Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RSA padding templates.
4 *
5 * Copyright (c) 2015 Intel Corporation
6 */
7
8#include <crypto/algapi.h>
9#include <crypto/akcipher.h>
10#include <crypto/internal/akcipher.h>
11#include <crypto/internal/rsa.h>
12#include <linux/err.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/random.h>
17#include <linux/scatterlist.h>
18
19/*
20 * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2].
21 */
22static const u8 rsa_digest_info_md5[] = {
23 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08,
24 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, /* OID */
25 0x05, 0x00, 0x04, 0x10
26};
27
28static const u8 rsa_digest_info_sha1[] = {
29 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
30 0x2b, 0x0e, 0x03, 0x02, 0x1a,
31 0x05, 0x00, 0x04, 0x14
32};
33
34static const u8 rsa_digest_info_rmd160[] = {
35 0x30, 0x21, 0x30, 0x09, 0x06, 0x05,
36 0x2b, 0x24, 0x03, 0x02, 0x01,
37 0x05, 0x00, 0x04, 0x14
38};
39
40static const u8 rsa_digest_info_sha224[] = {
41 0x30, 0x2d, 0x30, 0x0d, 0x06, 0x09,
42 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04,
43 0x05, 0x00, 0x04, 0x1c
44};
45
46static const u8 rsa_digest_info_sha256[] = {
47 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
48 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01,
49 0x05, 0x00, 0x04, 0x20
50};
51
52static const u8 rsa_digest_info_sha384[] = {
53 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
54 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x02,
55 0x05, 0x00, 0x04, 0x30
56};
57
58static const u8 rsa_digest_info_sha512[] = {
59 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
60 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03,
61 0x05, 0x00, 0x04, 0x40
62};
63
64static const u8 rsa_digest_info_sha3_256[] = {
65 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09,
66 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x08,
67 0x05, 0x00, 0x04, 0x20
68};
69
70static const u8 rsa_digest_info_sha3_384[] = {
71 0x30, 0x41, 0x30, 0x0d, 0x06, 0x09,
72 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x09,
73 0x05, 0x00, 0x04, 0x30
74};
75
76static const u8 rsa_digest_info_sha3_512[] = {
77 0x30, 0x51, 0x30, 0x0d, 0x06, 0x09,
78 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x0A,
79 0x05, 0x00, 0x04, 0x40
80};
81
82static const struct rsa_asn1_template {
83 const char *name;
84 const u8 *data;
85 size_t size;
86} rsa_asn1_templates[] = {
87#define _(X) { #X, rsa_digest_info_##X, sizeof(rsa_digest_info_##X) }
88 _(md5),
89 _(sha1),
90 _(rmd160),
91 _(sha256),
92 _(sha384),
93 _(sha512),
94 _(sha224),
95#undef _
96#define _(X) { "sha3-" #X, rsa_digest_info_sha3_##X, sizeof(rsa_digest_info_sha3_##X) }
97 _(256),
98 _(384),
99 _(512),
100#undef _
101 { NULL }
102};
103
104static const struct rsa_asn1_template *rsa_lookup_asn1(const char *name)
105{
106 const struct rsa_asn1_template *p;
107
108 for (p = rsa_asn1_templates; p->name; p++)
109 if (strcmp(name, p->name) == 0)
110 return p;
111 return NULL;
112}
113
114struct pkcs1pad_ctx {
115 struct crypto_akcipher *child;
116 unsigned int key_size;
117};
118
119struct pkcs1pad_inst_ctx {
120 struct crypto_akcipher_spawn spawn;
121 const struct rsa_asn1_template *digest_info;
122};
123
124struct pkcs1pad_request {
125 struct scatterlist in_sg[2], out_sg[1];
126 uint8_t *in_buf, *out_buf;
127 struct akcipher_request child_req;
128};
129
130static int pkcs1pad_set_pub_key(struct crypto_akcipher *tfm, const void *key,
131 unsigned int keylen)
132{
133 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
134 int err;
135
136 ctx->key_size = 0;
137
138 err = crypto_akcipher_set_pub_key(ctx->child, key, keylen);
139 if (err)
140 return err;
141
142 /* Find out new modulus size from rsa implementation */
143 err = crypto_akcipher_maxsize(ctx->child);
144 if (err > PAGE_SIZE)
145 return -ENOTSUPP;
146
147 ctx->key_size = err;
148 return 0;
149}
150
151static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key,
152 unsigned int keylen)
153{
154 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
155 int err;
156
157 ctx->key_size = 0;
158
159 err = crypto_akcipher_set_priv_key(ctx->child, key, keylen);
160 if (err)
161 return err;
162
163 /* Find out new modulus size from rsa implementation */
164 err = crypto_akcipher_maxsize(ctx->child);
165 if (err > PAGE_SIZE)
166 return -ENOTSUPP;
167
168 ctx->key_size = err;
169 return 0;
170}
171
172static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm)
173{
174 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
175
176 /*
177 * The maximum destination buffer size for the encrypt/sign operations
178 * will be the same as for RSA, even though it's smaller for
179 * decrypt/verify.
180 */
181
182 return ctx->key_size;
183}
184
185static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len,
186 struct scatterlist *next)
187{
188 int nsegs = next ? 2 : 1;
189
190 sg_init_table(sg, nsegs);
191 sg_set_buf(sg, buf, len);
192
193 if (next)
194 sg_chain(sg, nsegs, next);
195}
196
197static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err)
198{
199 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
200 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
201 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
202 unsigned int pad_len;
203 unsigned int len;
204 u8 *out_buf;
205
206 if (err)
207 goto out;
208
209 len = req_ctx->child_req.dst_len;
210 pad_len = ctx->key_size - len;
211
212 /* Four billion to one */
213 if (likely(!pad_len))
214 goto out;
215
216 out_buf = kzalloc(ctx->key_size, GFP_ATOMIC);
217 err = -ENOMEM;
218 if (!out_buf)
219 goto out;
220
221 sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len),
222 out_buf + pad_len, len);
223 sg_copy_from_buffer(req->dst,
224 sg_nents_for_len(req->dst, ctx->key_size),
225 out_buf, ctx->key_size);
226 kfree_sensitive(out_buf);
227
228out:
229 req->dst_len = ctx->key_size;
230
231 kfree(req_ctx->in_buf);
232
233 return err;
234}
235
236static void pkcs1pad_encrypt_sign_complete_cb(void *data, int err)
237{
238 struct akcipher_request *req = data;
239
240 if (err == -EINPROGRESS)
241 goto out;
242
243 err = pkcs1pad_encrypt_sign_complete(req, err);
244
245out:
246 akcipher_request_complete(req, err);
247}
248
249static int pkcs1pad_encrypt(struct akcipher_request *req)
250{
251 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
252 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
253 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
254 int err;
255 unsigned int i, ps_end;
256
257 if (!ctx->key_size)
258 return -EINVAL;
259
260 if (req->src_len > ctx->key_size - 11)
261 return -EOVERFLOW;
262
263 if (req->dst_len < ctx->key_size) {
264 req->dst_len = ctx->key_size;
265 return -EOVERFLOW;
266 }
267
268 req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
269 GFP_KERNEL);
270 if (!req_ctx->in_buf)
271 return -ENOMEM;
272
273 ps_end = ctx->key_size - req->src_len - 2;
274 req_ctx->in_buf[0] = 0x02;
275 for (i = 1; i < ps_end; i++)
276 req_ctx->in_buf[i] = get_random_u32_inclusive(1, 255);
277 req_ctx->in_buf[ps_end] = 0x00;
278
279 pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
280 ctx->key_size - 1 - req->src_len, req->src);
281
282 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
283 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
284 pkcs1pad_encrypt_sign_complete_cb, req);
285
286 /* Reuse output buffer */
287 akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
288 req->dst, ctx->key_size - 1, req->dst_len);
289
290 err = crypto_akcipher_encrypt(&req_ctx->child_req);
291 if (err != -EINPROGRESS && err != -EBUSY)
292 return pkcs1pad_encrypt_sign_complete(req, err);
293
294 return err;
295}
296
297static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err)
298{
299 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
300 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
301 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
302 unsigned int dst_len;
303 unsigned int pos;
304 u8 *out_buf;
305
306 if (err)
307 goto done;
308
309 err = -EINVAL;
310 dst_len = req_ctx->child_req.dst_len;
311 if (dst_len < ctx->key_size - 1)
312 goto done;
313
314 out_buf = req_ctx->out_buf;
315 if (dst_len == ctx->key_size) {
316 if (out_buf[0] != 0x00)
317 /* Decrypted value had no leading 0 byte */
318 goto done;
319
320 dst_len--;
321 out_buf++;
322 }
323
324 if (out_buf[0] != 0x02)
325 goto done;
326
327 for (pos = 1; pos < dst_len; pos++)
328 if (out_buf[pos] == 0x00)
329 break;
330 if (pos < 9 || pos == dst_len)
331 goto done;
332 pos++;
333
334 err = 0;
335
336 if (req->dst_len < dst_len - pos)
337 err = -EOVERFLOW;
338 req->dst_len = dst_len - pos;
339
340 if (!err)
341 sg_copy_from_buffer(req->dst,
342 sg_nents_for_len(req->dst, req->dst_len),
343 out_buf + pos, req->dst_len);
344
345done:
346 kfree_sensitive(req_ctx->out_buf);
347
348 return err;
349}
350
351static void pkcs1pad_decrypt_complete_cb(void *data, int err)
352{
353 struct akcipher_request *req = data;
354
355 if (err == -EINPROGRESS)
356 goto out;
357
358 err = pkcs1pad_decrypt_complete(req, err);
359
360out:
361 akcipher_request_complete(req, err);
362}
363
364static int pkcs1pad_decrypt(struct akcipher_request *req)
365{
366 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
367 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
368 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
369 int err;
370
371 if (!ctx->key_size || req->src_len != ctx->key_size)
372 return -EINVAL;
373
374 req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
375 if (!req_ctx->out_buf)
376 return -ENOMEM;
377
378 pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
379 ctx->key_size, NULL);
380
381 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
382 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
383 pkcs1pad_decrypt_complete_cb, req);
384
385 /* Reuse input buffer, output to a new buffer */
386 akcipher_request_set_crypt(&req_ctx->child_req, req->src,
387 req_ctx->out_sg, req->src_len,
388 ctx->key_size);
389
390 err = crypto_akcipher_decrypt(&req_ctx->child_req);
391 if (err != -EINPROGRESS && err != -EBUSY)
392 return pkcs1pad_decrypt_complete(req, err);
393
394 return err;
395}
396
397static int pkcs1pad_sign(struct akcipher_request *req)
398{
399 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
400 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
401 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
402 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
403 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
404 const struct rsa_asn1_template *digest_info = ictx->digest_info;
405 int err;
406 unsigned int ps_end, digest_info_size = 0;
407
408 if (!ctx->key_size)
409 return -EINVAL;
410
411 if (digest_info)
412 digest_info_size = digest_info->size;
413
414 if (req->src_len + digest_info_size > ctx->key_size - 11)
415 return -EOVERFLOW;
416
417 if (req->dst_len < ctx->key_size) {
418 req->dst_len = ctx->key_size;
419 return -EOVERFLOW;
420 }
421
422 req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
423 GFP_KERNEL);
424 if (!req_ctx->in_buf)
425 return -ENOMEM;
426
427 ps_end = ctx->key_size - digest_info_size - req->src_len - 2;
428 req_ctx->in_buf[0] = 0x01;
429 memset(req_ctx->in_buf + 1, 0xff, ps_end - 1);
430 req_ctx->in_buf[ps_end] = 0x00;
431
432 if (digest_info)
433 memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data,
434 digest_info->size);
435
436 pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
437 ctx->key_size - 1 - req->src_len, req->src);
438
439 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
440 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
441 pkcs1pad_encrypt_sign_complete_cb, req);
442
443 /* Reuse output buffer */
444 akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
445 req->dst, ctx->key_size - 1, req->dst_len);
446
447 err = crypto_akcipher_decrypt(&req_ctx->child_req);
448 if (err != -EINPROGRESS && err != -EBUSY)
449 return pkcs1pad_encrypt_sign_complete(req, err);
450
451 return err;
452}
453
454static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
455{
456 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
457 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
458 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
459 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
460 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
461 const struct rsa_asn1_template *digest_info = ictx->digest_info;
462 const unsigned int sig_size = req->src_len;
463 const unsigned int digest_size = req->dst_len;
464 unsigned int dst_len;
465 unsigned int pos;
466 u8 *out_buf;
467
468 if (err)
469 goto done;
470
471 err = -EINVAL;
472 dst_len = req_ctx->child_req.dst_len;
473 if (dst_len < ctx->key_size - 1)
474 goto done;
475
476 out_buf = req_ctx->out_buf;
477 if (dst_len == ctx->key_size) {
478 if (out_buf[0] != 0x00)
479 /* Decrypted value had no leading 0 byte */
480 goto done;
481
482 dst_len--;
483 out_buf++;
484 }
485
486 err = -EBADMSG;
487 if (out_buf[0] != 0x01)
488 goto done;
489
490 for (pos = 1; pos < dst_len; pos++)
491 if (out_buf[pos] != 0xff)
492 break;
493
494 if (pos < 9 || pos == dst_len || out_buf[pos] != 0x00)
495 goto done;
496 pos++;
497
498 if (digest_info) {
499 if (digest_info->size > dst_len - pos)
500 goto done;
501 if (crypto_memneq(out_buf + pos, digest_info->data,
502 digest_info->size))
503 goto done;
504
505 pos += digest_info->size;
506 }
507
508 err = 0;
509
510 if (digest_size != dst_len - pos) {
511 err = -EKEYREJECTED;
512 req->dst_len = dst_len - pos;
513 goto done;
514 }
515 /* Extract appended digest. */
516 sg_pcopy_to_buffer(req->src,
517 sg_nents_for_len(req->src, sig_size + digest_size),
518 req_ctx->out_buf + ctx->key_size,
519 digest_size, sig_size);
520 /* Do the actual verification step. */
521 if (memcmp(req_ctx->out_buf + ctx->key_size, out_buf + pos,
522 digest_size) != 0)
523 err = -EKEYREJECTED;
524done:
525 kfree_sensitive(req_ctx->out_buf);
526
527 return err;
528}
529
530static void pkcs1pad_verify_complete_cb(void *data, int err)
531{
532 struct akcipher_request *req = data;
533
534 if (err == -EINPROGRESS)
535 goto out;
536
537 err = pkcs1pad_verify_complete(req, err);
538
539out:
540 akcipher_request_complete(req, err);
541}
542
543/*
544 * The verify operation is here for completeness similar to the verification
545 * defined in RFC2313 section 10.2 except that block type 0 is not accepted,
546 * as in RFC2437. RFC2437 section 9.2 doesn't define any operation to
547 * retrieve the DigestInfo from a signature, instead the user is expected
548 * to call the sign operation to generate the expected signature and compare
549 * signatures instead of the message-digests.
550 */
551static int pkcs1pad_verify(struct akcipher_request *req)
552{
553 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
554 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
555 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
556 const unsigned int sig_size = req->src_len;
557 const unsigned int digest_size = req->dst_len;
558 int err;
559
560 if (WARN_ON(req->dst) || WARN_ON(!digest_size) ||
561 !ctx->key_size || sig_size != ctx->key_size)
562 return -EINVAL;
563
564 req_ctx->out_buf = kmalloc(ctx->key_size + digest_size, GFP_KERNEL);
565 if (!req_ctx->out_buf)
566 return -ENOMEM;
567
568 pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
569 ctx->key_size, NULL);
570
571 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
572 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
573 pkcs1pad_verify_complete_cb, req);
574
575 /* Reuse input buffer, output to a new buffer */
576 akcipher_request_set_crypt(&req_ctx->child_req, req->src,
577 req_ctx->out_sg, sig_size, ctx->key_size);
578
579 err = crypto_akcipher_encrypt(&req_ctx->child_req);
580 if (err != -EINPROGRESS && err != -EBUSY)
581 return pkcs1pad_verify_complete(req, err);
582
583 return err;
584}
585
586static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm)
587{
588 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
589 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
590 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
591 struct crypto_akcipher *child_tfm;
592
593 child_tfm = crypto_spawn_akcipher(&ictx->spawn);
594 if (IS_ERR(child_tfm))
595 return PTR_ERR(child_tfm);
596
597 ctx->child = child_tfm;
598
599 akcipher_set_reqsize(tfm, sizeof(struct pkcs1pad_request) +
600 crypto_akcipher_reqsize(child_tfm));
601
602 return 0;
603}
604
605static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm)
606{
607 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
608
609 crypto_free_akcipher(ctx->child);
610}
611
612static void pkcs1pad_free(struct akcipher_instance *inst)
613{
614 struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst);
615 struct crypto_akcipher_spawn *spawn = &ctx->spawn;
616
617 crypto_drop_akcipher(spawn);
618 kfree(inst);
619}
620
621static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
622{
623 u32 mask;
624 struct akcipher_instance *inst;
625 struct pkcs1pad_inst_ctx *ctx;
626 struct akcipher_alg *rsa_alg;
627 const char *hash_name;
628 int err;
629
630 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AKCIPHER, &mask);
631 if (err)
632 return err;
633
634 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
635 if (!inst)
636 return -ENOMEM;
637
638 ctx = akcipher_instance_ctx(inst);
639
640 err = crypto_grab_akcipher(&ctx->spawn, akcipher_crypto_instance(inst),
641 crypto_attr_alg_name(tb[1]), 0, mask);
642 if (err)
643 goto err_free_inst;
644
645 rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn);
646
647 if (strcmp(rsa_alg->base.cra_name, "rsa") != 0) {
648 err = -EINVAL;
649 goto err_free_inst;
650 }
651
652 err = -ENAMETOOLONG;
653 hash_name = crypto_attr_alg_name(tb[2]);
654 if (IS_ERR(hash_name)) {
655 if (snprintf(inst->alg.base.cra_name,
656 CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
657 rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
658 goto err_free_inst;
659
660 if (snprintf(inst->alg.base.cra_driver_name,
661 CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)",
662 rsa_alg->base.cra_driver_name) >=
663 CRYPTO_MAX_ALG_NAME)
664 goto err_free_inst;
665 } else {
666 ctx->digest_info = rsa_lookup_asn1(hash_name);
667 if (!ctx->digest_info) {
668 err = -EINVAL;
669 goto err_free_inst;
670 }
671
672 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
673 "pkcs1pad(%s,%s)", rsa_alg->base.cra_name,
674 hash_name) >= CRYPTO_MAX_ALG_NAME)
675 goto err_free_inst;
676
677 if (snprintf(inst->alg.base.cra_driver_name,
678 CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s,%s)",
679 rsa_alg->base.cra_driver_name,
680 hash_name) >= CRYPTO_MAX_ALG_NAME)
681 goto err_free_inst;
682 }
683
684 inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
685 inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx);
686
687 inst->alg.init = pkcs1pad_init_tfm;
688 inst->alg.exit = pkcs1pad_exit_tfm;
689
690 inst->alg.encrypt = pkcs1pad_encrypt;
691 inst->alg.decrypt = pkcs1pad_decrypt;
692 inst->alg.sign = pkcs1pad_sign;
693 inst->alg.verify = pkcs1pad_verify;
694 inst->alg.set_pub_key = pkcs1pad_set_pub_key;
695 inst->alg.set_priv_key = pkcs1pad_set_priv_key;
696 inst->alg.max_size = pkcs1pad_get_max_size;
697
698 inst->free = pkcs1pad_free;
699
700 err = akcipher_register_instance(tmpl, inst);
701 if (err) {
702err_free_inst:
703 pkcs1pad_free(inst);
704 }
705 return err;
706}
707
708struct crypto_template rsa_pkcs1pad_tmpl = {
709 .name = "pkcs1pad",
710 .create = pkcs1pad_create,
711 .module = THIS_MODULE,
712};
713
714MODULE_ALIAS_CRYPTO("pkcs1pad");
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 */
24static 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
30static 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
36static 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
42static 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
48static 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
54static 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
60static 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
66static 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
83static 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
93struct pkcs1pad_ctx {
94 struct crypto_akcipher *child;
95 unsigned int key_size;
96};
97
98struct pkcs1pad_inst_ctx {
99 struct crypto_akcipher_spawn spawn;
100 const struct rsa_asn1_template *digest_info;
101};
102
103struct 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
109static 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 > PAGE_SIZE)
124 return -ENOTSUPP;
125
126 ctx->key_size = err;
127 return 0;
128}
129
130static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key,
131 unsigned int keylen)
132{
133 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
134 int err;
135
136 ctx->key_size = 0;
137
138 err = crypto_akcipher_set_priv_key(ctx->child, key, keylen);
139 if (err)
140 return err;
141
142 /* Find out new modulus size from rsa implementation */
143 err = crypto_akcipher_maxsize(ctx->child);
144 if (err > PAGE_SIZE)
145 return -ENOTSUPP;
146
147 ctx->key_size = err;
148 return 0;
149}
150
151static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm)
152{
153 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
154
155 /*
156 * The maximum destination buffer size for the encrypt/sign operations
157 * will be the same as for RSA, even though it's smaller for
158 * decrypt/verify.
159 */
160
161 return ctx->key_size;
162}
163
164static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len,
165 struct scatterlist *next)
166{
167 int nsegs = next ? 2 : 1;
168
169 sg_init_table(sg, nsegs);
170 sg_set_buf(sg, buf, len);
171
172 if (next)
173 sg_chain(sg, nsegs, next);
174}
175
176static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err)
177{
178 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
179 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
180 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
181 unsigned int pad_len;
182 unsigned int len;
183 u8 *out_buf;
184
185 if (err)
186 goto out;
187
188 len = req_ctx->child_req.dst_len;
189 pad_len = ctx->key_size - len;
190
191 /* Four billion to one */
192 if (likely(!pad_len))
193 goto out;
194
195 out_buf = kzalloc(ctx->key_size, GFP_KERNEL);
196 err = -ENOMEM;
197 if (!out_buf)
198 goto out;
199
200 sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len),
201 out_buf + pad_len, len);
202 sg_copy_from_buffer(req->dst,
203 sg_nents_for_len(req->dst, ctx->key_size),
204 out_buf, ctx->key_size);
205 kzfree(out_buf);
206
207out:
208 req->dst_len = ctx->key_size;
209
210 kfree(req_ctx->in_buf);
211
212 return err;
213}
214
215static void pkcs1pad_encrypt_sign_complete_cb(
216 struct crypto_async_request *child_async_req, int err)
217{
218 struct akcipher_request *req = child_async_req->data;
219 struct crypto_async_request async_req;
220
221 if (err == -EINPROGRESS)
222 return;
223
224 async_req.data = req->base.data;
225 async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req));
226 async_req.flags = child_async_req->flags;
227 req->base.complete(&async_req,
228 pkcs1pad_encrypt_sign_complete(req, err));
229}
230
231static int pkcs1pad_encrypt(struct akcipher_request *req)
232{
233 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
234 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
235 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
236 int err;
237 unsigned int i, ps_end;
238
239 if (!ctx->key_size)
240 return -EINVAL;
241
242 if (req->src_len > ctx->key_size - 11)
243 return -EOVERFLOW;
244
245 if (req->dst_len < ctx->key_size) {
246 req->dst_len = ctx->key_size;
247 return -EOVERFLOW;
248 }
249
250 req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
251 GFP_KERNEL);
252 if (!req_ctx->in_buf)
253 return -ENOMEM;
254
255 ps_end = ctx->key_size - req->src_len - 2;
256 req_ctx->in_buf[0] = 0x02;
257 for (i = 1; i < ps_end; i++)
258 req_ctx->in_buf[i] = 1 + prandom_u32_max(255);
259 req_ctx->in_buf[ps_end] = 0x00;
260
261 pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
262 ctx->key_size - 1 - req->src_len, req->src);
263
264 req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
265 if (!req_ctx->out_buf) {
266 kfree(req_ctx->in_buf);
267 return -ENOMEM;
268 }
269
270 pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
271 ctx->key_size, NULL);
272
273 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
274 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
275 pkcs1pad_encrypt_sign_complete_cb, req);
276
277 /* Reuse output buffer */
278 akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
279 req->dst, ctx->key_size - 1, req->dst_len);
280
281 err = crypto_akcipher_encrypt(&req_ctx->child_req);
282 if (err != -EINPROGRESS && err != -EBUSY)
283 return pkcs1pad_encrypt_sign_complete(req, err);
284
285 return err;
286}
287
288static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err)
289{
290 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
291 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
292 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
293 unsigned int dst_len;
294 unsigned int pos;
295 u8 *out_buf;
296
297 if (err)
298 goto done;
299
300 err = -EINVAL;
301 dst_len = req_ctx->child_req.dst_len;
302 if (dst_len < ctx->key_size - 1)
303 goto done;
304
305 out_buf = req_ctx->out_buf;
306 if (dst_len == ctx->key_size) {
307 if (out_buf[0] != 0x00)
308 /* Decrypted value had no leading 0 byte */
309 goto done;
310
311 dst_len--;
312 out_buf++;
313 }
314
315 if (out_buf[0] != 0x02)
316 goto done;
317
318 for (pos = 1; pos < dst_len; pos++)
319 if (out_buf[pos] == 0x00)
320 break;
321 if (pos < 9 || pos == dst_len)
322 goto done;
323 pos++;
324
325 err = 0;
326
327 if (req->dst_len < dst_len - pos)
328 err = -EOVERFLOW;
329 req->dst_len = dst_len - pos;
330
331 if (!err)
332 sg_copy_from_buffer(req->dst,
333 sg_nents_for_len(req->dst, req->dst_len),
334 out_buf + pos, req->dst_len);
335
336done:
337 kzfree(req_ctx->out_buf);
338
339 return err;
340}
341
342static void pkcs1pad_decrypt_complete_cb(
343 struct crypto_async_request *child_async_req, int err)
344{
345 struct akcipher_request *req = child_async_req->data;
346 struct crypto_async_request async_req;
347
348 if (err == -EINPROGRESS)
349 return;
350
351 async_req.data = req->base.data;
352 async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req));
353 async_req.flags = child_async_req->flags;
354 req->base.complete(&async_req, pkcs1pad_decrypt_complete(req, err));
355}
356
357static int pkcs1pad_decrypt(struct akcipher_request *req)
358{
359 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
360 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
361 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
362 int err;
363
364 if (!ctx->key_size || req->src_len != ctx->key_size)
365 return -EINVAL;
366
367 req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
368 if (!req_ctx->out_buf)
369 return -ENOMEM;
370
371 pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
372 ctx->key_size, NULL);
373
374 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
375 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
376 pkcs1pad_decrypt_complete_cb, req);
377
378 /* Reuse input buffer, output to a new buffer */
379 akcipher_request_set_crypt(&req_ctx->child_req, req->src,
380 req_ctx->out_sg, req->src_len,
381 ctx->key_size);
382
383 err = crypto_akcipher_decrypt(&req_ctx->child_req);
384 if (err != -EINPROGRESS && err != -EBUSY)
385 return pkcs1pad_decrypt_complete(req, err);
386
387 return err;
388}
389
390static int pkcs1pad_sign(struct akcipher_request *req)
391{
392 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
393 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
394 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
395 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
396 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
397 const struct rsa_asn1_template *digest_info = ictx->digest_info;
398 int err;
399 unsigned int ps_end, digest_size = 0;
400
401 if (!ctx->key_size)
402 return -EINVAL;
403
404 digest_size = digest_info->size;
405
406 if (req->src_len + digest_size > ctx->key_size - 11)
407 return -EOVERFLOW;
408
409 if (req->dst_len < ctx->key_size) {
410 req->dst_len = ctx->key_size;
411 return -EOVERFLOW;
412 }
413
414 req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len,
415 GFP_KERNEL);
416 if (!req_ctx->in_buf)
417 return -ENOMEM;
418
419 ps_end = ctx->key_size - digest_size - req->src_len - 2;
420 req_ctx->in_buf[0] = 0x01;
421 memset(req_ctx->in_buf + 1, 0xff, ps_end - 1);
422 req_ctx->in_buf[ps_end] = 0x00;
423
424 memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data,
425 digest_info->size);
426
427 pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf,
428 ctx->key_size - 1 - req->src_len, req->src);
429
430 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
431 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
432 pkcs1pad_encrypt_sign_complete_cb, req);
433
434 /* Reuse output buffer */
435 akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg,
436 req->dst, ctx->key_size - 1, req->dst_len);
437
438 err = crypto_akcipher_sign(&req_ctx->child_req);
439 if (err != -EINPROGRESS && err != -EBUSY)
440 return pkcs1pad_encrypt_sign_complete(req, err);
441
442 return err;
443}
444
445static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
446{
447 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
448 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
449 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
450 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
451 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
452 const struct rsa_asn1_template *digest_info = ictx->digest_info;
453 unsigned int dst_len;
454 unsigned int pos;
455 u8 *out_buf;
456
457 if (err)
458 goto done;
459
460 err = -EINVAL;
461 dst_len = req_ctx->child_req.dst_len;
462 if (dst_len < ctx->key_size - 1)
463 goto done;
464
465 out_buf = req_ctx->out_buf;
466 if (dst_len == ctx->key_size) {
467 if (out_buf[0] != 0x00)
468 /* Decrypted value had no leading 0 byte */
469 goto done;
470
471 dst_len--;
472 out_buf++;
473 }
474
475 err = -EBADMSG;
476 if (out_buf[0] != 0x01)
477 goto done;
478
479 for (pos = 1; pos < dst_len; pos++)
480 if (out_buf[pos] != 0xff)
481 break;
482
483 if (pos < 9 || pos == dst_len || out_buf[pos] != 0x00)
484 goto done;
485 pos++;
486
487 if (crypto_memneq(out_buf + pos, digest_info->data, digest_info->size))
488 goto done;
489
490 pos += digest_info->size;
491
492 err = 0;
493
494 if (req->dst_len < dst_len - pos)
495 err = -EOVERFLOW;
496 req->dst_len = dst_len - pos;
497
498 if (!err)
499 sg_copy_from_buffer(req->dst,
500 sg_nents_for_len(req->dst, req->dst_len),
501 out_buf + pos, req->dst_len);
502done:
503 kzfree(req_ctx->out_buf);
504
505 return err;
506}
507
508static void pkcs1pad_verify_complete_cb(
509 struct crypto_async_request *child_async_req, int err)
510{
511 struct akcipher_request *req = child_async_req->data;
512 struct crypto_async_request async_req;
513
514 if (err == -EINPROGRESS)
515 return;
516
517 async_req.data = req->base.data;
518 async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req));
519 async_req.flags = child_async_req->flags;
520 req->base.complete(&async_req, pkcs1pad_verify_complete(req, err));
521}
522
523/*
524 * The verify operation is here for completeness similar to the verification
525 * defined in RFC2313 section 10.2 except that block type 0 is not accepted,
526 * as in RFC2437. RFC2437 section 9.2 doesn't define any operation to
527 * retrieve the DigestInfo from a signature, instead the user is expected
528 * to call the sign operation to generate the expected signature and compare
529 * signatures instead of the message-digests.
530 */
531static int pkcs1pad_verify(struct akcipher_request *req)
532{
533 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
534 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
535 struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
536 int err;
537
538 if (!ctx->key_size || req->src_len < ctx->key_size)
539 return -EINVAL;
540
541 req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL);
542 if (!req_ctx->out_buf)
543 return -ENOMEM;
544
545 pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf,
546 ctx->key_size, NULL);
547
548 akcipher_request_set_tfm(&req_ctx->child_req, ctx->child);
549 akcipher_request_set_callback(&req_ctx->child_req, req->base.flags,
550 pkcs1pad_verify_complete_cb, req);
551
552 /* Reuse input buffer, output to a new buffer */
553 akcipher_request_set_crypt(&req_ctx->child_req, req->src,
554 req_ctx->out_sg, req->src_len,
555 ctx->key_size);
556
557 err = crypto_akcipher_verify(&req_ctx->child_req);
558 if (err != -EINPROGRESS && err != -EBUSY)
559 return pkcs1pad_verify_complete(req, err);
560
561 return err;
562}
563
564static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm)
565{
566 struct akcipher_instance *inst = akcipher_alg_instance(tfm);
567 struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
568 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
569 struct crypto_akcipher *child_tfm;
570
571 child_tfm = crypto_spawn_akcipher(&ictx->spawn);
572 if (IS_ERR(child_tfm))
573 return PTR_ERR(child_tfm);
574
575 ctx->child = child_tfm;
576 return 0;
577}
578
579static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm)
580{
581 struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
582
583 crypto_free_akcipher(ctx->child);
584}
585
586static void pkcs1pad_free(struct akcipher_instance *inst)
587{
588 struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst);
589 struct crypto_akcipher_spawn *spawn = &ctx->spawn;
590
591 crypto_drop_akcipher(spawn);
592 kfree(inst);
593}
594
595static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb)
596{
597 const struct rsa_asn1_template *digest_info;
598 struct crypto_attr_type *algt;
599 struct akcipher_instance *inst;
600 struct pkcs1pad_inst_ctx *ctx;
601 struct crypto_akcipher_spawn *spawn;
602 struct akcipher_alg *rsa_alg;
603 const char *rsa_alg_name;
604 const char *hash_name;
605 int err;
606
607 algt = crypto_get_attr_type(tb);
608 if (IS_ERR(algt))
609 return PTR_ERR(algt);
610
611 if ((algt->type ^ CRYPTO_ALG_TYPE_AKCIPHER) & algt->mask)
612 return -EINVAL;
613
614 rsa_alg_name = crypto_attr_alg_name(tb[1]);
615 if (IS_ERR(rsa_alg_name))
616 return PTR_ERR(rsa_alg_name);
617
618 hash_name = crypto_attr_alg_name(tb[2]);
619 if (IS_ERR(hash_name))
620 return PTR_ERR(hash_name);
621
622 digest_info = rsa_lookup_asn1(hash_name);
623 if (!digest_info)
624 return -EINVAL;
625
626 inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
627 if (!inst)
628 return -ENOMEM;
629
630 ctx = akcipher_instance_ctx(inst);
631 spawn = &ctx->spawn;
632 ctx->digest_info = digest_info;
633
634 crypto_set_spawn(&spawn->base, akcipher_crypto_instance(inst));
635 err = crypto_grab_akcipher(spawn, rsa_alg_name, 0,
636 crypto_requires_sync(algt->type, algt->mask));
637 if (err)
638 goto out_free_inst;
639
640 rsa_alg = crypto_spawn_akcipher_alg(spawn);
641
642 err = -ENAMETOOLONG;
643
644 if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
645 "pkcs1pad(%s,%s)", rsa_alg->base.cra_name, hash_name) >=
646 CRYPTO_MAX_ALG_NAME ||
647 snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
648 "pkcs1pad(%s,%s)",
649 rsa_alg->base.cra_driver_name, hash_name) >=
650 CRYPTO_MAX_ALG_NAME)
651 goto out_drop_alg;
652
653 inst->alg.base.cra_flags = rsa_alg->base.cra_flags & CRYPTO_ALG_ASYNC;
654 inst->alg.base.cra_priority = rsa_alg->base.cra_priority;
655 inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx);
656
657 inst->alg.init = pkcs1pad_init_tfm;
658 inst->alg.exit = pkcs1pad_exit_tfm;
659
660 inst->alg.encrypt = pkcs1pad_encrypt;
661 inst->alg.decrypt = pkcs1pad_decrypt;
662 inst->alg.sign = pkcs1pad_sign;
663 inst->alg.verify = pkcs1pad_verify;
664 inst->alg.set_pub_key = pkcs1pad_set_pub_key;
665 inst->alg.set_priv_key = pkcs1pad_set_priv_key;
666 inst->alg.max_size = pkcs1pad_get_max_size;
667 inst->alg.reqsize = sizeof(struct pkcs1pad_request) + rsa_alg->reqsize;
668
669 inst->free = pkcs1pad_free;
670
671 err = akcipher_register_instance(tmpl, inst);
672 if (err)
673 goto out_drop_alg;
674
675 return 0;
676
677out_drop_alg:
678 crypto_drop_akcipher(spawn);
679out_free_inst:
680 kfree(inst);
681 return err;
682}
683
684struct crypto_template rsa_pkcs1pad_tmpl = {
685 .name = "pkcs1pad",
686 .create = pkcs1pad_create,
687 .module = THIS_MODULE,
688};