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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Integrity Measurement Architecture
4 *
5 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
6 *
7 * Authors:
8 * Reiner Sailer <[email protected]>
9 * Serge Hallyn <[email protected]>
10 * Kylene Hall <[email protected]>
11 * Mimi Zohar <[email protected]>
12 *
13 * File: ima_main.c
14 * implements the IMA hooks: ima_bprm_check, ima_file_mmap,
15 * and ima_file_check.
16 */
17
18#include <linux/module.h>
19#include <linux/file.h>
20#include <linux/binfmts.h>
21#include <linux/kernel_read_file.h>
22#include <linux/mount.h>
23#include <linux/mman.h>
24#include <linux/slab.h>
25#include <linux/xattr.h>
26#include <linux/ima.h>
27#include <linux/fs.h>
28#include <linux/iversion.h>
29#include <linux/evm.h>
30#include <linux/crash_dump.h>
31
32#include "ima.h"
33
34#ifdef CONFIG_IMA_APPRAISE
35int ima_appraise = IMA_APPRAISE_ENFORCE;
36#else
37int ima_appraise;
38#endif
39
40int __ro_after_init ima_hash_algo = HASH_ALGO_SHA1;
41static int hash_setup_done;
42static int ima_disabled __ro_after_init;
43
44static struct notifier_block ima_lsm_policy_notifier = {
45 .notifier_call = ima_lsm_policy_change,
46};
47
48static int __init ima_setup(char *str)
49{
50 if (!is_kdump_kernel()) {
51 pr_info("Warning: ima setup option only permitted in kdump");
52 return 1;
53 }
54
55 if (strncmp(str, "off", 3) == 0)
56 ima_disabled = 1;
57 else if (strncmp(str, "on", 2) == 0)
58 ima_disabled = 0;
59 else
60 pr_err("Invalid ima setup option: \"%s\" , please specify ima=on|off.", str);
61
62 return 1;
63}
64__setup("ima=", ima_setup);
65
66static int __init hash_setup(char *str)
67{
68 struct ima_template_desc *template_desc = ima_template_desc_current();
69 int i;
70
71 if (hash_setup_done)
72 return 1;
73
74 if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
75 if (strncmp(str, "sha1", 4) == 0) {
76 ima_hash_algo = HASH_ALGO_SHA1;
77 } else if (strncmp(str, "md5", 3) == 0) {
78 ima_hash_algo = HASH_ALGO_MD5;
79 } else {
80 pr_err("invalid hash algorithm \"%s\" for template \"%s\"",
81 str, IMA_TEMPLATE_IMA_NAME);
82 return 1;
83 }
84 goto out;
85 }
86
87 i = match_string(hash_algo_name, HASH_ALGO__LAST, str);
88 if (i < 0) {
89 pr_err("invalid hash algorithm \"%s\"", str);
90 return 1;
91 }
92
93 ima_hash_algo = i;
94out:
95 hash_setup_done = 1;
96 return 1;
97}
98__setup("ima_hash=", hash_setup);
99
100enum hash_algo ima_get_current_hash_algo(void)
101{
102 return ima_hash_algo;
103}
104
105/* Prevent mmap'ing a file execute that is already mmap'ed write */
106static int mmap_violation_check(enum ima_hooks func, struct file *file,
107 char **pathbuf, const char **pathname,
108 char *filename)
109{
110 struct inode *inode;
111 int rc = 0;
112
113 if ((func == MMAP_CHECK || func == MMAP_CHECK_REQPROT) &&
114 mapping_writably_mapped(file->f_mapping)) {
115 rc = -ETXTBSY;
116 inode = file_inode(file);
117
118 if (!*pathbuf) /* ima_rdwr_violation possibly pre-fetched */
119 *pathname = ima_d_path(&file->f_path, pathbuf,
120 filename);
121 integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, *pathname,
122 "mmap_file", "mmapped_writers", rc, 0);
123 }
124 return rc;
125}
126
127/*
128 * ima_rdwr_violation_check
129 *
130 * Only invalidate the PCR for measured files:
131 * - Opening a file for write when already open for read,
132 * results in a time of measure, time of use (ToMToU) error.
133 * - Opening a file for read when already open for write,
134 * could result in a file measurement error.
135 *
136 */
137static void ima_rdwr_violation_check(struct file *file,
138 struct ima_iint_cache *iint,
139 int must_measure,
140 char **pathbuf,
141 const char **pathname,
142 char *filename)
143{
144 struct inode *inode = file_inode(file);
145 fmode_t mode = file->f_mode;
146 bool send_tomtou = false, send_writers = false;
147
148 if (mode & FMODE_WRITE) {
149 if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
150 if (!iint)
151 iint = ima_iint_find(inode);
152
153 /* IMA_MEASURE is set from reader side */
154 if (iint && test_and_clear_bit(IMA_MAY_EMIT_TOMTOU,
155 &iint->atomic_flags))
156 send_tomtou = true;
157 }
158 } else {
159 if (must_measure)
160 set_bit(IMA_MAY_EMIT_TOMTOU, &iint->atomic_flags);
161
162 /* Limit number of open_writers violations */
163 if (inode_is_open_for_write(inode) && must_measure) {
164 if (!test_and_set_bit(IMA_EMITTED_OPENWRITERS,
165 &iint->atomic_flags))
166 send_writers = true;
167 }
168 }
169
170 if (!send_tomtou && !send_writers)
171 return;
172
173 *pathname = ima_d_path(&file->f_path, pathbuf, filename);
174
175 if (send_tomtou)
176 ima_add_violation(file, *pathname, iint,
177 "invalid_pcr", "ToMToU");
178 if (send_writers)
179 ima_add_violation(file, *pathname, iint,
180 "invalid_pcr", "open_writers");
181}
182
183/*
184 * Detect file change based on STATX_CHANGE_COOKIE, when supported, and
185 * fallback to detecting file change based on i_version. On filesystems
186 * which do not support either, assume the file changed.
