hooks.c 139.3 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
 *	Paul Moore <paul.moore@hp.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/proc_fs.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <asm/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/sysctl.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#define XATTR_SELINUX_SUFFIX "selinux"
#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX

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#define NUM_SEL_MNT_OPTS 5
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extern unsigned int policydb_loaded_version;
extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);

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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

static int __init selinux_enabled_setup(char *str)
{
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	unsigned long enabled;
	if (!strict_strtoul(str, 0, &enabled))
		selinux_enabled = enabled ? 1 : 0;
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	return 1;
}
__setup("selinux=", selinux_enabled_setup);
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#else
int selinux_enabled = 1;
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#endif


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/*
 * Minimal support for a secondary security module,
 * just to allow the use of the capability module.
 */
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static struct security_operations *secondary_ops;
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/* Lists of inode and superblock security structures initialized
   before the policy was loaded. */
static LIST_HEAD(superblock_security_head);
static DEFINE_SPINLOCK(sb_security_lock);

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static struct kmem_cache *sel_inode_cache;
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/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 * enabled, false (0) if SECMARK is disabled.
 *
 */
static int selinux_secmark_enabled(void)
{
	return (atomic_read(&selinux_secmark_refcount) > 0);
}

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/*
 * initialise the security for the init task
 */
static void cred_init_security(void)
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{
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	struct cred *cred = (struct cred *) current->real_cred;
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	struct task_security_struct *tsec;

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	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
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	if (!tsec)
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		panic("SELinux:  Failed to initialize initial task.\n");
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	tsec->osid = tsec->sid = SECINITSID_KERNEL;
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	cred->security = tsec;
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}

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/*
 * get the security ID of a set of credentials
 */
static inline u32 cred_sid(const struct cred *cred)
{
	const struct task_security_struct *tsec;

	tsec = cred->security;
	return tsec->sid;
}

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/*
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 * get the objective security ID of a task
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 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
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	sid = cred_sid(__task_cred(task));
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	rcu_read_unlock();
	return sid;
}

/*
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 * get the subjective security ID of the current task
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 */
static inline u32 current_sid(void)
{
	const struct task_security_struct *tsec = current_cred()->security;

	return tsec->sid;
}

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/* Allocate and free functions for each kind of security blob. */

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static int inode_alloc_security(struct inode *inode)
{
	struct inode_security_struct *isec;
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	u32 sid = current_sid();
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	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
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	if (!isec)
		return -ENOMEM;

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	mutex_init(&isec->lock);
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	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	isec->sclass = SECCLASS_FILE;
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	isec->task_sid = sid;
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	inode->i_security = isec;

	return 0;
}

static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec = inode->i_sb->s_security;

	spin_lock(&sbsec->isec_lock);
	if (!list_empty(&isec->list))
		list_del_init(&isec->list);
	spin_unlock(&sbsec->isec_lock);

	inode->i_security = NULL;
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	kmem_cache_free(sel_inode_cache, isec);
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}

static int file_alloc_security(struct file *file)
{
	struct file_security_struct *fsec;
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	u32 sid = current_sid();
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	fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
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	if (!fsec)
		return -ENOMEM;

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	fsec->sid = sid;
	fsec->fown_sid = sid;
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	file->f_security = fsec;

	return 0;
}

static void file_free_security(struct file *file)
{
	struct file_security_struct *fsec = file->f_security;
	file->f_security = NULL;
	kfree(fsec);
}

static int superblock_alloc_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec;

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	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
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	if (!sbsec)
		return -ENOMEM;

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	mutex_init(&sbsec->lock);
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	INIT_LIST_HEAD(&sbsec->list);
	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
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	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
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	sb->s_security = sbsec;

	return 0;
}

static void superblock_free_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

	spin_lock(&sb_security_lock);
	if (!list_empty(&sbsec->list))
		list_del_init(&sbsec->list);
	spin_unlock(&sb_security_lock);

	sb->s_security = NULL;
	kfree(sbsec);
}

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static int sk_alloc_security(struct sock *sk, int family, gfp_t priority)
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{
	struct sk_security_struct *ssec;

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	ssec = kzalloc(sizeof(*ssec), priority);
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	if (!ssec)
		return -ENOMEM;

	ssec->peer_sid = SECINITSID_UNLABELED;
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	ssec->sid = SECINITSID_UNLABELED;
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	sk->sk_security = ssec;

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	selinux_netlbl_sk_security_reset(ssec);
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	return 0;
}

static void sk_free_security(struct sock *sk)
{
	struct sk_security_struct *ssec = sk->sk_security;

	sk->sk_security = NULL;
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	selinux_netlbl_sk_security_free(ssec);
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	kfree(ssec);
}

/* The security server must be initialized before
   any labeling or access decisions can be provided. */
extern int ss_initialized;

/* The file system's label must be initialized prior to use. */

static char *labeling_behaviors[6] = {
	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
};

static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);

static inline int inode_doinit(struct inode *inode)
{
	return inode_doinit_with_dentry(inode, NULL);
}

enum {
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	Opt_error = -1,
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	Opt_context = 1,
	Opt_fscontext = 2,
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	Opt_defcontext = 3,
	Opt_rootcontext = 4,
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	Opt_labelsupport = 5,
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};

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static const match_table_t tokens = {
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	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
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	{Opt_labelsupport, LABELSUPP_STR},
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	{Opt_error, NULL},
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};

#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"

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static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
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			const struct cred *cred)
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{
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	const struct task_security_struct *tsec = cred->security;
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	int rc;

	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELTO, NULL);
	return rc;
}

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static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
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			const struct cred *cred)
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{
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	const struct task_security_struct *tsec = cred->security;
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	int rc;
	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__ASSOCIATE, NULL);
	return rc;
}

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static int sb_finish_set_opts(struct super_block *sb)
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{
	struct superblock_security_struct *sbsec = sb->s_security;
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	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
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	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
		if (!root_inode->i_op->getxattr) {
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
			rc = -EOPNOTSUPP;
			goto out;
		}
		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
			goto out;
		}
	}
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	sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
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	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
	else
		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
		       labeling_behaviors[sbsec->behavior-1]);
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	if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
	    sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
	    sbsec->behavior == SECURITY_FS_USE_NONE ||
	    sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		sbsec->flags &= ~SE_SBLABELSUPP;

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	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
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	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		goto next_inode;
	}
	spin_unlock(&sbsec->isec_lock);
out:
	return rc;
}
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/*
 * This function should allow an FS to ask what it's mount security
 * options were so it can use those later for submounts, displaying
 * mount options, or whatever.
 */
static int selinux_get_mnt_opts(const struct super_block *sb,
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				struct security_mnt_opts *opts)
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{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
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	security_init_mnt_opts(opts);
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	if (!(sbsec->flags & SE_SBINITIALIZED))
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		return -EINVAL;
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	if (!ss_initialized)
		return -EINVAL;
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	tmp = sbsec->flags & SE_MNTMASK;
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	/* count the number of mount options for this sb */
	for (i = 0; i < 8; i++) {
		if (tmp & 0x01)
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			opts->num_mnt_opts++;
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		tmp >>= 1;
	}
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	/* Check if the Label support flag is set */
	if (sbsec->flags & SE_SBLABELSUPP)
		opts->num_mnt_opts++;
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	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
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		rc = -ENOMEM;
		goto out_free;
	}
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	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
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		rc = -ENOMEM;
		goto out_free;
	}
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	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
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	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
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	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
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	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
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		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
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	}
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	if (sbsec->flags & SE_SBLABELSUPP) {
		opts->mnt_opts[i] = NULL;
		opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
	}
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	BUG_ON(i != opts->num_mnt_opts);
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	return 0;

out_free:
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	security_free_mnt_opts(opts);
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	return rc;
}
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static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
575 576
	char mnt_flags = sbsec->flags & SE_MNTMASK;

577
	/* check if the old mount command had the same options */
578
	if (sbsec->flags & SE_SBINITIALIZED)
579 580 581 582 583 584 585
		if (!(sbsec->flags & flag) ||
		    (old_sid != new_sid))
			return 1;

	/* check if we were passed the same options twice,
	 * aka someone passed context=a,context=b
	 */
586 587
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
588 589 590
			return 1;
	return 0;
}
591

592 593 594 595
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
596 597
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
598
{
599
	const struct cred *cred = current_cred();
600 601 602
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
603 604
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
605 606
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
607 608 609
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
610 611 612 613 614 615 616 617 618 619 620 621 622 623 624

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			spin_lock(&sb_security_lock);
			if (list_empty(&sbsec->list))
				list_add(&sbsec->list, &superblock_security_head);
			spin_unlock(&sb_security_lock);
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
625 626
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
627
		goto out;
628
	}
L
Linus Torvalds 已提交
629

630 631 632 633 634 635 636 637 638 639 640
	/*
	 * Binary mount data FS will come through this function twice.  Once
	 * from an explicit call and once from the generic calls from the vfs.
	 * Since the generic VFS calls will not contain any security mount data
	 * we need to skip the double mount verification.
	 *
	 * This does open a hole in which we will not notice if the first
	 * mount using this sb set explict options and a second mount using
	 * this sb does not set any security options.  (The first options
	 * will be used for both mounts)
	 */
641
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642
	    && (num_opts == 0))
643
		goto out;
644

645 646 647 648 649 650 651
	/*
	 * parse the mount options, check if they are valid sids.
	 * also check if someone is trying to mount the same sb more
	 * than once with different security options.
	 */
	for (i = 0; i < num_opts; i++) {
		u32 sid;
652 653 654

		if (flags[i] == SE_SBLABELSUPP)
			continue;
655 656
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
657 658 659
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704
			       mount_options[i], sb->s_id, name, rc);
			goto out;
		}
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			fscontext_sid = sid;

			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
					fscontext_sid))
				goto out_double_mount;

			sbsec->flags |= FSCONTEXT_MNT;
			break;
		case CONTEXT_MNT:
			context_sid = sid;

			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
					context_sid))
				goto out_double_mount;

			sbsec->flags |= CONTEXT_MNT;
			break;
		case ROOTCONTEXT_MNT:
			rootcontext_sid = sid;

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
					rootcontext_sid))
				goto out_double_mount;

			sbsec->flags |= ROOTCONTEXT_MNT;

			break;
		case DEFCONTEXT_MNT:
			defcontext_sid = sid;

			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
					defcontext_sid))
				goto out_double_mount;

			sbsec->flags |= DEFCONTEXT_MNT;

			break;
		default:
			rc = -EINVAL;
			goto out;
L
Linus Torvalds 已提交
705
		}
706 707
	}

708
	if (sbsec->flags & SE_SBINITIALIZED) {
709
		/* previously mounted with options, but not on this attempt? */
710
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
711 712 713 714 715
			goto out_double_mount;
		rc = 0;
		goto out;
	}

716
	if (strcmp(sb->s_type->name, "proc") == 0)
717
		sbsec->flags |= SE_SBPROC;
718 719

	/* Determine the labeling behavior to use for this filesystem type. */
720
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
721 722
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
723
		       __func__, sb->s_type->name, rc);
724 725
		goto out;
	}
L
Linus Torvalds 已提交
726

727 728
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
729
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
730
		if (rc)
731
			goto out;
L
Linus Torvalds 已提交
732

733
		sbsec->sid = fscontext_sid;
734 735 736 737 738 739 740
	}

	/*
	 * Switch to using mount point labeling behavior.
	 * sets the label used on all file below the mountpoint, and will set
	 * the superblock context if not already set.
	 */
741 742
	if (context_sid) {
		if (!fscontext_sid) {
743 744
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
745
			if (rc)
746 747
				goto out;
			sbsec->sid = context_sid;
748
		} else {
749 750
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
751
			if (rc)
752
				goto out;
753
		}
754 755
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
756

757
		sbsec->mntpoint_sid = context_sid;
758
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
759 760
	}

761
	if (rootcontext_sid) {
762 763
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
764
		if (rc)
765
			goto out;
766

767 768
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
769 770
	}

771 772 773 774 775 776
	if (defcontext_sid) {
		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
777 778
		}

779 780
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
781
							     sbsec, cred);
782 783 784
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
785

786
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
787 788
	}

789
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
790
out:
791
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
792
	return rc;
793 794 795 796 797
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
	goto out;
L
Linus Torvalds 已提交
798 799
}

800 801
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
802
{
803 804
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
805

806 807 808
	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
L
Linus Torvalds 已提交
809

810 811 812 813 814 815 816 817 818 819 820 821
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
	 * mount options.  thus we can safely put this sb on the list and deal
	 * with it later
	 */
	if (!ss_initialized) {
		spin_lock(&sb_security_lock);
		if (list_empty(&newsbsec->list))
			list_add(&newsbsec->list, &superblock_security_head);
		spin_unlock(&sb_security_lock);
		return;
	}
822 823

	/* how can we clone if the old one wasn't set up?? */
824
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
825

826
	/* if fs is reusing a sb, just let its options stand... */
827
	if (newsbsec->flags & SE_SBINITIALIZED)
828 829
		return;

830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

	newsbsec->sid = oldsbsec->sid;
	newsbsec->def_sid = oldsbsec->def_sid;
	newsbsec->behavior = oldsbsec->behavior;

	if (set_context) {
		u32 sid = oldsbsec->mntpoint_sid;

