[deliverable/linux.git] / security / tomoyo / securityfs_if.c

/*
 * 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 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);
Commit	Line	Data
c3ef1500	1	/*
0f2a55d5	2	* security/tomoyo/securityfs_if.c
c3ef1500	3	*
0f2a55d5	4	* Copyright (C) 2005-2011 NTT DATA CORPORATION
c3ef1500 TH	5	*/
	6
	7	#include <linux/security.h>
	8	#include "common.h"
	9
731d37aa TH	10	/**
	11	* tomoyo_check_task_acl - Check permission for task operation.
	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_task_acl(struct tomoyo_request_info *r,
	19	const struct tomoyo_acl_info *ptr)
	20	{
	21	const struct tomoyo_task_acl acl = container_of(ptr, typeof(acl),
	22	head);
	23	return !tomoyo_pathcmp(r->param.task.domainname, acl->domainname);
	24	}
	25
	26	/**
	27	* tomoyo_write_self - write() for /sys/kernel/security/tomoyo/self_domain interface.
	28	*
	29	* @file: Pointer to "struct file".
	30	* @buf: Domainname to transit to.
	31	* @count: Size of @buf.
	32	* @ppos: Unused.
	33	*
	34	* Returns @count on success, negative value otherwise.
	35	*
	36	* If domain transition was permitted but the domain transition failed, this
	37	* function returns error rather than terminating current thread with SIGKILL.
	38	*/
	39	static ssize_t tomoyo_write_self(struct file file, const char __user buf,
	40	size_t count, loff_t *ppos)
	41	{
	42	char *data;
	43	int error;
	44	if (!count \|\| count >= TOMOYO_EXEC_TMPSIZE - 10)
	45	return -ENOMEM;
16e5c1fc AV	46	data = memdup_user_nul(buf, count);
	47	if (IS_ERR(data))
	48	return PTR_ERR(data);
731d37aa TH	49	tomoyo_normalize_line(data);
	50	if (tomoyo_correct_domain(data)) {
	51	const int idx = tomoyo_read_lock();
	52	struct tomoyo_path_info name;
	53	struct tomoyo_request_info r;
	54	name.name = data;
	55	tomoyo_fill_path_info(&name);
	56	/* Check "task manual_domain_transition" permission. */
	57	tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_EXECUTE);
	58	r.param_type = TOMOYO_TYPE_MANUAL_TASK_ACL;
	59	r.param.task.domainname = &name;
	60	tomoyo_check_acl(&r, tomoyo_check_task_acl);
	61	if (!r.granted)
	62	error = -EPERM;
	63	else {
	64	struct tomoyo_domain_info *new_domain =
	65	tomoyo_assign_domain(data, true);
	66	if (!new_domain) {
	67	error = -ENOENT;
	68	} else {
	69	struct cred *cred = prepare_creds();
	70	if (!cred) {
	71	error = -ENOMEM;
	72	} else {
	73	struct tomoyo_domain_info *old_domain =
	74	cred->security;
	75	cred->security = new_domain;
	76	atomic_inc(&new_domain->users);
	77	atomic_dec(&old_domain->users);
	78	commit_creds(cred);
	79	error = 0;
	80	}
	81	}
	82	}
	83	tomoyo_read_unlock(idx);
	84	} else
	85	error = -EINVAL;
731d37aa TH	86	kfree(data);
	87	return error ? error : count;
	88	}
	89
	90	/**
	91	* tomoyo_read_self - read() for /sys/kernel/security/tomoyo/self_domain interface.
	92	*
	93	* @file: Pointer to "struct file".
	94	* @buf: Domainname which current thread belongs to.
	95	* @count: Size of @buf.
	96	* @ppos: Bytes read by now.
	97	*
	98	* Returns read size on success, negative value otherwise.
	99	*/
	100	static ssize_t tomoyo_read_self(struct file file, char __user buf,
	101	size_t count, loff_t *ppos)
	102	{
	103	const char *domain = tomoyo_domain()->domainname->name;
	104	loff_t len = strlen(domain);
	105	loff_t pos = *ppos;
	106	if (pos >= len \|\| !count)
	107	return 0;
	108	len -= pos;
	109	if (count < len)
	110	len = count;
	111	if (copy_to_user(buf, domain + pos, len))
	112	return -EFAULT;
	113	*ppos += len;
	114	return len;
	115	}
	116
	117	/* Operations for /sys/kernel/security/tomoyo/self_domain interface. */
	118	static const struct file_operations tomoyo_self_operations = {
	119	.write = tomoyo_write_self,
	120	.read = tomoyo_read_self,
	121	};
	122
c3ef1500 TH	123	/**
	124	* tomoyo_open - open() for /sys/kernel/security/tomoyo/ interface.
	125	*
	126	* @inode: Pointer to "struct inode".
	127	* @file: Pointer to "struct file".
	128	*
	129	* Returns 0 on success, negative value otherwise.
	130	*/
	131	static int tomoyo_open(struct inode inode, struct file file)
	132	{
496ad9aa	133	const int key = ((u8 *) file_inode(file)->i_private)
c3ef1500 TH	134	- ((u8 *) NULL);
	135	return tomoyo_open_control(key, file);
	136	}
	137
	138	/**
	139	* tomoyo_release - close() for /sys/kernel/security/tomoyo/ interface.
	140	*
c3ef1500 TH	141	* @file: Pointer to "struct file".
c3ef1500 TH	142	*
c3ef1500 TH	143	*/
	144	static int tomoyo_release(struct inode inode, struct file file)
	145	{
e53cfda5 AV	146	tomoyo_close_control(file->private_data);
e53cfda5 AV	147	return 0;
c3ef1500 TH	148	}
c3ef1500 TH	149
0849e3ba	150	/**
b5bc60b4	151	* tomoyo_poll - poll() for /sys/kernel/security/tomoyo/ interface.
0849e3ba TH	152	*
0849e3ba TH	153	* @file: Pointer to "struct file".
6041e834	154	* @wait: Pointer to "poll_table". Maybe NULL.
0849e3ba	155	*
6041e834 TH	156	* Returns POLLIN \| POLLRDNORM \| POLLOUT \| POLLWRNORM if ready to read/write,
6041e834 TH	157	* POLLOUT \| POLLWRNORM otherwise.
0849e3ba TH	158	*/
	159	static unsigned int tomoyo_poll(struct file file, poll_table wait)
	160	{
	161	return tomoyo_poll_control(file, wait);
	162	}
	163
c3ef1500 TH	164	/**
	165	* tomoyo_read - read() for /sys/kernel/security/tomoyo/ interface.
	166	*
	167	* @file: Pointer to "struct file".
	168	* @buf: Pointer to buffer.
	169	* @count: Size of @buf.
	170	* @ppos: Unused.
	171	*
	172	* Returns bytes read on success, negative value otherwise.
	173	*/
	174	static ssize_t tomoyo_read(struct file file, char __user buf, size_t count,
	175	loff_t *ppos)
	176	{
0df7e8b8	177	return tomoyo_read_control(file->private_data, buf, count);
c3ef1500 TH	178	}
	179
	180	/**
	181	* tomoyo_write - write() for /sys/kernel/security/tomoyo/ interface.
	182	*
	183	* @file: Pointer to "struct file".
	184	* @buf: Pointer to buffer.
	185	* @count: Size of @buf.
	186	* @ppos: Unused.
	187	*
	188	* Returns @count on success, negative value otherwise.
	189	*/
	190	static ssize_t tomoyo_write(struct file file, const char __user buf,
	191	size_t count, loff_t *ppos)
	192	{
0df7e8b8	193	return tomoyo_write_control(file->private_data, buf, count);
c3ef1500 TH	194	}
	195
	196	/*
	197	* tomoyo_operations is a "struct file_operations" which is used for handling
	198	* /sys/kernel/security/tomoyo/ interface.
	199	*
	200	* Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR).
	201	* See tomoyo_io_buffer for internals.
	202	*/
	203	static const struct file_operations tomoyo_operations = {
	204	.open = tomoyo_open,
	205	.release = tomoyo_release,
0849e3ba	206	.poll = tomoyo_poll,
c3ef1500 TH	207	.read = tomoyo_read,
c3ef1500 TH	208	.write = tomoyo_write,
7e2deb7c	209	.llseek = noop_llseek,
c3ef1500 TH	210	};
	211
	212	/**
	213	* tomoyo_create_entry - Create interface files under /sys/kernel/security/tomoyo/ directory.
	214	*
	215	* @name: The name of the interface file.
	216	* @mode: The permission of the interface file.
	217	* @parent: The parent directory.
	218	* @key: Type of interface.
	219	*
	220	* Returns nothing.
	221	*/
52ef0c04	222	static void __init tomoyo_create_entry(const char *name, const umode_t mode,
c3ef1500 TH	223	struct dentry *parent, const u8 key)
	224	{
	225	securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key,
	226	&tomoyo_operations);
	227	}
	228
	229	/**
	230	* tomoyo_initerface_init - Initialize /sys/kernel/security/tomoyo/ interface.
	231	*
	232	* Returns 0.
	233	*/
	234	static int __init tomoyo_initerface_init(void)
	235	{
	236	struct dentry *tomoyo_dir;
	237
	238	/* Don't create securityfs entries unless registered. */
	239	if (current_cred()->security != &tomoyo_kernel_domain)
	240	return 0;
	241
	242	tomoyo_dir = securityfs_create_dir("tomoyo", NULL);
	243	tomoyo_create_entry("query", 0600, tomoyo_dir,
	244	TOMOYO_QUERY);
	245	tomoyo_create_entry("domain_policy", 0600, tomoyo_dir,
	246	TOMOYO_DOMAINPOLICY);
	247	tomoyo_create_entry("exception_policy", 0600, tomoyo_dir,
	248	TOMOYO_EXCEPTIONPOLICY);
eadd99cc TH	249	tomoyo_create_entry("audit", 0400, tomoyo_dir,
eadd99cc TH	250	TOMOYO_AUDIT);
c3ef1500 TH	251	tomoyo_create_entry(".process_status", 0600, tomoyo_dir,
c3ef1500 TH	252	TOMOYO_PROCESS_STATUS);
b22b8b9f TH	253	tomoyo_create_entry("stat", 0644, tomoyo_dir,
b22b8b9f TH	254	TOMOYO_STAT);
c3ef1500 TH	255	tomoyo_create_entry("profile", 0600, tomoyo_dir,
	256	TOMOYO_PROFILE);
	257	tomoyo_create_entry("manager", 0600, tomoyo_dir,
	258	TOMOYO_MANAGER);
	259	tomoyo_create_entry("version", 0400, tomoyo_dir,
	260	TOMOYO_VERSION);
731d37aa TH	261	securityfs_create_file("self_domain", 0666, tomoyo_dir, NULL,
731d37aa TH	262	&tomoyo_self_operations);
778c4a4d	263	tomoyo_load_builtin_policy();
c3ef1500 TH	264	return 0;
	265	}
	266
	267	fs_initcall(tomoyo_initerface_init);