selinuxfs.c 39.8 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_STATUS,	/* export current status using mmap() */
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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);
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		selinux_status_update_setenforce(selinux_enforcing);
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	}
	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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static int sel_open_handle_status(struct inode *inode, struct file *filp)
{
	struct page    *status = selinux_kernel_status_page();

	if (!status)
		return -ENOMEM;

	filp->private_data = status;

	return 0;
}

static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
				      size_t count, loff_t *ppos)
{
	struct page    *status = filp->private_data;

	BUG_ON(!status);

	return simple_read_from_buffer(buf, count, ppos,
				       page_address(status),
				       sizeof(struct selinux_kernel_status));
}

static int sel_mmap_handle_status(struct file *filp,
				  struct vm_area_struct *vma)
{
	struct page    *status = filp->private_data;
	unsigned long	size = vma->vm_end - vma->vm_start;

	BUG_ON(!status);

	/* only allows one page from the head */
	if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
		return -EIO;
	/* disallow writable mapping */
	if (vma->vm_flags & VM_WRITE)
		return -EPERM;
	/* disallow mprotect() turns it into writable */
	vma->vm_flags &= ~VM_MAYWRITE;

	return remap_pfn_range(vma, vma->vm_start,
			       page_to_pfn(status),
			       size, vma->vm_page_prot);
}

static const struct file_operations sel_handle_status_ops = {
	.open		= sel_open_handle_status,
	.read		= sel_read_handle_status,
	.mmap		= sel_mmap_handle_status,
	.llseek		= generic_file_llseek,
};

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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;
584
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
585 586 587
	if (length < 0)
		goto out2;

588
	security_compute_av_user(ssid, tsid, tclass, &avd);
L
Linus Torvalds 已提交
589 590

	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
591
			  "%x %x %x %x %u %x",
592
			  avd.allowed, 0xffffffff,
L
Linus Torvalds 已提交
593
			  avd.auditallow, avd.auditdeny,
594
			  avd.seqno, avd.flags);
L
Linus Torvalds 已提交
595 596 597 598 599 600 601
out2:
	kfree(tcon);
out:
	kfree(scon);
	return length;
}

602
static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
603 604 605 606 607 608 609 610 611 612 613 614 615
{
	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;
616
	scon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
617 618 619
	if (!scon)
		return length;

620
	tcon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
621 622 623 624 625 626 627
	if (!tcon)
		goto out;

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

628
	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
L
Linus Torvalds 已提交
629 630
	if (length < 0)
		goto out2;
631
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
632 633 634
	if (length < 0)
		goto out2;

635
	length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
L
Linus Torvalds 已提交
636 637 638 639 640 641 642 643
	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
644 645
		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
L
Linus Torvalds 已提交
646 647 648 649 650 651 652 653 654 655 656 657 658 659 660
		length = -ERANGE;
		goto out3;
	}

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

661
static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
662 663 664 665 666 667 668 669 670 671 672 673 674
{
	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;
675
	scon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
676 677 678
	if (!scon)
		return length;

679
	tcon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
680 681 682 683 684 685 686
	if (!tcon)
		goto out;

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

687
	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
L
Linus Torvalds 已提交
688 689
	if (length < 0)
		goto out2;
690
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
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
	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;
}

718
static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
719 720 721 722 723 724 725 726 727 728 729 730 731
{
	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;
732
	con = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
733 734 735
	if (!con)
		return length;

736
	user = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
737 738 739 740 741 742 743
	if (!user)
		goto out;

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

744
	length = security_context_to_sid(con, strlen(con) + 1, &sid);
L
Linus Torvalds 已提交
745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778
	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;
}

779
static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
L
Linus Torvalds 已提交
780 781 782 783 784 785 786 787 788 789 790 791 792
{
	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;
793
	scon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
794 795 796
	if (!scon)
		return length;

797
	tcon = kzalloc(size + 1, GFP_KERNEL);
L
Linus Torvalds 已提交
798 799 800 801 802 803 804
	if (!tcon)
		goto out;

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

805
	length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
L
Linus Torvalds 已提交
806 807
	if (length < 0)
		goto out2;
808
	length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
L
Linus Torvalds 已提交
809 810 811 812 813 814 815 816 817 818 819 820
	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
821 822
		printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
			"payload max\n", __func__, len);
L
Linus Torvalds 已提交
823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855
		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
856 857 858
	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
859

I
Ingo Molnar 已提交
860
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
861

S
Stephen Smalley 已提交
862 863 864 865
	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
		ret = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
866

867 868
	page = (char *)get_zeroed_page(GFP_KERNEL);
	if (!page) {
L
Linus Torvalds 已提交
869 870 871 872
		ret = -ENOMEM;
		goto out;
	}

S
Stephen Smalley 已提交
873
	cur_enforcing = security_get_bool_value(index);
L
Linus Torvalds 已提交
874 875 876 877 878
	if (cur_enforcing < 0) {
		ret = cur_enforcing;
		goto out;
	}
	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
S
Stephen Smalley 已提交
879
			  bool_pending_values[index]);
880
	ret = simple_read_from_buffer(buf, count, ppos, page, length);
L
Linus Torvalds 已提交
881
out:
I
Ingo Molnar 已提交
882
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
883 884 885 886 887 888 889 890 891
	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
892
	ssize_t length;
L
Linus Torvalds 已提交
893
	int new_value;
S
Stephen Smalley 已提交
894 895 896
	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
897

I
Ingo Molnar 已提交
898
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
899 900 901 902 903

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

S
Stephen Smalley 已提交
904 905 906 907 908
	if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
		length = -EINVAL;
		goto out;
	}

909
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
910 911 912
		length = -ENOMEM;
		goto out;
	}
S
Stephen Smalley 已提交
913

L
Linus Torvalds 已提交
914 915
	if (*ppos != 0) {
		/* No partial writes. */
S
Stephen Smalley 已提交
916
		length = -EINVAL;
L
Linus Torvalds 已提交
917 918
		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
926 927 928 929 930 931 932 933 934 935
	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
936
	bool_pending_values[index] = new_value;
L
Linus Torvalds 已提交
937 938 939
	length = count;

out:
I
Ingo Molnar 已提交
940
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
941 942 943 944 945
	if (page)
		free_page((unsigned long) page);
	return length;
}

946
static const struct file_operations sel_bool_ops = {
947 948
	.read		= sel_read_bool,
	.write		= sel_write_bool,
A
Arnd Bergmann 已提交
949
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
950 951 952 953 954 955 956
};

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
957
	ssize_t length;
L
Linus Torvalds 已提交
958 959
	int new_value;

I
Ingo Molnar 已提交
960
	mutex_lock(&sel_mutex);
L
Linus Torvalds 已提交
961 962 963 964 965

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

966
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
967 968 969 970 971 972 973
		length = -ENOMEM;
		goto out;
	}
	if (*ppos != 0) {
		/* No partial writes. */
		goto out;
	}
974
	page = (char *)get_zeroed_page(GFP_KERNEL);
L
Linus Torvalds 已提交
975 976 977 978 979
	if (!page) {
		length = -ENOMEM;
		goto out;
	}

S
Stephen Smalley 已提交
980
	length = -EFAULT;
L
Linus Torvalds 已提交
981 982 983 984 985 986 987
	if (copy_from_user(page, buf, count))
		goto out;

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

988
	if (new_value && bool_pending_values)
L
Linus Torvalds 已提交
989 990 991 992 993
		security_set_bools(bool_num, bool_pending_values);

	length = count;

out:
I
Ingo Molnar 已提交
994
	mutex_unlock(&sel_mutex);
L
Linus Torvalds 已提交
995 996 997 998 999
	if (page)
		free_page((unsigned long) page);
	return length;
}

1000
static const struct file_operations sel_commit_bools_ops = {
1001
	.write		= sel_commit_bools_write,
A
Arnd Bergmann 已提交
1002
	.llseek		= generic_file_llseek,
L
Linus Torvalds 已提交
1003 1004
};

1005
static void sel_remove_entries(struct dentry *de)
L
Linus Torvalds 已提交
1006
{
1007
	struct list_head *node;
L
Linus Torvalds 已提交
1008 1009 1010 1011

	spin_lock(&dcache_lock);
	node = de->d_subdirs.next;
	while (node != &de->d_subdirs) {
E
Eric Dumazet 已提交
1012
		struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
L
Linus Torvalds 已提交
1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044
		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 */
1045 1046
	for (i = 0; i < bool_num; i++)
		kfree(bool_pending_names[i]);
S
Stephen Smalley 已提交
1047
	kfree(bool_pending_names);
J
Jesper Juhl 已提交
1048
	kfree(bool_pending_values);
S
Stephen Smalley 已提交
1049
	bool_pending_names = NULL;
1050
	bool_pending_values = NULL;
L
Linus Torvalds 已提交
1051

1052
	sel_remove_entries(dir);
L
Linus Torvalds 已提交
1053

1054 1055
	page = (char *)get_zeroed_page(GFP_KERNEL);
	if (!page)
L
Linus Torvalds 已提交
1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081
		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;
		}
1082 1083 1084
		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
1085 1086 1087 1088
			goto err;
		isec->sid = sid;
		isec->initialized = 1;
		inode->i_fop = &sel_bool_ops;
1089
		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
L
Linus Torvalds 已提交
1090 1091 1092
		d_add(dentry, inode);
	}
	bool_num = num;
S
Stephen Smalley 已提交
1093
	bool_pending_names = names;
L
Linus Torvalds 已提交
1094 1095 1096
	bool_pending_values = values;
out:
	free_page((unsigned long)page);
S
Stephen Smalley 已提交
1097 1098
	return ret;
err:
L
Linus Torvalds 已提交
1099
	if (names) {
J
Jesper Juhl 已提交
1100 1101
		for (i = 0; i < num; i++)
			kfree(names[i]);
L
Linus Torvalds 已提交
1102 1103
		kfree(names);
	}
1104
	kfree(values);
1105
	sel_remove_entries(dir);
L
Linus Torvalds 已提交
1106 1107 1108 1109 1110 1111
	ret = -ENOMEM;
	goto out;
}

#define NULL_FILE_NAME "null"

1112
struct dentry *selinux_null;
L
Linus Torvalds 已提交
1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123

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);
}

1124 1125
static ssize_t sel_write_avc_cache_threshold(struct file *file,
					     const char __user *buf,
L
Linus Torvalds 已提交
1126 1127 1128 1129 1130 1131 1132
					     size_t count, loff_t *ppos)

{
	char *page;
	ssize_t ret;
	int new_value;

1133
	if (count >= PAGE_SIZE) {
L
Linus Torvalds 已提交
1134 1135 1136 1137 1138 1139 1140 1141 1142 1143
		ret = -ENOMEM;
		goto out;
	}

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

1144
	page = (char *)get_zeroed_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1145 1146 1147 1148 1149 1150 1151 1152 1153 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
	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;
}

1192
static const struct file_operations sel_avc_cache_threshold_ops = {
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	.read		= sel_read_avc_cache_threshold,
	.write		= sel_write_avc_cache_threshold,
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	.llseek		= generic_file_llseek,
L
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};

1198
static const struct file_operations sel_avc_hash_stats_ops = {
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	.read		= sel_read_avc_hash_stats,
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	.llseek		= generic_file_llseek,
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};

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

1208
	for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
L
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1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248
		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)
{ }

1249
static const struct seq_operations sel_avc_cache_stats_seq_ops = {
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1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260
	.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);
}

1261
static const struct file_operations sel_avc_cache_stats_ops = {
L
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	.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
	};

1281
	for (i = 0; i < ARRAY_SIZE(files); i++) {
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		struct inode *inode;
		struct dentry *dentry;

		dentry = d_alloc_name(dir, files[i].name);
		if (!dentry) {
			ret = -ENOMEM;
1288
			goto out;
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1289 1290 1291 1292 1293
		}

		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
		if (!inode) {
			ret = -ENOMEM;
1294
			goto out;
L
Linus Torvalds 已提交
1295 1296
		}
		inode->i_fop = files[i].ops;
1297
		inode->i_ino = ++sel_last_ino;
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		d_add(dentry, inode);
	}
out:
	return ret;
}

1304
static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324
				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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	.llseek		= generic_file_llseek,
1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353
};

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;
}

1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378
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);
}

1379
static ssize_t sel_read_class(struct file *file, char __user *buf,
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400
				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,
1402 1403
};

1404
static ssize_t sel_read_perm(struct file *file, char __user *buf,
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416
				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;
	}

1417
	len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1418 1419 1420 1421 1422 1423 1424 1425
	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,
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	.llseek		= generic_file_llseek,
1427 1428
};

1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444
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
1445
	.llseek		= generic_file_llseek,
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
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 */
1475
		inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
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 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562
		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 */
1563
	last_class_ino = sel_class_to_ino(nclasses + 2);
1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579

	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 */
1580
		rc = sel_make_class_dir_entries(classes[i], i + 1,
1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593
				class_name_dir);
		if (rc)
			goto out1;
	}

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

1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623
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;
}

1624 1625
static int sel_make_dir(struct inode *dir, struct dentry *dentry,
			unsigned long *ino)
L
Linus Torvalds 已提交
1626 1627 1628 1629
{
	int ret = 0;
	struct inode *inode;

1630
	inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
L
Linus Torvalds 已提交
1631 1632 1633 1634 1635 1636
	if (!inode) {
		ret = -ENOMEM;
		goto out;
	}
	inode->i_op = &simple_dir_inode_operations;
	inode->i_fop = &simple_dir_operations;
1637
	inode->i_ino = ++(*ino);
1638
	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1639
	inc_nlink(inode);
L
Linus Torvalds 已提交
1640
	d_add(dentry, inode);
1641
	/* bump link count on parent directory, too */
1642
	inc_nlink(dir);
L
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1643 1644 1645 1646
out:
	return ret;
}

1647
static int sel_fill_super(struct super_block *sb, void *data, int silent)
L
Linus Torvalds 已提交
1648 1649 1650
{
	int ret;
	struct dentry *dentry;
1651
	struct inode *inode, *root_inode;
L
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1652 1653 1654 1655 1656
	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},
1657
		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
L
Linus Torvalds 已提交
1658 1659 1660 1661 1662 1663 1664 1665 1666 1667
		[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},
1668 1669
		[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
		[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1670
		[SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
L
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1671 1672 1673 1674
		/* last one */ {""}
	};
	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
	if (ret)
1675
		goto err;
L
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1676

1677 1678
	root_inode = sb->s_root->d_inode;

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1679
	dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1680 1681 1682 1683
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
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1684

1685
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1686
	if (ret)
1687
		goto err;
1688

L
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1689 1690 1691
	bool_dir = dentry;

	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1692 1693 1694 1695
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
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1696 1697

	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1698 1699 1700 1701
	if (!inode) {
		ret = -ENOMEM;
		goto err;
	}
1702
	inode->i_ino = ++sel_last_ino;
1703
	isec = (struct inode_security_struct *)inode->i_security;
L
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1704 1705 1706 1707 1708 1709 1710 1711 1712
	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");
1713 1714 1715 1716
	if (!dentry) {
		ret = -ENOMEM;
		goto err;
	}
L
Linus Torvalds 已提交
1717

1718
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
L
Linus Torvalds 已提交
1719
	if (ret)
1720
		goto err;
L
Linus Torvalds 已提交
1721 1722 1723

	ret = sel_make_avc_files(dentry);
	if (ret)
1724
		goto err;
1725 1726 1727 1728 1729 1730 1731

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

1732
	ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1733 1734 1735 1736 1737 1738 1739
	if (ret)
		goto err;

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

1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751
	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;

1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
	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
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out:
1765 1766
	return ret;
err:
E
Eric Paris 已提交
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	printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
		__func__);
1769
	goto out;
L
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}

1772 1773 1774
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
1775
{
1776
	return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
L
Linus Torvalds 已提交
1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812
}

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