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Commit | Line | Data |
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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
3d5b1ecd AZ |
2 | /* |
3 | * RSA padding templates. | |
4 | * | |
5 | * Copyright (c) 2015 Intel Corporation | |
3d5b1ecd AZ |
6 | */ |
7 | ||
8 | #include <crypto/algapi.h> | |
9 | #include <crypto/akcipher.h> | |
10 | #include <crypto/internal/akcipher.h> | |
a1180cff | 11 | #include <crypto/internal/rsa.h> |
3d5b1ecd AZ |
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> | |
0c3dc787 | 17 | #include <linux/scatterlist.h> |
3d5b1ecd | 18 | |
a49de377 TS |
19 | /* |
20 | * Hash algorithm OIDs plus ASN.1 DER wrappings [RFC4880 sec 5.2.2]. | |
21 | */ | |
22 | static 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 | ||
28 | static 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 | ||
34 | static 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 | ||
40 | static 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 | ||
46 | static 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 | ||
52 | static 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 | ||
58 | static 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 | ||
64 | static const struct rsa_asn1_template { | |
65 | const char *name; | |
66 | const u8 *data; | |
67 | size_t size; | |
68 | } rsa_asn1_templates[] = { | |
69 | #define _(X) { #X, rsa_digest_info_##X, sizeof(rsa_digest_info_##X) } | |
70 | _(md5), | |
71 | _(sha1), | |
72 | _(rmd160), | |
73 | _(sha256), | |
74 | _(sha384), | |
75 | _(sha512), | |
76 | _(sha224), | |
77 | { NULL } | |
78 | #undef _ | |
79 | }; | |
80 | ||
81 | static const struct rsa_asn1_template *rsa_lookup_asn1(const char *name) | |
82 | { | |
83 | const struct rsa_asn1_template *p; | |
84 | ||
85 | for (p = rsa_asn1_templates; p->name; p++) | |
86 | if (strcmp(name, p->name) == 0) | |
87 | return p; | |
88 | return NULL; | |
89 | } | |
90 | ||
3d5b1ecd AZ |
91 | struct pkcs1pad_ctx { |
92 | struct crypto_akcipher *child; | |
3d5b1ecd AZ |
93 | unsigned int key_size; |
94 | }; | |
95 | ||
a49de377 TS |
96 | struct pkcs1pad_inst_ctx { |
97 | struct crypto_akcipher_spawn spawn; | |
c0d20d22 | 98 | const struct rsa_asn1_template *digest_info; |
a49de377 TS |
99 | }; |
100 | ||
3d5b1ecd | 101 | struct pkcs1pad_request { |
0f2c8319 | 102 | struct scatterlist in_sg[2], out_sg[1]; |
3d5b1ecd | 103 | uint8_t *in_buf, *out_buf; |
a6d7bfd0 | 104 | struct akcipher_request child_req; |
3d5b1ecd AZ |
105 | }; |
106 | ||
107 | static int pkcs1pad_set_pub_key(struct crypto_akcipher *tfm, const void *key, | |
108 | unsigned int keylen) | |
109 | { | |
110 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
73f79189 HX |
111 | int err; |
112 | ||
113 | ctx->key_size = 0; | |
3d5b1ecd AZ |
114 | |
115 | err = crypto_akcipher_set_pub_key(ctx->child, key, keylen); | |
73f79189 HX |
116 | if (err) |
117 | return err; | |
3d5b1ecd | 118 | |
73f79189 HX |
119 | /* Find out new modulus size from rsa implementation */ |
120 | err = crypto_akcipher_maxsize(ctx->child); | |
73f79189 HX |
121 | if (err > PAGE_SIZE) |
122 | return -ENOTSUPP; | |
3d5b1ecd | 123 | |
73f79189 HX |
124 | ctx->key_size = err; |
125 | return 0; | |
3d5b1ecd AZ |
126 | } |
127 | ||
128 | static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key, | |
129 | unsigned int keylen) | |
130 | { | |
131 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
73f79189 HX |
132 | int err; |
133 | ||
134 | ctx->key_size = 0; | |