187 */
188static bool ima_detect_file_change(struct ima_iint_cache *iint,
189 struct inode *inode, struct file *file)
190{
191 struct kstat stat;
192 int result;
193
194 result = vfs_getattr_nosec(&file->f_path, &stat, STATX_CHANGE_COOKIE,
195 AT_STATX_SYNC_AS_STAT);
196
197 if (!result && stat.result_mask & STATX_CHANGE_COOKIE)
198 return stat.change_cookie != iint->real_inode.version;
199
200 if (IS_I_VERSION(inode))
201 return !inode_eq_iversion(inode, iint->real_inode.version);
202
203 return true;
204}
205
206static void ima_check_last_writer(struct ima_iint_cache *iint,
207 struct inode *inode, struct file *file)
208{
209 fmode_t mode = file->f_mode;
210 bool update;
211
212 if (!(mode & FMODE_WRITE))
213 return;
214
215 mutex_lock(&iint->mutex);
216 if (atomic_read(&inode->i_writecount) == 1) {
217 clear_bit(IMA_EMITTED_OPENWRITERS, &iint->atomic_flags);
218
219 update = test_and_clear_bit(IMA_UPDATE_XATTR,
220 &iint->atomic_flags);
221
222 if (iint->flags & IMA_NEW_FILE ||
223 ima_detect_file_change(iint, inode, file)) {
224 iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
225 iint->measured_pcrs = 0;
226 if (update)
227 ima_update_xattr(iint, file);
228 }
229 }
230 mutex_unlock(&iint->mutex);
231}
232
233/**
234 * ima_file_free - called on __fput()
235 * @file: pointer to file structure being freed
236 *
237 * Flag files that changed, based on i_version
238 */
239static void ima_file_free(struct file *file)
240{
241 struct inode *inode = file_inode(file);
242 struct ima_iint_cache *iint;
243
244 if (!ima_policy_flag || !S_ISREG(inode->i_mode))
245 return;
246
247 iint = ima_iint_find(inode);
248 if (!iint)
249 return;
250
251 ima_check_last_writer(iint, inode, file);
252}
253
254static int process_measurement(struct file *file, const struct cred *cred,
255 struct lsm_prop *prop, char *buf, loff_t size,
256 int mask, enum ima_hooks func,
257 enum kernel_read_file_id read_id,
258 bool bprm_is_check)
259{
260 struct inode *real_inode, *inode = file_inode(file);
261 struct ima_iint_cache *iint = NULL;
262 struct ima_template_desc *template_desc = NULL;
263 struct inode *metadata_inode;
264 char *pathbuf = NULL;
265 char filename[NAME_MAX];
266 const char *pathname = NULL;
267 int rc = 0, action, must_appraise = 0;
268 int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
269 struct evm_ima_xattr_data *xattr_value = NULL;
270 struct modsig *modsig = NULL;
271 int xattr_len = 0;
272 bool violation_check;
273 enum hash_algo hash_algo;
274 unsigned int allowed_algos = 0;
275
276 if (!ima_policy_flag || !S_ISREG(inode->i_mode))
277 return 0;
278
279 /* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
280 * bitmask based on the appraise/audit/measurement policy.
281 * Included is the appraise submask.
282 */
283 action = ima_get_action(file_mnt_idmap(file), inode, cred, prop,
284 mask, func, &pcr, &template_desc, NULL,
285 &allowed_algos);
286 violation_check = ((func == FILE_CHECK || func == MMAP_CHECK ||
287 func == MMAP_CHECK_REQPROT) &&
288 (ima_policy_flag & IMA_MEASURE) &&
289 ((action & IMA_MEASURE) ||
290 (file->f_mode & FMODE_WRITE)));
291 if (!action && !violation_check)
292 return 0;
293
294 must_appraise = action & IMA_APPRAISE;
295
296 /* Is the appraise rule hook specific? */
297 if (action & IMA_FILE_APPRAISE)
298 func = FILE_CHECK;
299
300 inode_lock(inode);
301
302 if (action) {
303 iint = ima_inode_get(inode);
304 if (!iint)
305 rc = -ENOMEM;
306 }
307
308 if (!rc && violation_check)
309 ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
310 &pathbuf, &pathname, filename);
311
312 inode_unlock(inode);
313
314 if (rc)
315 goto out;
316 if (!action)
317 goto out;
318
319 mutex_lock(&iint->mutex);
320
321 if (test_and_clear_bit(IMA_CHANGE_ATTR, &iint->atomic_flags))
322 /*
323 * Reset appraisal flags (action and non-action rule-specific)
324 * if ima_inode_post_setattr was called.
325 */
326 iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
327 IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
328 IMA_NONACTION_RULE_FLAGS);
329
330 /*
331 * Re-evaulate the file if either the xattr has changed or the
332 * kernel has no way of detecting file change on the filesystem.
333 * (Limited to privileged mounted filesystems.)
334 */
335 if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags) ||
336 ((inode->i_sb->s_iflags & SB_I_IMA_UNVERIFIABLE_SIGNATURE) &&
337 !(inode->i_sb->s_iflags & SB_I_UNTRUSTED_MOUNTER) &&
338 !(action & IMA_FAIL_UNVERIFIABLE_SIGS))) {
339 iint->flags &= ~IMA_DONE_MASK;
340 iint->measured_pcrs = 0;
341 }
342
343 /*
344 * On stacked filesystems, detect and re-evaluate file data and
345 * metadata changes.
346 */
347 real_inode = d_real_inode(file_dentry(file));
348 if (real_inode != inode &&
349 (action & IMA_DO_MASK) && (iint->flags & IMA_DONE_MASK)) {
350 if (!IS_I_VERSION(real_inode) ||
351 integrity_inode_attrs_changed(&iint->real_inode,
352 real_inode)) {
353 iint->flags &= ~IMA_DONE_MASK;
354 iint->measured_pcrs = 0;
355 }
356
357 /*
358 * Reset the EVM status when metadata changed.
359 */
360 metadata_inode = d_inode(d_real(file_dentry(file),
361 D_REAL_METADATA));
362 if (evm_metadata_changed(inode, metadata_inode))
363 iint->flags &= ~(IMA_APPRAISED |
364 IMA_APPRAISED_SUBMASK);
365 }
366
367 /* Determine if already appraised/measured based on bitmask
368 * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
369 * IMA_AUDIT, IMA_AUDITED)
370 */
371 iint->flags |= action;
372 action &= IMA_DO_MASK;
373 action &= ~((iint->flags & (IMA_DONE_MASK ^ IMA_MEASURED)) >> 1);
374
375 /* If target pcr is already measured, unset IMA_MEASURE action */
376 if ((action & IMA_MEASURE) && (iint->measured_pcrs & (0x1 << pcr)))
377 action ^= IMA_MEASURE;
378
379 /* HASH sets the digital signature and update flags, nothing else */
380 if ((action & IMA_HASH) &&
381 !(test_bit(IMA_DIGSIG, &iint->atomic_flags))) {
382 xattr_len = ima_read_xattr(file_dentry(file),
383 &xattr_value, xattr_len);
384 if ((xattr_value && xattr_len > 2) &&
385 (xattr_value->type == EVM_IMA_XATTR_DIGSIG))
386 set_bit(IMA_DIGSIG, &iint->atomic_flags);
387 iint->flags |= IMA_HASHED;
388 action ^= IMA_HASH;
389 set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
390 }
391
392 /* Nothing to do, just return existing appraised status */
393 if (!action) {
394 if (must_appraise) {
395 rc = mmap_violation_check(func, file, &pathbuf,
396 &pathname, filename);
397 if (!rc)
398 rc = ima_get_cache_status(iint, func);
399 }
400 goto out_locked;
401 }
402
403 if ((action & IMA_APPRAISE_SUBMASK) ||
404 strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0) {
405 /* read 'security.ima' */
406 xattr_len = ima_read_xattr(file_dentry(file),
407 &xattr_value, xattr_len);
408
409 /*
410 * Read the appended modsig if allowed by the policy, and allow
411 * an additional measurement list entry, if needed, based on the
412 * template format and whether the file was already measured.
413 */
414 if (iint->flags & IMA_MODSIG_ALLOWED) {
415 rc = ima_read_modsig(func, buf, size, &modsig);
416
417 if (!rc && ima_template_has_modsig(template_desc) &&
418 iint->flags & IMA_MEASURED)
419 action |= IMA_MEASURE;
420 }
421 }
422
423 hash_algo = ima_get_hash_algo(xattr_value, xattr_len);
424
425 rc = ima_collect_measurement(iint, file, buf, size, hash_algo, modsig);
426 if (rc != 0 && rc != -EBADF && rc != -EINVAL)
427 goto out_locked;
428
429 /* Defer measuring/appraising kernel modules to READING_MODULE */
430 if (read_id == READING_MODULE_COMPRESSED) {
431 must_appraise = 0;
432 goto out_locked;
433 }
434
435 if (!pathbuf) /* ima_rdwr_violation possibly pre-fetched */
436 pathname = ima_d_path(&file->f_path, &pathbuf, filename);
437
438 if (action & IMA_MEASURE)
439 ima_store_measurement(iint, file, pathname,
440 xattr_value, xattr_len, modsig, pcr,
441 template_desc);
442 if (rc == 0 && (action & IMA_APPRAISE_SUBMASK)) {
443 rc = ima_check_blacklist(iint, modsig, pcr);
444 if (rc != -EPERM) {
445 inode_lock(inode);
446 rc = ima_appraise_measurement(func, iint, file,
447 pathname, xattr_value,
448 xattr_len, modsig,
449 bprm_is_check);
450 inode_unlock(inode);
451 }
452 if (!rc)
453 rc = mmap_violation_check(func, file, &pathbuf,
454 &pathname, filename);
455 }
456 if (action & IMA_AUDIT)
457 ima_audit_measurement(iint, pathname);
458
459 if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))
460 rc = 0;
461
462 /* Ensure the digest was generated using an allowed algorithm */
463 if (rc == 0 && must_appraise && allowed_algos != 0 &&
464 (allowed_algos & (1U << hash_algo)) == 0) {
465 rc = -EACCES;
466
467 integrity_audit_msg(AUDIT_INTEGRITY_DATA, file_inode(file),
468 pathname, "collect_data",
469 "denied-hash-algorithm", rc, 0);
470 }
471out_locked:
472 if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) &&
473 !(iint->flags & IMA_NEW_FILE))
474 rc = -EACCES;
475 mutex_unlock(&iint->mutex);
476 kfree(xattr_value);
477 ima_free_modsig(modsig);
478out:
479 if (pathbuf)
480 __putname(pathbuf);
481 if (must_appraise) {
482 if (rc && (ima_appraise & IMA_APPRAISE_ENFORCE))
483 return -EACCES;
484 if (file->f_mode & FMODE_WRITE)
485 set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
486 }
487 return 0;
488}
489
490/**
491 * ima_file_mmap - based on policy, collect/store measurement.
492 * @file: pointer to the file to be measured (May be NULL)
493 * @reqprot: protection requested by the application
494 * @prot: protection that will be applied by the kernel
495 * @flags: operational flags
496 *
497 * Measure files being mmapped executable based on the ima_must_measure()
498 * policy decision.
499 *
500 * On success return 0. On integrity appraisal error, assuming the file
501 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
502 */
503static int ima_file_mmap(struct file *file, unsigned long reqprot,
504 unsigned long prot, unsigned long flags)
505{
506 struct lsm_prop prop;
507 int ret;
508
509 if (!file)
510 return 0;
511
512 security_current_getlsmprop_subj(&prop);
513
514 if (reqprot & PROT_EXEC) {
515 ret = process_measurement(file, current_cred(), &prop, NULL,
516 0, MAY_EXEC, MMAP_CHECK_REQPROT, 0,
517 false);
518 if (ret)
519 return ret;
520 }
521
522 if (prot & PROT_EXEC)
523 return process_measurement(file, current_cred(), &prop, NULL,
524 0, MAY_EXEC, MMAP_CHECK, 0, false);
525
526 return 0;
527}
528
529/**
530 * ima_file_mprotect - based on policy, limit mprotect change
531 * @vma: vm_area_struct protection is set to
532 * @reqprot: protection requested by the application
533 * @prot: protection that will be applied by the kernel
534 *
535 * Files can be mmap'ed read/write and later changed to execute to circumvent
536 * IMA's mmap appraisal policy rules. Due to locking issues (mmap semaphore
537 * would be taken before i_mutex), files can not be measured or appraised at
538 * this point. Eliminate this integrity gap by denying the mprotect
539 * PROT_EXECUTE change, if an mmap appraise policy rule exists.
540 *
541 * On mprotect change success, return 0. On failure, return -EACESS.
542 */
543static int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
544 unsigned long prot)
545{
546 struct ima_template_desc *template = NULL;
547 struct file *file;
548 char filename[NAME_MAX];
549 char *pathbuf = NULL;
550 const char *pathname = NULL;
551 struct inode *inode;
552 struct lsm_prop prop;
553 int result = 0;
554 int action;
555 int pcr;
556
557 /* Is mprotect making an mmap'ed file executable? */
558 if (!(ima_policy_flag & IMA_APPRAISE) || !vma->vm_file ||
559 !(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))
560 return 0;
561
562 security_current_getlsmprop_subj(&prop);
563 inode = file_inode(vma->vm_file);
564 action = ima_get_action(file_mnt_idmap(vma->vm_file), inode,
565 current_cred(), &prop, MAY_EXEC, MMAP_CHECK,
566 &pcr, &template, NULL, NULL);
567 action |= ima_get_action(file_mnt_idmap(vma->vm_file), inode,
568 current_cred(), &prop, MAY_EXEC,
569 MMAP_CHECK_REQPROT, &pcr, &template, NULL,
570 NULL);
571
572 /* Is the mmap'ed file in policy? */
573 if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
574 return 0;
575
576 if (action & IMA_APPRAISE_SUBMASK)
577 result = -EPERM;
578
579 file = vma->vm_file;
580 pathname = ima_d_path(&file->f_path, &pathbuf, filename);
581 integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, pathname,
582 "collect_data", "failed-mprotect", result, 0);
583 if (pathbuf)
584 __putname(pathbuf);
585
586 return result;
587}
588
589/**
590 * ima_bprm_check - based on policy, collect/store measurement.
591 * @bprm: contains the linux_binprm structure
592 *
593 * The OS protects against an executable file, already open for write,
594 * from being executed in deny_write_access() and an executable file,
595 * already open for execute, from being modified in get_write_access().
596 * So we can be certain that what we verify and measure here is actually
597 * what is being executed.
598 *
599 * On success return 0. On integrity appraisal error, assuming the file
600 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
601 */
602static int ima_bprm_check(struct linux_binprm *bprm)
603{
604 struct lsm_prop prop;
605
606 security_current_getlsmprop_subj(&prop);
607 return process_measurement(bprm->file, current_cred(),
608 &prop, NULL, 0, MAY_EXEC, BPRM_CHECK, 0,
609 bprm->is_check);
610}
611
612/**
613 * ima_creds_check - based on policy, collect/store measurement.
614 * @bprm: contains the linux_binprm structure
615 * @file: contains the file descriptor of the binary being executed
616 *
617 * The OS protects against an executable file, already open for write,
618 * from being executed in deny_write_access() and an executable file,
619 * already open for execute, from being modified in get_write_access().
620 * So we can be certain that what we verify and measure here is actually
621 * what is being executed.
622 *
623 * The difference from ima_bprm_check() is that ima_creds_check() is invoked
624 * only after determining the final binary to be executed without interpreter,
625 * and not when searching for intermediate binaries. The reason is that since
626 * commit 56305aa9b6fab ("exec: Compute file based creds only once"), the
627 * credentials to be applied to the process are calculated only at that stage
628 * (bprm_creds_from_file security hook instead of bprm_check_security).
629 *
630 * On success return 0. On integrity appraisal error, assuming the file
631 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
632 */
633static int ima_creds_check(struct linux_binprm *bprm, const struct file *file)
634{
635 struct lsm_prop prop;
636
637 security_current_getlsmprop_subj(&prop);
638 return process_measurement((struct file *)file, bprm->cred, &prop, NULL,
639 0, MAY_EXEC, CREDS_CHECK, 0, false);
640}
641
642/**
643 * ima_bprm_creds_for_exec - collect/store/appraise measurement.
644 * @bprm: contains the linux_binprm structure
645 *
646 * Based on the IMA policy and the execveat(2) AT_EXECVE_CHECK flag, measure
647 * and appraise the integrity of a file to be executed by script interpreters.
648 * Unlike any of the other LSM hooks where the kernel enforces file integrity,
649 * enforcing file integrity is left up to the discretion of the script
650 * interpreter (userspace).
651 *
652 * On success return 0. On integrity appraisal error, assuming the file
653 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
654 */
655static int ima_bprm_creds_for_exec(struct linux_binprm *bprm)
656{
657 /*
658 * As security_bprm_check() is called multiple times, both
659 * the script and the shebang interpreter are measured, appraised,
660 * and audited. Limit usage of this LSM hook to just measuring,
661 * appraising, and auditing the indirect script execution
662 * (e.g. ./sh example.sh).
663 */
664 if (!bprm->is_check)
665 return 0;
666
667 return ima_bprm_check(bprm);
668}
669
670/**
671 * ima_file_check - based on policy, collect/store measurement.
672 * @file: pointer to the file to be measured
673 * @mask: contains MAY_READ, MAY_WRITE, MAY_EXEC or MAY_APPEND
674 *
675 * Measure files based on the ima_must_measure() policy decision.
676 *
677 * On success return 0. On integrity appraisal error, assuming the file
678 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
679 */
680static int ima_file_check(struct file *file, int mask)
681{
682 struct lsm_prop prop;
683
684 security_current_getlsmprop_subj(&prop);
685 return process_measurement(file, current_cred(), &prop, NULL, 0,
686 mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
687 MAY_APPEND), FILE_CHECK, 0, false);
688}
689
690/*
691 * ima_reset_action_flags - invalidate action flags after a content change
692 * @inode: inode of the file whose content is about to be truncated
693 *
694 * Clear IMA_DONE_MASK so the file is re-collected, re-measured,
695 * re-audited, and re-appraised on next access.
696 */
697static void ima_reset_action_flags(struct inode *inode)
698{
699 struct ima_iint_cache *iint;
700
701 if (!ima_policy_flag || !S_ISREG(inode->i_mode))
702 return;
703
704 iint = ima_iint_find(inode);
705 if (!iint)
706 return;
707
708 mutex_lock(&iint->mutex);
709 iint->flags &= ~IMA_DONE_MASK;
710 iint->measured_pcrs = 0;
711 mutex_unlock(&iint->mutex);
712 return;
713}
714
715static int ima_path_truncate(const struct path *path)
716{
717 ima_reset_action_flags(path->dentry->d_inode);
718 return 0;
719}
720
721static int ima_file_truncate(struct file *file)
722{
723 ima_reset_action_flags(file_inode(file));
724 return 0;
725}
726
727static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf,
728 size_t buf_size)
729{
730 struct ima_iint_cache *iint = NULL, tmp_iint;
731 int rc, hash_algo;
732
733 if (ima_policy_flag) {
734 iint = ima_iint_find(inode);
735 if (iint)
736 mutex_lock(&iint->mutex);
737 }
738
739 if ((!iint || !(iint->flags & IMA_COLLECTED)) && file) {
740 if (iint)
741 mutex_unlock(&iint->mutex);
742
743 memset(&tmp_iint, 0, sizeof(tmp_iint));
744 mutex_init(&tmp_iint.mutex);
745
746 rc = ima_collect_measurement(&tmp_iint, file, NULL, 0,
747 ima_hash_algo, NULL);
748 if (rc < 0) {
749 /* ima_hash could be allocated in case of failure. */
750 if (rc != -ENOMEM)
751 kfree(tmp_iint.ima_hash);
752
753 return -EOPNOTSUPP;
754 }
755
756 iint = &tmp_iint;
757 mutex_lock(&iint->mutex);
758 }
759
760 if (!iint)
761 return -EOPNOTSUPP;
762
763 /*
764 * ima_file_hash can be called when ima_collect_measurement has still
765 * not been called, we might not always have a hash.
