hooks.c 158.8 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.
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 *	Paul Moore <paul@paul-moore.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>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
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#include <linux/lsm_hooks.h>
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#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>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#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/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/inet_connection_sock.h>
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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 <linux/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
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#include <net/netlink.h>
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#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/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 <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.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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#include "avc_ss.h"
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/* SECMARK reference count */
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static 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;
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	if (!kstrtoul(str, 0, &enforcing))
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		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;
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	if (!kstrtoul(str, 0, &enabled))
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		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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static struct kmem_cache *sel_inode_cache;
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static struct kmem_cache *file_security_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
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 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 * policy capability is enabled, SECMARK is always considered enabled.
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 *
 */
static int selinux_secmark_enabled(void)
{
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	return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
}

/**
 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 *
 * Description:
 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 * (1) if any are enabled or false (0) if neither are enabled.  If the
 * always_check_network policy capability is enabled, peer labeling
 * is always considered enabled.
 *
 */
static int selinux_peerlbl_enabled(void)
{
	return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
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}

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static int selinux_netcache_avc_callback(u32 event)
{
	if (event == AVC_CALLBACK_RESET) {
		sel_netif_flush();
		sel_netnode_flush();
		sel_netport_flush();
		synchronize_net();
	}
	return 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)
{
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	const struct task_security_struct *tsec = current_security();
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	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;
}

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

/*
 * Try reloading inode security labels that have been marked as invalid.  The
 * @may_sleep parameter indicates when sleeping and thus reloading labels is
 * allowed; when set to false, returns ERR_PTR(-ECHILD) when the label is
 * invalid.  The @opt_dentry parameter should be set to a dentry of the inode;
 * when no dentry is available, set it to NULL instead.
 */
static int __inode_security_revalidate(struct inode *inode,
				       struct dentry *opt_dentry,
				       bool may_sleep)
{
	struct inode_security_struct *isec = inode->i_security;

	might_sleep_if(may_sleep);

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	if (isec->initialized != LABEL_INITIALIZED) {
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		if (!may_sleep)
			return -ECHILD;

		/*
		 * Try reloading the inode security label.  This will fail if
		 * @opt_dentry is NULL and no dentry for this inode can be
		 * found; in that case, continue using the old label.
		 */
		inode_doinit_with_dentry(inode, opt_dentry);
	}
	return 0;
}

static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
{
	return inode->i_security;
}

static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
{
	int error;

	error = __inode_security_revalidate(inode, NULL, !rcu);
	if (error)
		return ERR_PTR(error);
	return inode->i_security;
}

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/*
 * Get the security label of an inode.
 */
static struct inode_security_struct *inode_security(struct inode *inode)
{
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	__inode_security_revalidate(inode, NULL, true);
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	return inode->i_security;
}

/*
 * Get the security label of a dentry's backing inode.
 */
static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
{
	struct inode *inode = d_backing_inode(dentry);

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	__inode_security_revalidate(inode, dentry, true);
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	return inode->i_security;
}

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static void inode_free_rcu(struct rcu_head *head)
{
	struct inode_security_struct *isec;

	isec = container_of(head, struct inode_security_struct, rcu);
	kmem_cache_free(sel_inode_cache, isec);
}

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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;

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	/*
	 * As not all inode security structures are in a list, we check for
	 * empty list outside of the lock to make sure that we won't waste
	 * time taking a lock doing nothing.
	 *
	 * The list_del_init() function can be safely called more than once.
	 * It should not be possible for this function to be called with
	 * concurrent list_add(), but for better safety against future changes
	 * in the code, we use list_empty_careful() here.
	 */
	if (!list_empty_careful(&isec->list)) {
		spin_lock(&sbsec->isec_lock);
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		list_del_init(&isec->list);
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		spin_unlock(&sbsec->isec_lock);
	}
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	/*
	 * The inode may still be referenced in a path walk and
	 * a call to selinux_inode_permission() can be made
	 * after inode_free_security() is called. Ideally, the VFS
	 * wouldn't do this, but fixing that is a much harder
	 * job. For now, simply free the i_security via RCU, and
	 * leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&isec->rcu, inode_free_rcu);
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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 = kmem_cache_zalloc(file_security_cache, 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;
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	kmem_cache_free(file_security_cache, fsec);
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}

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

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

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static const char *labeling_behaviors[7] = {
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	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
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	"uses native labeling",
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};

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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	Opt_nextmntopt = 6,
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};

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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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 selinux_is_sblabel_mnt(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

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	return sbsec->behavior == SECURITY_FS_USE_XATTR ||
		sbsec->behavior == SECURITY_FS_USE_TRANS ||
		sbsec->behavior == SECURITY_FS_USE_TASK ||
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		sbsec->behavior == SECURITY_FS_USE_NATIVE ||
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		/* Special handling. Genfs but also in-core setxattr handler */
		!strcmp(sb->s_type->name, "sysfs") ||
		!strcmp(sb->s_type->name, "pstore") ||
		!strcmp(sb->s_type->name, "debugfs") ||
		!strcmp(sb->s_type->name, "rootfs");
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}

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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;
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	struct inode *root_inode = d_backing_inode(root);
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	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) {
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			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
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			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 "
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				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
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			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
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				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
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			goto out;
		}
	}
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	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
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		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
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	sbsec->flags |= SE_SBINITIALIZED;
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	if (selinux_is_sblabel_mnt(sb))
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		sbsec->flags |= SBLABEL_MNT;
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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;
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		list_del_init(&isec->list);
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		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		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;
L
Linus Torvalds 已提交
579

580 581
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
582

583 584 585
	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

586
	tmp = sbsec->flags & SE_MNTMASK;
587
	/* count the number of mount options for this sb */
588
	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
589
		if (tmp & 0x01)
590
			opts->num_mnt_opts++;
591 592
		tmp >>= 1;
	}
593
	/* Check if the Label support flag is set */
594
	if (sbsec->flags & SBLABEL_MNT)
595
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
596

597 598
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
599 600 601
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
602

603 604
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
605 606 607
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
608

609 610 611 612 613
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
614 615
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
616 617 618 619 620
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
621 622
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
623 624 625 626 627
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
628 629
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
630 631
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
632 633
		struct dentry *root = sbsec->sb->s_root;
		struct inode_security_struct *isec = backing_inode_security(root);
634

635 636 637
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
638 639
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
640
	}
641
	if (sbsec->flags & SBLABEL_MNT) {
642
		opts->mnt_opts[i] = NULL;
643
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
644
	}
L
Linus Torvalds 已提交
645

646
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
647

648 649 650
	return 0;

out_free:
651
	security_free_mnt_opts(opts);
652 653
	return rc;
}
L
Linus Torvalds 已提交
654

655 656 657
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
658 659
	char mnt_flags = sbsec->flags & SE_MNTMASK;

660
	/* check if the old mount command had the same options */
661
	if (sbsec->flags & SE_SBINITIALIZED)
662 663 664 665 666 667 668
		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
	 */
669 670
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
671 672 673
			return 1;
	return 0;
}
674

675 676 677 678
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
679
static int selinux_set_mnt_opts(struct super_block *sb,
680 681 682
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
683
{
684
	const struct cred *cred = current_cred();
685 686
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
687
	const char *name = sb->s_type->name;
688 689
	struct dentry *root = sbsec->sb->s_root;
	struct inode_security_struct *root_isec = backing_inode_security(root);
690 691
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
692 693 694
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
695 696 697 698 699 700 701 702 703 704 705

	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. */
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
706 707
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
708
		goto out;
709
	}
710 711 712 713 714 715
	if (kern_flags && !set_kern_flags) {
		/* Specifying internal flags without providing a place to
		 * place the results is not allowed */
		rc = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
716

717 718 719 720 721 722 723 724 725 726 727
	/*
	 * 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)
	 */
728
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
729
	    && (num_opts == 0))
730
		goto out;
731

732 733 734 735 736 737 738
	/*
	 * 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;
739

740
		if (flags[i] == SBLABEL_MNT)
741
			continue;
742
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
743
		if (rc) {
744
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
745 746
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790
			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
791
		}
792 793
	}

794
	if (sbsec->flags & SE_SBINITIALIZED) {
795
		/* previously mounted with options, but not on this attempt? */
796
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
797 798 799 800 801
			goto out_double_mount;
		rc = 0;
		goto out;
	}

802
	if (strcmp(sb->s_type->name, "proc") == 0)
803 804
		sbsec->flags |= SE_SBPROC | SE_SBGENFS;

805 806 807
	if (!strcmp(sb->s_type->name, "debugfs") ||
	    !strcmp(sb->s_type->name, "sysfs") ||
	    !strcmp(sb->s_type->name, "pstore"))
808
		sbsec->flags |= SE_SBGENFS;
809

810 811 812 813 814
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
815
		rc = security_fs_use(sb);
816 817 818 819 820 821
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
822 823 824
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
825
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
826
		if (rc)
827
			goto out;
L
Linus Torvalds 已提交
828

829
		sbsec->sid = fscontext_sid;
830 831 832 833 834 835 836
	}

	/*
	 * 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.
	 */
837 838 839 840 841
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

842 843
	if (context_sid) {
		if (!fscontext_sid) {
844 845
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
846
			if (rc)
847 848
				goto out;
			sbsec->sid = context_sid;
849
		} else {
850 851
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
852
			if (rc)
853
				goto out;
854
		}
855 856
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
857

858
		sbsec->mntpoint_sid = context_sid;
859
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
860 861
	}

862
	if (rootcontext_sid) {
863 864
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
865
		if (rc)
866
			goto out;
867

868
		root_isec->sid = rootcontext_sid;
869
		root_isec->initialized = LABEL_INITIALIZED;
870 871
	}

872
	if (defcontext_sid) {
873 874
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
875 876 877 878
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
879 880
		}

881 882
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
883
							     sbsec, cred);
884 885 886
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
887

888
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
889 890
	}

891
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
892
out:
893
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
894
	return rc;
895 896 897
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
898
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
899
	goto out;
L
Linus Torvalds 已提交
900 901
}

902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918
static int selinux_cmp_sb_context(const struct super_block *oldsb,
				    const struct super_block *newsb)
{
	struct superblock_security_struct *old = oldsb->s_security;
	struct superblock_security_struct *new = newsb->s_security;
	char oldflags = old->flags & SE_MNTMASK;
	char newflags = new->flags & SE_MNTMASK;

	if (oldflags != newflags)
		goto mismatch;
	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
		goto mismatch;
	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
		goto mismatch;
	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
		goto mismatch;
	if (oldflags & ROOTCONTEXT_MNT) {
919 920
		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
921 922 923 924 925 926 927 928 929 930 931 932
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
			    "different security settings for (dev %s, "
			    "type %s)\n", newsb->s_id, newsb->s_type->name);
	return -EBUSY;
}

static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
933
					struct super_block *newsb)
L
Linus Torvalds 已提交
934
{
935 936
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
937

938 939 940
	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
941

942 943
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
944
	 * mount options.  thus we can safely deal with this superblock later
945
	 */
946
	if (!ss_initialized)
947
		return 0;
948 949

