1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2008 IBM Corporation
4  * Author: Mimi Zohar <zohar@us.ibm.com>
5  *
6  * ima_policy.c
7  *	- initialize default measure policy rules
8  */
9 #include <linux/init.h>
10 #include <linux/list.h>
11 #include <linux/fs.h>
12 #include <linux/security.h>
13 #include <linux/magic.h>
14 #include <linux/parser.h>
15 #include <linux/slab.h>
16 #include <linux/rculist.h>
17 #include <linux/genhd.h>
18 #include <linux/seq_file.h>
19 #include <linux/ima.h>
20 
21 #include "ima.h"
22 
23 /* flags definitions */
24 #define IMA_FUNC	0x0001
25 #define IMA_MASK	0x0002
26 #define IMA_FSMAGIC	0x0004
27 #define IMA_UID		0x0008
28 #define IMA_FOWNER	0x0010
29 #define IMA_FSUUID	0x0020
30 #define IMA_INMASK	0x0040
31 #define IMA_EUID	0x0080
32 #define IMA_PCR		0x0100
33 #define IMA_FSNAME	0x0200
34 
35 #define UNKNOWN		0
36 #define MEASURE		0x0001	/* same as IMA_MEASURE */
37 #define DONT_MEASURE	0x0002
38 #define APPRAISE	0x0004	/* same as IMA_APPRAISE */
39 #define DONT_APPRAISE	0x0008
40 #define AUDIT		0x0040
41 #define HASH		0x0100
42 #define DONT_HASH	0x0200
43 
44 #define INVALID_PCR(a) (((a) < 0) || \
45 	(a) >= (FIELD_SIZEOF(struct integrity_iint_cache, measured_pcrs) * 8))
46 
47 int ima_policy_flag;
48 static int temp_ima_appraise;
49 static int build_ima_appraise __ro_after_init;
50 
51 #define MAX_LSM_RULES 6
52 enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
53 	LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
54 };
55 
56 enum policy_types { ORIGINAL_TCB = 1, DEFAULT_TCB };
57 
58 enum policy_rule_list { IMA_DEFAULT_POLICY = 1, IMA_CUSTOM_POLICY };
59 
60 struct ima_rule_entry {
61 	struct list_head list;
62 	int action;
63 	unsigned int flags;
64 	enum ima_hooks func;
65 	int mask;
66 	unsigned long fsmagic;
67 	uuid_t fsuuid;
68 	kuid_t uid;
69 	kuid_t fowner;
70 	bool (*uid_op)(kuid_t, kuid_t);    /* Handlers for operators       */
71 	bool (*fowner_op)(kuid_t, kuid_t); /* uid_eq(), uid_gt(), uid_lt() */
72 	int pcr;
73 	struct {
74 		void *rule;	/* LSM file metadata specific */
75 		void *args_p;	/* audit value */
76 		int type;	/* audit type */
77 	} lsm[MAX_LSM_RULES];
78 	char *fsname;
79 };
80 
81 /*
82  * Without LSM specific knowledge, the default policy can only be
83  * written in terms of .action, .func, .mask, .fsmagic, .uid, and .fowner
84  */
85 
86 /*
87  * The minimum rule set to allow for full TCB coverage.  Measures all files
88  * opened or mmap for exec and everything read by root.  Dangerous because
89  * normal users can easily run the machine out of memory simply building
90  * and running executables.
91  */
92 static struct ima_rule_entry dont_measure_rules[] __ro_after_init = {
93 	{.action = DONT_MEASURE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
94 	{.action = DONT_MEASURE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
95 	{.action = DONT_MEASURE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
96 	{.action = DONT_MEASURE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
97 	{.action = DONT_MEASURE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
98 	{.action = DONT_MEASURE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
99 	{.action = DONT_MEASURE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
100 	{.action = DONT_MEASURE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
101 	{.action = DONT_MEASURE, .fsmagic = SMACK_MAGIC, .flags = IMA_FSMAGIC},
102 	{.action = DONT_MEASURE, .fsmagic = CGROUP_SUPER_MAGIC,
103 	 .flags = IMA_FSMAGIC},
104 	{.action = DONT_MEASURE, .fsmagic = CGROUP2_SUPER_MAGIC,
105 	 .flags = IMA_FSMAGIC},
106 	{.action = DONT_MEASURE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
107 	{.action = DONT_MEASURE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC}
108 };
109 
110 static struct ima_rule_entry original_measurement_rules[] __ro_after_init = {
111 	{.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
112 	 .flags = IMA_FUNC | IMA_MASK},
113 	{.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
114 	 .flags = IMA_FUNC | IMA_MASK},
115 	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
116 	 .uid = GLOBAL_ROOT_UID, .uid_op = &uid_eq,
117 	 .flags = IMA_FUNC | IMA_MASK | IMA_UID},
118 	{.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
119 	{.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
120 };
121 
122 static struct ima_rule_entry default_measurement_rules[] __ro_after_init = {
123 	{.action = MEASURE, .func = MMAP_CHECK, .mask = MAY_EXEC,
124 	 .flags = IMA_FUNC | IMA_MASK},
125 	{.action = MEASURE, .func = BPRM_CHECK, .mask = MAY_EXEC,
126 	 .flags = IMA_FUNC | IMA_MASK},
127 	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
128 	 .uid = GLOBAL_ROOT_UID, .uid_op = &uid_eq,
129 	 .flags = IMA_FUNC | IMA_INMASK | IMA_EUID},
130 	{.action = MEASURE, .func = FILE_CHECK, .mask = MAY_READ,
131 	 .uid = GLOBAL_ROOT_UID, .uid_op = &uid_eq,
132 	 .flags = IMA_FUNC | IMA_INMASK | IMA_UID},
133 	{.action = MEASURE, .func = MODULE_CHECK, .flags = IMA_FUNC},
134 	{.action = MEASURE, .func = FIRMWARE_CHECK, .flags = IMA_FUNC},
135 	{.action = MEASURE, .func = POLICY_CHECK, .flags = IMA_FUNC},
136 };
137 
138 static struct ima_rule_entry default_appraise_rules[] __ro_after_init = {
139 	{.action = DONT_APPRAISE, .fsmagic = PROC_SUPER_MAGIC, .flags = IMA_FSMAGIC},
140 	{.action = DONT_APPRAISE, .fsmagic = SYSFS_MAGIC, .flags = IMA_FSMAGIC},
141 	{.action = DONT_APPRAISE, .fsmagic = DEBUGFS_MAGIC, .flags = IMA_FSMAGIC},
142 	{.action = DONT_APPRAISE, .fsmagic = TMPFS_MAGIC, .flags = IMA_FSMAGIC},
143 	{.action = DONT_APPRAISE, .fsmagic = RAMFS_MAGIC, .flags = IMA_FSMAGIC},
144 	{.action = DONT_APPRAISE, .fsmagic = DEVPTS_SUPER_MAGIC, .flags = IMA_FSMAGIC},
145 	{.action = DONT_APPRAISE, .fsmagic = BINFMTFS_MAGIC, .flags = IMA_FSMAGIC},
146 	{.action = DONT_APPRAISE, .fsmagic = SECURITYFS_MAGIC, .flags = IMA_FSMAGIC},
147 	{.action = DONT_APPRAISE, .fsmagic = SELINUX_MAGIC, .flags = IMA_FSMAGIC},
148 	{.action = DONT_APPRAISE, .fsmagic = SMACK_MAGIC, .flags = IMA_FSMAGIC},
149 	{.action = DONT_APPRAISE, .fsmagic = NSFS_MAGIC, .flags = IMA_FSMAGIC},
150 	{.action = DONT_APPRAISE, .fsmagic = EFIVARFS_MAGIC, .flags = IMA_FSMAGIC},
151 	{.action = DONT_APPRAISE, .fsmagic = CGROUP_SUPER_MAGIC, .flags = IMA_FSMAGIC},
152 	{.action = DONT_APPRAISE, .fsmagic = CGROUP2_SUPER_MAGIC, .flags = IMA_FSMAGIC},
153 #ifdef CONFIG_IMA_WRITE_POLICY
154 	{.action = APPRAISE, .func = POLICY_CHECK,
155 	.flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
156 #endif
157 #ifndef CONFIG_IMA_APPRAISE_SIGNED_INIT
158 	{.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .fowner_op = &uid_eq,
159 	 .flags = IMA_FOWNER},
160 #else
161 	/* force signature */
162 	{.action = APPRAISE, .fowner = GLOBAL_ROOT_UID, .fowner_op = &uid_eq,
163 	 .flags = IMA_FOWNER | IMA_DIGSIG_REQUIRED},
164 #endif
165 };
166 
167 static struct ima_rule_entry build_appraise_rules[] __ro_after_init = {
168 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_MODULE_SIGS
169 	{.action = APPRAISE, .func = MODULE_CHECK,
170 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
171 #endif
172 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS
173 	{.action = APPRAISE, .func = FIRMWARE_CHECK,
174 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
175 #endif
176 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS
177 	{.action = APPRAISE, .func = KEXEC_KERNEL_CHECK,
178 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
179 #endif
180 #ifdef CONFIG_IMA_APPRAISE_REQUIRE_POLICY_SIGS
181 	{.action = APPRAISE, .func = POLICY_CHECK,
182 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
183 #endif
184 };
185 
186 static struct ima_rule_entry secure_boot_rules[] __ro_after_init = {
187 	{.action = APPRAISE, .func = MODULE_CHECK,
188 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
189 	{.action = APPRAISE, .func = FIRMWARE_CHECK,
190 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
191 	{.action = APPRAISE, .func = KEXEC_KERNEL_CHECK,
192 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
193 	{.action = APPRAISE, .func = POLICY_CHECK,
194 	 .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED},
195 };
196 
197 /* An array of architecture specific rules */
198 struct ima_rule_entry *arch_policy_entry __ro_after_init;
199 
200 static LIST_HEAD(ima_default_rules);
201 static LIST_HEAD(ima_policy_rules);
202 static LIST_HEAD(ima_temp_rules);
203 static struct list_head *ima_rules;
204 
205 static int ima_policy __initdata;
206 
207 static int __init default_measure_policy_setup(char *str)
208 {
209 	if (ima_policy)
210 		return 1;
211 
212 	ima_policy = ORIGINAL_TCB;
213 	return 1;
214 }
215 __setup("ima_tcb", default_measure_policy_setup);
216 
217 static bool ima_use_appraise_tcb __initdata;
218 static bool ima_use_secure_boot __initdata;
219 static bool ima_fail_unverifiable_sigs __ro_after_init;
220 static int __init policy_setup(char *str)
221 {
222 	char *p;
223 
224 	while ((p = strsep(&str, " |\n")) != NULL) {
225 		if (*p == ' ')
226 			continue;
227 		if ((strcmp(p, "tcb") == 0) && !ima_policy)
228 			ima_policy = DEFAULT_TCB;
229 		else if (strcmp(p, "appraise_tcb") == 0)
230 			ima_use_appraise_tcb = true;
231 		else if (strcmp(p, "secure_boot") == 0)
232 			ima_use_secure_boot = true;
233 		else if (strcmp(p, "fail_securely") == 0)
234 			ima_fail_unverifiable_sigs = true;
235 	}
236 
237 	return 1;
238 }
239 __setup("ima_policy=", policy_setup);
240 
241 static int __init default_appraise_policy_setup(char *str)
242 {
243 	ima_use_appraise_tcb = true;
244 	return 1;
245 }
246 __setup("ima_appraise_tcb", default_appraise_policy_setup);
247 
248 /*
249  * The LSM policy can be reloaded, leaving the IMA LSM based rules referring
250  * to the old, stale LSM policy.  Update the IMA LSM based rules to reflect
251  * the reloaded LSM policy.  We assume the rules still exist; and BUG_ON() if
252  * they don't.
253  */
254 static void ima_lsm_update_rules(void)
255 {
256 	struct ima_rule_entry *entry;
257 	int result;
258 	int i;
259 
260 	list_for_each_entry(entry, &ima_policy_rules, list) {
261 		for (i = 0; i < MAX_LSM_RULES; i++) {
262 			if (!entry->lsm[i].rule)
263 				continue;
264 			result = security_filter_rule_init(entry->lsm[i].type,
265 							   Audit_equal,
266 							   entry->lsm[i].args_p,
267 							   &entry->lsm[i].rule);
268 			BUG_ON(!entry->lsm[i].rule);
269 		}
270 	}
271 }
272 
273 /**
274  * ima_match_rules - determine whether an inode matches the measure rule.
275  * @rule: a pointer to a rule
276  * @inode: a pointer to an inode
277  * @cred: a pointer to a credentials structure for user validation
278  * @secid: the secid of the task to be validated
279  * @func: LIM hook identifier
280  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
281  *
282  * Returns true on rule match, false on failure.