766 */
767 if (!iint->ima_hash || !(iint->flags & IMA_COLLECTED)) {
768 mutex_unlock(&iint->mutex);
769 return -EOPNOTSUPP;
770 }
771
772 if (buf) {
773 size_t copied_size;
774
775 copied_size = min_t(size_t, iint->ima_hash->length, buf_size);
776 memcpy(buf, iint->ima_hash->digest, copied_size);
777 }
778 hash_algo = iint->ima_hash->algo;
779 mutex_unlock(&iint->mutex);
780
781 if (iint == &tmp_iint)
782 kfree(iint->ima_hash);
783
784 return hash_algo;
785}
786
787/**
788 * ima_file_hash - return a measurement of the file
789 * @file: pointer to the file
790 * @buf: buffer in which to store the hash
791 * @buf_size: length of the buffer
792 *
793 * On success, return the hash algorithm (as defined in the enum hash_algo).
794 * If buf is not NULL, this function also outputs the hash into buf.
795 * If the hash is larger than buf_size, then only buf_size bytes will be copied.
796 * It generally just makes sense to pass a buffer capable of holding the largest
797 * possible hash: IMA_MAX_DIGEST_SIZE.
798 * The file hash returned is based on the entire file, including the appended
799 * signature.
800 *
801 * If the measurement cannot be performed, return -EOPNOTSUPP.
802 * If the parameters are incorrect, return -EINVAL.
803 */
804int ima_file_hash(struct file *file, char *buf, size_t buf_size)
805{
806 if (!file)
807 return -EINVAL;
808
809 return __ima_inode_hash(file_inode(file), file, buf, buf_size);
810}
811EXPORT_SYMBOL_GPL(ima_file_hash);
812
813/**
814 * ima_inode_hash - return the stored measurement if the inode has been hashed
815 * and is in the iint cache.
816 * @inode: pointer to the inode
817 * @buf: buffer in which to store the hash
818 * @buf_size: length of the buffer
819 *
820 * On success, return the hash algorithm (as defined in the enum hash_algo).
821 * If buf is not NULL, this function also outputs the hash into buf.
822 * If the hash is larger than buf_size, then only buf_size bytes will be copied.
823 * It generally just makes sense to pass a buffer capable of holding the largest
824 * possible hash: IMA_MAX_DIGEST_SIZE.
825 * The hash returned is based on the entire contents, including the appended
826 * signature.
827 *
828 * If IMA is disabled or if no measurement is available, return -EOPNOTSUPP.
829 * If the parameters are incorrect, return -EINVAL.
830 */
831int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size)
832{
833 if (!inode)
834 return -EINVAL;
835
836 return __ima_inode_hash(inode, NULL, buf, buf_size);
837}
838EXPORT_SYMBOL_GPL(ima_inode_hash);
839
840/**
841 * ima_post_create_tmpfile - mark newly created tmpfile as new
842 * @idmap: idmap of the mount the inode was found from
843 * @inode: inode of the newly created tmpfile
844 *
845 * No measuring, appraising or auditing of newly created tmpfiles is needed.
846 * Skip calling process_measurement(), but indicate which newly, created
847 * tmpfiles are in policy.
848 */
849static void ima_post_create_tmpfile(const struct mnt_idmap *idmap,
850 struct inode *inode)
851
852{
853 struct ima_iint_cache *iint;
854 int must_appraise;
855
856 if (!ima_policy_flag || !S_ISREG(inode->i_mode))
857 return;
858
859 must_appraise = ima_must_appraise(idmap, inode, MAY_ACCESS,
860 FILE_CHECK);
861 if (!must_appraise)
862 return;
863
864 /* Nothing to do if we can't allocate memory */
865 iint = ima_inode_get(inode);
866 if (!iint)
867 return;
868
869 /* needed for writing the security xattrs */
870 set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
871 iint->ima_file_status = INTEGRITY_PASS;
872}
873
874/**
875 * ima_post_path_mknod - mark as a new inode
876 * @idmap: idmap of the mount the inode was found from
877 * @dentry: newly created dentry
878 *
879 * Mark files created via the mknodat syscall as new, so that the
880 * file data can be written later.
881 */
882static void ima_post_path_mknod(const struct mnt_idmap *idmap, struct dentry *dentry)
883{
884 struct ima_iint_cache *iint;
885 struct inode *inode = dentry->d_inode;
886 int must_appraise;
887
888 if (!ima_policy_flag || !S_ISREG(inode->i_mode))
889 return;
890
891 must_appraise = ima_must_appraise(idmap, inode, MAY_ACCESS,
892 FILE_CHECK);
893 if (!must_appraise)
894 return;
895
896 /* Nothing to do if we can't allocate memory */
897 iint = ima_inode_get(inode);
898 if (!iint)
899 return;
900
901 /* needed for re-opening empty files */
902 iint->flags |= IMA_NEW_FILE;
903}
904
905/**
906 * ima_read_file - pre-measure/appraise hook decision based on policy
907 * @file: pointer to the file to be measured/appraised/audit
908 * @read_id: caller identifier
909 * @contents: whether a subsequent call will be made to ima_post_read_file()
910 *
911 * Permit reading a file based on policy. The policy rules are written
912 * in terms of the policy identifier. Appraising the integrity of
913 * a file requires a file descriptor.
914 *
915 * For permission return 0, otherwise return -EACCES.
916 */
917static int ima_read_file(struct file *file, enum kernel_read_file_id read_id,
918 bool contents)
919{
920 enum ima_hooks func;
921 struct lsm_prop prop;
922
923 /*
924 * Do devices using pre-allocated memory run the risk of the
925 * firmware being accessible to the device prior to the completion
926 * of IMA's signature verification any more than when using two
927 * buffers? It may be desirable to include the buffer address
928 * in this API and walk all the dma_map_single() mappings to check.