	/* how can we clone if the old one wasn't set up?? */
950
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
951

952
	/* if fs is reusing a sb, make sure that the contexts match */
953
	if (newsbsec->flags & SE_SBINITIALIZED)
954
		return selinux_cmp_sb_context(oldsb, newsb);
955

956 957 958 959 960 961 962 963 964 965 966 967 968 969
	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) {
970
			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
971 972 973
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
974
	}
975
	if (set_rootcontext) {
976 977
		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
L
Linus Torvalds 已提交
978

979
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
980 981
	}

982 983
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
984
	return 0;
985 986
}

987 988
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
989
{
990
	char *p;
991 992
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
993
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
994

995
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
996

997 998 999 1000
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
1001

1002 1003
		if (!*p)
			continue;
L
Linus Torvalds 已提交
1004

1005
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
1006

1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
		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;
1059 1060
		case Opt_labelsupport:
			break;
1061 1062 1063 1064
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
1065 1066 1067

		}
	}
1068

1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079
	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;
	}

1080
	if (fscontext) {
1081 1082
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1083 1084
	}
	if (context) {
1085 1086
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1087 1088
	}
	if (rootcontext) {
1089 1090
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1091 1092
	}
	if (defcontext) {
1093 1094
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1095 1096
	}

1097 1098 1099
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1100 1101 1102 1103 1104
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1105 1106
	return rc;
}
1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
/*
 * 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:
1128
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1129 1130 1131 1132 1133

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1134

A
Adrian Bunk 已提交
1135 1136
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1137 1138 1139 1140 1141
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1142 1143 1144 1145 1146 1147
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161

		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;
1162
		case SBLABEL_MNT:
1163 1164 1165
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1166 1167
		default:
			BUG();
1168
			return;
1169 1170 1171 1172 1173 1174
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
1175
		seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186
		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);
1187 1188 1189 1190
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1191
		return rc;
1192
	}
1193 1194 1195 1196 1197 1198 1199 1200

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223
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;
}

1224 1225 1226 1227 1228 1229 1230 1231 1232 1233
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
1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
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:
1250 1251 1252 1253
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1254
		case SOCK_DGRAM:
1255 1256 1257 1258
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1259 1260
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1261
		default:
L
Linus Torvalds 已提交
1262 1263 1264 1265 1266 1267 1268
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
1269
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1270 1271 1272 1273 1274 1275 1276
			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;
1277 1278
		case NETLINK_ISCSI:
			return SECCLASS_NETLINK_ISCSI_SOCKET;
L
Linus Torvalds 已提交
1279 1280
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
1281 1282 1283 1284 1285 1286
		case NETLINK_FIB_LOOKUP:
			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
		case NETLINK_CONNECTOR:
			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
		case NETLINK_NETFILTER:
			return SECCLASS_NETLINK_NETFILTER_SOCKET;
L
Linus Torvalds 已提交
1287 1288
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1289 1290
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1291 1292 1293 1294 1295 1296 1297 1298
		case NETLINK_GENERIC:
			return SECCLASS_NETLINK_GENERIC_SOCKET;
		case NETLINK_SCSITRANSPORT:
			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
		case NETLINK_RDMA:
			return SECCLASS_NETLINK_RDMA_SOCKET;
		case NETLINK_CRYPTO:
			return SECCLASS_NETLINK_CRYPTO_SOCKET;
L
Linus Torvalds 已提交
1299 1300 1301 1302 1303 1304 1305
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1306 1307
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1308 1309 1310 1311 1312
	}

	return SECCLASS_SOCKET;
}

1313 1314 1315 1316
static int selinux_genfs_get_sid(struct dentry *dentry,
				 u16 tclass,
				 u16 flags,
				 u32 *sid)
L
Linus Torvalds 已提交
1317
{
1318
	int rc;
1319
	struct super_block *sb = dentry->d_inode->i_sb;
1320
	char *buffer, *path;
L
Linus Torvalds 已提交
1321

1322
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1323 1324 1325
	if (!buffer)
		return -ENOMEM;

1326 1327 1328 1329
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
1330 1331 1332 1333 1334 1335 1336 1337
		if (flags & SE_SBPROC) {
			/* each process gets a /proc/PID/ entry. Strip off the
			 * PID part to get a valid selinux labeling.
			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
			while (path[1] >= '0' && path[1] <= '9') {
				path[1] = '/';
				path++;
			}
1338
		}
1339
		rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
L
Linus Torvalds 已提交
1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356
	}
	free_page((unsigned long)buffer);
	return rc;
}

/* 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;

1357
	if (isec->initialized == LABEL_INITIALIZED)
L
Linus Torvalds 已提交
1358 1359
		goto out;

1360
	mutex_lock(&isec->lock);
1361
	if (isec->initialized == LABEL_INITIALIZED)
1362
		goto out_unlock;
L
Linus Torvalds 已提交
1363 1364

	sbsec = inode->i_sb->s_security;
1365
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1366 1367 1368 1369 1370 1371 1372
		/* 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);
1373
		goto out_unlock;
L
Linus Torvalds 已提交
1374 1375 1376
	}

	switch (sbsec->behavior) {
1377 1378
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394
	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) {
1395 1396 1397 1398 1399 1400 1401 1402 1403
			/*
			 * 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.
			 */
1404
			goto out_unlock;
L
Linus Torvalds 已提交
1405 1406 1407
		}

		len = INITCONTEXTLEN;
1408
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1409 1410 1411
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1412
			goto out_unlock;
L
Linus Torvalds 已提交
1413
		}
1414
		context[len] = '\0';
L
Linus Torvalds 已提交
1415 1416 1417
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1418 1419
			kfree(context);

L
Linus Torvalds 已提交
1420 1421 1422 1423 1424
			/* 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);
1425
				goto out_unlock;
L
Linus Torvalds 已提交
1426 1427
			}
			len = rc;
1428
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1429 1430 1431
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1432
				goto out_unlock;
L
Linus Torvalds 已提交
1433
			}
1434
			context[len] = '\0';
L
Linus Torvalds 已提交
1435 1436 1437 1438 1439 1440 1441
			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
1442
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1443
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1444 1445
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1446
				goto out_unlock;
L
Linus Torvalds 已提交
1447 1448 1449 1450 1451
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1452
			rc = security_context_to_sid_default(context, rc, &sid,
1453 1454
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1455
			if (rc) {
1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468
				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
1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486
				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);
1487 1488
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1489
		if (rc)
1490
			goto out_unlock;
L
Linus Torvalds 已提交
1491 1492
		isec->sid = sid;
		break;
1493 1494 1495
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1496
	default:
1497
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1498 1499
		isec->sid = sbsec->sid;

1500
		if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522
			/* We must have a dentry to determine the label on
			 * procfs inodes */
			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);
			/*
			 * This 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.
			 */
			if (!dentry)
				goto out_unlock;
			isec->sclass = inode_mode_to_security_class(inode->i_mode);
1523 1524
			rc = selinux_genfs_get_sid(dentry, isec->sclass,
						   sbsec->flags, &sid);
1525 1526 1527 1528
			dput(dentry);
			if (rc)
				goto out_unlock;
			isec->sid = sid;
L
Linus Torvalds 已提交
1529 1530 1531 1532
		}
		break;
	}

1533
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
1534

1535 1536
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569
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
1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582
/*
 * 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);
}

1583
/*
1584
 * Check permission between a pair of tasks, e.g. signal checks,
1585 1586
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1587
 * - this uses the default subjective creds of tsk1
1588 1589 1590
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1591 1592
			 u32 perms)
{
1593 1594
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1595

1596 1597 1598 1599 1600
	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
1601 1602
}

1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618
/*
 * 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);
}

1619 1620 1621 1622
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1623
/* Check whether a task is allowed to use a capability. */
1624
static int cred_has_capability(const struct cred *cred,
1625
			       int cap, int audit)
L
Linus Torvalds 已提交
1626
{
1627
	struct common_audit_data ad;
1628
	struct av_decision avd;
1629
	u16 sclass;
1630
	u32 sid = cred_sid(cred);
1631
	u32 av = CAP_TO_MASK(cap);
1632
	int rc;
L
Linus Torvalds 已提交
1633

1634
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1635 1636
	ad.u.cap = cap;

1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647
	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();
1648
		return -EINVAL;
1649
	}
1650

1651
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1652
	if (audit == SECURITY_CAP_AUDIT) {
1653
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1654 1655 1656
		if (rc2)
			return rc2;
	}
1657
	return rc;
L
Linus Torvalds 已提交
1658 1659 1660 1661 1662 1663
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1664
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1665

1666
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1667 1668 1669 1670 1671 1672
			    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). */
1673
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1674 1675
			  struct inode *inode,
			  u32 perms,
1676
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1677 1678
{
	struct inode_security_struct *isec;
1679
	u32 sid;
L
Linus Torvalds 已提交
1680

1681 1682
	validate_creds(cred);

1683
	if (unlikely(IS_PRIVATE(inode)))
1684 1685
		return 0;

1686
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1687 1688
	isec = inode->i_security;

1689
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1690 1691 1692 1693 1694
}

/* 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. */
1695
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1696 1697 1698
				  struct dentry *dentry,
				  u32 av)
{
1699
	struct inode *inode = d_backing_inode(dentry);
1700
	struct common_audit_data ad;
1701

1702
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1703
	ad.u.dentry = dentry;
1704
	__inode_security_revalidate(inode, dentry, true);
1705
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1706 1707 1708 1709 1710 1711
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the path to help the auditing code to more easily generate the
   pathname if needed. */
static inline int path_has_perm(const struct cred *cred,
1712
				const struct path *path,
E
Eric Paris 已提交
1713 1714
				u32 av)
{
1715
	struct inode *inode = d_backing_inode(path->dentry);
E
Eric Paris 已提交
1716 1717
	struct common_audit_data ad;

1718
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1719
	ad.u.path = *path;
1720
	__inode_security_revalidate(inode, path->dentry, true);
1721
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1722 1723
}

1724 1725 1726 1727 1728 1729 1730 1731 1732
/* Same as path_has_perm, but uses the inode from the file struct. */
static inline int file_path_has_perm(const struct cred *cred,
				     struct file *file,
				     u32 av)
{
	struct common_audit_data ad;

	ad.type = LSM_AUDIT_DATA_PATH;
	ad.u.path = file->f_path;
1733
	return inode_has_perm(cred, file_inode(file), av, &ad);
1734 1735
}

L
Linus Torvalds 已提交
1736 1737 1738 1739 1740 1741 1742 1743
/* 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. */
1744 1745 1746
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1747 1748
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1749
	struct inode *inode = file_inode(file);
1750
	struct common_audit_data ad;
1751
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1752 1753
	int rc;

1754
	ad.type = LSM_AUDIT_DATA_PATH;
1755
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1756

1757 1758
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1759 1760 1761 1762
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1763
			goto out;
L
Linus Torvalds 已提交
1764 1765 1766
	}

	/* av is zero if only checking access to the descriptor. */
1767
	rc = 0;
L
Linus Torvalds 已提交
1768
	if (av)
1769
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1770

