+++ /dev/null
-/* -*-c-*-
- *
- * $Id: rc2.c,v 1.3 2004/04/08 01:36:15 mdw Exp $
- *
- * The RC2 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 "paranoia.h"
-#include "rc2.h"
-#include "rc2-tab.h"
-
-/*----- Global variables --------------------------------------------------*/
-
-const octet rc2_keysz[] = { KSZ_RANGE, RC2_KEYSZ, 1, 128, 1 };
-
-/*----- Important tables --------------------------------------------------*/
-
-static const octet pi[256] = RC2_PI;
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @rc2_braindamage@ --- *
- *
- * Arguments: @rc2_ctx *k@ = pointer to context to initialize
- * @const void *buf@ = pointer to key material
- * @size_t sz@ = size of key material in bytes
- * @unsigned eb@ = desired effective key size, in bits
- *
- * Returns: ---
- *
- * Use: Initializes an RC2 expanded key, and braindamages it to the
- * requested effective key size. This is here for compatibility
- * reasons. You should be using @rc2_init@ in normal code,
- * which doesn't actually apply braindamage.
- */
-
-void rc2_braindamage(rc2_ctx *k, const void *buf, size_t sz, unsigned eb)
-{
- unsigned t8;
- uint16 tm;
- unsigned i;
- uint16 *kk;
- octet l[128];
-
- KSZ_ASSERT(rc2, sz);
-
- /* --- Compute the braindamage parameters --- */
-
- t8 = (eb + 7) / 8;
- tm = 0xff & ((1 << (8 + eb - 8 * t8)) - 1);
-
- /* --- Copy and expand the initial key --- */
-
- if (sz > sizeof(l))
- sz = sizeof(l);
- memcpy(l, buf, sz);
-
- for (i = sz; i < sizeof(l); i++)
- l[i] = pi[U8(l[i - 1] + l[i - sz])];
-
- /* --- Braindamage the key --- */
-
- i = sizeof(l) - t8;
- l[i] = pi[l[i] & tm];
- while (i) {
- i--;
- l[i] = pi[U8(l[i + 1] ^ l[i + t8])];
- }
-
- /* --- Write it to the key block --- */
-
- kk = k->k;
- for (i = 0; i < sizeof(l); i += 2)
- *kk++ = LOAD16_L(l + i);
- BURN(l);
-}
-
-/* --- @rc2_init@ --- *
- *
- * Arguments: @rc2_ctx *k@ = pointer to context to initialize
- * @const void *buf@ = pointer to key material
- * @size_t sz@ = size of key material in bytes
- *
- * Returns: ---
- *
- * Use: Initializes an RC2 expanded key. The effective key size is
- * set to be equal to the real key size, in bits.
- */
-
-void rc2_init(rc2_ctx *k, const void *buf, size_t sz)
-{
- rc2_braindamage(k, buf, sz, sz * 8);
-}
-
-/*----- Encryption and decryption -----------------------------------------*/
-
-#define MIX(a, b, c, d, r, kk) do { \
- a += *kk++ + (d & c) + (~d & b); \
- a = ROL16(a, r); \
-} while (0)
-
-#define MASH(a, d, k) do { \
- a += k[d & 63]; \
-} while (0)
-
-#define UNMIX(a, b, c, d, r, kk) do { \
- a = ROR16(a, r); \
- a -= *--kk + (d & c) + (~d & b); \
-} while (0)
-
-#define UNMASH(a, d, k) do { \
- a -= k[d & 63]; \
-} while (0)
-
-/* --- @rc2_eblk@, @rc2_dblk@ --- *
- *
- * Arguments: @const rc2_ctx *k@ = pointer to RC2 context
- * @const uint32 s[2]@ = pointer to source block
- * @const uint32 d[2]@ = pointer to destination block
- *
- * Returns: ---
- *
- * Use: Low-level block encryption and decryption.
- */
-
-void rc2_eblk(const rc2_ctx *k, const uint32 *s, uint32 *dst)
-{
- uint16 a = U16(s[0] >> 0), b = U16(s[0] >> 16);
- uint16 c = U16(s[1] >> 0), d = U16(s[1] >> 16);
- const uint16 *kk = k->k;
-
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MASH(a, d, k->k); MASH(b, a, k->k);
- MASH(c, b, k->k); MASH(d, c, k->k);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MASH(a, d, k->k); MASH(b, a, k->k);
- MASH(c, b, k->k); MASH(d, c, k->k);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
- MIX(a, b, c, d, 1, kk); MIX(b, c, d, a, 2, kk);
- MIX(c, d, a, b, 3, kk); MIX(d, a, b, c, 5, kk);
-
- dst[0] = a | (b << 16); dst[1] = c | (d << 16);
-}
-
-void rc2_dblk(const rc2_ctx *k, const uint32 *s, uint32 *dst)
-{
- uint16 a = U16(s[0] >> 0), b = U16(s[0] >> 16);
- uint16 c = U16(s[1] >> 0), d = U16(s[1] >> 16);
- const uint16 *kk = k->k + 64;
-
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMASH(d, c, k->k); UNMASH(c, b, k->k);
- UNMASH(b, a, k->k); UNMASH(a, d, k->k);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMASH(d, c, k->k); UNMASH(c, b, k->k);
- UNMASH(b, a, k->k); UNMASH(a, d, k->k);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
- UNMIX(d, a, b, c, 5, kk); UNMIX(c, d, a, b, 3, kk);
- UNMIX(b, c, d, a, 2, kk); UNMIX(a, b, c, d, 1, kk);
-
- dst[0] = a | (b << 16); dst[1] = c | (d << 16);
-}
-
-/*----- Custom test rig ---------------------------------------------------*
- *
- * I need to test the braindamage feature.
- */
-
-#ifdef TEST_RIG
-
-#include <mLib/quis.h>
-#include <mLib/testrig.h>
-
-static int verify(dstr *v)
-{
- rc2_ctx k;
- uint32 p[RC2_BLKSZ / 4];
- uint32 c[RC2_BLKSZ / 4];
- uint32 d[RC2_BLKSZ / 4];
- dstr b = DSTR_INIT;
- unsigned bd = *(unsigned *)v[1].buf;
- int ok = 1;
-
- /* --- Initialize the key buffer --- */
-
- dstr_ensure(&b, RC2_BLKSZ);
- b.len = RC2_BLKSZ;
- rc2_braindamage(&k, v[0].buf, v[0].len, bd);
- BLKC_LOAD(RC2, p, v[2].buf);
- BLKC_LOAD(RC2, c, v[3].buf);
-
- /* --- Test encryption --- */
-
- BLKC_MOVE(RC2, d, p);
- rc2_eblk(&k, d, d);
- BLKC_STORE(RC2, b.buf, d);
- if (memcmp(b.buf, v[3].buf, RC2_BLKSZ)) {
- ok = 0;
- printf("\nfail encryption:"
- "\n\tkey = ");
- type_hex.dump(&v[0], stdout);
- printf("\n\tbraindamage= %u", bd);
- printf("\n\tplaintext = "); type_hex.dump(&v[2], stdout);
- printf("\n\texpected = "); type_hex.dump(&v[3], stdout);
- printf("\n\tcalculated = "); type_hex.dump(&b, stdout);
- putchar('\n');
- }
-
- /* --- Test decryption --- */
-
- BLKC_MOVE(RC2, d, c);
- rc2_dblk(&k, d, d);
- BLKC_STORE(RC2, b.buf, d);
- if (memcmp(b.buf, v[2].buf, RC2_BLKSZ)) {
- ok = 0;
- printf("\nfail decryption:"
- "\n\tkey = ");
- type_hex.dump(&v[0], stdout);
- printf("\n\tbraindamage= %u", bd);
- printf("\n\tciphertext = "); type_hex.dump(&v[3], stdout);
- printf("\n\texpected = "); type_hex.dump(&v[2], stdout);
- printf("\n\tcalculated = "); type_hex.dump(&b, stdout);
- putchar('\n');
- }
-
- /* --- Return --- */
-
- return (ok);
-}
-
-static test_chunk defs[] = {
- { "rc2", verify, { &type_hex, &type_int, &type_hex, &type_hex, 0 } },
- { 0, 0, { 0 } }
-};
-
-int main(int argc, char *argv[])
-{
- test_run(argc, argv, defs, SRCDIR"/tests/rc2");
- return (0);
-}
-
-#endif
-
-/*----- That's all, folks -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff