Commit | Line | Data |
---|---|---|
64470f1b RS |
1 | /* LRW: as defined by Cyril Guyot in |
2 | * http://grouper.ieee.org/groups/1619/email/pdf00017.pdf | |
3 | * | |
4 | * Copyright (c) 2006 Rik Snel <rsnel@cube.dyndns.org> | |
5 | * | |
6c2205b8 | 6 | * Based on ecb.c |
64470f1b RS |
7 | * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify it | |
10 | * under the terms of the GNU General Public License as published by the Free | |
11 | * Software Foundation; either version 2 of the License, or (at your option) | |
12 | * any later version. | |
13 | */ | |
14 | /* This implementation is checked against the test vectors in the above | |
15 | * document and by a test vector provided by Ken Buchanan at | |
16 | * http://www.mail-archive.com/stds-p1619@listserv.ieee.org/msg00173.html | |
17 | * | |
18 | * The test vectors are included in the testing module tcrypt.[ch] */ | |
6c2205b8 | 19 | |
700cb3f5 HX |
20 | #include <crypto/internal/skcipher.h> |
21 | #include <crypto/scatterwalk.h> | |
64470f1b RS |
22 | #include <linux/err.h> |
23 | #include <linux/init.h> | |
24 | #include <linux/kernel.h> | |
25 | #include <linux/module.h> | |
26 | #include <linux/scatterlist.h> | |
27 | #include <linux/slab.h> | |
28 | ||
29 | #include <crypto/b128ops.h> | |
30 | #include <crypto/gf128mul.h> | |
64470f1b | 31 | |
700cb3f5 HX |
32 | #define LRW_BUFFER_SIZE 128u |
33 | ||
217afccf EB |
34 | #define LRW_BLOCK_SIZE 16 |
35 | ||
171c0204 | 36 | struct priv { |
700cb3f5 | 37 | struct crypto_skcipher *child; |
217afccf EB |
38 | |
39 | /* | |
40 | * optimizes multiplying a random (non incrementing, as at the | |
41 | * start of a new sector) value with key2, we could also have | |
42 | * used 4k optimization tables or no optimization at all. In the | |
43 | * latter case we would have to store key2 here | |
44 | */ | |
45 | struct gf128mul_64k *table; | |
46 | ||
47 | /* | |
48 | * stores: | |
49 | * key2*{ 0,0,...0,0,0,0,1 }, key2*{ 0,0,...0,0,0,1,1 }, | |
50 | * key2*{ 0,0,...0,0,1,1,1 }, key2*{ 0,0,...0,1,1,1,1 } | |
51 | * key2*{ 0,0,...1,1,1,1,1 }, etc | |
52 | * needed for optimized multiplication of incrementing values | |
53 | * with key2 | |
54 | */ | |
55 | be128 mulinc[128]; | |
171c0204 JK |
56 | }; |
57 | ||
700cb3f5 HX |
58 | struct rctx { |
59 | be128 buf[LRW_BUFFER_SIZE / sizeof(be128)]; | |
60 | ||
61 | be128 t; | |
62 | ||
63 | be128 *ext; | |
64 | ||
65 | struct scatterlist srcbuf[2]; | |
66 | struct scatterlist dstbuf[2]; | |
67 | struct scatterlist *src; | |
68 | struct scatterlist *dst; | |
69 | ||
70 | unsigned int left; | |
71 | ||
72 | struct skcipher_request subreq; | |
73 | }; | |
74 | ||
64470f1b RS |
75 | static inline void setbit128_bbe(void *b, int bit) |
76 | { | |
8eb2dfac HX |
77 | __set_bit(bit ^ (0x80 - |
78 | #ifdef __BIG_ENDIAN | |
79 | BITS_PER_LONG | |
80 | #else | |
81 | BITS_PER_BYTE | |
82 | #endif | |
83 | ), b); | |
64470f1b RS |
84 | } |
85 | ||
217afccf EB |
86 | static int setkey(struct crypto_skcipher *parent, const u8 *key, |
87 | unsigned int keylen) | |
64470f1b | 88 | { |
217afccf EB |
89 | struct priv *ctx = crypto_skcipher_ctx(parent); |
90 | struct crypto_skcipher *child = ctx->child; | |
91 | int err, bsize = LRW_BLOCK_SIZE; | |
92 | const u8 *tweak = key + keylen - bsize; | |
64470f1b | 93 | be128 tmp = { 0 }; |
171c0204 | 94 | int i; |
64470f1b | 95 | |
217afccf EB |
96 | crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); |
97 | crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) & | |
98 | CRYPTO_TFM_REQ_MASK); | |
99 | err = crypto_skcipher_setkey(child, key, keylen - bsize); | |
100 | crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & | |
101 | CRYPTO_TFM_RES_MASK); | |
102 | if (err) | |
103 | return err; | |
104 | ||
64470f1b RS |
105 | if (ctx->table) |
106 | gf128mul_free_64k(ctx->table); | |
107 | ||
108 | /* initialize multiplication table for Key2 */ | |
171c0204 | 109 | ctx->table = gf128mul_init_64k_bbe((be128 *)tweak); |
64470f1b RS |
110 | if (!ctx->table) |
111 | return -ENOMEM; | |
112 | ||
113 | /* initialize optimization table */ | |
114 | for (i = 0; i < 128; i++) { | |
115 | setbit128_bbe(&tmp, i); | |
116 | ctx->mulinc[i] = tmp; | |
117 | gf128mul_64k_bbe(&ctx->mulinc[i], ctx->table); | |
118 | } | |
119 | ||
120 | return 0; | |
121 | } | |
171c0204 | 122 | |
c778f96b OM |
123 | /* |
124 | * Returns the number of trailing '1' bits in the words of the counter, which is | |
125 | * represented by 4 32-bit words, arranged from least to most significant. | |
126 | * At the same time, increments the counter by one. | |
127 | * | |
128 | * For example: | |
129 | * | |
130 | * u32 counter[4] = { 0xFFFFFFFF, 0x1, 0x0, 0x0 }; | |
131 | * int i = next_index(&counter); | |
132 | * // i == 33, counter == { 0x0, 0x2, 0x0, 0x0 } | |
133 | */ | |
134 | static int next_index(u32 *counter) | |
64470f1b | 135 | { |
c778f96b | 136 | int i, res = 0; |
64470f1b | 137 | |
c778f96b OM |
138 | for (i = 0; i < 4; i++) { |
139 | if (counter[i] + 1 != 0) { | |
140 | res += ffz(counter[i]++); | |
141 | break; | |
142 | } | |
143 | counter[i] = 0; | |
144 | res += 32; | |
64470f1b RS |
145 | } |
146 | ||
fbe1a850 OM |
147 | /* |
148 | * If we get here, then x == 128 and we are incrementing the counter | |
149 | * from all ones to all zeros. This means we must return index 127, i.e. | |
150 | * the one corresponding to key2*{ 1,...,1 }. | |
151 | */ | |
152 | return 127; | |
64470f1b RS |
153 | } |
154 | ||
700cb3f5 | 155 | static int post_crypt(struct skcipher_request *req) |
64470f1b | 156 | { |
700cb3f5 HX |
157 | struct rctx *rctx = skcipher_request_ctx(req); |
158 | be128 *buf = rctx->ext ?: rctx->buf; | |
159 | struct skcipher_request *subreq; | |
160 | const int bs = LRW_BLOCK_SIZE; | |
161 | struct skcipher_walk w; | |
162 | struct scatterlist *sg; | |
163 | unsigned offset; | |
64470f1b | 164 | int err; |
700cb3f5 HX |
165 | |
166 | subreq = &rctx->subreq; | |
167 | err = skcipher_walk_virt(&w, subreq, false); | |
