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

source code of linux/security/integrity/ima/ima_main.c