2 * Copyright (C)2006 USAGI/WIDE Project
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 * Kazunori Miyazawa <miyazawa@linux-ipv6.org>
22 #include <crypto/internal/hash.h>
23 #include <linux/err.h>
24 #include <linux/kernel.h>
26 static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101,
27 0x02020202, 0x02020202, 0x02020202, 0x02020202,
28 0x03030303, 0x03030303, 0x03030303, 0x03030303};
31 * +------------------------
33 * +------------------------
35 * +------------------------
36 * | consts (block size * 2)
37 * +------------------------
40 struct crypto_cipher *child;
45 * +------------------------
47 * +------------------------
49 * +------------------------
51 * +------------------------
53 * +------------------------
55 struct xcbc_desc_ctx {
60 static int crypto_xcbc_digest_setkey(struct crypto_shash *parent,
61 const u8 *inkey, unsigned int keylen)
63 unsigned long alignmask = crypto_shash_alignmask(parent);
64 struct xcbc_tfm_ctx *ctx = crypto_shash_ctx(parent);
65 int bs = crypto_shash_blocksize(parent);
66 u8 *consts = PTR_ALIGN(&ctx->ctx[0], alignmask + 1);
70 if ((err = crypto_cipher_setkey(ctx->child, inkey, keylen)))
73 crypto_cipher_encrypt_one(ctx->child, consts, (u8 *)ks + bs);
74 crypto_cipher_encrypt_one(ctx->child, consts + bs, (u8 *)ks + bs * 2);
75 crypto_cipher_encrypt_one(ctx->child, key1, (u8 *)ks);
77 return crypto_cipher_setkey(ctx->child, key1, bs);
81 static int crypto_xcbc_digest_init(struct shash_desc *pdesc)
83 unsigned long alignmask = crypto_shash_alignmask(pdesc->tfm);
84 struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc);
85 int bs = crypto_shash_blocksize(pdesc->tfm);
86 u8 *prev = PTR_ALIGN(&ctx->ctx[0], alignmask + 1) + bs;
94 static int crypto_xcbc_digest_update(struct shash_desc *pdesc, const u8 *p,
97 struct crypto_shash *parent = pdesc->tfm;
98 unsigned long alignmask = crypto_shash_alignmask(parent);
99 struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent);
100 struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc);
101 struct crypto_cipher *tfm = tctx->child;
102 int bs = crypto_shash_blocksize(parent);
103 u8 *odds = PTR_ALIGN(&ctx->ctx[0], alignmask + 1);
104 u8 *prev = odds + bs;
106 /* checking the data can fill the block */
107 if ((ctx->len + len) <= bs) {
108 memcpy(odds + ctx->len, p, len);
113 /* filling odds with new data and encrypting it */
114 memcpy(odds + ctx->len, p, bs - ctx->len);
115 len -= bs - ctx->len;
118 crypto_xor(prev, odds, bs);
119 crypto_cipher_encrypt_one(tfm, prev, prev);
121 /* clearing the length */
124 /* encrypting the rest of data */
126 crypto_xor(prev, p, bs);
127 crypto_cipher_encrypt_one(tfm, prev, prev);
132 /* keeping the surplus of blocksize */
134 memcpy(odds, p, len);
141 static int crypto_xcbc_digest_final(struct shash_desc *pdesc, u8 *out)
143 struct crypto_shash *parent = pdesc->tfm;
144 unsigned long alignmask = crypto_shash_alignmask(parent);
145 struct xcbc_tfm_ctx *tctx = crypto_shash_ctx(parent);
146 struct xcbc_desc_ctx *ctx = shash_desc_ctx(pdesc);
147 struct crypto_cipher *tfm = tctx->child;
148 int bs = crypto_shash_blocksize(parent);
149 u8 *consts = PTR_ALIGN(&tctx->ctx[0], alignmask + 1);
150 u8 *odds = PTR_ALIGN(&ctx->ctx[0], alignmask + 1);
151 u8 *prev = odds + bs;
152 unsigned int offset = 0;
154 if (ctx->len != bs) {
156 u8 *p = odds + ctx->len;
161 rlen = bs - ctx->len -1;
168 crypto_xor(prev, odds, bs);
169 crypto_xor(prev, consts + offset, bs);
171 crypto_cipher_encrypt_one(tfm, out, prev);
176 static int xcbc_init_tfm(struct crypto_tfm *tfm)
178 struct crypto_cipher *cipher;
179 struct crypto_instance *inst = (void *)tfm->__crt_alg;
180 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
181 struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
183 cipher = crypto_spawn_cipher(spawn);
185 return PTR_ERR(cipher);
192 static void xcbc_exit_tfm(struct crypto_tfm *tfm)
194 struct xcbc_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
195 crypto_free_cipher(ctx->child);
198 static int xcbc_create(struct crypto_template *tmpl, struct rtattr **tb)
200 struct shash_instance *inst;
201 struct crypto_alg *alg;
202 unsigned long alignmask;
205 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
209 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
210 CRYPTO_ALG_TYPE_MASK);
214 switch(alg->cra_blocksize) {
221 inst = shash_alloc_instance("xcbc", alg);
226 err = crypto_init_spawn(shash_instance_ctx(inst), alg,
227 shash_crypto_instance(inst),
228 CRYPTO_ALG_TYPE_MASK);
232 alignmask = alg->cra_alignmask | 3;
233 inst->alg.base.cra_alignmask = alignmask;
234 inst->alg.base.cra_priority = alg->cra_priority;
235 inst->alg.base.cra_blocksize = alg->cra_blocksize;
237 inst->alg.digestsize = alg->cra_blocksize;
238 inst->alg.descsize = ALIGN(sizeof(struct xcbc_desc_ctx),
239 crypto_tfm_ctx_alignment()) +
241 ~(crypto_tfm_ctx_alignment() - 1)) +
242 alg->cra_blocksize * 2;
244 inst->alg.base.cra_ctxsize = ALIGN(sizeof(struct xcbc_tfm_ctx),
246 alg->cra_blocksize * 2;
247 inst->alg.base.cra_init = xcbc_init_tfm;
248 inst->alg.base.cra_exit = xcbc_exit_tfm;
250 inst->alg.init = crypto_xcbc_digest_init;
251 inst->alg.update = crypto_xcbc_digest_update;
252 inst->alg.final = crypto_xcbc_digest_final;
253 inst->alg.setkey = crypto_xcbc_digest_setkey;
255 err = shash_register_instance(tmpl, inst);
258 shash_free_instance(shash_crypto_instance(inst));
266 static struct crypto_template crypto_xcbc_tmpl = {
268 .create = xcbc_create,
269 .free = shash_free_instance,
270 .module = THIS_MODULE,
273 static int __init crypto_xcbc_module_init(void)
275 return crypto_register_template(&crypto_xcbc_tmpl);
278 static void __exit crypto_xcbc_module_exit(void)
280 crypto_unregister_template(&crypto_xcbc_tmpl);
283 module_init(crypto_xcbc_module_init);
284 module_exit(crypto_xcbc_module_exit);
286 MODULE_LICENSE("GPL");
287 MODULE_DESCRIPTION("XCBC keyed hash algorithm");