X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/ba6e6b64033b1f9de49feccb5c9cd438354481f7..0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a:/xtea.c diff --git a/xtea.c b/xtea.c deleted file mode 100644 index 13cb7fd..0000000 --- a/xtea.c +++ /dev/null @@ -1,122 +0,0 @@ -/* -*-c-*- - * - * $Id: xtea.c,v 1.3 2004/04/08 01:36:15 mdw Exp $ - * - * The Extended Tiny Encryption Algorithm - * - * (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 - -#include "blkc.h" -#include "gcipher.h" -#include "paranoia.h" -#include "xtea.h" - -/*----- Global variables --------------------------------------------------*/ - -const octet xtea_keysz[] = { KSZ_RANGE, XTEA_KEYSZ, 0, 16, 1 }; - -/*----- Main code ---------------------------------------------------------*/ - -/* --- @xtea_init@ --- * - * - * Arguments: @xtea_ctx *k@ = pointer to key block - * @const void *buf@ = pointer to key buffer - * @size_t sz@ = size of key material - * - * Returns: --- - * - * Use: Initializes an XTEA key buffer. The key buffer must be 16 - * bytes long. - */ - -void xtea_init(xtea_ctx *k, const void *buf, size_t sz) -{ - octet kb[16]; - const octet *p; - - KSZ_ASSERT(xtea, sz); - if (sz >= sizeof(kb)) - p = buf; - else { - memcpy(kb, buf, sz); - memset(kb + sz, 0, sizeof(kb) - sz); - p = kb; - } - - k->k[0] = LOAD32(p + 0); k->k[1] = LOAD32(p + 4); - k->k[2] = LOAD32(p + 8); k->k[3] = LOAD32(p + 12); - k->r = 32; - - if (p == kb) - BURN(kb); -} - -/* --- @xtea_eblk@, @xtea_dblk@ --- * - * - * Arguments: @const xtea_ctx *k@ = pointer to key block - * @const uint32 s[2]@ = pointer to source block - * @uint32 d[2]@ = pointer to xteatination block - * - * Returns: --- - * - * Use: Low-level block encryption and decryption. - */ - -#define DELTA 0x9e3779b9 - -void xtea_eblk(const xtea_ctx *k, const uint32 *s, uint32 *d) -{ - uint32 y = s[0], z = s[1]; - uint32 n = 0; - unsigned i; - - for (i = 0; i < k->r; i++) { - y = U32(y + ((((z << 4) ^ (z >> 5)) + z) ^ (n + k->k[n & 3]))); - n += DELTA; - z = U32(z + ((((y << 4) ^ (y >> 5)) + y) ^ (n + k->k[(n >> 11) & 3]))); - } - d[0] = y; d[1] = z; -} - -void xtea_dblk(const xtea_ctx *k, const uint32 *s, uint32 *d) -{ - uint32 y = s[0], z = s[1]; - uint32 n = DELTA * k->r; - unsigned i; - - for (i = 0; i < k->r; i++) { - z = U32(z - ((((y << 4) ^ (y >> 5)) + y) ^ (n + k->k[(n >> 11) & 3]))); - n -= DELTA; - y = U32(y - ((((z << 4) ^ (z >> 5)) + z) ^ (n + k->k[n & 3]))); - } - d[0] = y; d[1] = z; -} - -BLKC_TEST(XTEA, xtea) - -/*----- That's all, folks -------------------------------------------------*/