[people/ms/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 = 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.
 *
 * @inode: Pointer to "struct inode".
 * @file:  Pointer to "struct file".
 *
 * Returns 0 on success, negative value otherwise.
 */
static int tomoyo_release(struct inode *inode, struct file *file)
{
	return tomoyo_close_control(file->private_data);
}

/**
 * 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;
	46	data = kzalloc(count + 1, GFP_NOFS);
	47	if (!data)
	48	return -ENOMEM;
	49	if (copy_from_user(data, buf, count)) {
	50	error = -EFAULT;
	51	goto out;
	52	}
	53	tomoyo_normalize_line(data);
	54	if (tomoyo_correct_domain(data)) {
	55	const int idx = tomoyo_read_lock();
	56	struct tomoyo_path_info name;
	57	struct tomoyo_request_info r;
	58	name.name = data;
	59	tomoyo_fill_path_info(&name);
	60	/* Check "task manual_domain_transition" permission. */
	61	tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_EXECUTE);
	62	r.param_type = TOMOYO_TYPE_MANUAL_TASK_ACL;
	63	r.param.task.domainname = &name;
	64	tomoyo_check_acl(&r, tomoyo_check_task_acl);
	65	if (!r.granted)
	66	error = -EPERM;
	67	else {
	68	struct tomoyo_domain_info *new_domain =
	69	tomoyo_assign_domain(data, true);
	70	if (!new_domain) {
	71	error = -ENOENT;
	72	} else {
	73	struct cred *cred = prepare_creds();
74	if (!cred) {
75	error = -ENOMEM;
76	} else {
77	struct tomoyo_domain_info *old_domain =
78	cred->security;
79	cred->security = new_domain;
80	atomic_inc(&new_domain->users);
81	atomic_dec(&old_domain->users);
82	commit_creds(cred);
83	error = 0;
84	}
85	}
86	}
87	tomoyo_read_unlock(idx);
88	} else
89	error = -EINVAL;
90	out:
91	kfree(data);
92	return error ? error : count;
93	}
94
95	/**
96	* tomoyo_read_self - read() for /sys/kernel/security/tomoyo/self_domain interface.
97	*
98	* @file: Pointer to "struct file".
99	* @buf: Domainname which current thread belongs to.
100	* @count: Size of @buf.
101	* @ppos: Bytes read by now.
102	*
103	* Returns read size on success, negative value otherwise.
104	*/
105	static ssize_t tomoyo_read_self(struct file file, char __user buf,
106	size_t count, loff_t *ppos)
107	{
108	const char *domain = tomoyo_domain()->domainname->name;
109	loff_t len = strlen(domain);
110	loff_t pos = *ppos;
111	if (pos >= len \|\| !count)
112	return 0;
113	len -= pos;
114	if (count < len)
115	len = count;
116	if (copy_to_user(buf, domain + pos, len))
117	return -EFAULT;
118	*ppos += len;
119	return len;
120	}
121
122	/* Operations for /sys/kernel/security/tomoyo/self_domain interface. */
123	static const struct file_operations tomoyo_self_operations = {
124	.write = tomoyo_write_self,
125	.read = tomoyo_read_self,
126	};
127
c3ef1500 TH	128	/**
	129	* tomoyo_open - open() for /sys/kernel/security/tomoyo/ interface.
	130	*
	131	* @inode: Pointer to "struct inode".
	132	* @file: Pointer to "struct file".
	133	*
	134	* Returns 0 on success, negative value otherwise.
	135	*/
	136	static int tomoyo_open(struct inode inode, struct file file)
	137	{
496ad9aa	138	const int key = ((u8 *) file_inode(file)->i_private)
c3ef1500 TH	139	- ((u8 *) NULL);
	140	return tomoyo_open_control(key, file);
	141	}
	142
	143	/**
	144	* tomoyo_release - close() for /sys/kernel/security/tomoyo/ interface.
	145	*
	146	* @inode: Pointer to "struct inode".
	147	* @file: Pointer to "struct file".
	148	*
	149	* Returns 0 on success, negative value otherwise.
	150	*/
	151	static int tomoyo_release(struct inode inode, struct file file)
	152	{
0df7e8b8	153	return tomoyo_close_control(file->private_data);
c3ef1500 TH	154	}
c3ef1500 TH	155
0849e3ba	156	/**
b5bc60b4	157	* tomoyo_poll - poll() for /sys/kernel/security/tomoyo/ interface.
0849e3ba TH	158	*
0849e3ba TH	159	* @file: Pointer to "struct file".
6041e834	160	* @wait: Pointer to "poll_table". Maybe NULL.
0849e3ba	161	*
6041e834 TH	162	* Returns POLLIN \| POLLRDNORM \| POLLOUT \| POLLWRNORM if ready to read/write,
6041e834 TH	163	* POLLOUT \| POLLWRNORM otherwise.
