diff options
Diffstat (limited to 'security/tomoyo/securityfs_if.c')
-rw-r--r-- | security/tomoyo/securityfs_if.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/security/tomoyo/securityfs_if.c b/security/tomoyo/securityfs_if.c new file mode 100644 index 000000000..1d3d7e7a1 --- /dev/null +++ b/security/tomoyo/securityfs_if.c @@ -0,0 +1,268 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * security/tomoyo/securityfs_if.c + * + * Copyright (C) 2005-2011 NTT DATA CORPORATION + */ + +#include <linux/security.h> +#include "common.h" + +/** + * tomoyo_check_task_acl - Check permission for task operation. + * + * @r: Pointer to "struct tomoyo_request_info". + * @ptr: Pointer to "struct tomoyo_acl_info". + * + * Returns true if granted, false otherwise. + */ +static bool tomoyo_check_task_acl(struct tomoyo_request_info *r, + const struct tomoyo_acl_info *ptr) +{ + const struct tomoyo_task_acl *acl = container_of(ptr, typeof(*acl), + head); + return !tomoyo_pathcmp(r->param.task.domainname, acl->domainname); +} + +/** + * tomoyo_write_self - write() for /sys/kernel/security/tomoyo/self_domain interface. + * + * @file: Pointer to "struct file". + * @buf: Domainname to transit to. + * @count: Size of @buf. + * @ppos: Unused. + * + * Returns @count on success, negative value otherwise. + * + * If domain transition was permitted but the domain transition failed, this + * function returns error rather than terminating current thread with SIGKILL. + */ +static ssize_t tomoyo_write_self(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + char *data; + int error; + if (!count || count >= TOMOYO_EXEC_TMPSIZE - 10) + return -ENOMEM; + data = memdup_user_nul(buf, count); + if (IS_ERR(data)) + return PTR_ERR(data); + tomoyo_normalize_line(data); + if (tomoyo_correct_domain(data)) { + const int idx = tomoyo_read_lock(); + struct tomoyo_path_info name; + struct tomoyo_request_info r; + name.name = data; + tomoyo_fill_path_info(&name); + /* Check "task manual_domain_transition" permission. */ + tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_EXECUTE); + r.param_type = TOMOYO_TYPE_MANUAL_TASK_ACL; + r.param.task.domainname = &name; + tomoyo_check_acl(&r, tomoyo_check_task_acl); + if (!r.granted) + error = -EPERM; + else { + struct tomoyo_domain_info *new_domain = + tomoyo_assign_domain(data, true); + if (!new_domain) { + error = -ENOENT; + } else { + struct cred *cred = prepare_creds(); + if (!cred) { + error = -ENOMEM; + } else { + struct tomoyo_domain_info *old_domain = + cred->security; + cred->security = new_domain; + atomic_inc(&new_domain->users); + atomic_dec(&old_domain->users); + commit_creds(cred); + error = 0; + } + } + } + tomoyo_read_unlock(idx); + } else + error = -EINVAL; + kfree(data); + return error ? error : count; +} + +/** + * tomoyo_read_self - read() for /sys/kernel/security/tomoyo/self_domain interface. + * + * @file: Pointer to "struct file". + * @buf: Domainname which current thread belongs to. + * @count: Size of @buf. + * @ppos: Bytes read by now. + * + * Returns read size on success, negative value otherwise. + */ +static ssize_t tomoyo_read_self(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + const char *domain = tomoyo_domain()->domainname->name; + loff_t len = strlen(domain); + loff_t pos = *ppos; + if (pos >= len || !count) + return 0; + len -= pos; + if (count < len) + len = count; + if (copy_to_user(buf, domain + pos, len)) + return -EFAULT; + *ppos += len; + return len; +} + +/* Operations for /sys/kernel/security/tomoyo/self_domain interface. */ +static const struct file_operations tomoyo_self_operations = { + .write = tomoyo_write_self, + .read = tomoyo_read_self, +}; + +/** + * tomoyo_open - open() for /sys/kernel/security/tomoyo/ interface. + * + * @inode: Pointer to "struct inode". + * @file: Pointer to "struct file". + * + * Returns 0 on success, negative