( ctx->cksum[i] ^ PI_SUBST[ctx->buffer[i] ^ t] );
t = ctx->cksum[i];
}
}
#endif /* !MBEDTLS_MD2_PROCESS_ALT */
/*
* MD2 process buffer
*/
void mbedtls_md2_update( mbedtls_md2_context *ctx, const unsigned char *input, size_t ilen )
{
size_t fill;
while( ilen > 0 )
{
if( ilen > 16 - ctx->left )
fill = 16 - ctx->left;
else
fill = ilen;
memcpy( ctx->buffer + ctx->left, input, fill );
ctx->left += fill;
input += fill;
ilen -= fill;
if( ctx->left == 16 )
{
ctx->left = 0;
mbedtls_md2_process( ctx );
}
}
}
/*
* MD2 final digest
*/
void mbedtls_md2_finish( mbedtls_md2_context *ctx, unsigned char output[16] )
{
size_t i;
unsigned char x;
x = (unsigned char)( 16 - ctx->left );
for( i = ctx->left; i < 16; i++ )
ctx->buffer[i] = x;
mbedtls_md2_process( ctx );
memcpy( ctx->buffer, ctx->cksum, 16 );
mbedtls_md2_process( ctx );
memcpy( output, ctx->state, 16 );
}
#endif /* !MBEDTLS_MD2_ALT */
/*
* output = MD2( input buffer )
*/
void mbedtls_md2( const unsigned char *input, size_t ilen, unsigned char output[16] )
{
mbedtls_md2_context ctx;
mbedtls_md2_init( &ctx );
mbedtls_md2_starts( &ctx );
mbedtls_md2_update( &ctx, input, ilen );
mbedtls_md2_finish( &ctx, output );
mbedtls_md2_free( &ctx );
}
#if defined(MBEDTLS_SELF_TEST)
/*
* RFC 1319 test vectors
*/
static const char md2_test_str[7][81] =
{
{ "" },
{ "a" },
{ "abc" },
{ "message digest" },
{ "abcdefghijklmnopqrstuvwxyz" },
{ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
{ "12345678901234567890123456789012345678901234567890123456789012" \
"345678901234567890" }
};
static const unsigned char md2_test_sum[7][16] =
{
{ 0x83, 0x50, 0xE5, 0xA3, 0xE2, 0x4C, 0x15, 0x3D,
0xF2, 0x27, 0x5C, 0x9F, 0x80, 0x69, 0x27, 0x73 },
{ 0x32, 0xEC, 0x01, 0xEC, 0x4A, 0x6D, 0xAC, 0x72,
0xC0, 0xAB, 0x96, 0xFB, 0x34, 0xC0, 0xB5, 0xD1 },
{ 0xDA, 0x85, 0x3B, 0x0D, 0x3F, 0x88, 0xD9, 0x9B,
0x30, 0x28, 0x3A, 0x69, 0xE6, 0xDE, 0xD6, 0xBB },
{ 0xAB, 0x4F, 0x49, 0x6B, 0xFB, 0x2A, 0x53, 0x0B,
0x21, 0x9F, 0xF3, 0x30, 0x31, 0xFE, 0x06, 0xB0 },
{ 0x4E, 0x8D, 0xDF, 0xF3, 0x65, 0x02, 0x92, 0xAB,
0x5A, 0x41, 0x08, 0xC3, 0xAA, 0x47, 0x94, 0x0B },
{ 0xDA, 0x33, 0xDE, 0xF2, 0xA4, 0x2D, 0xF1, 0x39,
0x75, 0x35, 0x28, 0x46, 0xC3, 0x03, 0x38, 0xCD },
{ 0xD5, 0x97, 0x6F, 0x79, 0xD8, 0x3D, 0x3A, 0x0D,
0xC9, 0x80, 0x6C, 0x3C, 0x66, 0xF3, 0xEF, 0xD8 }
};
/*
* Checkup routine
*/
int mbedtls_md2_self_test( int verbose )
{
int i;
unsigned char md2sum[16];
for( i = 0; i < 7; i++ )
{
if( verbose != 0 )
mbedtls_printf( " MD2 test #%d: ", i + 1 );
mbedtls_md2( (unsigned char *) md2_test_str[i],
strlen( md2_test_str[i] ), md2sum );
if( memcmp( md2sum, md2_test_sum[i], 16 ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
return( 1 );
}
if( verbose != 0 )
mbedtls_printf( "passed\n" );
}
if( verbose != 0 )
mbedtls_printf( "\n" );
return( 0 );
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_MD2_C */