0849e3ba TH	164	*/
	165	static unsigned int tomoyo_poll(struct file file, poll_table wait)
	166	{
	167	return tomoyo_poll_control(file, wait);
	168	}
	169
c3ef1500 TH	170	/**
	171	* tomoyo_read - read() for /sys/kernel/security/tomoyo/ interface.
	172	*
	173	* @file: Pointer to "struct file".
	174	* @buf: Pointer to buffer.
	175	* @count: Size of @buf.
	176	* @ppos: Unused.
	177	*
	178	* Returns bytes read on success, negative value otherwise.
	179	*/
	180	static ssize_t tomoyo_read(struct file file, char __user buf, size_t count,
	181	loff_t *ppos)
	182	{
0df7e8b8	183	return tomoyo_read_control(file->private_data, buf, count);
c3ef1500 TH	184	}
	185
	186	/**
	187	* tomoyo_write - write() for /sys/kernel/security/tomoyo/ interface.
	188	*
	189	* @file: Pointer to "struct file".
	190	* @buf: Pointer to buffer.
	191	* @count: Size of @buf.
	192	* @ppos: Unused.
	193	*
	194	* Returns @count on success, negative value otherwise.
	195	*/
	196	static ssize_t tomoyo_write(struct file file, const char __user buf,
	197	size_t count, loff_t *ppos)
	198	{
0df7e8b8	199	return tomoyo_write_control(file->private_data, buf, count);
c3ef1500 TH	200	}
	201
	202	/*
	203	* tomoyo_operations is a "struct file_operations" which is used for handling
	204	* /sys/kernel/security/tomoyo/ interface.
	205	*
	206	* Some files under /sys/kernel/security/tomoyo/ directory accept open(O_RDWR).
	207	* See tomoyo_io_buffer for internals.
	208	*/
	209	static const struct file_operations tomoyo_operations = {
	210	.open = tomoyo_open,
	211	.release = tomoyo_release,
0849e3ba	212	.poll = tomoyo_poll,
c3ef1500 TH	213	.read = tomoyo_read,
c3ef1500 TH	214	.write = tomoyo_write,
7e2deb7c	215	.llseek = noop_llseek,
c3ef1500 TH	216	};
	217
	218	/**
	219	* tomoyo_create_entry - Create interface files under /sys/kernel/security/tomoyo/ directory.
	220	*
	221	* @name: The name of the interface file.
	222	* @mode: The permission of the interface file.
	223	* @parent: The parent directory.
	224	* @key: Type of interface.
	225	*
	226	* Returns nothing.
	227	*/
52ef0c04	228	static void __init tomoyo_create_entry(const char *name, const umode_t mode,
c3ef1500 TH	229	struct dentry *parent, const u8 key)
	230	{
	231	securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key,
	232	&tomoyo_operations);
	233	}
	234
	235	/**
	236	* tomoyo_initerface_init - Initialize /sys/kernel/security/tomoyo/ interface.
	237	*
	238	* Returns 0.
	239	*/
	240	static int __init tomoyo_initerface_init(void)
	241	{
	242	struct dentry *tomoyo_dir;
	243
	244	/* Don't create securityfs entries unless registered. */
	245	if (current_cred()->security != &tomoyo_kernel_domain)
	246	return 0;
	247
	248	tomoyo_dir = securityfs_create_dir("tomoyo", NULL);
	249	tomoyo_create_entry("query", 0600, tomoyo_dir,
	250	TOMOYO_QUERY);
	251	tomoyo_create_entry("domain_policy", 0600, tomoyo_dir,
	252	TOMOYO_DOMAINPOLICY);
	253	tomoyo_create_entry("exception_policy", 0600, tomoyo_dir,
	254	TOMOYO_EXCEPTIONPOLICY);
eadd99cc TH	255	tomoyo_create_entry("audit", 0400, tomoyo_dir,
eadd99cc TH	256	TOMOYO_AUDIT);
c3ef1500 TH	257	tomoyo_create_entry(".process_status", 0600, tomoyo_dir,
c3ef1500 TH	258	TOMOYO_PROCESS_STATUS);
b22b8b9f TH	259	tomoyo_create_entry("stat", 0644, tomoyo_dir,
b22b8b9f TH	260	TOMOYO_STAT);
c3ef1500 TH	261	tomoyo_create_entry("profile", 0600, tomoyo_dir,
	262	TOMOYO_PROFILE);
	263	tomoyo_create_entry("manager", 0600, tomoyo_dir,
	264	TOMOYO_MANAGER);
	265	tomoyo_create_entry("version", 0400, tomoyo_dir,
	266	TOMOYO_VERSION);
731d37aa TH	267	securityfs_create_file("self_domain", 0666, tomoyo_dir, NULL,
731d37aa TH	268	&tomoyo_self_operations);
778c4a4d	269	tomoyo_load_builtin_policy();
c3ef1500 TH	270	return 0;
	271	}
	272
	273	fs_initcall(tomoyo_initerface_init);