3d5b1ecd AZ |
135 | |
136 | err = crypto_akcipher_set_priv_key(ctx->child, key, keylen); | |
73f79189 HX |
137 | if (err) |
138 | return err; | |
3d5b1ecd | 139 | |
73f79189 HX |
140 | /* Find out new modulus size from rsa implementation */ |
141 | err = crypto_akcipher_maxsize(ctx->child); | |
73f79189 HX |
142 | if (err > PAGE_SIZE) |
143 | return -ENOTSUPP; | |
3d5b1ecd | 144 | |
73f79189 HX |
145 | ctx->key_size = err; |
146 | return 0; | |
3d5b1ecd AZ |
147 | } |
148 | ||
543de102 | 149 | static unsigned int pkcs1pad_get_max_size(struct crypto_akcipher *tfm) |
3d5b1ecd AZ |
150 | { |
151 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
152 | ||
153 | /* | |
154 | * The maximum destination buffer size for the encrypt/sign operations | |
155 | * will be the same as for RSA, even though it's smaller for | |
156 | * decrypt/verify. | |
157 | */ | |
158 | ||
543de102 | 159 | return ctx->key_size; |
3d5b1ecd AZ |
160 | } |
161 | ||
162 | static void pkcs1pad_sg_set_buf(struct scatterlist *sg, void *buf, size_t len, | |
163 | struct scatterlist *next) | |
164 | { | |
0f2c8319 HX |
165 | int nsegs = next ? 2 : 1; |
166 | ||
167 | sg_init_table(sg, nsegs); | |
168 | sg_set_buf(sg, buf, len); | |
3d5b1ecd AZ |
169 | |
170 | if (next) | |
171 | sg_chain(sg, nsegs, next); | |
172 | } | |
173 | ||
174 | static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err) | |
175 | { | |
176 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
177 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
178 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
d858b071 HX |
179 | unsigned int pad_len; |
180 | unsigned int len; | |
181 | u8 *out_buf; | |
182 | ||
183 | if (err) | |
184 | goto out; | |
185 | ||
186 | len = req_ctx->child_req.dst_len; | |
187 | pad_len = ctx->key_size - len; | |
188 | ||
189 | /* Four billion to one */ | |
190 | if (likely(!pad_len)) | |
191 | goto out; | |
192 | ||
1ca28098 | 193 | out_buf = kzalloc(ctx->key_size, GFP_KERNEL); |
d858b071 HX |
194 | err = -ENOMEM; |
195 | if (!out_buf) | |
196 | goto out; | |
197 | ||
198 | sg_copy_to_buffer(req->dst, sg_nents_for_len(req->dst, len), | |
199 | out_buf + pad_len, len); | |
200 | sg_copy_from_buffer(req->dst, | |
201 | sg_nents_for_len(req->dst, ctx->key_size), | |
202 | out_buf, ctx->key_size); | |
453431a5 | 203 | kfree_sensitive(out_buf); |
d858b071 HX |
204 | |
205 | out: | |
3d5b1ecd AZ |
206 | req->dst_len = ctx->key_size; |
207 | ||
208 | kfree(req_ctx->in_buf); | |
3d5b1ecd AZ |
209 | |
210 | return err; | |
211 | } | |
212 | ||
213 | static void pkcs1pad_encrypt_sign_complete_cb( | |
214 | struct crypto_async_request *child_async_req, int err) | |
215 | { | |
216 | struct akcipher_request *req = child_async_req->data; | |
217 | struct crypto_async_request async_req; | |
218 | ||
219 | if (err == -EINPROGRESS) | |
220 | return; | |
221 | ||
222 | async_req.data = req->base.data; | |
223 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); | |
224 | async_req.flags = child_async_req->flags; | |
225 | req->base.complete(&async_req, | |
226 | pkcs1pad_encrypt_sign_complete(req, err)); | |
227 | } | |
228 | ||
229 | static int pkcs1pad_encrypt(struct akcipher_request *req) | |
230 | { | |
231 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
232 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
233 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
234 | int err; | |
235 | unsigned int i, ps_end; | |
236 | ||
237 | if (!ctx->key_size) | |
238 | return -EINVAL; | |
239 | ||
240 | if (req->src_len > ctx->key_size - 11) | |
241 | return -EOVERFLOW; | |
242 | ||
243 | if (req->dst_len < ctx->key_size) { | |
244 | req->dst_len = ctx->key_size; | |
245 | return -EOVERFLOW; | |
246 | } | |
247 | ||
3d5b1ecd | 248 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
3a32ce50 | 249 | GFP_KERNEL); |
3d5b1ecd AZ |
250 | if (!req_ctx->in_buf) |
251 | return -ENOMEM; | |
252 | ||
253 | ps_end = ctx->key_size - req->src_len - 2; | |
254 | req_ctx->in_buf[0] = 0x02; | |
255 | for (i = 1; i < ps_end; i++) | |
256 | req_ctx->in_buf[i] = 1 + prandom_u32_max(255); | |
257 | req_ctx->in_buf[ps_end] = 0x00; | |
258 | ||
259 | pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf, | |
260 | ctx->key_size - 1 - req->src_len, req->src); | |
261 | ||
3d5b1ecd AZ |
262 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
263 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, | |
264 | pkcs1pad_encrypt_sign_complete_cb, req); | |
265 | ||
d858b071 HX |
266 | /* Reuse output buffer */ |
267 | akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg, | |
268 | req->dst, ctx->key_size - 1, req->dst_len); | |
269 | ||
3d5b1ecd | 270 | err = crypto_akcipher_encrypt(&req_ctx->child_req); |
4e5b0ad5 | 271 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
272 | return pkcs1pad_encrypt_sign_complete(req, err); |
273 | ||
274 | return err; | |
275 | } | |
276 | ||
277 | static int pkcs1pad_decrypt_complete(struct akcipher_request *req, int err) | |
278 | { | |
279 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
280 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
281 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
0cf43f50 | 282 | unsigned int dst_len; |
3d5b1ecd | 283 | unsigned int pos; |
0cf43f50 | 284 | u8 *out_buf; |
3d5b1ecd AZ |
285 | |
286 | if (err) | |
287 | goto done; | |
288 | ||
0cf43f50 HX |
289 | err = -EINVAL; |
290 | dst_len = req_ctx->child_req.dst_len; | |
291 | if (dst_len < ctx->key_size - 1) | |
3d5b1ecd | 292 | goto done; |
0cf43f50 HX |
293 | |
294 | out_buf = req_ctx->out_buf; | |
295 | if (dst_len == ctx->key_size) { | |
296 | if (out_buf[0] != 0x00) | |
297 | /* Decrypted value had no leading 0 byte */ | |
298 | goto done; | |
299 | ||
300 | dst_len--; | |
301 | out_buf++; | |
3d5b1ecd AZ |
302 | } |
303 | ||
0cf43f50 | 304 | if (out_buf[0] != 0x02) |
3d5b1ecd | 305 | goto done; |
0cf43f50 HX |
306 | |
307 | for (pos = 1; pos < dst_len; pos++) | |
308 | if (out_buf[pos] == 0x00) | |
3d5b1ecd | 309 | break; |
0cf43f50 | 310 | if (pos < 9 || pos == dst_len) |
3d5b1ecd | 311 | goto done; |
3d5b1ecd AZ |
312 | pos++; |
313 | ||
0cf43f50 HX |
314 | err = 0; |
315 | ||
316 | if (req->dst_len < dst_len - pos) | |
3d5b1ecd | 317 | err = -EOVERFLOW; |
0cf43f50 | 318 | req->dst_len = dst_len - pos; |
3d5b1ecd AZ |
319 | |
320 | if (!err) | |
321 | sg_copy_from_buffer(req->dst, | |
322 | sg_nents_for_len(req->dst, req->dst_len), | |
0cf43f50 | 323 | out_buf + pos, req->dst_len); |
3d5b1ecd AZ |
324 | |
325 | done: | |
453431a5 | 326 | kfree_sensitive(req_ctx->out_buf); |
3d5b1ecd AZ |
327 | |
328 | return err; | |
329 | } | |
330 | ||
331 | static void pkcs1pad_decrypt_complete_cb( | |
332 | struct crypto_async_request *child_async_req, int err) | |
333 | { | |
334 | struct akcipher_request *req = child_async_req->data; | |
335 | struct crypto_async_request async_req; | |
336 | ||
337 | if (err == -EINPROGRESS) | |
338 | return; | |
339 | ||
340 | async_req.data = req->base.data; | |
341 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); | |
342 | async_req.flags = child_async_req->flags; | |
343 | req->base.complete(&async_req, pkcs1pad_decrypt_complete(req, err)); | |
344 | } | |
345 | ||
346 | static int pkcs1pad_decrypt(struct akcipher_request *req) | |
347 | { | |
348 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
349 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
350 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
351 | int err; | |
352 | ||
353 | if (!ctx->key_size || req->src_len != ctx->key_size) | |
354 | return -EINVAL; | |
355 | ||
3a32ce50 | 356 | req_ctx->out_buf = kmalloc(ctx->key_size, GFP_KERNEL); |
3d5b1ecd AZ |
357 | if (!req_ctx->out_buf) |
358 | return -ENOMEM; | |
359 | ||
360 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, | |
6f0904ad | 361 | ctx->key_size, NULL); |
3d5b1ecd AZ |
362 | |
363 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); | |
364 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, | |
365 | pkcs1pad_decrypt_complete_cb, req); | |
366 | ||
d858b071 HX |
367 | /* Reuse input buffer, output to a new buffer */ |
368 | akcipher_request_set_crypt(&req_ctx->child_req, req->src, | |
369 | req_ctx->out_sg, req->src_len, | |
370 | ctx->key_size); | |
371 | ||
3d5b1ecd | 372 | err = crypto_akcipher_decrypt(&req_ctx->child_req); |
4e5b0ad5 | 373 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
374 | return pkcs1pad_decrypt_complete(req, err); |
375 | ||
376 | return err; | |
377 | } | |
378 | ||
379 | static int pkcs1pad_sign(struct akcipher_request *req) | |
380 | { | |
381 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
382 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
383 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
c0d20d22 HX |
384 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); |
385 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); | |
386 | const struct rsa_asn1_template *digest_info = ictx->digest_info; | |
3d5b1ecd | 387 | int err; |
c2a28fdb | 388 | unsigned int ps_end, digest_info_size = 0; |
3d5b1ecd AZ |
389 | |
390 | if (!ctx->key_size) | |
391 | return -EINVAL; | |
392 | ||
b3a8c8a5 | 393 | if (digest_info) |
c2a28fdb | 394 | digest_info_size = digest_info->size; |
a49de377 | 395 | |
c2a28fdb | 396 | if (req->src_len + digest_info_size > ctx->key_size - 11) |
3d5b1ecd AZ |
397 | return -EOVERFLOW; |
398 | ||
399 | if (req->dst_len < ctx->key_size) { | |
400 | req->dst_len = ctx->key_size; | |
401 | return -EOVERFLOW; | |
402 | } | |
403 | ||
3d5b1ecd | 404 | req_ctx->in_buf = kmalloc(ctx->key_size - 1 - req->src_len, |
3a32ce50 | 405 | GFP_KERNEL); |
3d5b1ecd AZ |
406 | if (!req_ctx->in_buf) |
407 | return -ENOMEM; | |
408 | ||
c2a28fdb | 409 | ps_end = ctx->key_size - digest_info_size - req->src_len - 2; |
3d5b1ecd AZ |
410 | req_ctx->in_buf[0] = 0x01; |
411 | memset(req_ctx->in_buf + 1, 0xff, ps_end - 1); | |
412 | req_ctx->in_buf[ps_end] = 0x00; | |
413 | ||
b3a8c8a5 DK |
414 | if (digest_info) |
415 | memcpy(req_ctx->in_buf + ps_end + 1, digest_info->data, | |
416 | digest_info->size); | |
a49de377 | 417 | |
3d5b1ecd AZ |
418 | pkcs1pad_sg_set_buf(req_ctx->in_sg, req_ctx->in_buf, |
419 | ctx->key_size - 1 - req->src_len, req->src); | |
420 | ||
3d5b1ecd AZ |
421 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); |
422 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, | |
423 | pkcs1pad_encrypt_sign_complete_cb, req); | |
424 | ||
d858b071 HX |
425 | /* Reuse output buffer */ |
426 | akcipher_request_set_crypt(&req_ctx->child_req, req_ctx->in_sg, | |
427 | req->dst, ctx->key_size - 1, req->dst_len); | |
428 | ||
3ecc9725 | 429 | err = crypto_akcipher_decrypt(&req_ctx->child_req); |
4e5b0ad5 | 430 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
431 | return pkcs1pad_encrypt_sign_complete(req, err); |
432 | ||
433 | return err; | |
434 | } | |
435 | ||
436 | static int pkcs1pad_verify_complete(struct akcipher_request *req, int err) | |
437 | { | |
438 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
439 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
440 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
c0d20d22 HX |
441 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); |
442 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); | |
443 | const struct rsa_asn1_template *digest_info = ictx->digest_info; | |
c2a28fdb EB |
444 | const unsigned int sig_size = req->src_len; |
445 | const unsigned int digest_size = req->dst_len; | |
27710b8e | 446 | unsigned int dst_len; |
3d5b1ecd | 447 | unsigned int pos; |
27710b8e | 448 | u8 *out_buf; |
3d5b1ecd AZ |
449 | |
450 | if (err) | |
451 | goto done; | |
452 | ||
27710b8e HX |
453 | err = -EINVAL; |
454 | dst_len = req_ctx->child_req.dst_len; | |
455 | if (dst_len < ctx->key_size - 1) | |
3d5b1ecd | 456 | goto done; |
27710b8e HX |
457 | |
458 | out_buf = req_ctx->out_buf; | |
459 | if (dst_len == ctx->key_size) { | |
460 | if (out_buf[0] != 0x00) | |
461 | /* Decrypted value had no leading 0 byte */ | |
462 | goto done; | |
463 | ||
464 | dst_len--; | |
465 | out_buf++; | |
3d5b1ecd AZ |
466 | } |
467 | ||
a49de377 | 468 | err = -EBADMSG; |
27710b8e | 469 | if (out_buf[0] != 0x01) |
3d5b1ecd | 470 | goto done; |
a49de377 | 471 | |
27710b8e HX |
472 | for (pos = 1; pos < dst_len; pos++) |
473 | if (out_buf[pos] != 0xff) | |
3d5b1ecd | 474 | break; |
a49de377 | 475 | |
27710b8e | 476 | if (pos < 9 || pos == dst_len || out_buf[pos] != 0x00) |
3d5b1ecd | 477 | goto done; |
3d5b1ecd AZ |
478 | pos++; |
479 | ||
b3a8c8a5 | 480 | if (digest_info) { |
a24611ea EB |
481 | if (digest_info->size > dst_len - pos) |
482 | goto done; | |
b3a8c8a5 DK |
483 | if (crypto_memneq(out_buf + pos, digest_info->data, |
484 | digest_info->size)) | |
485 | goto done; | |
a49de377 | 486 | |
b3a8c8a5 DK |
487 | pos += digest_info->size; |
488 | } | |
a49de377 TS |
489 | |
490 | err = 0; | |
491 | ||
c2a28fdb | 492 | if (digest_size != dst_len - pos) { |
c7381b01 VC |
493 | err = -EKEYREJECTED; |
494 | req->dst_len = dst_len - pos; | |
495 | goto done; | |
496 | } | |
497 | /* Extract appended digest. */ | |
498 | sg_pcopy_to_buffer(req->src, | |
c2a28fdb | 499 | sg_nents_for_len(req->src, sig_size + digest_size), |
c7381b01 | 500 | req_ctx->out_buf + ctx->key_size, |
c2a28fdb | 501 | digest_size, sig_size); |
c7381b01 VC |
502 | /* Do the actual verification step. */ |
503 | if (memcmp(req_ctx->out_buf + ctx->key_size, out_buf + pos, | |
c2a28fdb | 504 | digest_size) != 0) |
c7381b01 | 505 | err = -EKEYREJECTED; |
3d5b1ecd | 506 | done: |
453431a5 | 507 | kfree_sensitive(req_ctx->out_buf); |
3d5b1ecd AZ |
508 | |
509 | return err; | |
510 | } | |
511 | ||
512 | static void pkcs1pad_verify_complete_cb( | |
513 | struct crypto_async_request *child_async_req, int err) | |
514 | { | |
515 | struct akcipher_request *req = child_async_req->data; | |
516 | struct crypto_async_request async_req; | |
517 | ||
518 | if (err == -EINPROGRESS) | |
519 | return; | |
520 | ||
521 | async_req.data = req->base.data; | |
522 | async_req.tfm = crypto_akcipher_tfm(crypto_akcipher_reqtfm(req)); | |
523 | async_req.flags = child_async_req->flags; | |
524 | req->base.complete(&async_req, pkcs1pad_verify_complete(req, err)); | |
525 | } | |
526 | ||
527 | /* | |
528 | * The verify operation is here for completeness similar to the verification | |
529 | * defined in RFC2313 section 10.2 except that block type 0 is not accepted, | |
530 | * as in RFC2437. RFC2437 section 9.2 doesn't define any operation to | |
531 | * retrieve the DigestInfo from a signature, instead the user is expected | |
532 | * to call the sign operation to generate the expected signature and compare | |
533 | * signatures instead of the message-digests. | |
534 | */ | |
535 | static int pkcs1pad_verify(struct akcipher_request *req) | |
536 | { | |
537 | struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); | |
538 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
539 | struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); | |
c2a28fdb EB |
540 | const unsigned int sig_size = req->src_len; |
541 | const unsigned int digest_size = req->dst_len; | |
3d5b1ecd AZ |
542 | int err; |
543 | ||
c2a28fdb EB |
544 | if (WARN_ON(req->dst) || WARN_ON(!digest_size) || |
545 | !ctx->key_size || sig_size != ctx->key_size) | |
3d5b1ecd AZ |
546 | return -EINVAL; |
547 | ||
c2a28fdb | 548 | req_ctx->out_buf = kmalloc(ctx->key_size + digest_size, GFP_KERNEL); |
3d5b1ecd AZ |
549 | if (!req_ctx->out_buf) |
550 | return -ENOMEM; | |
551 | ||
552 | pkcs1pad_sg_set_buf(req_ctx->out_sg, req_ctx->out_buf, | |
6f0904ad | 553 | ctx->key_size, NULL); |
3d5b1ecd AZ |
554 | |
555 | akcipher_request_set_tfm(&req_ctx->child_req, ctx->child); | |
556 | akcipher_request_set_callback(&req_ctx->child_req, req->base.flags, | |
557 | pkcs1pad_verify_complete_cb, req); | |
558 | ||
d858b071 HX |
559 | /* Reuse input buffer, output to a new buffer */ |
560 | akcipher_request_set_crypt(&req_ctx->child_req, req->src, | |
c2a28fdb | 561 | req_ctx->out_sg, sig_size, ctx->key_size); |
d858b071 | 562 | |
3ecc9725 | 563 | err = crypto_akcipher_encrypt(&req_ctx->child_req); |
4e5b0ad5 | 564 | if (err != -EINPROGRESS && err != -EBUSY) |
3d5b1ecd AZ |
565 | return pkcs1pad_verify_complete(req, err); |
566 | ||
567 | return err; | |
568 | } | |
569 | ||
570 | static int pkcs1pad_init_tfm(struct crypto_akcipher *tfm) | |
571 | { | |
572 | struct akcipher_instance *inst = akcipher_alg_instance(tfm); | |
a49de377 | 573 | struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst); |
3d5b1ecd AZ |
574 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); |
575 | struct crypto_akcipher *child_tfm; | |
576 | ||
c0d20d22 | 577 | child_tfm = crypto_spawn_akcipher(&ictx->spawn); |
3d5b1ecd AZ |
578 | if (IS_ERR(child_tfm)) |
579 | return PTR_ERR(child_tfm); | |
580 | ||
581 | ctx->child = child_tfm; | |
3d5b1ecd AZ |
582 | return 0; |
583 | } | |
584 | ||
585 | static void pkcs1pad_exit_tfm(struct crypto_akcipher *tfm) | |
586 | { | |
587 | struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); | |
588 | ||
589 | crypto_free_akcipher(ctx->child); | |
590 | } | |
591 | ||
592 | static void pkcs1pad_free(struct akcipher_instance *inst) | |
593 | { | |
a49de377 TS |
594 | struct pkcs1pad_inst_ctx *ctx = akcipher_instance_ctx(inst); |
595 | struct crypto_akcipher_spawn *spawn = &ctx->spawn; | |
3d5b1ecd AZ |
596 | |
597 | crypto_drop_akcipher(spawn); | |
3d5b1ecd AZ |
598 | kfree(inst); |
599 | } | |
600 | ||
601 | static int pkcs1pad_create(struct crypto_template *tmpl, struct rtattr **tb) | |
602 | { | |
73bed26f | 603 | u32 mask; |
3d5b1ecd | 604 | struct akcipher_instance *inst; |
a49de377 | 605 | struct pkcs1pad_inst_ctx *ctx; |
3d5b1ecd | 606 | struct akcipher_alg *rsa_alg; |
a49de377 | 607 | const char *hash_name; |
3d5b1ecd AZ |
608 | int err; |
609 | ||
7bcb2c99 EB |
610 | err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AKCIPHER, &mask); |
611 | if (err) | |
612 | return err; | |
73bed26f | 613 | |
a49de377 | 614 | inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); |
3d5b1ecd AZ |
615 | if (!inst) |
616 | return -ENOMEM; | |
617 | ||
a49de377 | 618 | ctx = akcipher_instance_ctx(inst); |
a49de377 | 619 | |
0708bb43 EB |
620 | err = crypto_grab_akcipher(&ctx->spawn, akcipher_crypto_instance(inst), |
621 | crypto_attr_alg_name(tb[1]), 0, mask); | |
3d5b1ecd | 622 | if (err) |
0708bb43 | 623 | goto err_free_inst; |
3d5b1ecd | 624 | |
0708bb43 | 625 | rsa_alg = crypto_spawn_akcipher_alg(&ctx->spawn); |
3d5b1ecd | 626 | |
9b30430e EB |
627 | if (strcmp(rsa_alg->base.cra_name, "rsa") != 0) { |
628 | err = -EINVAL; | |
629 | goto err_free_inst; | |
630 | } | |
631 | ||
3d5b1ecd | 632 | err = -ENAMETOOLONG; |
0708bb43 EB |
633 | hash_name = crypto_attr_alg_name(tb[2]); |
634 | if (IS_ERR(hash_name)) { | |
b3a8c8a5 DK |
635 | if (snprintf(inst->alg.base.cra_name, |
636 | CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)", | |
637 | rsa_alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME) | |
0708bb43 | 638 | goto err_free_inst; |
b3a8c8a5 DK |
639 | |
640 | if (snprintf(inst->alg.base.cra_driver_name, | |
641 | CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s)", | |
642 | rsa_alg->base.cra_driver_name) >= | |
643 | CRYPTO_MAX_ALG_NAME) | |
0708bb43 | 644 | goto err_free_inst; |
b3a8c8a5 | 645 | } else { |
0708bb43 EB |
646 | ctx->digest_info = rsa_lookup_asn1(hash_name); |
647 | if (!ctx->digest_info) { | |
648 | err = -EINVAL; | |
649 | goto err_free_inst; | |
650 | } | |
651 | ||
b3a8c8a5 DK |
652 | if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, |
653 | "pkcs1pad(%s,%s)", rsa_alg->base.cra_name, | |
654 | hash_name) >= CRYPTO_MAX_ALG_NAME) | |
0708bb43 | 655 | goto err_free_inst; |
b3a8c8a5 DK |
656 | |
657 | if (snprintf(inst->alg.base.cra_driver_name, | |
658 | CRYPTO_MAX_ALG_NAME, "pkcs1pad(%s,%s)", | |
659 | rsa_alg->base.cra_driver_name, | |
660 | hash_name) >= CRYPTO_MAX_ALG_NAME) | |
0708bb43 | 661 | goto err_free_inst; |
b3a8c8a5 | 662 | } |
3d5b1ecd | 663 | |
3d5b1ecd AZ |
664 | inst->alg.base.cra_priority = rsa_alg->base.cra_priority; |
665 | inst->alg.base.cra_ctxsize = sizeof(struct pkcs1pad_ctx); | |
666 | ||
667 | inst->alg.init = pkcs1pad_init_tfm; | |
668 | inst->alg.exit = pkcs1pad_exit_tfm; | |
669 | ||
670 | inst->alg.encrypt = pkcs1pad_encrypt; | |
671 | inst->alg.decrypt = pkcs1pad_decrypt; | |
672 | inst->alg.sign = pkcs1pad_sign; | |
673 | inst->alg.verify = pkcs1pad_verify; | |
674 | inst->alg.set_pub_key = pkcs1pad_set_pub_key; | |
675 | inst->alg.set_priv_key = pkcs1pad_set_priv_key; | |
676 | inst->alg.max_size = pkcs1pad_get_max_size; | |
677 | inst->alg.reqsize = sizeof(struct pkcs1pad_request) + rsa_alg->reqsize; | |
678 | ||
679 | inst->free = pkcs1pad_free; | |
680 | ||
681 | err = akcipher_register_instance(tmpl, inst); | |
0708bb43 EB |
682 | if (err) { |
683 | err_free_inst: | |
684 | pkcs1pad_free(inst); | |
685 | } | |
3d5b1ecd AZ |
686 | return err; |
687 | } | |
688 | ||
689 | struct crypto_template rsa_pkcs1pad_tmpl = { | |
690 | .name = "pkcs1pad", | |
691 | .create = pkcs1pad_create, | |
692 | .module = THIS_MODULE, | |
693 | }; |