xref: /linux/security/integrity/ima/ima_main.c (revision 3fd6c59042dbba50391e30862beac979491145fe)
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 
31 #include "ima.h"
32 
33 #ifdef CONFIG_IMA_APPRAISE
34 int ima_appraise = IMA_APPRAISE_ENFORCE;
35 #else
36 int ima_appraise;
37 #endif
38 
39 int __ro_after_init ima_hash_algo = HASH_ALGO_SHA1;
40 static int hash_setup_done;
41 
42 static struct notifier_block ima_lsm_policy_notifier = {
43 	.notifier_call = ima_lsm_policy_change,
44 };
45 
hash_setup(char * str)46 static int __init hash_setup(char *str)
47 {
48 	struct ima_template_desc *template_desc = ima_template_desc_current();
49 	int i;
50 
51 	if (hash_setup_done)
52 		return 1;
53 
54 	if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
55 		if (strncmp(str, "sha1", 4) == 0) {
56 			ima_hash_algo = HASH_ALGO_SHA1;
57 		} else if (strncmp(str, "md5", 3) == 0) {
58 			ima_hash_algo = HASH_ALGO_MD5;
59 		} else {
60 			pr_err("invalid hash algorithm \"%s\" for template \"%s\"",
61 				str, IMA_TEMPLATE_IMA_NAME);
62 			return 1;
63 		}
64 		goto out;
65 	}
66 
67 	i = match_string(hash_algo_name, HASH_ALGO__LAST, str);
68 	if (i < 0) {
69 		pr_err("invalid hash algorithm \"%s\"", str);
70 		return 1;
71 	}
72 
73 	ima_hash_algo = i;
74 out:
75 	hash_setup_done = 1;
76 	return 1;
77 }
78 __setup("ima_hash=", hash_setup);
79 
ima_get_current_hash_algo(void)80 enum hash_algo ima_get_current_hash_algo(void)
81 {
82 	return ima_hash_algo;
83 }
84 
85 /* Prevent mmap'ing a file execute that is already mmap'ed write */
mmap_violation_check(enum ima_hooks func,struct file * file,char ** pathbuf,const char ** pathname,char * filename)86 static int mmap_violation_check(enum ima_hooks func, struct file *file,
87 				char **pathbuf, const char **pathname,
88 				char *filename)
89 {
90 	struct inode *inode;
91 	int rc = 0;
92 
93 	if ((func == MMAP_CHECK || func == MMAP_CHECK_REQPROT) &&
94 	    mapping_writably_mapped(file->f_mapping)) {
95 		rc = -ETXTBSY;
96 		inode = file_inode(file);
97 
98 		if (!*pathbuf)	/* ima_rdwr_violation possibly pre-fetched */
99 			*pathname = ima_d_path(&file->f_path, pathbuf,
100 					       filename);
101 		integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, *pathname,
102 				    "mmap_file", "mmapped_writers", rc, 0);
103 	}
104 	return rc;
105 }
106 
107 /*
108  * ima_rdwr_violation_check
109  *
110  * Only invalidate the PCR for measured files:
111  *	- Opening a file for write when already open for read,
112  *	  results in a time of measure, time of use (ToMToU) error.
113  *	- Opening a file for read when already open for write,
114  *	  could result in a file measurement error.
115  *
116  */
ima_rdwr_violation_check(struct file * file,struct ima_iint_cache * iint,int must_measure,char ** pathbuf,const char ** pathname,char * filename)117 static void ima_rdwr_violation_check(struct file *file,
118 				     struct ima_iint_cache *iint,
119 				     int must_measure,
120 				     char **pathbuf,
121 				     const char **pathname,
122 				     char *filename)
123 {
124 	struct inode *inode = file_inode(file);
125 	fmode_t mode = file->f_mode;
126 	bool send_tomtou = false, send_writers = false;
127 
128 	if (mode & FMODE_WRITE) {
129 		if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) {
130 			if (!iint)
131 				iint = ima_iint_find(inode);
132 			/* IMA_MEASURE is set from reader side */
133 			if (iint && test_bit(IMA_MUST_MEASURE,
134 						&iint->atomic_flags))
135 				send_tomtou = true;
136 		}
137 	} else {
138 		if (must_measure)
139 			set_bit(IMA_MUST_MEASURE, &iint->atomic_flags);
140 		if (inode_is_open_for_write(inode) && must_measure)
141 			send_writers = true;
142 	}
143 
144 	if (!send_tomtou && !send_writers)
145 		return;
146 
147 	*pathname = ima_d_path(&file->f_path, pathbuf, filename);
148 
149 	if (send_tomtou)
150 		ima_add_violation(file, *pathname, iint,
151 				  "invalid_pcr", "ToMToU");
152 	if (send_writers)
153 		ima_add_violation(file, *pathname, iint,
154 				  "invalid_pcr", "open_writers");
155 }
156 
ima_check_last_writer(struct ima_iint_cache * iint,struct inode * inode,struct file * file)157 static void ima_check_last_writer(struct ima_iint_cache *iint,
158 				  struct inode *inode, struct file *file)
159 {
160 	fmode_t mode = file->f_mode;
161 	bool update;
162 
163 	if (!(mode & FMODE_WRITE))
164 		return;
165 
166 	mutex_lock(&iint->mutex);
167 	if (atomic_read(&inode->i_writecount) == 1) {
168 		struct kstat stat;
169 
170 		update = test_and_clear_bit(IMA_UPDATE_XATTR,
171 					    &iint->atomic_flags);
172 		if ((iint->flags & IMA_NEW_FILE) ||
173 		    vfs_getattr_nosec(&file->f_path, &stat,
174 				      STATX_CHANGE_COOKIE,
175 				      AT_STATX_SYNC_AS_STAT) ||
176 		    !(stat.result_mask & STATX_CHANGE_COOKIE) ||
177 		    stat.change_cookie != iint->real_inode.version) {
178 			iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
179 			iint->measured_pcrs = 0;
180 			if (update)
181 				ima_update_xattr(iint, file);
182 		}
183 	}
184 	mutex_unlock(&iint->mutex);
185 }
186 
187 /**
188  * ima_file_free - called on __fput()
189  * @file: pointer to file structure being freed
190  *
191  * Flag files that changed, based on i_version
192  */
ima_file_free(struct file * file)193 static void ima_file_free(struct file *file)
194 {
195 	struct inode *inode = file_inode(file);
196 	struct ima_iint_cache *iint;
197 
198 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
199 		return;
200 
201 	iint = ima_iint_find(inode);
202 	if (!iint)
203 		return;
204 
205 	ima_check_last_writer(iint, inode, file);
206 }
207 
process_measurement(struct file * file,const struct cred * cred,struct lsm_prop * prop,char * buf,loff_t size,int mask,enum ima_hooks func)208 static int process_measurement(struct file *file, const struct cred *cred,
209 			       struct lsm_prop *prop, char *buf, loff_t size,
210 			       int mask, enum ima_hooks func)
211 {
212 	struct inode *real_inode, *inode = file_inode(file);
213 	struct ima_iint_cache *iint = NULL;
214 	struct ima_template_desc *template_desc = NULL;
215 	struct inode *metadata_inode;
216 	char *pathbuf = NULL;
217 	char filename[NAME_MAX];
218 	const char *pathname = NULL;
219 	int rc = 0, action, must_appraise = 0;
220 	int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
221 	struct evm_ima_xattr_data *xattr_value = NULL;
222 	struct modsig *modsig = NULL;
223 	int xattr_len = 0;
224 	bool violation_check;
225 	enum hash_algo hash_algo;
226 	unsigned int allowed_algos = 0;
227 
228 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
229 		return 0;
230 
231 	/* Return an IMA_MEASURE, IMA_APPRAISE, IMA_AUDIT action
232 	 * bitmask based on the appraise/audit/measurement policy.
233 	 * Included is the appraise submask.
234 	 */
235 	action = ima_get_action(file_mnt_idmap(file), inode, cred, prop,
236 				mask, func, &pcr, &template_desc, NULL,
237 				&allowed_algos);
238 	violation_check = ((func == FILE_CHECK || func == MMAP_CHECK ||
239 			    func == MMAP_CHECK_REQPROT) &&
240 			   (ima_policy_flag & IMA_MEASURE));
241 	if (!action && !violation_check)
242 		return 0;
243 
244 	must_appraise = action & IMA_APPRAISE;
245 
246 	/*  Is the appraise rule hook specific?  */
247 	if (action & IMA_FILE_APPRAISE)
248 		func = FILE_CHECK;
249 
250 	inode_lock(inode);
251 
252 	if (action) {
253 		iint = ima_inode_get(inode);
254 		if (!iint)
255 			rc = -ENOMEM;
256 	}
257 
258 	if (!rc && violation_check)
259 		ima_rdwr_violation_check(file, iint, action & IMA_MEASURE,
260 					 &pathbuf, &pathname, filename);
261 
262 	inode_unlock(inode);
263 
264 	if (rc)
265 		goto out;
266 	if (!action)
267 		goto out;
268 
269 	mutex_lock(&iint->mutex);
270 
271 	if (test_and_clear_bit(IMA_CHANGE_ATTR, &iint->atomic_flags))
272 		/* reset appraisal flags if ima_inode_post_setattr was called */
273 		iint->flags &= ~(IMA_APPRAISE | IMA_APPRAISED |
274 				 IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK |
275 				 IMA_NONACTION_FLAGS);
276 
277 	/*
278 	 * Re-evaulate the file if either the xattr has changed or the
279 	 * kernel has no way of detecting file change on the filesystem.
280 	 * (Limited to privileged mounted filesystems.)
281 	 */
282 	if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags) ||
283 	    ((inode->i_sb->s_iflags & SB_I_IMA_UNVERIFIABLE_SIGNATURE) &&
284 	     !(inode->i_sb->s_iflags & SB_I_UNTRUSTED_MOUNTER) &&
285 	     !(action & IMA_FAIL_UNVERIFIABLE_SIGS))) {
286 		iint->flags &= ~IMA_DONE_MASK;
287 		iint->measured_pcrs = 0;
288 	}
289 
290 	/*
291 	 * On stacked filesystems, detect and re-evaluate file data and
292 	 * metadata changes.
293 	 */
294 	real_inode = d_real_inode(file_dentry(file));
295 	if (real_inode != inode &&
296 	    (action & IMA_DO_MASK) && (iint->flags & IMA_DONE_MASK)) {
297 		if (!IS_I_VERSION(real_inode) ||
298 		    integrity_inode_attrs_changed(&iint->real_inode,
299 						  real_inode)) {
300 			iint->flags &= ~IMA_DONE_MASK;
301 			iint->measured_pcrs = 0;
302 		}
303 
304 		/*
305 		 * Reset the EVM status when metadata changed.
306 		 */
307 		metadata_inode = d_inode(d_real(file_dentry(file),
308 					 D_REAL_METADATA));
309 		if (evm_metadata_changed(inode, metadata_inode))
310 			iint->flags &= ~(IMA_APPRAISED |
311 					 IMA_APPRAISED_SUBMASK);
312 	}
313 
314 	/* Determine if already appraised/measured based on bitmask
315 	 * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED,
316 	 *  IMA_AUDIT, IMA_AUDITED)
317 	 */
318 	iint->flags |= action;
319 	action &= IMA_DO_MASK;
320 	action &= ~((iint->flags & (IMA_DONE_MASK ^ IMA_MEASURED)) >> 1);
321 
322 	/* If target pcr is already measured, unset IMA_MEASURE action */
323 	if ((action & IMA_MEASURE) && (iint->measured_pcrs & (0x1 << pcr)))
324 		action ^= IMA_MEASURE;
325 
326 	/* HASH sets the digital signature and update flags, nothing else */
327 	if ((action & IMA_HASH) &&
328 	    !(test_bit(IMA_DIGSIG, &iint->atomic_flags))) {
329 		xattr_len = ima_read_xattr(file_dentry(file),
330 					   &xattr_value, xattr_len);
331 		if ((xattr_value && xattr_len > 2) &&
332 		    (xattr_value->type == EVM_IMA_XATTR_DIGSIG))
333 			set_bit(IMA_DIGSIG, &iint->atomic_flags);
334 		iint->flags |= IMA_HASHED;
335 		action ^= IMA_HASH;
336 		set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
337 	}
338 
339 	/* Nothing to do, just return existing appraised status */
340 	if (!action) {
341 		if (must_appraise) {
342 			rc = mmap_violation_check(func, file, &pathbuf,
343 						  &pathname, filename);
344 			if (!rc)
345 				rc = ima_get_cache_status(iint, func);
346 		}
347 		goto out_locked;
348 	}
349 
350 	if ((action & IMA_APPRAISE_SUBMASK) ||
351 	    strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0) {
352 		/* read 'security.ima' */
353 		xattr_len = ima_read_xattr(file_dentry(file),
354 					   &xattr_value, xattr_len);
355 
356 		/*
357 		 * Read the appended modsig if allowed by the policy, and allow
358 		 * an additional measurement list entry, if needed, based on the
359 		 * template format and whether the file was already measured.