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
			struct inode *newinode = newsb->s_root->d_inode;
			struct inode_security_struct *newisec = newinode->i_security;
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
849
	}
850 851 852 853 854
	if (set_rootcontext) {
		const struct inode *oldinode = oldsb->s_root->d_inode;
		const struct inode_security_struct *oldisec = oldinode->i_security;
		struct inode *newinode = newsb->s_root->d_inode;
		struct inode_security_struct *newisec = newinode->i_security;
L
Linus Torvalds 已提交
855

856
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
857 858
	}

859 860 861 862
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

863 864
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
865
{
866
	char *p;
867 868
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
869
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
870

871
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
872

873 874 875 876
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
877

878 879
		if (!*p)
			continue;
L
Linus Torvalds 已提交
880

881
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
882

883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934
		switch (token) {
		case Opt_context:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			context = match_strdup(&args[0]);
			if (!context) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_fscontext:
			if (fscontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			fscontext = match_strdup(&args[0]);
			if (!fscontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_rootcontext:
			if (rootcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			rootcontext = match_strdup(&args[0]);
			if (!rootcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_defcontext:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			defcontext = match_strdup(&args[0]);
			if (!defcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;
935 936
		case Opt_labelsupport:
			break;
937 938 939 940
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
941 942 943

		}
	}
944

945 946 947 948 949 950 951 952 953 954 955
	rc = -ENOMEM;
	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts)
		goto out_err;

	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
		kfree(opts->mnt_opts);
		goto out_err;
	}

956
	if (fscontext) {
957 958
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
959 960
	}
	if (context) {
961 962
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
963 964
	}
	if (rootcontext) {
965 966
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
967 968
	}
	if (defcontext) {
969 970
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
971 972
	}

973 974 975
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

976 977 978 979 980
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
981 982
	return rc;
}
983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009
/*
 * string mount options parsing and call set the sbsec
 */
static int superblock_doinit(struct super_block *sb, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!data)
		goto out;

	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);

	rc = selinux_parse_opts_str(options, &opts);
	if (rc)
		goto out_err;

out:
	rc = selinux_set_mnt_opts(sb, &opts);

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1010

A
Adrian Bunk 已提交
1011 1012
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1013 1014 1015 1016 1017
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1018 1019 1020 1021 1022 1023
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037

		switch (opts->mnt_opts_flags[i]) {
		case CONTEXT_MNT:
			prefix = CONTEXT_STR;
			break;
		case FSCONTEXT_MNT:
			prefix = FSCONTEXT_STR;
			break;
		case ROOTCONTEXT_MNT:
			prefix = ROOTCONTEXT_STR;
			break;
		case DEFCONTEXT_MNT:
			prefix = DEFCONTEXT_STR;
			break;
1038 1039 1040 1041
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061
		default:
			BUG();
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
		seq_puts(m, opts->mnt_opts[i]);
		if (has_comma)
			seq_putc(m, '\"');
	}
}

static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
{
	struct security_mnt_opts opts;
	int rc;

	rc = selinux_get_mnt_opts(sb, &opts);
1062 1063 1064 1065
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1066
		return rc;
1067
	}
1068 1069 1070 1071 1072 1073 1074 1075

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098
static inline u16 inode_mode_to_security_class(umode_t mode)
{
	switch (mode & S_IFMT) {
	case S_IFSOCK:
		return SECCLASS_SOCK_FILE;
	case S_IFLNK:
		return SECCLASS_LNK_FILE;
	case S_IFREG:
		return SECCLASS_FILE;
	case S_IFBLK:
		return SECCLASS_BLK_FILE;
	case S_IFDIR:
		return SECCLASS_DIR;
	case S_IFCHR:
		return SECCLASS_CHR_FILE;
	case S_IFIFO:
		return SECCLASS_FIFO_FILE;

	}

	return SECCLASS_FILE;
}

1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
static inline int default_protocol_stream(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
}

static inline int default_protocol_dgram(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
}

L
Linus Torvalds 已提交
1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
{
	switch (family) {
	case PF_UNIX:
		switch (type) {
		case SOCK_STREAM:
		case SOCK_SEQPACKET:
			return SECCLASS_UNIX_STREAM_SOCKET;
		case SOCK_DGRAM:
			return SECCLASS_UNIX_DGRAM_SOCKET;
		}
		break;
	case PF_INET:
	case PF_INET6:
		switch (type) {
		case SOCK_STREAM:
1125 1126 1127 1128
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1129
		case SOCK_DGRAM:
1130 1131 1132 1133
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1134 1135
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1136
		default:
L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142 1143 1144 1145
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
		case NETLINK_FIREWALL:
			return SECCLASS_NETLINK_FIREWALL_SOCKET;
1146
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
		case NETLINK_NFLOG:
			return SECCLASS_NETLINK_NFLOG_SOCKET;
		case NETLINK_XFRM:
			return SECCLASS_NETLINK_XFRM_SOCKET;
		case NETLINK_SELINUX:
			return SECCLASS_NETLINK_SELINUX_SOCKET;
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
		case NETLINK_IP6_FW:
			return SECCLASS_NETLINK_IP6FW_SOCKET;
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1160 1161
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1162 1163 1164 1165 1166 1167 1168
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1169 1170
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
static int selinux_proc_get_sid(struct proc_dir_entry *de,
				u16 tclass,
				u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

1184
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
	if (!buffer)
		return -ENOMEM;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (de && de != de->parent) {
		buflen -= de->namelen + 1;
		if (buflen < 0)
			break;
		end -= de->namelen;
		memcpy(end, de->name, de->namelen);
		*--end = '/';
		path = end;
		de = de->parent;
	}
	rc = security_genfs_sid("proc", path, tclass, sid);
	free_page((unsigned long)buffer);
	return rc;
}
#else
static int selinux_proc_get_sid(struct proc_dir_entry *de,
				u16 tclass,
				u32 *sid)
{
	return -EINVAL;
}
#endif

/* The inode's security attributes must be initialized before first use. */
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
{
	struct superblock_security_struct *sbsec = NULL;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid;
	struct dentry *dentry;
#define INITCONTEXTLEN 255
	char *context = NULL;
	unsigned len = 0;
	int rc = 0;

	if (isec->initialized)
		goto out;

1232
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1233
	if (isec->initialized)
1234
		goto out_unlock;
L
Linus Torvalds 已提交
1235 1236

	sbsec = inode->i_sb->s_security;
1237
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1238 1239 1240 1241 1242 1243 1244
		/* Defer initialization until selinux_complete_init,
		   after the initial policy is loaded and the security
		   server is ready to handle calls. */
		spin_lock(&sbsec->isec_lock);
		if (list_empty(&isec->list))
			list_add(&isec->list, &sbsec->isec_head);
		spin_unlock(&sbsec->isec_lock);
1245
		goto out_unlock;
L
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1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264
	}

	switch (sbsec->behavior) {
	case SECURITY_FS_USE_XATTR:
		if (!inode->i_op->getxattr) {
			isec->sid = sbsec->def_sid;
			break;
		}

		/* Need a dentry, since the xattr API requires one.
		   Life would be simpler if we could just pass the inode. */
		if (opt_dentry) {
			/* Called from d_instantiate or d_splice_alias. */
			dentry = dget(opt_dentry);
		} else {
			/* Called from selinux_complete_init, try to find a dentry. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
1265 1266 1267 1268 1269 1270 1271 1272 1273
			/*
			 * this is can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as these
			 * will get fixed up the next time we go through
			 * inode_doinit with a dentry, before these inodes could
			 * be used again by userspace.
			 */
1274
			goto out_unlock;
L
Linus Torvalds 已提交
1275 1276 1277
		}

		len = INITCONTEXTLEN;
1278
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1279 1280 1281
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1282
			goto out_unlock;
L
Linus Torvalds 已提交
1283
		}
1284
		context[len] = '\0';
L
Linus Torvalds 已提交
1285 1286 1287
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1288 1289
			kfree(context);

L
Linus Torvalds 已提交
1290 1291 1292 1293 1294
			/* Need a larger buffer.  Query for the right size. */
			rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
						   NULL, 0);
			if (rc < 0) {
				dput(dentry);
1295
				goto out_unlock;
L
Linus Torvalds 已提交
1296 1297
			}
			len = rc;
1298
			context = kmalloc(len+1, GFP_NOFS);
L
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1299 1300 1301
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1302
				goto out_unlock;
L
Linus Torvalds 已提交
1303
			}
1304
			context[len] = '\0';
L
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			rc = inode->i_op->getxattr(dentry,
						   XATTR_NAME_SELINUX,
						   context, len);
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
1312
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1313
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1314 1315
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1316
				goto out_unlock;
L
Linus Torvalds 已提交
1317 1318 1319 1320 1321
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1322
			rc = security_context_to_sid_default(context, rc, &sid,
1323 1324
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1325
			if (rc) {
1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		isec->sid = sid;
		break;
	case SECURITY_FS_USE_TASK:
		isec->sid = isec->task_sid;
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
		isec->sid = sbsec->sid;

		/* Try to obtain a transition SID. */
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		rc = security_transition_sid(isec->task_sid,
					     sbsec->sid,
					     isec->sclass,
					     &sid);
		if (rc)
1362
			goto out_unlock;
L
Linus Torvalds 已提交
1363 1364
		isec->sid = sid;
		break;
1365 1366 1367
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1368
	default:
1369
		/* Default to the fs superblock SID. */
L
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		isec->sid = sbsec->sid;

1372
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
L
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1373 1374 1375 1376 1377 1378 1379
			struct proc_inode *proci = PROC_I(inode);
			if (proci->pde) {
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
				rc = selinux_proc_get_sid(proci->pde,
							  isec->sclass,
							  &sid);
				if (rc)
1380
					goto out_unlock;
L
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1381 1382 1383 1384 1385 1386 1387 1388
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1389 1390
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
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 1420 1421 1422 1423
out:
	if (isec->sclass == SECCLASS_FILE)
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
	return rc;
}

/* Convert a Linux signal to an access vector. */
static inline u32 signal_to_av(int sig)
{
	u32 perm = 0;

	switch (sig) {
	case SIGCHLD:
		/* Commonly granted from child to parent. */
		perm = PROCESS__SIGCHLD;
		break;
	case SIGKILL:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGKILL;
		break;
	case SIGSTOP:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGSTOP;
		break;
	default:
		/* All other signals. */
		perm = PROCESS__SIGNAL;
		break;
	}

	return perm;
}

D
David Howells 已提交
1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436
/*
 * Check permission between a pair of credentials
 * fork check, ptrace check, etc.
 */
static int cred_has_perm(const struct cred *actor,
			 const struct cred *target,
			 u32 perms)
{
	u32 asid = cred_sid(actor), tsid = cred_sid(target);

	return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
}

1437
/*
1438
 * Check permission between a pair of tasks, e.g. signal checks,
1439 1440
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1441
 * - this uses the default subjective creds of tsk1
1442 1443 1444
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1445 1446
			 u32 perms)
{
1447 1448
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1449

1450 1451 1452 1453 1454
	rcu_read_lock();
	__tsec1 = __task_cred(tsk1)->security;	sid1 = __tsec1->sid;
	__tsec2 = __task_cred(tsk2)->security;	sid2 = __tsec2->sid;
	rcu_read_unlock();
	return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
L
Linus Torvalds 已提交
1455 1456
}

1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472
/*
 * Check permission between current and another task, e.g. signal checks,
 * fork check, ptrace check, etc.
 * current is the actor and tsk2 is the target
 * - this uses current's subjective creds
 */
static int current_has_perm(const struct task_struct *tsk,
			    u32 perms)
{
	u32 sid, tsid;

	sid = current_sid();
	tsid = task_sid(tsk);
	return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
}

1473 1474 1475 1476
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1477 1478
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1479
			       const struct cred *cred,
1480
			       int cap, int audit)
L
Linus Torvalds 已提交
1481
{
1482
	struct common_audit_data ad;
1483
	struct av_decision avd;
1484
	u16 sclass;
1485
	u32 sid = cred_sid(cred);
1486
	u32 av = CAP_TO_MASK(cap);
1487
	int rc;
L
Linus Torvalds 已提交
1488

1489
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
L
Linus Torvalds 已提交
1490 1491 1492
	ad.tsk = tsk;
	ad.u.cap = cap;

1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504
	switch (CAP_TO_INDEX(cap)) {
	case 0:
		sclass = SECCLASS_CAPABILITY;
		break;
	case 1:
		sclass = SECCLASS_CAPABILITY2;
		break;
	default:
		printk(KERN_ERR
		       "SELinux:  out of range capability %d\n", cap);
		BUG();
	}
1505

1506
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1507
	if (audit == SECURITY_CAP_AUDIT)
1508
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1509
	return rc;
L
Linus Torvalds 已提交
1510 1511 1512 1513 1514 1515
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1516
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1517

1518
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1519 1520 1521 1522 1523 1524
			    SECCLASS_SYSTEM, perms, NULL);
}

/* Check whether a task has a particular permission to an inode.
   The 'adp' parameter is optional and allows other audit
   data to be passed (e.g. the dentry). */
1525
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1526 1527
			  struct inode *inode,
			  u32 perms,
1528
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1529 1530
{
	struct inode_security_struct *isec;
1531
	struct common_audit_data ad;
1532
	u32 sid;
L
Linus Torvalds 已提交
1533

1534 1535
	validate_creds(cred);