1771 1772
out:
	return rc;
L
Linus Torvalds 已提交
1773 1774
}

1775 1776 1777
/*
 * Determine the label for an inode that might be unioned.
 */
1778
static int selinux_determine_inode_label(struct inode *dir,
1779 1780 1781 1782 1783
					 const struct qstr *name,
					 u16 tclass,
					 u32 *_new_isid)
{
	const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1784
	const struct inode_security_struct *dsec = inode_security(dir);
1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800
	const struct task_security_struct *tsec = current_security();

	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
		*_new_isid = sbsec->mntpoint_sid;
	} else if ((sbsec->flags & SBLABEL_MNT) &&
		   tsec->create_sid) {
		*_new_isid = tsec->create_sid;
	} else {
		return security_transition_sid(tsec->sid, dsec->sid, tclass,
					       name, _new_isid);
	}

	return 0;
}

L
Linus Torvalds 已提交
1801 1802 1803 1804 1805
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1806
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1807 1808
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1809
	u32 sid, newsid;
1810
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1811 1812
	int rc;

1813
	dsec = inode_security(dir);
L
Linus Torvalds 已提交
1814 1815
	sbsec = dir->i_sb->s_security;

1816 1817
	sid = tsec->sid;

1818
	ad.type = LSM_AUDIT_DATA_DENTRY;
1819
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1820

1821
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1822 1823 1824 1825 1826
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1827 1828 1829 1830
	rc = selinux_determine_inode_label(dir, &dentry->d_name, tclass,
					   &newsid);
	if (rc)
		return rc;
L
Linus Torvalds 已提交
1831

1832
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1833 1834 1835 1836 1837 1838 1839 1840
	if (rc)
		return rc;

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

1841 1842 1843 1844
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1845
	u32 sid = task_sid(ctx);
1846

1847
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1848 1849
}

1850 1851 1852
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1853 1854 1855 1856 1857 1858 1859 1860

/* 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;
1861
	struct common_audit_data ad;
1862
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1863 1864 1865
	u32 av;
	int rc;

1866 1867
	dsec = inode_security(dir);
	isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
1868

1869
	ad.type = LSM_AUDIT_DATA_DENTRY;
1870
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1871 1872 1873

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1874
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888
	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
1889 1890
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1891 1892 1893
		return 0;
	}

1894
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1895 1896 1897 1898 1899 1900 1901 1902 1903
	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;
1904
	struct common_audit_data ad;
1905
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1906 1907 1908 1909
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

1910 1911
	old_dsec = inode_security(old_dir);
	old_isec = backing_inode_security(old_dentry);
1912
	old_is_dir = d_is_dir(old_dentry);
1913
	new_dsec = inode_security(new_dir);
L
Linus Torvalds 已提交
1914

1915
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1916

1917
	ad.u.dentry = old_dentry;
1918
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1919 1920 1921
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1922
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1923 1924 1925 1926
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1927
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1928 1929 1930 1931 1932
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1933
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1934
	av = DIR__ADD_NAME | DIR__SEARCH;
1935
	if (d_is_positive(new_dentry))
L
Linus Torvalds 已提交
1936
		av |= DIR__REMOVE_NAME;
1937
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1938 1939
	if (rc)
		return rc;
1940
	if (d_is_positive(new_dentry)) {
1941
		new_isec = backing_inode_security(new_dentry);
1942
		new_is_dir = d_is_dir(new_dentry);
1943
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953
				  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. */
1954
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1955 1956
			       struct super_block *sb,
			       u32 perms,
1957
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1958 1959
{
	struct superblock_security_struct *sbsec;
1960
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1961 1962

	sbsec = sb->s_security;
1963
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1964 1965 1966 1967 1968 1969 1970
}

/* 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;

A
Al Viro 已提交
1971
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993
		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;
}

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
/* 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
2017
/*
2018
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
2019 2020
 * open permission.
 */
2021
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
2022
{
2023
	u32 av = file_to_av(file);
E
Eric Paris 已提交
2024

2025 2026 2027
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
2028 2029 2030
	return av;
}

L
Linus Torvalds 已提交
2031 2032
/* Hook functions begin here. */

2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076
static int selinux_binder_set_context_mgr(struct task_struct *mgr)
{
	u32 mysid = current_sid();
	u32 mgrsid = task_sid(mgr);

	return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
			    BINDER__SET_CONTEXT_MGR, NULL);
}

static int selinux_binder_transaction(struct task_struct *from,
				      struct task_struct *to)
{
	u32 mysid = current_sid();
	u32 fromsid = task_sid(from);
	u32 tosid = task_sid(to);
	int rc;

	if (mysid != fromsid) {
		rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
				  BINDER__IMPERSONATE, NULL);
		if (rc)
			return rc;
	}

	return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
			    NULL);
}

static int selinux_binder_transfer_binder(struct task_struct *from,
					  struct task_struct *to)
{
	u32 fromsid = task_sid(from);
	u32 tosid = task_sid(to);

	return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
			    NULL);
}

static int selinux_binder_transfer_file(struct task_struct *from,
					struct task_struct *to,
					struct file *file)
{
	u32 sid = task_sid(to);
	struct file_security_struct *fsec = file->f_security;
2077 2078
	struct dentry *dentry = file->f_path.dentry;
	struct inode_security_struct *isec = backing_inode_security(dentry);
2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093
	struct common_audit_data ad;
	int rc;

	ad.type = LSM_AUDIT_DATA_PATH;
	ad.u.path = file->f_path;

	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
			return rc;
	}

2094
	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2095 2096 2097 2098 2099 2100
		return 0;

	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
			    &ad);
}

2101
static int selinux_ptrace_access_check(struct task_struct *child,
2102
				     unsigned int mode)
L
Linus Torvalds 已提交
2103
{
2104
	if (mode & PTRACE_MODE_READ) {
2105 2106 2107
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2108 2109
	}

2110
	return current_has_perm(child, PROCESS__PTRACE);
2111 2112 2113 2114 2115
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
2116 2117 2118
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2119
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
2120
{
C
Casey Schaufler 已提交
2121
	return current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
2122 2123
}

D
David Howells 已提交
2124 2125 2126 2127
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
2128
{
D
David Howells 已提交
2129
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
2130 2131
}

2132 2133 2134 2135 2136 2137 2138 2139 2140 2141
/*
 * (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.
 */

2142 2143
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
2144
{
2145
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
2146 2147 2148 2149
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2150
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2151 2152 2153 2154 2155 2156
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2157 2158 2159 2160 2161
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2162
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2163 2164 2165 2166
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2167
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2168 2169 2170 2171
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2172 2173 2174 2175 2176 2177
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2178 2179
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2180
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2181 2182
}

2183
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2184 2185 2186 2187
{
	int rc;

	switch (type) {
2188 2189
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2190 2191
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2192 2193 2194 2195
	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
	/* Set level of messages printed to console */
	case SYSLOG_ACTION_CONSOLE_LEVEL:
2196 2197
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2198 2199 2200 2201 2202
	case SYSLOG_ACTION_CLOSE:	/* Close log */
	case SYSLOG_ACTION_OPEN:	/* Open log */
	case SYSLOG_ACTION_READ:	/* Read from log */
	case SYSLOG_ACTION_READ_CLEAR:	/* Read/clear last kernel messages */
	case SYSLOG_ACTION_CLEAR:	/* Clear ring buffer */
2203 2204 2205
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217
	}
	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.
 */
2218
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2219 2220 2221
{
	int rc, cap_sys_admin = 0;

C
Casey Schaufler 已提交
2222 2223
	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
					SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2224 2225 2226
	if (rc == 0)
		cap_sys_admin = 1;

C
Casey Schaufler 已提交
2227
	return cap_sys_admin;
L
Linus Torvalds 已提交
2228 2229 2230 2231
}

/* binprm security operations */

2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266
static int check_nnp_nosuid(const struct linux_binprm *bprm,
			    const struct task_security_struct *old_tsec,
			    const struct task_security_struct *new_tsec)
{
	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
	int nosuid = (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID);
	int rc;

	if (!nnp && !nosuid)
		return 0; /* neither NNP nor nosuid */

	if (new_tsec->sid == old_tsec->sid)
		return 0; /* No change in credentials */

	/*
	 * The only transitions we permit under NNP or nosuid
	 * are transitions to bounded SIDs, i.e. SIDs that are
	 * guaranteed to only be allowed a subset of the permissions
	 * of the current SID.
	 */
	rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
	if (rc) {
		/*
		 * On failure, preserve the errno values for NNP vs nosuid.
		 * NNP:  Operation not permitted for caller.
		 * nosuid:  Permission denied to file.
		 */
		if (nnp)
			return -EPERM;
		else
			return -EACCES;
	}
	return 0;
}

2267
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2268
{
2269 2270
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2271
	struct inode_security_struct *isec;
2272
	struct common_audit_data ad;
A
Al Viro 已提交
2273
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2274 2275
	int rc;

2276 2277 2278
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2279 2280
		return 0;

2281 2282
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
2283
	isec = inode_security(inode);
L
Linus Torvalds 已提交
2284 2285

	/* Default to the current task SID. */
2286 2287
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2288

2289
	/* Reset fs, key, and sock SIDs on execve. */
2290 2291 2292
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2293

2294 2295
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2296
		/* Reset exec SID on execve. */
2297
		new_tsec->exec_sid = 0;
2298

2299 2300 2301 2302
		/* Fail on NNP or nosuid if not an allowed transition. */
		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
		if (rc)
			return rc;
L
Linus Torvalds 已提交
2303 2304
	} else {
		/* Check for a default transition on this program. */
2305
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2306 2307
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2308 2309
		if (rc)
			return rc;
2310 2311 2312 2313 2314 2315 2316 2317

		/*
		 * Fallback to old SID on NNP or nosuid if not an allowed
		 * transition.
		 */
		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
		if (rc)
			new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2318 2319
	}

2320
	ad.type = LSM_AUDIT_DATA_PATH;
2321
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2322

2323 2324
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2325 2326 2327 2328 2329
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2330
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2331 2332 2333 2334
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2335
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2336 2337 2338 2339
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357
		/* 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();
2358
			tracer = ptrace_parent(current);
2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372
			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
2373

2374 2375
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2376 2377 2378 2379 2380
	}

	return 0;
}

2381
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2382
{
2383
	const struct task_security_struct *tsec = current_security();
2384
	u32 sid, osid;
L
Linus Torvalds 已提交
2385 2386
	int atsecure = 0;

2387 2388 2389 2390
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2391 2392 2393
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2394
		atsecure = avc_has_perm(osid, sid,
2395 2396
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2397 2398
	}

C
Casey Schaufler 已提交
2399
	return !!atsecure;
L
Linus Torvalds 已提交
2400 2401
}

A
Al Viro 已提交
2402 2403 2404 2405 2406
static int match_file(const void *p, struct file *file, unsigned fd)
{
	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
}

L
Linus Torvalds 已提交
2407
/* Derived from fs/exec.c:flush_old_files. */
2408 2409
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2410 2411
{
	struct file *file, *devnull = NULL;
2412
	struct tty_struct *tty;
2413
	int drop_tty = 0;
A
Al Viro 已提交
2414
	unsigned n;
L
Linus Torvalds 已提交
2415

2416
	tty = get_current_tty();
L
Linus Torvalds 已提交
2417
	if (tty) {
P
Peter Hurley 已提交
2418
		spin_lock(&tty->files_lock);
2419
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2420
			struct tty_file_private *file_priv;
2421

L
Linus Torvalds 已提交
2422
			/* Revalidate access to controlling tty.
2423 2424 2425 2426
			   Use file_path_has_perm on the tty path 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. */
N
Nick Piggin 已提交
2427 2428 2429
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2430
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2431
				drop_tty = 1;
L
Linus Torvalds 已提交
2432
		}
P
Peter Hurley 已提交
2433
		spin_unlock(&tty->files_lock);
A
Alan Cox 已提交
2434
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2435
	}
2436 2437 2438
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2439 2440

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2441 2442 2443
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2444

A
Al Viro 已提交
2445
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2446 2447 2448 2449 2450 2451 2452
	if (IS_ERR(devnull))
		devnull = NULL;
	/* replace all the matching ones with this */
	do {
		replace_fd(n - 1, devnull, 0);
	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
	if (devnull)
A
Al Viro 已提交
2453
		fput(devnull);
L
Linus Torvalds 已提交
2454 2455
}

2456 2457 2458 2459
/*
 * 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
2460
{
2461 2462 2463
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2464

2465 2466 2467
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2468

2469 2470
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2471

2472 2473
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2474

2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487
	/* 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) {
2488 2489
		/* protect against do_prlimit() */
		task_lock(current);
2490 2491 2492 2493
		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
2494
		}
2495 2496
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2497 2498 2499 2500
	}
}

/*
2501 2502
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2503
 */
2504
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2505
{
2506
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2507
	struct itimerval itimer;
2508
	u32 osid, sid;
L
Linus Torvalds 已提交
2509 2510
	int rc, i;

2511 2512 2513 2514
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2515 2516
		return;

2517 2518 2519 2520 2521 2522 2523 2524
	/* 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
2525 2526 2527 2528 2529
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2530 2531 2532
		if (!fatal_signal_pending(current)) {
			flush_sigqueue(&current->pending);
			flush_sigqueue(&current->signal->shared_pending);
2533 2534
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
2535
			recalc_sigpending();
2536
		}
L
Linus Torvalds 已提交
2537 2538 2539
		spin_unlock_irq(&current->sighand->siglock);
	}

2540 2541
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2542
	read_lock(&tasklist_lock);
2543
	__wake_up_parent(current, current->real_parent);
2544
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568
}

/* 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)
{
2569 2570 2571
	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) ||
2572 2573
		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
2574 2575 2576 2577 2578 2579 2580
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2581
	} else
L
Linus Torvalds 已提交
2582 2583 2584 2585 2586
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2587 2588
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2589 2590 2591 2592 2593 2594
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2595
	} else
2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607
		*first = 0;

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

2608
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2609 2610 2611 2612
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2613
	int open_quote = 0;
L
Linus Torvalds 已提交
2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628

	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 {
2629 2630 2631 2632
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2633 2634 2635
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2636
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2637 2638 2639 2640 2641 2642 2643
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2644
	strcpy(in_save, nosec_save);
2645
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2646 2647 2648 2649
out:
	return rc;
}

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 2681 2682 2683
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

	if (!(sbsec->flags & SE_SBINITIALIZED))
		return 0;

	if (!data)
		return 0;

	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
		return 0;

	security_init_mnt_opts(&opts);
	secdata = alloc_secdata();
	if (!secdata)
		return -ENOMEM;
	rc = selinux_sb_copy_data(data, secdata);
	if (rc)
		goto out_free_secdata;

	rc = selinux_parse_opts_str(secdata, &opts);
	if (rc)
		goto out_free_secdata;

	mount_options = opts.mnt_opts;
	flags = opts.mnt_opts_flags;

	for (i = 0; i < opts.num_mnt_opts; i++) {
		u32 sid;

2684
		if (flags[i] == SBLABEL_MNT)
2685
			continue;
2686
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2687
		if (rc) {
2688
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2689 2690
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704
			goto out_free_opts;
		}
		rc = -EINVAL;
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
				goto out_bad_option;
			break;
		case CONTEXT_MNT:
			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
				goto out_bad_option;
			break;
		case ROOTCONTEXT_MNT: {
			struct inode_security_struct *root_isec;
2705
			root_isec = backing_inode_security(sb->s_root);
2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
				goto out_bad_option;
			break;
		}
		case DEFCONTEXT_MNT:
			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
				goto out_bad_option;
			break;
		default:
			goto out_free_opts;
		}
	}

	rc = 0;
out_free_opts:
	security_free_mnt_opts(&opts);
out_free_secdata:
	free_secdata(secdata);
	return rc;
out_bad_option:
	printk(KERN_WARNING "SELinux: unable to change security options "
2728 2729
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2730 2731 2732
	goto out_free_opts;
}

2733
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2734
{
2735
	const struct cred *cred = current_cred();
2736
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2737 2738 2739 2740 2741 2742
	int rc;

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

2743 2744 2745 2746
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2747
	ad.type = LSM_AUDIT_DATA_DENTRY;
2748
	ad.u.dentry = sb->s_root;
2749
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2750 2751
}

2752
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2753
{
2754
	const struct cred *cred = current_cred();
2755
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2756

2757
	ad.type = LSM_AUDIT_DATA_DENTRY;
2758
	ad.u.dentry = dentry->d_sb->s_root;
2759
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2760 2761
}

A
Al Viro 已提交
2762
static int selinux_mount(const char *dev_name,
2763
			 struct path *path,
A
Al Viro 已提交
2764
			 const char *type,
2765 2766
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2767
{
2768
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2769 2770

	if (flags & MS_REMOUNT)
2771
		return superblock_has_perm(cred, path->dentry->d_sb,
2772
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2773
	else
E
Eric Paris 已提交
2774
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2775 2776 2777 2778
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2779
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2780

2781
	return superblock_has_perm(cred, mnt->mnt_sb,
2782
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796
}

/* 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);
}

2797 2798 2799 2800 2801 2802 2803
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
					struct qstr *name, void **ctx,
					u32 *ctxlen)
{
	u32 newsid;
	int rc;

2804 2805 2806 2807 2808
	rc = selinux_determine_inode_label(d_inode(dentry->d_parent), name,
					   inode_mode_to_security_class(mode),
					   &newsid);
	if (rc)
		return rc;
2809 2810 2811 2812

	return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}

2813
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2814 2815
				       const struct qstr *qstr,
				       const char **name,
2816
				       void **value, size_t *len)
2817
{
2818
	const struct task_security_struct *tsec = current_security();
2819
	struct superblock_security_struct *sbsec;
2820
	u32 sid, newsid, clen;
2821
	int rc;
2822
	char *context;
2823 2824 2825

	sbsec = dir->i_sb->s_security;

2826 2827 2828
	sid = tsec->sid;
	newsid = tsec->create_sid;

2829 2830 2831 2832 2833 2834
	rc = selinux_determine_inode_label(
		dir, qstr,
		inode_mode_to_security_class(inode->i_mode),
		&newsid);
	if (rc)
		return rc;
2835

2836
	/* Possibly defer initialization to selinux_complete_init. */
2837
	if (sbsec->flags & SE_SBINITIALIZED) {
2838 2839 2840
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
2841
		isec->initialized = LABEL_INITIALIZED;
2842
	}
2843

2844
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2845 2846
		return -EOPNOTSUPP;

2847 2848
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2849

2850
	if (value && len) {
2851
		rc = security_sid_to_context_force(newsid, &context, &clen);
2852
		if (rc)
2853 2854 2855
			return rc;
		*value = context;
		*len = clen;
2856 2857 2858 2859 2860
	}

	return 0;
}

A
Al Viro 已提交
2861
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880
{
	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);
}

2881
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2882 2883 2884 2885 2886 2887 2888 2889 2890
{
	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);
}

A
Al Viro 已提交
2891
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2892 2893 2894 2895 2896
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2897
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2898 2899 2900 2901 2902 2903
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2904 2905
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2906
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2907 2908
}

2909 2910
static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
				     bool rcu)
L
Linus Torvalds 已提交
2911
{
2912
	const struct cred *cred = current_cred();
2913 2914 2915
	struct common_audit_data ad;
	struct inode_security_struct *isec;
	u32 sid;
L
Linus Torvalds 已提交
2916

2917 2918 2919 2920 2921
	validate_creds(cred);

	ad.type = LSM_AUDIT_DATA_DENTRY;
	ad.u.dentry = dentry;
	sid = cred_sid(cred);
2922 2923 2924
	isec = inode_security_rcu(inode, rcu);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
2925 2926 2927

	return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
				  rcu ? MAY_NOT_BLOCK : 0);
L
Linus Torvalds 已提交
2928 2929
}

2930 2931
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
2932
					   int result,
2933
					   unsigned flags)
L
Linus Torvalds 已提交
2934
{
2935
	struct common_audit_data ad;
2936 2937 2938
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2939
	ad.type = LSM_AUDIT_DATA_INODE;
2940 2941 2942
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2943
			    audited, denied, result, &ad, flags);
2944 2945 2946 2947 2948
	if (rc)
		return rc;
	return 0;
}

2949
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2950
{
2951
	const struct cred *cred = current_cred();
2952 2953
	u32 perms;
	bool from_access;
2954
	unsigned flags = mask & MAY_NOT_BLOCK;
2955 2956 2957 2958 2959
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2960

2961
	from_access = mask & MAY_ACCESS;
2962 2963
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2964 2965
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2966 2967
		return 0;

2968
	validate_creds(cred);
2969

2970 2971
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2972 2973 2974

	perms = file_mask_to_av(inode->i_mode, mask);

2975
	sid = cred_sid(cred);
2976 2977 2978
	isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
2979 2980 2981 2982 2983 2984 2985 2986

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
	audited = avc_audit_required(perms, &avd, rc,
				     from_access ? FILE__AUDIT_ACCESS : 0,
				     &denied);
	if (likely(!audited))
		return rc;

2987
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2988 2989 2990
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2991 2992 2993 2994
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2995
	const struct cred *cred = current_cred();
2996
	unsigned int ia_valid = iattr->ia_valid;
2997
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2998

2999 3000 3001 3002 3003 3004 3005
	/* 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
3006

3007 3008
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
3009
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
3010

3011 3012
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
			&& !(ia_valid & ATTR_FILE))
3013 3014 3015
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
3016 3017
}

3018
static int selinux_inode_getattr(const struct path *path)
L
Linus Torvalds 已提交
3019
{
3020
	return path_has_perm(current_cred(), path, FILE__GETATTR);
L
Linus Torvalds 已提交
3021 3022
}

3023
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3024
{
3025 3026
	const struct cred *cred = current_cred();

3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040
	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. */
E
Eric Paris 已提交
3041
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
3042 3043
}

3044 3045
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
3046
{
3047
	struct inode *inode = d_backing_inode(dentry);
3048
	struct inode_security_struct *isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
3049
	struct superblock_security_struct *sbsec;
3050
	struct common_audit_data ad;
3051
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
3052 3053
	int rc = 0;

3054 3055
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3056 3057

	sbsec = inode->i_sb->s_security;
3058
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
3059 3060
		return -EOPNOTSUPP;

3061
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
3062 3063
		return -EPERM;

3064
	ad.type = LSM_AUDIT_DATA_DENTRY;
3065
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
3066

3067
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
3068 3069 3070 3071
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

3072
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3073
	if (rc == -EINVAL) {
3074 3075 3076 3077 3078 3079 3080
		if (!capable(CAP_MAC_ADMIN)) {
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
3081 3082 3083 3084 3085 3086 3087 3088 3089 3090
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
3091 3092 3093 3094 3095
			ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
			audit_log_format(ab, "op=setxattr invalid_context=");
			audit_log_n_untrustedstring(ab, value, audit_size);
			audit_log_end(ab);

3096
			return rc;
3097
		}
3098 3099
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
3100 3101 3102
	if (rc)
		return rc;

3103
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
3104 3105 3106 3107
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

3108
	rc = security_validate_transition(isec->sid, newsid, sid,
3109
					  isec->sclass);
L
Linus Torvalds 已提交
3110 3111 3112 3113 3114 3115 3116 3117 3118 3119
	if (rc)
		return rc;

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

3120
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3121
					const void *value, size_t size,
3122
					int flags)
L
Linus Torvalds 已提交
3123
{
3124
	struct inode *inode = d_backing_inode(dentry);
3125
	struct inode_security_struct *isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
3126 3127 3128 3129 3130 3131 3132 3133
	u32 newsid;
	int rc;

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

3134
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
3135
	if (rc) {
3136 3137 3138
		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
3139 3140 3141
		return;
	}

3142
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3143
	isec->sid = newsid;
3144
	isec->initialized = LABEL_INITIALIZED;
3145

L
Linus Torvalds 已提交
3146 3147 3148
	return;
}

3149
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3150
{
3151 3152
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3153
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3154 3155
}

3156
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3157
{
3158 3159
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3160
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3161 3162
}

3163
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3164
{
3165 3166
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3167 3168 3169 3170 3171 3172

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

3173
/*
3174
 * Copy the inode security context value to the user.
3175 3176 3177
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3178
static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3179
{
3180 3181 3182
	u32 size;
	int error;
	char *context = NULL;
3183
	struct inode_security_struct *isec = inode_security(inode);
3184

3185 3186
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3187

3188 3189 3190 3191 3192 3193 3194 3195 3196
	/*
	 * 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.
	 */
C
Casey Schaufler 已提交
3197 3198 3199 3200 3201
	error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
			    SECURITY_CAP_NOAUDIT);
	if (!error)
		error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
					    SECURITY_CAP_NOAUDIT);
3202 3203 3204 3205 3206
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3207 3208 3209 3210 3211 3212 3213 3214 3215 3216
	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
3217 3218 3219
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3220
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3221
{
3222
	struct inode_security_struct *isec = inode_security(inode);
L
Linus Torvalds 已提交
3223 3224 3225 3226 3227 3228 3229 3230 3231
	u32 newsid;
	int rc;

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

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

3232
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3233 3234 3235
	if (rc)
		return rc;

3236
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3237
	isec->sid = newsid;
3238
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249
	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;
}

3250
static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3251
{
3252
	struct inode_security_struct *isec = inode_security_novalidate(inode);
3253 3254 3255
	*secid = isec->sid;
}

L
Linus Torvalds 已提交
3256 3257
/* file security operations */

3258
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3259
{
3260
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3261
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3262 3263 3264 3265 3266

	/* 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;

3267 3268
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3269 3270
}

3271 3272
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3273
	struct inode *inode = file_inode(file);
3274
	struct file_security_struct *fsec = file->f_security;
3275
	struct inode_security_struct *isec;
3276 3277
	u32 sid = current_sid();

3278
	if (!mask)
3279 3280 3281
		/* No permission to check.  Existence test. */
		return 0;

3282
	isec = inode_security(inode);
3283 3284
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3285
		/* No change since file_open check. */
3286 3287
		return 0;

3288 3289 3290
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3291 3292 3293 3294 3295 3296 3297 3298 3299 3300
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);
}

3301 3302 3303 3304
/*
 * Check whether a task has the ioctl permission and cmd
 * operation to an inode.
 */
3305
static int ioctl_has_perm(const struct cred *cred, struct file *file,
3306 3307 3308 3309 3310
		u32 requested, u16 cmd)
{
	struct common_audit_data ad;
	struct file_security_struct *fsec = file->f_security;
	struct inode *inode = file_inode(file);
3311
	struct inode_security_struct *isec = inode_security(inode);
3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340
	struct lsm_ioctlop_audit ioctl;
	u32 ssid = cred_sid(cred);
	int rc;
	u8 driver = cmd >> 8;
	u8 xperm = cmd & 0xff;

	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
	ad.u.op = &ioctl;
	ad.u.op->cmd = cmd;
	ad.u.op->path = file->f_path;

	if (ssid != fsec->sid) {
		rc = avc_has_perm(ssid, fsec->sid,
				SECCLASS_FD,
				FD__USE,
				&ad);
		if (rc)
			goto out;
	}

	if (unlikely(IS_PRIVATE(inode)))
		return 0;

	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
			requested, driver, xperm, &ad);
out:
	return rc;
}

L
Linus Torvalds 已提交
3341 3342 3343
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3344
	const struct cred *cred = current_cred();
3345
	int error = 0;
L
Linus Torvalds 已提交
3346

3347 3348 3349 3350 3351 3352 3353
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3354
	case FS_IOC_GETFLAGS:
3355
	/* fall through */
3356
	case FS_IOC_GETVERSION:
3357 3358
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3359

3360
	case FS_IOC_SETFLAGS:
3361
	/* fall through */
3362
	case FS_IOC_SETVERSION:
3363 3364 3365 3366 3367 3368 3369 3370 3371
		error = file_has_perm(cred, file, FILE__SETATTR);
		break;

	/* sys_ioctl() checks */
	case FIONBIO:
	/* fall through */
	case FIOASYNC:
		error = file_has_perm(cred, file, 0);
		break;
L
Linus Torvalds 已提交
3372

3373 3374
	case KDSKBENT:
	case KDSKBSENT:
3375 3376
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3377 3378 3379 3380 3381 3382
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
3383
		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3384 3385
	}
	return error;
L
Linus Torvalds 已提交
3386 3387
}

3388 3389
static int default_noexec;

L
Linus Torvalds 已提交
3390 3391
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3392
	const struct cred *cred = current_cred();
D
David Howells 已提交
3393
	int rc = 0;
3394

3395
	if (default_noexec &&
3396 3397
	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
				   (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3398 3399 3400 3401 3402
		/*
		 * 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
3403
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3404
		if (rc)
D
David Howells 已提交
3405
			goto error;
L
Linus Torvalds 已提交
3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418
	}

	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;

3419
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3420
	}
D
David Howells 已提交
3421 3422 3423

error:
	return rc;
L
Linus Torvalds 已提交
3424 3425
}

3426
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3427
{
C
Casey Schaufler 已提交
3428
	int rc = 0;
L
Linus Torvalds 已提交
3429

3430
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3431
		u32 sid = current_sid();
3432 3433
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3434 3435
	}

3436
	return rc;
3437
}
L
Linus Torvalds 已提交
3438

3439 3440 3441
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452
	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)
{
3453
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3454 3455 3456 3457

	if (selinux_checkreqprot)
		prot = reqprot;

3458 3459
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3460
		int rc = 0;
3461 3462
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3463
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3464 3465 3466
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3467
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3468 3469 3470 3471 3472 3473 3474 3475
		} 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
3476
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3477
		}
3478 3479 3480
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3481 3482 3483 3484 3485 3486

	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)
{
3487 3488 3489
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3490 3491 3492 3493 3494
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3495
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3496 3497 3498
	int err = 0;

	switch (cmd) {
3499 3500
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3501
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3502
			break;
3503 3504 3505 3506 3507 3508 3509
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3510
	case F_GETOWNER_UIDS:
3511
		/* Just check FD__USE permission */
3512
		err = file_has_perm(cred, file, 0);
3513 3514 3515 3516
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3517 3518 3519
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3520
#if BITS_PER_LONG == 32
3521 3522 3523
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3524
#endif
3525
		err = file_has_perm(cred, file, FILE__LOCK);
3526
		break;
L
Linus Torvalds 已提交
3527 3528 3529 3530 3531
	}

	return err;
}

3532
static void selinux_file_set_fowner(struct file *file)
L
Linus Torvalds 已提交
3533 3534 3535 3536
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3537
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3538 3539 3540 3541 3542
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3543
	struct file *file;
3544
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3545 3546 3547 3548
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3549
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3550 3551 3552 3553 3554 3555 3556 3557

	fsec = file->f_security;

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

3558
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3559 3560 3561 3562 3563
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3564 3565 3566
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3567 3568
}

3569
static int selinux_file_open(struct file *file, const struct cred *cred)
3570 3571 3572
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3573

3574
	fsec = file->f_security;
3575
	isec = inode_security(file_inode(file));
3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592
	/*
	 * 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.
	 */
3593
	return file_path_has_perm(cred, file, open_file_to_av(file));
3594 3595
}

L
Linus Torvalds 已提交
3596 3597 3598 3599
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3600
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3601 3602
}

3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617
/*
 * allocate the SELinux part of blank credentials
 */
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
	struct task_security_struct *tsec;

	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;

	cred->security = tsec;
	return 0;
}

D
David Howells 已提交
3618 3619 3620 3621
/*
 * 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
3622
{
D
David Howells 已提交
3623
	struct task_security_struct *tsec = cred->security;
3624

3625 3626 3627 3628 3629
	/*
	 * cred->security == NULL if security_cred_alloc_blank() or
	 * security_prepare_creds() returned an error.
	 */
	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3630
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3631 3632
	kfree(tsec);
}
L
Linus Torvalds 已提交
3633

D
David Howells 已提交
3634 3635 3636 3637 3638 3639 3640 3641
/*
 * 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
3642

D
David Howells 已提交
3643
	old_tsec = old->security;
L
Linus Torvalds 已提交
3644

D
David Howells 已提交
3645 3646 3647
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3648

D
David Howells 已提交
3649
	new->security = tsec;
L
Linus Torvalds 已提交
3650 3651 3652
	return 0;
}

3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663
/*
 * transfer the SELinux data to a blank set of creds
 */
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
{
	const struct task_security_struct *old_tsec = old->security;
	struct task_security_struct *tsec = new->security;

	*tsec = *old_tsec;
}

3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692
/*
 * 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)
{
3693
	struct inode_security_struct *isec = inode_security(inode);
3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704
	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;
3705
	return ret;
3706 3707
}

3708
static int selinux_kernel_module_request(char *kmod_name)
3709
{
3710 3711 3712 3713 3714
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3715
	ad.type = LSM_AUDIT_DATA_KMOD;
3716 3717 3718 3719
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3720 3721
}

L
Linus Torvalds 已提交
3722 3723
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3724
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3725 3726 3727 3728
}

static int selinux_task_getpgid(struct task_struct *p)
{
3729
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3730 3731 3732 3733
}

static int selinux_task_getsid(struct task_struct *p)
{
3734
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3735 3736
}

3737 3738
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3739
	*secid = task_sid(p);
3740 3741
}

L
Linus Torvalds 已提交
3742 3743
static int selinux_task_setnice(struct task_struct *p, int nice)
{
3744
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3745 3746
}

3747 3748
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3749
	return current_has_perm(p, PROCESS__SETSCHED);
3750 3751
}

3752 3753
static int selinux_task_getioprio(struct task_struct *p)
{
3754
	return current_has_perm(p, PROCESS__GETSCHED);
3755 3756
}

3757 3758
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3759
{
3760
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3761 3762 3763 3764

	/* 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
3765
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3766
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3767
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3768 3769 3770 3771

	return 0;
}

3772
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3773
{
3774
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3775 3776 3777 3778
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3779
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3780 3781
}

3782 3783
static int selinux_task_movememory(struct task_struct *p)
{
3784
	return current_has_perm(p, PROCESS__SETSCHED);
3785 3786
}

3787 3788
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3789 3790 3791 3792 3793 3794 3795 3796
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3797
	if (secid)
3798 3799
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3800
	else
3801
		rc = current_has_perm(p, perm);
3802
	return rc;
L
Linus Torvalds 已提交
3803 3804 3805 3806
}

static int selinux_task_wait(struct task_struct *p)
{
3807
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3808 3809 3810 3811 3812 3813
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3814
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3815

3816
	isec->sid = sid;
3817
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
3818 3819 3820
}

/* Returns error only if unable to parse addresses */
3821
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3822
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3823 3824 3825 3826
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3827
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3828 3829 3830 3831 3832 3833 3834 3835
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3836 3837
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3838 3839
	ret = 0;

3840 3841 3842
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3843
	switch (ih->protocol) {
3844 3845
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3846

3847 3848
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3849 3850 3851 3852 3853 3854

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

3855 3856
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3857
		break;
3858 3859 3860 3861 3862 3863 3864 3865
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3866
		offset += ihlen;
3867
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3868
		if (uh == NULL)
3869
			break;
L
Linus Torvalds 已提交
3870

3871 3872
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3873 3874
		break;
	}
L
Linus Torvalds 已提交
3875

J
James Morris 已提交
3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886
	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;

3887 3888
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3889
		break;
3890
	}
J
James Morris 已提交
3891

3892 3893 3894
	default:
		break;
	}
L
Linus Torvalds 已提交
3895 3896 3897 3898 3899 3900 3901
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3902
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3903
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3904 3905 3906 3907
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3908
	__be16 frag_off;
L
Linus Torvalds 已提交
3909

3910
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3911 3912 3913 3914
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3915 3916
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3917 3918 3919 3920
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3921
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3922 3923 3924
	if (offset < 0)
		goto out;

3925 3926 3927
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3928 3929
	switch (nexthdr) {
	case IPPROTO_TCP: {
3930
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3931 3932 3933 3934 3935

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

3936 3937
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3938 3939 3940 3941 3942 3943 3944 3945 3946 3947
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3948 3949
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3950 3951 3952
		break;
	}

J
James Morris 已提交
3953 3954 3955 3956 3957 3958 3959
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3960 3961
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3962
		break;
3963
	}
J
James Morris 已提交
3964

L
Linus Torvalds 已提交
3965 3966 3967 3968 3969 3970 3971 3972 3973 3974
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3975
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3976
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3977
{
3978 3979
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3980

3981
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3982
	case PF_INET:
3983
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3984 3985
		if (ret)
			goto parse_error;
3986 3987
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3988
		goto okay;
L
Linus Torvalds 已提交
3989 3990 3991

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3992
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3993 3994
		if (ret)
			goto parse_error;
3995 3996
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3997
		goto okay;
L
Linus Torvalds 已提交
3998 3999
#endif	/* IPV6 */
	default:
4000 4001
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
4002 4003
	}

4004 4005 4006 4007
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
4008
	return ret;
4009 4010 4011 4012 4013

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
4014 4015
}

4016
/**
4017
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4018
 * @skb: the packet
4019
 * @family: protocol family
4020
 * @sid: the packet's peer label SID
4021 4022
 *
 * Description:
4023 4024 4025 4026 4027 4028
 * 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.
4029 4030
 *
 */
4031
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4032
{
4033
	int err;
4034 4035
	u32 xfrm_sid;
	u32 nlbl_sid;
4036
	u32 nlbl_type;
4037

4038
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4039 4040 4041 4042 4043
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
4044

4045 4046 4047 4048 4049
	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");
4050
		return -EACCES;
4051
	}
4052 4053

	return 0;
4054 4055
}

4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079
/**
 * selinux_conn_sid - Determine the child socket label for a connection
 * @sk_sid: the parent socket's SID
 * @skb_sid: the packet's SID
 * @conn_sid: the resulting connection SID
 *
 * If @skb_sid is valid then the user:role:type information from @sk_sid is
 * combined with the MLS information from @skb_sid in order to create
 * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
 * of @sk_sid.  Returns zero on success, negative values on failure.
 *
 */
static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
{
	int err = 0;

	if (skb_sid != SECSID_NULL)
		err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
	else
		*conn_sid = sk_sid;

	return err;
}

L
Linus Torvalds 已提交
4080
/* socket security operations */
4081

4082 4083
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
4084
{
4085 4086 4087 4088 4089 4090 4091
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
4092 4093
}

4094
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
4095
{
4096
	struct sk_security_struct *sksec = sk->sk_security;
4097
	struct common_audit_data ad;
4098
	struct lsm_network_audit net = {0,};
4099
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
4100

4101 4102
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
4103

4104
	ad.type = LSM_AUDIT_DATA_NET;
4105 4106
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
4107

4108
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4109 4110 4111 4112 4113
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
4114
	const struct task_security_struct *tsec = current_security();
4115
	u32 newsid;
4116
	u16 secclass;
4117
	int rc;
L
Linus Torvalds 已提交
4118 4119

	if (kern)
4120
		return 0;
4121 4122

	secclass = socket_type_to_security_class(family, type, protocol);
4123 4124 4125 4126
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

4127
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
4128 4129
}

V
Venkat Yekkirala 已提交
4130 4131
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
4132
{
4133
	const struct task_security_struct *tsec = current_security();
4134
	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4135
	struct sk_security_struct *sksec;
4136 4137
	int err = 0;

4138 4139
	isec->sclass = socket_type_to_security_class(family, type, protocol);

4140 4141
	if (kern)
		isec->sid = SECINITSID_KERNEL;
4142 4143 4144 4145 4146
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
4147

4148
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4149

4150 4151 4152
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
4153
		sksec->sclass = isec->sclass;
4154
		err = selinux_netlbl_socket_post_create(sock->sk, family);
4155 4156
	}

V
Venkat Yekkirala 已提交
4157
	return err;
L
Linus Torvalds 已提交
4158 4159 4160 4161 4162 4163 4164 4165
}

/* 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)
{
4166
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
4167 4168 4169
	u16 family;
	int err;

4170
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
4171 4172 4173 4174 4175
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4176 4177
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4178
	 */
4179
	family = sk->sk_family;
L
Linus Torvalds 已提交
4180 4181
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4182
		struct sk_security_struct *sksec = sk->sk_security;
4183
		struct common_audit_data ad;
4184
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4185 4186 4187
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4188
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199

		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;
		}

4200 4201 4202
		if (snum) {
			int low, high;

4203
			inet_get_local_port_range(sock_net(sk), &low, &high);
4204 4205

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
4206 4207
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4208 4209
				if (err)
					goto out;
4210
				ad.type = LSM_AUDIT_DATA_NET;
4211 4212 4213
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4214 4215
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4216 4217 4218 4219
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4220
		}
4221

4222
		switch (sksec->sclass) {
4223
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4224 4225
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4226

4227
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4228 4229
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4230 4231 4232 4233 4234

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4235 4236 4237 4238
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4239

4240
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4241 4242
		if (err)
			goto out;
4243

4244
		ad.type = LSM_AUDIT_DATA_NET;
4245 4246 4247
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4248 4249

		if (family == PF_INET)
4250
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4251
		else
4252
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4253

4254 4255
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4256 4257 4258 4259 4260 4261 4262 4263 4264
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4265
	struct sock *sk = sock->sk;
4266
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4267 4268
	int err;

4269
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4270 4271 4272 4273
	if (err)
		return err;

	/*
J
James Morris 已提交
4274
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4275
	 */
4276 4277
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4278
		struct common_audit_data ad;
4279
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4280 4281 4282
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4283
		u32 sid, perm;
L
Linus Torvalds 已提交
4284 4285 4286

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4287
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4288 4289 4290 4291
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4292
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4293 4294 4295 4296
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4297
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4298 4299 4300
		if (err)
			goto out;

4301
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4302 4303
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4304
		ad.type = LSM_AUDIT_DATA_NET;
4305 4306 4307
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4308
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4309 4310 4311 4312
		if (err)
			goto out;
	}

4313 4314
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4315 4316 4317 4318 4319 4320
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4321
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4322 4323 4324 4325 4326 4327 4328 4329
}

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

4330
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4331 4332 4333
	if (err)
		return err;

4334
	newisec = inode_security_novalidate(SOCK_INODE(newsock));
L
Linus Torvalds 已提交
4335

4336
	isec = inode_security_novalidate(SOCK_INODE(sock));
L
Linus Torvalds 已提交
4337 4338
	newisec->sclass = isec->sclass;
	newisec->sid = isec->sid;
4339
	newisec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4340 4341 4342 4343 4344

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4345
				  int size)
L
Linus Torvalds 已提交
4346
{
4347
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4348 4349 4350 4351 4352
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4353
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4354 4355 4356 4357
}

static int selinux_socket_getsockname(struct socket *sock)
{
4358
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4359 4360 4361 4362
}

static int selinux_socket_getpeername(struct socket *sock)
{
4363
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4364 4365
}

4366
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4367
{
4368 4369
	int err;

4370
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4371 4372 4373 4374
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4375 4376 4377 4378 4379
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4380
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4381 4382 4383 4384
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4385
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4386 4387
}

4388 4389
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4390 4391
					      struct sock *newsk)
{
4392 4393
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4394
	struct sk_security_struct *sksec_new = newsk->sk_security;
4395
	struct common_audit_data ad;
4396
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4397 4398
	int err;

4399
	ad.type = LSM_AUDIT_DATA_NET;
4400 4401
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4402

4403 4404
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4405 4406 4407 4408 4409
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4410 4411 4412 4413 4414
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4415

4416 4417 4418 4419
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4420 4421 4422 4423 4424
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4425 4426
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4427
	struct common_audit_data ad;
4428
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4429

4430
	ad.type = LSM_AUDIT_DATA_NET;
4431 4432
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4433

4434 4435
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4436 4437
}

4438 4439
static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
				    char *addrp, u16 family, u32 peer_sid,
4440
				    struct common_audit_data *ad)
4441 4442 4443 4444 4445
{
	int err;
	u32 if_sid;
	u32 node_sid;

4446
	err = sel_netif_sid(ns, ifindex, &if_sid);
4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460
	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);
}

4461
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4462
				       u16 family)
4463
{
4464
	int err = 0;
4465 4466
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4467
	struct common_audit_data ad;
4468
	struct lsm_network_audit net = {0,};
4469 4470
	char *addrp;

4471
	ad.type = LSM_AUDIT_DATA_NET;
4472 4473 4474
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4475 4476 4477
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4478

4479
	if (selinux_secmark_enabled()) {
4480
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4481
				   PACKET__RECV, &ad);
4482 4483 4484
		if (err)
			return err;
	}
4485

4486 4487 4488 4489
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4490

4491 4492 4493 4494 4495
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4496
	int err;
4497
	struct sk_security_struct *sksec = sk->sk_security;
4498 4499
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4500
	struct common_audit_data ad;
4501
	struct lsm_network_audit net = {0,};
4502
	char *addrp;
4503 4504
	u8 secmark_active;
	u8 peerlbl_active;
4505 4506

	if (family != PF_INET && family != PF_INET6)
4507
		return 0;
4508 4509

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4510
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4511 4512
		family = PF_INET;

4513 4514 4515 4516
	/* 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. */
4517
	if (!selinux_policycap_netpeer)
4518 4519 4520
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4521
	peerlbl_active = selinux_peerlbl_enabled();
4522 4523 4524
	if (!secmark_active && !peerlbl_active)
		return 0;

4525
	ad.type = LSM_AUDIT_DATA_NET;
4526 4527 4528
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4529
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4530
	if (err)
4531
		return err;
4532

4533
	if (peerlbl_active) {
4534 4535 4536
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4537 4538
		if (err)
			return err;
4539 4540
		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
					       addrp, family, peer_sid, &ad);
4541 4542
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4543
			return err;
4544
		}
4545 4546
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4547
		if (err) {
4548
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4549 4550
			return err;
		}
4551 4552
	}

4553
	if (secmark_active) {
4554 4555 4556 4557 4558 4559
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4560
	return err;
L
Linus Torvalds 已提交
4561 4562
}

C
Catherine Zhang 已提交
4563 4564
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4565 4566 4567 4568
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4569
	struct sk_security_struct *sksec = sock->sk->sk_security;
4570
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4571

4572 4573
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4574
		peer_sid = sksec->peer_sid;
4575 4576
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4577

C
Catherine Zhang 已提交
4578
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4579
	if (err)
4580
		return err;
L
Linus Torvalds 已提交
4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596

	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);
	return err;
}

4597
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4598
{
4599
	u32 peer_secid = SECSID_NULL;
4600
	u16 family;
4601
	struct inode_security_struct *isec;
C
Catherine Zhang 已提交
4602

4603 4604 4605 4606 4607
	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)
4608 4609 4610 4611
		family = sock->sk->sk_family;
	else
		goto out;

4612 4613 4614 4615
	if (sock && family == PF_UNIX) {
		isec = inode_security_novalidate(SOCK_INODE(sock));
		peer_secid = isec->sid;
	} else if (skb)
4616
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4617

4618
out:
4619
	*secid = peer_secid;
4620 4621 4622
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4623 4624
}

A
Al Viro 已提交
4625
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4626
{
4627 4628 4629 4630 4631 4632 4633 4634
	struct sk_security_struct *sksec;

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

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
4635
	sksec->sclass = SECCLASS_SOCKET;
4636 4637 4638 4639
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4640 4641 4642 4643
}

static void selinux_sk_free_security(struct sock *sk)
{
4644 4645 4646 4647 4648
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4649 4650
}

4651
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4652
{
4653 4654
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4655

4656 4657 4658
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4659

4660
	selinux_netlbl_sk_security_reset(newsksec);
4661 4662
}

V
Venkat Yekkirala 已提交
4663
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4664
{
4665
	if (!sk)
V
Venkat Yekkirala 已提交
4666
		*secid = SECINITSID_ANY_SOCKET;
4667 4668
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4669

V
Venkat Yekkirala 已提交
4670
		*secid = sksec->sid;
4671
	}
4672 4673
}

4674
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4675
{
4676 4677
	struct inode_security_struct *isec =
		inode_security_novalidate(SOCK_INODE(parent));
4678 4679
	struct sk_security_struct *sksec = sk->sk_security;

4680 4681
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
4682
		isec->sid = sksec->sid;
4683
	sksec->sclass = isec->sclass;
4684 4685
}

4686 4687
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4688 4689 4690
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4691
	u16 family = req->rsk_ops->family;
4692
	u32 connsid;
4693 4694
	u32 peersid;

4695
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4696 4697
	if (err)
		return err;
4698 4699 4700 4701 4702
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4703

4704
	return selinux_netlbl_inet_conn_request(req, family);
4705 4706
}

4707 4708
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4709 4710 4711 4712
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4713
	newsksec->peer_sid = req->peer_secid;
4714 4715 4716 4717
	/* 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. */
4718

P
Paul Moore 已提交
4719 4720
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4721
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4722 4723
}

4724
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4725
{
4726
	u16 family = sk->sk_family;
4727 4728
	struct sk_security_struct *sksec = sk->sk_security;

4729 4730 4731 4732 4733
	/* 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);
4734 4735
}

4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756
static int selinux_secmark_relabel_packet(u32 sid)
{
	const struct task_security_struct *__tsec;
	u32 tsid;

	__tsec = current_security();
	tsid = __tsec->sid;

	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
}

static void selinux_secmark_refcount_inc(void)
{
	atomic_inc(&selinux_secmark_refcount);
}

static void selinux_secmark_refcount_dec(void)
{
	atomic_dec(&selinux_secmark_refcount);
}

4757 4758
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4759
{
4760
	fl->flowi_secid = req->secid;
4761 4762
}

4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780
static int selinux_tun_dev_alloc_security(void **security)
{
	struct tun_security_struct *tunsec;

	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
	if (!tunsec)
		return -ENOMEM;
	tunsec->sid = current_sid();

	*security = tunsec;
	return 0;
}

static void selinux_tun_dev_free_security(void *security)
{
	kfree(security);
}

4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795
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);
}

4796
static int selinux_tun_dev_attach_queue(void *security)
4797
{
4798 4799 4800 4801 4802 4803 4804 4805 4806
	struct tun_security_struct *tunsec = security;

	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
			    TUN_SOCKET__ATTACH_QUEUE, NULL);
}

static int selinux_tun_dev_attach(struct sock *sk, void *security)
{
	struct tun_security_struct *tunsec = security;
4807 4808 4809 4810 4811 4812 4813 4814 4815
	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 */

4816
	sksec->sid = tunsec->sid;
4817
	sksec->sclass = SECCLASS_TUN_SOCKET;
4818 4819

	return 0;
4820 4821
}

4822
static int selinux_tun_dev_open(void *security)
4823
{
4824
	struct tun_security_struct *tunsec = security;
4825 4826 4827
	u32 sid = current_sid();
	int err;

4828
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4829 4830 4831 4832 4833 4834 4835
			   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;
4836
	tunsec->sid = sid;
4837 4838 4839 4840

	return 0;
}

L
Linus Torvalds 已提交
4841 4842 4843 4844 4845
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4846
	struct sk_security_struct *sksec = sk->sk_security;
4847

4848
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4849 4850 4851
		err = -EINVAL;
		goto out;
	}
4852
	nlh = nlmsg_hdr(skb);
4853

4854
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4855 4856
	if (err) {
		if (err == -EINVAL) {
4857 4858 4859
			pr_warn_ratelimited("SELinux: unrecognized netlink"
			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
			       " pig=%d comm=%s\n",
4860
			       sk->sk_protocol, nlh->nlmsg_type,
4861 4862
			       secclass_map[sksec->sclass - 1].name,
			       task_pid_nr(current), current->comm);
4863
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4864 4865 4866 4867 4868 4869 4870 4871 4872
				err = 0;
		}

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

4873
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4874 4875 4876 4877 4878 4879
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4880 4881
static unsigned int selinux_ip_forward(struct sk_buff *skb,
				       const struct net_device *indev,
4882
				       u16 family)
L
Linus Torvalds 已提交
4883
{
4884
	int err;
4885 4886
	char *addrp;
	u32 peer_sid;
4887
	struct common_audit_data ad;
4888
	struct lsm_network_audit net = {0,};
4889
	u8 secmark_active;
4890
	u8 netlbl_active;
4891
	u8 peerlbl_active;
4892

4893 4894
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4895

4896
	secmark_active = selinux_secmark_enabled();
4897
	netlbl_active = netlbl_enabled();
4898
	peerlbl_active = selinux_peerlbl_enabled();
4899 4900
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4901

4902 4903 4904
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4905
	ad.type = LSM_AUDIT_DATA_NET;
4906
	ad.u.net = &net;
4907
	ad.u.net->netif = indev->ifindex;
4908
	ad.u.net->family = family;
4909 4910 4911
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4912
	if (peerlbl_active) {
4913 4914
		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
					       addrp, family, peer_sid, &ad);
4915 4916
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4917
			return NF_DROP;
4918 4919
		}
	}
4920 4921 4922 4923 4924 4925

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

4926 4927 4928 4929 4930 4931 4932 4933
	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;

4934 4935 4936
	return NF_ACCEPT;
}

4937
static unsigned int selinux_ipv4_forward(void *priv,
4938
					 struct sk_buff *skb,
4939
					 const struct nf_hook_state *state)
4940
{
4941
	return selinux_ip_forward(skb, state->in, PF_INET);
4942 4943 4944
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4945
static unsigned int selinux_ipv6_forward(void *priv,
4946
					 struct sk_buff *skb,
4947
					 const struct nf_hook_state *state)
4948
{
4949
	return selinux_ip_forward(skb, state->in, PF_INET6);
4950 4951 4952
}
#endif	/* IPV6 */

4953 4954 4955
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4956
	struct sock *sk;
4957 4958 4959 4960 4961 4962 4963 4964
	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 */
4965 4966 4967 4968
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

4969
		if (sk_listener(sk))
4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983 4984 4985
			/* if the socket is the listening state then this
			 * packet is a SYN-ACK packet which means it needs to
			 * be labeled based on the connection/request_sock and
			 * not the parent socket.  unfortunately, we can't
			 * lookup the request_sock yet as it isn't queued on
			 * the parent socket until after the SYN-ACK is sent.
			 * the "solution" is to simply pass the packet as-is
			 * as any IP option based labeling should be copied
			 * from the initial connection request (in the IP
			 * layer).  it is far from ideal, but until we get a
			 * security label in the packet itself this is the
			 * best we can do. */
			return NF_ACCEPT;

