+++ /dev/null
-/* -*-c-*-
- *
- * $Id: serpent.c,v 1.2 2004/04/08 01:36:15 mdw Exp $
- *
- * The Serpent block cipher
- *
- * (c) 2000 Straylight/Edgeware
- */
-
-/*----- Licensing notice --------------------------------------------------*
- *
- * This file is part of Catacomb.
- *
- * Catacomb is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Library General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * Catacomb 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 Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with Catacomb; if not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA.
- */
-
-/*----- Header files ------------------------------------------------------*/
-
-#include <assert.h>
-#include <stdio.h>
-
-#include <mLib/bits.h>
-
-#include "blkc.h"
-#include "gcipher.h"
-#include "serpent.h"
-#include "serpent-sbox.h"
-
-/*----- Global variables --------------------------------------------------*/
-
-const octet serpent_keysz[] = { KSZ_RANGE, SERPENT_KEYSZ, 0, 32, 1 };
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @serpent_init@ --- *
- *
- * Arguments: @serpent_ctx *k@ = pointer to context block to initialize
- * @const void *buf@ = pointer to input buffer
- * @size_t sz@ = size of input buffer
- *
- * Returns: ---
- *
- * Use: Initializes a Serpent context. The key may be any length of
- * up to 32 bytes (256 bits).
- */
-
-void serpent_init(serpent_ctx *k, const void *buf, size_t sz)
-{
- uint32 a;
- unsigned b;
- const octet *p, *q;
- size_t i;
- uint32 pk[8 + 132];
-
- KSZ_ASSERT(serpent, sz);
-
- /* --- Read the key into the buffer --- */
-
- if (sz > 32)
- sz = 32;
- i = 0; p = buf; q = p + sz;
- a = 0; b = 0;
- while (p < q) {
- a |= (uint32)*p++ << b;
- b += 8;
- if (b == 32) {
- pk[i++] = a;
- a = 0; b = 0;
- }
- }
-
- /* --- Pad short keys --- */
-
- if (i < 8) {
- a |= 0x01 << b;
- b += 8;
- pk[i++] = a;
- for (; i < 8; i++)
- pk[i] = 0;
- }
-
- /* --- Expand the prekeys to fill the buffer --- */
-
- for (i = 8; i < 8 + 132; i++) {
- uint32 x = (pk[i - 8] ^ pk[i - 5] ^ pk[i - 3] ^ pk[i - 1] ^
- (i - 8) ^ 0x9e3779b9);
- k->k[i - 8] = pk[i] = ROL32(x, 11);
- }
-
- /* --- Now substitute everything --- */
-
- i = 0;
- goto midway;
- while (i < 132) {
-#define KSUB(r) do { \
- uint32 a, b, c, d; \
- a = k->k[i]; b = k->k[i + 1]; c = k->k[i + 2]; d = k->k[i + 3]; \
- S##r(a, b, c, d); \
- k->k[i] = a; k->k[i + 1] = b; k->k[i + 2] = c; k->k[i + 3] = d; \
- i += 4; \
-} while (0)
- KSUB(2); KSUB(1); KSUB(0); KSUB(7);
- KSUB(6); KSUB(5); KSUB(4);
- midway:
- KSUB(3);
-#undef KSUB
- }
-}
-
-/* --- @serpent_eblk@, @serpent_dblk@ --- *
- *
- * Arguments: @const serpent_ctx *k@ = pointer to key context
- * @const uint32 s[4]@ = pointer to source block
- * @uint32 d[4]@ = pointer to destination block
- *
- * Returns: ---
- *
- * Use: Low-level block encryption.