360 		 */
361 		if (iint->flags & IMA_MODSIG_ALLOWED) {
362 			rc = ima_read_modsig(func, buf, size, &modsig);
363 
364 			if (!rc && ima_template_has_modsig(template_desc) &&
365 			    iint->flags & IMA_MEASURED)
366 				action |= IMA_MEASURE;
367 		}
368 	}
369 
370 	hash_algo = ima_get_hash_algo(xattr_value, xattr_len);
371 
372 	rc = ima_collect_measurement(iint, file, buf, size, hash_algo, modsig);
373 	if (rc != 0 && rc != -EBADF && rc != -EINVAL)
374 		goto out_locked;
375 
376 	if (!pathbuf)	/* ima_rdwr_violation possibly pre-fetched */
377 		pathname = ima_d_path(&file->f_path, &pathbuf, filename);
378 
379 	if (action & IMA_MEASURE)
380 		ima_store_measurement(iint, file, pathname,
381 				      xattr_value, xattr_len, modsig, pcr,
382 				      template_desc);
383 	if (rc == 0 && (action & IMA_APPRAISE_SUBMASK)) {
384 		rc = ima_check_blacklist(iint, modsig, pcr);
385 		if (rc != -EPERM) {
386 			inode_lock(inode);
387 			rc = ima_appraise_measurement(func, iint, file,
388 						      pathname, xattr_value,
389 						      xattr_len, modsig);
390 			inode_unlock(inode);
391 		}
392 		if (!rc)
393 			rc = mmap_violation_check(func, file, &pathbuf,
394 						  &pathname, filename);
395 	}
396 	if (action & IMA_AUDIT)
397 		ima_audit_measurement(iint, pathname);
398 
399 	if ((file->f_flags & O_DIRECT) && (iint->flags & IMA_PERMIT_DIRECTIO))
400 		rc = 0;
401 
402 	/* Ensure the digest was generated using an allowed algorithm */
403 	if (rc == 0 && must_appraise && allowed_algos != 0 &&
404 	    (allowed_algos & (1U << hash_algo)) == 0) {
405 		rc = -EACCES;
406 
407 		integrity_audit_msg(AUDIT_INTEGRITY_DATA, file_inode(file),
408 				    pathname, "collect_data",
409 				    "denied-hash-algorithm", rc, 0);
410 	}
411 out_locked:
412 	if ((mask & MAY_WRITE) && test_bit(IMA_DIGSIG, &iint->atomic_flags) &&
413 	     !(iint->flags & IMA_NEW_FILE))
414 		rc = -EACCES;
415 	mutex_unlock(&iint->mutex);
416 	kfree(xattr_value);
417 	ima_free_modsig(modsig);
418 out:
419 	if (pathbuf)
420 		__putname(pathbuf);
421 	if (must_appraise) {
422 		if (rc && (ima_appraise & IMA_APPRAISE_ENFORCE))
423 			return -EACCES;
424 		if (file->f_mode & FMODE_WRITE)
425 			set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
426 	}
427 	return 0;
428 }
429 
430 /**
431  * ima_file_mmap - based on policy, collect/store measurement.
432  * @file: pointer to the file to be measured (May be NULL)
433  * @reqprot: protection requested by the application
434  * @prot: protection that will be applied by the kernel
435  * @flags: operational flags
436  *
437  * Measure files being mmapped executable based on the ima_must_measure()
438  * policy decision.
439  *
440  * On success return 0.  On integrity appraisal error, assuming the file
441  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
442  */
ima_file_mmap(struct file * file,unsigned long reqprot,unsigned long prot,unsigned long flags)443 static int ima_file_mmap(struct file *file, unsigned long reqprot,
444 			 unsigned long prot, unsigned long flags)
445 {
446 	struct lsm_prop prop;
447 	int ret;
448 
449 	if (!file)
450 		return 0;
451 
452 	security_current_getlsmprop_subj(&prop);
453 
454 	if (reqprot & PROT_EXEC) {
455 		ret = process_measurement(file, current_cred(), &prop, NULL,
456 					  0, MAY_EXEC, MMAP_CHECK_REQPROT);
457 		if (ret)
458 			return ret;
459 	}
460 
461 	if (prot & PROT_EXEC)
462 		return process_measurement(file, current_cred(), &prop, NULL,
463 					   0, MAY_EXEC, MMAP_CHECK);
464 
465 	return 0;
466 }
467 
468 /**
469  * ima_file_mprotect - based on policy, limit mprotect change
470  * @vma: vm_area_struct protection is set to
471  * @reqprot: protection requested by the application
472  * @prot: protection that will be applied by the kernel
473  *
474  * Files can be mmap'ed read/write and later changed to execute to circumvent
475  * IMA's mmap appraisal policy rules.  Due to locking issues (mmap semaphore
476  * would be taken before i_mutex), files can not be measured or appraised at
477  * this point.  Eliminate this integrity gap by denying the mprotect
478  * PROT_EXECUTE change, if an mmap appraise policy rule exists.
479  *
480  * On mprotect change success, return 0.  On failure, return -EACESS.
481  */
ima_file_mprotect(struct vm_area_struct * vma,unsigned long reqprot,unsigned long prot)482 static int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
483 			     unsigned long prot)
484 {
485 	struct ima_template_desc *template = NULL;
486 	struct file *file;
487 	char filename[NAME_MAX];
488 	char *pathbuf = NULL;
489 	const char *pathname = NULL;
490 	struct inode *inode;
491 	struct lsm_prop prop;
492 	int result = 0;
493 	int action;
494 	int pcr;
495 
496 	/* Is mprotect making an mmap'ed file executable? */
497 	if (!(ima_policy_flag & IMA_APPRAISE) || !vma->vm_file ||
498 	    !(prot & PROT_EXEC) || (vma->vm_flags & VM_EXEC))
499 		return 0;
500 
501 	security_current_getlsmprop_subj(&prop);
502 	inode = file_inode(vma->vm_file);
503 	action = ima_get_action(file_mnt_idmap(vma->vm_file), inode,
504 				current_cred(), &prop, MAY_EXEC, MMAP_CHECK,
505 				&pcr, &template, NULL, NULL);
506 	action |= ima_get_action(file_mnt_idmap(vma->vm_file), inode,
507 				 current_cred(), &prop, MAY_EXEC,
508 				 MMAP_CHECK_REQPROT, &pcr, &template, NULL,
509 				 NULL);
510 
511 	/* Is the mmap'ed file in policy? */
512 	if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
513 		return 0;
514 
515 	if (action & IMA_APPRAISE_SUBMASK)
516 		result = -EPERM;
517 
518 	file = vma->vm_file;
519 	pathname = ima_d_path(&file->f_path, &pathbuf, filename);
520 	integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, pathname,
521 			    "collect_data", "failed-mprotect", result, 0);
522 	if (pathbuf)
523 		__putname(pathbuf);
524 
525 	return result;
526 }
527 
528 /**
529  * ima_bprm_check - based on policy, collect/store measurement.
530  * @bprm: contains the linux_binprm structure
531  *
532  * The OS protects against an executable file, already open for write,
533  * from being executed in deny_write_access() and an executable file,
534  * already open for execute, from being modified in get_write_access().
535  * So we can be certain that what we verify and measure here is actually
536  * what is being executed.
537  *
538  * On success return 0.  On integrity appraisal error, assuming the file
539  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
540  */
ima_bprm_check(struct linux_binprm * bprm)541 static int ima_bprm_check(struct linux_binprm *bprm)
542 {
543 	int ret;
544 	struct lsm_prop prop;
545 
546 	security_current_getlsmprop_subj(&prop);
547 	ret = process_measurement(bprm->file, current_cred(),
548 				  &prop, NULL, 0, MAY_EXEC, BPRM_CHECK);
549 	if (ret)
550 		return ret;
551 
552 	security_cred_getlsmprop(bprm->cred, &prop);
553 	return process_measurement(bprm->file, bprm->cred, &prop, NULL, 0,
554 				   MAY_EXEC, CREDS_CHECK);
555 }
556 
557 /**
558  * ima_file_check - based on policy, collect/store measurement.
559  * @file: pointer to the file to be measured
560  * @mask: contains MAY_READ, MAY_WRITE, MAY_EXEC or MAY_APPEND
561  *
562  * Measure files based on the ima_must_measure() policy decision.
563  *
564  * On success return 0.  On integrity appraisal error, assuming the file
565  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
566  */
ima_file_check(struct file * file,int mask)567 static int ima_file_check(struct file *file, int mask)
568 {
569 	struct lsm_prop prop;
570 
571 	security_current_getlsmprop_subj(&prop);
572 	return process_measurement(file, current_cred(), &prop, NULL, 0,
573 				   mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
574 					   MAY_APPEND), FILE_CHECK);
575 }
576 
__ima_inode_hash(struct inode * inode,struct file * file,char * buf,size_t buf_size)577 static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf,
578 			    size_t buf_size)
579 {
580 	struct ima_iint_cache *iint = NULL, tmp_iint;
581 	int rc, hash_algo;
582 
583 	if (ima_policy_flag) {
584 		iint = ima_iint_find(inode);
585 		if (iint)
586 			mutex_lock(&iint->mutex);
587 	}
588 
589 	if ((!iint || !(iint->flags & IMA_COLLECTED)) && file) {
590 		if (iint)
591 			mutex_unlock(&iint->mutex);
592 
593 		memset(&tmp_iint, 0, sizeof(tmp_iint));
594 		mutex_init(&tmp_iint.mutex);
595 
596 		rc = ima_collect_measurement(&tmp_iint, file, NULL, 0,
597 					     ima_hash_algo, NULL);
598 		if (rc < 0) {
599 			/* ima_hash could be allocated in case of failure. */
600 			if (rc != -ENOMEM)
601 				kfree(tmp_iint.ima_hash);
602 
603 			return -EOPNOTSUPP;
604 		}
605 
606 		iint = &tmp_iint;
607 		mutex_lock(&iint->mutex);
608 	}
609 
610 	if (!iint)
611 		return -EOPNOTSUPP;
612 
613 	/*
614 	 * ima_file_hash can be called when ima_collect_measurement has still
615 	 * not been called, we might not always have a hash.
616 	 */
617 	if (!iint->ima_hash || !(iint->flags & IMA_COLLECTED)) {
618 		mutex_unlock(&iint->mutex);
619 		return -EOPNOTSUPP;
620 	}
621 
622 	if (buf) {
623 		size_t copied_size;
624 
625 		copied_size = min_t(size_t, iint->ima_hash->length, buf_size);
626 		memcpy(buf, iint->ima_hash->digest, copied_size);
627 	}
628 	hash_algo = iint->ima_hash->algo;
629 	mutex_unlock(&iint->mutex);
630 
631 	if (iint == &tmp_iint)
632 		kfree(iint->ima_hash);
633 
634 	return hash_algo;
635 }
636 
637 /**
638  * ima_file_hash - return a measurement of the file
639  * @file: pointer to the file
640  * @buf: buffer in which to store the hash
641  * @buf_size: length of the buffer
642  *
643  * On success, return the hash algorithm (as defined in the enum hash_algo).
644  * If buf is not NULL, this function also outputs the hash into buf.
645  * If the hash is larger than buf_size, then only buf_size bytes will be copied.
646  * It generally just makes sense to pass a buffer capable of holding the largest
647  * possible hash: IMA_MAX_DIGEST_SIZE.
648  * The file hash returned is based on the entire file, including the appended
649  * signature.
650  *
651  * If the measurement cannot be performed, return -EOPNOTSUPP.
652  * If the parameters are incorrect, return -EINVAL.
653  */
ima_file_hash(struct file * file,char * buf,size_t buf_size)654 int ima_file_hash(struct file *file, char *buf, size_t buf_size)
655 {
656 	if (!file)
657 		return -EINVAL;
658 
659 	return __ima_inode_hash(file_inode(file), file, buf, buf_size);
660 }
661 EXPORT_SYMBOL_GPL(ima_file_hash);
662 
663 /**
664  * ima_inode_hash - return the stored measurement if the inode has been hashed
665  * and is in the iint cache.
666  * @inode: pointer to the inode
667  * @buf: buffer in which to store the hash
668  * @buf_size: length of the buffer
669  *
670  * On success, return the hash algorithm (as defined in the enum hash_algo).
671  * If buf is not NULL, this function also outputs the hash into buf.
672  * If the hash is larger than buf_size, then only buf_size bytes will be copied.
673  * It generally just makes sense to pass a buffer capable of holding the largest
674  * possible hash: IMA_MAX_DIGEST_SIZE.
675  * The hash returned is based on the entire contents, including the appended
676  * signature.
677  *
678  * If IMA is disabled or if no measurement is available, return -EOPNOTSUPP.
679  * If the parameters are incorrect, return -EINVAL.
680  */
ima_inode_hash(struct inode * inode,char * buf,size_t buf_size)681 int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size)
682 {
683 	if (!inode)
684 		return -EINVAL;
685 
686 	return __ima_inode_hash(inode, NULL, buf, buf_size);
687 }
688 EXPORT_SYMBOL_GPL(ima_inode_hash);
689 
690 /**
691  * ima_post_create_tmpfile - mark newly created tmpfile as new
692  * @idmap: idmap of the mount the inode was found from
693  * @inode: inode of the newly created tmpfile
694  *
695  * No measuring, appraising or auditing of newly created tmpfiles is needed.
696  * Skip calling process_measurement(), but indicate which newly, created
697  * tmpfiles are in policy.
698  */
ima_post_create_tmpfile(struct mnt_idmap * idmap,struct inode * inode)699 static void ima_post_create_tmpfile(struct mnt_idmap *idmap,
700 				    struct inode *inode)
701 
702 {
703 	struct ima_iint_cache *iint;
704 	int must_appraise;
705 
706 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
707 		return;
708 
709 	must_appraise = ima_must_appraise(idmap, inode, MAY_ACCESS,
710 					  FILE_CHECK);
711 	if (!must_appraise)
712 		return;
713 
714 	/* Nothing to do if we can't allocate memory */
715 	iint = ima_inode_get(inode);
716 	if (!iint)
717 		return;
718 
719 	/* needed for writing the security xattrs */
720 	set_bit(IMA_UPDATE_XATTR, &iint->atomic_flags);
721 	iint->ima_file_status = INTEGRITY_PASS;
722 }
723 
724 /**
725  * ima_post_path_mknod - mark as a new inode
726  * @idmap: idmap of the mount the inode was found from
727  * @dentry: newly created dentry
728  *
729  * Mark files created via the mknodat syscall as new, so that the
730  * file data can be written later.
731  */
ima_post_path_mknod(struct mnt_idmap * idmap,struct dentry * dentry)732 static void ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
733 {
734 	struct ima_iint_cache *iint;
735 	struct inode *inode = dentry->d_inode;
736 	int must_appraise;
737 
738 	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
739 		return;
740 
741 	must_appraise = ima_must_appraise(idmap, inode, MAY_ACCESS,
742 					  FILE_CHECK);
743 	if (!must_appraise)
744 		return;
745 
746 	/* Nothing to do if we can't allocate memory */
747 	iint = ima_inode_get(inode);
748 	if (!iint)
749 		return;
750 
751 	/* needed for re-opening empty files */
752 	iint->flags |= IMA_NEW_FILE;
753 }
754 
755 /**
756  * ima_read_file - pre-measure/appraise hook decision based on policy
757  * @file: pointer to the file to be measured/appraised/audit
758  * @read_id: caller identifier
759  * @contents: whether a subsequent call will be made to ima_post_read_file()
760  *
761  * Permit reading a file based on policy. The policy rules are written
762  * in terms of the policy identifier.  Appraising the integrity of
763  * a file requires a file descriptor.
764  *
765  * For permission return 0, otherwise return -EACCES.
766  */
ima_read_file(struct file * file,enum kernel_read_file_id read_id,bool contents)767 static int ima_read_file(struct file *file, enum kernel_read_file_id read_id,
768 			 bool contents)
769 {
770 	enum ima_hooks func;
771 	struct lsm_prop prop;
772 
773 	/*
774 	 * Do devices using pre-allocated memory run the risk of the
775 	 * firmware being accessible to the device prior to the completion
776 	 * of IMA's signature verification any more than when using two
777 	 * buffers? It may be desirable to include the buffer address
778 	 * in this API and walk all the dma_map_single() mappings to check.
779 	 */
780 
781 	/*
782 	 * There will be a call made to ima_post_read_file() with
783 	 * a filled buffer, so we don't need to perform an extra
784 	 * read early here.
785 	 */
786 	if (contents)
787 		return 0;
788 
789 	/* Read entire file for all partial reads. */
790 	func = read_idmap[read_id] ?: FILE_CHECK;
791 	security_current_getlsmprop_subj(&prop);
792 	return process_measurement(file, current_cred(), &prop, NULL, 0,
793 				   MAY_READ, func);
794 }
795 
796 const int read_idmap[READING_MAX_ID] = {
797 	[READING_FIRMWARE] = FIRMWARE_CHECK,
798 	[READING_MODULE] = MODULE_CHECK,
799 	[READING_KEXEC_IMAGE] = KEXEC_KERNEL_CHECK,
800 	[READING_KEXEC_INITRAMFS] = KEXEC_INITRAMFS_CHECK,
801 	[READING_POLICY] = POLICY_CHECK
802 };
803 
804 /**
805  * ima_post_read_file - in memory collect/appraise/audit measurement
806  * @file: pointer to the file to be measured/appraised/audit
807  * @buf: pointer to in memory file contents
808  * @size: size of in memory file contents
809  * @read_id: caller identifier
810  *
811  * Measure/appraise/audit in memory file based on policy.  Policy rules
812  * are written in terms of a policy identifier.
813  *
814  * On success return 0.  On integrity appraisal error, assuming the file
815  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
816  */
ima_post_read_file(struct file * file,char * buf,loff_t size,enum kernel_read_file_id read_id)817 static int ima_post_read_file(struct file *file, char *buf, loff_t size,
818 			      enum kernel_read_file_id read_id)
819 {
820 	enum ima_hooks func;
821 	struct lsm_prop prop;
822 
823 	/* permit signed certs */
824 	if (!file && read_id == READING_X509_CERTIFICATE)
825 		return 0;
826 
827 	if (!file || !buf || size == 0) { /* should never happen */
828 		if (ima_appraise & IMA_APPRAISE_ENFORCE)
829 			return -EACCES;
830 		return 0;
831 	}
832 
833 	func = read_idmap[read_id] ?: FILE_CHECK;
834 	security_current_getlsmprop_subj(&prop);
835 	return process_measurement(file, current_cred(), &prop, buf, size,
836 				   MAY_READ, func);
837 }
838 
839 /**
840  * ima_load_data - appraise decision based on policy
841  * @id: kernel load data caller identifier
842  * @contents: whether the full contents will be available in a later
843  *	      call to ima_post_load_data().
844  *
845  * Callers of this LSM hook can not measure, appraise, or audit the
846  * data provided by userspace.  Enforce policy rules requiring a file
847  * signature (eg. kexec'ed kernel image).
848  *
849  * For permission return 0, otherwise return -EACCES.
850  */
ima_load_data(enum kernel_load_data_id id,bool contents)851 static int ima_load_data(enum kernel_load_data_id id, bool contents)
852 {
853 	bool ima_enforce, sig_enforce;
854 
855 	ima_enforce =
856 		(ima_appraise & IMA_APPRAISE_ENFORCE) == IMA_APPRAISE_ENFORCE;
857 
858 	switch (id) {
859 	case LOADING_KEXEC_IMAGE:
860 		if (IS_ENABLED(CONFIG_KEXEC_SIG)
861 		    && arch_ima_get_secureboot()) {
862 			pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load syscall.\n");
863 			return -EACCES;
864 		}
865 
866 		if (ima_enforce && (ima_appraise & IMA_APPRAISE_KEXEC)) {
867 			pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load syscall.\n");
868 			return -EACCES;	/* INTEGRITY_UNKNOWN */
869 		}
870 		break;
871 	case LOADING_FIRMWARE:
872 		if (ima_enforce && (ima_appraise & IMA_APPRAISE_FIRMWARE) && !contents) {
873 			pr_err("Prevent firmware sysfs fallback loading.\n");
874 			return -EACCES;	/* INTEGRITY_UNKNOWN */
875 		}
876 		break;
877 	case LOADING_MODULE:
878 		sig_enforce = is_module_sig_enforced();
879 
880 		if (ima_enforce && (!sig_enforce
881 				    && (ima_appraise & IMA_APPRAISE_MODULES))) {
882 			pr_err("impossible to appraise a module without a file descriptor. sig_enforce kernel parameter might help\n");
883 			return -EACCES;	/* INTEGRITY_UNKNOWN */
884 		}
885 		break;
886 	default:
887 		break;
888 	}
889 	return 0;
890 }
891 
892 /**
893  * ima_post_load_data - appraise decision based on policy
894  * @buf: pointer to in memory file contents
895  * @size: size of in memory file contents
896  * @load_id: kernel load data caller identifier
897  * @description: @load_id-specific description of contents
898  *
899  * Measure/appraise/audit in memory buffer based on policy.  Policy rules
900  * are written in terms of a policy identifier.
901  *
902  * On success return 0.  On integrity appraisal error, assuming the file
903  * is in policy and IMA-appraisal is in enforcing mode, return -EACCES.
904  */
ima_post_load_data(char * buf,loff_t size,enum kernel_load_data_id load_id,char * description)905 static int ima_post_load_data(char *buf, loff_t size,
906 			      enum kernel_load_data_id load_id,
907 			      char *description)
908 {
909 	if (load_id == LOADING_FIRMWARE) {
910 		if ((ima_appraise & IMA_APPRAISE_FIRMWARE) &&
911 		    (ima_appraise & IMA_APPRAISE_ENFORCE)) {
912 			pr_err("Prevent firmware loading_store.\n");
913 			return -EACCES; /* INTEGRITY_UNKNOWN */
914 		}
915 		return 0;
916 	}
917 
918 	/*
919 	 * Measure the init_module syscall buffer containing the ELF image.
920 	 */
921 	if (load_id == LOADING_MODULE)
922 		ima_measure_critical_data("modules", "init_module",
923 					  buf, size, true, NULL, 0);
924 
925 	return 0;
926 }
927 
928 /**
929  * process_buffer_measurement - Measure the buffer or the buffer data hash
930  * @idmap: idmap of the mount the inode was found from
931  * @inode: inode associated with the object being measured (NULL for KEY_CHECK)
932  * @buf: pointer to the buffer that needs to be added to the log.
933  * @size: size of buffer(in bytes).
934  * @eventname: event name to be used for the buffer entry.
935  * @func: IMA hook
936  * @pcr: pcr to extend the measurement
937  * @func_data: func specific data, may be NULL
938  * @buf_hash: measure buffer data hash
939  * @digest: buffer digest will be written to
940  * @digest_len: buffer length
941  *
942  * Based on policy, either the buffer data or buffer data hash is measured
943  *
944  * Return: 0 if the buffer has been successfully measured, 1 if the digest
945  * has been written to the passed location but not added to a measurement entry,
946  * a negative value otherwise.
947  */
process_buffer_measurement(struct mnt_idmap * idmap,struct inode * inode,const void * buf,int size,const char * eventname,enum ima_hooks func,int pcr,const char * func_data,bool buf_hash,u8 * digest,size_t digest_len)948 int process_buffer_measurement(struct mnt_idmap *idmap,
949 			       struct inode *inode, const void *buf, int size,
950 			       const char *eventname, enum ima_hooks func,
951 			       int pcr, const char *func_data,
952 			       bool buf_hash, u8 *digest, size_t digest_len)
953 {
954 	int ret = 0;
955 	const char *audit_cause = "ENOMEM";
956 	struct ima_template_entry *entry = NULL;
957 	struct ima_iint_cache iint = {};
958 	struct ima_event_data event_data = {.iint = &iint,
959 					    .filename = eventname,
960 					    .buf = buf,
961 					    .buf_len = size};
962 	struct ima_template_desc *template;
963 	struct ima_max_digest_data hash;
964 	struct ima_digest_data *hash_hdr = container_of(&hash.hdr,
965 						struct ima_digest_data, hdr);
966 	char digest_hash[IMA_MAX_DIGEST_SIZE];
967 	int digest_hash_len = hash_digest_size[ima_hash_algo];
968 	int violation = 0;
969 	int action = 0;
970 	struct lsm_prop prop;
971 
972 	if (digest && digest_len < digest_hash_len)
973 		return -EINVAL;
974 
975 	if (!ima_policy_flag && !digest)
976 		return -ENOENT;
977 
978 	template = ima_template_desc_buf();
979 	if (!template) {
980 		ret = -EINVAL;
981 		audit_cause = "ima_template_desc_buf";
982 		goto out;
983 	}
984 
985 	/*
986 	 * Both LSM hooks and auxilary based buffer measurements are
987 	 * based on policy.  To avoid code duplication, differentiate
988 	 * between the LSM hooks and auxilary buffer measurements,
989 	 * retrieving the policy rule information only for the LSM hook
990 	 * buffer measurements.
991 	 */
992 	if (func) {
993 		security_current_getlsmprop_subj(&prop);
994 		action = ima_get_action(idmap, inode, current_cred(),
995 					&prop, 0, func, &pcr, &template,
996 					func_data, NULL);
997 		if (!(action & IMA_MEASURE) && !digest)
998 			return -ENOENT;
999 	}
1000 
1001 	if (!pcr)
1002 		pcr = CONFIG_IMA_MEASURE_PCR_IDX;
1003 
1004 	iint.ima_hash = hash_hdr;
1005 	iint.ima_hash->algo = ima_hash_algo;
1006 	iint.ima_hash->length = hash_digest_size[ima_hash_algo];
1007 
1008 	ret = ima_calc_buffer_hash(buf, size, iint.ima_hash);
1009 	if (ret < 0) {
1010 		audit_cause = "hashing_error";
1011 		goto out;
1012 	}
1013 
1014 	if (buf_hash) {
1015 		memcpy(digest_hash, hash_hdr->digest, digest_hash_len);
1016 
1017 		ret = ima_calc_buffer_hash(digest_hash, digest_hash_len,
1018 					   iint.ima_hash);
1019 		if (ret < 0) {
1020 			audit_cause = "hashing_error";
1021 			goto out;
1022 		}
1023 
1024 		event_data.buf = digest_hash;
1025 		event_data.buf_len = digest_hash_len;
1026 	}
1027 
1028 	if (digest)
1029 		memcpy(digest, iint.ima_hash->digest, digest_hash_len);
1030 
1031 	if (!ima_policy_flag || (func && !(action & IMA_MEASURE)))
1032 		return 1;
1033 
1034 	ret = ima_alloc_init_template(&event_data, &entry, template);
1035 	if (ret < 0) {
1036 		audit_cause = "alloc_entry";
1037 		goto out;
1038 	}
1039 
1040 	ret = ima_store_template(entry, violation, NULL, event_data.buf, pcr);
1041 	if (ret < 0) {
1042 		audit_cause = "store_entry";
1043 		ima_free_template_entry(entry);
1044 	}
1045 
1046 out:
1047 	if (ret < 0)
1048 		integrity_audit_message(AUDIT_INTEGRITY_PCR, NULL, eventname,
1049 					func_measure_str(func),
1050 					audit_cause, ret, 0, ret);
1051 
1052 	return ret;
1053 }
1054 
1055 /**
1056  * ima_kexec_cmdline - measure kexec cmdline boot args
1057  * @kernel_fd: file descriptor of the kexec kernel being loaded
1058  * @buf: pointer to buffer
1059  * @size: size of buffer
1060  *
1061  * Buffers can only be measured, not appraised.
1062  */
ima_kexec_cmdline(int kernel_fd,const void * buf,int size)1063 void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
1064 {
1065 	if (!buf || !size)
1066 		return;
1067 
1068 	CLASS(fd, f)(kernel_fd);
1069 	if (fd_empty(f))
1070 		return;
1071 
1072 	process_buffer_measurement(file_mnt_idmap(fd_file(f)), file_inode(fd_file(f)),
1073 				   buf, size, "kexec-cmdline", KEXEC_CMDLINE, 0,
1074 				   NULL, false, NULL, 0);
1075 }
1076 
1077 /**
1078  * ima_measure_critical_data - measure kernel integrity critical data
1079  * @event_label: unique event label for grouping and limiting critical data
1080  * @event_name: event name for the record in the IMA measurement list
1081  * @buf: pointer to buffer data
1082  * @buf_len: length of buffer data (in bytes)
1083  * @hash: measure buffer data hash
1084  * @digest: buffer digest will be written to
1085  * @digest_len: buffer length
1086  *
1087  * Measure data critical to the integrity of the kernel into the IMA log
1088  * and extend the pcr.  Examples of critical data could be various data
1089  * structures, policies, and states stored in kernel memory that can
1090  * impact the integrity of the system.
1091  *
1092  * Return: 0 if the buffer has been successfully measured, 1 if the digest
1093  * has been written to the passed location but not added to a measurement entry,
1094  * a negative value otherwise.
1095  */
ima_measure_critical_data(const char * event_label,const char * event_name,const void * buf,size_t buf_len,bool hash,u8 * digest,size_t digest_len)1096 int ima_measure_critical_data(const char *event_label,
1097 			      const char *event_name,
1098 			      const void *buf, size_t buf_len,
1099 			      bool hash, u8 *digest, size_t digest_len)
1100 {
1101 	if (!event_name || !event_label || !buf || !buf_len)
1102 		return -ENOPARAM;
1103 
1104 	return process_buffer_measurement(&nop_mnt_idmap, NULL, buf, buf_len,
1105 					  event_name, CRITICAL_DATA, 0,
1106 					  event_label, hash, digest,
1107 					  digest_len);
1108 }
1109 EXPORT_SYMBOL_GPL(ima_measure_critical_data);
1110 
1111 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
1112 
1113 /**
1114  * ima_kernel_module_request - Prevent crypto-pkcs1(rsa,*) requests
1115  * @kmod_name: kernel module name
1116  *
1117  * Avoid a verification loop where verifying the signature of the modprobe
1118  * binary requires executing modprobe itself. Since the modprobe iint->mutex
1119  * is already held when the signature verification is performed, a deadlock
1120  * occurs as soon as modprobe is executed within the critical region, since
1121  * the same lock cannot be taken again.
1122  *
1123  * This happens when public_key_verify_signature(), in case of RSA algorithm,
1124  * use alg_name to store internal information in order to construct an
1125  * algorithm on the fly, but crypto_larval_lookup() will try to use alg_name
1126  * in order to load a kernel module with same name.
1127  *
1128  * Since we don't have any real "crypto-pkcs1(rsa,*)" kernel modules,
1129  * we are safe to fail such module request from crypto_larval_lookup(), and
1130  * avoid the verification loop.
1131  *
1132  * Return: Zero if it is safe to load the kernel module, -EINVAL otherwise.
1133  */
ima_kernel_module_request(char * kmod_name)1134 static int ima_kernel_module_request(char *kmod_name)
1135 {
1136 	if (strncmp(kmod_name, "crypto-pkcs1(rsa,", 17) == 0)
1137 		return -EINVAL;
1138 
1139 	return 0;
1140 }
1141 
1142 #endif /* CONFIG_INTEGRITY_ASYMMETRIC_KEYS */
1143 
init_ima(void)1144 static int __init init_ima(void)
1145 {
1146 	int error;
1147 
1148 	ima_appraise_parse_cmdline();
1149 	ima_init_template_list();
1150 	hash_setup(CONFIG_IMA_DEFAULT_HASH);
1151 	error = ima_init();
1152 
1153 	if (error && strcmp(hash_algo_name[ima_hash_algo],
1154 			    CONFIG_IMA_DEFAULT_HASH) != 0) {
1155 		pr_info("Allocating %s failed, going to use default hash algorithm %s\n",
1156 			hash_algo_name[ima_hash_algo], CONFIG_IMA_DEFAULT_HASH);
1157 		hash_setup_done = 0;
1158 		hash_setup(CONFIG_IMA_DEFAULT_HASH);
1159 		error = ima_init();
1160 	}
1161 
1162 	if (error)
1163 		return error;
1164 
1165 	error = register_blocking_lsm_notifier(&ima_lsm_policy_notifier);
1166 	if (error)
1167 		pr_warn("Couldn't register LSM notifier, error %d\n", error);
1168 
1169 	if (!error)
1170 		ima_update_policy_flags();
1171 
1172 	return error;
1173 }
1174 
1175 static struct security_hook_list ima_hooks[] __ro_after_init = {
1176 	LSM_HOOK_INIT(bprm_check_security, ima_bprm_check),
1177 	LSM_HOOK_INIT(file_post_open, ima_file_check),
1178 	LSM_HOOK_INIT(inode_post_create_tmpfile, ima_post_create_tmpfile),
1179 	LSM_HOOK_INIT(file_release, ima_file_free),
1180 	LSM_HOOK_INIT(mmap_file, ima_file_mmap),
1181 	LSM_HOOK_INIT(file_mprotect, ima_file_mprotect),
1182 	LSM_HOOK_INIT(kernel_load_data, ima_load_data),
1183 	LSM_HOOK_INIT(kernel_post_load_data, ima_post_load_data),
1184 	LSM_HOOK_INIT(kernel_read_file, ima_read_file),
1185 	LSM_HOOK_INIT(kernel_post_read_file, ima_post_read_file),
1186 	LSM_HOOK_INIT(path_post_mknod, ima_post_path_mknod),
1187 #ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
1188 	LSM_HOOK_INIT(key_post_create_or_update, ima_post_key_create_or_update),
1189 #endif
1190 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
1191 	LSM_HOOK_INIT(kernel_module_request, ima_kernel_module_request),
1192 #endif
1193 	LSM_HOOK_INIT(inode_free_security_rcu, ima_inode_free_rcu),
1194 };
1195 
1196 static const struct lsm_id ima_lsmid = {
1197 	.name = "ima",
1198 	.id = LSM_ID_IMA,
1199 };
1200 
init_ima_lsm(void)1201 static int __init init_ima_lsm(void)
1202 {
1203 	ima_iintcache_init();
1204 	security_add_hooks(ima_hooks, ARRAY_SIZE(ima_hooks), &ima_lsmid);
1205 	init_ima_appraise_lsm(&ima_lsmid);
1206 	return 0;
1207 }
1208 
1209 struct lsm_blob_sizes ima_blob_sizes __ro_after_init = {
1210 	.lbs_inode = sizeof(struct ima_iint_cache *),
1211 };
1212 
1213 DEFINE_LSM(ima) = {
1214 	.name = "ima",
1215 	.init = init_ima_lsm,
1216 	.order = LSM_ORDER_LAST,
1217 	.blobs = &ima_blob_sizes,
1218 };
1219 
1220 late_initcall(init_ima);	/* Start IMA after the TPM is available */
1221