/*
* 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 = kzalloc(count + 1, GFP_NOFS);
if (!data)
return -ENOMEM;
if (copy_from_user(data, buf, count)) {
error = -EFAULT;
goto out;
}
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;
out:
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 POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM if ready to read/write,
* POLLOUT | POLLWRNORM otherwise.
*/
static unsigned int 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);
