selinuxfs.c 38.3 KB
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/* Updated: Karl MacMillan <kmacmillan@tresys.com>
 *
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 *	Added conditional policy language extensions
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 *
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 *  Updated: Hewlett-Packard <paul.moore@hp.com>
 *
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 *	Added support for the policy capability bitmap
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 *
 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
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 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *	This program is free software; you can redistribute it and/or modify
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 *	it under the terms of the GNU General Public License as published by
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 *	the Free Software Foundation, version 2.
 */

#include <linux/kernel.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
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#include <linux/mutex.h>
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#include <linux/init.h>
#include <linux/string.h>
#include <linux/security.h>
#include <linux/major.h>
#include <linux/seq_file.h>
#include <linux/percpu.h>
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#include <linux/audit.h>
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#include <linux/uaccess.h>
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/* selinuxfs pseudo filesystem for exporting the security policy API.
   Based on the proc code and the fs/nfsd/nfsctl.c code. */

#include "flask.h"
#include "avc.h"
#include "avc_ss.h"
#include "security.h"
#include "objsec.h"
#include "conditional.h"

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/* Policy capability filenames */
static char *policycap_names[] = {
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	"network_peer_controls",
	"open_perms"
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};

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unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;

static int __init checkreqprot_setup(char *str)
{
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	unsigned long checkreqprot;
	if (!strict_strtoul(str, 0, &checkreqprot))
		selinux_checkreqprot = checkreqprot ? 1 : 0;
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	return 1;
}
__setup("checkreqprot=", checkreqprot_setup);

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static DEFINE_MUTEX(sel_mutex);
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/* global data for booleans */
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static struct dentry *bool_dir;
static int bool_num;
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static char **bool_pending_names;
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static int *bool_pending_values;
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/* global data for classes */
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static struct dentry *class_dir;
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static unsigned long last_class_ino;

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/* global data for policy capabilities */
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static struct dentry *policycap_dir;
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extern void selnl_notify_setenforce(int val);

/* Check whether a task is allowed to use a security operation. */
static int task_has_security(struct task_struct *tsk,
			     u32 perms)
{
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	const struct task_security_struct *tsec;
	u32 sid = 0;

	rcu_read_lock();
	tsec = __task_cred(tsk)->security;
	if (tsec)
		sid = tsec->sid;
	rcu_read_unlock();
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	if (!tsec)
		return -EACCES;

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	return avc_has_perm(sid, SECINITSID_SECURITY,
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			    SECCLASS_SECURITY, perms, NULL);
}

enum sel_inos {
	SEL_ROOT_INO = 2,
	SEL_LOAD,	/* load policy */
	SEL_ENFORCE,	/* get or set enforcing status */
	SEL_CONTEXT,	/* validate context */
	SEL_ACCESS,	/* compute access decision */
	SEL_CREATE,	/* compute create labeling decision */
	SEL_RELABEL,	/* compute relabeling decision */
	SEL_USER,	/* compute reachable user contexts */
	SEL_POLICYVERS,	/* return policy version for this kernel */
	SEL_COMMIT_BOOLS, /* commit new boolean values */
	SEL_MLS,	/* return if MLS policy is enabled */
	SEL_DISABLE,	/* disable SELinux until next reboot */
	SEL_MEMBER,	/* compute polyinstantiation membership decision */
	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
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	SEL_COMPAT_NET,	/* whether to use old compat network packet controls */
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	SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
	SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
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	SEL_INO_NEXT,	/* The next inode number to use */
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};

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static unsigned long sel_last_ino = SEL_INO_NEXT - 1;

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#define SEL_INITCON_INO_OFFSET		0x01000000
#define SEL_BOOL_INO_OFFSET		0x02000000
#define SEL_CLASS_INO_OFFSET		0x04000000
#define SEL_POLICYCAP_INO_OFFSET	0x08000000
#define SEL_INO_MASK			0x00ffffff
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#define TMPBUFLEN	12
static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
				size_t count, loff_t *ppos)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;

	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
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				 size_t count, loff_t *ppos)

{
	char *page;
	ssize_t length;
	int new_value;

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	if (count >= PAGE_SIZE)
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		return -ENOMEM;
	if (*ppos != 0) {
		/* No partial writes. */
		return -EINVAL;
	}
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	page = (char *)get_zeroed_page(GFP_KERNEL);
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	if (!page)
		return -ENOMEM;
	length = -EFAULT;
	if (copy_from_user(page, buf, count))
		goto out;

	length = -EINVAL;
	if (sscanf(page, "%d", &new_value) != 1)
		goto out;

	if (new_value != selinux_enforcing) {
		length = task_has_security(current, SECURITY__SETENFORCE);
		if (length)
			goto out;
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		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
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			"enforcing=%d old_enforcing=%d auid=%u ses=%u",
			new_value, selinux_enforcing,
			audit_get_loginuid(current),
			audit_get_sessionid(current));
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		selinux_enforcing = new_value;
		if (selinux_enforcing)
			avc_ss_reset(0);
		selnl_notify_setenforce(selinux_enforcing);
	}
	length = count;
out:
	free_page((unsigned long) page);
	return length;
}
#else
#define sel_write_enforce NULL
#endif

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static const struct file_operations sel_enforce_ops = {
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	.read		= sel_read_enforce,
	.write		= sel_write_enforce,
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	.llseek		= generic_file_llseek,
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};

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static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
					size_t count, loff_t *ppos)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;
	ino_t ino = filp->f_path.dentry->d_inode->i_ino;
	int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
		security_get_reject_unknown() : !security_get_allow_unknown();

	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

static const struct file_operations sel_handle_unknown_ops = {
	.read		= sel_read_handle_unknown,
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	.llseek		= generic_file_llseek,
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};

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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
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static ssize_t sel_write_disable(struct file *file, const char __user *buf,
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				 size_t count, loff_t *ppos)

{
	char *page;
	ssize_t length;
	int new_value;
	extern int selinux_disable(void);

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	if (count >= PAGE_SIZE)
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		return -ENOMEM;
	if (*ppos != 0) {
		/* No partial writes. */
		return -EINVAL;
	}
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	page = (char *)get_zeroed_page(GFP_KERNEL);
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	if (!page)
		return -ENOMEM;
	length = -EFAULT;
	if (copy_from_user(page, buf, count))
		goto out;

	length = -EINVAL;
	if (sscanf(page, "%d", &new_value) != 1)
		goto out;

	if (new_value) {
		length = selinux_disable();
		if (length < 0)
			goto out;
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		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
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			"selinux=0 auid=%u ses=%u",
			audit_get_loginuid(current),
			audit_get_sessionid(current));
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	}

	length = count;
out:
	free_page((unsigned long) page);
	return length;
}
#else
#define sel_write_disable NULL
#endif

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static const struct file_operations sel_disable_ops = {
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	.write		= sel_write_disable,
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	.llseek		= generic_file_llseek,
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};

static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
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				   size_t count, loff_t *ppos)
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{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;

	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

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static const struct file_operations sel_policyvers_ops = {
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	.read		= sel_read_policyvers,
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	.llseek		= generic_file_llseek,
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};

/* declaration for sel_write_load */
static int sel_make_bools(void);
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static int sel_make_classes(void);
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static int sel_make_policycap(void);
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/* declaration for sel_make_class_dirs */
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
			unsigned long *ino);
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static ssize_t sel_read_mls(struct file *filp, char __user *buf,
				size_t count, loff_t *ppos)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;

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	length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
			   security_mls_enabled());
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	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

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static const struct file_operations sel_mls_ops = {
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	.read		= sel_read_mls,
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	.llseek		= generic_file_llseek,
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};

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static ssize_t sel_write_load(struct file *file, const char __user *buf,
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			      size_t count, loff_t *ppos)

{
	int ret;
	ssize_t length;
	void *data = NULL;

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	mutex_lock(&sel_mutex);
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	length = task_has_security(current, SECURITY__LOAD_POLICY);
	if (length)
		goto out;

	if (*ppos != 0) {
		/* No partial writes. */
		length = -EINVAL;
		goto out;
	}

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	if ((count > 64 * 1024 * 1024)
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	    || (data = vmalloc(count)) == NULL) {
		length = -ENOMEM;
		goto out;
	}

	length = -EFAULT;
	if (copy_from_user(data, buf, count) != 0)
		goto out;

	length = security_load_policy(data, count);
	if (length)
		goto out;

	ret = sel_make_bools();
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	if (ret) {
		length = ret;
		goto out1;
	}

	ret = sel_make_classes();
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	if (ret) {
		length = ret;
		goto out1;
	}

	ret = sel_make_policycap();
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	if (ret)
		length = ret;
	else
		length = count;
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out1:
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	audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
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		"policy loaded auid=%u ses=%u",
		audit_get_loginuid(current),
		audit_get_sessionid(current));
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out:
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	mutex_unlock(&sel_mutex);
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	vfree(data);
	return length;
}

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static const struct file_operations sel_load_ops = {
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	.write		= sel_write_load,
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	.llseek		= generic_file_llseek,
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};

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static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
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{
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	char *canon;
	u32 sid, len;
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	ssize_t length;

	length = task_has_security(current, SECURITY__CHECK_CONTEXT);
	if (length)
		return length;

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	length = security_context_to_sid(buf, size, &sid);
	if (length < 0)
		return length;
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	length = security_sid_to_context(sid, &canon, &len);
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	if (length < 0)
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		return length;

	if (len > SIMPLE_TRANSACTION_LIMIT) {
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		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
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		length = -ERANGE;
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		goto out;
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	}
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	memcpy(buf, canon, len);
	length = len;
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out:
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	kfree(canon);
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	return length;
}

static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
				     size_t count, loff_t *ppos)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;

	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

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static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
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				      size_t count, loff_t *ppos)
{
	char *page;
	ssize_t length;
	unsigned int new_value;

	length = task_has_security(current, SECURITY__SETCHECKREQPROT);
	if (length)
		return length;

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	if (count >= PAGE_SIZE)
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		return -ENOMEM;
	if (*ppos != 0) {
		/* No partial writes. */
		return -EINVAL;
	}
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	page = (char *)get_zeroed_page(GFP_KERNEL);
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	if (!page)
		return -ENOMEM;
	length = -EFAULT;
	if (copy_from_user(page, buf, count))
		goto out;

	length = -EINVAL;
	if (sscanf(page, "%u", &new_value) != 1)
		goto out;

	selinux_checkreqprot = new_value ? 1 : 0;
	length = count;
out:
	free_page((unsigned long) page);
	return length;
}
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static const struct file_operations sel_checkreqprot_ops = {
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	.read		= sel_read_checkreqprot,
	.write		= sel_write_checkreqprot,
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	.llseek		= generic_file_llseek,
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};

/*
 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 */
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static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
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static ssize_t (*write_op[])(struct file *, char *, size_t) = {
	[SEL_ACCESS] = sel_write_access,
	[SEL_CREATE] = sel_write_create,
	[SEL_RELABEL] = sel_write_relabel,
	[SEL_USER] = sel_write_user,
	[SEL_MEMBER] = sel_write_member,
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	[SEL_CONTEXT] = sel_write_context,
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};

static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
{
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	ino_t ino = file->f_path.dentry->d_inode->i_ino;
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	char *data;
	ssize_t rv;

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	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
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		return -EINVAL;

	data = simple_transaction_get(file, buf, size);
	if (IS_ERR(data))
		return PTR_ERR(data);

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	rv = write_op[ino](file, data, size);
	if (rv > 0) {
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		simple_transaction_set(file, rv);
		rv = size;
	}
	return rv;
}

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static const struct file_operations transaction_ops = {
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	.write		= selinux_transaction_write,
	.read		= simple_transaction_read,
	.release	= simple_transaction_release,
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	.llseek		= generic_file_llseek,
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};

/*
 * payload - write methods
 * If the method has a response, the response should be put in buf,
 * and the length returned.  Otherwise return 0 or and -error.
 */

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static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
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{
	char *scon, *tcon;
	u32 ssid, tsid;
	u16 tclass;
	struct av_decision avd;
	ssize_t length;

	length = task_has_security(current, SECURITY__COMPUTE_AV);
	if (length)
		return length;

	length = -ENOMEM;
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	scon = kzalloc(size + 1, GFP_KERNEL);
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	if (!scon)
		return length;

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	tcon = kzalloc(size + 1, GFP_KERNEL);
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	if (!tcon)
		goto out;

	length = -EINVAL;
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	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
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		goto out2;

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	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
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	if (length < 0)
		goto out2;
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	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
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	if (length < 0)
		goto out2;

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	security_compute_av_user(ssid, tsid, tclass, &avd);
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	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
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			  "%x %x %x %x %u %x",
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			  avd.allowed, 0xffffffff,
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			  avd.auditallow, avd.auditdeny,
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			  avd.seqno, avd.flags);
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out2:
	kfree(tcon);
out:
	kfree(scon);
	return length;
}

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static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
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{
	char *scon, *tcon;
	u32 ssid, tsid, newsid;
	u16 tclass;
	ssize_t length;
	char *newcon;
	u32 len;

	length = task_has_security(current, SECURITY__COMPUTE_CREATE);
	if (length)
		return length;

	length = -ENOMEM;
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	scon = kzalloc(size + 1, GFP_KERNEL);
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	if (!scon)
		return length;

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	tcon = kzalloc(size + 1, GFP_KERNEL);
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	if (!tcon)
		goto out;

	length = -EINVAL;
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
		goto out2;

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	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
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	if (length < 0)
		goto out2;
576
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
577 578 579
	if (length < 0)
		goto out2;

580
	length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
L
Linus Torvalds 已提交
581 582 583 584 585 586 587 588
	if (length < 0)
		goto out2;

	length = security_sid_to_context(newsid, &newcon, &len);
	if (length < 0)
		goto out2;

	if (len > SIMPLE_TRANSACTION_LIMIT) {
E
Eric Paris 已提交
589 590
		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
L
Linus Torvalds 已提交
591 592 593 594 595 596 597 598 599 600 601 602 603 604 605
		length = -ERANGE;
		goto out3;
	}

	memcpy(buf, newcon, len);
	length = len;
out3:
	kfree(newcon);
out2:
	kfree(tcon);
out:
	kfree(scon);
	return length;
}

606
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
607 608 609 610 611 612 613 614 615 616 617 618 619
{
	char *scon, *tcon;
	u32 ssid, tsid, newsid;
	u16 tclass;
	ssize_t length;
	char *newcon;
	u32 len;

	length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
	if (length)
		return length;

	length = -ENOMEM;
620
	scon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
621 622 623
	if (!scon)
		return length;

624
	tcon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
625 626 627 628 629 630 631
	if (!tcon)
		goto out;

	length = -EINVAL;
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
		goto out2;

632
	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
L
Linus Torvalds 已提交
633 634
	if (length < 0)
		goto out2;
635
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662
	if (length < 0)
		goto out2;

	length = security_change_sid(ssid, tsid, tclass, &newsid);
	if (length < 0)
		goto out2;

	length = security_sid_to_context(newsid, &newcon, &len);
	if (length < 0)
		goto out2;

	if (len > SIMPLE_TRANSACTION_LIMIT) {
		length = -ERANGE;
		goto out3;
	}

	memcpy(buf, newcon, len);
	length = len;
out3:
	kfree(newcon);
out2:
	kfree(tcon);
out:
	kfree(scon);
	return length;
}

663
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
664 665 666 667 668 669 670 671 672 673 674 675 676
{
	char *con, *user, *ptr;
	u32 sid, *sids;
	ssize_t length;
	char *newcon;
	int i, rc;
	u32 len, nsids;

	length = task_has_security(current, SECURITY__COMPUTE_USER);
	if (length)
		return length;

	length = -ENOMEM;
677
	con = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
678 679 680
	if (!con)
		return length;

681
	user = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
682 683 684 685 686 687 688
	if (!user)
		goto out;

	length = -EINVAL;
	if (sscanf(buf, "%s %s", con, user) != 2)
		goto out2;

689
	length = security_context_to_sid(con, strlen(con) + 1, &sid);
L
Linus Torvalds 已提交
690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723
	if (length < 0)
		goto out2;

	length = security_get_user_sids(sid, user, &sids, &nsids);
	if (length < 0)
		goto out2;

	length = sprintf(buf, "%u", nsids) + 1;
	ptr = buf + length;
	for (i = 0; i < nsids; i++) {
		rc = security_sid_to_context(sids[i], &newcon, &len);
		if (rc) {
			length = rc;
			goto out3;
		}
		if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
			kfree(newcon);
			length = -ERANGE;
			goto out3;
		}
		memcpy(ptr, newcon, len);
		kfree(newcon);
		ptr += len;
		length += len;
	}
out3:
	kfree(sids);
out2:
	kfree(user);
out:
	kfree(con);
	return length;
}

724
static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
725 726 727 728 729 730 731 732 733 734 735 736 737
{
	char *scon, *tcon;
	u32 ssid, tsid, newsid;
	u16 tclass;
	ssize_t length;
	char *newcon;
	u32 len;

	length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
	if (length)
		return length;

	length = -ENOMEM;
738
	scon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
739 740 741
	if (!scon)
		return length;

742
	tcon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
743 744 745 746 747 748 749
	if (!tcon)
		goto out;

	length = -EINVAL;
	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
		goto out2;

750
	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
L
Linus Torvalds 已提交
751 752
	if (length < 0)
		goto out2;
753
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
754 755 756 757 758 759 760 761 762 763 764 765
	if (length < 0)
		goto out2;

	length = security_member_sid(ssid, tsid, tclass, &newsid);
	if (length < 0)
		goto out2;

	length = security_sid_to_context(newsid, &newcon, &len);
	if (length < 0)
		goto out2;

	if (len > SIMPLE_TRANSACTION_LIMIT) {
E
Eric Paris 已提交
766 767
		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
L
Linus Torvalds 已提交
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
		length = -ERANGE;
		goto out3;
	}

	memcpy(buf, newcon, len);
	length = len;
out3:
	kfree(newcon);
out2:
	kfree(tcon);
out:
	kfree(scon);
	return length;
}

static struct inode *sel_make_inode(struct super_block *sb, int mode)
{
	struct inode *ret = new_inode(sb);

	if (ret) {
		ret->i_mode = mode;
		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
	}
	return ret;
}

static ssize_t sel_read_bool(struct file *filep, char __user *buf,
			     size_t count, loff_t *ppos)
{
	char *page = NULL;
	ssize_t length;
	ssize_t ret;
	int cur_enforcing;
S
Stephen Smalley 已提交
801 802 803
	struct inode *inode = filep->f_path.dentry->d_inode;
	unsigned index = inode->i_ino & SEL_INO_MASK;
	const char *name = filep->f_path.dentry->d_name.name;
L
Linus Torvalds 已提交
804

I
Ingo Molnar 已提交
805
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
806

S
Stephen Smalley 已提交
807 808 809 810
	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
		ret = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
811

812 813
	page = (char *)get_zeroed_page(GFP_KERNEL);
	if (!page) {
L
Linus Torvalds 已提交
814 815 816 817
		ret = -ENOMEM;
		goto out;
	}

S
Stephen Smalley 已提交
818
	cur_enforcing = security_get_bool_value(index);
L
Linus Torvalds 已提交
819 820 821 822 823
	if (cur_enforcing < 0) {
		ret = cur_enforcing;
		goto out;
	}
	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
S
Stephen Smalley 已提交
824
			  bool_pending_values[index]);
825
	ret = simple_read_from_buffer(buf, count, ppos, page, length);
L
Linus Torvalds 已提交
826
out:
I
Ingo Molnar 已提交
827
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
828 829 830 831 832 833 834 835 836
	if (page)
		free_page((unsigned long)page);
	return ret;
}

static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
			      size_t count, loff_t *ppos)
{
	char *page = NULL;
S
Stephen Smalley 已提交
837
	ssize_t length;
L
Linus Torvalds 已提交
838
	int new_value;
S
Stephen Smalley 已提交
839 840 841
	struct inode *inode = filep->f_path.dentry->d_inode;
	unsigned index = inode->i_ino & SEL_INO_MASK;
	const char *name = filep->f_path.dentry->d_name.name;
L
Linus Torvalds 已提交
842

I
Ingo Molnar 已提交
843
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
844 845 846 847 848

	length = task_has_security(current, SECURITY__SETBOOL);
	if (length)
		goto out;

S
Stephen Smalley 已提交
849 850 851 852 853
	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
		length = -EINVAL;
		goto out;
	}

854
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
855 856 857
		length = -ENOMEM;
		goto out;
	}
S
Stephen Smalley 已提交
858

L
Linus Torvalds 已提交
859 860
	if (*ppos != 0) {
		/* No partial writes. */
S
Stephen Smalley 已提交
861
		length = -EINVAL;
L
Linus Torvalds 已提交
862 863
		goto out;
	}
864
	page = (char *)get_zeroed_page(GFP_KERNEL);
L
Linus Torvalds 已提交
865 866 867 868 869
	if (!page) {
		length = -ENOMEM;
		goto out;
	}

S
Stephen Smalley 已提交
870
	length = -EFAULT;
L
Linus Torvalds 已提交
871 872 873 874 875 876 877 878 879 880
	if (copy_from_user(page, buf, count))
		goto out;

	length = -EINVAL;
	if (sscanf(page, "%d", &new_value) != 1)
		goto out;

	if (new_value)
		new_value = 1;

S
Stephen Smalley 已提交
881
	bool_pending_values[index] = new_value;
L
Linus Torvalds 已提交
882 883 884
	length = count;

out:
I
Ingo Molnar 已提交
885
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
886 887 888 889 890
	if (page)
		free_page((unsigned long) page);
	return length;
}

891
static const struct file_operations sel_bool_ops = {
892 893
	.read		= sel_read_bool,
	.write		= sel_write_bool,
A
Arnd Bergmann 已提交
894
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
895 896 897 898 899 900 901
};

static ssize_t sel_commit_bools_write(struct file *filep,
				      const char __user *buf,
				      size_t count, loff_t *ppos)
{
	char *page = NULL;
S
Stephen Smalley 已提交
902
	ssize_t length;
L
Linus Torvalds 已提交
903 904
	int new_value;