168 | ||
169 | while (w.nbytes) { | |
170 | unsigned int avail = w.nbytes; | |
171 | be128 *wdst; | |
172 | ||
173 | wdst = w.dst.virt.addr; | |
174 | ||
175 | do { | |
176 | be128_xor(wdst, buf++, wdst); | |
177 | wdst++; | |
178 | } while ((avail -= bs) >= bs); | |
179 | ||
180 | err = skcipher_walk_done(&w, avail); | |
181 | } | |
182 | ||
183 | rctx->left -= subreq->cryptlen; | |
184 | ||
185 | if (err || !rctx->left) | |
186 | goto out; | |
187 | ||
188 | rctx->dst = rctx->dstbuf; | |
189 | ||
190 | scatterwalk_done(&w.out, 0, 1); | |
191 | sg = w.out.sg; | |
192 | offset = w.out.offset; | |
193 | ||
194 | if (rctx->dst != sg) { | |
195 | rctx->dst[0] = *sg; | |
196 | sg_unmark_end(rctx->dst); | |
8c30fbe6 | 197 | scatterwalk_crypto_chain(rctx->dst, sg_next(sg), 2); |
700cb3f5 HX |
198 | } |
199 | rctx->dst[0].length -= offset - sg->offset; | |
200 | rctx->dst[0].offset = offset; | |
201 | ||
202 | out: | |
203 | return err; | |
204 | } | |
205 | ||
206 | static int pre_crypt(struct skcipher_request *req) | |
207 | { | |
208 | struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); | |
209 | struct rctx *rctx = skcipher_request_ctx(req); | |
210 | struct priv *ctx = crypto_skcipher_ctx(tfm); | |
211 | be128 *buf = rctx->ext ?: rctx->buf; | |
212 | struct skcipher_request *subreq; | |
4660720d | 213 | const int bs = LRW_BLOCK_SIZE; |
700cb3f5 HX |
214 | struct skcipher_walk w; |
215 | struct scatterlist *sg; | |
216 | unsigned cryptlen; | |
217 | unsigned offset; | |
700cb3f5 | 218 | bool more; |
c778f96b OM |
219 | __be32 *iv; |
220 | u32 counter[4]; | |
700cb3f5 | 221 | int err; |
64470f1b | 222 | |
700cb3f5 HX |
223 | subreq = &rctx->subreq; |
224 | skcipher_request_set_tfm(subreq, tfm); | |
64470f1b | 225 | |
700cb3f5 HX |
226 | cryptlen = subreq->cryptlen; |
227 | more = rctx->left > cryptlen; | |
228 | if (!more) | |
229 | cryptlen = rctx->left; | |
64470f1b | 230 | |
700cb3f5 HX |
231 | skcipher_request_set_crypt(subreq, rctx->src, rctx->dst, |
232 | cryptlen, req->iv); | |
64470f1b | 233 | |
700cb3f5 | 234 | err = skcipher_walk_virt(&w, subreq, false); |
c778f96b OM |
235 | iv = (__be32 *)w.iv; |
236 | ||
237 | counter[0] = be32_to_cpu(iv[3]); | |
238 | counter[1] = be32_to_cpu(iv[2]); | |
239 | counter[2] = be32_to_cpu(iv[1]); | |
240 | counter[3] = be32_to_cpu(iv[0]); | |
64470f1b | 241 | |
700cb3f5 HX |
242 | while (w.nbytes) { |
243 | unsigned int avail = w.nbytes; | |
244 | be128 *wsrc; | |
245 | be128 *wdst; | |
246 | ||
247 | wsrc = w.src.virt.addr; | |
248 | wdst = w.dst.virt.addr; | |
64470f1b | 249 | |
64470f1b | 250 | do { |
700cb3f5 HX |
251 | *buf++ = rctx->t; |
252 | be128_xor(wdst++, &rctx->t, wsrc++); | |
253 | ||
64470f1b RS |
254 | /* T <- I*Key2, using the optimization |
255 | * discussed in the specification */ | |
700cb3f5 | 256 | be128_xor(&rctx->t, &rctx->t, |
c778f96b | 257 | &ctx->mulinc[next_index(counter)]); |
700cb3f5 | 258 | } while ((avail -= bs) >= bs); |
64470f1b | 259 | |
c778f96b OM |
260 | if (w.nbytes == w.total) { |
261 | iv[0] = cpu_to_be32(counter[3]); | |
262 | iv[1] = cpu_to_be32(counter[2]); | |
263 | iv[2] = cpu_to_be32(counter[1]); | |
264 | iv[3] = cpu_to_be32(counter[0]); | |
265 | } | |
266 | ||
700cb3f5 HX |
267 | err = skcipher_walk_done(&w, avail); |
268 | } | |
64470f1b | 269 | |
700cb3f5 HX |
270 | skcipher_request_set_tfm(subreq, ctx->child); |
271 | skcipher_request_set_crypt(subreq, rctx->dst, rctx->dst, | |
272 | cryptlen, NULL); | |
64470f1b | 273 | |
700cb3f5 HX |
274 | if (err || !more) |
275 | goto out; | |
276 | ||
277 | rctx->src = rctx->srcbuf; | |
278 | ||
279 | scatterwalk_done(&w.in, 0, 1); | |
280 | sg = w.in.sg; | |
281 | offset = w.in.offset; | |
282 | ||
283 | if (rctx->src != sg) { | |
284 | rctx->src[0] = *sg; | |
285 | sg_unmark_end(rctx->src); | |
8c30fbe6 | 286 | scatterwalk_crypto_chain(rctx->src, sg_next(sg), 2); |
700cb3f5 HX |
287 | } |
288 | rctx->src[0].length -= offset - sg->offset; | |
289 | rctx->src[0].offset = offset; | |
290 | ||
291 | out: | |
292 | return err; | |
293 | } | |
294 | ||
295 | static int init_crypt(struct skcipher_request *req, crypto_completion_t done) | |
296 | { | |
297 | struct priv *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); | |
298 | struct rctx *rctx = skcipher_request_ctx(req); | |
299 | struct skcipher_request *subreq; | |
300 | gfp_t gfp; | |
301 | ||
302 | subreq = &rctx->subreq; | |
303 | skcipher_request_set_callback(subreq, req->base.flags, done, req); | |
304 | ||
305 | gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL : | |
306 | GFP_ATOMIC; | |
307 | rctx->ext = NULL; | |
308 | ||
309 | subreq->cryptlen = LRW_BUFFER_SIZE; | |
310 | if (req->cryptlen > LRW_BUFFER_SIZE) { | |
9df0eb18 EB |
311 | unsigned int n = min(req->cryptlen, (unsigned int)PAGE_SIZE); |
312 | ||
313 | rctx->ext = kmalloc(n, gfp); | |
314 | if (rctx->ext) | |
315 | subreq->cryptlen = n; | |
700cb3f5 HX |
316 | } |
317 | ||
318 | rctx->src = req->src; | |
319 | rctx->dst = req->dst; | |
320 | rctx->left = req->cryptlen; | |
321 | ||
322 | /* calculate first value of T */ | |
323 | memcpy(&rctx->t, req->iv, sizeof(rctx->t)); | |
324 | ||
325 | /* T <- I*Key2 */ | |
217afccf | 326 | gf128mul_64k_bbe(&rctx->t, ctx->table); |
64470f1b | 327 | |
700cb3f5 HX |
328 | return 0; |
329 | } | |
330 | ||
331 | static void exit_crypt(struct skcipher_request *req) | |
332 | { | |
333 | struct rctx *rctx = skcipher_request_ctx(req); | |
334 | ||
335 | rctx->left = 0; | |
336 | ||
337 | if (rctx->ext) | |
8c9bdab2 | 338 | kzfree(rctx->ext); |
700cb3f5 HX |
339 | } |
340 | ||
341 | static int do_encrypt(struct skcipher_request *req, int err) | |
342 | { | |
343 | struct rctx *rctx = skcipher_request_ctx(req); | |
344 | struct skcipher_request *subreq; | |
345 | ||
346 | subreq = &rctx->subreq; | |
347 | ||
348 | while (!err && rctx->left) { | |
349 | err = pre_crypt(req) ?: | |
350 | crypto_skcipher_encrypt(subreq) ?: | |
351 | post_crypt(req); | |
352 | ||
4e5b0ad5 | 353 | if (err == -EINPROGRESS || err == -EBUSY) |
700cb3f5 | 354 | return err; |
64470f1b RS |
355 | } |
356 | ||
700cb3f5 | 357 | exit_crypt(req); |
64470f1b RS |
358 | return err; |
359 | } | |
360 | ||
700cb3f5 HX |
361 | static void encrypt_done(struct crypto_async_request *areq, int err) |
362 | { | |
363 | struct skcipher_request *req = areq->data; | |
364 | struct skcipher_request *subreq; | |
365 | struct rctx *rctx; | |
366 | ||
367 | rctx = skcipher_request_ctx(req); | |
4702bbee HX |
368 | |
369 | if (err == -EINPROGRESS) { | |
370 | if (rctx->left != req->cryptlen) | |
371 | return; | |
372 | goto out; | |
373 | } | |
374 | ||
700cb3f5 HX |
375 | subreq = &rctx->subreq; |
376 | subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG; | |
377 | ||
378 | err = do_encrypt(req, err ?: post_crypt(req)); | |
379 | if (rctx->left) | |
380 | return; | |
381 | ||
4702bbee | 382 | out: |
700cb3f5 HX |
383 | skcipher_request_complete(req, err); |
384 | } | |
385 | ||
386 | static int encrypt(struct skcipher_request *req) | |
387 | { | |
388 | return do_encrypt(req, init_crypt(req, encrypt_done)); | |
389 | } | |
390 | ||
391 | static int do_decrypt(struct skcipher_request *req, int err) | |
64470f1b | 392 | { |
700cb3f5 HX |
393 | struct rctx *rctx = skcipher_request_ctx(req); |
394 | struct skcipher_request *subreq; | |
395 | ||
396 | subreq = &rctx->subreq; | |
397 | ||
398 | while (!err && rctx->left) { | |
399 | err = pre_crypt(req) ?: | |
400 | crypto_skcipher_decrypt(subreq) ?: | |
401 | post_crypt(req); | |
402 | ||
4e5b0ad5 | 403 | if (err == -EINPROGRESS || err == -EBUSY) |
700cb3f5 HX |
404 | return err; |
405 | } | |
64470f1b | 406 | |
700cb3f5 HX |
407 | exit_crypt(req); |
408 | return err; | |
64470f1b RS |
409 | } |
410 | ||
700cb3f5 | 411 | static void decrypt_done(struct crypto_async_request *areq, int err) |
64470f1b | 412 | { |
700cb3f5 HX |
413 | struct skcipher_request *req = areq->data; |
414 | struct skcipher_request *subreq; | |
415 | struct rctx *rctx; | |
416 | ||
417 | rctx = skcipher_request_ctx(req); | |
4702bbee HX |
418 | |
419 | if (err == -EINPROGRESS) { | |
420 | if (rctx->left != req->cryptlen) | |
421 | return; | |
422 | goto out; | |
423 | } | |
424 | ||
700cb3f5 HX |
425 | subreq = &rctx->subreq; |
426 | subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG; | |
427 | ||
428 | err = do_decrypt(req, err ?: post_crypt(req)); | |
429 | if (rctx->left) | |
430 | return; | |
64470f1b | 431 | |
4702bbee | 432 | out: |
700cb3f5 HX |
433 | skcipher_request_complete(req, err); |
434 | } | |
435 | ||
436 | static int decrypt(struct skcipher_request *req) | |
437 | { | |
438 | return do_decrypt(req, init_crypt(req, decrypt_done)); | |
64470f1b RS |
439 | } |
440 | ||
700cb3f5 | 441 | static int init_tfm(struct crypto_skcipher *tfm) |
64470f1b | 442 | { |
700cb3f5 HX |
443 | struct skcipher_instance *inst = skcipher_alg_instance(tfm); |
444 | struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); | |
445 | struct priv *ctx = crypto_skcipher_ctx(tfm); | |
446 | struct crypto_skcipher *cipher; | |
64470f1b | 447 | |
700cb3f5 | 448 | cipher = crypto_spawn_skcipher(spawn); |
2e306ee0 HX |
449 | if (IS_ERR(cipher)) |
450 | return PTR_ERR(cipher); | |
64470f1b | 451 | |
2e306ee0 | 452 | ctx->child = cipher; |
700cb3f5 HX |
453 | |
454 | crypto_skcipher_set_reqsize(tfm, crypto_skcipher_reqsize(cipher) + | |
455 | sizeof(struct rctx)); | |
456 | ||
64470f1b RS |
457 | return 0; |
458 | } | |
459 | ||
700cb3f5 | 460 | static void exit_tfm(struct crypto_skcipher *tfm) |
64470f1b | 461 | { |
700cb3f5 | 462 | struct priv *ctx = crypto_skcipher_ctx(tfm); |
171c0204 | 463 | |
217afccf EB |
464 | if (ctx->table) |
465 | gf128mul_free_64k(ctx->table); | |
700cb3f5 HX |
466 | crypto_free_skcipher(ctx->child); |
467 | } | |
468 | ||
469 | static void free(struct skcipher_instance *inst) | |
470 | { | |
471 | crypto_drop_skcipher(skcipher_instance_ctx(inst)); | |
472 | kfree(inst); | |
64470f1b RS |
473 | } |
474 | ||
700cb3f5 | 475 | static int create(struct crypto_template *tmpl, struct rtattr **tb) |
64470f1b | 476 | { |
700cb3f5 HX |
477 | struct crypto_skcipher_spawn *spawn; |
478 | struct skcipher_instance *inst; | |
479 | struct crypto_attr_type *algt; | |
480 | struct skcipher_alg *alg; | |
481 | const char *cipher_name; | |
482 | char ecb_name[CRYPTO_MAX_ALG_NAME]; | |
ebc610e5 HX |
483 | int err; |
484 | ||
700cb3f5 HX |
485 | algt = crypto_get_attr_type(tb); |
486 | if (IS_ERR(algt)) | |
487 | return PTR_ERR(algt); | |
488 | ||
489 | if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) | |
490 | return -EINVAL; | |
491 | ||
492 | cipher_name = crypto_attr_alg_name(tb[1]); | |
493 | if (IS_ERR(cipher_name)) | |
494 | return PTR_ERR(cipher_name); | |
495 | ||
496 | inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); | |
497 | if (!inst) | |
498 | return -ENOMEM; | |
499 | ||
500 | spawn = skcipher_instance_ctx(inst); | |
501 | ||
502 | crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst)); | |
503 | err = crypto_grab_skcipher(spawn, cipher_name, 0, | |
504 | crypto_requires_sync(algt->type, | |
505 | algt->mask)); | |
506 | if (err == -ENOENT) { | |
507 | err = -ENAMETOOLONG; | |
508 | if (snprintf(ecb_name, CRYPTO_MAX_ALG_NAME, "ecb(%s)", | |
509 | cipher_name) >= CRYPTO_MAX_ALG_NAME) | |
510 | goto err_free_inst; | |
511 | ||
512 | err = crypto_grab_skcipher(spawn, ecb_name, 0, | |
513 | crypto_requires_sync(algt->type, | |
514 | algt->mask)); | |
515 | } | |
516 | ||
ebc610e5 | 517 | if (err) |
700cb3f5 | 518 | goto err_free_inst; |
64470f1b | 519 | |
700cb3f5 | 520 | alg = crypto_skcipher_spawn_alg(spawn); |
64470f1b | 521 | |
700cb3f5 HX |
522 | err = -EINVAL; |
523 | if (alg->base.cra_blocksize != LRW_BLOCK_SIZE) | |
524 | goto err_drop_spawn; | |
64470f1b | 525 | |
700cb3f5 HX |
526 | if (crypto_skcipher_alg_ivsize(alg)) |
527 | goto err_drop_spawn; | |
64470f1b | 528 | |
700cb3f5 HX |
529 | err = crypto_inst_setname(skcipher_crypto_instance(inst), "lrw", |
530 | &alg->base); | |
531 | if (err) | |
532 | goto err_drop_spawn; | |
64470f1b | 533 | |
700cb3f5 HX |
534 | err = -EINVAL; |
535 | cipher_name = alg->base.cra_name; | |
64470f1b | 536 | |
700cb3f5 HX |
537 | /* Alas we screwed up the naming so we have to mangle the |
538 | * cipher name. | |
539 | */ | |
540 | if (!strncmp(cipher_name, "ecb(", 4)) { | |
541 | unsigned len; | |
64470f1b | 542 | |
700cb3f5 HX |
543 | len = strlcpy(ecb_name, cipher_name + 4, sizeof(ecb_name)); |
544 | if (len < 2 || len >= sizeof(ecb_name)) | |
545 | goto err_drop_spawn; | |
64470f1b | 546 | |
700cb3f5 HX |
547 | if (ecb_name[len - 1] != ')') |
548 | goto err_drop_spawn; | |
64470f1b | 549 | |
700cb3f5 | 550 | ecb_name[len - 1] = 0; |
64470f1b | 551 | |
700cb3f5 | 552 | if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, |
616129cc CJ |
553 | "lrw(%s)", ecb_name) >= CRYPTO_MAX_ALG_NAME) { |
554 | err = -ENAMETOOLONG; | |
555 | goto err_drop_spawn; | |
556 | } | |
d38efad2 CJ |
557 | } else |
558 | goto err_drop_spawn; | |
700cb3f5 HX |
559 | |
560 | inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; | |
561 | inst->alg.base.cra_priority = alg->base.cra_priority; | |
562 | inst->alg.base.cra_blocksize = LRW_BLOCK_SIZE; | |
563 | inst->alg.base.cra_alignmask = alg->base.cra_alignmask | | |
c778f96b | 564 | (__alignof__(__be32) - 1); |
700cb3f5 HX |
565 | |
566 | inst->alg.ivsize = LRW_BLOCK_SIZE; | |
567 | inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) + | |
568 | LRW_BLOCK_SIZE; | |
569 | inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) + | |
570 | LRW_BLOCK_SIZE; | |
571 | ||
572 | inst->alg.base.cra_ctxsize = sizeof(struct priv); | |
573 | ||
574 | inst->alg.init = init_tfm; | |
575 | inst->alg.exit = exit_tfm; | |
576 | ||
577 | inst->alg.setkey = setkey; | |
578 | inst->alg.encrypt = encrypt; | |
579 | inst->alg.decrypt = decrypt; | |
580 | ||
581 | inst->free = free; | |
582 | ||
583 | err = skcipher_register_instance(tmpl, inst); | |
584 | if (err) | |
585 | goto err_drop_spawn; | |
586 | ||
587 | out: | |
588 | return err; | |
589 | ||
590 | err_drop_spawn: | |
591 | crypto_drop_skcipher(spawn); | |
592 | err_free_inst: | |
64470f1b | 593 | kfree(inst); |
700cb3f5 | 594 | goto out; |
64470f1b RS |
595 | } |
596 | ||
597 | static struct crypto_template crypto_tmpl = { | |
598 | .name = "lrw", | |
700cb3f5 | 599 | .create = create, |
64470f1b RS |
600 | .module = THIS_MODULE, |
601 | }; | |
602 | ||
603 | static int __init crypto_module_init(void) | |
604 | { | |
605 | return crypto_register_template(&crypto_tmpl); | |
606 | } | |
607 | ||
608 | static void __exit crypto_module_exit(void) | |
609 | { | |
610 | crypto_unregister_template(&crypto_tmpl); | |
611 | } | |
612 | ||
613 | module_init(crypto_module_init); | |
614 | module_exit(crypto_module_exit); | |
615 | ||
616 | MODULE_LICENSE("GPL"); | |
617 | MODULE_DESCRIPTION("LRW block cipher mode"); | |
4943ba16 | 618 | MODULE_ALIAS_CRYPTO("lrw"); |