[net-next-2.6.git] / security / tomoyo / number_group.c

/*
 * security/tomoyo/number_group.c
 *
 * Copyright (C) 2005-2009  NTT DATA CORPORATION
 */

#include <linux/slab.h>
#include "common.h"

/* The list for "struct tomoyo_number_group". */
LIST_HEAD(tomoyo_number_group_list);

/**
 * tomoyo_get_number_group - Allocate memory for "struct tomoyo_number_group".
 *
 * @group_name: The name of number group.
 *
 * Returns pointer to "struct tomoyo_number_group" on success,
 * NULL otherwise.
 */
struct tomoyo_number_group *tomoyo_get_number_group(const char *group_name)
{
	struct tomoyo_number_group *entry = NULL;
	struct tomoyo_number_group *group = NULL;
	const struct tomoyo_path_info *saved_group_name;
	int error = -ENOMEM;
	if (!tomoyo_is_correct_word(group_name))
		return NULL;
	saved_group_name = tomoyo_get_name(group_name);
	if (!saved_group_name)
		return NULL;
	entry = kzalloc(sizeof(*entry), GFP_NOFS);
	if (mutex_lock_interruptible(&tomoyo_policy_lock))
		goto out;
	list_for_each_entry_rcu(group, &tomoyo_number_group_list, list) {
		if (saved_group_name != group->group_name)
			continue;
		atomic_inc(&group->users);
		error = 0;
		break;
	}
	if (error && tomoyo_memory_ok(entry)) {
		INIT_LIST_HEAD(&entry->member_list);
		entry->group_name = saved_group_name;
		saved_group_name = NULL;
		atomic_set(&entry->users, 1);
		list_add_tail_rcu(&entry->list, &tomoyo_number_group_list);
		group = entry;
		entry = NULL;
		error = 0;
	}
	mutex_unlock(&tomoyo_policy_lock);
 out:
	tomoyo_put_name(saved_group_name);
	kfree(entry);
	return !error ? group : NULL;
}

/**
 * tomoyo_write_number_group_policy - Write "struct tomoyo_number_group" list.
 *
 * @data:      String to parse.
 * @is_delete: True if it is a delete request.
 *
 * Returns 0 on success, nagative value otherwise.
 */
int tomoyo_write_number_group_policy(char *data, const bool is_delete)
{
	struct tomoyo_number_group *group;
	struct tomoyo_number_group_member e = { };
	struct tomoyo_number_group_member *member;
	int error = is_delete ? -ENOENT : -ENOMEM;
	char *w[2];
	if (!tomoyo_tokenize(data, w, sizeof(w)))
		return -EINVAL;
	if (!tomoyo_parse_number_union(w[1], &e.number))
		return -EINVAL;
	if (e.number.is_group || e.number.values[0] > e.number.values[1]) {
		tomoyo_put_number_union(&e.number);
		return -EINVAL;
	}
	group = tomoyo_get_number_group(w[0]);
	if (!group)
		return -ENOMEM;
	if (mutex_lock_interruptible(&tomoyo_policy_lock))
		goto out;
	list_for_each_entry_rcu(member, &group->member_list, head.list) {
		if (memcmp(&member->number, &e.number, sizeof(e.number)))
			continue;
		member->head.is_deleted = is_delete;
		error = 0;
		break;
	}
	if (!is_delete && error) {
		struct tomoyo_number_group_member *entry =
			tomoyo_commit_ok(&e, sizeof(e));
		if (entry) {
			list_add_tail_rcu(&entry->head.list,
					  &group->member_list);
			error = 0;
		}
	}
	mutex_unlock(&tomoyo_policy_lock);
 out:
	tomoyo_put_number_group(group);
	return error;
}

/**
 * tomoyo_read_number_group_policy - Read "struct tomoyo_number_group" list.
 *
 * @head: Pointer to "struct tomoyo_io_buffer".
 *
 * Returns true on success, false otherwise.
 *
 * Caller holds tomoyo_read_lock().
 */
bool tomoyo_read_number_group_policy(struct tomoyo_io_buffer *head)
{
	struct list_head *gpos;
	struct list_head *mpos;
	list_for_each_cookie(gpos, head->read_var1, &tomoyo_number_group_list) {
		struct tomoyo_number_group *group;
		const char *name;
		group = list_entry(gpos, struct tomoyo_number_group, list);
		name = group->group_name->name;
		list_for_each_cookie(mpos, head->read_var2,
				     &group->member_list) {
			int pos;
			const struct tomoyo_number_group_member *member
				= list_entry(mpos,
					     struct tomoyo_number_group_member,
					     head.list);
			if (member->head.is_deleted)
				continue;
			pos = head->read_avail;
			if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_NUMBER_GROUP
					      "%s", name) ||
			    !tomoyo_print_number_union(head, &member->number) ||
			    !tomoyo_io_printf(head, "\n")) {
				head->read_avail = pos;
				return false;
			}
		}
	}
	return true;
}

/**
 * tomoyo_number_matches_group - Check whether the given number matches members of the given number group.
 *
 * @min:   Min number.
 * @max:   Max number.
 * @group: Pointer to "struct tomoyo_number_group".
 *
 * Returns true if @min and @max partially overlaps @group, false otherwise.
 *
 * Caller holds tomoyo_read_lock().
 */
bool tomoyo_number_matches_group(const unsigned long min,
				 const unsigned long max,
				 const struct tomoyo_number_group *group)
{
	struct tomoyo_number_group_member *member;
	bool matched = false;
	list_for_each_entry_rcu(member, &group->member_list, head.list) {
		if (member->head.is_deleted)
			continue;
		if (min > member->number.values[1] ||
		    max < member->number.values[0])
			continue;
		matched = true;
		break;
	}
	return matched;
}
Commit	Line	Data
4c3e9e2d TH	1	/*
	2	* security/tomoyo/number_group.c
	3	*
	4	* Copyright (C) 2005-2009 NTT DATA CORPORATION
	5	*/
	6
	7	#include <linux/slab.h>
	8	#include "common.h"
	9
	10	/* The list for "struct tomoyo_number_group". */
	11	LIST_HEAD(tomoyo_number_group_list);
	12
	13	/**
	14	* tomoyo_get_number_group - Allocate memory for "struct tomoyo_number_group".
	15	*
	16	* @group_name: The name of number group.
	17	*
	18	* Returns pointer to "struct tomoyo_number_group" on success,
	19	* NULL otherwise.
	20	*/
	21	struct tomoyo_number_group tomoyo_get_number_group(const char group_name)
	22	{
	23	struct tomoyo_number_group *entry = NULL;
	24	struct tomoyo_number_group *group = NULL;
	25	const struct tomoyo_path_info *saved_group_name;
	26	int error = -ENOMEM;
3f629636	27	if (!tomoyo_is_correct_word(group_name))
4c3e9e2d TH	28	return NULL;
	29	saved_group_name = tomoyo_get_name(group_name);
	30	if (!saved_group_name)
	31	return NULL;
	32	entry = kzalloc(sizeof(*entry), GFP_NOFS);
	33	if (mutex_lock_interruptible(&tomoyo_policy_lock))
	34	goto out;
	35	list_for_each_entry_rcu(group, &tomoyo_number_group_list, list) {
	36	if (saved_group_name != group->group_name)
	37	continue;
	38	atomic_inc(&group->users);
	39	error = 0;
	40	break;
	41	}
	42	if (error && tomoyo_memory_ok(entry)) {
	43	INIT_LIST_HEAD(&entry->member_list);
	44	entry->group_name = saved_group_name;
	45	saved_group_name = NULL;
	46	atomic_set(&entry->users, 1);
	47	list_add_tail_rcu(&entry->list, &tomoyo_number_group_list);
	48	group = entry;
	49	entry = NULL;
	50	error = 0;
	51	}
	52	mutex_unlock(&tomoyo_policy_lock);
	53	out:
	54	tomoyo_put_name(saved_group_name);
	55	kfree(entry);
	56	return !error ? group : NULL;
	57	}
	58
	59	/**
	60	* tomoyo_write_number_group_policy - Write "struct tomoyo_number_group" list.
	61	*
	62	* @data: String to parse.
	63	* @is_delete: True if it is a delete request.
	64	*
	65	* Returns 0 on success, nagative value otherwise.
	66	*/
	67	int tomoyo_write_number_group_policy(char *data, const bool is_delete)
	68	{
	69	struct tomoyo_number_group *group;
	70	struct tomoyo_number_group_member e = { };
	71	struct tomoyo_number_group_member *member;
	72	int error = is_delete ? -ENOENT : -ENOMEM;
	73	char *w[2];
	74	if (!tomoyo_tokenize(data, w, sizeof(w)))
	75	return -EINVAL;
	76	if (!tomoyo_parse_number_union(w[1], &e.number))
	77	return -EINVAL;
	78	if (e.number.is_group \|\| e.number.values[0] > e.number.values[1]) {
	79	tomoyo_put_number_union(&e.number);
	80	return -EINVAL;
	81	}
	82	group = tomoyo_get_number_group(w[0]);
	83	if (!group)
	84	return -ENOMEM;
	85	if (mutex_lock_interruptible(&tomoyo_policy_lock))
	86	goto out;
82e0f001	87	list_for_each_entry_rcu(member, &group->member_list, head.list) {
4c3e9e2d TH	88	if (memcmp(&member->number, &e.number, sizeof(e.number)))
4c3e9e2d TH	89	continue;
82e0f001	90	member->head.is_deleted = is_delete;
4c3e9e2d TH	91	error = 0;
	92	break;
	93	}
	94	if (!is_delete && error) {
	95	struct tomoyo_number_group_member *entry =
	96	tomoyo_commit_ok(&e, sizeof(e));
	97	if (entry) {
82e0f001 TH	98	list_add_tail_rcu(&entry->head.list,
82e0f001 TH	99	&group->member_list);
4c3e9e2d TH	100	error = 0;
	101	}
	102	}
	103	mutex_unlock(&tomoyo_policy_lock);
	104	out:
	105	tomoyo_put_number_group(group);
	106	return error;
	107	}
	108
	109	/**
	110	* tomoyo_read_number_group_policy - Read "struct tomoyo_number_group" list.
	111	*
	112	* @head: Pointer to "struct tomoyo_io_buffer".
	113	*
	114	* Returns true on success, false otherwise.
	115	*
	116	* Caller holds tomoyo_read_lock().
	117	*/
	118	bool tomoyo_read_number_group_policy(struct tomoyo_io_buffer *head)
	119	{
	120	struct list_head *gpos;
	121	struct list_head *mpos;
	122	list_for_each_cookie(gpos, head->read_var1, &tomoyo_number_group_list) {
	123	struct tomoyo_number_group *group;
	124	const char *name;
	125	group = list_entry(gpos, struct tomoyo_number_group, list);
	126	name = group->group_name->name;
	127	list_for_each_cookie(mpos, head->read_var2,
	128	&group->member_list) {
	129	int pos;
	130	const struct tomoyo_number_group_member *member
	131	= list_entry(mpos,
	132	struct tomoyo_number_group_member,
82e0f001 TH	133	head.list);
82e0f001 TH	134	if (member->head.is_deleted)
4c3e9e2d TH	135	continue;
	136	pos = head->read_avail;
	137	if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_NUMBER_GROUP
	138	"%s", name) \|\|
	139	!tomoyo_print_number_union(head, &member->number) \|\|
	140	!tomoyo_io_printf(head, "\n")) {
	141	head->read_avail = pos;
	142	return false;
	143	}
	144	}
	145	}
	146	return true;
	147	}
	148
	149	/**
	150	* tomoyo_number_matches_group - Check whether the given number matches members of the given number group.
	151	*
	152	* @min: Min number.
	153	* @max: Max number.
	154	* @group: Pointer to "struct tomoyo_number_group".
	155	*
	156	* Returns true if @min and @max partially overlaps @group, false otherwise.
	157	*
	158	* Caller holds tomoyo_read_lock().
	159	*/
	160	bool tomoyo_number_matches_group(const unsigned long min,
	161	const unsigned long max,
	162	const struct tomoyo_number_group *group)
	163	{
	164	struct tomoyo_number_group_member *member;
	165	bool matched = false;
82e0f001 TH	166	list_for_each_entry_rcu(member, &group->member_list, head.list) {
82e0f001 TH	167	if (member->head.is_deleted)
4c3e9e2d TH	168	continue;
	169	if (min > member->number.values[1] \|\|
	170	max < member->number.values[0])
	171	continue;
	172	matched = true;
	173	break;
	174	}
	175	return matched;
	176	}