1536
	if (unlikely(IS_PRIVATE(inode)))
1537 1538
		return 0;

1539
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1540 1541 1542 1543
	isec = inode->i_security;

	if (!adp) {
		adp = &ad;
1544
		COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
1545 1546 1547
		ad.u.fs.inode = inode;
	}

1548
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1549 1550 1551 1552 1553
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the dentry to help the auditing code to more easily generate the
   pathname if needed. */
1554
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1555 1556 1557 1558 1559
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1560
	struct common_audit_data ad;
1561

1562
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1563 1564
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1565
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1566 1567 1568 1569 1570 1571 1572 1573 1574 1575
}

/* Check whether a task can use an open file descriptor to
   access an inode in a given way.  Check access to the
   descriptor itself, and then use dentry_has_perm to
   check a particular permission to the file.
   Access to the descriptor is implicitly granted if it
   has the same SID as the process.  If av is zero, then
   access to the file is not checked, e.g. for cases
   where only the descriptor is affected like seek. */
1576 1577 1578
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1579 1580
{
	struct file_security_struct *fsec = file->f_security;
1581
	struct inode *inode = file->f_path.dentry->d_inode;
1582
	struct common_audit_data ad;
1583
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1584 1585
	int rc;

1586
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1587
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1588

1589 1590
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1591 1592 1593 1594
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1595
			goto out;
L
Linus Torvalds 已提交
1596 1597 1598
	}

	/* av is zero if only checking access to the descriptor. */
1599
	rc = 0;
L
Linus Torvalds 已提交
1600
	if (av)
1601
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1602

1603 1604
out:
	return rc;
L
Linus Torvalds 已提交
1605 1606 1607 1608 1609 1610 1611
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1612 1613
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1614 1615
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1616
	u32 sid, newsid;
1617
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1618 1619 1620 1621 1622
	int rc;

	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

1623 1624 1625
	sid = tsec->sid;
	newsid = tsec->create_sid;

1626
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1627
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1628

1629
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1630 1631 1632 1633 1634
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1635
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1636
		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
L
Linus Torvalds 已提交
1637 1638 1639 1640
		if (rc)
			return rc;
	}

1641
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1642 1643 1644 1645 1646 1647 1648 1649
	if (rc)
		return rc;

	return avc_has_perm(newsid, sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE, &ad);
}

1650 1651 1652 1653
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1654
	u32 sid = task_sid(ctx);
1655

1656
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1657 1658
}

1659 1660 1661
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1662 1663 1664 1665 1666 1667 1668 1669

/* Check whether a task can link, unlink, or rmdir a file/directory. */
static int may_link(struct inode *dir,
		    struct dentry *dentry,
		    int kind)

{
	struct inode_security_struct *dsec, *isec;
1670
	struct common_audit_data ad;
1671
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1672 1673 1674 1675 1676 1677
	u32 av;
	int rc;

	dsec = dir->i_security;
	isec = dentry->d_inode->i_security;

1678
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1679
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1680 1681 1682

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1683
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697
	if (rc)
		return rc;

	switch (kind) {
	case MAY_LINK:
		av = FILE__LINK;
		break;
	case MAY_UNLINK:
		av = FILE__UNLINK;
		break;
	case MAY_RMDIR:
		av = DIR__RMDIR;
		break;
	default:
E
Eric Paris 已提交
1698 1699
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1700 1701 1702
		return 0;
	}

1703
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1704 1705 1706 1707 1708 1709 1710 1711 1712
	return rc;
}

static inline int may_rename(struct inode *old_dir,
			     struct dentry *old_dentry,
			     struct inode *new_dir,
			     struct dentry *new_dentry)
{
	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1713
	struct common_audit_data ad;
1714
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1715 1716 1717 1718 1719 1720 1721 1722 1723
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

	old_dsec = old_dir->i_security;
	old_isec = old_dentry->d_inode->i_security;
	old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
	new_dsec = new_dir->i_security;

1724
	COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
1725

1726
	ad.u.fs.path.dentry = old_dentry;
1727
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1728 1729 1730
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1731
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1732 1733 1734 1735
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1736
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1737 1738 1739 1740 1741
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1742
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1743 1744 1745
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1746
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1747 1748 1749 1750 1751
	if (rc)
		return rc;
	if (new_dentry->d_inode) {
		new_isec = new_dentry->d_inode->i_security;
		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1752
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1753 1754 1755 1756 1757 1758 1759 1760 1761 1762
				  new_isec->sclass,
				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
		if (rc)
			return rc;
	}

	return 0;
}

/* Check whether a task can perform a filesystem operation. */
1763
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1764 1765
			       struct super_block *sb,
			       u32 perms,
1766
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1767 1768
{
	struct superblock_security_struct *sbsec;
1769
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1770 1771

	sbsec = sb->s_security;
1772
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1773 1774 1775 1776 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
}

/* Convert a Linux mode and permission mask to an access vector. */
static inline u32 file_mask_to_av(int mode, int mask)
{
	u32 av = 0;

	if ((mode & S_IFMT) != S_IFDIR) {
		if (mask & MAY_EXEC)
			av |= FILE__EXECUTE;
		if (mask & MAY_READ)
			av |= FILE__READ;

		if (mask & MAY_APPEND)
			av |= FILE__APPEND;
		else if (mask & MAY_WRITE)
			av |= FILE__WRITE;

	} else {
		if (mask & MAY_EXEC)
			av |= DIR__SEARCH;
		if (mask & MAY_WRITE)
			av |= DIR__WRITE;
		if (mask & MAY_READ)
			av |= DIR__READ;
	}

	return av;
}

1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825
/* Convert a Linux file to an access vector. */
static inline u32 file_to_av(struct file *file)
{
	u32 av = 0;

	if (file->f_mode & FMODE_READ)
		av |= FILE__READ;
	if (file->f_mode & FMODE_WRITE) {
		if (file->f_flags & O_APPEND)
			av |= FILE__APPEND;
		else
			av |= FILE__WRITE;
	}
	if (!av) {
		/*
		 * Special file opened with flags 3 for ioctl-only use.
		 */
		av = FILE__IOCTL;
	}

	return av;
}

E
Eric Paris 已提交
1826
/*
1827
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1828 1829
 * open permission.
 */
1830
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1831
{
1832
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1833 1834

	if (selinux_policycap_openperm) {
1835
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848
		/*
		 * lnk files and socks do not really have an 'open'
		 */
		if (S_ISREG(mode))
			av |= FILE__OPEN;
		else if (S_ISCHR(mode))
			av |= CHR_FILE__OPEN;
		else if (S_ISBLK(mode))
			av |= BLK_FILE__OPEN;
		else if (S_ISFIFO(mode))
			av |= FIFO_FILE__OPEN;
		else if (S_ISDIR(mode))
			av |= DIR__OPEN;
E
Eric Paris 已提交
1849 1850
		else if (S_ISSOCK(mode))
			av |= SOCK_FILE__OPEN;
E
Eric Paris 已提交
1851
		else
E
Eric Paris 已提交
1852
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1853
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1854 1855 1856 1857
	}
	return av;
}

L
Linus Torvalds 已提交
1858 1859
/* Hook functions begin here. */

1860
static int selinux_ptrace_access_check(struct task_struct *child,
1861
				     unsigned int mode)
L
Linus Torvalds 已提交
1862 1863 1864
{
	int rc;

1865
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1866 1867 1868
	if (rc)
		return rc;

1869
	if (mode == PTRACE_MODE_READ) {
1870 1871 1872
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1873 1874
	}

1875
	return current_has_perm(child, PROCESS__PTRACE);
1876 1877 1878 1879 1880 1881
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
	int rc;

1882
	rc = cap_ptrace_traceme(parent);
1883 1884 1885 1886
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1887 1888 1889
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1890
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1891 1892 1893
{
	int error;

1894
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1895 1896 1897
	if (error)
		return error;

1898
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1899 1900
}

D
David Howells 已提交
1901 1902 1903 1904
static int selinux_capset(struct cred *new, const struct cred *old,
			  const kernel_cap_t *effective,
			  const kernel_cap_t *inheritable,
			  const kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1905 1906 1907
{
	int error;

1908
	error = cap_capset(new, old,
D
David Howells 已提交
1909
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1910 1911 1912
	if (error)
		return error;

D
David Howells 已提交
1913
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1914 1915
}

1916 1917 1918 1919 1920 1921 1922 1923 1924 1925
/*
 * (This comment used to live with the selinux_task_setuid hook,
 * which was removed).
 *
 * Since setuid only affects the current process, and since the SELinux
 * controls are not based on the Linux identity attributes, SELinux does not
 * need to control this operation.  However, SELinux does control the use of
 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
 */

1926 1927
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
			   int cap, int audit)
L
Linus Torvalds 已提交
1928 1929 1930
{
	int rc;

1931
	rc = cap_capable(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1932 1933 1934
	if (rc)
		return rc;

1935
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1936 1937
}

1938 1939 1940 1941 1942 1943
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1944
	buffer = (char *)__get_free_page(GFP_KERNEL);
1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965
	if (!buffer)
		goto out;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (table) {
		const char *name = table->procname;
		size_t namelen = strlen(name);
		buflen -= namelen + 1;
		if (buflen < 0)
			goto out_free;
		end -= namelen;
		memcpy(end, name, namelen);
		*--end = '/';
		path = end;
		table = table->parent;
	}
1966 1967 1968 1969 1970 1971
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1972 1973 1974 1975 1976 1977 1978
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1979 1980 1981 1982
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1983
	u32 tsid, sid;
L
Linus Torvalds 已提交
1984 1985
	int rc;

1986
	sid = current_sid();
L
Linus Torvalds 已提交
1987

1988 1989
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1990 1991 1992 1993 1994 1995 1996
	if (rc) {
		/* Default to the well-defined sysctl SID. */
		tsid = SECINITSID_SYSCTL;
	}

	/* The op values are "defined" in sysctl.c, thereby creating
	 * a bad coupling between this module and sysctl.c */
1997
	if (op == 001) {
1998
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1999 2000 2001 2002 2003 2004 2005 2006
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
2007
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
2008
					     SECCLASS_FILE, av, NULL);
2009
	}
L
Linus Torvalds 已提交
2010 2011 2012 2013 2014 2015

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2016
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2017 2018 2019 2020 2021 2022
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2023 2024 2025 2026 2027
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2028
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2029 2030 2031 2032
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2033
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2034 2035 2036 2037
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2038 2039 2040 2041 2042 2043
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2044 2045 2046
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2047 2048 2049 2050 2051 2052
}

static int selinux_syslog(int type)
{
	int rc;

2053
	rc = cap_syslog(type);
L
Linus Torvalds 已提交
2054 2055 2056 2057
	if (rc)
		return rc;

	switch (type) {
2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074
	case 3:		/* Read last kernel messages */
	case 10:	/* Return size of the log buffer */
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
	case 6:		/* Disable logging to console */
	case 7:		/* Enable logging to console */
	case 8:		/* Set level of messages printed to console */
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
	case 0:		/* Close log */
	case 1:		/* Open log */
	case 2:		/* Read from log */
	case 4:		/* Read/clear last kernel messages */
	case 5:		/* Clear ring buffer */
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086
	}
	return rc;
}

/*
 * Check that a process has enough memory to allocate a new virtual
 * mapping. 0 means there is enough memory for the allocation to
 * succeed and -ENOMEM implies there is not.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
2087
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2088 2089 2090
{
	int rc, cap_sys_admin = 0;

2091 2092
	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2093 2094 2095
	if (rc == 0)
		cap_sys_admin = 1;

2096
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2097 2098 2099 2100
}

/* binprm security operations */

2101
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2102
{
2103 2104
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2105
	struct inode_security_struct *isec;
2106
	struct common_audit_data ad;
2107
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2108 2109
	int rc;

2110
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2111 2112 2113
	if (rc)
		return rc;

2114 2115 2116
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2117 2118
		return 0;

2119 2120
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2121 2122 2123
	isec = inode->i_security;

	/* Default to the current task SID. */
2124 2125
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2126

2127
	/* Reset fs, key, and sock SIDs on execve. */
2128 2129 2130
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2131

2132 2133
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2134
		/* Reset exec SID on execve. */
2135
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2136 2137
	} else {
		/* Check for a default transition on this program. */
2138 2139
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2140 2141 2142 2143
		if (rc)
			return rc;
	}

2144
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2145
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2146

J
Josef Sipek 已提交
2147
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2148
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2149

2150 2151
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2152 2153 2154 2155 2156
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2157
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2158 2159 2160 2161
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2162
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2163 2164 2165 2166
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
					  SECCLASS_PROCESS, PROCESS__SHARE,
					  NULL);
			if (rc)
				return -EPERM;
		}

		/* Make sure that anyone attempting to ptrace over a task that
		 * changes its SID has the appropriate permit */
		if (bprm->unsafe &
		    (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
			struct task_struct *tracer;
			struct task_security_struct *sec;
			u32 ptsid = 0;

			rcu_read_lock();
			tracer = tracehook_tracer_task(current);
			if (likely(tracer != NULL)) {
				sec = __task_cred(tracer)->security;
				ptsid = sec->sid;
			}
			rcu_read_unlock();

			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2200

2201 2202
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2203 2204 2205 2206 2207
	}

	return 0;
}

2208
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2209
{
2210 2211 2212
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2213 2214
	int atsecure = 0;

2215 2216 2217 2218
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2219 2220 2221
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2222
		atsecure = avc_has_perm(osid, sid,
2223 2224
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2225 2226
	}

2227
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2228 2229 2230 2231 2232 2233
}

extern struct vfsmount *selinuxfs_mount;
extern struct dentry *selinux_null;

/* Derived from fs/exec.c:flush_old_files. */
2234 2235
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2236
{
2237
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2238
	struct file *file, *devnull = NULL;
2239
	struct tty_struct *tty;
2240
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2241
	long j = -1;
2242
	int drop_tty = 0;
L
Linus Torvalds 已提交
2243

2244
	tty = get_current_tty();
L
Linus Torvalds 已提交
2245 2246
	if (tty) {
		file_list_lock();
2247 2248 2249
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2250 2251 2252 2253 2254
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
2255 2256
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2257
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2258
					   FILE__READ | FILE__WRITE, NULL)) {
2259
				drop_tty = 1;
L
Linus Torvalds 已提交
2260 2261 2262
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2263
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2264
	}
2265 2266 2267
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2268 2269 2270

	/* Revalidate access to inherited open files. */

2271
	COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2272 2273 2274 2275 2276 2277 2278 2279

	spin_lock(&files->file_lock);
	for (;;) {
		unsigned long set, i;
		int fd;

		j++;
		i = j * __NFDBITS;
2280
		fdt = files_fdtable(files);
2281
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2282
			break;
2283
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2284 2285 2286
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2287
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2288 2289 2290 2291
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2292
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2304
						get_file(devnull);
L
Linus Torvalds 已提交
2305
					} else {
2306 2307 2308 2309
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2310 2311
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2328 2329 2330 2331
/*
 * Prepare a process for imminent new credential changes due to exec
 */
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2332
{
2333 2334 2335
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2336

2337 2338 2339
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2340

2341 2342
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2343

2344 2345
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2346

2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363
	/* Check whether the new SID can inherit resource limits from the old
	 * SID.  If not, reset all soft limits to the lower of the current
	 * task's hard limit and the init task's soft limit.
	 *
	 * Note that the setting of hard limits (even to lower them) can be
	 * controlled by the setrlimit check.  The inclusion of the init task's
	 * soft limit into the computation is to avoid resetting soft limits
	 * higher than the default soft limit for cases where the default is
	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
	 */
	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
		for (i = 0; i < RLIM_NLIMITS; i++) {
			rlim = current->signal->rlim + i;
			initrlim = init_task.signal->rlim + i;
			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
L
Linus Torvalds 已提交
2364
		}
2365
		update_rlimit_cpu(rlim->rlim_cur);
L
Linus Torvalds 已提交
2366 2367 2368 2369
	}
}

/*
2370 2371
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2372
 */
2373
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2374
{
2375
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2376
	struct itimerval itimer;
2377
	u32 osid, sid;
L
Linus Torvalds 已提交
2378 2379
	int rc, i;

2380 2381 2382 2383
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2384 2385
		return;

2386 2387 2388 2389 2390 2391 2392 2393
	/* Check whether the new SID can inherit signal state from the old SID.
	 * If not, clear itimers to avoid subsequent signal generation and
	 * flush and unblock signals.
	 *
	 * This must occur _after_ the task SID has been updated so that any
	 * kill done after the flush will be checked against the new SID.
	 */
	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
L
Linus Torvalds 已提交
2394 2395 2396 2397 2398
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2399 2400 2401 2402 2403
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2404 2405 2406
		spin_unlock_irq(&current->sighand->siglock);
	}

2407 2408
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2409 2410 2411
	read_lock(&tasklist_lock);
	wake_up_interruptible(&current->real_parent->signal->wait_chldexit);
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435
}

/* superblock security operations */

static int selinux_sb_alloc_security(struct super_block *sb)
{
	return superblock_alloc_security(sb);
}

static void selinux_sb_free_security(struct super_block *sb)
{
	superblock_free_security(sb);
}

static inline int match_prefix(char *prefix, int plen, char *option, int olen)
{
	if (plen > olen)
		return 0;

	return !memcmp(prefix, option, plen);
}

static inline int selinux_option(char *option, int len)
{
2436 2437 2438
	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2439 2440
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
L
Linus Torvalds 已提交
2441 2442 2443 2444 2445 2446 2447
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2448
	} else
L
Linus Torvalds 已提交
2449 2450 2451 2452 2453
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2454 2455
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2456 2457 2458 2459 2460 2461
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2462
	} else
2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474
		*first = 0;

	while (current_size < len) {
		if (*from != '"') {
			**to = *from;
			*to += 1;
		}
		from += 1;
		current_size += 1;
	}
}

2475
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2476 2477 2478 2479
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2480
	int open_quote = 0;
L
Linus Torvalds 已提交
2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495

	in_curr = orig;
	sec_curr = copy;

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

	nosec_save = nosec;
	fnosec = fsec = 1;
	in_save = in_end = orig;

	do {
2496 2497 2498 2499
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2500 2501 2502
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2503
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2504 2505 2506 2507 2508 2509 2510
			else
				take_option(&nosec, in_curr, &fnosec, len);

			in_curr = in_end + 1;
		}
	} while (*in_end++);

2511
	strcpy(in_save, nosec_save);
2512
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2513 2514 2515 2516
out:
	return rc;
}

2517
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2518
{
2519
	const struct cred *cred = current_cred();
2520
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2521 2522 2523 2524 2525 2526
	int rc;

	rc = superblock_doinit(sb, data);
	if (rc)
		return rc;

2527 2528 2529 2530
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2531
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2532
	ad.u.fs.path.dentry = sb->s_root;
2533
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2534 2535
}

2536
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2537
{
2538
	const struct cred *cred = current_cred();
2539
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2540

2541
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2542
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2543
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2544 2545
}

2546
static int selinux_mount(char *dev_name,
2547
			 struct path *path,
2548 2549 2550
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2551
{
2552
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2553 2554

	if (flags & MS_REMOUNT)
2555
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2556
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2557
	else
2558
		return dentry_has_perm(cred, path->mnt, path->dentry,
2559
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2560 2561 2562 2563
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2564
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2565

2566
	return superblock_has_perm(cred, mnt->mnt_sb,
2567
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581
}

/* inode security operations */

static int selinux_inode_alloc_security(struct inode *inode)
{
	return inode_alloc_security(inode);
}

static void selinux_inode_free_security(struct inode *inode)
{
	inode_free_security(inode);
}

2582 2583 2584 2585
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2586 2587
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2588 2589
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2590
	u32 sid, newsid, clen;
2591
	int rc;
2592
	char *namep = NULL, *context;
2593 2594 2595 2596

	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

2597 2598 2599
	sid = tsec->sid;
	newsid = tsec->create_sid;

2600
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2601
		rc = security_transition_sid(sid, dsec->sid,
2602 2603 2604 2605 2606 2607
					     inode_mode_to_security_class(inode->i_mode),
					     &newsid);
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2608
			       __func__,
2609 2610 2611 2612 2613
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2614
	/* Possibly defer initialization to selinux_complete_init. */
2615
	if (sbsec->flags & SE_SBINITIALIZED) {
2616 2617 2618 2619 2620
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2621

2622
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2623 2624
		return -EOPNOTSUPP;

2625
	if (name) {
2626
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2627 2628 2629 2630
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2631

2632
	if (value && len) {
2633
		rc = security_sid_to_context_force(newsid, &context, &clen);
2634 2635 2636 2637 2638 2639
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2640 2641 2642 2643 2644
	}

	return 0;
}

L
Linus Torvalds 已提交
2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
{
	return may_link(dir, old_dentry, MAY_LINK);
}

static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
{
	return may_link(dir, dentry, MAY_UNLINK);
}

static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
{
	return may_create(dir, dentry, SECCLASS_LNK_FILE);
}

static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_DIR);
}

static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
{
	return may_link(dir, dentry, MAY_RMDIR);
}

static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2681
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2682 2683 2684 2685 2686 2687
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2688 2689 2690
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2691 2692 2693 2694
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2695
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2696

2697
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2698 2699
}

2700
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2701
{
2702
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2703 2704 2705 2706 2707 2708

	if (!mask) {
		/* No permission to check.  Existence test. */
		return 0;
	}

2709
	return inode_has_perm(cred, inode,
2710
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2711 2712 2713 2714
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2715
	const struct cred *cred = current_cred();
2716
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2717

2718 2719 2720 2721 2722 2723 2724
	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
	if (ia_valid & ATTR_FORCE) {
		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
			      ATTR_FORCE);
		if (!ia_valid)
			return 0;
	}
L
Linus Torvalds 已提交
2725

2726 2727
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2728
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2729

2730
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2731 2732 2733 2734
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2735 2736 2737
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2738 2739
}

2740
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2741
{
2742 2743
	const struct cred *cred = current_cred();

2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757
	if (!strncmp(name, XATTR_SECURITY_PREFIX,
		     sizeof XATTR_SECURITY_PREFIX - 1)) {
		if (!strcmp(name, XATTR_NAME_CAPS)) {
			if (!capable(CAP_SETFCAP))
				return -EPERM;
		} else if (!capable(CAP_SYS_ADMIN)) {
			/* A different attribute in the security namespace.
			   Restrict to administrator. */
			return -EPERM;
		}
	}

	/* Not an attribute we recognize, so just check the
	   ordinary setattr permission. */
2758
	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2759 2760
}

2761 2762
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
				  const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2763 2764 2765 2766
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2767
	struct common_audit_data ad;
2768
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2769 2770
	int rc = 0;

2771 2772
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2773 2774

	sbsec = inode->i_sb->s_security;
2775
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2776 2777
		return -EOPNOTSUPP;

2778
	if (!is_owner_or_cap(inode))
L
Linus Torvalds 已提交
2779 2780
		return -EPERM;

2781
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2782
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2783

2784
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2785 2786 2787 2788 2789
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2790 2791 2792 2793 2794
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2795 2796 2797
	if (rc)
		return rc;

2798
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2799 2800 2801 2802
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2803
	rc = security_validate_transition(isec->sid, newsid, sid,
2804
					  isec->sclass);
L
Linus Torvalds 已提交
2805 2806 2807 2808 2809 2810 2811 2812 2813 2814
	if (rc)
		return rc;

	return avc_has_perm(newsid,
			    sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE,
			    &ad);
}

2815
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2816
					const void *value, size_t size,
2817
					int flags)
L
Linus Torvalds 已提交
2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_NAME_SELINUX)) {
		/* Not an attribute we recognize, so nothing to do. */
		return;
	}

2829
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2830
	if (rc) {
2831 2832 2833
		printk(KERN_ERR "SELinux:  unable to map context to SID"
		       "for (%s, %lu), rc=%d\n",
		       inode->i_sb->s_id, inode->i_ino, -rc);
L
Linus Torvalds 已提交
2834 2835 2836 2837 2838 2839 2840
		return;
	}

	isec->sid = newsid;
	return;
}

2841
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2842
{
2843 2844 2845
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2846 2847
}

2848
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2849
{
2850 2851 2852
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2853 2854
}

2855
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2856
{
2857 2858
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2859 2860 2861 2862 2863 2864

	/* No one is allowed to remove a SELinux security label.
	   You can change the label, but all data must be labeled. */
	return -EACCES;
}

2865
/*
2866
 * Copy the inode security context value to the user.
2867 2868 2869
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2870
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2871
{
2872 2873 2874
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2875
	struct inode_security_struct *isec = inode->i_security;
2876

2877 2878
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2879

2880 2881 2882 2883 2884 2885 2886 2887 2888
	/*
	 * If the caller has CAP_MAC_ADMIN, then get the raw context
	 * value even if it is not defined by current policy; otherwise,
	 * use the in-core value under current policy.
	 * Use the non-auditing forms of the permission checks since
	 * getxattr may be called by unprivileged processes commonly
	 * and lack of permission just means that we fall back to the
	 * in-core context value, not a denial.
	 */
2889 2890
	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
				SECURITY_CAP_NOAUDIT);
2891 2892 2893 2894 2895
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2896 2897 2898 2899 2900 2901 2902 2903 2904 2905
	if (error)
		return error;
	error = size;
	if (alloc) {
		*buffer = context;
		goto out_nofree;
	}
	kfree(context);
out_nofree:
	return error;
L
Linus Torvalds 已提交
2906 2907 2908
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2909
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
{
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;

	if (!value || !size)
		return -EACCES;

2921
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
	if (rc)
		return rc;

	isec->sid = newsid;
	return 0;
}

static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
{
	const int len = sizeof(XATTR_NAME_SELINUX);
	if (buffer && len <= buffer_size)
		memcpy(buffer, XATTR_NAME_SELINUX, len);
	return len;
}

2937 2938 2939 2940 2941 2942
static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
{
	struct inode_security_struct *isec = inode->i_security;
	*secid = isec->sid;
}

L
Linus Torvalds 已提交
2943 2944
/* file security operations */

2945
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2946
{
2947
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2948
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2949 2950 2951 2952 2953

	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
		mask |= MAY_APPEND;

2954 2955
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2956 2957
}

2958 2959
static int selinux_file_permission(struct file *file, int mask)
{
2960 2961 2962 2963 2964
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2965
	if (!mask)
2966 2967 2968
		/* No permission to check.  Existence test. */
		return 0;

2969 2970 2971 2972 2973
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2974 2975 2976
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989
static int selinux_file_alloc_security(struct file *file)
{
	return file_alloc_security(file);
}

static void selinux_file_free_security(struct file *file)
{
	file_free_security(file);
}

static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
2990
	const struct cred *cred = current_cred();
2991
	u32 av = 0;
L
Linus Torvalds 已提交
2992

2993 2994 2995 2996 2997 2998
	if (_IOC_DIR(cmd) & _IOC_WRITE)
		av |= FILE__WRITE;
	if (_IOC_DIR(cmd) & _IOC_READ)
		av |= FILE__READ;
	if (!av)
		av = FILE__IOCTL;
L
Linus Torvalds 已提交
2999

3000
	return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3001 3002 3003 3004
}

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3005
	const struct cred *cred = current_cred();
D
David Howells 已提交
3006
	int rc = 0;
3007

L
Linus Torvalds 已提交
3008 3009 3010 3011 3012 3013 3014
#ifndef CONFIG_PPC32
	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
D
David Howells 已提交
3015
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3016
		if (rc)
D
David Howells 已提交
3017
			goto error;
L
Linus Torvalds 已提交
3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031
	}
#endif

	if (file) {
		/* read access is always possible with a mapping */
		u32 av = FILE__READ;

		/* write access only matters if the mapping is shared */
		if (shared && (prot & PROT_WRITE))
			av |= FILE__WRITE;

		if (prot & PROT_EXEC)
			av |= FILE__EXECUTE;

3032
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3033
	}
D
David Howells 已提交
3034 3035 3036

error:
	return rc;
L
Linus Torvalds 已提交
3037 3038 3039
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3040 3041
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3042
{
3043
	int rc = 0;
3044
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3045

3046 3047 3048 3049 3050 3051
	/*
	 * notice that we are intentionally putting the SELinux check before
	 * the secondary cap_file_mmap check.  This is such a likely attempt
	 * at bad behaviour/exploit that we always want to get the AVC, even
	 * if DAC would have also denied the operation.
	 */
3052
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3053 3054
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3055 3056 3057 3058 3059 3060
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3061
	if (rc || addr_only)
L
Linus Torvalds 已提交
3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

	return file_map_prot_check(file, prot,
				   (flags & MAP_TYPE) == MAP_SHARED);
}

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3075
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3076 3077 3078 3079 3080

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3081
	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3082
		int rc = 0;
3083 3084
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3085
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3086 3087 3088
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3089
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3090 3091 3092 3093 3094 3095 3096 3097
		} else if (vma->vm_file && vma->anon_vma) {
			/*
			 * We are making executable a file mapping that has
			 * had some COW done. Since pages might have been
			 * written, check ability to execute the possibly
			 * modified content.  This typically should only
			 * occur for text relocations.
			 */
D
David Howells 已提交
3098
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3099
		}
3100 3101 3102
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3103 3104 3105 3106 3107 3108 3109
#endif

	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
}

static int selinux_file_lock(struct file *file, unsigned int cmd)
{
3110 3111 3112
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3113 3114 3115 3116 3117
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3118
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3119 3120 3121
	int err = 0;

	switch (cmd) {
3122 3123 3124 3125 3126
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3127

3128
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3129
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3130
			break;
3131 3132 3133 3134 3135 3136 3137 3138
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3139
		err = file_has_perm(cred, file, 0);
3140 3141 3142 3143
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3144
#if BITS_PER_LONG == 32
3145 3146 3147
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3148
#endif
3149 3150
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3151
			break;
3152
		}
3153
		err = file_has_perm(cred, file, FILE__LOCK);
3154
		break;
L
Linus Torvalds 已提交
3155 3156 3157 3158 3159 3160 3161 3162 3163 3164
	}

	return err;
}

static int selinux_file_set_fowner(struct file *file)
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3165
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3166 3167 3168 3169 3170 3171 3172

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3173
	struct file *file;
3174
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3175 3176 3177 3178
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3179
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3180 3181 3182 3183 3184 3185 3186 3187

	fsec = file->f_security;

	if (!signum)
		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
	else
		perm = signal_to_av(signum);

3188
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3189 3190 3191 3192 3193
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3194 3195 3196
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3197 3198
}

3199
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3200 3201 3202 3203
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3204

3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3225
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3226 3227
}

L
Linus Torvalds 已提交
3228 3229 3230 3231
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3232
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3233 3234
}

D
David Howells 已提交
3235 3236 3237 3238
/*
 * detach and free the LSM part of a set of credentials
 */
static void selinux_cred_free(struct cred *cred)
L
Linus Torvalds 已提交
3239
{
D
David Howells 已提交
3240
	struct task_security_struct *tsec = cred->security;
3241 3242 3243

	BUG_ON((unsigned long) cred->security < PAGE_SIZE);
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3244 3245
	kfree(tsec);
}
L
Linus Torvalds 已提交
3246

D
David Howells 已提交
3247 3248 3249 3250 3251 3252 3253 3254
/*
 * prepare a new set of credentials for modification
 */
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
				gfp_t gfp)
{
	const struct task_security_struct *old_tsec;
	struct task_security_struct *tsec;
L
Linus Torvalds 已提交
3255

D
David Howells 已提交
3256
	old_tsec = old->security;
L
Linus Torvalds 已提交
3257

D
David Howells 已提交
3258 3259 3260
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3261

D
David Howells 已提交
3262
	new->security = tsec;
L
Linus Torvalds 已提交
3263 3264 3265
	return 0;
}

3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309
/*
 * set the security data for a kernel service
 * - all the creation contexts are set to unlabelled
 */
static int selinux_kernel_act_as(struct cred *new, u32 secid)
{
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, secid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__USE_AS_OVERRIDE,
			   NULL);
	if (ret == 0) {
		tsec->sid = secid;
		tsec->create_sid = 0;
		tsec->keycreate_sid = 0;
		tsec->sockcreate_sid = 0;
	}
	return ret;
}

/*
 * set the file creation context in a security record to the same as the
 * objective context of the specified inode
 */
static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, isec->sid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__CREATE_FILES_AS,
			   NULL);

	if (ret == 0)
		tsec->create_sid = isec->sid;
	return 0;
}

3310 3311 3312 3313 3314
static int selinux_kernel_module_request(void)
{
	return task_has_system(current, SYSTEM__MODULE_REQUEST);
}

L
Linus Torvalds 已提交
3315 3316
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3317
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3318 3319 3320 3321
}

static int selinux_task_getpgid(struct task_struct *p)
{
3322
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3323 3324 3325 3326
}

static int selinux_task_getsid(struct task_struct *p)
{
3327
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3328 3329
}

3330 3331
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3332
	*secid = task_sid(p);
3333 3334
}

L
Linus Torvalds 已提交
3335 3336 3337 3338
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3339
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3340 3341 3342
	if (rc)
		return rc;

3343
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3344 3345
}

3346 3347
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3348 3349
	int rc;

3350
	rc = cap_task_setioprio(p, ioprio);
3351 3352 3353
	if (rc)
		return rc;

3354
	return current_has_perm(p, PROCESS__SETSCHED);
3355 3356
}

3357 3358
static int selinux_task_getioprio(struct task_struct *p)
{
3359
	return current_has_perm(p, PROCESS__GETSCHED);
3360 3361
}

L
Linus Torvalds 已提交
3362 3363 3364 3365 3366 3367 3368
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
	struct rlimit *old_rlim = current->signal->rlim + resource;

	/* Control the ability to change the hard limit (whether
	   lowering or raising it), so that the hard limit can
	   later be used as a safe reset point for the soft limit
D
David Howells 已提交
3369
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3370
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3371
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3372 3373 3374 3375 3376 3377

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3378 3379
	int rc;

3380
	rc = cap_task_setscheduler(p, policy, lp);
3381 3382 3383
	if (rc)
		return rc;

3384
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3385 3386 3387 3388
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3389
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3390 3391
}

3392 3393
static int selinux_task_movememory(struct task_struct *p)
{
3394
	return current_has_perm(p, PROCESS__SETSCHED);
3395 3396
}

3397 3398
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3399 3400 3401 3402 3403 3404 3405 3406
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3407
	if (secid)
3408 3409
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3410
	else
3411
		rc = current_has_perm(p, perm);
3412
	return rc;
L
Linus Torvalds 已提交
3413 3414 3415 3416
}

static int selinux_task_wait(struct task_struct *p)
{
3417
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3418 3419 3420 3421 3422 3423
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3424
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3425

3426
	isec->sid = sid;
L
Linus Torvalds 已提交
3427 3428 3429 3430
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3431
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3432
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3433 3434 3435 3436
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3437
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

	ihlen = ih->ihl * 4;
	if (ihlen < sizeof(_iph))
		goto out;

	ad->u.net.v4info.saddr = ih->saddr;
	ad->u.net.v4info.daddr = ih->daddr;
	ret = 0;

3450 3451 3452
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3453
	switch (ih->protocol) {
3454 3455
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3456

3457 3458
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3459 3460 3461 3462 3463 3464 3465 3466 3467

		offset += ihlen;
		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3468 3469 3470 3471 3472 3473 3474 3475
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

L
Linus Torvalds 已提交
3476
		offset += ihlen;
3477
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3478
		if (uh == NULL)
3479
			break;
L
Linus Torvalds 已提交
3480

3481 3482 3483 3484
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3485

J
James Morris 已提交
3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		offset += ihlen;
		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3500
	}
J
James Morris 已提交
3501

3502 3503 3504
	default:
		break;
	}
L
Linus Torvalds 已提交
3505 3506 3507 3508 3509 3510 3511
out:
	return ret;
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

/* Returns error only if unable to parse addresses */
3512
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3513
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3514 3515 3516 3517 3518
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3519
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3520 3521 3522 3523 3524 3525 3526 3527 3528 3529
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

	ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
	ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3530
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3531 3532 3533
	if (offset < 0)
		goto out;

3534 3535 3536
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3537 3538
	switch (nexthdr) {
	case IPPROTO_TCP: {
3539
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561

		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
		if (uh == NULL)
			break;

		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}

J
James Morris 已提交
3562 3563 3564 3565 3566 3567 3568 3569 3570 3571
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3572
	}
J
James Morris 已提交
3573

L
Linus Torvalds 已提交
3574 3575 3576 3577 3578 3579 3580 3581 3582 3583
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3584
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3585
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3586
{
3587 3588
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3589 3590 3591

	switch (ad->u.net.family) {
	case PF_INET:
3592
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3593 3594 3595 3596 3597
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3598 3599 3600

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3601
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3602 3603 3604 3605 3606
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3607 3608
#endif	/* IPV6 */
	default:
3609 3610
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3611 3612
	}

3613 3614 3615 3616
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3617
	return ret;
3618 3619 3620 3621 3622

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3623 3624
}

3625
/**
3626
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3627
 * @skb: the packet
3628
 * @family: protocol family
3629
 * @sid: the packet's peer label SID
3630 3631
 *
 * Description:
3632 3633 3634 3635 3636 3637
 * Check the various different forms of network peer labeling and determine
 * the peer label/SID for the packet; most of the magic actually occurs in
 * the security server function security_net_peersid_cmp().  The function
 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
 * or -EACCES if @sid is invalid due to inconsistencies with the different
 * peer labels.
3638 3639
 *
 */
3640
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3641
{
3642
	int err;
3643 3644
	u32 xfrm_sid;
	u32 nlbl_sid;
3645
	u32 nlbl_type;
3646 3647

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3648
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3649

3650 3651 3652 3653 3654
	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
		       " unable to determine packet's peer label\n");
3655
		return -EACCES;
3656
	}
3657 3658

	return 0;
3659 3660
}

L
Linus Torvalds 已提交
3661 3662 3663 3664 3665
/* socket security operations */
static int socket_has_perm(struct task_struct *task, struct socket *sock,
			   u32 perms)
{
	struct inode_security_struct *isec;
3666
	struct common_audit_data ad;
3667
	u32 sid;
L
Linus Torvalds 已提交
3668 3669 3670 3671 3672 3673
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3674
	sid = task_sid(task);
L
Linus Torvalds 已提交
3675

3676
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3677
	ad.u.net.sk = sock->sk;
3678
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3679 3680 3681 3682 3683 3684 3685 3686

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3687 3688 3689 3690
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, newsid;
	u16 secclass;
L
Linus Torvalds 已提交
3691 3692 3693 3694 3695
	int err = 0;

	if (kern)
		goto out;

3696 3697 3698 3699 3700
	sid = tsec->sid;
	newsid = tsec->sockcreate_sid ?: sid;

	secclass = socket_type_to_security_class(family, type, protocol);
	err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3701 3702 3703 3704 3705

out:
	return err;
}

V
Venkat Yekkirala 已提交
3706 3707
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3708
{
3709 3710
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3711
	struct inode_security_struct *isec;
3712
	struct sk_security_struct *sksec;
3713 3714 3715 3716 3717
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3718 3719 3720

	isec = SOCK_INODE(sock)->i_security;

3721 3722 3723 3724 3725 3726 3727
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3728 3729 3730
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3731 3732 3733
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3734
		sksec->sclass = isec->sclass;
3735
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3736 3737
	}

V
Venkat Yekkirala 已提交
3738
	return err;
L
Linus Torvalds 已提交
3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755
}

