/*
* MD4 (RFC-1320) message digest.
* Modified from MD5 code by Andrey Panin <pazke@donpac.ru>
*
* Written by Solar Designer <solar@openwall.com> in 2001, and placed in
* the public domain. There's absolutely no warranty.
*
* This differs from Colin Plumb's older public domain implementation in
* that no 32-bit integer data type is required, there's no compile-time
* endianness configuration.
* The primary goals are portability and ease of use.
*
* This implementation is meant to be fast, but not as fast as possible.
* Some known optimizations are not included to reduce source code size
* and avoid compile-time configuration.
*/
#include "crypt-port.h"
#include "alg-md4.h"
#include "byteorder.h"
#if INCLUDE_nthash
/*
* The basic MD4 functions.
*/
#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
/*
* The MD4 transformation for all four rounds.
*/
#define STEP(f, a, b, c, d, x, s) \
(a) += f((b), (c), (d)) + (x); \
(a) = ((a) << (s)) | ((a) >> (32 - (s)))
/*
* SET reads 4 input bytes in little-endian byte order and stores them
* in a properly aligned word in host byte order.
*
* The check for little-endian architectures which tolerate unaligned
* memory accesses is just an optimization. Nothing will break if it
* doesn't work.
*/
#define SET(n) \
(ctx->block[(n)] = le32_to_cpu (&ptr[(n) * 4]))
#define GET(n) \
(ctx->block[(n)])
/*
* This processes one or more 64-byte data blocks, but does NOT update
* the bit counters. There're no alignment requirements.
*/
static const unsigned char *
body (struct md4_ctx *ctx, const unsigned char *data, size_t size)
{
const unsigned char *ptr;
uint32_t a, b, c, d;
uint32_t saved_a, saved_b, saved_c, saved_d;
ptr = data;
a = ctx->a;
b = ctx->b;
c = ctx->c;
d = ctx->d;
do
{
saved_a = a;
saved_b = b;
saved_c = c;
saved_d = d;
/* Round 1 */
STEP(F, a, b, c, d, SET( 0), 3);
STEP(F, d, a, b, c, SET( 1), 7);
STEP(F, c, d, a, b, SET( 2), 11);
STEP(F, b, c, d, a, SET( 3), 19);
STEP(F, a, b, c, d, SET( 4), 3);
STEP(F, d, a, b, c, SET( 5), 7);
STEP(F, c, d, a, b, SET( 6), 11);
STEP(F, b, c, d, a, SET( 7), 19);
STEP(F, a, b, c, d, SET( 8), 3);
STEP(F, d, a, b, c, SET( 9), 7);
STEP(F, c, d, a, b, SET(10), 11);
STEP(F, b, c, d, a, SET(11), 19);
STEP(F, a, b, c, d, SET(12), 3);
STEP(F, d, a, b, c, SET(13), 7);
STEP(F, c, d, a, b, SET(14), 11);
STEP(F, b, c, d, a, SET(15), 19);
/* Round 2 */
STEP(G, a, b, c, d, GET( 0) + 0x5A827999, 3);
STEP(G, d, a, b, c, GET( 4) + 0x5A827999, 5);
STEP(G, c, d, a, b, GET( 8) + 0x5A827999, 9);
STEP(G, b, c, d, a, GET(12) + 0x5A827999, 13);
STEP(G, a, b, c, d, GET( 1) + 0x5A827999, 3);
STEP(G, d, a, b, c, GET( 5) + 0x5A827999, 5);
STEP(G, c, d, a, b, GET( 9) + 0x5A827999, 9);
STEP(G, b, c, d, a, GET(13) + 0x5A827999, 13);
STEP(G, a, b, c, d, GET( 2) + 0x5A827999, 3);
STEP(G, d, a, b, c, GET( 6) + 0x5A827999, 5);
STEP(G, c, d, a, b, GET(10) + 0x5A827999, 9);
STEP(G, b, c, d, a, GET(14) + 0x5A827999, 13);
STEP(G, a, b, c, d, GET( 3) + 0x5A827999, 3);
STEP(G, d, a, b, c, GET( 7) + 0x5A827999, 5);
STEP(G, c, d, a, b, GET(11) + 0x5A827999, 9);
STEP(G, b, c, d, a, GET(15) + 0x5A827999, 13);
/* Round 3 */
STEP(H, a, b, c, d, GET( 0) + 0x6ED9EBA1, 3);
STEP(H, d, a, b, c, GET( 8) + 0x6ED9EBA1, 9);
STEP(H, c, d, a, b, GET( 4) + 0x6ED9EBA1, 11);
STEP(H, b, c, d, a, GET(12) + 0x6ED9EBA1, 15);
STEP(H, a, b, c, d, GET( 2) + 0x6ED9EBA1, 3);
STEP(H, d, a, b, c, GET(10) + 0x6ED9EBA1, 9);
STEP(H, c, d, a, b, GET( 6) + 0x6ED9EBA1, 11);
STEP(H, b, c, d, a, GET(14) + 0x6ED9EBA1, 15);
STEP(H, a, b, c, d, GET( 1) + 0x6ED9EBA1, 3);
STEP(H, d, a, b, c, GET( 9) + 0x6ED9EBA1, 9);
STEP(H, c, d, a, b, GET( 5) + 0x6ED9EBA1, 11);
STEP(H, b, c, d, a, GET(13) + 0x6ED9EBA1, 15);
STEP(H, a, b, c, d, GET( 3) + 0x6ED9EBA1, 3);
STEP(H, d, a, b, c, GET(11) + 0x6ED9EBA1, 9);
STEP(H, c, d, a, b, GET( 7) + 0x6ED9EBA1, 11);
STEP(H, b, c, d, a, GET(15) + 0x6ED9EBA1, 15);
a += saved_a;
b += saved_b;
c += saved_c;
d += saved_d;
ptr += 64;
}
while (size -= 64);
ctx->a = a;
ctx->b = b;
ctx->c = c;
ctx->d = d;
return ptr;
}
/* Put result from CTX in first 16 bytes following RESBUF. The result
will be in little endian byte order. */
static void *
md4_read_ctx (struct md4_ctx *ctx, void *resbuf)
{
unsigned char *buf = resbuf;
cpu_to_le32 (buf + 0, ctx->a);
cpu_to_le32 (buf + 4, ctx->b);
cpu_to_le32 (buf + 8, ctx->c);
cpu_to_le32 (buf + 12, ctx->d);
XCRYPT_SECURE_MEMSET (ctx, sizeof(struct md4_ctx));
return resbuf;
}
void
md4_init_ctx (struct md4_ctx *ctx)
{
ctx->a = 0x67452301;
ctx->b = 0xefcdab89;
ctx->c = 0x98badcfe;
ctx->d = 0x10325476;
ctx->lo = 0;
ctx->hi = 0;
}
void
md4_process_bytes (const void *buffer, struct md4_ctx *ctx, size_t size)
{
uint32_t saved_lo;
size_t used, free;
saved_lo = ctx->lo;
if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
ctx->hi++;
ctx->hi += (uint32_t)(size >> 29);
used = saved_lo & 0x3f;
if (used)
{
free = 64 - used;
if (size < free)
{
memcpy(&ctx->buffer[used], buffer, size);
return;
}
memcpy(&ctx->buffer[used], buffer, free);
buffer = (const unsigned char *) buffer + free;
size -= free;
body(ctx, ctx->buffer, 64);
}
if (size >= 64)
{
buffer = body(ctx, buffer, size & ~(uint32_t)0x3f);
size &= 0x3f;
}
memcpy(ctx->buffer, buffer, size);
}
void *
md4_finish_ctx (struct md4_ctx *ctx, void *resbuf)
{
size_t used, free;
used = ctx->lo & 0x3f;
ctx->buffer[used++] = 0x80;
free = 64 - used;
if (free < 8)
{
XCRYPT_SECURE_MEMSET (&ctx->buffer[used], free);
body(ctx, ctx->buffer, 64);
used = 0;
free = 64;
}
XCRYPT_SECURE_MEMSET (&ctx->buffer[used], free - 8);
ctx->lo <<= 3;
ctx->buffer[56] = (unsigned char)((ctx->lo) & 0xff);
ctx->buffer[57] = (unsigned char)((ctx->lo >> 8) & 0xff);
ctx->buffer[58] = (unsigned char)((ctx->lo >> 16) & 0xff);
ctx->buffer[59] = (unsigned char)((ctx->lo >> 24) & 0xff);
ctx->buffer[60] = (unsigned char)((ctx->hi) & 0xff);
ctx->buffer[61] = (unsigned char)((ctx->hi >> 8) & 0xff);
ctx->buffer[62] = (unsigned char)((ctx->hi >> 16) & 0xff);
ctx->buffer[63] = (unsigned char)((ctx->hi >> 24) & 0xff);
body(ctx, ctx->buffer, 64);
return md4_read_ctx (ctx, resbuf);
}
#endif