I
Ingo Molnar 已提交
905
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
906 907 908 909 910

	length = task_has_security(current, SECURITY__SETBOOL);
	if (length)
		goto out;

911
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
912 913 914 915 916 917 918
		length = -ENOMEM;
		goto out;
	}
	if (*ppos != 0) {
		/* No partial writes. */
		goto out;
	}
919
	page = (char *)get_zeroed_page(GFP_KERNEL);
L
Linus Torvalds 已提交
920 921 922 923 924
	if (!page) {
		length = -ENOMEM;
		goto out;
	}

S
Stephen Smalley 已提交
925
	length = -EFAULT;
L
Linus Torvalds 已提交
926 927 928 929 930 931 932
	if (copy_from_user(page, buf, count))
		goto out;

	length = -EINVAL;
	if (sscanf(page, "%d", &new_value) != 1)
		goto out;

933
	if (new_value && bool_pending_values)
L
Linus Torvalds 已提交
934 935 936 937 938
		security_set_bools(bool_num, bool_pending_values);

	length = count;

out:
I
Ingo Molnar 已提交
939
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
940 941 942 943 944
	if (page)
		free_page((unsigned long) page);
	return length;
}

945
static const struct file_operations sel_commit_bools_ops = {
946
	.write		= sel_commit_bools_write,
A
Arnd Bergmann 已提交
947
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
948 949
};

950
static void sel_remove_entries(struct dentry *de)
L
Linus Torvalds 已提交
951
{
952
	struct list_head *node;
L
Linus Torvalds 已提交
953 954 955 956

	spin_lock(&dcache_lock);
	node = de->d_subdirs.next;
	while (node != &de->d_subdirs) {
E
Eric Dumazet 已提交
957
		struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
L
Linus Torvalds 已提交
958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989
		list_del_init(node);

		if (d->d_inode) {
			d = dget_locked(d);
			spin_unlock(&dcache_lock);
			d_delete(d);
			simple_unlink(de->d_inode, d);
			dput(d);
			spin_lock(&dcache_lock);
		}
		node = de->d_subdirs.next;
	}

	spin_unlock(&dcache_lock);
}

#define BOOL_DIR_NAME "booleans"

static int sel_make_bools(void)
{
	int i, ret = 0;
	ssize_t len;
	struct dentry *dentry = NULL;
	struct dentry *dir = bool_dir;
	struct inode *inode = NULL;
	struct inode_security_struct *isec;
	char **names = NULL, *page;
	int num;
	int *values = NULL;
	u32 sid;

	/* remove any existing files */
990 991
	for (i = 0; i < bool_num; i++)
		kfree(bool_pending_names[i]);
S
Stephen Smalley 已提交
992
	kfree(bool_pending_names);
J
Jesper Juhl 已提交
993
	kfree(bool_pending_values);
S
Stephen Smalley 已提交
994
	bool_pending_names = NULL;
995
	bool_pending_values = NULL;
L
Linus Torvalds 已提交
996

997
	sel_remove_entries(dir);
L
Linus Torvalds 已提交
998

999 1000
	page = (char *)get_zeroed_page(GFP_KERNEL);
	if (!page)
L
Linus Torvalds 已提交
1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026
		return -ENOMEM;

	ret = security_get_bools(&num, &names, &values);
	if (ret != 0)
		goto out;

	for (i = 0; i < num; i++) {
		dentry = d_alloc_name(dir, names[i]);
		if (!dentry) {
			ret = -ENOMEM;
			goto err;
		}
		inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
		if (!inode) {
			ret = -ENOMEM;
			goto err;
		}

		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
		if (len < 0) {
			ret = -EINVAL;
			goto err;
		} else if (len >= PAGE_SIZE) {
			ret = -ENAMETOOLONG;
			goto err;
		}
1027 1028 1029
		isec = (struct inode_security_struct *)inode->i_security;
		ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
		if (ret)
L
Linus Torvalds 已提交
1030 1031 1032 1033
			goto err;
		isec->sid = sid;
		isec->initialized = 1;
		inode->i_fop = &sel_bool_ops;
1034
		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
L
Linus Torvalds 已提交
1035 1036 1037
		d_add(dentry, inode);
	}
	bool_num = num;
S
Stephen Smalley 已提交
1038
	bool_pending_names = names;
L
Linus Torvalds 已提交
1039 1040 1041
	bool_pending_values = values;
out:
	free_page((unsigned long)page);
S
Stephen Smalley 已提交
1042 1043
	return ret;
err:
L
Linus Torvalds 已提交
1044
	if (names) {
J
Jesper Juhl 已提交
1045 1046
		for (i = 0; i < num; i++)
			kfree(names[i]);
L
Linus Torvalds 已提交
1047 1048
		kfree(names);
	}
1049
	kfree(values);
1050
	sel_remove_entries(dir);
L
Linus Torvalds 已提交
1051 1052 1053 1054 1055 1056
	ret = -ENOMEM;
	goto out;
}

#define NULL_FILE_NAME "null"

1057
struct dentry *selinux_null;
L
Linus Torvalds 已提交
1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068

static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
					    size_t count, loff_t *ppos)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t length;

	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

1069 1070
static ssize_t sel_write_avc_cache_threshold(struct file *file,
					     const char __user *buf,
L
Linus Torvalds 已提交
1071 1072 1073 1074 1075 1076 1077
					     size_t count, loff_t *ppos)

{
	char *page;
	ssize_t ret;
	int new_value;

1078
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
		ret = -ENOMEM;
		goto out;
	}

	if (*ppos != 0) {
		/* No partial writes. */
		ret = -EINVAL;
		goto out;
	}

1089
	page = (char *)get_zeroed_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}

	if (copy_from_user(page, buf, count)) {
		ret = -EFAULT;
		goto out_free;
	}

	if (sscanf(page, "%u", &new_value) != 1) {
		ret = -EINVAL;
		goto out;
	}

	if (new_value != avc_cache_threshold) {
		ret = task_has_security(current, SECURITY__SETSECPARAM);
		if (ret)
			goto out_free;
		avc_cache_threshold = new_value;
	}
	ret = count;
out_free:
	free_page((unsigned long)page);
out:
	return ret;
}

static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
				       size_t count, loff_t *ppos)
{
	char *page;
	ssize_t ret = 0;

	page = (char *)__get_free_page(GFP_KERNEL);
	if (!page) {
		ret = -ENOMEM;
		goto out;
	}
	ret = avc_get_hash_stats(page);
	if (ret >= 0)
		ret = simple_read_from_buffer(buf, count, ppos, page, ret);
	free_page((unsigned long)page);
out:
	return ret;
}

1137
static const struct file_operations sel_avc_cache_threshold_ops = {
L
Linus Torvalds 已提交
1138 1139
	.read		= sel_read_avc_cache_threshold,
	.write		= sel_write_avc_cache_threshold,
A
Arnd Bergmann 已提交
1140
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
1141 1142
};

1143
static const struct file_operations sel_avc_hash_stats_ops = {
L
Linus Torvalds 已提交
1144
	.read		= sel_read_avc_hash_stats,
A
Arnd Bergmann 已提交
1145
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
1146 1147 1148 1149 1150 1151 1152
};

#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
{
	int cpu;

1153
	for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
L
Linus Torvalds 已提交
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
		if (!cpu_possible(cpu))
			continue;
		*idx = cpu + 1;
		return &per_cpu(avc_cache_stats, cpu);
	}
	return NULL;
}

static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
{
	loff_t n = *pos - 1;

	if (*pos == 0)
		return SEQ_START_TOKEN;

	return sel_avc_get_stat_idx(&n);
}

static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	return sel_avc_get_stat_idx(pos);
}

static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
{
	struct avc_cache_stats *st = v;

	if (v == SEQ_START_TOKEN)
		seq_printf(seq, "lookups hits misses allocations reclaims "
			   "frees\n");
	else
		seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
			   st->hits, st->misses, st->allocations,
			   st->reclaims, st->frees);
	return 0;
}

static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
{ }

1194
static const struct seq_operations sel_avc_cache_stats_seq_ops = {
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Linus Torvalds 已提交
1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
	.start		= sel_avc_stats_seq_start,
	.next		= sel_avc_stats_seq_next,
	.show		= sel_avc_stats_seq_show,
	.stop		= sel_avc_stats_seq_stop,
};

static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
{
	return seq_open(file, &sel_avc_cache_stats_seq_ops);
}

1206
static const struct file_operations sel_avc_cache_stats_ops = {
L
Linus Torvalds 已提交
1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
	.open		= sel_open_avc_cache_stats,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};
#endif

static int sel_make_avc_files(struct dentry *dir)
{
	int i, ret = 0;
	static struct tree_descr files[] = {
		{ "cache_threshold",
		  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
		{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
		{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
#endif
	};

1226
	for (i = 0; i < ARRAY_SIZE(files); i++) {
L
Linus Torvalds 已提交
1227 1228 1229 1230 1231 1232
		struct inode *inode;
		struct dentry *dentry;

		dentry = d_alloc_name(dir, files[i].name);
		if (!dentry) {
			ret = -ENOMEM;
1233
			goto out;
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1234 1235 1236 1237 1238
		}

		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
		if (!inode) {
			ret = -ENOMEM;
1239
			goto out;
L
Linus Torvalds 已提交
1240 1241
		}
		inode->i_fop = files[i].ops;
1242
		inode->i_ino = ++sel_last_ino;
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Linus Torvalds 已提交
1243 1244 1245 1246 1247 1248
		d_add(dentry, inode);
	}
out:
	return ret;
}

1249
static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269
				size_t count, loff_t *ppos)
{
	struct inode *inode;
	char *con;
	u32 sid, len;
	ssize_t ret;

	inode = file->f_path.dentry->d_inode;
	sid = inode->i_ino&SEL_INO_MASK;
	ret = security_sid_to_context(sid, &con, &len);
	if (ret < 0)
		return ret;

	ret = simple_read_from_buffer(buf, count, ppos, con, len);
	kfree(con);
	return ret;
}

static const struct file_operations sel_initcon_ops = {
	.read		= sel_read_initcon,
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Arnd Bergmann 已提交
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	.llseek		= generic_file_llseek,
1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298
};

static int sel_make_initcon_files(struct dentry *dir)
{
	int i, ret = 0;

	for (i = 1; i <= SECINITSID_NUM; i++) {
		struct inode *inode;
		struct dentry *dentry;
		dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
		if (!dentry) {
			ret = -ENOMEM;
			goto out;
		}

		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
		if (!inode) {
			ret = -ENOMEM;
			goto out;
		}
		inode->i_fop = &sel_initcon_ops;
		inode->i_ino = i|SEL_INITCON_INO_OFFSET;
		d_add(dentry, inode);
	}
out:
	return ret;
}

1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323
static inline unsigned int sel_div(unsigned long a, unsigned long b)
{
	return a / b - (a % b < 0);
}

static inline unsigned long sel_class_to_ino(u16 class)
{
	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
}

static inline u16 sel_ino_to_class(unsigned long ino)
{
	return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
}

static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
{
	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
}

static inline u32 sel_ino_to_perm(unsigned long ino)
{
	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
}

1324
static ssize_t sel_read_class(struct file *file, char __user *buf,
1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345
				size_t count, loff_t *ppos)
{
	ssize_t rc, len;
	char *page;
	unsigned long ino = file->f_path.dentry->d_inode->i_ino;

	page = (char *)__get_free_page(GFP_KERNEL);
	if (!page) {
		rc = -ENOMEM;
		goto out;
	}

	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
	rc = simple_read_from_buffer(buf, count, ppos, page, len);
	free_page((unsigned long)page);
out:
	return rc;
}

static const struct file_operations sel_class_ops = {
	.read		= sel_read_class,
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Arnd Bergmann 已提交
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	.llseek		= generic_file_llseek,
1347 1348
};

1349
static ssize_t sel_read_perm(struct file *file, char __user *buf,
1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361
				size_t count, loff_t *ppos)
{
	ssize_t rc, len;
	char *page;
	unsigned long ino = file->f_path.dentry->d_inode->i_ino;

	page = (char *)__get_free_page(GFP_KERNEL);
	if (!page) {
		rc = -ENOMEM;
		goto out;
	}

1362
	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1363 1364 1365 1366 1367 1368 1369 1370
	rc = simple_read_from_buffer(buf, count, ppos, page, len);
	free_page((unsigned long)page);
out:
	return rc;
}

static const struct file_operations sel_perm_ops = {
	.read		= sel_read_perm,
A
Arnd Bergmann 已提交
1371
	.llseek		= generic_file_llseek,
1372 1373
};

1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389
static ssize_t sel_read_policycap(struct file *file, char __user *buf,
				  size_t count, loff_t *ppos)
{
	int value;
	char tmpbuf[TMPBUFLEN];
	ssize_t length;
	unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;

	value = security_policycap_supported(i_ino & SEL_INO_MASK);
	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);

	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}

static const struct file_operations sel_policycap_ops = {
	.read		= sel_read_policycap,
A
Arnd Bergmann 已提交
1390
	.llseek		= generic_file_llseek,
1391 1392
};

1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419
static int sel_make_perm_files(char *objclass, int classvalue,
				struct dentry *dir)
{
	int i, rc = 0, nperms;
	char **perms;

	rc = security_get_permissions(objclass, &perms, &nperms);
	if (rc)
		goto out;

	for (i = 0; i < nperms; i++) {
		struct inode *inode;
		struct dentry *dentry;

		dentry = d_alloc_name(dir, perms[i]);
		if (!dentry) {
			rc = -ENOMEM;
			goto out1;
		}

		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
		if (!inode) {
			rc = -ENOMEM;
			goto out1;
		}
		inode->i_fop = &sel_perm_ops;
		/* i+1 since perm values are 1-indexed */
1420
		inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507
		d_add(dentry, inode);
	}

out1:
	for (i = 0; i < nperms; i++)
		kfree(perms[i]);
	kfree(perms);
out:
	return rc;
}

static int sel_make_class_dir_entries(char *classname, int index,
					struct dentry *dir)
{
	struct dentry *dentry = NULL;
	struct inode *inode = NULL;
	int rc;

	dentry = d_alloc_name(dir, "index");
	if (!dentry) {
		rc = -ENOMEM;
		goto out;
	}

	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
	if (!inode) {
		rc = -ENOMEM;
		goto out;
	}

	inode->i_fop = &sel_class_ops;
	inode->i_ino = sel_class_to_ino(index);
	d_add(dentry, inode);

	dentry = d_alloc_name(dir, "perms");
	if (!dentry) {
		rc = -ENOMEM;
		goto out;
	}

	rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
	if (rc)
		goto out;

	rc = sel_make_perm_files(classname, index, dentry);

out:
	return rc;
}

static void sel_remove_classes(void)
{
	struct list_head *class_node;

	list_for_each(class_node, &class_dir->d_subdirs) {
		struct dentry *class_subdir = list_entry(class_node,
					struct dentry, d_u.d_child);
		struct list_head *class_subdir_node;

		list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
			struct dentry *d = list_entry(class_subdir_node,
						struct dentry, d_u.d_child);

			if (d->d_inode)
				if (d->d_inode->i_mode & S_IFDIR)
					sel_remove_entries(d);
		}

		sel_remove_entries(class_subdir);
	}

	sel_remove_entries(class_dir);
}

static int sel_make_classes(void)
{
	int rc = 0, nclasses, i;
	char **classes;

	/* delete any existing entries */
	sel_remove_classes();

	rc = security_get_classes(&classes, &nclasses);
	if (rc < 0)
		goto out;

	/* +2 since classes are 1-indexed */
1508
	last_class_ino = sel_class_to_ino(nclasses + 2);
1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524

	for (i = 0; i < nclasses; i++) {
		struct dentry *class_name_dir;

		class_name_dir = d_alloc_name(class_dir, classes[i]);
		if (!class_name_dir) {
			rc = -ENOMEM;
			goto out1;
		}

		rc = sel_make_dir(class_dir->d_inode, class_name_dir,
				&last_class_ino);
		if (rc)
			goto out1;

		/* i+1 since class values are 1-indexed */
1525
		rc = sel_make_class_dir_entries(classes[i], i + 1,
1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538
				class_name_dir);
		if (rc)
			goto out1;
	}

out1:
	for (i = 0; i < nclasses; i++)
		kfree(classes[i]);
	kfree(classes);
out:
	return rc;
}

