xref: /openbmc/linux/security/tomoyo/group.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * security/tomoyo/group.c
3  *
4  * Copyright (C) 2005-2010  NTT DATA CORPORATION
5  */
6 
7 #include <linux/slab.h>
8 #include "common.h"
9 
10 static bool tomoyo_same_path_group(const struct tomoyo_acl_head *a,
11 				const struct tomoyo_acl_head *b)
12 {
13 	return container_of(a, struct tomoyo_path_group, head)->member_name ==
14 		container_of(b, struct tomoyo_path_group, head)->member_name;
15 }
16 
17 static bool tomoyo_same_number_group(const struct tomoyo_acl_head *a,
18 				  const struct tomoyo_acl_head *b)
19 {
20 	return !memcmp(&container_of(a, struct tomoyo_number_group, head)
21 		       ->number,
22 		       &container_of(b, struct tomoyo_number_group, head)
23 		       ->number,
24 		       sizeof(container_of(a, struct tomoyo_number_group, head)
25 			      ->number));
26 }
27 
28 /**
29  * tomoyo_write_group - Write "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
30  *
31  * @data:      String to parse.
32  * @is_delete: True if it is a delete request.
33  * @type:      Type of this group.
34  *
35  * Returns 0 on success, negative value otherwise.
36  */
37 int tomoyo_write_group(char *data, const bool is_delete, const u8 type)
38 {
39 	struct tomoyo_group *group;
40 	struct list_head *member;
41 	char *w[2];
42 	int error = -EINVAL;
43 	if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[1][0])
44 		return -EINVAL;
45 	group = tomoyo_get_group(w[0], type);
46 	if (!group)
47 		return -ENOMEM;
48 	member = &group->member_list;
49 	if (type == TOMOYO_PATH_GROUP) {
50 		struct tomoyo_path_group e = { };
51 		e.member_name = tomoyo_get_name(w[1]);
52 		if (!e.member_name) {
53 			error = -ENOMEM;
54 			goto out;
55 		}
56 		error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
57 					     member, tomoyo_same_path_group);
58 		tomoyo_put_name(e.member_name);
59 	} else if (type == TOMOYO_NUMBER_GROUP) {
60 		struct tomoyo_number_group e = { };
61 		if (w[1][0] == '@'
62 		    || !tomoyo_parse_number_union(w[1], &e.number)
63 		    || e.number.values[0] > e.number.values[1])
64 			goto out;
65 		error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
66 					     member, tomoyo_same_number_group);
67 		/*
68 		 * tomoyo_put_number_union() is not needed because
69 		 * w[1][0] != '@'.
70 		 */
71 	}
72  out:
73 	tomoyo_put_group(group);
74 	return error;
75 }
76 
77 /**
78  * tomoyo_path_matches_group - Check whether the given pathname matches members of the given pathname group.
79  *
80  * @pathname:        The name of pathname.
81  * @group:           Pointer to "struct tomoyo_path_group".
82  *
83  * Returns matched member's pathname if @pathname matches pathnames in @group,
84  * NULL otherwise.
85  *
86  * Caller holds tomoyo_read_lock().
87  */
88 const struct tomoyo_path_info *
89 tomoyo_path_matches_group(const struct tomoyo_path_info *pathname,
90 			  const struct tomoyo_group *group)
91 {
92 	struct tomoyo_path_group *member;
93 	list_for_each_entry_rcu(member, &group->member_list, head.list) {
94 		if (member->head.is_deleted)
95 			continue;
96 		if (!tomoyo_path_matches_pattern(pathname, member->member_name))
97 			continue;
98 		return member->member_name;
99 	}
100 	return NULL;
101 }
102 
103 /**
104  * tomoyo_number_matches_group - Check whether the given number matches members of the given number group.
105  *
106  * @min:   Min number.
107  * @max:   Max number.
108  * @group: Pointer to "struct tomoyo_number_group".
109  *
110  * Returns true if @min and @max partially overlaps @group, false otherwise.
111  *
112  * Caller holds tomoyo_read_lock().
113  */
114 bool tomoyo_number_matches_group(const unsigned long min,
115 				 const unsigned long max,
116 				 const struct tomoyo_group *group)
117 {
118 	struct tomoyo_number_group *member;
119 	bool matched = false;
120 	list_for_each_entry_rcu(member, &group->member_list, head.list) {
121 		if (member->head.is_deleted)
122 			continue;
123 		if (min > member->number.values[1] ||
124 		    max < member->number.values[0])
125 			continue;
126 		matched = true;
127 		break;
128 	}
129 	return matched;
130 }
131