value otherwise. + */ +static int tomoyo_open(struct inode *inode, struct file *file) +{ + const int key = ((u8 *) file_inode(file)->i_private) + - ((u8 *) NULL); + return tomoyo_open_control(key, file); +} + +/** + * tomoyo_release - close() for /sys/kernel/security/tomoyo/ interface. + * + * @file: Pointer to "struct file". + * + */ +static int tomoyo_release(struct inode *inode, struct file *file) +{ + tomoyo_close_control(file->private_data); + return 0; +} + +/** + * tomoyo_poll - poll() for /sys/kernel/security/tomoyo/ interface. + * + * @file: Pointer to "struct file". + * @wait: Pointer to "poll_table". Maybe NULL. + * + * Returns EPOLLIN | EPOLLRDNORM | EPOLLOUT | EPOLLWRNORM if ready to read/write, + * EPOLLOUT | EPOLLWRNORM otherwise. + */ +static __poll_t tomoyo_poll(struct file *file, poll_table *wait) +{ + return tomoyo_poll_control(file, wait); +} + +/** + * tomoyo_read - read() for /sys/kernel/security/tomoyo/ interface. + * + * @file: Pointer to "struct file". + * @buf: Pointer to buffer. + * @count: Size of @buf. + * @ppos: Unused. + * + * Returns bytes read on success, negative value otherwise. + */ +static ssize_t tomoyo_read(struct file *file, char __user *buf, size_t count, + loff_t *ppos) +{ + return tomoyo_read_control(file->private_data, buf, count); +} + +/** + * tomoyo_write - write() for /sys/kernel/security/tomoyo/ interface. + * + * @file: Pointer to "struct file". + * @buf: Pointer to buffer. + * @count: Size of @buf. + * @ppos: Unused. + * + * Returns @count on success, negative value otherwise. + */ +static ssize_t tomoyo_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return tomoyo_write_control(file->private_data, buf, count); +} + +/* + * tomoyo_operations is a "struct file_operations" which is used for handling + * /sys/kernel/security/tomoyo/ interface. + * + * Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR). + * See tomoyo_io_buffer for internals. + */ +static const struct file_operations tomoyo_operations = { + .open = tomoyo_open, + .release = tomoyo_release, + .poll = tomoyo_poll, + .read = tomoyo_read, + .write = tomoyo_write, + .llseek = noop_llseek, +}; + +/** + * tomoyo_create_entry - Create interface files under /sys/kernel/security/tomoyo/ directory. + * + * @name: The name of the interface file. + * @mode: The permission of the interface file. + * @parent: The parent directory. + * @key: Type of interface. + * + * Returns nothing. + */ +static void __init tomoyo_create_entry(const char *name, const umode_t mode, + struct dentry *parent, const u8 key) +{ + securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key, + &tomoyo_operations); +} + +/** + * tomoyo_initerface_init - Initialize /sys/kernel/security/tomoyo/ interface. + * + * Returns 0. + */ +static int __init tomoyo_initerface_init(void) +{ + struct dentry *tomoyo_dir; + + /* Don't create securityfs entries unless registered. */ + if (current_cred()->security != &tomoyo_kernel_domain) + return 0; + + tomoyo_dir = securityfs_create_dir("tomoyo", NULL); + tomoyo_create_entry("query", 0600, tomoyo_dir, + TOMOYO_QUERY); + tomoyo_create_entry("domain_policy", 0600, tomoyo_dir, + TOMOYO_DOMAINPOLICY); + tomoyo_create_entry("exception_policy", 0600, tomoyo_dir, + TOMOYO_EXCEPTIONPOLICY); + tomoyo_create_entry("audit", 0400, tomoyo_dir, + TOMOYO_AUDIT); + tomoyo_create_entry(".process_status", 0600, tomoyo_dir, + TOMOYO_PROCESS_STATUS); + tomoyo_create_entry("stat", 0644, tomoyo_dir, + TOMOYO_STAT); + tomoyo_create_entry("profile", 0600, tomoyo_dir, + TOMOYO_PROFILE); + tomoyo_create_entry("manager", 0600, tomoyo_dir, + TOMOYO_MANAGER); + tomoyo_create_entry("version", 0400, tomoyo_dir, + TOMOYO_VERSION); + securityfs_create_file("self_domain", 0666, tomoyo_dir, NULL, + &tomoyo_self_operations); + tomoyo_load_builtin_policy(); + return 0; +} + +fs_initcall(tomoyo_initerface_init); |