/* * security/tomoyo/domain.c * * Implementation of the Domain-Based Mandatory Access Control. * * Copyright (C) 2005-2009 NTT DATA CORPORATION * * Version: 2.2.0 2009/04/01 * */ #include "common.h" #include "tomoyo.h" #include "realpath.h" #include /* Variables definitions.*/ /* The initial domain. */ struct tomoyo_domain_info tomoyo_kernel_domain; /* The list for "struct tomoyo_domain_info". */ LIST_HEAD(tomoyo_domain_list); DECLARE_RWSEM(tomoyo_domain_list_lock); /* Structure for "initialize_domain" and "no_initialize_domain" keyword. */ struct tomoyo_domain_initializer_entry { struct list_head list; const struct tomoyo_path_info *domainname; /* This may be NULL */ const struct tomoyo_path_info *program; bool is_deleted; bool is_not; /* True if this entry is "no_initialize_domain". */ /* True if the domainname is tomoyo_get_last_name(). */ bool is_last_name; }; /* Structure for "keep_domain" and "no_keep_domain" keyword. */ struct tomoyo_domain_keeper_entry { struct list_head list; const struct tomoyo_path_info *domainname; const struct tomoyo_path_info *program; /* This may be NULL */ bool is_deleted; bool is_not; /* True if this entry is "no_keep_domain". */ /* True if the domainname is tomoyo_get_last_name(). */ bool is_last_name; }; /* Structure for "alias" keyword. */ struct tomoyo_alias_entry { struct list_head list; const struct tomoyo_path_info *original_name; const struct tomoyo_path_info *aliased_name; bool is_deleted; }; /** * tomoyo_set_domain_flag - Set or clear domain's attribute flags. * * @domain: Pointer to "struct tomoyo_domain_info". * @is_delete: True if it is a delete request. * @flags: Flags to set or clear. * * Returns nothing. */ void tomoyo_set_domain_flag(struct tomoyo_domain_info *domain, const bool is_delete, const u8 flags) { /* We need to serialize because this is bitfield operation. */ static DEFINE_SPINLOCK(lock); spin_lock(&lock); if (!is_delete) domain->flags |= flags; else domain->flags &= ~flags; spin_unlock(&lock); } /** * tomoyo_get_last_name - Get last component of a domainname. * * @domain: Pointer to "struct tomoyo_domain_info". * * Returns the last component of the domainname. */ const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain) { const char *cp0 = domain->domainname->name; const char *cp1 = strrchr(cp0, ' '); if (cp1) return cp1 + 1; return cp0; } /* The list for "struct tomoyo_domain_initializer_entry". */ static LIST_HEAD(tomoyo_domain_initializer_list); static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock); /** * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list. * * @domainname: The name of domain. May be NULL. * @program: The name of program. * @is_not: True if it is "no_initialize_domain" entry. * @is_delete: True if it is a delete request. * * Returns 0 on success, negative value otherwise. */ static int tomoyo_update_domain_initializer_entry(const char *domainname, const char *program, const bool is_not, const bool is_delete) { struct tomoyo_domain_initializer_entry *new_entry; struct tomoyo_domain_initializer_entry *ptr; const struct tomoyo_path_info *saved_program; const struct tomoyo_path_info *saved_domainname = NULL; int error = -ENOMEM; bool is_last_name = false; if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__)) return -EINVAL; /* No patterns allowed. */ if (domainname) { if (!tomoyo_is_domain_def(domainname) && tomoyo_is_correct_path(domainname, 1, -1, -1, __func__)) is_last_name = true; else if (!tomoyo_is_correct_domain(domainname, __func__)) return -EINVAL; saved_domainname = tomoyo_save_name(domainname); if (!saved_domainname) return -ENOMEM; } saved_program = tomoyo_save_name(program); if (!saved_program) return -ENOMEM; down_write(&tomoyo_domain_initializer_list_lock); list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { if (ptr->is_not != is_not || ptr->domainname != saved_domainname || ptr->program != saved_program) continue; ptr->is_deleted = is_delete; error = 0; goto out; } if (is_delete) { error = -ENOENT; goto out; } new_entry = tomoyo_alloc_element(sizeof(*new_entry)); if (!new_entry) goto out; new_entry->domainname = saved_domainname; new_entry->program = saved_program; new_entry->is_not = is_not; new_entry->is_last_name = is_last_name; list_add_tail(&new_entry->list, &tomoyo_domain_initializer_list); error = 0; out: up_write(&tomoyo_domain_initializer_list_lock); return error; } /** * tomoyo_read_domain_initializer_policy - Read "struct tomoyo_domain_initializer_entry" list. * * @head: Pointer to "struct tomoyo_io_buffer". * * Returns true on success, false otherwise. */ bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head) { struct list_head *pos; bool done = true; down_read(&tomoyo_domain_initializer_list_lock); list_for_each_cookie(pos, head->read_var2, &tomoyo_domain_initializer_list) { const char *no; const char *from = ""; const char *domain = ""; struct tomoyo_domain_initializer_entry *ptr; ptr = list_entry(pos, struct tomoyo_domain_initializer_entry, list); if (ptr->is_deleted) continue; no = ptr->is_not ? "no_" : ""; if (ptr->domainname) { from = " from "; domain = ptr->domainname->name; } if (!tomoyo_io_printf(head, "%s" TOMOYO_KEYWORD_INITIALIZE_DOMAIN "%s%s%s\n", no, ptr->program->name, from, domain)) { done = false; break; } } up_read(&tomoyo_domain_initializer_list_lock); return done; } /** * tomoyo_write_domain_initializer_policy - Write "struct tomoyo_domain_initializer_entry" list. * * @data: String to parse. * @is_not: True if it is "no_initialize_domain" entry. * @is_delete: True if it is a delete request. * * Returns 0 on success, negative value otherwise. */ int tomoyo_write_domain_initializer_policy(char *data, const bool is_not, const bool is_delete) { char *cp = strstr(data, " from "); if (cp) { *cp = '\0'; return tomoyo_update_domain_initializer_entry(cp + 6, data, is_not, is_delete); } return tomoyo_update_domain_initializer_entry(NULL, data, is_not, is_delete); } /** * tomoyo_is_domain_initializer - Check whether the given program causes domainname reinitialization. * * @domainname: The name of domain. * @program: The name of program. * @last_name: The last component of @domainname. * * Returns true if executing @program reinitializes domain transition, * false otherwise. */ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info * domainname, const struct tomoyo_path_info *program, const struct tomoyo_path_info * last_name) { struct tomoyo_domain_initializer_entry *ptr; bool flag = false; down_read(&tomoyo_domain_initializer_list_lock); list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) { if (ptr->is_deleted) continue; if (ptr->domainname) { if (!ptr->is_last_name) { if (ptr->domainname != domainname) continue; } else { if (tomoyo_pathcmp(ptr->domainname, last_name)) continue; } } if (tomoyo_pathcmp(ptr->program, program)) continue; if (ptr->is_not) { flag = false; break; } flag = true; } up_read(&tomoyo_domain_initializer_list_lock); return flag; } /* The list for "struct tomoyo_domain_keeper_entry". */ static LIST_HEAD(tomoyo_domain_keeper_list); static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock); /** * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list. * * @domainname: The name of domain. * @program: The name of program. May be NULL. * @is_not: True if it is "no_keep_domain" entry. * @is_delete: True if it is a delete request. * * Returns 0 on success, negative value otherwise. */ static int tomoyo_update_domain_keeper_entry(const char *domainname, const char *program, const bool is_not, const bool is_delete) { struct tomoyo_domain_keeper_entry *new_entry; struct tomoyo_domain_keeper_entry *ptr; const struct tomoyo_path_info *saved_domainname; const struct tomoyo_path_info *saved_program = NULL; int error = -ENOMEM; bool is_last_name = false; if (!tomoyo_is_domain_def(domainname) && tomoyo_is_correct_path(domainname, 1, -1, -1, __func__)) is_last_name = true; else if (!tomoyo_is_correct_domain(domainname, __func__)) return -EINVAL; if (program) { if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__)) return -EINVAL; saved_program = tomoyo_save_name(program); if (!saved_program) return -ENOMEM; } saved_domainname = tomoyo_save_name(domainname); if (!saved_domainname) return -ENOMEM; down_write(&tomoyo_domain_keeper_list_lock); list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { if (ptr->is_not != is_not || ptr->domainname != saved_domainname || ptr->program != saved_program) continue; ptr->is_deleted = is_delete; error = 0; goto out; } if (is_delete) { error = -ENOENT; goto out; } new_entry = tomoyo_alloc_element(sizeof(*new_entry)); if (!new_entry) goto out; new_entry->domainname = saved_domainname; new_entry->program = saved_program; new_entry->is_not = is_not; new_entry->is_last_name = is_last_name; list_add_tail(&new_entry->list, &tomoyo_domain_keeper_list); error = 0; out: up_write(&tomoyo_domain_keeper_list_lock); return error; } /** * tomoyo_write_domain_keeper_policy - Write "struct tomoyo_domain_keeper_entry" list. * * @data: String to parse. * @is_not: True if it is "no_keep_domain" entry. * @is_delete: True if it is a delete request. * */ int tomoyo_write_domain_keeper_policy(char *data, const bool is_not, const bool is_delete) { char *cp = strstr(data, " from "); if (cp) { *cp = '\0'; return tomoyo_update_domain_keeper_entry(cp + 6, data, is_not, is_delete); } return tomoyo_update_domain_keeper_entry(data, NULL, is_not, is_delete); } /** * tomoyo_read_domain_keeper_policy - Read "struct tomoyo_domain_keeper_entry" list. * * @head: Pointer to "struct tomoyo_io_buffer". * * Returns true on success, false otherwise. */ bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head) { struct list_head *pos; bool done = true; down_read(&tomoyo_domain_keeper_list_lock); list_for_each_cookie(pos, head->read_var2, &tomoyo_domain_keeper_list) { struct tomoyo_domain_keeper_entry *ptr; const char *no; const char *from = ""; const char *program = ""; ptr = list_entry(pos, struct tomoyo_domain_keeper_entry, list); if (ptr->is_deleted) continue; no = ptr->is_not ? "no_" : ""; if (ptr->program) { from = " from "; program = ptr->program->name; } if (!tomoyo_io_printf(head, "%s" TOMOYO_KEYWORD_KEEP_DOMAIN "%s%s%s\n", no, program, from, ptr->domainname->name)) { done = false; break; } } up_read(&tomoyo_domain_keeper_list_lock); return done; } /** * tomoyo_is_domain_keeper - Check whether the given program causes domain transition suppression. * * @domainname: The name of domain. * @program: The name of program. * @last_name: The last component of @domainname. * * Returns true if executing @program supresses domain transition, * false otherwise. */ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname, const struct tomoyo_path_info *program, const struct tomoyo_path_info *last_name) { struct tomoyo_domain_keeper_entry *ptr; bool flag = false; down_read(&tomoyo_domain_keeper_list_lock); list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) { if (ptr->is_deleted) continue; if (!ptr->is_last_name) { if (ptr->domainname != domainname) continue; } else { if (tomoyo_pathcmp(ptr->domainname, last_name)) continue; } if (ptr->program && tomoyo_pathcmp(ptr->program, program)) continue; if (ptr->is_not) { flag = false; break; } flag = true; } up_read(&tomoyo_domain_keeper_list_lock); return flag; } /* The list for "struct tomoyo_alias_entry". */ static LIST_HEAD(tomoyo_alias_list); static DECLARE_RWSEM(tomoyo_alias_list_lock); /** * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list. * * @original_name: The original program's real name. * @aliased_name: The symbolic program's symbolic link's name. * @is_delete: True if it is a delete request. * * Returns 0 on success, negative value otherwise. */ static int tomoyo_update_alias_entry(const char *original_name, const char *aliased_name, const bool is_delete) { struct tomoyo_alias_entry *new_entry; struct tomoyo_alias_entry *ptr; const struct tomoyo_path_info *saved_original_name; const struct tomoyo_path_info *saved_aliased_name; int error = -ENOMEM; if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) || !tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__)) return -EINVAL; /* No patterns allowed. */ saved_original_name = tomoyo_save_name(original_name); saved_aliased_name = tomoyo_save_name(aliased_name); if (!saved_original_name || !saved_aliased_name) return -ENOMEM; down_write(&tomoyo_alias_list_lock); list_for_each_entry(ptr, &tomoyo_alias_list, list) { if (ptr->original_name != saved_original_name || ptr->aliased_name != saved_aliased_name) continue; ptr->is_deleted = is_delete; error = 0; goto out; } if (is_delete) { error = -ENOENT; goto out; } new_entry = tomoyo_alloc_element(sizeof(*new_entry)); if (!new_entry) goto out; new_entry->original_name = saved_original_name; new_entry->aliased_name = saved_aliased_name; list_add_tail(&new_entry->list, &tomoyo_alias_list); error = 0; out: up_write(&tomoyo_alias_list_lock); return error; } /** * tomoyo_read_alias_policy - Read "struct tomoyo_alias_entry" list. * * @head: Pointer to "struct tomoyo_io_buffer". * * Returns true on success, false otherwise. */ bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head) { struct list_head *pos; bool done = true; down_read(&tomoyo_alias_list_lock); list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) { struct tomoyo_alias_entry *ptr; ptr = list_entry(pos, struct tomoyo_alias_entry, list); if (ptr->is_deleted) continue; if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALIAS "%s %s\n", ptr->original_name->name, ptr->aliased_name->name)) { done = false; break; } } up_read(&tomoyo_alias_list_lock); return done; } /** * tomoyo_write_alias_policy - Write "struct tomoyo_alias_entry" list. * * @data: String to parse. * @is_delete: True if it is a delete request. * * Returns 0 on success, negative value otherwise. */ int tomoyo_write_alias_policy(char *data, const bool is_delete) { char *cp = strchr(data, ' '); if (!cp) return -EINVAL; *cp++ = '\0'; return tomoyo_update_alias_entry(data, cp, is_delete); } /* Domain create/delete handler. */ /** * tomoyo_delete_domain - Delete a domain. * * @domainname: The name of domain. * * Returns 0. */ int tomoyo_delete_domain(char *domainname) { struct tomoyo_domain_info *domain; struct tomoyo_path_info name; name.name = domainname; tomoyo_fill_path_info(&name); down_write(&tomoyo_domain_list_lock); /* Is there an active domain? */ list_for_each_entry(domain, &tomoyo_domain_list, list) { /* Never delete tomoyo_kernel_domain */ if (domain == &tomoyo_kernel_domain) continue; if (domain->is_deleted || tomoyo_pathcmp(domain->domainname, &name)) continue; domain->is_deleted = true; break; } up_write(&tomoyo_domain_list_lock); return 0; } /** * tomoyo_find_or_assign_new_domain - Create a domain. * * @domainname: The name of domain. * @profile: Profile number to assign if the domain was newly created. * * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise. */ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char * domainname, const u8 profile) { struct tomoyo_domain_info *domain = NULL; const struct tomoyo_path_info *saved_domainname; down_write(&tomoyo_domain_list_lock); domain = tomoyo_find_domain(domainname); if (domain) goto out; if (!tomoyo_is_correct_domain(domainname, __func__)) goto out; saved_domainname = tomoyo_save_name(domainname); if (!saved_domainname) goto out; /* Can I reuse memory of deleted domain? */ list_for_each_entry(domain, &tomoyo_domain_list, list) { struct task_struct *p; struct tomoyo_acl_info *ptr; bool flag; if (!domain->is_deleted || domain->domainname != saved_domainname) continue; flag = false; read_lock(&tasklist_lock); for_each_process(p) { if (tomoyo_real_domain(p) != domain) continue; flag = true; break; } read_unlock(&tasklist_lock); if (flag) continue; list_for_each_entry(ptr, &domain->acl_info_list, list) { ptr->type |= TOMOYO_ACL_DELETED; } tomoyo_set_domain_flag(domain, true, domain->flags); domain->profile = profile; domain->quota_warned = false; mb(); /* Avoid out-of-order execution. */ domain->is_deleted = false; goto out; } /* No memory reusable. Create using new memory. */ domain = tomoyo_alloc_element(sizeof(*domain)); if (domain) { INIT_LIST_HEAD(&domain->acl_info_list); domain->domainname = saved_domainname; domain->profile = profile; list_add_tail(&domain->list, &tomoyo_domain_list); } out: up_write(&tomoyo_domain_list_lock); return domain; } /** * tomoyo_find_next_domain - Find a domain. * * @bprm: Pointer to "struct linux_binprm". * @next_domain: Pointer to pointer to "struct tomoyo_domain_info". * * Returns 0 on success, negative value otherwise. */ int tomoyo_find_next_domain(struct linux_binprm *bprm, struct tomoyo_domain_info **next_domain) { /* * This function assumes that the size of buffer returned by * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN. */ struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp)); struct tomoyo_domain_info *old_domain = tomoyo_domain(); struct tomoyo_domain_info *domain = NULL; const char *old_domain_name = old_domain->domainname->name; const char *original_name = bprm->filename; char *new_domain_name = NULL; char *real_program_name = NULL; char *symlink_program_name = NULL; const u8 mode = tomoyo_check_flags(old_domain, TOMOYO_MAC_FOR_FILE); const bool is_enforce = (mode == 3); int retval = -ENOMEM; struct tomoyo_path_info r; /* real name */ struct tomoyo_path_info s; /* symlink name */ struct tomoyo_path_info l; /* last name */ static bool initialized; if (!tmp) goto out; if (!initialized) { /* * Built-in initializers. This is needed because policies are * not loaded until starting /sbin/init. */ tomoyo_update_domain_initializer_entry(NULL, "/sbin/hotplug", false, false); tomoyo_update_domain_initializer_entry(NULL, "/sbin/modprobe", false, false); initialized = true; } /* Get tomoyo_realpath of program. */ retval = -ENOENT; /* I hope tomoyo_realpath() won't fail with -ENOMEM. */ real_program_name = tomoyo_realpath(original_name); if (!real_program_name) goto out; /* Get tomoyo_realpath of symbolic link. */ symlink_program_name = tomoyo_realpath_nofollow(original_name); if (!symlink_program_name) goto out; r.name = real_program_name; tomoyo_fill_path_info(&r); s.name = symlink_program_name; tomoyo_fill_path_info(&s); l.name = tomoyo_get_last_name(old_domain); tomoyo_fill_path_info(&l); /* Check 'alias' directive. */ if (tomoyo_pathcmp(&r, &s)) { struct tomoyo_alias_entry *ptr; /* Is this program allowed to be called via symbolic links? */ down_read(&tomoyo_alias_list_lock); list_for_each_entry(ptr, &tomoyo_alias_list, list) { if (ptr->is_deleted || tomoyo_pathcmp(&r, ptr->original_name) || tomoyo_pathcmp(&s, ptr->aliased_name)) continue; memset(real_program_name, 0, TOMOYO_MAX_PATHNAME_LEN); strncpy(real_program_name, ptr->aliased_name->name, TOMOYO_MAX_PATHNAME_LEN - 1); tomoyo_fill_path_info(&r); break; } up_read(&tomoyo_alias_list_lock); } /* Check execute permission. */ retval = tomoyo_check_exec_perm(old_domain, &r, tmp); if (retval < 0) goto out; new_domain_name = tmp->buffer; if (tomoyo_is_domain_initializer(old_domain->domainname, &r, &l)) { /* Transit to the child of tomoyo_kernel_domain domain. */ snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, TOMOYO_ROOT_NAME " " "%s", real_program_name); } else if (old_domain == &tomoyo_kernel_domain && !tomoyo_policy_loaded) { /* * Needn't to transit from kernel domain before starting * /sbin/init. But transit from kernel domain if executing * initializers because they might start before /sbin/init. */ domain = old_domain; } else if (tomoyo_is_domain_keeper(old_domain->domainname, &r, &l)) { /* Keep current domain. */ domain = old_domain; } else { /* Normal domain transition. */ snprintf(new_domain_name, TOMOYO_MAX_PATHNAME_LEN + 1, "%s %s", old_domain_name, real_program_name); } if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN) goto done; down_read(&tomoyo_domain_list_lock); domain = tomoyo_find_domain(new_domain_name); up_read(&tomoyo_domain_list_lock); if (domain) goto done; if (is_enforce) goto done; domain = tomoyo_find_or_assign_new_domain(new_domain_name, old_domain->profile); done: if (domain) goto out; printk(KERN_WARNING "TOMOYO-ERROR: Domain '%s' not defined.\n", new_domain_name); if (is_enforce) retval = -EPERM; else tomoyo_set_domain_flag(old_domain, false, TOMOYO_DOMAIN_FLAGS_TRANSITION_FAILED); out: tomoyo_free(real_program_name); tomoyo_free(symlink_program_name); *next_domain = domain ? domain : old_domain; tomoyo_free(tmp); return retval; }