929 */
930
931 /*
932 * There will be a call made to ima_post_read_file() with
933 * a filled buffer, so we don't need to perform an extra
934 * read early here.
935 */
936 if (contents)
937 return 0;
938
939 /* Read entire file for all partial reads. */
940 func = read_idmap[read_id] ?: FILE_CHECK;
941 security_current_getlsmprop_subj(&prop);
942 return process_measurement(file, current_cred(), &prop, NULL, 0,
943 MAY_READ, func, 0, false);
944}
945
946const int read_idmap[READING_MAX_ID] = {
947 [READING_FIRMWARE] = FIRMWARE_CHECK,
948 [READING_MODULE] = MODULE_CHECK,
949 [READING_MODULE_COMPRESSED] = MODULE_CHECK,
950 [READING_KEXEC_IMAGE] = KEXEC_KERNEL_CHECK,
951 [READING_KEXEC_INITRAMFS] = KEXEC_INITRAMFS_CHECK,
952 [READING_POLICY] = POLICY_CHECK
953};
954
955/**
956 * ima_post_read_file - in memory collect/appraise/audit measurement
957 * @file: pointer to the file to be measured/appraised/audit
958 * @buf: pointer to in memory file contents
959 * @size: size of in memory file contents
960 * @read_id: caller identifier
961 *
962 * Measure/appraise/audit in memory file based on policy. Policy rules
963 * are written in terms of a policy identifier.
964 *
965 * On success return 0. On integrity appraisal error, assuming the file
966 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
967 */
968static int ima_post_read_file(struct file *file, char *buf, loff_t size,
969 enum kernel_read_file_id read_id)
970{
971 enum ima_hooks func;
972 struct lsm_prop prop;
973
974 /* permit signed certs */
975 if (!file && read_id == READING_X509_CERTIFICATE)
976 return 0;
977
978 if (!file || !buf || size == 0) { /* should never happen */
979 if (ima_appraise & IMA_APPRAISE_ENFORCE)
980 return -EACCES;
981 return 0;
982 }
983
984 func = read_idmap[read_id] ?: FILE_CHECK;
985 security_current_getlsmprop_subj(&prop);
986 return process_measurement(file, current_cred(), &prop, buf, size,
987 MAY_READ, func, read_id, false);
988}
989
990/**
991 * ima_load_data - appraise decision based on policy
992 * @id: kernel load data caller identifier
993 * @contents: whether the full contents will be available in a later
994 * call to ima_post_load_data().
995 *
996 * Callers of this LSM hook can not measure, appraise, or audit the
997 * data provided by userspace. Enforce policy rules requiring a file
998 * signature (eg. kexec'ed kernel image).
999 *
1000 * For permission return 0, otherwise return -EACCES.
1001 */
1002static int ima_load_data(enum kernel_load_data_id id, bool contents)
1003{
1004 bool ima_enforce, sig_enforce;
1005
1006 ima_enforce =
1007 (ima_appraise & IMA_APPRAISE_ENFORCE) == IMA_APPRAISE_ENFORCE;
1008
1009 switch (id) {
1010 case LOADING_KEXEC_IMAGE:
1011 if (IS_ENABLED(CONFIG_KEXEC_SIG) && arch_get_secureboot()) {
1012 pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load syscall.\n");
1013 return -EACCES;
1014 }
1015
1016 if (ima_enforce && (ima_appraise & IMA_APPRAISE_KEXEC)) {
1017 pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load syscall.\n");
1018 return -EACCES; /* INTEGRITY_UNKNOWN */
1019 }
1020 break;
1021 case LOADING_FIRMWARE:
1022 if (ima_enforce && (ima_appraise & IMA_APPRAISE_FIRMWARE) && !contents) {
1023 pr_err("Prevent firmware sysfs fallback loading.\n");
1024 return -EACCES; /* INTEGRITY_UNKNOWN */
1025 }
1026 break;
1027 case LOADING_MODULE:
1028 sig_enforce = is_module_sig_enforced();
1029
1030 if (ima_enforce && (!sig_enforce
1031 && (ima_appraise & IMA_APPRAISE_MODULES))) {
1032 pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter might help\n");
1033 return -EACCES; /* INTEGRITY_UNKNOWN */
1034 }
1035 break;
1036 default:
1037 break;
1038 }
1039 return 0;
1040}
1041
1042/**
1043 * ima_post_load_data - appraise decision based on policy
1044 * @buf: pointer to in memory file contents
1045 * @size: size of in memory file contents
1046 * @load_id: kernel load data caller identifier
1047 * @description: @load_id-specific description of contents
1048 *
1049 * Measure/appraise/audit in memory buffer based on policy. Policy rules
1050 * are written in terms of a policy identifier.
1051 *
1052 * On success return 0. On integrity appraisal error, assuming the file
1053 * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
1054 */
1055static int ima_post_load_data(char *buf, loff_t size,
1056 enum kernel_load_data_id load_id,
1057 char *description)
1058{
1059 if (load_id == LOADING_FIRMWARE) {
1060 if ((ima_appraise & IMA_APPRAISE_FIRMWARE) &&
1061 (ima_appraise & IMA_APPRAISE_ENFORCE)) {
1062 pr_err("Prevent firmware loading_store.\n");
1063 return -EACCES; /* INTEGRITY_UNKNOWN */
1064 }
1065 return 0;
1066 }
1067
1068 /*
1069 * Measure the init_module syscall buffer containing the ELF image.
1070 */
1071 if (load_id == LOADING_MODULE)
1072 ima_measure_critical_data("modules", "init_module",
1073 buf, size, true, NULL, 0);
1074
1075 return 0;
1076}
1077
1078/**
1079 * process_buffer_measurement - Measure the buffer or the buffer data hash
1080 * @idmap: idmap of the mount the inode was found from
1081 * @inode: inode associated with the object being measured (NULL for KEY_CHECK)
1082 * @buf: pointer to the buffer that needs to be added to the log.
1083 * @size: size of buffer(in bytes).
1084 * @eventname: event name to be used for the buffer entry.
1085 * @func: IMA hook
1086 * @pcr: pcr to extend the measurement
1087 * @func_data: func specific data, may be NULL
1088 * @buf_hash: measure buffer data hash
1089 * @digest: buffer digest will be written to
1090 * @digest_len: buffer length
1091 *
1092 * Based on policy, either the buffer data or buffer data hash is measured
1093 *
1094 * Return: 0 if the buffer has been successfully measured, 1 if the digest
1095 * has been written to the passed location but not added to a measurement entry,
1096 * a negative value otherwise.
1097 */
1098int process_buffer_measurement(const struct mnt_idmap *idmap,
1099 struct inode *inode, const void *buf, int size,
1100 const char *eventname, enum ima_hooks func,
1101 int pcr, const char *func_data,
1102 bool buf_hash, u8 *digest, size_t digest_len)
1103{
1104 int ret = 0;
1105 const char *audit_cause = "ENOMEM";
1106 struct ima_template_entry *entry = NULL;
1107 struct ima_iint_cache iint = {};
1108 struct ima_event_data event_data = {.iint = &iint,
1109 .filename = eventname,
1110 .buf = buf,
1111 .buf_len = size};
1112 struct ima_template_desc *template;
1113 struct ima_max_digest_data hash;
1114 struct ima_digest_data *hash_hdr = container_of(&hash.hdr,
1115 struct ima_digest_data, hdr);
1116 char digest_hash[IMA_MAX_DIGEST_SIZE];
1117 int digest_hash_len = hash_digest_size[ima_hash_algo];
1118 int violation = 0;
1119 int action = 0;
1120 struct lsm_prop prop;
1121
1122 if (digest && digest_len < digest_hash_len)
1123 return -EINVAL;
1124
1125 if (!ima_policy_flag && !digest)
1126 return -ENOENT;
1127
1128 template = ima_template_desc_buf();
1129 if (!template) {
1130 ret = -EINVAL;
1131 audit_cause = "ima_template_desc_buf";
1132 goto out;
1133 }
1134
1135 /*
1136 * Both LSM hooks and auxiliary based buffer measurements are
1137 * based on policy. To avoid code duplication, differentiate
1138 * between the LSM hooks and auxiliary buffer measurements,
1139 * retrieving the policy rule information only for the LSM hook
1140 * buffer measurements.
1141 */
1142 if (func) {
1143 security_current_getlsmprop_subj(&prop);
1144 action = ima_get_action(idmap, inode, current_cred(),
1145 &prop, 0, func, &pcr, &template,
1146 func_data, NULL);
1147 if (!(action & IMA_MEASURE) && !digest)
1148 return -ENOENT;
1149 }
1150
1151 if (!pcr)
1152 pcr = CONFIG_IMA_MEASURE_PCR_IDX;
1153
1154 iint.ima_hash = hash_hdr;
1155 iint.ima_hash->algo = ima_hash_algo;
1156 iint.ima_hash->length = hash_digest_size[ima_hash_algo];
1157
1158 ret = ima_calc_buffer_hash(buf, size, iint.ima_hash);
1159 if (ret < 0) {
1160 audit_cause = "hashing_error";
1161 goto out;
1162 }
1163
1164 if (buf_hash) {
1165 memcpy(digest_hash, hash_hdr->digest, digest_hash_len);
1166
1167 ret = ima_calc_buffer_hash(digest_hash, digest_hash_len,
1168 iint.ima_hash);
1169 if (ret < 0) {
1170 audit_cause = "hashing_error";
1171 goto out;
1172 }
1173
1174 event_data.buf = digest_hash;
1175 event_data.buf_len = digest_hash_len;
1176 }
1177
1178 if (digest)
1179 memcpy(digest, iint.ima_hash->digest, digest_hash_len);
1180
1181 if (!ima_policy_flag || (func && !(action & IMA_MEASURE)))
1182 return 1;
1183
1184 ret = ima_alloc_init_template(&event_data, &entry, template);
1185 if (ret < 0) {
1186 audit_cause = "alloc_entry";
1187 goto out;
1188 }
1189
1190 ret = ima_store_template(entry, violation, NULL, event_data.buf, pcr);
1191 if (ret < 0) {
1192 audit_cause = "store_entry";
1193 ima_free_template_entry(entry);
1194 }
1195
1196out:
1197 if (ret < 0)
1198 integrity_audit_message(AUDIT_INTEGRITY_PCR, NULL, eventname,
1199 func_measure_str(func),
1200 audit_cause, ret, 0, ret);
1201
1202 return ret;
1203}
1204
1205/**
1206 * ima_kexec_cmdline - measure kexec cmdline boot args
1207 * @kernel_fd: file descriptor of the kexec kernel being loaded
1208 * @buf: pointer to buffer
1209 * @size: size of buffer
1210 *
1211 * Buffers can only be measured, not appraised.
1212 */
1213void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
1214{
1215 if (!buf || !size)
1216 return;
1217
1218 CLASS(fd, f)(kernel_fd);
1219 if (fd_empty(f))
1220 return;
1221
1222 process_buffer_measurement(file_mnt_idmap(fd_file(f)), file_inode(fd_file(f)),
1223 buf, size, "kexec-cmdline", KEXEC_CMDLINE, 0,
1224 NULL, false, NULL, 0);
1225}
1226
1227/**
1228 * ima_measure_critical_data - measure kernel integrity critical data
1229 * @event_label: unique event label for grouping and limiting critical data
1230 * @event_name: event name for the record in the IMA measurement list
1231 * @buf: pointer to buffer data
1232 * @buf_len: length of buffer data (in bytes)
1233 * @hash: measure buffer data hash
1234 * @digest: buffer digest will be written to
1235 * @digest_len: buffer length
1236 *
1237 * Measure data critical to the integrity of the kernel into the IMA log
1238 * and extend the pcr. Examples of critical data could be various data
1239 * structures, policies, and states stored in kernel memory that can
1240 * impact the integrity of the system.
1241 *
1242 * Return: 0 if the buffer has been successfully measured, 1 if the digest
1243 * has been written to the passed location but not added to a measurement entry,
1244 * a negative value otherwise.
1245 */
1246int ima_measure_critical_data(const char *event_label,
1247 const char *event_name,
1248 const void *buf, size_t buf_len,
1249 bool hash, u8 *digest, size_t digest_len)
1250{
1251 if (!event_name || !event_label || !buf || !buf_len)
1252 return -ENOPARAM;
1253
1254 return process_buffer_measurement(&nop_mnt_idmap, NULL, buf, buf_len,
1255 event_name, CRITICAL_DATA, 0,
1256 event_label, hash, digest,
1257 digest_len);
1258}
1259EXPORT_SYMBOL_GPL(ima_measure_critical_data);
1260
1261/**
1262 * ima_measure_raw_policy - Measure the raw policy write buffer
1263 * @buf: pointer to the buffer containing the raw policy data
1264 * @buf_len: size of the buffer
1265 *
1266 * Measure the raw policy buffer sent to the IMA policy securityfs file. The
1267 * buffer is written from userspace, and the measurement is performed before
1268 * parsing it. This measurement includes any data written on the policy file
1269 * such as malformed policy rules and comments.
1270 *
1271 * Return 0 on success, a negative value otherwise.
1272 */
1273int ima_measure_raw_policy(const char *buf, size_t buf_len)
1274{
1275 if (!buf || !buf_len)
1276 return -EINVAL;
1277
1278 return process_buffer_measurement(&nop_mnt_idmap, NULL, buf, buf_len,
1279 "ima_policy_written", POLICY_CHECK,
1280 0, NULL, false, NULL, 0);
1281}
1282
1283#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
1284
1285/**
1286 * ima_kernel_module_request - Prevent crypto-pkcs1(rsa,*) requests
1287 * @kmod_name: kernel module name
1288 *
1289 * Avoid a verification loop where verifying the signature of the modprobe
1290 * binary requires executing modprobe itself. Since the modprobe iint->mutex
1291 * is already held when the signature verification is performed, a deadlock
1292 * occurs as soon as modprobe is executed within the critical region, since
1293 * the same lock cannot be taken again.
1294 *
1295 * This happens when public_key_verify_signature(), in case of RSA algorithm,
1296 * use alg_name to store internal information in order to construct an
1297 * algorithm on the fly, but crypto_larval_lookup() will try to use alg_name
1298 * in order to load a kernel module with same name.
1299 *
1300 * Since we don't have any real "crypto-pkcs1(rsa,*)" kernel modules,
1301 * we are safe to fail such module request from crypto_larval_lookup(), and
1302 * avoid the verification loop.
1303 *
1304 * Return: Zero if it is safe to load the kernel module, -EINVAL otherwise.
1305 */
1306static int ima_kernel_module_request(char *kmod_name)
1307{
1308 if (strncmp(kmod_name, "crypto-pkcs1(rsa,", 17) == 0)
1309 return -EINVAL;
1310
1311 return 0;
1312}
1313
1314#endif /* CONFIG_INTEGRITY_ASYMMETRIC_KEYS */
1315
1316static int __init init_ima(void)
1317{
1318 int error;
1319
1320 /*Note that turning IMA off is intentionally limited to kdump kernel.*/
1321 if (ima_disabled && is_kdump_kernel()) {
1322 pr_info("IMA functionality is disabled");
1323 return 0;
1324 }
1325
1326 ima_appraise_parse_cmdline();
1327 ima_init_template_list();
1328 hash_setup(CONFIG_IMA_DEFAULT_HASH);
1329 error = ima_init();
1330
1331 if (error && strcmp(hash_algo_name[ima_hash_algo],
1332 CONFIG_IMA_DEFAULT_HASH) != 0) {
1333 pr_info("Allocating %s failed, going to use default hash algorithm %s\n",
1334 hash_algo_name[ima_hash_algo], CONFIG_IMA_DEFAULT_HASH);
1335 hash_setup_done = 0;
1336 hash_setup(CONFIG_IMA_DEFAULT_HASH);
1337 error = ima_init();
1338 }
1339
1340 if (error)
1341 return error;
1342
1343 error = register_blocking_lsm_notifier(&ima_lsm_policy_notifier);
1344 if (error)
1345 pr_warn("Couldn't register LSM notifier, error %d\n", error);
1346
1347 if (!error)
1348 ima_update_policy_flags();
1349
1350 return error;
1351}
1352
1353static struct security_hook_list ima_hooks[] __ro_after_init = {
1354 LSM_HOOK_INIT(bprm_check_security, ima_bprm_check),
1355 LSM_HOOK_INIT(bprm_creds_for_exec, ima_bprm_creds_for_exec),
1356 LSM_HOOK_INIT(bprm_creds_from_file, ima_creds_check),
1357 LSM_HOOK_INIT(file_post_open, ima_file_check),
1358 LSM_HOOK_INIT(inode_post_create_tmpfile, ima_post_create_tmpfile),
1359 LSM_HOOK_INIT(file_release, ima_file_free),
1360 LSM_HOOK_INIT(mmap_file, ima_file_mmap),
1361 LSM_HOOK_INIT(file_mprotect, ima_file_mprotect),
1362 LSM_HOOK_INIT(file_truncate, ima_file_truncate),
1363 LSM_HOOK_INIT(kernel_load_data, ima_load_data),
1364 LSM_HOOK_INIT(kernel_post_load_data, ima_post_load_data),
1365 LSM_HOOK_INIT(kernel_read_file, ima_read_file),
1366 LSM_HOOK_INIT(kernel_post_read_file, ima_post_read_file),
1367 LSM_HOOK_INIT(path_post_mknod, ima_post_path_mknod),
1368 LSM_HOOK_INIT(path_truncate, ima_path_truncate),
1369#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
1370 LSM_HOOK_INIT(key_post_create_or_update, ima_post_key_create_or_update),
1371#endif
1372#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
1373 LSM_HOOK_INIT(kernel_module_request, ima_kernel_module_request),
1374#endif
1375 LSM_HOOK_INIT(inode_free_security_rcu, ima_inode_free_rcu),
1376};
1377
1378static const struct lsm_id ima_lsmid = {
1379 .name = "ima",
1380 .id = LSM_ID_IMA,
1381};
1382
1383static int __init init_ima_lsm(void)
1384{
1385 ima_iintcache_init();
1386 security_add_hooks(ima_hooks, ARRAY_SIZE(ima_hooks), &ima_lsmid);
1387 init_ima_appraise_lsm(&ima_lsmid);
1388 return 0;
1389}
1390
1391struct lsm_blob_sizes ima_blob_sizes __ro_after_init = {
1392 .lbs_inode = sizeof(struct ima_iint_cache *),
1393};
1394
1395DEFINE_LSM(ima) = {
1396 .id = &ima_lsmid,
1397 .init = init_ima_lsm,
1398 .order = LSM_ORDER_LAST,
1399 .blobs = &ima_blob_sizes,
1400 /* Start IMA after the TPM is available */
1401#ifndef CONFIG_IMA_INIT_LATE_SYNC
1402 .initcall_late = init_ima,
1403#else
1404 .initcall_late_sync = init_ima,
1405#endif
1406};