[deliverable/linux.git] / security / integrity / ima / ima_policy.c

/*
 * Copyright (C) 2008 IBM Corporation
 * Author: Mimi Zohar <zohar@us.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 2 of the License.
 *
 * ima_policy.c
 * 	- initialize default measure policy rules
 *
 */
#include <linux/module.h>
#include <linux/list.h>
#include <linux/security.h>
#include <linux/magic.h>
#include <linux/parser.h>

#include "ima.h"

/* flags definitions */
#define IMA_FUNC 	0x0001
#define IMA_MASK 	0x0002
#define IMA_FSMAGIC	0x0004
#define IMA_UID		0x0008

enum ima_action { UNKNOWN = -1, DONT_MEASURE = 0, MEASURE };

#define MAX_LSM_RULES 6
enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
	LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
};

struct ima_measure_rule_entry {
	struct list_head list;
	enum ima_action action;
	unsigned int flags;
	enum ima_hooks func;
	int mask;
	unsigned long fsmagic;
	uid_t uid;
	struct {
		void *rule;	/* LSM file metadata specific */
		int type;	/* audit type */
	} lsm[MAX_LSM_RULES];
};

/* Without LSM specific knowledge, the default policy can only be
 * written in terms of .action, .func, .mask, .fsmagic, and .uid
 */
static struct ima_measure_rule_entry default_rules[] = {
	{.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
	{.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
	{.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
	{.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC},
	{.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC},
	{.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC},
	{.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC,
	 .flags = IMA_FUNC | IMA_MASK},
	{.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC,
	 .flags = IMA_FUNC | IMA_MASK},
};

static LIST_HEAD(measure_default_rules);
static LIST_HEAD(measure_policy_rules);
static struct list_head *ima_measure;

static DEFINE_MUTEX(ima_measure_mutex);

/**
 * ima_match_rules - determine whether an inode matches the measure rule.
 * @rule: a pointer to a rule
 * @inode: a pointer to an inode
 * @func: LIM hook identifier
 * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
 *
 * Returns true on rule match, false on failure.
 */
static bool ima_match_rules(struct ima_measure_rule_entry *rule,
			    struct inode *inode, enum ima_hooks func, int mask)
{
	struct task_struct *tsk = current;
	int i;

	if ((rule->flags & IMA_FUNC) && rule->func != func)
		return false;
	if ((rule->flags & IMA_MASK) && rule->mask != mask)
		return false;
	if ((rule->flags & IMA_FSMAGIC)
	    && rule->fsmagic != inode->i_sb->s_magic)
		return false;
	if ((rule->flags & IMA_UID) && rule->uid != tsk->cred->uid)
		return false;
	for (i = 0; i < MAX_LSM_RULES; i++) {
		int rc = 0;
		u32 osid, sid;

		if (!rule->lsm[i].rule)
			continue;

		switch (i) {
		case LSM_OBJ_USER:
		case LSM_OBJ_ROLE:
		case LSM_OBJ_TYPE:
			security_inode_getsecid(inode, &osid);
			rc = security_filter_rule_match(osid,
							rule->lsm[i].type,
							Audit_equal,
							rule->lsm[i].rule,
							NULL);
			break;
		case LSM_SUBJ_USER:
		case LSM_SUBJ_ROLE:
		case LSM_SUBJ_TYPE:
			security_task_getsecid(tsk, &sid);
			rc = security_filter_rule_match(sid,
							rule->lsm[i].type,
							Audit_equal,
							rule->lsm[i].rule,
							NULL);
		default:
			break;
		}
		if (!rc)
			return false;
	}
	return true;
}

/**
 * ima_match_policy - decision based on LSM and other conditions
 * @inode: pointer to an inode for which the policy decision is being made
 * @func: IMA hook identifier
 * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
 *
 * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
 * conditions.
 *
 * (There is no need for locking when walking the policy list,
 * as elements in the list are never deleted, nor does the list
 * change.)
 */
int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask)
{
	struct ima_measure_rule_entry *entry;

	list_for_each_entry(entry, ima_measure, list) {
		bool rc;

		rc = ima_match_rules(entry, inode, func, mask);
		if (rc)
			return entry->action;
	}
	return 0;
}

/**
 * ima_init_policy - initialize the default measure rules.
 *
 * ima_measure points to either the measure_default_rules or the
 * the new measure_policy_rules.
 */
void ima_init_policy(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(default_rules); i++)
		list_add_tail(&default_rules[i].list, &measure_default_rules);
	ima_measure = &measure_default_rules;
}

/**
 * ima_update_policy - update default_rules with new measure rules
 *
 * Called on file .release to update the default rules with a complete new
 * policy.  Once updated, the policy is locked, no additional rules can be
 * added to the policy.
 */
void ima_update_policy(void)
{
	const char *op = "policy_update";
	const char *cause = "already exists";
	int result = 1;
	int audit_info = 0;

	if (ima_measure == &measure_default_rules) {
		ima_measure = &measure_policy_rules;
		cause = "complete";
		result = 0;
	}
	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
			    NULL, op, cause, result, audit_info);
}

enum {
	Opt_err = -1,
	Opt_measure = 1, Opt_dont_measure,
	Opt_obj_user, Opt_obj_role, Opt_obj_type,
	Opt_subj_user, Opt_subj_role, Opt_subj_type,
	Opt_func, Opt_mask, Opt_fsmagic, Opt_uid
};

static match_table_t policy_tokens = {
	{Opt_measure, "measure"},
	{Opt_dont_measure, "dont_measure"},
	{Opt_obj_user, "obj_user=%s"},
	{Opt_obj_role, "obj_role=%s"},
	{Opt_obj_type, "obj_type=%s"},
	{Opt_subj_user, "subj_user=%s"},
	{Opt_subj_role, "subj_role=%s"},
	{Opt_subj_type, "subj_type=%s"},
	{Opt_func, "func=%s"},
	{Opt_mask, "mask=%s"},
	{Opt_fsmagic, "fsmagic=%s"},
	{Opt_uid, "uid=%s"},
	{Opt_err, NULL}
};

static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry,
			     char *args, int lsm_rule, int audit_type)
{
	int result;

	entry->lsm[lsm_rule].type = audit_type;
	result = security_filter_rule_init(entry->lsm[lsm_rule].type,
					   Audit_equal, args,
					   &entry->lsm[lsm_rule].rule);
	return result;
}

static int ima_parse_rule(char *rule, struct ima_measure_rule_entry *entry)
{
	struct audit_buffer *ab;
	char *p;
	int result = 0;

	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);

	entry->action = -1;
	while ((p = strsep(&rule, " \n")) != NULL) {
		substring_t args[MAX_OPT_ARGS];
		int token;
		unsigned long lnum;

		if (result < 0)
			break;
		if (!*p)
			continue;
		token = match_token(p, policy_tokens, args);
		switch (token) {
		case Opt_measure:
			audit_log_format(ab, "%s ", "measure");
			entry->action = MEASURE;
			break;
		case Opt_dont_measure:
			audit_log_format(ab, "%s ", "dont_measure");
			entry->action = DONT_MEASURE;
			break;
		case Opt_func:
			audit_log_format(ab, "func=%s ", args[0].from);
			if (strcmp(args[0].from, "PATH_CHECK") == 0)
				entry->func = PATH_CHECK;
			else if (strcmp(args[0].from, "FILE_MMAP") == 0)
				entry->func = FILE_MMAP;
			else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
				entry->func = BPRM_CHECK;
			else
				result = -EINVAL;
			if (!result)
				entry->flags |= IMA_FUNC;
			break;
		case Opt_mask:
			audit_log_format(ab, "mask=%s ", args[0].from);
			if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
				entry->mask = MAY_EXEC;
			else if (strcmp(args[0].from, "MAY_WRITE") == 0)
				entry->mask = MAY_WRITE;
			else if (strcmp(args[0].from, "MAY_READ") == 0)
				entry->mask = MAY_READ;
			else if (strcmp(args[0].from, "MAY_APPEND") == 0)
				entry->mask = MAY_APPEND;
			else
				result = -EINVAL;
			if (!result)
				entry->flags |= IMA_MASK;
			break;
		case Opt_fsmagic:
			audit_log_format(ab, "fsmagic=%s ", args[0].from);
			result = strict_strtoul(args[0].from, 16,
						&entry->fsmagic);
			if (!result)
				entry->flags |= IMA_FSMAGIC;
			break;
		case Opt_uid:
			audit_log_format(ab, "uid=%s ", args[0].from);
			result = strict_strtoul(args[0].from, 10, &lnum);
			if (!result) {
				entry->uid = (uid_t) lnum;
				if (entry->uid != lnum)
					result = -EINVAL;
				else
					entry->flags |= IMA_UID;
			}
			break;
		case Opt_obj_user:
			audit_log_format(ab, "obj_user=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_OBJ_USER,
						   AUDIT_OBJ_USER);
			break;
		case Opt_obj_role:
			audit_log_format(ab, "obj_role=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_OBJ_ROLE,
						   AUDIT_OBJ_ROLE);
			break;
		case Opt_obj_type:
			audit_log_format(ab, "obj_type=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_OBJ_TYPE,
						   AUDIT_OBJ_TYPE);
			break;
		case Opt_subj_user:
			audit_log_format(ab, "subj_user=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_SUBJ_USER,
						   AUDIT_SUBJ_USER);
			break;
		case Opt_subj_role:
			audit_log_format(ab, "subj_role=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_SUBJ_ROLE,
						   AUDIT_SUBJ_ROLE);
			break;
		case Opt_subj_type:
			audit_log_format(ab, "subj_type=%s ", args[0].from);
			result = ima_lsm_rule_init(entry, args[0].from,
						   LSM_SUBJ_TYPE,
						   AUDIT_SUBJ_TYPE);
			break;
		case Opt_err:
			audit_log_format(ab, "UNKNOWN=%s ", p);
			break;
		}
	}
	if (entry->action == UNKNOWN)
		result = -EINVAL;

	audit_log_format(ab, "res=%d", !result ? 0 : 1);
	audit_log_end(ab);
	return result;
}

/**
 * ima_parse_add_rule - add a rule to measure_policy_rules
 * @rule - ima measurement policy rule
 *
 * Uses a mutex to protect the policy list from multiple concurrent writers.
 * Returns 0 on success, an error code on failure.
 */
int ima_parse_add_rule(char *rule)
{
	const char *op = "update_policy";
	struct ima_measure_rule_entry *entry;
	int result = 0;
	int audit_info = 0;

	/* Prevent installed policy from changing */
	if (ima_measure != &measure_default_rules) {
		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
				    NULL, op, "already exists",
				    -EACCES, audit_info);
		return -EACCES;
	}

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (!entry) {
		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
				    NULL, op, "-ENOMEM", -ENOMEM, audit_info);
		return -ENOMEM;
	}

	INIT_LIST_HEAD(&entry->list);

	result = ima_parse_rule(rule, entry);
	if (!result) {
		mutex_lock(&ima_measure_mutex);
		list_add_tail(&entry->list, &measure_policy_rules);
		mutex_unlock(&ima_measure_mutex);
	} else {
		kfree(entry);
		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
				    NULL, op, "invalid policy", result,
				    audit_info);
	}
	return result;
}

/* ima_delete_rules called to cleanup invalid policy */
void ima_delete_rules(void)
{
	struct ima_measure_rule_entry *entry, *tmp;

	mutex_lock(&ima_measure_mutex);
	list_for_each_entry_safe(entry, tmp, &measure_policy_rules, list) {
		list_del(&entry->list);
		kfree(entry);
	}
	mutex_unlock(&ima_measure_mutex);
}
Commit	Line	Data
3323eec9 MZ	1	/*
	2	* Copyright (C) 2008 IBM Corporation
	3	* Author: Mimi Zohar <zohar@us.ibm.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation, version 2 of the License.
	8	*
	9	* ima_policy.c
	10	* - initialize default measure policy rules
	11	*
	12	*/
	13	#include <linux/module.h>
	14	#include <linux/list.h>
3323eec9 MZ	15	#include <linux/security.h>
3323eec9 MZ	16	#include <linux/magic.h>
4af4662f	17	#include <linux/parser.h>
3323eec9 MZ	18
	19	#include "ima.h"
	20
	21	/* flags definitions */
	22	#define IMA_FUNC 0x0001
	23	#define IMA_MASK 0x0002
	24	#define IMA_FSMAGIC 0x0004
	25	#define IMA_UID 0x0008
	26
4af4662f MZ	27	enum ima_action { UNKNOWN = -1, DONT_MEASURE = 0, MEASURE };
	28
	29	#define MAX_LSM_RULES 6
	30	enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE,
	31	LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE
	32	};
3323eec9 MZ	33
	34	struct ima_measure_rule_entry {
	35	struct list_head list;
	36	enum ima_action action;
	37	unsigned int flags;
	38	enum ima_hooks func;
	39	int mask;
	40	unsigned long fsmagic;
	41	uid_t uid;
4af4662f MZ	42	struct {
	43	void rule; / LSM file metadata specific */
	44	int type; /* audit type */
	45	} lsm[MAX_LSM_RULES];
3323eec9 MZ	46	};
3323eec9 MZ	47
4af4662f MZ	48	/* Without LSM specific knowledge, the default policy can only be
	49	* written in terms of .action, .func, .mask, .fsmagic, and .uid
	50	*/
3323eec9	51	static struct ima_measure_rule_entry default_rules[] = {
75834fc3	52	{.action = DONT_MEASURE,.fsmagic = PROC_SUPER_MAGIC,.flags = IMA_FSMAGIC},
3323eec9 MZ	53	{.action = DONT_MEASURE,.fsmagic = SYSFS_MAGIC,.flags = IMA_FSMAGIC},
	54	{.action = DONT_MEASURE,.fsmagic = DEBUGFS_MAGIC,.flags = IMA_FSMAGIC},
	55	{.action = DONT_MEASURE,.fsmagic = TMPFS_MAGIC,.flags = IMA_FSMAGIC},
75834fc3 EP	56	{.action = DONT_MEASURE,.fsmagic = SECURITYFS_MAGIC,.flags = IMA_FSMAGIC},
75834fc3 EP	57	{.action = DONT_MEASURE,.fsmagic = SELINUX_MAGIC,.flags = IMA_FSMAGIC},
3323eec9 MZ	58	{.action = MEASURE,.func = FILE_MMAP,.mask = MAY_EXEC,
	59	.flags = IMA_FUNC \| IMA_MASK},
	60	{.action = MEASURE,.func = BPRM_CHECK,.mask = MAY_EXEC,
	61	.flags = IMA_FUNC \| IMA_MASK},
3323eec9 MZ	62	};
	63
	64	static LIST_HEAD(measure_default_rules);
4af4662f	65	static LIST_HEAD(measure_policy_rules);
3323eec9 MZ	66	static struct list_head *ima_measure;
3323eec9 MZ	67
4af4662f MZ	68	static DEFINE_MUTEX(ima_measure_mutex);
4af4662f MZ	69
3323eec9 MZ	70	/**
	71	* ima_match_rules - determine whether an inode matches the measure rule.
	72	* @rule: a pointer to a rule
	73	* @inode: a pointer to an inode
	74	* @func: LIM hook identifier
	75	* @mask: requested action (MAY_READ \| MAY_WRITE \| MAY_APPEND \| MAY_EXEC)
	76	*
	77	* Returns true on rule match, false on failure.
	78	*/
	79	static bool ima_match_rules(struct ima_measure_rule_entry *rule,
	80	struct inode *inode, enum ima_hooks func, int mask)
	81	{
	82	struct task_struct *tsk = current;
4af4662f	83	int i;
3323eec9 MZ	84
	85	if ((rule->flags & IMA_FUNC) && rule->func != func)
	86	return false;
	87	if ((rule->flags & IMA_MASK) && rule->mask != mask)
	88	return false;
	89	if ((rule->flags & IMA_FSMAGIC)
	90	&& rule->fsmagic != inode->i_sb->s_magic)
	91	return false;
	92	if ((rule->flags & IMA_UID) && rule->uid != tsk->cred->uid)
	93	return false;
4af4662f	94	for (i = 0; i < MAX_LSM_RULES; i++) {
53fc0e22	95	int rc = 0;
4af4662f MZ	96	u32 osid, sid;
	97
	98	if (!rule->lsm[i].rule)
	99	continue;
	100
	101	switch (i) {
	102	case LSM_OBJ_USER:
	103	case LSM_OBJ_ROLE:
	104	case LSM_OBJ_TYPE:
	105	security_inode_getsecid(inode, &osid);
	106	rc = security_filter_rule_match(osid,
	107	rule->lsm[i].type,
53fc0e22	108	Audit_equal,
4af4662f MZ	109	rule->lsm[i].rule,
	110	NULL);
	111	break;
	112	case LSM_SUBJ_USER:
	113	case LSM_SUBJ_ROLE:
	114	case LSM_SUBJ_TYPE:
	115	security_task_getsecid(tsk, &sid);
	116	rc = security_filter_rule_match(sid,
	117	rule->lsm[i].type,
53fc0e22	118	Audit_equal,
4af4662f MZ	119	rule->lsm[i].rule,
	120	NULL);
	121	default:
	122	break;
	123	}
	124	if (!rc)
	125	return false;
	126	}
3323eec9 MZ	127	return true;
	128	}
	129
	130	/**
	131	* ima_match_policy - decision based on LSM and other conditions
	132	* @inode: pointer to an inode for which the policy decision is being made
	133	* @func: IMA hook identifier
	134	* @mask: requested action (MAY_READ \| MAY_WRITE \| MAY_APPEND \| MAY_EXEC)
	135	*
	136	* Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
	137	* conditions.
	138	*
	139	* (There is no need for locking when walking the policy list,
	140	* as elements in the list are never deleted, nor does the list
	141	* change.)
	142	*/
	143	int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask)
	144	{
	145	struct ima_measure_rule_entry *entry;
	146
	147	list_for_each_entry(entry, ima_measure, list) {
	148	bool rc;
	149
	150	rc = ima_match_rules(entry, inode, func, mask);
	151	if (rc)
	152	return entry->action;
	153	}
	154	return 0;
	155	}
	156
	157	/**
	158	* ima_init_policy - initialize the default measure rules.
	159	*
3323eec9	160	* ima_measure points to either the measure_default_rules or the
4af4662f	161	* the new measure_policy_rules.
3323eec9 MZ	162	*/
	163	void ima_init_policy(void)
	164	{
	165	int i;
	166
	167	for (i = 0; i < ARRAY_SIZE(default_rules); i++)
	168	list_add_tail(&default_rules[i].list, &measure_default_rules);
	169	ima_measure = &measure_default_rules;
	170	}
4af4662f MZ	171
	172	/**
	173	* ima_update_policy - update default_rules with new measure rules
	174	*
	175	* Called on file .release to update the default rules with a complete new
	176	* policy. Once updated, the policy is locked, no additional rules can be
	177	* added to the policy.
	178	*/
	179	void ima_update_policy(void)
	180	{
	181	const char *op = "policy_update";
	182	const char *cause = "already exists";
	183	int result = 1;
	184	int audit_info = 0;
	185
	186	if (ima_measure == &measure_default_rules) {
	187	ima_measure = &measure_policy_rules;
	188	cause = "complete";
	189	result = 0;
	190	}
	191	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
	192	NULL, op, cause, result, audit_info);
	193	}
	194
	195	enum {
	196	Opt_err = -1,
	197	Opt_measure = 1, Opt_dont_measure,
	198	Opt_obj_user, Opt_obj_role, Opt_obj_type,
	199	Opt_subj_user, Opt_subj_role, Opt_subj_type,
	200	Opt_func, Opt_mask, Opt_fsmagic, Opt_uid
	201	};
	202
	203	static match_table_t policy_tokens = {
	204	{Opt_measure, "measure"},
	205	{Opt_dont_measure, "dont_measure"},
	206	{Opt_obj_user, "obj_user=%s"},
	207	{Opt_obj_role, "obj_role=%s"},
	208	{Opt_obj_type, "obj_type=%s"},
	209	{Opt_subj_user, "subj_user=%s"},
	210	{Opt_subj_role, "subj_role=%s"},
	211	{Opt_subj_type, "subj_type=%s"},
	212	{Opt_func, "func=%s"},
	213	{Opt_mask, "mask=%s"},
	214	{Opt_fsmagic, "fsmagic=%s"},
	215	{Opt_uid, "uid=%s"},
	216	{Opt_err, NULL}
	217	};
	218
	219	static int ima_lsm_rule_init(struct ima_measure_rule_entry *entry,
	220	char *args, int lsm_rule, int audit_type)
	221	{
	222	int result;
	223
	224	entry->lsm[lsm_rule].type = audit_type;
	225	result = security_filter_rule_init(entry->lsm[lsm_rule].type,
53fc0e22	226	Audit_equal, args,
4af4662f MZ	227	&entry->lsm[lsm_rule].rule);
	228	return result;
	229	}
	230
	231	static int ima_parse_rule(char rule, struct ima_measure_rule_entry entry)
	232	{
	233	struct audit_buffer *ab;
	234	char *p;
	235	int result = 0;
	236
523979ad	237	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_INTEGRITY_RULE);
4af4662f MZ	238
	239	entry->action = -1;
	240	while ((p = strsep(&rule, " \n")) != NULL) {
	241	substring_t args[MAX_OPT_ARGS];
	242	int token;
	243	unsigned long lnum;
	244
	245	if (result < 0)
	246	break;
	247	if (!*p)
	248	continue;
	249	token = match_token(p, policy_tokens, args);
	250	switch (token) {
	251	case Opt_measure:
	252	audit_log_format(ab, "%s ", "measure");
	253	entry->action = MEASURE;
	254	break;
	255	case Opt_dont_measure:
	256	audit_log_format(ab, "%s ", "dont_measure");
	257	entry->action = DONT_MEASURE;
	258	break;
	259	case Opt_func:
	260	audit_log_format(ab, "func=%s ", args[0].from);
	261	if (strcmp(args[0].from, "PATH_CHECK") == 0)
	262	entry->func = PATH_CHECK;
	263	else if (strcmp(args[0].from, "FILE_MMAP") == 0)
	264	entry->func = FILE_MMAP;
	265	else if (strcmp(args[0].from, "BPRM_CHECK") == 0)
	266	entry->func = BPRM_CHECK;
	267	else
	268	result = -EINVAL;
	269	if (!result)
	270	entry->flags \|= IMA_FUNC;
	271	break;
	272	case Opt_mask:
	273	audit_log_format(ab, "mask=%s ", args[0].from);
	274	if ((strcmp(args[0].from, "MAY_EXEC")) == 0)
	275	entry->mask = MAY_EXEC;
	276	else if (strcmp(args[0].from, "MAY_WRITE") == 0)
	277	entry->mask = MAY_WRITE;
	278	else if (strcmp(args[0].from, "MAY_READ") == 0)
	279	entry->mask = MAY_READ;
	280	else if (strcmp(args[0].from, "MAY_APPEND") == 0)
	281	entry->mask = MAY_APPEND;
	282	else
	283	result = -EINVAL;
	284	if (!result)
	285	entry->flags \|= IMA_MASK;
	286	break;
	287	case Opt_fsmagic:
	288	audit_log_format(ab, "fsmagic=%s ", args[0].from);
	289	result = strict_strtoul(args[0].from, 16,
	290	&entry->fsmagic);
	291	if (!result)
	292	entry->flags \|= IMA_FSMAGIC;
	293	break;
	294	case Opt_uid:
	295	audit_log_format(ab, "uid=%s ", args[0].from);
	296	result = strict_strtoul(args[0].from, 10, &lnum);
	297	if (!result) {
	298	entry->uid = (uid_t) lnum;
	299	if (entry->uid != lnum)
	300	result = -EINVAL;
	301	else
302	entry->flags \|= IMA_UID;
303	}
304	break;
305	case Opt_obj_user:
306	audit_log_format(ab, "obj_user=%s ", args[0].from);
307	result = ima_lsm_rule_init(entry, args[0].from,
308	LSM_OBJ_USER,
309	AUDIT_OBJ_USER);
310	break;
311	case Opt_obj_role:
312	audit_log_format(ab, "obj_role=%s ", args[0].from);
313	result = ima_lsm_rule_init(entry, args[0].from,
314	LSM_OBJ_ROLE,
315	AUDIT_OBJ_ROLE);
316	break;
317	case Opt_obj_type:
318	audit_log_format(ab, "obj_type=%s ", args[0].from);
319	result = ima_lsm_rule_init(entry, args[0].from,
320	LSM_OBJ_TYPE,
321	AUDIT_OBJ_TYPE);
322	break;
323	case Opt_subj_user:
324	audit_log_format(ab, "subj_user=%s ", args[0].from);
325	result = ima_lsm_rule_init(entry, args[0].from,
326	LSM_SUBJ_USER,
327	AUDIT_SUBJ_USER);
328	break;
329	case Opt_subj_role:
330	audit_log_format(ab, "subj_role=%s ", args[0].from);
331	result = ima_lsm_rule_init(entry, args[0].from,
332	LSM_SUBJ_ROLE,
333	AUDIT_SUBJ_ROLE);
334	break;
335	case Opt_subj_type:
336	audit_log_format(ab, "subj_type=%s ", args[0].from);
337	result = ima_lsm_rule_init(entry, args[0].from,
338	LSM_SUBJ_TYPE,
339	AUDIT_SUBJ_TYPE);
340	break;
341	case Opt_err:
523979ad	342	audit_log_format(ab, "UNKNOWN=%s ", p);
4af4662f MZ	343	break;
	344	}
	345	}
	346	if (entry->action == UNKNOWN)
	347	result = -EINVAL;
	348
523979ad	349	audit_log_format(ab, "res=%d", !result ? 0 : 1);
4af4662f MZ	350	audit_log_end(ab);
	351	return result;
	352	}
	353
	354	/**
	355	* ima_parse_add_rule - add a rule to measure_policy_rules
	356	* @rule - ima measurement policy rule
	357	*
	358	* Uses a mutex to protect the policy list from multiple concurrent writers.
	359	* Returns 0 on success, an error code on failure.
	360	*/
	361	int ima_parse_add_rule(char *rule)
	362	{
523979ad	363	const char *op = "update_policy";
4af4662f MZ	364	struct ima_measure_rule_entry *entry;
	365	int result = 0;
	366	int audit_info = 0;
	367
	368	/* Prevent installed policy from changing */
	369	if (ima_measure != &measure_default_rules) {
	370	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
	371	NULL, op, "already exists",
	372	-EACCES, audit_info);
	373	return -EACCES;
	374	}
	375
	376	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	377	if (!entry) {
	378	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
	379	NULL, op, "-ENOMEM", -ENOMEM, audit_info);
	380	return -ENOMEM;
	381	}
	382
	383	INIT_LIST_HEAD(&entry->list);
	384
	385	result = ima_parse_rule(rule, entry);
	386	if (!result) {
	387	mutex_lock(&ima_measure_mutex);
	388	list_add_tail(&entry->list, &measure_policy_rules);
	389	mutex_unlock(&ima_measure_mutex);
523979ad	390	} else {
4af4662f	391	kfree(entry);
523979ad MZ	392	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL,
	393	NULL, op, "invalid policy", result,
	394	audit_info);
	395	}
4af4662f MZ	396	return result;
	397	}
	398
	399	/* ima_delete_rules called to cleanup invalid policy */
64c61d80	400	void ima_delete_rules(void)
4af4662f MZ	401	{
	402	struct ima_measure_rule_entry entry, tmp;
	403
	404	mutex_lock(&ima_measure_mutex);
	405	list_for_each_entry_safe(entry, tmp, &measure_policy_rules, list) {
	406	list_del(&entry->list);
	407	kfree(entry);
	408	}
	409	mutex_unlock(&ima_measure_mutex);
	410	}