283  */
284 static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
285 			    const struct cred *cred, u32 secid,
286 			    enum ima_hooks func, int mask)
287 {
288 	int i;
289 
290 	if ((rule->flags & IMA_FUNC) &&
291 	    (rule->func != func && func != POST_SETATTR))
292 		return false;
293 	if ((rule->flags & IMA_MASK) &&
294 	    (rule->mask != mask && func != POST_SETATTR))
295 		return false;
296 	if ((rule->flags & IMA_INMASK) &&
297 	    (!(rule->mask & mask) && func != POST_SETATTR))
298 		return false;
299 	if ((rule->flags & IMA_FSMAGIC)
300 	    && rule->fsmagic != inode->i_sb->s_magic)
301 		return false;
302 	if ((rule->flags & IMA_FSNAME)
303 	    && strcmp(rule->fsname, inode->i_sb->s_type->name))
304 		return false;
305 	if ((rule->flags & IMA_FSUUID) &&
306 	    !uuid_equal(&rule->fsuuid, &inode->i_sb->s_uuid))
307 		return false;
308 	if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid))
309 		return false;
310 	if (rule->flags & IMA_EUID) {
311 		if (has_capability_noaudit(current, CAP_SETUID)) {
312 			if (!rule->uid_op(cred->euid, rule->uid)
313 			    && !rule->uid_op(cred->suid, rule->uid)
314 			    && !rule->uid_op(cred->uid, rule->uid))
315 				return false;
316 		} else if (!rule->uid_op(cred->euid, rule->uid))
317 			return false;
318 	}
319 
320 	if ((rule->flags & IMA_FOWNER) &&
321 	    !rule->fowner_op(inode->i_uid, rule->fowner))
322 		return false;
323 	for (i = 0; i < MAX_LSM_RULES; i++) {
324 		int rc = 0;
325 		u32 osid;
326 		int retried = 0;
327 
328 		if (!rule->lsm[i].rule)
329 			continue;
330 retry:
331 		switch (i) {
332 		case LSM_OBJ_USER:
333 		case LSM_OBJ_ROLE:
334 		case LSM_OBJ_TYPE:
335 			security_inode_getsecid(inode, &osid);
336 			rc = security_filter_rule_match(osid,
337 							rule->lsm[i].type,
338 							Audit_equal,
339 							rule->lsm[i].rule);
340 			break;
341 		case LSM_SUBJ_USER:
342 		case LSM_SUBJ_ROLE:
343 		case LSM_SUBJ_TYPE:
344 			rc = security_filter_rule_match(secid,
345 							rule->lsm[i].type,
346 							Audit_equal,
347 							rule->lsm[i].rule);
348 		default:
349 			break;
350 		}
351 		if ((rc < 0) && (!retried)) {
352 			retried = 1;
353 			ima_lsm_update_rules();
354 			goto retry;
355 		}
356 		if (!rc)
357 			return false;
358 	}
359 	return true;
360 }
361 
362 /*
363  * In addition to knowing that we need to appraise the file in general,
364  * we need to differentiate between calling hooks, for hook specific rules.
365  */
366 static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
367 {
368 	if (!(rule->flags & IMA_FUNC))
369 		return IMA_FILE_APPRAISE;
370 
371 	switch (func) {
372 	case MMAP_CHECK:
373 		return IMA_MMAP_APPRAISE;
374 	case BPRM_CHECK:
375 		return IMA_BPRM_APPRAISE;
376 	case CREDS_CHECK:
377 		return IMA_CREDS_APPRAISE;
378 	case FILE_CHECK:
379 	case POST_SETATTR:
380 		return IMA_FILE_APPRAISE;
381 	case MODULE_CHECK ... MAX_CHECK - 1:
382 	default:
383 		return IMA_READ_APPRAISE;
384 	}
385 }
386 
387 /**
388  * ima_match_policy - decision based on LSM and other conditions
389  * @inode: pointer to an inode for which the policy decision is being made
390  * @cred: pointer to a credentials structure for which the policy decision is
391  *        being made
392  * @secid: LSM secid of the task to be validated
393  * @func: IMA hook identifier
394  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
395  * @pcr: set the pcr to extend
396  *
397  * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
398  * conditions.
399  *
400  * Since the IMA policy may be updated multiple times we need to lock the
401  * list when walking it.  Reads are many orders of magnitude more numerous
402  * than writes so ima_match_policy() is classical RCU candidate.
403  */
404 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
405 		     enum ima_hooks func, int mask, int flags, int *pcr)
406 {
407 	struct ima_rule_entry *entry;
408 	int action = 0, actmask = flags | (flags << 1);
409 
410 	rcu_read_lock();
411 	list_for_each_entry_rcu(entry, ima_rules, list) {
412 
413 		if (!(entry->action & actmask))
414 			continue;
415 
416 		if (!ima_match_rules(entry, inode, cred, secid, func, mask))
417 			continue;
418 
419 		action |= entry->flags & IMA_ACTION_FLAGS;
420 
421 		action |= entry->action & IMA_DO_MASK;
422 		if (entry->action & IMA_APPRAISE) {
423 			action |= get_subaction(entry, func);
424 			action &= ~IMA_HASH;
425 			if (ima_fail_unverifiable_sigs)
426 				action |= IMA_FAIL_UNVERIFIABLE_SIGS;
427 		}
428 
429 		if (entry->action & IMA_DO_MASK)
430 			actmask &= ~(entry->action | entry->action << 1);
431 		else
432 			actmask &= ~(entry->action | entry->action >> 1);
433 
434 		if ((pcr) && (entry->flags & IMA_PCR))
435 			*pcr = entry->pcr;
436 
437 		if (!actmask)
438 			break;
439 	}
440 	rcu_read_unlock();
441 
442 	return action;
443 }
444 
445 /*
446  * Initialize the ima_policy_flag variable based on the currently
447  * loaded policy.  Based on this flag, the decision to short circuit
448  * out of a function or not call the function in the first place
449  * can be made earlier.