/* Range of port numbers used to automatically bind.
   Need to determine whether we should perform a name_bind
   permission check between the socket and the port number. */

static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
{
	u16 family;
	int err;

	err = socket_has_perm(current, sock, SOCKET__BIND);
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3756 3757
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3758 3759 3760 3761 3762
	 */
	family = sock->sk->sk_family;
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
		struct inode_security_struct *isec;
3763
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3764 3765 3766 3767
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
		struct sock *sk = sock->sk;
3768
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781

		isec = SOCK_INODE(sock)->i_security;

		if (family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
			snum = ntohs(addr4->sin_port);
			addrp = (char *)&addr4->sin_addr.s_addr;
		} else {
			addr6 = (struct sockaddr_in6 *)address;
			snum = ntohs(addr6->sin6_port);
			addrp = (char *)&addr6->sin6_addr.s6_addr;
		}

3782 3783 3784 3785 3786 3787
		if (snum) {
			int low, high;

			inet_get_local_port_range(&low, &high);

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3788 3789
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3790 3791
				if (err)
					goto out;
3792
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3793 3794 3795 3796 3797 3798 3799 3800
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
				err = avc_has_perm(isec->sid, sid,
						   isec->sclass,
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3801
		}
3802 3803

		switch (isec->sclass) {
3804
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3805 3806
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3807

3808
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3809 3810
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3811 3812 3813 3814 3815

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3816 3817 3818 3819
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3820

3821
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3822 3823
		if (err)
			goto out;
3824

3825
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3826 3827 3828 3829 3830 3831 3832 3833 3834
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

		if (family == PF_INET)
			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
		else
			ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);

		err = avc_has_perm(isec->sid, sid,
3835
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3836 3837 3838 3839 3840 3841 3842 3843 3844
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3845
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3846 3847 3848 3849 3850 3851 3852 3853
	struct inode_security_struct *isec;
	int err;

	err = socket_has_perm(current, sock, SOCKET__CONNECT);
	if (err)
		return err;

	/*
J
James Morris 已提交
3854
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3855 3856
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3857 3858
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
3859
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3860 3861 3862
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3863
		u32 sid, perm;
L
Linus Torvalds 已提交
3864 3865 3866

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3867
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3868 3869 3870 3871
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3872
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3873 3874 3875 3876
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3877
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3878 3879 3880
		if (err)
			goto out;

J
James Morris 已提交
3881 3882 3883
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3884
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3885 3886
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3887
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3888 3889 3890 3891
		if (err)
			goto out;
	}

3892 3893
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
	return socket_has_perm(current, sock, SOCKET__LISTEN);
}

static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
{
	int err;
	struct inode_security_struct *isec;
	struct inode_security_struct *newisec;

	err = socket_has_perm(current, sock, SOCKET__ACCEPT);
	if (err)
		return err;

	newisec = SOCK_INODE(newsock)->i_security;

	isec = SOCK_INODE(sock)->i_security;
	newisec->sclass = isec->sclass;
	newisec->sid = isec->sid;
	newisec->initialized = 1;

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3924
				  int size)
L
Linus Torvalds 已提交
3925
{
3926
	return socket_has_perm(current, sock, SOCKET__WRITE);
L
Linus Torvalds 已提交
3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
	return socket_has_perm(current, sock, SOCKET__READ);
}

static int selinux_socket_getsockname(struct socket *sock)
{
	return socket_has_perm(current, sock, SOCKET__GETATTR);
}

static int selinux_socket_getpeername(struct socket *sock)
{
	return socket_has_perm(current, sock, SOCKET__GETATTR);
}

3945
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3946
{
3947 3948 3949 3950 3951 3952 3953
	int err;

	err = socket_has_perm(current, sock, SOCKET__SETOPT);
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
	return socket_has_perm(current, sock, SOCKET__GETOPT);
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
	return socket_has_perm(current, sock, SOCKET__SHUTDOWN);
}

static int selinux_socket_unix_stream_connect(struct socket *sock,
					      struct socket *other,
					      struct sock *newsk)
{
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
3974
	struct common_audit_data ad;
L
Linus Torvalds 已提交
3975 3976 3977 3978 3979
	int err;

	isec = SOCK_INODE(sock)->i_security;
	other_isec = SOCK_INODE(other)->i_security;

3980
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991
	ad.u.net.sk = other->sk;

	err = avc_has_perm(isec->sid, other_isec->sid,
			   isec->sclass,
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* connecting socket */
	ssec = sock->sk->sk_security;
	ssec->peer_sid = other_isec->sid;
3992

L
Linus Torvalds 已提交
3993 3994 3995
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
3996 3997 3998
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
3999 4000 4001 4002 4003 4004 4005
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
4006
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4007 4008 4009 4010 4011
	int err;

	isec = SOCK_INODE(sock)->i_security;
	other_isec = SOCK_INODE(other)->i_security;

4012
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4013 4014 4015 4016 4017 4018 4019 4020 4021 4022
	ad.u.net.sk = other->sk;

	err = avc_has_perm(isec->sid, other_isec->sid,
			   isec->sclass, SOCKET__SENDTO, &ad);
	if (err)
		return err;

	return 0;
}

4023 4024
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4025
				    struct common_audit_data *ad)
4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045
{
	int err;
	u32 if_sid;
	u32 node_sid;

	err = sel_netif_sid(ifindex, &if_sid);
	if (err)
		return err;
	err = avc_has_perm(peer_sid, if_sid,
			   SECCLASS_NETIF, NETIF__INGRESS, ad);
	if (err)
		return err;

	err = sel_netnode_sid(addrp, family, &node_sid);
	if (err)
		return err;
	return avc_has_perm(peer_sid, node_sid,
			    SECCLASS_NODE, NODE__RECVFROM, ad);
}

4046
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4047
				       u16 family)
4048
{
4049
	int err = 0;
4050 4051 4052
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4053
	struct common_audit_data ad;
4054 4055
	char *addrp;

4056
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4057 4058 4059 4060 4061
	ad.u.net.netif = skb->iif;
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4062

4063
	if (selinux_secmark_enabled()) {
4064
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4065
				   PACKET__RECV, &ad);
4066 4067 4068
		if (err)
			return err;
	}
4069 4070 4071 4072 4073 4074

	if (selinux_policycap_netpeer) {
		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
		if (err)
			return err;
		err = avc_has_perm(sk_sid, peer_sid,
4075
				   SECCLASS_PEER, PEER__RECV, &ad);
4076 4077
		if (err)
			selinux_netlbl_err(skb, err, 0);
4078
	} else {
4079
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4080 4081
		if (err)
			return err;
4082
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4083
	}
4084

4085 4086 4087 4088 4089
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4090
	int err;
4091
	struct sk_security_struct *sksec = sk->sk_security;
4092 4093
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4094
	struct common_audit_data ad;
4095
	char *addrp;
4096 4097
	u8 secmark_active;
	u8 peerlbl_active;
4098 4099

	if (family != PF_INET && family != PF_INET6)
4100
		return 0;
4101 4102

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4103
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4104 4105
		family = PF_INET;

4106 4107 4108 4109
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_sock_rcv_skb_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
4110
	if (!selinux_policycap_netpeer)
4111 4112 4113 4114 4115 4116 4117
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return 0;

4118
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4119
	ad.u.net.netif = skb->iif;
4120
	ad.u.net.family = family;
4121
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4122
	if (err)
4123
		return err;
4124

4125
	if (peerlbl_active) {
4126 4127 4128
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4129 4130 4131 4132
		if (err)
			return err;
		err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
					       peer_sid, &ad);
4133 4134
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4135
			return err;
4136
		}
4137 4138
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4139 4140
		if (err)
			selinux_netlbl_err(skb, err, 0);
4141 4142
	}

4143
	if (secmark_active) {
4144 4145 4146 4147 4148 4149
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4150
	return err;
L
Linus Torvalds 已提交
4151 4152
}

C
Catherine Zhang 已提交
4153 4154
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4155 4156 4157 4158 4159 4160
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4161
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4162 4163

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4164

4165 4166
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4167 4168 4169
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4170
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4171 4172 4173 4174
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4175 4176
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192
	if (err)
		goto out;

	if (scontext_len > len) {
		err = -ERANGE;
		goto out_len;
	}

	if (copy_to_user(optval, scontext, scontext_len))
		err = -EFAULT;

out_len:
	if (put_user(scontext_len, optlen))
		err = -EFAULT;

	kfree(scontext);
4193
out:
L
Linus Torvalds 已提交
4194 4195 4196
	return err;
}

4197
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4198
{
4199
	u32 peer_secid = SECSID_NULL;
4200
	u16 family;
C
Catherine Zhang 已提交
4201

4202 4203 4204 4205 4206
	if (skb && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;
	else if (skb && skb->protocol == htons(ETH_P_IPV6))
		family = PF_INET6;
	else if (sock)
4207 4208 4209 4210 4211
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4212
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4213
	else if (skb)
4214
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4215

4216
out:
4217
	*secid = peer_secid;
4218 4219 4220
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4221 4222
}

A
Al Viro 已提交
4223
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4224 4225 4226 4227 4228 4229 4230 4231 4232
{
	return sk_alloc_security(sk, family, priority);
}

static void selinux_sk_free_security(struct sock *sk)
{
	sk_free_security(sk);
}

4233
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4234
{
4235 4236
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4237

4238 4239
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4240
	newssec->sclass = ssec->sclass;
4241

4242
	selinux_netlbl_sk_security_reset(newssec);
4243 4244
}

V
Venkat Yekkirala 已提交
4245
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4246
{
4247
	if (!sk)
V
Venkat Yekkirala 已提交
4248
		*secid = SECINITSID_ANY_SOCKET;
4249 4250
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4251

V
Venkat Yekkirala 已提交
4252
		*secid = sksec->sid;
4253
	}
4254 4255
}

4256
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4257 4258 4259 4260
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4261 4262 4263
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4264
	sksec->sclass = isec->sclass;
4265 4266
}

4267 4268
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4269 4270 4271
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4272
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4273
	u32 newsid;
4274 4275
	u32 peersid;

4276 4277 4278 4279 4280
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4281 4282
	if (err)
		return err;
4283 4284
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4285
		req->peer_secid = SECSID_NULL;
4286 4287 4288 4289 4290 4291
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4292 4293
	}

4294
	return selinux_netlbl_inet_conn_request(req, family);
4295 4296
}

4297 4298
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4299 4300 4301 4302
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4303
	newsksec->peer_sid = req->peer_secid;
4304 4305 4306 4307
	/* NOTE: Ideally, we should also get the isec->sid for the
	   new socket in sync, but we don't have the isec available yet.
	   So we will wait until sock_graft to do it, by which
	   time it will have been created and available. */
4308

P
Paul Moore 已提交
4309 4310
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4311
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4312 4313
}

4314
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4315
{
4316
	u16 family = sk->sk_family;
4317 4318
	struct sk_security_struct *sksec = sk->sk_security;

4319 4320 4321 4322 4323
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4324 4325
}

4326 4327
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4328 4329 4330 4331
{
	fl->secid = req->secid;
}

4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

	/* we aren't taking into account the "sockcreate" SID since the socket
	 * that is being created here is not a socket in the traditional sense,
	 * instead it is a private sock, accessible only to the kernel, and
	 * representing a wide range of network traffic spanning multiple
	 * connections unlike traditional sockets - check the TUN driver to
	 * get a better understanding of why this socket is special */

	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
			    NULL);
}

static void selinux_tun_dev_post_create(struct sock *sk)
{
	struct sk_security_struct *sksec = sk->sk_security;

	/* we don't currently perform any NetLabel based labeling here and it
	 * isn't clear that we would want to do so anyway; while we could apply
	 * labeling without the support of the TUN user the resulting labeled
	 * traffic from the other end of the connection would almost certainly
	 * cause confusion to the TUN user that had no idea network labeling
	 * protocols were being used */

	/* see the comments in selinux_tun_dev_create() about why we don't use
	 * the sockcreate SID here */

	sksec->sid = current_sid();
	sksec->sclass = SECCLASS_TUN_SOCKET;
}

static int selinux_tun_dev_attach(struct sock *sk)
{
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sid = current_sid();
	int err;

	err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
			   TUN_SOCKET__RELABELFROM, NULL);
	if (err)
		return err;
	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
			   TUN_SOCKET__RELABELTO, NULL);
	if (err)
		return err;

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4385 4386 4387 4388 4389 4390 4391
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
	struct socket *sock = sk->sk_socket;
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4392

L
Linus Torvalds 已提交
4393 4394 4395 4396
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4397
	nlh = nlmsg_hdr(skb);
4398

L
Linus Torvalds 已提交
4399 4400 4401
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4402
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4403 4404 4405
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4406
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422
				err = 0;
		}

		/* Ignore */
		if (err == -ENOENT)
			err = 0;
		goto out;
	}

	err = socket_has_perm(current, sock, perm);
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4423 4424
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4425
{
4426
	int err;
4427 4428
	char *addrp;
	u32 peer_sid;
4429
	struct common_audit_data ad;
4430
	u8 secmark_active;
4431
	u8 netlbl_active;
4432
	u8 peerlbl_active;
4433

4434 4435
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4436

4437
	secmark_active = selinux_secmark_enabled();
4438 4439
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4440 4441
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4442

