1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * security/tomoyo/environ.c
4 *
5 * Copyright (C) 2005-2011 NTT DATA CORPORATION
6 */
7
8 #include "common.h"
9
10 /**
11 * tomoyo_check_env_acl - Check permission for environment variable's name.
12 *
13 * @r: Pointer to "struct tomoyo_request_info".
14 * @ptr: Pointer to "struct tomoyo_acl_info".
15 *
16 * Returns true if granted, false otherwise.
17 */
18 static bool tomoyo_check_env_acl(struct tomoyo_request_info *r,
19 const struct tomoyo_acl_info *ptr)
20 {
21 const struct tomoyo_env_acl *acl =
22 container_of(ptr, typeof(*acl), head);
23
24 return tomoyo_path_matches_pattern(r->param.environ.name, acl->env);
25 }
26
27 /**
28 * tomoyo_audit_env_log - Audit environment variable name log.
29 *
30 * @r: Pointer to "struct tomoyo_request_info".
31 *
32 * Returns 0 on success, negative value otherwise.
33 */
34 static int tomoyo_audit_env_log(struct tomoyo_request_info *r)
35 {
36 return tomoyo_supervisor(r, "misc env %s\n",
37 r->param.environ.name->name);
38 }
39
40 /**
41 * tomoyo_env_perm - Check permission for environment variable's name.
42 *
43 * @r: Pointer to "struct tomoyo_request_info".
44 * @env: The name of environment variable.
45 *
46 * Returns 0 on success, negative value otherwise.
47 *
48 * Caller holds tomoyo_read_lock().
49 */
50 int tomoyo_env_perm(struct tomoyo_request_info *r, const char *env)
51 {
52 struct tomoyo_path_info environ;
53 int error;
54
55 if (!env || !*env)
56 return 0;
57 environ.name = env;
58 tomoyo_fill_path_info(&environ);
59 r->param_type = TOMOYO_TYPE_ENV_ACL;
60 r->param.environ.name = &environ;
61 do {
62 tomoyo_check_acl(r, tomoyo_check_env_acl);
63 error = tomoyo_audit_env_log(r);
64 } while (error == TOMOYO_RETRY_REQUEST);
65 return error;
66 }
67
68 /**
69 * tomoyo_same_env_acl - Check for duplicated "struct tomoyo_env_acl" entry.
70 *
71 * @a: Pointer to "struct tomoyo_acl_info".
72 * @b: Pointer to "struct tomoyo_acl_info".
73 *
74 * Returns true if @a == @b, false otherwise.
75 */
76 static bool tomoyo_same_env_acl(const struct tomoyo_acl_info *a,
77 const struct tomoyo_acl_info *b)
78 {
79 const struct tomoyo_env_acl *p1 = container_of(a, typeof(*p1), head);
80 const struct tomoyo_env_acl *p2 = container_of(b, typeof(*p2), head);
81
82 return p1->env == p2->env;
83 }
84
85 /**
86 * tomoyo_write_env - Write "struct tomoyo_env_acl" list.
87 *
88 * @param: Pointer to "struct tomoyo_acl_param".
89 *
90 * Returns 0 on success, negative value otherwise.
91 *
92 * Caller holds tomoyo_read_lock().
93 */
94 static int tomoyo_write_env(struct tomoyo_acl_param *param)
95 {
96 struct tomoyo_env_acl e = { .head.type = TOMOYO_TYPE_ENV_ACL };
97 int error = -ENOMEM;
98 const char *data = tomoyo_read_token(param);
99
100 if (!tomoyo_correct_word(data) || strchr(data, '='))
101 return -EINVAL;
102 e.env = tomoyo_get_name(data);
103 if (!e.env)
104 return error;
105 error = tomoyo_update_domain(&e.head, sizeof(e), param,
106 tomoyo_same_env_acl, NULL);
107 tomoyo_put_name(e.env);
108 return error;
109 }
110
111 /**
112 * tomoyo_write_misc - Update environment variable list.
113 *
114 * @param: Pointer to "struct tomoyo_acl_param".
115 *
116 * Returns 0 on success, negative value otherwise.
117 */
118 int tomoyo_write_misc(struct tomoyo_acl_param *param)
119 {
120 if (tomoyo_str_starts(¶m->data, "env "))
121 return tomoyo_write_env(param);
122 return -EINVAL;
123 }
124
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.