450  */
451 void ima_update_policy_flag(void)
452 {
453 	struct ima_rule_entry *entry;
454 
455 	list_for_each_entry(entry, ima_rules, list) {
456 		if (entry->action & IMA_DO_MASK)
457 			ima_policy_flag |= entry->action;
458 	}
459 
460 	ima_appraise |= (build_ima_appraise | temp_ima_appraise);
461 	if (!ima_appraise)
462 		ima_policy_flag &= ~IMA_APPRAISE;
463 }
464 
465 static int ima_appraise_flag(enum ima_hooks func)
466 {
467 	if (func == MODULE_CHECK)
468 		return IMA_APPRAISE_MODULES;
469 	else if (func == FIRMWARE_CHECK)
470 		return IMA_APPRAISE_FIRMWARE;
471 	else if (func == POLICY_CHECK)
472 		return IMA_APPRAISE_POLICY;
473 	else if (func == KEXEC_KERNEL_CHECK)
474 		return IMA_APPRAISE_KEXEC;
475 	return 0;
476 }
477 
478 static void add_rules(struct ima_rule_entry *entries, int count,
479 		      enum policy_rule_list policy_rule)
480 {
481 	int i = 0;
482 
483 	for (i = 0; i < count; i++) {
484 		struct ima_rule_entry *entry;
485 
486 		if (policy_rule & IMA_DEFAULT_POLICY)
487 			list_add_tail(&entries[i].list, &ima_default_rules);
488 
489 		if (policy_rule & IMA_CUSTOM_POLICY) {
490 			entry = kmemdup(&entries[i], sizeof(*entry),
491 					GFP_KERNEL);
492 			if (!entry)
493 				continue;
494 
495 			list_add_tail(&entry->list, &ima_policy_rules);
496 		}
497 		if (entries[i].action == APPRAISE) {
498 			temp_ima_appraise |= ima_appraise_flag(entries[i].func);
499 			if (entries[i].func == POLICY_CHECK)
500 				temp_ima_appraise |= IMA_APPRAISE_POLICY;
501 		}
502 	}
503 }
504 
505 static int ima_parse_rule(char *rule, struct ima_rule_entry *entry);
506 
507 static int __init ima_init_arch_policy(void)
508 {
509 	const char * const *arch_rules;
510 	const char * const *rules;
511 	int arch_entries = 0;
512 	int i = 0;
513 
514 	arch_rules = arch_get_ima_policy();
515 	if (!arch_rules)
516 		return arch_entries;
517 
518 	/* Get number of rules */
519 	for (rules = arch_rules; *rules != NULL; rules++)
520 		arch_entries++;
521 
522 	arch_policy_entry = kcalloc(arch_entries + 1,
523 				    sizeof(*arch_policy_entry), GFP_KERNEL);
524 	if (!arch_policy_entry)
525 		return 0;
526 
527 	/* Convert each policy string rules to struct ima_rule_entry format */
528 	for (rules = arch_rules, i = 0; *rules != NULL; rules++) {
529 		char rule[255];
530 		int result;
531 
532 		result = strlcpy(rule, *rules, sizeof(rule));
533 
534 		INIT_LIST_HEAD(&arch_policy_entry[i].list);
535 		result = ima_parse_rule(rule, &arch_policy_entry[i]);
536 		if (result) {
537 			pr_warn("Skipping unknown architecture policy rule: %s\n",
538 				rule);
539 			memset(&arch_policy_entry[i], 0,
540 			       sizeof(*arch_policy_entry));
541 			continue;
542 		}
543 		i++;
544 	}
545 	return i;
546 }
547 
548 /**
549  * ima_init_policy - initialize the default measure rules.
550  *
551  * ima_rules points to either the ima_default_rules or the
552  * the new ima_policy_rules.
553  */
554 void __init ima_init_policy(void)
555 {
556 	int build_appraise_entries, arch_entries;
557 
558 	/* if !ima_policy, we load NO default rules */
559 	if (ima_policy)
560 		add_rules(dont_measure_rules, ARRAY_SIZE(dont_measure_rules),
561 			  IMA_DEFAULT_POLICY);
562 
563 	switch (ima_policy) {
564 	case ORIGINAL_TCB:
565 		add_rules(original_measurement_rules,
566 			  ARRAY_SIZE(original_measurement_rules),
567 			  IMA_DEFAULT_POLICY);
568 		break;
569 	case DEFAULT_TCB:
570 		add_rules(default_measurement_rules,
571 			  ARRAY_SIZE(default_measurement_rules),
572 			  IMA_DEFAULT_POLICY);
573 	default:
574 		break;
575 	}
576 
577 	/*
578 	 * Based on runtime secure boot flags, insert arch specific measurement
579 	 * and appraise rules requiring file signatures for both the initial
580 	 * and custom policies, prior to other appraise rules.
581 	 * (Highest priority)
582 	 */
583 	arch_entries = ima_init_arch_policy();
584 	if (!arch_entries)
585 		pr_info("No architecture policies found\n");
586 	else
587 		add_rules(arch_policy_entry, arch_entries,
588 			  IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY);
589 
590 	/*
591 	 * Insert the builtin "secure_boot" policy rules requiring file
592 	 * signatures, prior to other appraise rules.
593 	 */
594 	if (ima_use_secure_boot)
595 		add_rules(secure_boot_rules, ARRAY_SIZE(secure_boot_rules),
596 			  IMA_DEFAULT_POLICY);
597 
598 	/*
599 	 * Insert the build time appraise rules requiring file signatures
600 	 * for both the initial and custom policies, prior to other appraise
601 	 * rules. As the secure boot rules includes all of the build time
602 	 * rules, include either one or the other set of rules, but not both.
603 	 */
604 	build_appraise_entries = ARRAY_SIZE(build_appraise_rules);
605 	if (build_appraise_entries) {
606 		if (ima_use_secure_boot)
607 			add_rules(build_appraise_rules, build_appraise_entries,
608 				  IMA_CUSTOM_POLICY);
609 		else
610 			add_rules(build_appraise_rules, build_appraise_entries,
611 				  IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY);
612 	}
613 
614 	if (ima_use_appraise_tcb)
615 		add_rules(default_appraise_rules,
616 			  ARRAY_SIZE(default_appraise_rules),
617 			  IMA_DEFAULT_POLICY);
618 
619 	ima_rules = &ima_default_rules;
620 	ima_update_policy_flag();
621 }
622 
623 /* Make sure we have a valid policy, at least containing some rules. */
624 int ima_check_policy(void)
625 {
626 	if (list_empty(&ima_temp_rules))
627 		return -EINVAL;
628 	return 0;
629 }
630 
631 /**
632  * ima_update_policy - update default_rules with new measure rules
633  *
634  * Called on file .release to update the default rules with a complete new
635  * policy.  What we do here is to splice ima_policy_rules and ima_temp_rules so
636  * they make a queue.  The policy may be updated multiple times and this is the
637  * RCU updater.
638  *
639  * Policy rules are never deleted so ima_policy_flag gets zeroed only once when
640  * we switch from the default policy to user defined.
641  */
642 void ima_update_policy(void)
643 {
644 	struct list_head *policy = &ima_policy_rules;
645 
646 	list_splice_tail_init_rcu(&ima_temp_rules, policy, synchronize_rcu);
647 
648 	if (ima_rules != policy) {
649 		ima_policy_flag = 0;
650 		ima_rules = policy;
651 
652 		/*
653 		 * IMA architecture specific policy rules are specified
654 		 * as strings and converted to an array of ima_entry_rules
655 		 * on boot.  After loading a custom policy, free the
656 		 * architecture specific rules stored as an array.
657 		 */
658 		kfree(arch_policy_entry);
659 	}
660 	ima_update_policy_flag();
661 }
662 
663 /* Keep the enumeration in sync with the policy_tokens! */
664 enum {
665 	Opt_measure, Opt_dont_measure,
666 	Opt_appraise, Opt_dont_appraise,
667 	Opt_audit, Opt_hash, Opt_dont_hash,
668 	Opt_obj_user, Opt_obj_role, Opt_obj_type,
669 	Opt_subj_user, Opt_subj_role, Opt_subj_type,
670 	Opt_func, Opt_mask, Opt_fsmagic, Opt_fsname,
671 	Opt_fsuuid, Opt_uid_eq, Opt_euid_eq, Opt_fowner_eq,
672 	Opt_uid_gt, Opt_euid_gt, Opt_fowner_gt,
673 	Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
674 	Opt_appraise_type, Opt_permit_directio,
675 	Opt_pcr, Opt_err
676 };
677 
678 static const match_table_t policy_tokens = {
679 	{Opt_measure, "measure"},
680 	{Opt_dont_measure, "dont_measure"},
681 	{Opt_appraise, "appraise"},
682 	{Opt_dont_appraise, "dont_appraise"},
683 	{Opt_audit, "audit"},
684 	{Opt_hash, "hash"},
685 	{Opt_dont_hash, "dont_hash"},
686 	{Opt_obj_user, "obj_user=%s"},
687 	{Opt_obj_role, "obj_role=%s"},
688 	{Opt_obj_type, "obj_type=%s"},
689 	{Opt_subj_user, "subj_user=%s"},
690 	{Opt_subj_role, "subj_role=%s"},
691 	{Opt_subj_type, "subj_type=%s"},
692 	{Opt_func, "func=%s"},
693 	{Opt_mask, "mask=%s"},
694 	{Opt_fsmagic, "fsmagic=%s"},
695 	{Opt_fsname, "fsname=%s"},
696 	{Opt_fsuuid, "fsuuid=%s"},
697 	{Opt_uid_eq, "uid=%s"},
698 	{Opt_euid_eq, "euid=%s"},
699 	{Opt_fowner_eq, "fowner=%s"},
700 	{Opt_uid_gt, "uid>%s"},
701 	{Opt_euid_gt, "euid>%s"},
702 	{Opt_fowner_gt, "fowner>%s"},
703 	{Opt_uid_lt, "uid<%s"},
704 	{Opt_euid_lt, "euid<%s"},
705 	{Opt_fowner_lt, "fowner<%s"},
706 	{Opt_appraise_type, "appraise_type=%s"},
707 	{Opt_permit_directio, "permit_directio"},
708 	{Opt_pcr, "pcr=%s"},
709 	{Opt_err, NULL}
710 };
711 
712 static int ima_lsm_rule_init(struct ima_rule_entry *entry,
713 			     substring_t *args, int lsm_rule, int audit_type)
714 {
715 	int result;
716 
717 	if (entry->lsm[lsm_rule].rule)
718 		return -EINVAL;
719 
720 	entry->lsm[lsm_rule].args_p = match_strdup(args);
721 	if (!entry->lsm[lsm_rule].args_p)
722 		return -ENOMEM;
723 
724 	entry->lsm[lsm_rule].type = audit_type;
725 	result = security_filter_rule_init(entry->lsm[lsm_rule].type,
726 					   Audit_equal,
727 					   entry->lsm[lsm_rule].args_p,
728 					   &entry->lsm[lsm_rule].rule);
729 	if (!entry->lsm[lsm_rule].rule) {
730 		kfree(entry->lsm[lsm_rule].args_p);
731 		return -EINVAL;
732 	}
733 
734 	return result;
735 }
736 
737 static void ima_log_string_op(struct audit_buffer *ab, char *key, char *value,
738 			      bool (*rule_operator)(kuid_t, kuid_t))
739 {
740 	if (!ab)
741 		return;
742 
743 	if (rule_operator == &uid_gt)
744 		audit_log_format(ab, "%s>", key);
745 	else if (rule_operator == &uid_lt)
746 		audit_log_format(ab, "%s<", key);
747 	else
748 		audit_log_format(ab, "%s=", key);
749 	audit_log_format(ab, "%s ", value);
750 }
751 static void ima_log_string(struct audit_buffer *ab, char *key, char *value)
752 {
753 	ima_log_string_op(ab, key, value, NULL);
754 }
755 
756 static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
757 {
758 	struct audit_buffer *ab;
759 	char *from;
760 	char *p;
761 	bool uid_token;
762 	int result = 0;
763 
764 	ab = integrity_audit_log_start(audit_context(), GFP_KERNEL,
765 				       AUDIT_INTEGRITY_POLICY_RULE);
766 
767 	entry->uid = INVALID_UID;
768 	entry->fowner = INVALID_UID;
769 	entry->uid_op = &uid_eq;
770 	entry->fowner_op = &uid_eq;
771 	entry->action = UNKNOWN;
772 	while ((p = strsep(&rule, " \t")) != NULL) {
773 		substring_t args[MAX_OPT_ARGS];
774 		int token;
775 		unsigned long lnum;
776 
777 		if (result < 0)
778 			break;
779 		if ((*p == '\0') || (*p == ' ') || (*p == '\t'))
780 			continue;
781 		token = match_token(p, policy_tokens, args);
782 		switch (token) {
783 		case Opt_measure:
784 			ima_log_string(ab, "action", "measure");
785 
786 			if (entry->action != UNKNOWN)
787 				result = -EINVAL;
788 
789 			entry->action = MEASURE;
790 			break;
791 		case Opt_dont_measure:
792 			ima_log_string(ab, "action", "dont_measure");
793 
794 			if (entry->action != UNKNOWN)
795 				result = -EINVAL;
796 
797 			entry->action = DONT_MEASURE;
798 			break;
799 		case Opt_appraise:
800 			ima_log_string(ab, "action", "appraise");
801 
802 			if (entry->action != UNKNOWN)
803 				result = -EINVAL;
804 
805 			entry->action = APPRAISE;
806 			break;
807 		case Opt_dont_appraise:
808 			ima_log_string(ab, "action", "dont_appraise");
809 
810 			if (entry->action != UNKNOWN)
811 				result = -EINVAL;
812 
813 			entry->action = DONT_APPRAISE;
814 			break;
815 		case Opt_audit:
816 			ima_log_string(ab, "action", "audit");
817 
818 			if (entry->action != UNKNOWN)
819 				result = -EINVAL;
820 
821 			entry->action = AUDIT;
822 			break;
823 		case Opt_hash:
824 			ima_log_string(ab, "action", "hash");
825 
826 			if (entry->action != UNKNOWN)
827 				result = -EINVAL;
828 
829 			entry->action = HASH;
830 			break;
831 		case Opt_dont_hash:
832 			ima_log_string(ab, "action", "dont_hash");
833 
834 			if (entry->action != UNKNOWN)
835 				result = -EINVAL;
836 
837 			entry->action = DONT_HASH;
838 			break;
839 		case Opt_func:
840 			ima_log_string(ab, "func", args[0].from);
841 
842 			if (entry->func)
843 				result = -EINVAL;
844 
845 			if (strcmp(args[0].from, "FILE_CHECK") == 0)
846 				entry->func = FILE_CHECK;
847 			/* PATH_CHECK is for backwards compat */
848 			else if (strcmp(args[0].from, "PATH_CHECK") == 0)
849 				entry->func = FILE_CHECK;
850 			else if (strcmp(args[0].from, "MODULE_CHECK") == 0)
851 				entry->func = MODULE_CHECK;
852 			else if (strcmp(args[0].from, "FIRMWARE_CHECK") == 0)
853 				entry->func = FIRMWARE_CHECK;
854 			else if ((strcmp(args[0].from, "FILE_MMAP") == 0)
855 				|| (strcmp(args[0].from, "MMAP_CHECK") == 0))
856 				entry->func = MMAP_CHECK;
857 			else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
858 				entry->func = BPRM_CHECK;
859 			else if (strcmp(args[0].from, "CREDS_CHECK") == 0)
860 				entry->func = CREDS_CHECK;
861 			else if (strcmp(args[0].from, "KEXEC_KERNEL_CHECK") ==
862 				 0)
863 				entry->func = KEXEC_KERNEL_CHECK;
864 			else if (strcmp(args[0].from, "KEXEC_INITRAMFS_CHECK")
865 				 == 0)
866 				entry->func = KEXEC_INITRAMFS_CHECK;
867 			else if (strcmp(args[0].from, "POLICY_CHECK") == 0)
868 				entry->func = POLICY_CHECK;
869 			else
870 				result = -EINVAL;
871 			if (!result)
872 				entry->flags |= IMA_FUNC;
873 			break;
874 		case Opt_mask:
875 			ima_log_string(ab, "mask", args[0].from);
876 
877 			if (entry->mask)
878 				result = -EINVAL;
879 
880 			from = args[0].from;
881 			if (*from == '^')
882 				from++;
883 
884 			if ((strcmp(from, "MAY_EXEC")) == 0)
885 				entry->mask = MAY_EXEC;
886 			else if (strcmp(from, "MAY_WRITE") == 0)
887 				entry->mask = MAY_WRITE;
888 			else if (strcmp(from, "MAY_READ") == 0)
889 				entry->mask = MAY_READ;
890 			else if (strcmp(from, "MAY_APPEND") == 0)
891 				entry->mask = MAY_APPEND;
892 			else
893 				result = -EINVAL;
894 			if (!result)
895 				entry->flags |= (*args[0].from == '^')
896 				     ? IMA_INMASK : IMA_MASK;
897 			break;
898 		case Opt_fsmagic:
899 			ima_log_string(ab, "fsmagic", args[0].from);
900 
901 			if (entry->fsmagic) {
902 				result = -EINVAL;
903 				break;
904 			}
905 
906 			result = kstrtoul(args[0].from, 16, &entry->fsmagic);
907 			if (!result)
908 				entry->flags |= IMA_FSMAGIC;
909 			break;
910 		case Opt_fsname:
911 			ima_log_string(ab, "fsname", args[0].from);
912 
913 			entry->fsname = kstrdup(args[0].from, GFP_KERNEL);
914 			if (!entry->fsname) {
915 				result = -ENOMEM;
916 				break;
917 			}
918 			result = 0;
919 			entry->flags |= IMA_FSNAME;
920 			break;
921 		case Opt_fsuuid:
922 			ima_log_string(ab, "fsuuid", args[0].from);
923 
924 			if (!uuid_is_null(&entry->fsuuid)) {
925 				result = -EINVAL;
926 				break;
927 			}
928 
929 			result = uuid_parse(args[0].from, &entry->fsuuid);
930 			if (!result)
931 				entry->flags |= IMA_FSUUID;
932 			break;
933 		case Opt_uid_gt:
934 		case Opt_euid_gt:
935 			entry->uid_op = &uid_gt;
936 			/* fall through */
937 		case Opt_uid_lt:
938 		case Opt_euid_lt:
939 			if ((token == Opt_uid_lt) || (token == Opt_euid_lt))
940 				entry->uid_op = &uid_lt;
941 			/* fall through */
942 		case Opt_uid_eq:
943 		case Opt_euid_eq:
944 			uid_token = (token == Opt_uid_eq) ||
945 				    (token == Opt_uid_gt) ||
946 				    (token == Opt_uid_lt);
947 
948 			ima_log_string_op(ab, uid_token ? "uid" : "euid",
949 					  args[0].from, entry->uid_op);
950 
951 			if (uid_valid(entry->uid)) {
952 				result = -EINVAL;
953 				break;
954 			}
955 
956 			result = kstrtoul(args[0].from, 10, &lnum);
957 			if (!result) {
958 				entry->uid = make_kuid(current_user_ns(),
959 						       (uid_t) lnum);
960 				if (!uid_valid(entry->uid) ||
961 				    (uid_t)lnum != lnum)
962 					result = -EINVAL;
963 				else
964 					entry->flags |= uid_token
965 					    ? IMA_UID : IMA_EUID;
966 			}
967 			break;
968 		case Opt_fowner_gt:
969 			entry->fowner_op = &uid_gt;
970 			/* fall through */
971 		case Opt_fowner_lt:
972 			if (token == Opt_fowner_lt)
973 				entry->fowner_op = &uid_lt;
974 			/* fall through */
975 		case Opt_fowner_eq:
976 			ima_log_string_op(ab, "fowner", args[0].from,
977 					  entry->fowner_op);
978 
979 			if (uid_valid(entry->fowner)) {
980 				result = -EINVAL;
981 				break;
982 			}
983 
984 			result = kstrtoul(args[0].from, 10, &lnum);
985 			if (!result) {
986 				entry->fowner = make_kuid(current_user_ns(), (uid_t)lnum);
987 				if (!uid_valid(entry->fowner) || (((uid_t)lnum) != lnum))
988 					result = -EINVAL;
989 				else
990 					entry->flags |= IMA_FOWNER;
991 			}
992 			break;
993 		case Opt_obj_user:
994 			ima_log_string(ab, "obj_user", args[0].from);
995 			result = ima_lsm_rule_init(entry, args,
996 						   LSM_OBJ_USER,
997 						   AUDIT_OBJ_USER);
998 			break;
999 		case Opt_obj_role:
1000 			ima_log_string(ab, "obj_role", args[0].from);
1001 			result = ima_lsm_rule_init(entry, args,
1002 						   LSM_OBJ_ROLE,
1003 						   AUDIT_OBJ_ROLE);
1004 			break;
1005 		case Opt_obj_type:
1006 			ima_log_string(ab, "obj_type", args[0].from);
1007 			result = ima_lsm_rule_init(entry, args,
1008 						   LSM_OBJ_TYPE,
1009 						   AUDIT_OBJ_TYPE);
1010 			break;
1011 		case Opt_subj_user:
1012 			ima_log_string(ab, "subj_user", args[0].from);
1013 			result = ima_lsm_rule_init(entry, args,
1014 						   LSM_SUBJ_USER,
1015 						   AUDIT_SUBJ_USER);
1016 			break;
1017 		case Opt_subj_role:
1018 			ima_log_string(ab, "subj_role", args[0].from);
1019 			result = ima_lsm_rule_init(entry, args,
1020 						   LSM_SUBJ_ROLE,
1021 						   AUDIT_SUBJ_ROLE);
1022 			break;
1023 		case Opt_subj_type:
1024 			ima_log_string(ab, "subj_type", args[0].from);
1025 			result = ima_lsm_rule_init(entry, args,
1026 						   LSM_SUBJ_TYPE,
1027 						   AUDIT_SUBJ_TYPE);
1028 			break;
1029 		case Opt_appraise_type:
1030 			if (entry->action != APPRAISE) {
1031 				result = -EINVAL;
1032 				break;
1033 			}
1034 
1035 			ima_log_string(ab, "appraise_type", args[0].from);
1036 			if ((strcmp(args[0].from, "imasig")) == 0)
1037 				entry->flags |= IMA_DIGSIG_REQUIRED;
1038 			else
1039 				result = -EINVAL;
1040 			break;
1041 		case Opt_permit_directio:
1042 			entry->flags |= IMA_PERMIT_DIRECTIO;
1043 			break;
1044 		case Opt_pcr:
1045 			if (entry->action != MEASURE) {
1046 				result = -EINVAL;
1047 				break;
1048 			}
1049 			ima_log_string(ab, "pcr", args[0].from);
1050 
1051 			result = kstrtoint(args[0].from, 10, &entry->pcr);
1052 			if (result || INVALID_PCR(entry->pcr))
1053 				result = -EINVAL;
1054 			else
1055 				entry->flags |= IMA_PCR;
1056 
1057 			break;
1058 		case Opt_err:
1059 			ima_log_string(ab, "UNKNOWN", p);
1060 			result = -EINVAL;
1061 			break;
1062 		}
1063 	}
1064 	if (!result && (entry->action == UNKNOWN))
1065 		result = -EINVAL;
1066 	else if (entry->action == APPRAISE)
1067 		temp_ima_appraise |= ima_appraise_flag(entry->func);
1068 
1069 	audit_log_format(ab, "res=%d", !result);
1070 	audit_log_end(ab);
1071 	return result;
1072 }
1073 
1074 /**
1075  * ima_parse_add_rule - add a rule to ima_policy_rules
1076  * @rule - ima measurement policy rule
1077  *
1078  * Avoid locking by allowing just one writer at a time in ima_write_policy()
1079  * Returns the length of the rule parsed, an error code on failure
1080  */
1081 ssize_t ima_parse_add_rule(char *rule)
1082 {
1083 	static const char op[] = "update_policy";
1084 	char *p;
1085 	struct ima_rule_entry *entry;
1086 	ssize_t result, len;
1087 	int audit_info = 0;
1088 
1089 	p = strsep(&rule, "\n");
1090 	len = strlen(p) + 1;
1091 	p += strspn(p, " \t");
1092 
1093 	if (*p == '#' || *p == '\0')
1094 		return len;
1095 
1096 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1097 	if (!entry) {
1098 		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
1099 				    NULL, op, "-ENOMEM", -ENOMEM, audit_info);
1100 		return -ENOMEM;
1101 	}
1102 
1103 	INIT_LIST_HEAD(&entry->list);
1104 
1105 	result = ima_parse_rule(p, entry);
1106 	if (result) {
1107 		kfree(entry);
1108 		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
1109 				    NULL, op, "invalid-policy", result,
1110 				    audit_info);
1111 		return result;
1112 	}
1113 
1114 	list_add_tail(&entry->list, &ima_temp_rules);
1115 
1116 	return len;
1117 }
1118 
1119 /**
1120  * ima_delete_rules() called to cleanup invalid in-flight policy.
1121  * We don't need locking as we operate on the temp list, which is
1122  * different from the active one.  There is also only one user of
1123  * ima_delete_rules() at a time.
1124  */
1125 void ima_delete_rules(void)
1126 {
1127 	struct ima_rule_entry *entry, *tmp;
1128 	int i;
1129 
1130 	temp_ima_appraise = 0;
1131 	list_for_each_entry_safe(entry, tmp, &ima_temp_rules, list) {
1132 		for (i = 0; i < MAX_LSM_RULES; i++)
1133 			kfree(entry->lsm[i].args_p);
1134 
1135 		list_del(&entry->list);
1136 		kfree(entry);
1137 	}
1138 }
1139 
1140 #ifdef	CONFIG_IMA_READ_POLICY
1141 enum {
1142 	mask_exec = 0, mask_write, mask_read, mask_append
1143 };
1144 
1145 static const char *const mask_tokens[] = {
1146 	"^MAY_EXEC",
1147 	"^MAY_WRITE",
1148 	"^MAY_READ",
1149 	"^MAY_APPEND"
1150 };
1151 
1152 #define __ima_hook_stringify(str)	(#str),
1153 
1154 static const char *const func_tokens[] = {
1155 	__ima_hooks(__ima_hook_stringify)
1156 };
1157 
1158 void *ima_policy_start(struct seq_file *m, loff_t *pos)
1159 {
1160 	loff_t l = *pos;
1161 	struct ima_rule_entry *entry;
1162 
1163 	rcu_read_lock();
1164 	list_for_each_entry_rcu(entry, ima_rules, list) {
1165 		if (!l--) {
1166 			rcu_read_unlock();
1167 			return entry;
1168 		}
1169 	}
1170 	rcu_read_unlock();
1171 	return NULL;
1172 }
1173 
1174 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos)
1175 {
1176 	struct ima_rule_entry *entry = v;
1177 
1178 	rcu_read_lock();
1179 	entry = list_entry_rcu(entry->list.next, struct ima_rule_entry, list);