1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568
static int sel_make_policycap(void)
{
	unsigned int iter;
	struct dentry *dentry = NULL;
	struct inode *inode = NULL;

	sel_remove_entries(policycap_dir);

	for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
		if (iter < ARRAY_SIZE(policycap_names))
			dentry = d_alloc_name(policycap_dir,
					      policycap_names[iter]);
		else
			dentry = d_alloc_name(policycap_dir, "unknown");

		if (dentry == NULL)
			return -ENOMEM;

		inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
		if (inode == NULL)
			return -ENOMEM;

		inode->i_fop = &sel_policycap_ops;
		inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
		d_add(dentry, inode);
	}

	return 0;
}

1569 1570
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
			unsigned long *ino)
L
Linus Torvalds 已提交
1571 1572 1573 1574
{
	int ret = 0;
	struct inode *inode;

1575
	inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
L
Linus Torvalds 已提交
1576 1577 1578 1579 1580 1581
	if (!inode) {
		ret = -ENOMEM;
		goto out;
	}
	inode->i_op = &simple_dir_inode_operations;
	inode->i_fop = &simple_dir_operations;
1582
	inode->i_ino = ++(*ino);
1583
	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1584
	inc_nlink(inode);
L
Linus Torvalds 已提交
1585
	d_add(dentry, inode);
1586
	/* bump link count on parent directory, too */
1587
	inc_nlink(dir);
L
Linus Torvalds 已提交
1588 1589 1590 1591
out:
	return ret;
}

1592
static int sel_fill_super(struct super_block *sb, void *data, int silent)
L
Linus Torvalds 已提交
1593 1594 1595
{
	int ret;
	struct dentry *dentry;
1596
	struct inode *inode, *root_inode;
L
Linus Torvalds 已提交
1597 1598 1599 1600 1601
	struct inode_security_struct *isec;

	static struct tree_descr selinux_files[] = {
		[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
		[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1602
		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
L
Linus Torvalds 已提交
1603 1604 1605 1606 1607 1608 1609 1610 1611 1612
		[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
		[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
		[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
		[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
		[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
		[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
		[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
		[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
		[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
		[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1613 1614
		[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
		[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
L
Linus Torvalds 已提交
1615 1616 1617 1618
		/* last one */ {""}
	};
	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
	if (ret)
1619
		goto err;
L
Linus Torvalds 已提交
1620

1621 1622
	root_inode = sb->s_root->d_inode;

L
Linus Torvalds 已提交
1623
	dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1624 1625 1626 1627
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
Linus Torvalds 已提交
1628

1629
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1630
	if (ret)
1631
		goto err;
1632

L
Linus Torvalds 已提交
1633 1634 1635
	bool_dir = dentry;

	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1636 1637 1638 1639
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
Linus Torvalds 已提交
1640 1641

	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1642 1643 1644 1645
	if (!inode) {
		ret = -ENOMEM;
		goto err;
	}
1646
	inode->i_ino = ++sel_last_ino;
1647
	isec = (struct inode_security_struct *)inode->i_security;
L
Linus Torvalds 已提交
1648 1649 1650 1651 1652 1653 1654 1655 1656
	isec->sid = SECINITSID_DEVNULL;
	isec->sclass = SECCLASS_CHR_FILE;
	isec->initialized = 1;

	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
	d_add(dentry, inode);
	selinux_null = dentry;

	dentry = d_alloc_name(sb->s_root, "avc");
1657 1658 1659 1660
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
Linus Torvalds 已提交
1661

1662
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
L
Linus Torvalds 已提交
1663
	if (ret)
1664
		goto err;
L
Linus Torvalds 已提交
1665 1666 1667

	ret = sel_make_avc_files(dentry);
	if (ret)
1668
		goto err;
1669 1670 1671 1672 1673 1674 1675

	dentry = d_alloc_name(sb->s_root, "initial_contexts");
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}

1676
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1677 1678 1679 1680 1681 1682 1683
	if (ret)
		goto err;

	ret = sel_make_initcon_files(dentry);
	if (ret)
		goto err;

1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695
	dentry = d_alloc_name(sb->s_root, "class");
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}

	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
	if (ret)
		goto err;

	class_dir = dentry;

1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707
	dentry = d_alloc_name(sb->s_root, "policy_capabilities");
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}

	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
	if (ret)
		goto err;

	policycap_dir = dentry;

L
Linus Torvalds 已提交
1708
out:
1709 1710
	return ret;
err:
E
Eric Paris 已提交
1711 1712
	printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
		__func__);
1713
	goto out;
L
Linus Torvalds 已提交
1714 1715
}

1716 1717 1718
static int sel_get_sb(struct file_system_type *fs_type,
		      int flags, const char *dev_name, void *data,
		      struct vfsmount *mnt)
L
Linus Torvalds 已提交
1719
{
1720
	return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
L
Linus Torvalds 已提交
1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756
}

static struct file_system_type sel_fs_type = {
	.name		= "selinuxfs",
	.get_sb		= sel_get_sb,
	.kill_sb	= kill_litter_super,
};

struct vfsmount *selinuxfs_mount;

static int __init init_sel_fs(void)
{
	int err;

	if (!selinux_enabled)
		return 0;
	err = register_filesystem(&sel_fs_type);
	if (!err) {
		selinuxfs_mount = kern_mount(&sel_fs_type);
		if (IS_ERR(selinuxfs_mount)) {
			printk(KERN_ERR "selinuxfs:  could not mount!\n");
			err = PTR_ERR(selinuxfs_mount);
			selinuxfs_mount = NULL;
		}
	}
	return err;
}

__initcall(init_sel_fs);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
void exit_sel_fs(void)
{
	unregister_filesystem(&sel_fs_type);
}
#endif