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 __must_hold_shared(&tomoyo_ss) 36 { 37 return tomoyo_supervisor(r, "misc env %s\n", 38 r->param.environ.name->name); 39 } 40 41 /** 42 * tomoyo_env_perm - Check permission for environment variable's name. 43 * 44 * @r: Pointer to "struct tomoyo_request_info". 45 * @env: The name of environment variable. 46 * 47 * Returns 0 on success, negative value otherwise. 48 * 49 * Caller holds tomoyo_read_lock(). 50 */ 51 int tomoyo_env_perm(struct tomoyo_request_info *r, const char *env) 52 { 53 struct tomoyo_path_info environ; 54 int error; 55 56 if (!env || !*env) 57 return 0; 58 environ.name = env; 59 tomoyo_fill_path_info(&environ); 60 r->param_type = TOMOYO_TYPE_ENV_ACL; 61 r->param.environ.name = &environ; 62 do { 63 tomoyo_check_acl(r, tomoyo_check_env_acl); 64 error = tomoyo_audit_env_log(r); 65 } while (error == TOMOYO_RETRY_REQUEST); 66 return error; 67 } 68 69 /** 70 * tomoyo_same_env_acl - Check for duplicated "struct tomoyo_env_acl" entry. 71 * 72 * @a: Pointer to "struct tomoyo_acl_info". 73 * @b: Pointer to "struct tomoyo_acl_info". 74 * 75 * Returns true if @a == @b, false otherwise. 76 */ 77 static bool tomoyo_same_env_acl(const struct tomoyo_acl_info *a, 78 const struct tomoyo_acl_info *b) 79 { 80 const struct tomoyo_env_acl *p1 = container_of(a, typeof(*p1), head); 81 const struct tomoyo_env_acl *p2 = container_of(b, typeof(*p2), head); 82 83 return p1->env == p2->env; 84 } 85 86 /** 87 * tomoyo_write_env - Write "struct tomoyo_env_acl" list. 88 * 89 * @param: Pointer to "struct tomoyo_acl_param". 90 * 91 * Returns 0 on success, negative value otherwise. 92 * 93 * Caller holds tomoyo_read_lock(). 94 */ 95 static int tomoyo_write_env(struct tomoyo_acl_param *param) 96 { 97 struct tomoyo_env_acl e = { .head.type = TOMOYO_TYPE_ENV_ACL }; 98 int error = -ENOMEM; 99 const char *data = tomoyo_read_token(param); 100 101 if (!tomoyo_correct_word(data) || strchr(data, '=')) 102 return -EINVAL; 103 e.env = tomoyo_get_name(data); 104 if (!e.env) 105 return error; 106 error = tomoyo_update_domain(&e.head, sizeof(e), param, 107 tomoyo_same_env_acl, NULL); 108 tomoyo_put_name(e.env); 109 return error; 110 } 111 112 /** 113 * tomoyo_write_misc - Update environment variable list. 114 * 115 * @param: Pointer to "struct tomoyo_acl_param". 116 * 117 * Returns 0 on success, negative value otherwise. 118 */ 119 int tomoyo_write_misc(struct tomoyo_acl_param *param) 120 { 121 if (tomoyo_str_starts(¶m->data, "env ")) 122 return tomoyo_write_env(param); 123 return -EINVAL; 124 } 125