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Commit | Line | Data |
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3323eec9 MZ |
1 | /* |
2 | * Copyright (C) 2005,2006,2007,2008 IBM Corporation | |
3 | * | |
4 | * Authors: | |
5 | * Mimi Zohar <zohar@us.ibm.com> | |
6 | * Kylene Hall <kjhall@us.ibm.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation, version 2 of the License. | |
11 | * | |
12 | * File: ima_crypto.c | |
2bb930ab | 13 | * Calculates md5/sha1 file hash, template hash, boot-aggreate hash |
3323eec9 MZ |
14 | */ |
15 | ||
20ee451f JP |
16 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
17 | ||
3323eec9 | 18 | #include <linux/kernel.h> |
3bcced39 DK |
19 | #include <linux/moduleparam.h> |
20 | #include <linux/ratelimit.h> | |
3323eec9 MZ |
21 | #include <linux/file.h> |
22 | #include <linux/crypto.h> | |
23 | #include <linux/scatterlist.h> | |
24 | #include <linux/err.h> | |
5a0e3ad6 | 25 | #include <linux/slab.h> |
76bb28f6 | 26 | #include <crypto/hash.h> |
1525b06d | 27 | |
3323eec9 MZ |
28 | #include "ima.h" |
29 | ||
3bcced39 DK |
30 | /* minimum file size for ahash use */ |
31 | static unsigned long ima_ahash_minsize; | |
32 | module_param_named(ahash_minsize, ima_ahash_minsize, ulong, 0644); | |
33 | MODULE_PARM_DESC(ahash_minsize, "Minimum file size for ahash use"); | |
34 | ||
6edf7a89 DK |
35 | /* default is 0 - 1 page. */ |
36 | static int ima_maxorder; | |
37 | static unsigned int ima_bufsize = PAGE_SIZE; | |
38 | ||
39 | static int param_set_bufsize(const char *val, const struct kernel_param *kp) | |
40 | { | |
41 | unsigned long long size; | |
42 | int order; | |
43 | ||
44 | size = memparse(val, NULL); | |
45 | order = get_order(size); | |
46 | if (order >= MAX_ORDER) | |
47 | return -EINVAL; | |
48 | ima_maxorder = order; | |
49 | ima_bufsize = PAGE_SIZE << order; | |
50 | return 0; | |
51 | } | |
52 | ||
9c27847d | 53 | static const struct kernel_param_ops param_ops_bufsize = { |
6edf7a89 DK |
54 | .set = param_set_bufsize, |
55 | .get = param_get_uint, | |
56 | }; | |
57 | #define param_check_bufsize(name, p) __param_check(name, p, unsigned int) | |
58 | ||
59 | module_param_named(ahash_bufsize, ima_bufsize, bufsize, 0644); | |
60 | MODULE_PARM_DESC(ahash_bufsize, "Maximum ahash buffer size"); | |
61 | ||
76bb28f6 | 62 | static struct crypto_shash *ima_shash_tfm; |
3bcced39 | 63 | static struct crypto_ahash *ima_ahash_tfm; |
76bb28f6 | 64 | |
e4a9c519 | 65 | int __init ima_init_crypto(void) |
3323eec9 | 66 | { |
76bb28f6 | 67 | long rc; |
3323eec9 | 68 | |
c7c8bb23 | 69 | ima_shash_tfm = crypto_alloc_shash(hash_algo_name[ima_hash_algo], 0, 0); |
76bb28f6 DK |
70 | if (IS_ERR(ima_shash_tfm)) { |
71 | rc = PTR_ERR(ima_shash_tfm); | |
c7c8bb23 DK |
72 | pr_err("Can not allocate %s (reason: %ld)\n", |
73 | hash_algo_name[ima_hash_algo], rc); | |
3323eec9 MZ |
74 | return rc; |
75 | } | |
8a048adc PV |
76 | pr_info("Allocated hash algorithm: %s\n", |
77 | hash_algo_name[ima_hash_algo]); | |
76bb28f6 | 78 | return 0; |
3323eec9 MZ |
79 | } |
80 | ||
723326b9 DK |
81 | static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo) |
82 | { | |
83 | struct crypto_shash *tfm = ima_shash_tfm; | |
84 | int rc; | |
85 | ||
23c19e2c DK |
86 | if (algo < 0 || algo >= HASH_ALGO__LAST) |
87 | algo = ima_hash_algo; | |
88 | ||
89 | if (algo != ima_hash_algo) { | |
723326b9 DK |
90 | tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0); |
91 | if (IS_ERR(tfm)) { | |
92 | rc = PTR_ERR(tfm); | |
93 | pr_err("Can not allocate %s (reason: %d)\n", | |
94 | hash_algo_name[algo], rc); | |
95 | } | |
96 | } | |
97 | return tfm; | |
98 | } | |
99 | ||
100 | static void ima_free_tfm(struct crypto_shash *tfm) | |
101 | { | |
102 | if (tfm != ima_shash_tfm) | |
103 | crypto_free_shash(tfm); | |
104 | } | |
105 | ||
6edf7a89 DK |
106 | /** |
107 | * ima_alloc_pages() - Allocate contiguous pages. | |
108 | * @max_size: Maximum amount of memory to allocate. | |
109 | * @allocated_size: Returned size of actual allocation. | |
110 | * @last_warn: Should the min_size allocation warn or not. | |
111 | * | |
112 | * Tries to do opportunistic allocation for memory first trying to allocate | |
113 | * max_size amount of memory and then splitting that until zero order is | |
114 | * reached. Allocation is tried without generating allocation warnings unless | |
115 | * last_warn is set. Last_warn set affects only last allocation of zero order. | |
116 | * | |
117 | * By default, ima_maxorder is 0 and it is equivalent to kmalloc(GFP_KERNEL) | |
118 | * | |
119 | * Return pointer to allocated memory, or NULL on failure. | |
120 | */ | |
121 | static void *ima_alloc_pages(loff_t max_size, size_t *allocated_size, | |
122 | int last_warn) | |
123 | { | |
124 | void *ptr; | |
125 | int order = ima_maxorder; | |
71baba4b | 126 | gfp_t gfp_mask = __GFP_RECLAIM | __GFP_NOWARN | __GFP_NORETRY; |
6edf7a89 DK |
127 | |
128 | if (order) | |
129 | order = min(get_order(max_size), order); | |
130 | ||
131 | for (; order; order--) { | |
132 | ptr = (void *)__get_free_pages(gfp_mask, order); | |
133 | if (ptr) { | |
134 | *allocated_size = PAGE_SIZE << order; | |
135 | return ptr; | |
136 | } | |
137 | } | |
138 | ||
139 | /* order is zero - one page */ | |
140 | ||
141 | gfp_mask = GFP_KERNEL; | |
142 | ||
143 | if (!last_warn) | |
144 | gfp_mask |= __GFP_NOWARN; | |
145 | ||
146 | ptr = (void *)__get_free_pages(gfp_mask, 0); | |
147 | if (ptr) { | |
148 | *allocated_size = PAGE_SIZE; | |
149 | return ptr; | |
150 | } | |
151 | ||
152 | *allocated_size = 0; | |
153 | return NULL; | |
154 | } | |
155 | ||
156 | /** | |
157 | * ima_free_pages() - Free pages allocated by ima_alloc_pages(). | |
158 | * @ptr: Pointer to allocated pages. | |
159 | * @size: Size of allocated buffer. | |
160 | */ | |
161 | static void ima_free_pages(void *ptr, size_t size) | |
162 | { | |
163 | if (!ptr) | |
164 | return; | |
165 | free_pages((unsigned long)ptr, get_order(size)); | |
166 | } | |
167 | ||
3bcced39 DK |
168 | static struct crypto_ahash *ima_alloc_atfm(enum hash_algo algo) |
169 | { | |
170 | struct crypto_ahash *tfm = ima_ahash_tfm; | |
171 | int rc; | |
172 | ||
9a8d289f MZ |
173 | if (algo < 0 || algo >= HASH_ALGO__LAST) |
174 | algo = ima_hash_algo; | |
175 | ||
176 | if (algo != ima_hash_algo || !tfm) { | |
3bcced39 DK |
177 | tfm = crypto_alloc_ahash(hash_algo_name[algo], 0, 0); |
178 | if (!IS_ERR(tfm)) { | |
179 | if (algo == ima_hash_algo) | |
180 | ima_ahash_tfm = tfm; | |
181 | } else { | |
182 | rc = PTR_ERR(tfm); | |
183 | pr_err("Can not allocate %s (reason: %d)\n", | |
184 | hash_algo_name[algo], rc); | |
185 | } | |
186 | } | |
187 | return tfm; | |
188 | } | |
189 | ||
190 | static void ima_free_atfm(struct crypto_ahash *tfm) | |
191 | { | |
192 | if (tfm != ima_ahash_tfm) | |
193 | crypto_free_ahash(tfm); | |
194 | } | |
195 | ||
46f1414c | 196 | static inline int ahash_wait(int err, struct crypto_wait *wait) |
3bcced39 | 197 | { |
3bcced39 | 198 | |
46f1414c | 199 | err = crypto_wait_req(err, wait); |
3bcced39 | 200 | |
46f1414c | 201 | if (err) |
3bcced39 | 202 | pr_crit_ratelimited("ahash calculation failed: err: %d\n", err); |
3bcced39 DK |
203 | |
204 | return err; | |
205 | } | |
206 | ||
207 | static int ima_calc_file_hash_atfm(struct file *file, | |
208 | struct ima_digest_data *hash, | |
209 | struct crypto_ahash *tfm) | |
210 | { | |
211 | loff_t i_size, offset; | |
32c2e675 DK |
212 | char *rbuf[2] = { NULL, }; |
213 | int rc, read = 0, rbuf_len, active = 0, ahash_rc = 0; | |
3bcced39 DK |
214 | struct ahash_request *req; |
215 | struct scatterlist sg[1]; | |
46f1414c | 216 | struct crypto_wait wait; |
32c2e675 | 217 | size_t rbuf_size[2]; |
3bcced39 DK |
218 | |
219 | hash->length = crypto_ahash_digestsize(tfm); | |
220 | ||
221 | req = ahash_request_alloc(tfm, GFP_KERNEL); | |
222 | if (!req) | |
223 | return -ENOMEM; | |
224 | ||
46f1414c | 225 | crypto_init_wait(&wait); |
3bcced39 DK |
226 | ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | |
227 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
46f1414c | 228 | crypto_req_done, &wait); |
3bcced39 | 229 | |
46f1414c | 230 | rc = ahash_wait(crypto_ahash_init(req), &wait); |
3bcced39 DK |
231 | if (rc) |
232 | goto out1; | |
233 | ||
234 | i_size = i_size_read(file_inode(file)); | |
235 | ||
236 | if (i_size == 0) | |
237 | goto out2; | |
238 | ||
6edf7a89 DK |
239 | /* |
240 | * Try to allocate maximum size of memory. | |
241 | * Fail if even a single page cannot be allocated. | |
242 | */ | |
32c2e675 DK |
243 | rbuf[0] = ima_alloc_pages(i_size, &rbuf_size[0], 1); |
244 | if (!rbuf[0]) { | |
3bcced39 DK |
245 | rc = -ENOMEM; |
246 | goto out1; | |
247 | } | |
248 | ||
32c2e675 DK |
249 | /* Only allocate one buffer if that is enough. */ |
250 | if (i_size > rbuf_size[0]) { | |
251 | /* | |
252 | * Try to allocate secondary buffer. If that fails fallback to | |
253 | * using single buffering. Use previous memory allocation size | |
254 | * as baseline for possible allocation size. | |
255 | */ | |
256 | rbuf[1] = ima_alloc_pages(i_size - rbuf_size[0], | |
257 | &rbuf_size[1], 0); | |
258 | } | |
259 | ||
3bcced39 DK |
260 | if (!(file->f_mode & FMODE_READ)) { |
261 | file->f_mode |= FMODE_READ; | |
262 | read = 1; | |
263 | } | |
264 | ||
265 | for (offset = 0; offset < i_size; offset += rbuf_len) { | |
32c2e675 DK |
266 | if (!rbuf[1] && offset) { |
267 | /* Not using two buffers, and it is not the first | |
268 | * read/request, wait for the completion of the | |
269 | * previous ahash_update() request. | |
270 | */ | |
46f1414c | 271 | rc = ahash_wait(ahash_rc, &wait); |
32c2e675 DK |
272 | if (rc) |
273 | goto out3; | |
274 | } | |
275 | /* read buffer */ | |
276 | rbuf_len = min_t(loff_t, i_size - offset, rbuf_size[active]); | |
e3c4abbf DK |
277 | rc = integrity_kernel_read(file, offset, rbuf[active], |
278 | rbuf_len); | |
32c2e675 DK |
279 | if (rc != rbuf_len) |
280 | goto out3; | |
281 | ||
282 | if (rbuf[1] && offset) { | |
283 | /* Using two buffers, and it is not the first | |
284 | * read/request, wait for the completion of the | |
285 | * previous ahash_update() request. | |
286 | */ | |
46f1414c | 287 | rc = ahash_wait(ahash_rc, &wait); |
32c2e675 DK |
288 | if (rc) |
289 | goto out3; | |
3bcced39 | 290 | } |
3bcced39 | 291 | |
32c2e675 | 292 | sg_init_one(&sg[0], rbuf[active], rbuf_len); |
3bcced39 DK |
293 | ahash_request_set_crypt(req, sg, NULL, rbuf_len); |
294 | ||
32c2e675 DK |
295 | ahash_rc = crypto_ahash_update(req); |
296 | ||
297 | if (rbuf[1]) | |
298 | active = !active; /* swap buffers, if we use two */ | |
3bcced39 | 299 | } |
32c2e675 | 300 | /* wait for the last update request to complete */ |
46f1414c | 301 | rc = ahash_wait(ahash_rc, &wait); |
32c2e675 | 302 | out3: |
3bcced39 DK |
303 | if (read) |
304 | file->f_mode &= ~FMODE_READ; | |
32c2e675 DK |
305 | ima_free_pages(rbuf[0], rbuf_size[0]); |
306 | ima_free_pages(rbuf[1], rbuf_size[1]); | |
3bcced39 DK |
307 | out2: |
308 | if (!rc) { | |
309 | ahash_request_set_crypt(req, NULL, hash->digest, 0); | |
46f1414c | 310 | rc = ahash_wait(crypto_ahash_final(req), &wait); |
3bcced39 DK |
311 | } |
312 | out1: | |
313 | ahash_request_free(req); | |
314 | return rc; | |
315 | } | |
316 | ||
317 | static int ima_calc_file_ahash(struct file *file, struct ima_digest_data *hash) | |
318 | { | |
319 | struct crypto_ahash *tfm; | |
320 | int rc; | |
321 | ||
322 | tfm = ima_alloc_atfm(hash->algo); | |
323 | if (IS_ERR(tfm)) | |
324 | return PTR_ERR(tfm); | |
325 | ||
326 | rc = ima_calc_file_hash_atfm(file, hash, tfm); | |
327 | ||
328 | ima_free_atfm(tfm); | |
329 | ||
330 | return rc; | |
331 | } | |
332 | ||
c7c8bb23 DK |
333 | static int ima_calc_file_hash_tfm(struct file *file, |
334 | struct ima_digest_data *hash, | |
335 | struct crypto_shash *tfm) | |
3323eec9 | 336 | { |
16bfa38b | 337 | loff_t i_size, offset = 0; |
3323eec9 | 338 | char *rbuf; |
2fe5d6de | 339 | int rc, read = 0; |
357aabed | 340 | SHASH_DESC_ON_STACK(shash, tfm); |
3323eec9 | 341 | |
357aabed BW |
342 | shash->tfm = tfm; |
343 | shash->flags = 0; | |
76bb28f6 | 344 | |
723326b9 DK |
345 | hash->length = crypto_shash_digestsize(tfm); |
346 | ||
357aabed | 347 | rc = crypto_shash_init(shash); |
3323eec9 MZ |
348 | if (rc != 0) |
349 | return rc; | |
350 | ||
1d91ac62 DK |
351 | i_size = i_size_read(file_inode(file)); |
352 | ||
353 | if (i_size == 0) | |
3323eec9 | 354 | goto out; |
1d91ac62 DK |
355 | |
356 | rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL); | |
357 | if (!rbuf) | |
358 | return -ENOMEM; | |
359 | ||
2fe5d6de MZ |
360 | if (!(file->f_mode & FMODE_READ)) { |
361 | file->f_mode |= FMODE_READ; | |
362 | read = 1; | |
363 | } | |
1d91ac62 | 364 | |
3323eec9 MZ |
365 | while (offset < i_size) { |
366 | int rbuf_len; | |
367 | ||
e3c4abbf | 368 | rbuf_len = integrity_kernel_read(file, offset, rbuf, PAGE_SIZE); |
3323eec9 MZ |
369 | if (rbuf_len < 0) { |
370 | rc = rbuf_len; | |
371 | break; | |
372 | } | |
16bfa38b MZ |
373 | if (rbuf_len == 0) |
374 | break; | |
3323eec9 | 375 | offset += rbuf_len; |
3323eec9 | 376 | |
357aabed | 377 | rc = crypto_shash_update(shash, rbuf, rbuf_len); |
3323eec9 MZ |
378 | if (rc) |
379 | break; | |
380 | } | |
2fe5d6de MZ |
381 | if (read) |
382 | file->f_mode &= ~FMODE_READ; | |
1d91ac62 | 383 | kfree(rbuf); |
3323eec9 | 384 | out: |
1d91ac62 | 385 | if (!rc) |
357aabed | 386 | rc = crypto_shash_final(shash, hash->digest); |
3323eec9 MZ |
387 | return rc; |
388 | } | |
389 | ||
3bcced39 | 390 | static int ima_calc_file_shash(struct file *file, struct ima_digest_data *hash) |
c7c8bb23 | 391 | { |
723326b9 | 392 | struct crypto_shash *tfm; |
c7c8bb23 DK |
393 | int rc; |
394 | ||
723326b9 DK |
395 | tfm = ima_alloc_tfm(hash->algo); |
396 | if (IS_ERR(tfm)) | |
397 | return PTR_ERR(tfm); | |
c7c8bb23 DK |
398 | |
399 | rc = ima_calc_file_hash_tfm(file, hash, tfm); | |
400 | ||
723326b9 | 401 | ima_free_tfm(tfm); |
c7c8bb23 DK |
402 | |
403 | return rc; | |
404 | } | |
405 | ||
3bcced39 DK |
406 | /* |
407 | * ima_calc_file_hash - calculate file hash | |
408 | * | |
409 | * Asynchronous hash (ahash) allows using HW acceleration for calculating | |
410 | * a hash. ahash performance varies for different data sizes on different | |
411 | * crypto accelerators. shash performance might be better for smaller files. | |
412 | * The 'ima.ahash_minsize' module parameter allows specifying the best | |
413 | * minimum file size for using ahash on the system. | |
414 | * | |
415 | * If the ima.ahash_minsize parameter is not specified, this function uses | |
416 | * shash for the hash calculation. If ahash fails, it falls back to using | |
417 | * shash. | |
418 | */ | |
419 | int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) | |
420 | { | |
421 | loff_t i_size; | |
422 | int rc; | |
423 | ||
f3cc6b25 MZ |
424 | /* |
425 | * For consistency, fail file's opened with the O_DIRECT flag on | |
426 | * filesystems mounted with/without DAX option. | |
427 | */ | |
428 | if (file->f_flags & O_DIRECT) { | |
429 | hash->length = hash_digest_size[ima_hash_algo]; | |
430 | hash->algo = ima_hash_algo; | |
431 | return -EINVAL; | |
432 | } | |
433 | ||
3bcced39 DK |
434 | i_size = i_size_read(file_inode(file)); |
435 | ||
436 | if (ima_ahash_minsize && i_size >= ima_ahash_minsize) { | |
437 | rc = ima_calc_file_ahash(file, hash); | |
438 | if (!rc) | |
439 | return 0; | |
440 | } | |
441 | ||
442 | return ima_calc_file_shash(file, hash); | |
443 | } | |
444 | ||
3323eec9 | 445 | /* |
a71dc65d | 446 | * Calculate the hash of template data |
3323eec9 | 447 | */ |
a71dc65d | 448 | static int ima_calc_field_array_hash_tfm(struct ima_field_data *field_data, |
b6f8f16f | 449 | struct ima_template_desc *td, |
a71dc65d RS |
450 | int num_fields, |
451 | struct ima_digest_data *hash, | |
452 | struct crypto_shash *tfm) | |
3323eec9 | 453 | { |
357aabed | 454 | SHASH_DESC_ON_STACK(shash, tfm); |
a71dc65d | 455 | int rc, i; |
3323eec9 | 456 | |
357aabed BW |
457 | shash->tfm = tfm; |
458 | shash->flags = 0; | |
3323eec9 | 459 | |
ea593993 | 460 | hash->length = crypto_shash_digestsize(tfm); |
c7c8bb23 | 461 | |
357aabed | 462 | rc = crypto_shash_init(shash); |
a71dc65d RS |
463 | if (rc != 0) |
464 | return rc; | |
465 | ||
466 | for (i = 0; i < num_fields; i++) { | |
e3b64c26 RS |
467 | u8 buffer[IMA_EVENT_NAME_LEN_MAX + 1] = { 0 }; |
468 | u8 *data_to_hash = field_data[i].data; | |
469 | u32 datalen = field_data[i].len; | |
98e1d55d AS |
470 | u32 datalen_to_hash = |
471 | !ima_canonical_fmt ? datalen : cpu_to_le32(datalen); | |
e3b64c26 | 472 | |
b6f8f16f | 473 | if (strcmp(td->name, IMA_TEMPLATE_IMA_NAME) != 0) { |
357aabed | 474 | rc = crypto_shash_update(shash, |
98e1d55d AS |
475 | (const u8 *) &datalen_to_hash, |
476 | sizeof(datalen_to_hash)); | |
b6f8f16f RS |
477 | if (rc) |
478 | break; | |
e3b64c26 RS |
479 | } else if (strcmp(td->fields[i]->field_id, "n") == 0) { |
480 | memcpy(buffer, data_to_hash, datalen); | |
481 | data_to_hash = buffer; | |
482 | datalen = IMA_EVENT_NAME_LEN_MAX + 1; | |
b6f8f16f | 483 | } |
357aabed | 484 | rc = crypto_shash_update(shash, data_to_hash, datalen); |
a71dc65d RS |
485 | if (rc) |
486 | break; | |
487 | } | |
488 | ||
489 | if (!rc) | |
357aabed | 490 | rc = crypto_shash_final(shash, hash->digest); |
a71dc65d RS |
491 | |
492 | return rc; | |
3323eec9 MZ |
493 | } |
494 | ||
b6f8f16f RS |
495 | int ima_calc_field_array_hash(struct ima_field_data *field_data, |
496 | struct ima_template_desc *desc, int num_fields, | |
a71dc65d | 497 | struct ima_digest_data *hash) |
ea593993 DK |
498 | { |
499 | struct crypto_shash *tfm; | |
500 | int rc; | |
501 | ||
502 | tfm = ima_alloc_tfm(hash->algo); | |
503 | if (IS_ERR(tfm)) | |
504 | return PTR_ERR(tfm); | |
505 | ||
b6f8f16f RS |
506 | rc = ima_calc_field_array_hash_tfm(field_data, desc, num_fields, |
507 | hash, tfm); | |
ea593993 DK |
508 | |
509 | ima_free_tfm(tfm); | |
510 | ||
511 | return rc; | |
512 | } | |
513 | ||
98304bcf MZ |
514 | static int calc_buffer_ahash_atfm(const void *buf, loff_t len, |
515 | struct ima_digest_data *hash, | |
516 | struct crypto_ahash *tfm) | |
517 | { | |
518 | struct ahash_request *req; | |
519 | struct scatterlist sg; | |
46f1414c | 520 | struct crypto_wait wait; |
98304bcf MZ |
521 | int rc, ahash_rc = 0; |
522 | ||
523 | hash->length = crypto_ahash_digestsize(tfm); | |
524 | ||
525 | req = ahash_request_alloc(tfm, GFP_KERNEL); | |
526 | if (!req) | |
527 | return -ENOMEM; | |
528 | ||
46f1414c | 529 | crypto_init_wait(&wait); |
98304bcf MZ |
530 | ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG | |
531 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
46f1414c | 532 | crypto_req_done, &wait); |
98304bcf | 533 | |
46f1414c | 534 | rc = ahash_wait(crypto_ahash_init(req), &wait); |
98304bcf MZ |
535 | if (rc) |
536 | goto out; | |
537 | ||
538 | sg_init_one(&sg, buf, len); | |
539 | ahash_request_set_crypt(req, &sg, NULL, len); | |
540 | ||
541 | ahash_rc = crypto_ahash_update(req); | |
542 | ||
543 | /* wait for the update request to complete */ | |
46f1414c | 544 | rc = ahash_wait(ahash_rc, &wait); |
98304bcf MZ |
545 | if (!rc) { |
546 | ahash_request_set_crypt(req, NULL, hash->digest, 0); | |
46f1414c | 547 | rc = ahash_wait(crypto_ahash_final(req), &wait); |
98304bcf MZ |
548 | } |
549 | out: | |
550 | ahash_request_free(req); | |
551 | return rc; | |
552 | } | |
553 | ||
554 | static int calc_buffer_ahash(const void *buf, loff_t len, | |
555 | struct ima_digest_data *hash) | |
556 | { | |
557 | struct crypto_ahash *tfm; | |
558 | int rc; | |
559 | ||
560 | tfm = ima_alloc_atfm(hash->algo); | |
561 | if (IS_ERR(tfm)) | |
562 | return PTR_ERR(tfm); | |
563 | ||
564 | rc = calc_buffer_ahash_atfm(buf, len, hash, tfm); | |
565 | ||
566 | ima_free_atfm(tfm); | |
567 | ||
568 | return rc; | |
569 | } | |
570 | ||
11d7646d DK |
571 | static int calc_buffer_shash_tfm(const void *buf, loff_t size, |
572 | struct ima_digest_data *hash, | |
573 | struct crypto_shash *tfm) | |
574 | { | |
575 | SHASH_DESC_ON_STACK(shash, tfm); | |
576 | unsigned int len; | |
577 | int rc; | |
578 | ||
579 | shash->tfm = tfm; | |
580 | shash->flags = 0; | |
581 | ||
582 | hash->length = crypto_shash_digestsize(tfm); | |
583 | ||
584 | rc = crypto_shash_init(shash); | |
585 | if (rc != 0) | |
586 | return rc; | |
587 | ||
588 | while (size) { | |
589 | len = size < PAGE_SIZE ? size : PAGE_SIZE; | |
590 | rc = crypto_shash_update(shash, buf, len); | |
591 | if (rc) | |
592 | break; | |
593 | buf += len; | |
594 | size -= len; | |
595 | } | |
596 | ||
597 | if (!rc) | |
598 | rc = crypto_shash_final(shash, hash->digest); | |
599 | return rc; | |
600 | } | |
601 | ||
98304bcf MZ |
602 | static int calc_buffer_shash(const void *buf, loff_t len, |
603 | struct ima_digest_data *hash) | |
11d7646d DK |
604 | { |
605 | struct crypto_shash *tfm; | |
606 | int rc; | |
607 | ||
608 | tfm = ima_alloc_tfm(hash->algo); | |
609 | if (IS_ERR(tfm)) | |
610 | return PTR_ERR(tfm); | |
611 | ||
612 | rc = calc_buffer_shash_tfm(buf, len, hash, tfm); | |
613 | ||
614 | ima_free_tfm(tfm); | |
615 | return rc; | |
616 | } | |
617 | ||
98304bcf MZ |
618 | int ima_calc_buffer_hash(const void *buf, loff_t len, |
619 | struct ima_digest_data *hash) | |
620 | { | |
621 | int rc; | |
622 | ||
623 | if (ima_ahash_minsize && len >= ima_ahash_minsize) { | |
624 | rc = calc_buffer_ahash(buf, len, hash); | |
625 | if (!rc) | |
626 | return 0; | |
627 | } | |
628 | ||
629 | return calc_buffer_shash(buf, len, hash); | |
630 | } | |
631 | ||
932995f0 | 632 | static void __init ima_pcrread(int idx, u8 *pcr) |
3323eec9 MZ |
633 | { |
634 | if (!ima_used_chip) | |
635 | return; | |
636 | ||
637 | if (tpm_pcr_read(TPM_ANY_NUM, idx, pcr) != 0) | |
20ee451f | 638 | pr_err("Error Communicating to TPM chip\n"); |
3323eec9 MZ |
639 | } |
640 | ||
641 | /* | |
642 | * Calculate the boot aggregate hash | |
643 | */ | |
09ef5435 DK |
644 | static int __init ima_calc_boot_aggregate_tfm(char *digest, |
645 | struct crypto_shash *tfm) | |
3323eec9 | 646 | { |
140d8022 | 647 | u8 pcr_i[TPM_DIGEST_SIZE]; |
3323eec9 | 648 | int rc, i; |
357aabed | 649 | SHASH_DESC_ON_STACK(shash, tfm); |
76bb28f6 | 650 | |
357aabed BW |
651 | shash->tfm = tfm; |
652 | shash->flags = 0; | |
3323eec9 | 653 | |
357aabed | 654 | rc = crypto_shash_init(shash); |
3323eec9 MZ |
655 | if (rc != 0) |
656 | return rc; | |
657 | ||
658 | /* cumulative sha1 over tpm registers 0-7 */ | |
659 | for (i = TPM_PCR0; i < TPM_PCR8; i++) { | |
660 | ima_pcrread(i, pcr_i); | |
661 | /* now accumulate with current aggregate */ | |
357aabed | 662 | rc = crypto_shash_update(shash, pcr_i, TPM_DIGEST_SIZE); |
3323eec9 MZ |
663 | } |
664 | if (!rc) | |
357aabed | 665 | crypto_shash_final(shash, digest); |
3323eec9 MZ |
666 | return rc; |
667 | } | |
09ef5435 DK |
668 | |
669 | int __init ima_calc_boot_aggregate(struct ima_digest_data *hash) | |
670 | { | |
671 | struct crypto_shash *tfm; | |
672 | int rc; | |
673 | ||
674 | tfm = ima_alloc_tfm(hash->algo); | |
675 | if (IS_ERR(tfm)) | |
676 | return PTR_ERR(tfm); | |
677 | ||
678 | hash->length = crypto_shash_digestsize(tfm); | |
679 | rc = ima_calc_boot_aggregate_tfm(hash->digest, tfm); | |
680 | ||
681 | ima_free_tfm(tfm); | |
682 | ||
683 | return rc; | |
684 | } |