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-rw-r--r--crypto/xcbc.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/crypto/xcbc.c b/crypto/xcbc.c
new file mode 100644
index 000000000000..9347eb6bcf69
--- /dev/null
+++ b/crypto/xcbc.c
@@ -0,0 +1,348 @@
1/*
2 * Copyright (C)2006 USAGI/WIDE Project
3 *
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.
8 *
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.
13 *
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
17 *
18 * Author:
19 * Kazunori Miyazawa <miyazawa@linux-ipv6.org>
20 */
21
22#include <linux/crypto.h>
23#include <linux/err.h>
24#include <linux/kernel.h>
25#include <linux/mm.h>
26#include <linux/rtnetlink.h>
27#include <linux/slab.h>
28#include <linux/scatterlist.h>
29#include "internal.h"
30
31static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101,
32 0x02020202, 0x02020202, 0x02020202, 0x02020202,
33 0x03030303, 0x03030303, 0x03030303, 0x03030303};
34/*
35 * +------------------------
36 * | <parent tfm>
37 * +------------------------
38 * | crypto_xcbc_ctx
39 * +------------------------
40 * | odds (block size)
41 * +------------------------
42 * | prev (block size)
43 * +------------------------
44 * | key (block size)
45 * +------------------------
46 * | consts (block size * 3)
47 * +------------------------
48 */
49struct crypto_xcbc_ctx {
50 struct crypto_tfm *child;
51 u8 *odds;
52 u8 *prev;
53 u8 *key;
54 u8 *consts;
55 void (*xor)(u8 *a, const u8 *b, unsigned int bs);
56 unsigned int keylen;
57 unsigned int len;
58};
59
60static void xor_128(u8 *a, const u8 *b, unsigned int bs)
61{
62 ((u32 *)a)[0] ^= ((u32 *)b)[0];
63 ((u32 *)a)[1] ^= ((u32 *)b)[1];
64 ((u32 *)a)[2] ^= ((u32 *)b)[2];
65 ((u32 *)a)[3] ^= ((u32 *)b)[3];
66}
67
68static int _crypto_xcbc_digest_setkey(struct crypto_hash *parent,
69 struct crypto_xcbc_ctx *ctx)
70{
71 int bs = crypto_hash_blocksize(parent);
72 int err = 0;
73 u8 key1[bs];
74
75 if ((err = crypto_cipher_setkey(ctx->child, ctx->key, ctx->keylen)))
76 return err;
77
78 ctx->child->__crt_alg->cra_cipher.cia_encrypt(ctx->child, key1,
79 ctx->consts);
80
81 return crypto_cipher_setkey(ctx->child, key1, bs);
82}
83
84static int crypto_xcbc_digest_setkey(struct crypto_hash *parent,
85 const u8 *inkey, unsigned int keylen)
86{
87 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
88
89 if (keylen != crypto_tfm_alg_blocksize(ctx->child))
90 return -EINVAL;
91
92 ctx->keylen = keylen;
93 memcpy(ctx->key, inkey, keylen);
94 ctx->consts = (u8*)ks;
95
96 return _crypto_xcbc_digest_setkey(parent, ctx);
97}
98
99static int crypto_xcbc_digest_init(struct hash_desc *pdesc)
100{
101 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(pdesc->tfm);
102 int bs = crypto_hash_blocksize(pdesc->tfm);
103
104 ctx->len = 0;
105 memset(ctx->odds, 0, bs);
106 memset(ctx->prev, 0, bs);
107
108 return 0;
109}
110
111static int crypto_xcbc_digest_update(struct hash_desc *pdesc,
112 struct scatterlist *sg,
113 unsigned int nbytes)
114{
115 struct crypto_hash *parent = pdesc->tfm;
116 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
117 struct crypto_tfm *tfm = ctx->child;
118 int bs = crypto_hash_blocksize(parent);
119 unsigned int i = 0;
120
121 do {
122
123 struct page *pg = sg[i].page;
124 unsigned int offset = sg[i].offset;
125 unsigned int slen = sg[i].length;
126
127 while (slen > 0) {
128 unsigned int len = min(slen, ((unsigned int)(PAGE_SIZE)) - offset);
129 char *p = crypto_kmap(pg, 0) + offset;
130
131 /* checking the data can fill the block */
132 if ((ctx->len + len) <= bs) {
133 memcpy(ctx->odds + ctx->len, p, len);
134 ctx->len += len;
135 slen -= len;
136
137 /* checking the rest of the page */
138 if (len + offset >= PAGE_SIZE) {
139 offset = 0;
140 pg++;
141 } else
142 offset += len;
143
144 crypto_kunmap(p, 0);
145 crypto_yield(tfm->crt_flags);
146 continue;
147 }
148
149 /* filling odds with new data and encrypting it */
150 memcpy(ctx->odds + ctx->len, p, bs - ctx->len);
151 len -= bs - ctx->len;
152 p += bs - ctx->len;
153
154 ctx->xor(ctx->prev, ctx->odds, bs);
155 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, ctx->prev, ctx->prev);
156
157 /* clearing the length */
158 ctx->len = 0;
159
160 /* encrypting the rest of data */
161 while (len > bs) {
162 ctx->xor(ctx->prev, p, bs);
163 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, ctx->prev, ctx->prev);
164 p += bs;
165 len -= bs;
166 }
167
168 /* keeping the surplus of blocksize */
169 if (len) {
170 memcpy(ctx->odds, p, len);
171 ctx->len = len;
172 }
173 crypto_kunmap(p, 0);
174 crypto_yield(tfm->crt_flags);
175 slen -= min(slen, ((unsigned int)(PAGE_SIZE)) - offset);
176 offset = 0;
177 pg++;
178 }
179 nbytes-=sg[i].length;
180 i++;
181 } while (nbytes>0);
182
183 return 0;
184}
185
186static int crypto_xcbc_digest_final(struct hash_desc *pdesc, u8 *out)
187{
188 struct crypto_hash *parent = pdesc->tfm;
189 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
190 struct crypto_tfm *tfm = ctx->child;
191 int bs = crypto_hash_blocksize(parent);
192 int err = 0;
193
194 if (ctx->len == bs) {
195 u8 key2[bs];
196
197 if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)
198 return err;
199
200 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key2, (const u8*)(ctx->consts+bs));
201
202 ctx->xor(ctx->prev, ctx->odds, bs);
203 ctx->xor(ctx->prev, key2, bs);
204 _crypto_xcbc_digest_setkey(parent, ctx);
205
206 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, out, ctx->prev);
207 } else {
208 u8 key3[bs];
209 unsigned int rlen;
210 u8 *p = ctx->odds + ctx->len;
211 *p = 0x80;
212 p++;
213
214 rlen = bs - ctx->len -1;
215 if (rlen)
216 memset(p, 0, rlen);
217
218 if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)
219 return err;
220
221 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key3, (const u8*)(ctx->consts+bs*2));
222
223 ctx->xor(ctx->prev, ctx->odds, bs);
224 ctx->xor(ctx->prev, key3, bs);
225
226 _crypto_xcbc_digest_setkey(parent, ctx);
227
228 tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, out, ctx->prev);
229 }
230
231 return 0;
232}
233
234static int crypto_xcbc_digest(struct hash_desc *pdesc,
235 struct scatterlist *sg, unsigned int nbytes, u8 *out)
236{
237 crypto_xcbc_digest_init(pdesc);
238 crypto_xcbc_digest_update(pdesc, sg, nbytes);