4443 4444 4445
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4446
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4447 4448 4449 4450 4451
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4452 4453 4454 4455 4456
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4457
			return NF_DROP;
4458 4459
		}
	}
4460 4461 4462 4463 4464 4465

	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
			return NF_DROP;

4466 4467 4468 4469 4470 4471 4472 4473
	if (netlbl_active)
		/* we do this in the FORWARD path and not the POST_ROUTING
		 * path because we want to make sure we apply the necessary
		 * labeling before IPsec is applied so we can leverage AH
		 * protection */
		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
			return NF_DROP;

4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496
	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET);
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
static unsigned int selinux_ipv6_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET6);
}
#endif	/* IPV6 */

4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
	u32 sid;

	if (!netlbl_enabled())
		return NF_ACCEPT;

	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
	 * because we want to make sure we apply the necessary labeling
	 * before IPsec is applied so we can leverage AH protection */
	if (skb->sk) {
		struct sk_security_struct *sksec = skb->sk->sk_security;
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_output(unsigned int hooknum,
					struct sk_buff *skb,
					const struct net_device *in,
					const struct net_device *out,
					int (*okfn)(struct sk_buff *))
{
	return selinux_ip_output(skb, PF_INET);
}

4528 4529
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4530
						u16 family)
4531 4532 4533
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4534
	struct common_audit_data ad;
4535 4536
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4537

4538 4539 4540 4541
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4542
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4543 4544 4545 4546 4547
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4548
	if (selinux_secmark_enabled())
4549
		if (avc_has_perm(sksec->sid, skb->secmark,
4550
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4551 4552 4553
			return NF_DROP;

	if (selinux_policycap_netpeer)
4554
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4555 4556 4557
			return NF_DROP;

	return NF_ACCEPT;
4558 4559
}

4560 4561
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4562
{
4563 4564
	u32 secmark_perm;
	u32 peer_sid;
4565
	struct sock *sk;
4566
	struct common_audit_data ad;
4567 4568 4569
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4570

4571 4572 4573 4574
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_ip_postroute_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
4575
	if (!selinux_policycap_netpeer)
4576
		return selinux_ip_postroute_compat(skb, ifindex, family);
4577
#ifdef CONFIG_XFRM
4578 4579 4580 4581 4582 4583
	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
	 *       is NULL, in this case go ahead and apply access control. */
E
Eric Dumazet 已提交
4584
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4585
		return NF_ACCEPT;
4586
#endif
4587 4588 4589 4590 4591
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4592 4593 4594 4595
	/* if the packet is being forwarded then get the peer label from the
	 * packet itself; otherwise check to see if it is from a local
	 * application or the kernel, if from an application get the peer label
	 * from the sending socket, otherwise use the kernel's sid */
4596
	sk = skb->sk;
4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619
	if (sk == NULL) {
		switch (family) {
		case PF_INET:
			if (IPCB(skb)->flags & IPSKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		case PF_INET6:
			if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		default:
			return NF_DROP;
		}
		if (secmark_perm == PACKET__FORWARD_OUT) {
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
				return NF_DROP;
		} else
			peer_sid = SECINITSID_KERNEL;
	} else {
4620 4621 4622 4623
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4624

4625
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4626 4627 4628 4629 4630
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
		return NF_DROP;

4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
			return NF_DROP;

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
			return NF_DROP;

		if (sel_netnode_sid(addrp, family, &node_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
			return NF_DROP;
	}
4652

4653
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4654 4655
}

4656 4657 4658 4659 4660
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4661
{
4662
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4663 4664 4665
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4666 4667 4668 4669 4670
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4671
{
4672
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4673 4674 4675 4676 4677 4678 4679 4680 4681
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
	int err;

4682
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4683 4684 4685 4686 4687 4688 4689 4690 4691
	if (err)
		return err;

	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
		err = selinux_nlmsg_perm(sk, skb);

	return err;
}

4692
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4693
{
4694
	int err;
4695
	struct common_audit_data ad;
4696

4697
	err = cap_netlink_recv(skb, capability);
4698 4699 4700
	if (err)
		return err;

4701
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4702 4703 4704
	ad.u.cap = capability;

	return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4705
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4706 4707 4708 4709 4710 4711 4712
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4713
	u32 sid;
L
Linus Torvalds 已提交
4714

J
James Morris 已提交
4715
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4716 4717 4718
	if (!isec)
		return -ENOMEM;

4719
	sid = task_sid(task);
L
Linus Torvalds 已提交
4720
	isec->sclass = sclass;
4721
	isec->sid = sid;
L
Linus Torvalds 已提交
4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737
	perm->security = isec;

	return 0;
}

static void ipc_free_security(struct kern_ipc_perm *perm)
{
	struct ipc_security_struct *isec = perm->security;
	perm->security = NULL;
	kfree(isec);
}

static int msg_msg_alloc_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec;

J
James Morris 已提交
4738
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756
	if (!msec)
		return -ENOMEM;

	msec->sid = SECINITSID_UNLABELED;
	msg->security = msec;

	return 0;
}

static void msg_msg_free_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec = msg->security;

	msg->security = NULL;
	kfree(msec);
}

static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4757
			u32 perms)
L
Linus Torvalds 已提交
4758 4759
{
	struct ipc_security_struct *isec;
4760
	struct common_audit_data ad;
4761
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4762 4763 4764

	isec = ipc_perms->security;

4765
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4766 4767
	ad.u.ipc_id = ipc_perms->key;

4768
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784
}

static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
{
	return msg_msg_alloc_security(msg);
}

static void selinux_msg_msg_free_security(struct msg_msg *msg)
{
	msg_msg_free_security(msg);
}

/* message queue security operations */
static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
{
	struct ipc_security_struct *isec;
4785
	struct common_audit_data ad;
4786
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4787 4788 4789 4790 4791 4792 4793 4794
	int rc;

	rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
	if (rc)
		return rc;

	isec = msq->q_perm.security;

4795
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4796
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4797

4798
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814
			  MSGQ__CREATE, &ad);
	if (rc) {
		ipc_free_security(&msq->q_perm);
		return rc;
	}
	return 0;
}

static void selinux_msg_queue_free_security(struct msg_queue *msq)
{
	ipc_free_security(&msq->q_perm);
}

static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	struct ipc_security_struct *isec;
4815
	struct common_audit_data ad;
4816
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4817 4818 4819

	isec = msq->q_perm.security;

4820
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4821 4822
	ad.u.ipc_id = msq->q_perm.key;

4823
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4824 4825 4826 4827 4828 4829 4830 4831
			    MSGQ__ASSOCIATE, &ad);
}

static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
	int err;
	int perms;

4832
	switch (cmd) {
L
Linus Torvalds 已提交
4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850
	case IPC_INFO:
	case MSG_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case IPC_STAT:
	case MSG_STAT:
		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
		break;
	case IPC_SET:
		perms = MSGQ__SETATTR;
		break;
	case IPC_RMID:
		perms = MSGQ__DESTROY;
		break;
	default:
		return 0;
	}

4851
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4852 4853 4854 4855 4856 4857 4858
	return err;
}

static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
4859
	struct common_audit_data ad;
4860
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

	/*
	 * First time through, need to assign label to the message
	 */
	if (msec->sid == SECINITSID_UNLABELED) {
		/*
		 * Compute new sid based on current process and
		 * message queue this message will be stored in
		 */
4874
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
4875 4876 4877 4878 4879
					     &msec->sid);
		if (rc)
			return rc;
	}

4880
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4881 4882 4883
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4884
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4885 4886 4887
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4888 4889
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4890 4891
	if (!rc)
		/* Can the message be put in the queue? */
4892 4893
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4894 4895 4896 4897 4898 4899 4900 4901 4902 4903

	return rc;
}

static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
				    struct task_struct *target,
				    long type, int mode)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
4904
	struct common_audit_data ad;
4905
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4906 4907 4908 4909 4910
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

4911
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4912
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4913

4914
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4915 4916
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4917
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4918 4919 4920 4921 4922 4923 4924 4925
				  SECCLASS_MSG, MSG__RECEIVE, &ad);
	return rc;
}

/* Shared Memory security operations */
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
{
	struct ipc_security_struct *isec;
4926
	struct common_audit_data ad;
4927
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4928 4929 4930 4931 4932 4933 4934 4935
	int rc;

	rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
	if (rc)
		return rc;

	isec = shp->shm_perm.security;

4936
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4937
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4938

4939
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955
			  SHM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&shp->shm_perm);
		return rc;
	}
	return 0;
}

static void selinux_shm_free_security(struct shmid_kernel *shp)
{
	ipc_free_security(&shp->shm_perm);
}

static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
{
	struct ipc_security_struct *isec;
4956
	struct common_audit_data ad;
4957
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4958 4959 4960

	isec = shp->shm_perm.security;

4961
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4962 4963
	ad.u.ipc_id = shp->shm_perm.key;

4964
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4965 4966 4967 4968 4969 4970 4971 4972 4973
			    SHM__ASSOCIATE, &ad);
}

/* Note, at this point, shp is locked down */
static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
	int perms;
	int err;

4974
	switch (cmd) {
L
Linus Torvalds 已提交
4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996
	case IPC_INFO:
	case SHM_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case IPC_STAT:
	case SHM_STAT:
		perms = SHM__GETATTR | SHM__ASSOCIATE;
		break;
	case IPC_SET:
		perms = SHM__SETATTR;
		break;
	case SHM_LOCK:
	case SHM_UNLOCK:
		perms = SHM__LOCK;
		break;
	case IPC_RMID:
		perms = SHM__DESTROY;
		break;
	default:
		return 0;
	}

4997
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010
	return err;
}

static int selinux_shm_shmat(struct shmid_kernel *shp,
			     char __user *shmaddr, int shmflg)
{
	u32 perms;

	if (shmflg & SHM_RDONLY)
		perms = SHM__READ;
	else
		perms = SHM__READ | SHM__WRITE;

5011
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5012 5013 5014 5015 5016 5017
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5018
	struct common_audit_data ad;
5019
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5020 5021 5022 5023 5024 5025 5026 5027
	int rc;

	rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
	if (rc)
		return rc;

	isec = sma->sem_perm.security;

5028
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5029
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5030

5031
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047
			  SEM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&sma->sem_perm);
		return rc;
	}
	return 0;
}

static void selinux_sem_free_security(struct sem_array *sma)
{
	ipc_free_security(&sma->sem_perm);
}

static int selinux_sem_associate(struct sem_array *sma, int semflg)
{
	struct ipc_security_struct *isec;
5048
	struct common_audit_data ad;
5049
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5050 5051 5052

	isec = sma->sem_perm.security;

5053
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
5054 5055
	ad.u.ipc_id = sma->sem_perm.key;

5056
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5057 5058 5059 5060 5061 5062 5063 5064 5065
			    SEM__ASSOCIATE, &ad);
}

/* Note, at this point, sma is locked down */
static int selinux_sem_semctl(struct sem_array *sma, int cmd)
{
	int err;
	u32 perms;

5066
	switch (cmd) {
L
Linus Torvalds 已提交
5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097
	case IPC_INFO:
	case SEM_INFO:
		/* No specific object, just general system-wide information. */
		return task_has_system(current, SYSTEM__IPC_INFO);
	case GETPID:
	case GETNCNT:
	case GETZCNT:
		perms = SEM__GETATTR;
		break;
	case GETVAL:
	case GETALL:
		perms = SEM__READ;
		break;
	case SETVAL:
	case SETALL:
		perms = SEM__WRITE;
		break;
	case IPC_RMID:
		perms = SEM__DESTROY;
		break;
	case IPC_SET:
		perms = SEM__SETATTR;
		break;
	case IPC_STAT:
	case SEM_STAT:
		perms = SEM__GETATTR | SEM__ASSOCIATE;
		break;
	default:
		return 0;
	}

5098
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111
	return err;
}

static int selinux_sem_semop(struct sem_array *sma,
			     struct sembuf *sops, unsigned nsops, int alter)
{
	u32 perms;

	if (alter)
		perms = SEM__READ | SEM__WRITE;
	else
		perms = SEM__READ;

5112
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127
}

static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
{
	u32 av = 0;

	av = 0;
	if (flag & S_IRUGO)
		av |= IPC__UNIX_READ;
	if (flag & S_IWUGO)
		av |= IPC__UNIX_WRITE;

	if (av == 0)
		return 0;

5128
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5129 5130
}

5131 5132 5133 5134 5135 5136
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5137
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5138 5139 5140 5141 5142 5143
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5144
			       char *name, char **value)
L
Linus Torvalds 已提交
5145
{
5146
	const struct task_security_struct *__tsec;
5147
	u32 sid;
L
Linus Torvalds 已提交
5148
	int error;
5149
	unsigned len;
L
Linus Torvalds 已提交
5150 5151

	if (current != p) {
5152
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5153 5154 5155 5156
		if (error)
			return error;
	}

5157 5158
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5159 5160

	if (!strcmp(name, "current"))
5161
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5162
	else if (!strcmp(name, "prev"))
5163
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5164
	else if (!strcmp(name, "exec"))
5165
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5166
	else if (!strcmp(name, "fscreate"))
5167
		sid = __tsec->create_sid;
5168
	else if (!strcmp(name, "keycreate"))
5169
		sid = __tsec->keycreate_sid;
5170
	else if (!strcmp(name, "sockcreate"))
5171
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5172
	else
5173 5174
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5175 5176 5177 5178

	if (!sid)
		return 0;

5179 5180 5181 5182
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5183 5184 5185 5186

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5187 5188 5189 5190 5191 5192
}

static int selinux_setprocattr(struct task_struct *p,
			       char *name, void *value, size_t size)
{
	struct task_security_struct *tsec;
R
Roland McGrath 已提交
5193
	struct task_struct *tracer;
D
David Howells 已提交
5194 5195
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210
	int error;
	char *str = value;

	if (current != p) {
		/* SELinux only allows a process to change its own
		   security attributes. */
		return -EACCES;
	}

	/*
	 * Basic control over ability to set these attributes at all.
	 * current == p, but we'll pass them separately in case the
	 * above restriction is ever removed.
	 */
	if (!strcmp(name, "exec"))
5211
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5212
	else if (!strcmp(name, "fscreate"))
5213
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5214
	else if (!strcmp(name, "keycreate"))
5215
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5216
	else if (!strcmp(name, "sockcreate"))
5217
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5218
	else if (!strcmp(name, "current"))
5219
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
	if (size && str[1] && str[1] != '\n') {
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
		error = security_context_to_sid(value, size, &sid);
5232 5233 5234 5235 5236 5237
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5238 5239 5240 5241
		if (error)
			return error;
	}

D
David Howells 已提交
5242 5243 5244 5245
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5246 5247 5248
	/* Permission checking based on the specified context is
	   performed during the actual operation (execve,
	   open/mkdir/...), when we know the full context of the
D
David Howells 已提交
5249
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5250 5251
	   checks and may_create for the file creation checks. The
	   operation will then fail if the context is not permitted. */
D
David Howells 已提交
5252 5253
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5254
		tsec->exec_sid = sid;
D
David Howells 已提交
5255
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5256
		tsec->create_sid = sid;
D
David Howells 已提交
5257
	} else if (!strcmp(name, "keycreate")) {
5258 5259
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5260
			goto abort_change;
5261
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5262
	} else if (!strcmp(name, "sockcreate")) {
5263
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5264 5265
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5266
		if (sid == 0)
D
David Howells 已提交
5267 5268 5269 5270
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5271
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5272 5273 5274
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5275
		}
L
Linus Torvalds 已提交
5276 5277 5278

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5279
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5280
		if (error)
D
David Howells 已提交
5281
			goto abort_change;
L
Linus Torvalds 已提交
5282 5283 5284

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5285
		ptsid = 0;
L
Linus Torvalds 已提交
5286
		task_lock(p);
5287
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5288 5289 5290 5291 5292 5293 5294
		if (tracer)
			ptsid = task_sid(tracer);
		task_unlock(p);

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5295
			if (error)
D
David Howells 已提交
5296
				goto abort_change;
L
Linus Torvalds 已提交
5297 5298
		}

D
David Howells 已提交
5299 5300 5301 5302 5303 5304 5305
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5306
	return size;
D
David Howells 已提交
5307 5308 5309 5310

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5311 5312
}

5313 5314 5315 5316 5317
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5318
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5319 5320 5321 5322
{
	return security_context_to_sid(secdata, seclen, secid);
}

5323 5324
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5325
	kfree(secdata);
5326 5327
}

5328 5329
#ifdef CONFIG_KEYS

D
David Howells 已提交
5330
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5331
			     unsigned long flags)
5332
{
D
David Howells 已提交
5333
	const struct task_security_struct *tsec;
5334 5335 5336 5337 5338 5339
	struct key_security_struct *ksec;

	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
	if (!ksec)
		return -ENOMEM;

D
David Howells 已提交
5340 5341 5342
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5343
	else
D
David Howells 已提交
5344
		ksec->sid = tsec->sid;
5345

5346
	k->security = ksec;
5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358
	return 0;
}

static void selinux_key_free(struct key *k)
{
	struct key_security_struct *ksec = k->security;

	k->security = NULL;
	kfree(ksec);
}

static int selinux_key_permission(key_ref_t key_ref,
D
David Howells 已提交
5359 5360
				  const struct cred *cred,
				  key_perm_t perm)
5361 5362 5363
{
	struct key *key;
	struct key_security_struct *ksec;
5364
	u32 sid;
5365 5366 5367 5368 5369 5370 5371

	/* if no specific permissions are requested, we skip the
	   permission check. No serious, additional covert channels
	   appear to be created. */
	if (perm == 0)
		return 0;

D
David Howells 已提交
5372
	sid = cred_sid(cred);
5373 5374 5375 5376 5377

	key = key_ref_to_ptr(key_ref);
	ksec = key->security;

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5378 5379
}

5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393
static int selinux_key_getsecurity(struct key *key, char **_buffer)
{
	struct key_security_struct *ksec = key->security;
	char *context = NULL;
	unsigned len;
	int rc;

	rc = security_sid_to_context(ksec->sid, &context, &len);
	if (!rc)
		rc = len;
	*_buffer = context;
	return rc;
}

5394 5395
#endif

L
Linus Torvalds 已提交
5396
static struct security_operations selinux_ops = {
5397 5398
	.name =				"selinux",

5399
	.ptrace_access_check =		selinux_ptrace_access_check,
5400
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5401
	.capget =			selinux_capget,
D
David Howells 已提交
5402
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5403 5404 5405 5406 5407 5408 5409 5410
	.sysctl =			selinux_sysctl,
	.capable =			selinux_capable,
	.quotactl =			selinux_quotactl,
	.quota_on =			selinux_quota_on,
	.syslog =			selinux_syslog,
	.vm_enough_memory =		selinux_vm_enough_memory,

	.netlink_send =			selinux_netlink_send,
5411
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5412

5413 5414 5415
	.bprm_set_creds =		selinux_bprm_set_creds,
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5416 5417 5418 5419 5420
	.bprm_secureexec =		selinux_bprm_secureexec,

	.sb_alloc_security =		selinux_sb_alloc_security,
	.sb_free_security =		selinux_sb_free_security,
	.sb_copy_data =			selinux_sb_copy_data,
5421
	.sb_kern_mount =		selinux_sb_kern_mount,
5422
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5423 5424 5425
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5426
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5427
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5428 5429
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5430 5431 5432

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5433
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449 5450 5451
	.inode_create =			selinux_inode_create,
	.inode_link =			selinux_inode_link,
	.inode_unlink =			selinux_inode_unlink,
	.inode_symlink =		selinux_inode_symlink,
	.inode_mkdir =			selinux_inode_mkdir,
	.inode_rmdir =			selinux_inode_rmdir,
	.inode_mknod =			selinux_inode_mknod,
	.inode_rename =			selinux_inode_rename,
	.inode_readlink =		selinux_inode_readlink,
	.inode_follow_link =		selinux_inode_follow_link,
	.inode_permission =		selinux_inode_permission,
	.inode_setattr =		selinux_inode_setattr,
	.inode_getattr =		selinux_inode_getattr,
	.inode_setxattr =		selinux_inode_setxattr,
	.inode_post_setxattr =		selinux_inode_post_setxattr,
	.inode_getxattr =		selinux_inode_getxattr,
	.inode_listxattr =		selinux_inode_listxattr,
	.inode_removexattr =		selinux_inode_removexattr,
5452 5453 5454
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5455
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
	.file_mmap =			selinux_file_mmap,
	.file_mprotect =		selinux_file_mprotect,
	.file_lock =			selinux_file_lock,
	.file_fcntl =			selinux_file_fcntl,
	.file_set_fowner =		selinux_file_set_fowner,
	.file_send_sigiotask =		selinux_file_send_sigiotask,
	.file_receive =			selinux_file_receive,

5469
	.dentry_open =			selinux_dentry_open,
5470

L
Linus Torvalds 已提交
5471
	.task_create =			selinux_task_create,
5472
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5473
	.cred_prepare =			selinux_cred_prepare,
5474 5475
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5476
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5477 5478
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5479
	.task_getsid =			selinux_task_getsid,
5480
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5481
	.task_setnice =			selinux_task_setnice,
5482
	.task_setioprio =		selinux_task_setioprio,
5483
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5484 5485 5486
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5487
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5488 5489
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5490
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5491 5492

	.ipc_permission =		selinux_ipc_permission,
5493
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510

	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
	.msg_msg_free_security =	selinux_msg_msg_free_security,

	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
	.msg_queue_free_security =	selinux_msg_queue_free_security,
	.msg_queue_associate =		selinux_msg_queue_associate,
	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,

	.shm_alloc_security =		selinux_shm_alloc_security,
	.shm_free_security =		selinux_shm_free_security,
	.shm_associate =		selinux_shm_associate,
	.shm_shmctl =			selinux_shm_shmctl,
	.shm_shmat =			selinux_shm_shmat,

5511 5512
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5513 5514 5515 5516
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5517
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5518

5519 5520
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5521

5522
	.secid_to_secctx =		selinux_secid_to_secctx,
5523
	.secctx_to_secid =		selinux_secctx_to_secid,
5524 5525
	.release_secctx =		selinux_release_secctx,

5526
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542
	.unix_may_send =		selinux_socket_unix_may_send,

	.socket_create =		selinux_socket_create,
	.socket_post_create =		selinux_socket_post_create,
	.socket_bind =			selinux_socket_bind,
	.socket_connect =		selinux_socket_connect,
	.socket_listen =		selinux_socket_listen,
	.socket_accept =		selinux_socket_accept,
	.socket_sendmsg =		selinux_socket_sendmsg,
	.socket_recvmsg =		selinux_socket_recvmsg,
	.socket_getsockname =		selinux_socket_getsockname,
	.socket_getpeername =		selinux_socket_getpeername,
	.socket_getsockopt =		selinux_socket_getsockopt,
	.socket_setsockopt =		selinux_socket_setsockopt,
	.socket_shutdown =		selinux_socket_shutdown,
	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
C
Catherine Zhang 已提交
5543 5544
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5545 5546
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5547
	.sk_clone_security =		selinux_sk_clone_security,
5548
	.sk_getsecid =			selinux_sk_getsecid,
5549 5550 5551
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5552
	.inet_conn_established =	selinux_inet_conn_established,
5553
	.req_classify_flow =		selinux_req_classify_flow,
5554 5555 5556
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5557 5558 5559 5560 5561

#ifdef CONFIG_SECURITY_NETWORK_XFRM
	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
C
Catherine Zhang 已提交
5562
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5563 5564
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5565
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5566
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5567 5568
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5569
#endif
5570 5571

#ifdef CONFIG_KEYS
5572 5573 5574
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5575
	.key_getsecurity =		selinux_key_getsecurity,
5576
#endif
5577 5578 5579 5580 5581 5582 5583

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
Linus Torvalds 已提交
5584 5585 5586 5587
};

static __init int selinux_init(void)
{
5588 5589 5590 5591 5592
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5593 5594 5595 5596 5597 5598 5599 5600
	if (!selinux_enabled) {
		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
		return 0;
	}

	printk(KERN_INFO "SELinux:  Initializing.\n");

	/* Set the security state for the initial task. */
D
David Howells 已提交
5601
	cred_init_security();
L
Linus Torvalds 已提交
5602

5603 5604
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5605
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5606 5607
	avc_init();

5608
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5609
	if (!secondary_ops)
5610 5611
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5612 5613
		panic("SELinux: Unable to register with kernel.\n");

5614
	if (selinux_enforcing)
5615
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5616
	else
5617
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5618

L
Linus Torvalds 已提交
5619 5620 5621 5622 5623
	return 0;
}

void selinux_complete_init(void)
{
5624
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5625 5626

	/* Set up any superblocks initialized prior to the policy load. */
5627
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5628
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5629 5630 5631 5632 5633
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5634 5635
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5636 5637 5638
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5639
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5640 5641 5642 5643
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5644
		spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5645 5646 5647 5648 5649
		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5650
	spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5651 5652 5653 5654 5655 5656
}

/* SELinux requires early initialization in order to label
   all processes and objects when they are created. */
security_initcall(selinux_init);

5657
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5658

5659 5660 5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671 5672
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5673 5674 5675 5676 5677 5678 5679
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5680
	}
L
Linus Torvalds 已提交
5681 5682 5683 5684
};

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)

5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5700 5701 5702 5703 5704 5705 5706 5707 5708 5709
};

#endif	/* IPV6 */

static int __init selinux_nf_ip_init(void)
{
	int err = 0;

	if (!selinux_enabled)
		goto out;
5710 5711 5712

	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");

5713 5714 5715
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
5716 5717

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5718 5719 5720
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
5721
#endif	/* IPV6 */
5722

L
Linus Torvalds 已提交
5723 5724 5725 5726 5727 5728 5729 5730 5731
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5732
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5733

5734
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5735
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5736
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5737 5738 5739 5740
#endif	/* IPV6 */
}
#endif

5741
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5742 5743 5744 5745 5746

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5747
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5748 5749

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5750 5751
static int selinux_disabled;

L
Linus Torvalds 已提交
5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767 5768
int selinux_disable(void)
{
	extern void exit_sel_fs(void);

	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

	if (selinux_disabled) {
		/* Only do this once. */
		return -EINVAL;
	}

	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");

	selinux_disabled = 1;
5769
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5770

5771 5772 5773
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785
	/* Reset security_ops to the secondary module, dummy or capability. */
	security_ops = secondary_ops;

	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif