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