Commit | Line | Data |
---|---|---|
3d5b1ecd AZ |
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 | ||
a49de377 TS |
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 | ||
3d5b1ecd AZ |
93 | struct pkcs1pad_ctx { |
94 | struct crypto_akcipher *child; | |
3d5b1ecd AZ |
95 | unsigned int key_size; |
96 | }; | |
97 | ||
a49de377 TS |
98 | struct pkcs1pad_inst_ctx { |
99 | struct crypto_akcipher_spawn spawn; | |
c0d20d22 | 100 | const struct rsa_asn1_template *digest_info; |
a49de377 TS |
101 | }; |
102 | ||
3d5b1ecd | 103 | struct pkcs1pad_request { |
0f2c8319 | 104 | struct scatterlist in_sg[2], out_sg[1]; |
3d5b1ecd | 105 | uint8_t *in_buf, *out_buf; |
a6d7bfd0 | 106 | struct akcipher_request child_req; |
3d5b1ecd AZ |
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); | |
73f79189 HX |
113 | int err; |
114 | ||
115 | ctx->key_size = 0; | |
3d5b1ecd AZ |
116 | |
117 | err = crypto_akcipher_set_pub_key(ctx->child, key, keylen); | |
73f79189 HX |
118 | if (err) |
119 | return err; | |
3d5b1ecd | 120 | |
73f79189 HX |
121 | /* Find out new modulus size from rsa implementation */ |
122 | err = crypto_akcipher_maxsize(ctx->child); | |
73f79189 HX |
123 | if (err > PAGE_SIZE) |
124 | return -ENOTSUPP; | |
3d5b1ecd | 125 | |
73f79189 HX |
126 | ctx->key_size = err; |
127 | return 0; | |
3d5b1ecd AZ |
128 | } |
129 | ||
130 | static 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); | |
73f79189 HX |
134 | int err; |
135 | ||
136 | ctx->key_size = 0; | |
3d5b1ecd AZ |
137 | |
138 | err = crypto_akcipher_set_priv_key(ctx->child, key, keylen); | |
73f79189 HX |
139 | if (err) |
140 | return err; | |
3d5b1ecd | 141 | |
73f79189 HX |
142 | /* Find out new modulus size from rsa implementation */ |
143 | err = crypto_akcipher_maxsize(ctx->child); | |
73f79189 HX |
144 | if (err > PAGE_SIZE) |
145 | return -ENOTSUPP; | |
3d5b1ecd | 146 | |
73f79189 HX |
147 | ctx->key_size = err; |
148 | return 0; | |
3d5b1ecd AZ |
149 | } |
150 | ||
543de102 | 151 | static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm) |
3d5b1ecd AZ |
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 | ||
543de102 | 161 | return ctx->key_size; |
3d5b1ecd AZ |
162 | } |
163 | ||
164 | static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len, | |
165 | struct scatterlist *next) | |
166 | { | |
0f2c8319 HX |
167 | int nsegs = next ? 2 : 1; |
168 | ||
169 | sg_init_table(sg, nsegs); | |
170 | sg_set_buf(sg, buf, len); | |
3d5b1ecd AZ |
171 | |
172 | if (next) | |
173 | sg_chain(sg, nsegs, next); | |
174 | } | |
175 | ||
176 | static 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); | |
d858b071 HX |
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 | ||
1ca28098 | 195 | out_buf = kzalloc(ctx->key_size, GFP_KERNEL); |
d858b071 HX |
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 | ||
207 | out: | |
3d5b1ecd AZ |
208 | req->dst_len = ctx->key_size; |
209 | ||
210 | kfree(req_ctx->in_buf); | |
3d5b1ecd AZ |
211 | |
212 | return err; | |
213 | } | |
214 | ||
215 | static 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 | ||
231 | static 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 | ||
3d5b1ecd | 250 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
3a32ce50 | 251 | GFP_KERNEL); |
3d5b1ecd AZ |
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 | ||
3a32ce50 | 264 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
3d5b1ecd AZ |
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 | ||
d858b071 HX |
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 | ||
3d5b1ecd | 281 | err = crypto_akcipher_encrypt(&req_ctx->child_req); |
4e5b0ad5 | 282 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
283 | return pkcs1pad_encrypt_sign_complete(req, err); |
284 | ||
285 | return err; | |
286 | } | |
287 | ||
288 | static 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); | |
0cf43f50 | 293 | unsigned int dst_len; |
3d5b1ecd | 294 | unsigned int pos; |
0cf43f50 | 295 | u8 *out_buf; |
3d5b1ecd AZ |
296 | |
297 | if (err) | |
298 | goto done; | |
299 | ||
0cf43f50 HX |
300 | err = -EINVAL; |
301 | dst_len = req_ctx->child_req.dst_len; | |
302 | if (dst_len < ctx->key_size - 1) | |
3d5b1ecd | 303 | goto done; |
0cf43f50 HX |
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++; | |
3d5b1ecd AZ |
313 | } |
314 | ||
0cf43f50 | 315 | if (out_buf[0] != 0x02) |
3d5b1ecd | 316 | goto done; |
0cf43f50 HX |
317 | |
318 | for (pos = 1; pos < dst_len; pos++) | |
319 | if (out_buf[pos] == 0x00) | |
3d5b1ecd | 320 | break; |
0cf43f50 | 321 | if (pos < 9 || pos == dst_len) |
3d5b1ecd | 322 | goto done; |
3d5b1ecd AZ |
323 | pos++; |
324 | ||
0cf43f50 HX |
325 | err = 0; |
326 | ||
327 | if (req->dst_len < dst_len - pos) | |
3d5b1ecd | 328 | err = -EOVERFLOW; |
0cf43f50 | 329 | req->dst_len = dst_len - pos; |
3d5b1ecd AZ |
330 | |
331 | if (!err) | |
332 | sg_copy_from_buffer(req->dst, | |
333 | sg_nents_for_len(req->dst, req->dst_len), | |
0cf43f50 | 334 | out_buf + pos, req->dst_len); |
3d5b1ecd AZ |
335 | |
336 | done: | |
337 | kzfree(req_ctx->out_buf); | |
338 | ||
339 | return err; | |
340 | } | |
341 | ||
342 | static 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 | ||
357 | static 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 | ||
3a32ce50 | 367 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
3d5b1ecd AZ |
368 | if (!req_ctx->out_buf) |
369 | return -ENOMEM; | |
370 | ||
371 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, | |
6f0904ad | 372 | ctx->key_size, NULL); |
3d5b1ecd AZ |
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 | ||
d858b071 HX |
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 | ||
3d5b1ecd | 383 | err = crypto_akcipher_decrypt(&req_ctx->child_req); |
4e5b0ad5 | 384 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
385 | return pkcs1pad_decrypt_complete(req, err); |
386 | ||
387 | return err; | |
388 | } | |
389 | ||
390 | static 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); | |
c0d20d22 HX |
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; | |
3d5b1ecd | 398 | int err; |
a49de377 | 399 | unsigned int ps_end, digest_size = 0; |
3d5b1ecd AZ |
400 | |
401 | if (!ctx->key_size) | |
402 | return -EINVAL; | |
403 | ||
c0d20d22 | 404 | digest_size = digest_info->size; |
a49de377 TS |
405 | |
406 | if (req->src_len + digest_size > ctx->key_size - 11) | |
3d5b1ecd AZ |
407 | return -EOVERFLOW; |
408 | ||
409 | if (req->dst_len < ctx->key_size) { | |
410 | req->dst_len = ctx->key_size; | |
411 | return -EOVERFLOW; | |
412 | } | |
413 | ||
3d5b1ecd | 414 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
3a32ce50 | 415 | GFP_KERNEL); |
3d5b1ecd AZ |
416 | if (!req_ctx->in_buf) |
417 | return -ENOMEM; | |
418 | ||
a49de377 | 419 | ps_end = ctx->key_size - digest_size - req->src_len - 2; |
3d5b1ecd AZ |
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 | ||
c0d20d22 HX |
424 | memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data, |
425 | digest_info->size); | |
a49de377 | 426 | |
3d5b1ecd AZ |
427 | pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf, |
428 | ctx->key_size - 1 - req->src_len, req->src); | |
429 | ||
3d5b1ecd AZ |
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 | ||
d858b071 HX |
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 | ||
3d5b1ecd | 438 | err = crypto_akcipher_sign(&req_ctx->child_req); |
4e5b0ad5 | 439 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
440 | return pkcs1pad_encrypt_sign_complete(req, err); |
441 | ||
442 | return err; | |
443 | } | |
444 | ||
445 | static 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); | |
c0d20d22 HX |
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; | |
27710b8e | 453 | unsigned int dst_len; |
3d5b1ecd | 454 | unsigned int pos; |
27710b8e | 455 | u8 *out_buf; |
3d5b1ecd AZ |
456 | |
457 | if (err) | |
458 | goto done; | |
459 | ||
27710b8e HX |
460 | err = -EINVAL; |
461 | dst_len = req_ctx->child_req.dst_len; | |
462 | if (dst_len < ctx->key_size - 1) | |
3d5b1ecd | 463 | goto done; |
27710b8e HX |
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++; | |
3d5b1ecd AZ |
473 | } |
474 | ||
a49de377 | 475 | err = -EBADMSG; |
27710b8e | 476 | if (out_buf[0] != 0x01) |
3d5b1ecd | 477 | goto done; |
a49de377 | 478 | |
27710b8e HX |
479 | for (pos = 1; pos < dst_len; pos++) |
480 | if (out_buf[pos] != 0xff) | |
3d5b1ecd | 481 | break; |
a49de377 | 482 | |
27710b8e | 483 | if (pos < 9 || pos == dst_len || out_buf[pos] != 0x00) |
3d5b1ecd | 484 | goto done; |
3d5b1ecd AZ |
485 | pos++; |
486 | ||
fec17cb2 | 487 | if (crypto_memneq(out_buf + pos, digest_info->data, digest_info->size)) |
c0d20d22 | 488 | goto done; |
a49de377 | 489 | |
c0d20d22 | 490 | pos += digest_info->size; |
a49de377 TS |
491 | |
492 | err = 0; | |
493 | ||
27710b8e | 494 | if (req->dst_len < dst_len - pos) |
3d5b1ecd | 495 | err = -EOVERFLOW; |
27710b8e | 496 | req->dst_len = dst_len - pos; |
3d5b1ecd AZ |
497 | |
498 | if (!err) | |
499 | sg_copy_from_buffer(req->dst, | |
500 | sg_nents_for_len(req->dst, req->dst_len), | |
27710b8e | 501 | out_buf + pos, req->dst_len); |
3d5b1ecd AZ |
502 | done: |
503 | kzfree(req_ctx->out_buf); | |
504 | ||
505 | return err; | |
506 | } | |
507 | ||
508 | static 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 | */ | |
531 | static 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 | ||
a49de377 | 538 | if (!ctx->key_size || req->src_len < ctx->key_size) |
3d5b1ecd AZ |
539 | return -EINVAL; |
540 | ||
3a32ce50 | 541 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
3d5b1ecd AZ |
542 | if (!req_ctx->out_buf) |
543 | return -ENOMEM; | |
544 | ||
545 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, | |
6f0904ad | 546 | ctx->key_size, NULL); |
3d5b1ecd AZ |
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 | ||
d858b071 HX |
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 | ||
3d5b1ecd | 557 | err = crypto_akcipher_verify(&req_ctx->child_req); |
4e5b0ad5 | 558 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
559 | return pkcs1pad_verify_complete(req, err); |
560 | ||
561 | return err; | |
562 | } | |
563 | ||
564 | static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm) | |
565 | { | |
566 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); | |
a49de377 | 567 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); |
3d5b1ecd AZ |
568 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
569 | struct crypto_akcipher *child_tfm; | |
570 | ||
c0d20d22 | 571 | child_tfm = crypto_spawn_akcipher(&ictx->spawn); |
3d5b1ecd AZ |
572 | if (IS_ERR(child_tfm)) |
573 | return PTR_ERR(child_tfm); | |
574 | ||
575 | ctx->child = child_tfm; | |
3d5b1ecd AZ |
576 | return 0; |
577 | } | |
578 | ||
579 | static 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 | ||
586 | static void pkcs1pad_free(struct akcipher_instance *inst) | |
587 | { | |
a49de377 TS |
588 | struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst); |
589 | struct crypto_akcipher_spawn *spawn = &ctx->spawn; | |
3d5b1ecd AZ |
590 | |
591 | crypto_drop_akcipher(spawn); | |
3d5b1ecd AZ |
592 | kfree(inst); |
593 | } | |
594 | ||
595 | static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb) | |
596 | { | |
c0d20d22 | 597 | const struct rsa_asn1_template *digest_info; |
3d5b1ecd AZ |
598 | struct crypto_attr_type *algt; |
599 | struct akcipher_instance *inst; | |
a49de377 | 600 | struct pkcs1pad_inst_ctx *ctx; |
3d5b1ecd AZ |
601 | struct crypto_akcipher_spawn *spawn; |
602 | struct akcipher_alg *rsa_alg; | |
603 | const char *rsa_alg_name; | |
a49de377 | 604 | const char *hash_name; |
3d5b1ecd AZ |
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 | ||
a49de377 TS |
618 | hash_name = crypto_attr_alg_name(tb[2]); |
619 | if (IS_ERR(hash_name)) | |
c0d20d22 HX |
620 | return PTR_ERR(hash_name); |
621 | ||
622 | digest_info = rsa_lookup_asn1(hash_name); | |
623 | if (!digest_info) | |
624 | return -EINVAL; | |
a49de377 TS |
625 | |
626 | inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); | |
3d5b1ecd AZ |
627 | if (!inst) |
628 | return -ENOMEM; | |
629 | ||
a49de377 TS |
630 | ctx = akcipher_instance_ctx(inst); |
631 | spawn = &ctx->spawn; | |
c0d20d22 | 632 | ctx->digest_info = digest_info; |
a49de377 | 633 | |
3d5b1ecd AZ |
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; | |
a49de377 | 643 | |
c0d20d22 HX |
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) | |
3d5b1ecd AZ |
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) | |
c0d20d22 | 673 | goto out_drop_alg; |
3d5b1ecd AZ |
674 | |
675 | return 0; | |
676 | ||
677 | out_drop_alg: | |
678 | crypto_drop_akcipher(spawn); | |
679 | out_free_inst: | |
680 | kfree(inst); | |
681 | return err; | |
682 | } | |
683 | ||
684 | struct crypto_template rsa_pkcs1pad_tmpl = { | |
685 | .name = "pkcs1pad", | |
686 | .create = pkcs1pad_create, | |
687 | .module = THIS_MODULE, | |
688 | }; |