summaryrefslogtreecommitdiffstats
path: root/security/tomoyo/number_group.c
blob: eca20d6f4e8b9e633f412e80688a6a99850ed3ef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/*
 * 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_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_group *tomoyo_get_number_group(const char *group_name)
{
	struct tomoyo_group *entry = NULL;
	struct tomoyo_group *group = NULL;
	const struct tomoyo_path_info *saved_group_name;
	int error = -ENOMEM;
	if (!tomoyo_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;
}

static bool tomoyo_same_number_group(const struct tomoyo_acl_head *a,
				     const struct tomoyo_acl_head *b)
{
	return !memcmp(&container_of(a, struct tomoyo_number_group,
				     head)->number,
		       &container_of(b, struct tomoyo_number_group,
				     head)->number,
		       sizeof(container_of(a,
					   struct tomoyo_number_group,
					   head)->number));
}

/**
 * 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_group *group;
	struct tomoyo_number_group e = { };
	int error;
	char *w[2];
	if (!tomoyo_tokenize(data, w, sizeof(w)))
		return -EINVAL;
	if (w[1][0] == '@' || !tomoyo_parse_number_union(w[1], &e.number) ||
	    e.number.values[0] > e.number.values[1])
		return -EINVAL;
	group = tomoyo_get_number_group(w[0]);
	if (!group)
		return -ENOMEM;
	error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
				     &group->member_list,
				     tomoyo_same_number_group);
	tomoyo_put_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_group *group;
		const char *name;
		group = list_entry(gpos, struct tomoyo_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
				= list_entry(mpos,
					     struct tomoyo_number_group,
					     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_group *group)
{
	struct tomoyo_number_group *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;
}
OpenPOWER on IntegriCloud