strongswan/src/libstrongswan/plugins/md4/md4_hasher.c

360 lines
9.1 KiB
C

/*
* Copyright (C) 2005-2006 Martin Willi
* Copyright (C) 2005 Jan Hutter
* Hochschule fuer Technik Rapperswil
* Copyright (C) 1990-1992, RSA Data Security, Inc. Created 1990.
* All rights reserved.
*
* Derived from the RSA Data Security, Inc. MD4 Message-Digest Algorithm.
* Ported to fulfill hasher_t interface.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* $Id: md4_hasher.c 3488 2008-02-21 15:10:02Z martin $
*/
#include <string.h>
#include "md4_hasher.h"
/*
* Constants for MD4Transform routine.
*/
#define S11 3
#define S12 7
#define S13 11
#define S14 19
#define S21 3
#define S22 5
#define S23 9
#define S24 13
#define S31 3
#define S32 9
#define S33 11
#define S34 15
static u_int8_t PADDING[64] = {
0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/*
* F, G, H and I are basic MD4 functions.
*/
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
/*
* ROTATE_LEFT rotates x left n bits.
*/
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
/* FF, GG and HH are transformations for rounds 1, 2 and 3
* Rotation is separate from addition to prevent recomputation
*/
#define FF(a, b, c, d, x, s) { \
(a) += F ((b), (c), (d)) + (x); \
(a) = ROTATE_LEFT ((a), (s)); \
}
#define GG(a, b, c, d, x, s) { \
(a) += G ((b), (c), (d)) + (x) + (u_int32_t)0x5a827999; \
(a) = ROTATE_LEFT ((a), (s)); \
}
#define HH(a, b, c, d, x, s) { \
(a) += H ((b), (c), (d)) + (x) + (u_int32_t)0x6ed9eba1; \
(a) = ROTATE_LEFT ((a), (s)); \
}
typedef struct private_md4_hasher_t private_md4_hasher_t;
/**
* Private data structure with hasing context.
*/
struct private_md4_hasher_t {
/**
* Public interface for this hasher.
*/
md4_hasher_t public;
/*
* State of the hasher.
*/
u_int32_t state[4];
u_int32_t count[2];
u_int8_t buffer[64];
};
#if BYTE_ORDER != LITTLE_ENDIAN
/* Encodes input (u_int32_t) into output (u_int8_t). Assumes len is
* a multiple of 4.
*/
static void Encode (u_int8_t *output, u_int32_t *input, size_t len)
{
size_t i, j;
for (i = 0, j = 0; j < len; i++, j += 4)
{
output[j] = (u_int8_t)(input[i] & 0xff);
output[j+1] = (u_int8_t)((input[i] >> 8) & 0xff);
output[j+2] = (u_int8_t)((input[i] >> 16) & 0xff);
output[j+3] = (u_int8_t)((input[i] >> 24) & 0xff);
}
}
/* Decodes input (u_int8_t) into output (u_int32_t). Assumes len is
* a multiple of 4.
*/
static void Decode(u_int32_t *output, u_int8_t *input, size_t len)
{
size_t i, j;
for (i = 0, j = 0; j < len; i++, j += 4)
{
output[i] = ((u_int32_t)input[j]) | (((u_int32_t)input[j+1]) << 8) |
(((u_int32_t)input[j+2]) << 16) | (((u_int32_t)input[j+3]) << 24);
}
}
#elif BYTE_ORDER == LITTLE_ENDIAN
#define Encode memcpy
#define Decode memcpy
#endif
/*
* MD4 basic transformation. Transforms state based on block.
*/
static void MD4Transform(u_int32_t state[4], u_int8_t block[64])
{
u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
Decode(x, block, 64);
/* Round 1 */
FF (a, b, c, d, x[ 0], S11); /* 1 */
FF (d, a, b, c, x[ 1], S12); /* 2 */
FF (c, d, a, b, x[ 2], S13); /* 3 */
FF (b, c, d, a, x[ 3], S14); /* 4 */
FF (a, b, c, d, x[ 4], S11); /* 5 */
FF (d, a, b, c, x[ 5], S12); /* 6 */
FF (c, d, a, b, x[ 6], S13); /* 7 */
FF (b, c, d, a, x[ 7], S14); /* 8 */
FF (a, b, c, d, x[ 8], S11); /* 9 */
FF (d, a, b, c, x[ 9], S12); /* 10 */
FF (c, d, a, b, x[10], S13); /* 11 */
FF (b, c, d, a, x[11], S14); /* 12 */
FF (a, b, c, d, x[12], S11); /* 13 */
FF (d, a, b, c, x[13], S12); /* 14 */
FF (c, d, a, b, x[14], S13); /* 15 */
FF (b, c, d, a, x[15], S14); /* 16 */
/* Round 2 */
GG (a, b, c, d, x[ 0], S21); /* 17 */
GG (d, a, b, c, x[ 4], S22); /* 18 */
GG (c, d, a, b, x[ 8], S23); /* 19 */
GG (b, c, d, a, x[12], S24); /* 20 */
GG (a, b, c, d, x[ 1], S21); /* 21 */
GG (d, a, b, c, x[ 5], S22); /* 22 */
GG (c, d, a, b, x[ 9], S23); /* 23 */
GG (b, c, d, a, x[13], S24); /* 24 */
GG (a, b, c, d, x[ 2], S21); /* 25 */
GG (d, a, b, c, x[ 6], S22); /* 26 */
GG (c, d, a, b, x[10], S23); /* 27 */
GG (b, c, d, a, x[14], S24); /* 28 */
GG (a, b, c, d, x[ 3], S21); /* 29 */
GG (d, a, b, c, x[ 7], S22); /* 30 */
GG (c, d, a, b, x[11], S23); /* 31 */
GG (b, c, d, a, x[15], S24); /* 32 */
/* Round 3 */
HH (a, b, c, d, x[ 0], S31); /* 33 */
HH (d, a, b, c, x[ 8], S32); /* 34 */
HH (c, d, a, b, x[ 4], S33); /* 35 */
HH (b, c, d, a, x[12], S34); /* 36 */
HH (a, b, c, d, x[ 2], S31); /* 37 */
HH (d, a, b, c, x[10], S32); /* 38 */
HH (c, d, a, b, x[ 6], S33); /* 39 */
HH (b, c, d, a, x[14], S34); /* 40 */
HH (a, b, c, d, x[ 1], S31); /* 41 */
HH (d, a, b, c, x[ 9], S32); /* 42 */
HH (c, d, a, b, x[ 5], S33); /* 43 */
HH (b, c, d, a, x[13], S34); /* 44 */
HH (a, b, c, d, x[ 3], S31); /* 45 */
HH (d, a, b, c, x[11], S32); /* 46 */
HH (c, d, a, b, x[ 7], S33); /* 47 */
HH (b, c, d, a, x[15], S34); /* 48 */
state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;
}
/* MD4 block update operation. Continues an MD4 message-digest
* operation, processing another message block, and updating the
* context.
*/
static void MD4Update(private_md4_hasher_t *this, u_int8_t *input, size_t inputLen)
{
u_int32_t i;
size_t index, partLen;
/* Compute number of bytes mod 64 */
index = (u_int8_t)((this->count[0] >> 3) & 0x3F);
/* Update number of bits */
if ((this->count[0] += (inputLen << 3)) < (inputLen << 3))
{
this->count[1]++;
}
this->count[1] += (inputLen >> 29);
partLen = 64 - index;
/* Transform as many times as possible. */
if (inputLen >= partLen)
{
memcpy(&this->buffer[index], input, partLen);
MD4Transform (this->state, this->buffer);
for (i = partLen; i + 63 < inputLen; i += 64)
{
MD4Transform (this->state, &input[i]);
}
index = 0;
}
else
{
i = 0;
}
/* Buffer remaining input */
memcpy(&this->buffer[index], &input[i], inputLen-i);
}
/* MD4 finalization. Ends an MD4 message-digest operation, writing the
* the message digest and zeroizing the context.
*/
static void MD4Final (private_md4_hasher_t *this, u_int8_t digest[16])
{
u_int8_t bits[8];
size_t index, padLen;
/* Save number of bits */
Encode (bits, this->count, 8);
/* Pad out to 56 mod 64. */
index = (size_t)((this->count[0] >> 3) & 0x3f);
padLen = (index < 56) ? (56 - index) : (120 - index);
MD4Update (this, PADDING, padLen);
/* Append length (before padding) */
MD4Update (this, bits, 8);
if (digest != NULL) /* Bill Simpson's padding */
{
/* store state in digest */
Encode (digest, this->state, 16);
}
}
/**
* Implementation of hasher_t.get_hash.
*/
static void get_hash(private_md4_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
{
MD4Update(this, chunk.ptr, chunk.len);
if (buffer != NULL)
{
MD4Final(this, buffer);
this->public.hasher_interface.reset(&(this->public.hasher_interface));
}
}
/**
* Implementation of hasher_t.allocate_hash.
*/
static void allocate_hash(private_md4_hasher_t *this, chunk_t chunk, chunk_t *hash)
{
chunk_t allocated_hash;
MD4Update(this, chunk.ptr, chunk.len);
if (hash != NULL)
{
allocated_hash.ptr = malloc(HASH_SIZE_MD4);
allocated_hash.len = HASH_SIZE_MD4;
MD4Final(this, allocated_hash.ptr);
this->public.hasher_interface.reset(&(this->public.hasher_interface));
*hash = allocated_hash;
}
}
/**
* Implementation of hasher_t.get_hash_size.
*/
static size_t get_hash_size(private_md4_hasher_t *this)
{
return HASH_SIZE_MD4;
}
/**
* Implementation of hasher_t.reset.
*/
static void reset(private_md4_hasher_t *this)
{
this->state[0] = 0x67452301;
this->state[1] = 0xefcdab89;
this->state[2] = 0x98badcfe;
this->state[3] = 0x10325476;
this->count[0] = 0;
this->count[1] = 0;
}
/**
* Implementation of hasher_t.destroy.
*/
static void destroy(private_md4_hasher_t *this)
{
free(this);
}
/*
* Described in header.
*/
md4_hasher_t *md4_hasher_create(hash_algorithm_t algo)
{
private_md4_hasher_t *this;
if (algo != HASH_MD4)
{
return NULL;
}
this = malloc_thing(private_md4_hasher_t);
this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
/* initialize */
reset(this);
return &(this->public);
}