1180 	rcu_read_unlock();
1181 	(*pos)++;
1182 
1183 	return (&entry->list == ima_rules) ? NULL : entry;
1184 }
1185 
1186 void ima_policy_stop(struct seq_file *m, void *v)
1187 {
1188 }
1189 
1190 #define pt(token)	policy_tokens[token].pattern
1191 #define mt(token)	mask_tokens[token]
1192 
1193 /*
1194  * policy_func_show - display the ima_hooks policy rule
1195  */
1196 static void policy_func_show(struct seq_file *m, enum ima_hooks func)
1197 {
1198 	if (func > 0 && func < MAX_CHECK)
1199 		seq_printf(m, "func=%s ", func_tokens[func]);
1200 	else
1201 		seq_printf(m, "func=%d ", func);
1202 }
1203 
1204 int ima_policy_show(struct seq_file *m, void *v)
1205 {
1206 	struct ima_rule_entry *entry = v;
1207 	int i;
1208 	char tbuf[64] = {0,};
1209 	int offset = 0;
1210 
1211 	rcu_read_lock();
1212 
1213 	if (entry->action & MEASURE)
1214 		seq_puts(m, pt(Opt_measure));
1215 	if (entry->action & DONT_MEASURE)
1216 		seq_puts(m, pt(Opt_dont_measure));
1217 	if (entry->action & APPRAISE)
1218 		seq_puts(m, pt(Opt_appraise));
1219 	if (entry->action & DONT_APPRAISE)
1220 		seq_puts(m, pt(Opt_dont_appraise));
1221 	if (entry->action & AUDIT)
1222 		seq_puts(m, pt(Opt_audit));
1223 	if (entry->action & HASH)
1224 		seq_puts(m, pt(Opt_hash));
1225 	if (entry->action & DONT_HASH)
1226 		seq_puts(m, pt(Opt_dont_hash));
1227 
1228 	seq_puts(m, " ");
1229 
1230 	if (entry->flags & IMA_FUNC)
1231 		policy_func_show(m, entry->func);
1232 
1233 	if ((entry->flags & IMA_MASK) || (entry->flags & IMA_INMASK)) {
1234 		if (entry->flags & IMA_MASK)
1235 			offset = 1;
1236 		if (entry->mask & MAY_EXEC)
1237 			seq_printf(m, pt(Opt_mask), mt(mask_exec) + offset);
1238 		if (entry->mask & MAY_WRITE)
1239 			seq_printf(m, pt(Opt_mask), mt(mask_write) + offset);
1240 		if (entry->mask & MAY_READ)
1241 			seq_printf(m, pt(Opt_mask), mt(mask_read) + offset);
1242 		if (entry->mask & MAY_APPEND)
1243 			seq_printf(m, pt(Opt_mask), mt(mask_append) + offset);
1244 		seq_puts(m, " ");
1245 	}
1246 
1247 	if (entry->flags & IMA_FSMAGIC) {
1248 		snprintf(tbuf, sizeof(tbuf), "0x%lx", entry->fsmagic);
1249 		seq_printf(m, pt(Opt_fsmagic), tbuf);
1250 		seq_puts(m, " ");
1251 	}
1252 
1253 	if (entry->flags & IMA_FSNAME) {
1254 		snprintf(tbuf, sizeof(tbuf), "%s", entry->fsname);
1255 		seq_printf(m, pt(Opt_fsname), tbuf);
1256 		seq_puts(m, " ");
1257 	}
1258 
1259 	if (entry->flags & IMA_PCR) {
1260 		snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
1261 		seq_printf(m, pt(Opt_pcr), tbuf);
1262 		seq_puts(m, " ");
1263 	}
1264 
1265 	if (entry->flags & IMA_FSUUID) {
1266 		seq_printf(m, "fsuuid=%pU", &entry->fsuuid);
1267 		seq_puts(m, " ");
1268 	}
1269 
1270 	if (entry->flags & IMA_UID) {
1271 		snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->uid));
1272 		if (entry->uid_op == &uid_gt)
1273 			seq_printf(m, pt(Opt_uid_gt), tbuf);
1274 		else if (entry->uid_op == &uid_lt)
1275 			seq_printf(m, pt(Opt_uid_lt), tbuf);
1276 		else
1277 			seq_printf(m, pt(Opt_uid_eq), tbuf);
1278 		seq_puts(m, " ");
1279 	}
1280 
1281 	if (entry->flags & IMA_EUID) {
1282 		snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->uid));
1283 		if (entry->uid_op == &uid_gt)
1284 			seq_printf(m, pt(Opt_euid_gt), tbuf);
1285 		else if (entry->uid_op == &uid_lt)
1286 			seq_printf(m, pt(Opt_euid_lt), tbuf);
1287 		else
1288 			seq_printf(m, pt(Opt_euid_eq), tbuf);
1289 		seq_puts(m, " ");
1290 	}
1291 
1292 	if (entry->flags & IMA_FOWNER) {
1293 		snprintf(tbuf, sizeof(tbuf), "%d", __kuid_val(entry->fowner));
1294 		if (entry->fowner_op == &uid_gt)
1295 			seq_printf(m, pt(Opt_fowner_gt), tbuf);
1296 		else if (entry->fowner_op == &uid_lt)
1297 			seq_printf(m, pt(Opt_fowner_lt), tbuf);
1298 		else
1299 			seq_printf(m, pt(Opt_fowner_eq), tbuf);
1300 		seq_puts(m, " ");
1301 	}
1302 
1303 	for (i = 0; i < MAX_LSM_RULES; i++) {
1304 		if (entry->lsm[i].rule) {
1305 			switch (i) {
1306 			case LSM_OBJ_USER:
1307 				seq_printf(m, pt(Opt_obj_user),
1308 					   (char *)entry->lsm[i].args_p);
1309 				break;
1310 			case LSM_OBJ_ROLE:
1311 				seq_printf(m, pt(Opt_obj_role),
1312 					   (char *)entry->lsm[i].args_p);
1313 				break;
1314 			case LSM_OBJ_TYPE:
1315 				seq_printf(m, pt(Opt_obj_type),
1316 					   (char *)entry->lsm[i].args_p);
1317 				break;
1318 			case LSM_SUBJ_USER:
1319 				seq_printf(m, pt(Opt_subj_user),
1320 					   (char *)entry->lsm[i].args_p);
1321 				break;
1322 			case LSM_SUBJ_ROLE:
1323 				seq_printf(m, pt(Opt_subj_role),
1324 					   (char *)entry->lsm[i].args_p);
1325 				break;
1326 			case LSM_SUBJ_TYPE:
1327 				seq_printf(m, pt(Opt_subj_type),
1328 					   (char *)entry->lsm[i].args_p);
1329 				break;
1330 			}
1331 		}
1332 	}
1333 	if (entry->flags & IMA_DIGSIG_REQUIRED)
1334 		seq_puts(m, "appraise_type=imasig ");
1335 	if (entry->flags & IMA_PERMIT_DIRECTIO)
1336 		seq_puts(m, "permit_directio ");
1337 	rcu_read_unlock();
1338 	seq_puts(m, "\n");
1339 	return 0;
1340 }
1341 #endif	/* CONFIG_IMA_READ_POLICY */
1342