- */
-
-#define EROUND(a, b, c, d, r, k) do { \
- a ^= *k++; b ^= *k++; c ^= *k++; d ^= *k++; \
- S##r(a, b, c, d); \
- a = ROL32(a, 13); c = ROL32(c, 3); b ^= a ^ c; d ^= c ^ (a << 3); \
- b = ROL32(b, 1); d = ROL32(d, 7); a ^= b ^ d; c ^= d ^ (b << 7); \
- a = ROL32(a, 5); c = ROL32(c, 22); \
-} while (0)
-
-#define DROUND(a, b, c, d, r, k) do { \
- IS##r(a, b, c, d); \
- d ^= *--k; c ^= *--k; b ^= *--k; a ^= *--k; \
- a = ROR32(a, 5); c = ROR32(c, 22); a ^= b ^ d; c ^= d ^ (b << 7); \
- b = ROR32(b, 1); d = ROR32(d, 7); b ^= a ^ c; d ^= c ^ (a << 3); \
- a = ROR32(a, 13); c = ROR32(c, 3); \
-} while (0)
-
-void serpent_eblk(const serpent_ctx *k, const uint32 *s, uint32 *d)
-{
- uint32 aa = s[0], bb = s[1], cc = s[2], dd = s[3];
- const uint32 *kk = k->k;
-
- EROUND(aa, bb, cc, dd, 0, kk); EROUND(aa, bb, cc, dd, 1, kk);
- EROUND(aa, bb, cc, dd, 2, kk); EROUND(aa, bb, cc, dd, 3, kk);
- EROUND(aa, bb, cc, dd, 4, kk); EROUND(aa, bb, cc, dd, 5, kk);
- EROUND(aa, bb, cc, dd, 6, kk); EROUND(aa, bb, cc, dd, 7, kk);
-
- EROUND(aa, bb, cc, dd, 0, kk); EROUND(aa, bb, cc, dd, 1, kk);
- EROUND(aa, bb, cc, dd, 2, kk); EROUND(aa, bb, cc, dd, 3, kk);
- EROUND(aa, bb, cc, dd, 4, kk); EROUND(aa, bb, cc, dd, 5, kk);
- EROUND(aa, bb, cc, dd, 6, kk); EROUND(aa, bb, cc, dd, 7, kk);
-
- EROUND(aa, bb, cc, dd, 0, kk); EROUND(aa, bb, cc, dd, 1, kk);
- EROUND(aa, bb, cc, dd, 2, kk); EROUND(aa, bb, cc, dd, 3, kk);
- EROUND(aa, bb, cc, dd, 4, kk); EROUND(aa, bb, cc, dd, 5, kk);
- EROUND(aa, bb, cc, dd, 6, kk); EROUND(aa, bb, cc, dd, 7, kk);
-
- EROUND(aa, bb, cc, dd, 0, kk); EROUND(aa, bb, cc, dd, 1, kk);
- EROUND(aa, bb, cc, dd, 2, kk); EROUND(aa, bb, cc, dd, 3, kk);
- EROUND(aa, bb, cc, dd, 4, kk); EROUND(aa, bb, cc, dd, 5, kk);
- EROUND(aa, bb, cc, dd, 6, kk);
-
- aa ^= *kk++; bb ^= *kk++; cc ^= *kk++; dd ^= *kk++;
- S7(aa, bb, cc, dd);
- aa ^= *kk++; bb ^= *kk++; cc ^= *kk++; dd ^= *kk++;
- d[0] = aa; d[1] = bb; d[2] = cc; d[3] = dd;
-}
-
-void serpent_dblk(const serpent_ctx *k, const uint32 *s, uint32 *d)
-{
- uint32 aa = s[0], bb = s[1], cc = s[2], dd = s[3];
- const uint32 *kk = k->k + 132;
-
- dd ^= *--kk; cc ^= *--kk; bb ^= *--kk; aa ^= *--kk;
-
- DROUND(aa, bb, cc, dd, 7, kk); DROUND(aa, bb, cc, dd, 6, kk);
- DROUND(aa, bb, cc, dd, 5, kk); DROUND(aa, bb, cc, dd, 4, kk);
- DROUND(aa, bb, cc, dd, 3, kk); DROUND(aa, bb, cc, dd, 2, kk);
- DROUND(aa, bb, cc, dd, 1, kk); DROUND(aa, bb, cc, dd, 0, kk);
-
- DROUND(aa, bb, cc, dd, 7, kk); DROUND(aa, bb, cc, dd, 6, kk);
- DROUND(aa, bb, cc, dd, 5, kk); DROUND(aa, bb, cc, dd, 4, kk);
- DROUND(aa, bb, cc, dd, 3, kk); DROUND(aa, bb, cc, dd, 2, kk);
- DROUND(aa, bb, cc, dd, 1, kk); DROUND(aa, bb, cc, dd, 0, kk);
-
- DROUND(aa, bb, cc, dd, 7, kk); DROUND(aa, bb, cc, dd, 6, kk);
- DROUND(aa, bb, cc, dd, 5, kk); DROUND(aa, bb, cc, dd, 4, kk);
- DROUND(aa, bb, cc, dd, 3, kk); DROUND(aa, bb, cc, dd, 2, kk);
- DROUND(aa, bb, cc, dd, 1, kk); DROUND(aa, bb, cc, dd, 0, kk);
-
- DROUND(aa, bb, cc, dd, 7, kk); DROUND(aa, bb, cc, dd, 6, kk);
- DROUND(aa, bb, cc, dd, 5, kk); DROUND(aa, bb, cc, dd, 4, kk);
- DROUND(aa, bb, cc, dd, 3, kk); DROUND(aa, bb, cc, dd, 2, kk);
- DROUND(aa, bb, cc, dd, 1, kk);
-
- IS0(aa, bb, cc, dd);
- dd ^= *--kk; cc ^= *--kk; bb ^= *--kk; aa ^= *--kk;
- d[0] = aa; d[1] = bb; d[2] = cc; d[3] = dd;
-}
-
-BLKC_TEST(SERPENT, serpent)
-
-/*----- That's all, folks -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff