blob: 7830d304dff6f75d9464857fbab0592872657d37
1 | /* |
2 | * RSA padding templates. |
3 | * |
4 | * Copyright (c) 2015 Intel Corporation |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify it |
7 | * under the terms of the GNU General Public License as published by the Free |
8 | * Software Foundation; either version 2 of the License, or (at your option) |
9 | * any later version. |
10 | */ |
11 | |
12 | #include <crypto/algapi.h> |
13 | #include <crypto/akcipher.h> |
14 | #include <crypto/internal/akcipher.h> |
15 | #include <linux/err.h> |
16 | #include <linux/init.h> |
17 | #include <linux/kernel.h> |
18 | #include <linux/module.h> |
19 | #include <linux/random.h> |
20 | |
21 | /* |
22 | * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2]. |
23 | */ |
24 | static const u8 rsa_digest_info_md5[] = { |
25 | 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, |
26 | 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, /* OID */ |
27 | 0x05, 0x00, 0x04, 0x10 |
28 | }; |
29 | |
30 | static const u8 rsa_digest_info_sha1[] = { |
31 | 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, |
32 | 0x2b, 0x0e, 0x03, 0x02, 0x1a, |
33 | 0x05, 0x00, 0x04, 0x14 |
34 | }; |
35 | |
36 | static const u8 rsa_digest_info_rmd160[] = { |
37 | 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, |
38 | 0x2b, 0x24, 0x03, 0x02, 0x01, |
39 | 0x05, 0x00, 0x04, 0x14 |
40 | }; |
41 | |
42 | static const u8 rsa_digest_info_sha224[] = { |
43 | 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09, |
44 | 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, |
45 | 0x05, 0x00, 0x04, 0x1c |
46 | }; |
47 | |
48 | static const u8 rsa_digest_info_sha256[] = { |
49 | 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, |
50 | 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, |
51 | 0x05, 0x00, 0x04, 0x20 |
52 | }; |
53 | |
54 | static const u8 rsa_digest_info_sha384[] = { |
55 | 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, |
56 | 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02, |
57 | 0x05, 0x00, 0x04, 0x30 |
58 | }; |
59 | |
60 | static const u8 rsa_digest_info_sha512[] = { |
61 | 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09, |
62 | 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, |
63 | 0x05, 0x00, 0x04, 0x40 |
64 | }; |
65 | |
66 | static const struct rsa_asn1_template { |
67 | const char *name; |
68 | const u8 *data; |
69 | size_t size; |
70 | } rsa_asn1_templates[] = { |
71 | #define _(X) { #X, rsa_digest_info_##X, sizeof(rsa_digest_info_##X) } |
72 | _(md5), |
73 | _(sha1), |
74 | _(rmd160), |
75 | _(sha256), |
76 | _(sha384), |
77 | _(sha512), |
78 | _(sha224), |
79 | { NULL } |
80 | #undef _ |
81 | }; |
82 | |
83 | static const struct rsa_asn1_template *rsa_lookup_asn1(const char *name) |
84 | { |
85 | const struct rsa_asn1_template *p; |
86 | |
87 | for (p = rsa_asn1_templates; p->name; p++) |
88 | if (strcmp(name, p->name) == 0) |
89 | return p; |
90 | return NULL; |
91 | } |
92 | |
93 | struct pkcs1pad_ctx { |
94 | struct crypto_akcipher *child; |
95 | unsigned int key_size; |
96 | }; |
97 | |
98 | struct pkcs1pad_inst_ctx { |
99 | struct crypto_akcipher_spawn spawn; |
100 | const struct rsa_asn1_template *digest_info; |
101 | }; |
102 | |
103 | struct pkcs1pad_request { |
104 | struct scatterlist in_sg[2], out_sg[1]; |
105 | uint8_t *in_buf, *out_buf; |
106 | struct akcipher_request child_req; |
107 | }; |
108 | |
109 | static int pkcs1pad_set_pub_key(struct crypto_akcipher *tfm, const void *key, |
110 | unsigned int keylen) |
111 | { |
112 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
113 | int err; |
114 | |
115 | ctx->key_size = 0; |
116 | |
117 | err = crypto_akcipher_set_pub_key(ctx->child, key, keylen); |
118 | if (err) |
119 | return err; |
120 | |
121 | /* Find out new modulus size from rsa implementation */ |
122 | err = crypto_akcipher_maxsize(ctx->child); |
123 | if (err < 0) |
124 | return err; |
125 | |
126 | if (err > PAGE_SIZE) |
127 | return -ENOTSUPP; |
128 | |
129 | ctx->key_size = err; |
130 | return 0; |
131 | } |
132 | |
133 | static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key, |
134 | unsigned int keylen) |
135 | { |
136 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
137 | int err; |
138 | |
139 | ctx->key_size = 0; |
140 | |
141 | err = crypto_akcipher_set_priv_key(ctx->child, key, keylen); |
142 | if (err) |
143 | return err; |
144 | |
145 | /* Find out new modulus size from rsa implementation */ |
146 | err = crypto_akcipher_maxsize(ctx->child); |
147 | if (err < 0) |
148 | return err; |
149 | |
150 | if (err > PAGE_SIZE) |
151 | return -ENOTSUPP; |
152 | |
153 | ctx->key_size = err; |
154 | return 0; |
155 | } |
156 | |
157 | static int pkcs1pad_get_max_size(struct crypto_akcipher *tfm) |
158 | { |
159 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
160 | |
161 | /* |
162 | * The maximum destination buffer size for the encrypt/sign operations |
163 | * will be the same as for RSA, even though it's smaller for |
164 | * decrypt/verify. |
165 | */ |
166 | |
167 | return ctx->key_size ?: -EINVAL; |
168 | } |
169 | |
170 | static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len, |
171 | struct scatterlist *next) |
172 | { |
173 | int nsegs = next ? 2 : 1; |
174 | |
175 | sg_init_table(sg, nsegs); |
176 | sg_set_buf(sg, buf, len); |
177 | |
178 | if (next) |
179 | sg_chain(sg, nsegs, next); |
180 | } |
181 | |
182 | static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err) |
183 | { |
184 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
185 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
186 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
187 | unsigned int pad_len; |
188 | unsigned int len; |
189 | u8 *out_buf; |
190 | |
191 | if (err) |
192 | goto out; |
193 | |
194 | len = req_ctx->child_req.dst_len; |
195 | pad_len = ctx->key_size - len; |
196 | |
197 | /* Four billion to one */ |
198 | if (likely(!pad_len)) |
199 | goto out; |
200 | |
201 | out_buf = kzalloc(ctx->key_size, GFP_ATOMIC); |
202 | err = -ENOMEM; |
203 | if (!out_buf) |
204 | goto out; |
205 | |
206 | sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len), |
207 | out_buf + pad_len, len); |
208 | sg_copy_from_buffer(req->dst, |
209 | sg_nents_for_len(req->dst, ctx->key_size), |
210 | out_buf, ctx->key_size); |
211 | kzfree(out_buf); |
212 | |
213 | out: |
214 | req->dst_len = ctx->key_size; |
215 | |
216 | kfree(req_ctx->in_buf); |
217 | |
218 | return err; |
219 | } |
220 | |
221 | static void pkcs1pad_encrypt_sign_complete_cb( |
222 | struct crypto_async_request *child_async_req, int err) |
223 | { |
224 | struct akcipher_request *req = child_async_req->data; |
225 | struct crypto_async_request async_req; |
226 | |
227 | if (err == -EINPROGRESS) |
228 | return; |
229 | |
230 | async_req.data = req->base.data; |
231 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); |
232 | async_req.flags = child_async_req->flags; |
233 | req->base.complete(&async_req, |
234 | pkcs1pad_encrypt_sign_complete(req, err)); |
235 | } |
236 | |
237 | static int pkcs1pad_encrypt(struct akcipher_request *req) |
238 | { |
239 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
240 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
241 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
242 | int err; |
243 | unsigned int i, ps_end; |
244 | |
245 | if (!ctx->key_size) |
246 | return -EINVAL; |
247 | |
248 | if (req->src_len > ctx->key_size - 11) |
249 | return -EOVERFLOW; |
250 | |
251 | if (req->dst_len < ctx->key_size) { |
252 | req->dst_len = ctx->key_size; |
253 | return -EOVERFLOW; |
254 | } |
255 | |
256 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
257 | GFP_KERNEL); |
258 | if (!req_ctx->in_buf) |
259 | return -ENOMEM; |
260 | |
261 | ps_end = ctx->key_size - req->src_len - 2; |
262 | req_ctx->in_buf[0] = 0x02; |
263 | for (i = 1; i < ps_end; i++) |
264 | req_ctx->in_buf[i] = 1 + prandom_u32_max(255); |
265 | req_ctx->in_buf[ps_end] = 0x00; |
266 | |
267 | pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf, |
268 | ctx->key_size - 1 - req->src_len, req->src); |
269 | |
270 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
271 | if (!req_ctx->out_buf) { |
272 | kfree(req_ctx->in_buf); |
273 | return -ENOMEM; |
274 | } |
275 | |
276 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, |
277 | ctx->key_size, NULL); |
278 | |
279 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
280 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, |
281 | pkcs1pad_encrypt_sign_complete_cb, req); |
282 | |
283 | /* Reuse output buffer */ |
284 | akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg, |
285 | req->dst, ctx->key_size - 1, req->dst_len); |
286 | |
287 | err = crypto_akcipher_encrypt(&req_ctx->child_req); |
288 | if (err != -EINPROGRESS && |
289 | (err != -EBUSY || |
290 | !(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG))) |
291 | return pkcs1pad_encrypt_sign_complete(req, err); |
292 | |
293 | return err; |
294 | } |
295 | |
296 | static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err) |
297 | { |
298 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
299 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
300 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
301 | unsigned int dst_len; |
302 | unsigned int pos; |
303 | u8 *out_buf; |
304 | |
305 | if (err) |
306 | goto done; |
307 | |
308 | err = -EINVAL; |
309 | dst_len = req_ctx->child_req.dst_len; |
310 | if (dst_len < ctx->key_size - 1) |
311 | goto done; |
312 | |
313 | out_buf = req_ctx->out_buf; |
314 | if (dst_len == ctx->key_size) { |
315 | if (out_buf[0] != 0x00) |
316 | /* Decrypted value had no leading 0 byte */ |
317 | goto done; |
318 | |
319 | dst_len--; |
320 | out_buf++; |
321 | } |
322 | |
323 | if (out_buf[0] != 0x02) |
324 | goto done; |
325 | |
326 | for (pos = 1; pos < dst_len; pos++) |
327 | if (out_buf[pos] == 0x00) |
328 | break; |
329 | if (pos < 9 || pos == dst_len) |
330 | goto done; |
331 | pos++; |
332 | |
333 | err = 0; |
334 | |
335 | if (req->dst_len < dst_len - pos) |
336 | err = -EOVERFLOW; |
337 | req->dst_len = dst_len - pos; |
338 | |
339 | if (!err) |
340 | sg_copy_from_buffer(req->dst, |
341 | sg_nents_for_len(req->dst, req->dst_len), |
342 | out_buf + pos, req->dst_len); |
343 | |
344 | done: |
345 | kzfree(req_ctx->out_buf); |
346 | |
347 | return err; |
348 | } |
349 | |
350 | static void pkcs1pad_decrypt_complete_cb( |
351 | struct crypto_async_request *child_async_req, int err) |
352 | { |
353 | struct akcipher_request *req = child_async_req->data; |
354 | struct crypto_async_request async_req; |
355 | |
356 | if (err == -EINPROGRESS) |
357 | return; |
358 | |
359 | async_req.data = req->base.data; |
360 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); |
361 | async_req.flags = child_async_req->flags; |
362 | req->base.complete(&async_req, pkcs1pad_decrypt_complete(req, err)); |
363 | } |
364 | |
365 | static int pkcs1pad_decrypt(struct akcipher_request *req) |
366 | { |
367 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
368 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
369 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
370 | int err; |
371 | |
372 | if (!ctx->key_size || req->src_len != ctx->key_size) |
373 | return -EINVAL; |
374 | |
375 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
376 | if (!req_ctx->out_buf) |
377 | return -ENOMEM; |
378 | |
379 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, |
380 | ctx->key_size, NULL); |
381 | |
382 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
383 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, |
384 | pkcs1pad_decrypt_complete_cb, req); |
385 | |
386 | /* Reuse input buffer, output to a new buffer */ |
387 | akcipher_request_set_crypt(&req_ctx->child_req, req->src, |
388 | req_ctx->out_sg, req->src_len, |
389 | ctx->key_size); |
390 | |
391 | err = crypto_akcipher_decrypt(&req_ctx->child_req); |
392 | if (err != -EINPROGRESS && |
393 | (err != -EBUSY || |
394 | !(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG))) |
395 | return pkcs1pad_decrypt_complete(req, err); |
396 | |
397 | return err; |
398 | } |
399 | |
400 | static int pkcs1pad_sign(struct akcipher_request *req) |
401 | { |
402 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
403 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
404 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
405 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); |
406 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); |
407 | const struct rsa_asn1_template *digest_info = ictx->digest_info; |
408 | int err; |
409 | unsigned int ps_end, digest_size = 0; |
410 | |
411 | if (!ctx->key_size) |
412 | return -EINVAL; |
413 | |
414 | digest_size = digest_info->size; |
415 | |
416 | if (req->src_len + digest_size > ctx->key_size - 11) |
417 | return -EOVERFLOW; |
418 | |
419 | if (req->dst_len < ctx->key_size) { |
420 | req->dst_len = ctx->key_size; |
421 | return -EOVERFLOW; |
422 | } |
423 | |
424 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
425 | GFP_KERNEL); |
426 | if (!req_ctx->in_buf) |
427 | return -ENOMEM; |
428 | |
429 | ps_end = ctx->key_size - digest_size - req->src_len - 2; |
430 | req_ctx->in_buf[0] = 0x01; |
431 | memset(req_ctx->in_buf + 1, 0xff, ps_end - 1); |
432 | req_ctx->in_buf[ps_end] = 0x00; |
433 | |
434 | memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data, |
435 | digest_info->size); |
436 | |
437 | pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf, |
438 | ctx->key_size - 1 - req->src_len, req->src); |
439 | |
440 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
441 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, |
442 | pkcs1pad_encrypt_sign_complete_cb, req); |
443 | |
444 | /* Reuse output buffer */ |
445 | akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg, |
446 | req->dst, ctx->key_size - 1, req->dst_len); |
447 | |
448 | err = crypto_akcipher_sign(&req_ctx->child_req); |
449 | if (err != -EINPROGRESS && |
450 | (err != -EBUSY || |
451 | !(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG))) |
452 | return pkcs1pad_encrypt_sign_complete(req, err); |
453 | |
454 | return err; |
455 | } |
456 | |
457 | static int pkcs1pad_verify_complete(struct akcipher_request *req, int err) |
458 | { |
459 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
460 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
461 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
462 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); |
463 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); |
464 | const struct rsa_asn1_template *digest_info = ictx->digest_info; |
465 | unsigned int dst_len; |
466 | unsigned int pos; |
467 | u8 *out_buf; |
468 | |
469 | if (err) |
470 | goto done; |
471 | |
472 | err = -EINVAL; |
473 | dst_len = req_ctx->child_req.dst_len; |
474 | if (dst_len < ctx->key_size - 1) |
475 | goto done; |
476 | |
477 | out_buf = req_ctx->out_buf; |
478 | if (dst_len == ctx->key_size) { |
479 | if (out_buf[0] != 0x00) |
480 | /* Decrypted value had no leading 0 byte */ |
481 | goto done; |
482 | |
483 | dst_len--; |
484 | out_buf++; |
485 | } |
486 | |
487 | err = -EBADMSG; |
488 | if (out_buf[0] != 0x01) |
489 | goto done; |
490 | |
491 | for (pos = 1; pos < dst_len; pos++) |
492 | if (out_buf[pos] != 0xff) |
493 | break; |
494 | |
495 | if (pos < 9 || pos == dst_len || out_buf[pos] != 0x00) |
496 | goto done; |
497 | pos++; |
498 | |
499 | if (crypto_memneq(out_buf + pos, digest_info->data, digest_info->size)) |
500 | goto done; |
501 | |
502 | pos += digest_info->size; |
503 | |
504 | err = 0; |
505 | |
506 | if (req->dst_len < dst_len - pos) |
507 | err = -EOVERFLOW; |
508 | req->dst_len = dst_len - pos; |
509 | |
510 | if (!err) |
511 | sg_copy_from_buffer(req->dst, |
512 | sg_nents_for_len(req->dst, req->dst_len), |
513 | out_buf + pos, req->dst_len); |
514 | done: |
515 | kzfree(req_ctx->out_buf); |
516 | |
517 | return err; |
518 | } |
519 | |
520 | static void pkcs1pad_verify_complete_cb( |
521 | struct crypto_async_request *child_async_req, int err) |
522 | { |
523 | struct akcipher_request *req = child_async_req->data; |
524 | struct crypto_async_request async_req; |
525 | |
526 | if (err == -EINPROGRESS) |
527 | return; |
528 | |
529 | async_req.data = req->base.data; |
530 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); |
531 | async_req.flags = child_async_req->flags; |
532 | req->base.complete(&async_req, pkcs1pad_verify_complete(req, err)); |
533 | } |
534 | |
535 | /* |
536 | * The verify operation is here for completeness similar to the verification |
537 | * defined in RFC2313 section 10.2 except that block type 0 is not accepted, |
538 | * as in RFC2437. RFC2437 section 9.2 doesn't define any operation to |
539 | * retrieve the DigestInfo from a signature, instead the user is expected |
540 | * to call the sign operation to generate the expected signature and compare |
541 | * signatures instead of the message-digests. |
542 | */ |
543 | static int pkcs1pad_verify(struct akcipher_request *req) |
544 | { |
545 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); |
546 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
547 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); |
548 | int err; |
549 | |
550 | if (!ctx->key_size || req->src_len < ctx->key_size) |
551 | return -EINVAL; |
552 | |
553 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
554 | if (!req_ctx->out_buf) |
555 | return -ENOMEM; |
556 | |
557 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, |
558 | ctx->key_size, NULL); |
559 | |
560 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
561 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, |
562 | pkcs1pad_verify_complete_cb, req); |
563 | |
564 | /* Reuse input buffer, output to a new buffer */ |
565 | akcipher_request_set_crypt(&req_ctx->child_req, req->src, |
566 | req_ctx->out_sg, req->src_len, |
567 | ctx->key_size); |
568 | |
569 | err = crypto_akcipher_verify(&req_ctx->child_req); |
570 | if (err != -EINPROGRESS && |
571 | (err != -EBUSY || |
572 | !(req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG))) |
573 | return pkcs1pad_verify_complete(req, err); |
574 | |
575 | return err; |
576 | } |
577 | |
578 | static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm) |
579 | { |
580 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); |
581 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); |
582 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
583 | struct crypto_akcipher *child_tfm; |
584 | |
585 | child_tfm = crypto_spawn_akcipher(&ictx->spawn); |
586 | if (IS_ERR(child_tfm)) |
587 | return PTR_ERR(child_tfm); |
588 | |
589 | ctx->child = child_tfm; |
590 | return 0; |
591 | } |
592 | |
593 | static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm) |
594 | { |
595 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
596 | |
597 | crypto_free_akcipher(ctx->child); |
598 | } |
599 | |
600 | static void pkcs1pad_free(struct akcipher_instance *inst) |
601 | { |
602 | struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst); |
603 | struct crypto_akcipher_spawn *spawn = &ctx->spawn; |
604 | |
605 | crypto_drop_akcipher(spawn); |
606 | kfree(inst); |
607 | } |
608 | |
609 | static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb) |
610 | { |
611 | const struct rsa_asn1_template *digest_info; |
612 | struct crypto_attr_type *algt; |
613 | struct akcipher_instance *inst; |
614 | struct pkcs1pad_inst_ctx *ctx; |
615 | struct crypto_akcipher_spawn *spawn; |
616 | struct akcipher_alg *rsa_alg; |
617 | const char *rsa_alg_name; |
618 | const char *hash_name; |
619 | int err; |
620 | |
621 | algt = crypto_get_attr_type(tb); |
622 | if (IS_ERR(algt)) |
623 | return PTR_ERR(algt); |
624 | |
625 | if ((algt->type ^ CRYPTO_ALG_TYPE_AKCIPHER) & algt->mask) |
626 | return -EINVAL; |
627 | |
628 | rsa_alg_name = crypto_attr_alg_name(tb[1]); |
629 | if (IS_ERR(rsa_alg_name)) |
630 | return PTR_ERR(rsa_alg_name); |
631 | |
632 | hash_name = crypto_attr_alg_name(tb[2]); |
633 | if (IS_ERR(hash_name)) |
634 | return PTR_ERR(hash_name); |
635 | |
636 | digest_info = rsa_lookup_asn1(hash_name); |
637 | if (!digest_info) |
638 | return -EINVAL; |
639 | |
640 | inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); |
641 | if (!inst) |
642 | return -ENOMEM; |
643 | |
644 | ctx = akcipher_instance_ctx(inst); |
645 | spawn = &ctx->spawn; |
646 | ctx->digest_info = digest_info; |
647 | |
648 | crypto_set_spawn(&spawn->base, akcipher_crypto_instance(inst)); |
649 | err = crypto_grab_akcipher(spawn, rsa_alg_name, 0, |
650 | crypto_requires_sync(algt->type, algt->mask)); |
651 | if (err) |
652 | goto out_free_inst; |
653 | |
654 | rsa_alg = crypto_spawn_akcipher_alg(spawn); |
655 | |
656 | err = -ENAMETOOLONG; |
657 | |
658 | if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, |
659 | "pkcs1pad(%s,%s)", rsa_alg->base.cra_name, hash_name) >= |
660 | CRYPTO_MAX_ALG_NAME || |
661 | snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, |
662 | "pkcs1pad(%s,%s)", |
663 | rsa_alg->base.cra_driver_name, hash_name) >= |
664 | CRYPTO_MAX_ALG_NAME) |
665 | goto out_drop_alg; |
666 | |
667 | inst->alg.base.cra_flags = rsa_alg->base.cra_flags & CRYPTO_ALG_ASYNC; |
668 | inst->alg.base.cra_priority = rsa_alg->base.cra_priority; |
669 | inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx); |
670 | |
671 | inst->alg.init = pkcs1pad_init_tfm; |
672 | inst->alg.exit = pkcs1pad_exit_tfm; |
673 | |
674 | inst->alg.encrypt = pkcs1pad_encrypt; |
675 | inst->alg.decrypt = pkcs1pad_decrypt; |
676 | inst->alg.sign = pkcs1pad_sign; |
677 | inst->alg.verify = pkcs1pad_verify; |
678 | inst->alg.set_pub_key = pkcs1pad_set_pub_key; |
679 | inst->alg.set_priv_key = pkcs1pad_set_priv_key; |
680 | inst->alg.max_size = pkcs1pad_get_max_size; |
681 | inst->alg.reqsize = sizeof(struct pkcs1pad_request) + rsa_alg->reqsize; |
682 | |
683 | inst->free = pkcs1pad_free; |
684 | |
685 | err = akcipher_register_instance(tmpl, inst); |
686 | if (err) |
687 | goto out_drop_alg; |
688 | |
689 | return 0; |
690 | |
691 | out_drop_alg: |
692 | crypto_drop_akcipher(spawn); |
693 | out_free_inst: |
694 | kfree(inst); |
695 | return err; |
696 | } |
697 | |
698 | struct crypto_template rsa_pkcs1pad_tmpl = { |
699 | .name = "pkcs1pad", |
700 | .create = pkcs1pad_create, |
701 | .module = THIS_MODULE, |
702 | }; |
703 |