239 return crypto_xcbc_digest_final(pdesc, out);
240}
241
242static int xcbc_init_tfm(struct crypto_tfm *tfm)
243{
244 struct crypto_instance *inst = (void *)tfm->__crt_alg;
245 struct crypto_spawn *spawn = crypto_instance_ctx(inst);
246 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));
247 int bs = crypto_hash_blocksize(__crypto_hash_cast(tfm));
248
249 tfm = crypto_spawn_tfm(spawn);
250 if (IS_ERR(tfm))
251 return PTR_ERR(tfm);
252
253 switch(bs) {
254 case 16:
255 ctx->xor = xor_128;
256 break;
257 default:
258 return -EINVAL;
259 }
260
261 ctx->child = crypto_cipher_cast(tfm);
262 ctx->odds = (u8*)(ctx+1);
263 ctx->prev = ctx->odds + bs;
264 ctx->key = ctx->prev + bs;
265
266 return 0;
267};
268
269static void xcbc_exit_tfm(struct crypto_tfm *tfm)
270{
271 struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));
272 crypto_free_cipher(ctx->child);
273}
274
275static struct crypto_instance *xcbc_alloc(void *param, unsigned int len)
276{
277 struct crypto_instance *inst;
278 struct crypto_alg *alg;
279 alg = crypto_get_attr_alg(param, len, CRYPTO_ALG_TYPE_CIPHER,
280 CRYPTO_ALG_TYPE_HASH_MASK | CRYPTO_ALG_ASYNC);
281 if (IS_ERR(alg))
282 return ERR_PTR(PTR_ERR(alg));
283
284 switch(alg->cra_blocksize) {
285 case 16:
286 break;
287 default:
288 return ERR_PTR(PTR_ERR(alg));
289 }
290
291 inst = crypto_alloc_instance("xcbc", alg);
292 if (IS_ERR(inst))
293 goto out_put_alg;
294
295 inst->alg.cra_flags = CRYPTO_ALG_TYPE_HASH;
296 inst->alg.cra_priority = alg->cra_priority;
297 inst->alg.cra_blocksize = alg->cra_blocksize;
298 inst->alg.cra_alignmask = alg->cra_alignmask;
299 inst->alg.cra_type = &crypto_hash_type;
300
301 inst->alg.cra_hash.digestsize =
302 (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
303 CRYPTO_ALG_TYPE_HASH ? alg->cra_hash.digestsize :
304 alg->cra_blocksize;
305 inst->alg.cra_ctxsize = sizeof(struct crypto_xcbc_ctx) +
306 ALIGN(inst->alg.cra_blocksize * 3, sizeof(void *));
307 inst->alg.cra_init = xcbc_init_tfm;
308 inst->alg.cra_exit = xcbc_exit_tfm;
309
310 inst->alg.cra_hash.init = crypto_xcbc_digest_init;
311 inst->alg.cra_hash.update = crypto_xcbc_digest_update;
312 inst->alg.cra_hash.final = crypto_xcbc_digest_final;
313 inst->alg.cra_hash.digest = crypto_xcbc_digest;
314 inst->alg.cra_hash.setkey = crypto_xcbc_digest_setkey;
315
316out_put_alg:
317 crypto_mod_put(alg);
318 return inst;
319}
320
321static void xcbc_free(struct crypto_instance *inst)
322{
323 crypto_drop_spawn(crypto_instance_ctx(inst));
324 kfree(inst);
325}
326
327static struct crypto_template crypto_xcbc_tmpl = {
328 .name = "xcbc",
329 .alloc = xcbc_alloc,
330 .free = xcbc_free,
331 .module = THIS_MODULE,
332};
333
334static int __init crypto_xcbc_module_init(void)
335{
336 return crypto_register_template(&crypto_xcbc_tmpl);
337}
338
339static void __exit crypto_xcbc_module_exit(void)
340{
341 crypto_unregister_template(&crypto_xcbc_tmpl);
342}
343
344module_init(crypto_xcbc_module_init);
345module_exit(crypto_xcbc_module_exit);
346
347MODULE_LICENSE("GPL");
348MODULE_DESCRIPTION("XCBC keyed hash algorithm");
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