diff options
Diffstat (limited to 'libotr/libgcrypt-1.8.7/cipher/gost28147.c')
-rw-r--r-- | libotr/libgcrypt-1.8.7/cipher/gost28147.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/libotr/libgcrypt-1.8.7/cipher/gost28147.c b/libotr/libgcrypt-1.8.7/cipher/gost28147.c new file mode 100644 index 0000000..4ff80b4 --- /dev/null +++ b/libotr/libgcrypt-1.8.7/cipher/gost28147.c @@ -0,0 +1,227 @@ +/* gost28147.c - GOST 28147-89 implementation for Libgcrypt + * Copyright (C) 2012 Free Software Foundation, Inc. + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt 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 Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* GOST 28147-89 defines several modes of encryption: + * - ECB which should be used only for key transfer + * - CFB mode + * - OFB-like mode with additional transformation on keystream + * RFC 5830 names this 'counter encryption' mode + * Original GOST text uses the term 'gammirovanie' + * - MAC mode + * + * This implementation handles ECB and CFB modes via usual libgcrypt handling. + * OFB-like and MAC modes are unsupported. + */ + +#include <config.h> +#include "types.h" +#include "g10lib.h" +#include "cipher.h" +#include "bufhelp.h" + +#include "gost.h" +#include "gost-sb.h" + +static gcry_err_code_t +gost_setkey (void *c, const byte *key, unsigned keylen) +{ + int i; + GOST28147_context *ctx = c; + + if (keylen != 256 / 8) + return GPG_ERR_INV_KEYLEN; + + if (!ctx->sbox) + ctx->sbox = sbox_test_3411; + + for (i = 0; i < 8; i++) + { + ctx->key[i] = buf_get_le32(&key[4*i]); + } + return GPG_ERR_NO_ERROR; +} + +static u32 +gost_val (GOST28147_context *ctx, u32 cm1, int subkey) +{ + cm1 += ctx->key[subkey]; + cm1 = ctx->sbox[0*256 + ((cm1 >> 0) & 0xff)] | + ctx->sbox[1*256 + ((cm1 >> 8) & 0xff)] | + ctx->sbox[2*256 + ((cm1 >> 16) & 0xff)] | + ctx->sbox[3*256 + ((cm1 >> 24) & 0xff)]; + return cm1; +} + +static unsigned int +_gost_encrypt_data (void *c, u32 *o1, u32 *o2, u32 n1, u32 n2) +{ + GOST28147_context *ctx = c; + + n2 ^= gost_val (ctx, n1, 0); n1 ^= gost_val (ctx, n2, 1); + n2 ^= gost_val (ctx, n1, 2); n1 ^= gost_val (ctx, n2, 3); + n2 ^= gost_val (ctx, n1, 4); n1 ^= gost_val (ctx, n2, 5); + n2 ^= gost_val (ctx, n1, 6); n1 ^= gost_val (ctx, n2, 7); + + n2 ^= gost_val (ctx, n1, 0); n1 ^= gost_val (ctx, n2, 1); + n2 ^= gost_val (ctx, n1, 2); n1 ^= gost_val (ctx, n2, 3); + n2 ^= gost_val (ctx, n1, 4); n1 ^= gost_val (ctx, n2, 5); + n2 ^= gost_val (ctx, n1, 6); n1 ^= gost_val (ctx, n2, 7); + + n2 ^= gost_val (ctx, n1, 0); n1 ^= gost_val (ctx, n2, 1); + n2 ^= gost_val (ctx, n1, 2); n1 ^= gost_val (ctx, n2, 3); + n2 ^= gost_val (ctx, n1, 4); n1 ^= gost_val (ctx, n2, 5); + n2 ^= gost_val (ctx, n1, 6); n1 ^= gost_val (ctx, n2, 7); + + n2 ^= gost_val (ctx, n1, 7); n1 ^= gost_val (ctx, n2, 6); + n2 ^= gost_val (ctx, n1, 5); n1 ^= gost_val (ctx, n2, 4); + n2 ^= gost_val (ctx, n1, 3); n1 ^= gost_val (ctx, n2, 2); + n2 ^= gost_val (ctx, n1, 1); n1 ^= gost_val (ctx, n2, 0); + + *o1 = n2; + *o2 = n1; + + return /* burn_stack */ 4*sizeof(void*) /* func call */ + + 3*sizeof(void*) /* stack */ + + 4*sizeof(void*) /* gost_val call */; +} + +static unsigned int +gost_encrypt_block (void *c, byte *outbuf, const byte *inbuf) +{ + GOST28147_context *ctx = c; + u32 n1, n2; + unsigned int burn; + + n1 = buf_get_le32 (inbuf); + n2 = buf_get_le32 (inbuf+4); + + burn = _gost_encrypt_data(ctx, &n1, &n2, n1, n2); + + buf_put_le32 (outbuf+0, n1); + buf_put_le32 (outbuf+4, n2); + + return /* burn_stack */ burn + 6*sizeof(void*) /* func call */; +} + +unsigned int _gcry_gost_enc_data (GOST28147_context *c, const u32 *key, + u32 *o1, u32 *o2, u32 n1, u32 n2, int cryptopro) +{ + if (cryptopro) + c->sbox = sbox_CryptoPro_3411; + else + c->sbox = sbox_test_3411; + memcpy (c->key, key, 8*4); + return _gost_encrypt_data (c, o1, o2, n1, n2) + 7 * sizeof(void *); +} + +static unsigned int +gost_decrypt_block (void *c, byte *outbuf, const byte *inbuf) +{ + GOST28147_context *ctx = c; + u32 n1, n2; + + n1 = buf_get_le32 (inbuf); + n2 = buf_get_le32 (inbuf+4); + + n2 ^= gost_val (ctx, n1, 0); n1 ^= gost_val (ctx, n2, 1); + n2 ^= gost_val (ctx, n1, 2); n1 ^= gost_val (ctx, n2, 3); + n2 ^= gost_val (ctx, n1, 4); n1 ^= gost_val (ctx, n2, 5); + n2 ^= gost_val (ctx, n1, 6); n1 ^= gost_val (ctx, n2, 7); + + n2 ^= gost_val (ctx, n1, 7); n1 ^= gost_val (ctx, n2, 6); + n2 ^= gost_val (ctx, n1, 5); n1 ^= gost_val (ctx, n2, 4); + n2 ^= gost_val (ctx, n1, 3); n1 ^= gost_val (ctx, n2, 2); + n2 ^= gost_val (ctx, n1, 1); n1 ^= gost_val (ctx, n2, 0); + + n2 ^= gost_val (ctx, n1, 7); n1 ^= gost_val (ctx, n2, 6); + n2 ^= gost_val (ctx, n1, 5); n1 ^= gost_val (ctx, n2, 4); + n2 ^= gost_val (ctx, n1, 3); n1 ^= gost_val (ctx, n2, 2); + n2 ^= gost_val (ctx, n1, 1); n1 ^= gost_val (ctx, n2, 0); + + n2 ^= gost_val (ctx, n1, 7); n1 ^= gost_val (ctx, n2, 6); + n2 ^= gost_val (ctx, n1, 5); n1 ^= gost_val (ctx, n2, 4); + n2 ^= gost_val (ctx, n1, 3); n1 ^= gost_val (ctx, n2, 2); + n2 ^= gost_val (ctx, n1, 1); n1 ^= gost_val (ctx, n2, 0); + + buf_put_le32 (outbuf+0, n2); + buf_put_le32 (outbuf+4, n1); + + return /* burn_stack */ 4*sizeof(void*) /* func call */ + + 3*sizeof(void*) /* stack */ + + 4*sizeof(void*) /* gost_val call */; +} + +static gpg_err_code_t +gost_set_sbox (GOST28147_context *ctx, const char *oid) +{ + int i; + + for (i = 0; gost_oid_map[i].oid; i++) + { + if (!strcmp(gost_oid_map[i].oid, oid)) + { + ctx->sbox = gost_oid_map[i].sbox; + return 0; + } + } + return GPG_ERR_VALUE_NOT_FOUND; +} + +static gpg_err_code_t +gost_set_extra_info (void *c, int what, const void *buffer, size_t buflen) +{ + GOST28147_context *ctx = c; + gpg_err_code_t ec = 0; + + (void)buffer; + (void)buflen; + + switch (what) + { + case GCRYCTL_SET_SBOX: + ec = gost_set_sbox (ctx, buffer); + break; + + default: + ec = GPG_ERR_INV_OP; + break; + } + return ec; +} + +static gcry_cipher_oid_spec_t oids_gost28147[] = + { + /* { "1.2.643.2.2.31.0", GCRY_CIPHER_MODE_CNTGOST }, */ + { "1.2.643.2.2.31.1", GCRY_CIPHER_MODE_CFB }, + { "1.2.643.2.2.31.2", GCRY_CIPHER_MODE_CFB }, + { "1.2.643.2.2.31.3", GCRY_CIPHER_MODE_CFB }, + { "1.2.643.2.2.31.4", GCRY_CIPHER_MODE_CFB }, + { NULL } + }; + +gcry_cipher_spec_t _gcry_cipher_spec_gost28147 = + { + GCRY_CIPHER_GOST28147, {0, 0}, + "GOST28147", NULL, oids_gost28147, 8, 256, + sizeof (GOST28147_context), + gost_setkey, + gost_encrypt_block, + gost_decrypt_block, + NULL, NULL, NULL, gost_set_extra_info, + }; |