		/* standard practice, label using the parent socket */
		sksec = sk->sk_security;
4986 4987 4988 4989 4990 4991 4992 4993 4994
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4995
static unsigned int selinux_ipv4_output(void *priv,
4996
					struct sk_buff *skb,
4997
					const struct nf_hook_state *state)
4998 4999 5000 5001
{
	return selinux_ip_output(skb, PF_INET);
}

5002 5003
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
5004
						u16 family)
5005
{
5006
	struct sock *sk = skb_to_full_sk(skb);
5007
	struct sk_security_struct *sksec;
5008
	struct common_audit_data ad;
5009
	struct lsm_network_audit net = {0,};
5010 5011
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
5012

5013 5014 5015 5016
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

5017
	ad.type = LSM_AUDIT_DATA_NET;
5018 5019 5020
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5021 5022 5023
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

5024
	if (selinux_secmark_enabled())
5025
		if (avc_has_perm(sksec->sid, skb->secmark,
5026
				 SECCLASS_PACKET, PACKET__SEND, &ad))
5027
			return NF_DROP_ERR(-ECONNREFUSED);
5028

5029 5030
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
5031 5032

	return NF_ACCEPT;
5033 5034
}

5035 5036
static unsigned int selinux_ip_postroute(struct sk_buff *skb,
					 const struct net_device *outdev,
5037
					 u16 family)
5038
{
5039 5040
	u32 secmark_perm;
	u32 peer_sid;
5041
	int ifindex = outdev->ifindex;
5042
	struct sock *sk;
5043
	struct common_audit_data ad;
5044
	struct lsm_network_audit net = {0,};
5045 5046 5047
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
5048

5049 5050 5051 5052
	/* 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. */
5053
	if (!selinux_policycap_netpeer)
5054
		return selinux_ip_postroute_compat(skb, ifindex, family);
5055 5056 5057 5058 5059 5060

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = selinux_peerlbl_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

5061
	sk = skb_to_full_sk(skb);
5062

5063
#ifdef CONFIG_XFRM
5064 5065 5066 5067 5068
	/* 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
5069 5070 5071 5072 5073 5074 5075
	 *       is NULL, in this case go ahead and apply access control.
	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
	 *       TCP listening state we cannot wait until the XFRM processing
	 *       is done as we will miss out on the SA label if we do;
	 *       unfortunately, this means more work, but it is only once per
	 *       connection. */
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5076
	    !(sk && sk_listener(sk)))
5077
		return NF_ACCEPT;
5078
#endif
5079

5080
	if (sk == NULL) {
5081 5082 5083 5084
		/* Without an associated socket the packet is either coming
		 * from the kernel or it is being forwarded; check the packet
		 * to determine which and if the packet is being forwarded
		 * query the packet directly to determine the security label. */
5085 5086
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
5087
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5088
				return NF_DROP;
5089 5090
		} else {
			secmark_perm = PACKET__SEND;
5091
			peer_sid = SECINITSID_KERNEL;
5092
		}
5093
	} else if (sk_listener(sk)) {
5094 5095 5096 5097 5098 5099 5100 5101 5102 5103
		/* Locally generated packet but the associated socket is in the
		 * listening state which means this is a SYN-ACK packet.  In
		 * this particular case the correct security label is assigned
		 * to the connection/request_sock but unfortunately we can't
		 * query the request_sock as it isn't queued on the parent
		 * socket until after the SYN-ACK packet is sent; the only
		 * viable choice is to regenerate the label like we do in
		 * selinux_inet_conn_request().  See also selinux_ip_output()
		 * for similar problems. */
		u32 skb_sid;
5104 5105 5106
		struct sk_security_struct *sksec;

		sksec = sk->sk_security;
5107 5108
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123
		/* At this point, if the returned skb peerlbl is SECSID_NULL
		 * and the packet has been through at least one XFRM
		 * transformation then we must be dealing with the "final"
		 * form of labeled IPsec packet; since we've already applied
		 * all of our access controls on this packet we can safely
		 * pass the packet. */
		if (skb_sid == SECSID_NULL) {
			switch (family) {
			case PF_INET:
				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
				break;
			case PF_INET6:
				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
5124
				break;
5125 5126 5127 5128
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
5129 5130 5131
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
5132
	} else {
5133 5134
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
5135 5136 5137 5138
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
5139

5140
	ad.type = LSM_AUDIT_DATA_NET;
5141 5142 5143
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5144
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5145
		return NF_DROP;
5146

5147 5148 5149
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
5150
			return NF_DROP_ERR(-ECONNREFUSED);
5151 5152 5153 5154 5155

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

5156
		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5157
			return NF_DROP;
5158 5159
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5160
			return NF_DROP_ERR(-ECONNREFUSED);
5161 5162

		if (sel_netnode_sid(addrp, family, &node_sid))
5163
			return NF_DROP;
5164 5165
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
5166
			return NF_DROP_ERR(-ECONNREFUSED);
5167
	}
5168

5169
	return NF_ACCEPT;
L
Linus Torvalds 已提交
5170 5171
}

5172
static unsigned int selinux_ipv4_postroute(void *priv,
5173
					   struct sk_buff *skb,
5174
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5175
{
5176
	return selinux_ip_postroute(skb, state->out, PF_INET);
L
Linus Torvalds 已提交
5177 5178 5179
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5180
static unsigned int selinux_ipv6_postroute(void *priv,
5181
					   struct sk_buff *skb,
5182
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5183
{
5184
	return selinux_ip_postroute(skb, state->out, PF_INET6);
L
Linus Torvalds 已提交
5185 5186 5187 5188 5189 5190 5191
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
5192
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5193 5194 5195 5196 5197 5198 5199
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
5200
	u32 sid;
L
Linus Torvalds 已提交
5201

J
James Morris 已提交
5202
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5203 5204 5205
	if (!isec)
		return -ENOMEM;

5206
	sid = task_sid(task);
L
Linus Torvalds 已提交
5207
	isec->sclass = sclass;
5208
	isec->sid = sid;
L
Linus Torvalds 已提交
5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224
	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
5225
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243
	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,
5244
			u32 perms)
L
Linus Torvalds 已提交
5245 5246
{
	struct ipc_security_struct *isec;
5247
	struct common_audit_data ad;
5248
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5249 5250 5251

	isec = ipc_perms->security;

5252
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5253 5254
	ad.u.ipc_id = ipc_perms->key;

5255
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271
}

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;
5272
	struct common_audit_data ad;
5273
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5274 5275 5276 5277 5278 5279 5280 5281
	int rc;

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

	isec = msq->q_perm.security;

5282
	ad.type = LSM_AUDIT_DATA_IPC;
5283
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5284

5285
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301
			  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;
5302
	struct common_audit_data ad;
5303
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5304 5305 5306

	isec = msq->q_perm.security;

5307
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5308 5309
	ad.u.ipc_id = msq->q_perm.key;

5310
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5311 5312 5313 5314 5315 5316 5317 5318
			    MSGQ__ASSOCIATE, &ad);
}

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

5319
	switch (cmd) {
L
Linus Torvalds 已提交
5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337
	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;
	}

5338
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5339 5340 5341 5342 5343 5344 5345
	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;
5346
	struct common_audit_data ad;
5347
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360
	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
		 */
5361
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5362
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5363 5364 5365 5366
		if (rc)
			return rc;
	}

5367
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5368 5369 5370
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5371
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5372 5373 5374
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5375 5376
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5377 5378
	if (!rc)
		/* Can the message be put in the queue? */
5379 5380
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5381 5382 5383 5384 5385 5386 5387 5388 5389 5390

	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;
5391
	struct common_audit_data ad;
5392
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5393 5394 5395 5396 5397
	int rc;

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

5398
	ad.type = LSM_AUDIT_DATA_IPC;
5399
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5400

5401
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5402 5403
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5404
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5405 5406 5407 5408 5409 5410 5411 5412
				  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;
5413
	struct common_audit_data ad;
5414
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5415 5416 5417 5418 5419 5420 5421 5422
	int rc;

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

	isec = shp->shm_perm.security;

5423
	ad.type = LSM_AUDIT_DATA_IPC;
5424
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5425

5426
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442
			  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;
5443
	struct common_audit_data ad;
5444
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5445 5446 5447

	isec = shp->shm_perm.security;

5448
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5449 5450
	ad.u.ipc_id = shp->shm_perm.key;

5451
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5452 5453 5454 5455 5456 5457 5458 5459 5460
			    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;

5461
	switch (cmd) {
L
Linus Torvalds 已提交
5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483
	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;
	}

5484
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497
	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;

5498
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5499 5500 5501 5502 5503 5504
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5505
	struct common_audit_data ad;
5506
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5507 5508 5509 5510 5511 5512 5513 5514
	int rc;

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

	isec = sma->sem_perm.security;

5515
	ad.type = LSM_AUDIT_DATA_IPC;
5516
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5517

5518
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534
			  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;
5535
	struct common_audit_data ad;
5536
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5537 5538 5539

	isec = sma->sem_perm.security;

5540
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5541 5542
	ad.u.ipc_id = sma->sem_perm.key;

5543
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5544 5545 5546 5547 5548 5549 5550 5551 5552
			    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;

5553
	switch (cmd) {
L
Linus Torvalds 已提交
5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580 5581 5582 5583 5584
	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;
	}

5585
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598
	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;

5599
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614
}

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;

5615
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5616 5617
}

5618 5619 5620 5621 5622 5623
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5624
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5625 5626 5627 5628 5629 5630
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5631
			       char *name, char **value)
L
Linus Torvalds 已提交
5632
{
5633
	const struct task_security_struct *__tsec;
5634
	u32 sid;
L
Linus Torvalds 已提交
5635
	int error;
5636
	unsigned len;
L
Linus Torvalds 已提交
5637 5638

	if (current != p) {
5639
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5640 5641 5642 5643
		if (error)
			return error;
	}

5644 5645
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5646 5647

	if (!strcmp(name, "current"))
5648
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5649
	else if (!strcmp(name, "prev"))
5650
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5651
	else if (!strcmp(name, "exec"))
5652
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5653
	else if (!strcmp(name, "fscreate"))
5654
		sid = __tsec->create_sid;
5655
	else if (!strcmp(name, "keycreate"))
5656
		sid = __tsec->keycreate_sid;
5657
	else if (!strcmp(name, "sockcreate"))
5658
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5659
	else
5660 5661
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5662 5663 5664 5665

	if (!sid)
		return 0;

5666 5667 5668 5669
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5670 5671 5672 5673

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5674 5675 5676 5677 5678 5679
}

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
5680
	struct task_struct *tracer;
D
David Howells 已提交
5681 5682
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697
	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"))
5698
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5699
	else if (!strcmp(name, "fscreate"))
5700
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5701
	else if (!strcmp(name, "keycreate"))
5702
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5703
	else if (!strcmp(name, "sockcreate"))
5704
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5705
	else if (!strcmp(name, "current"))
5706
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717
	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--;
		}
5718
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5719
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734
			if (!capable(CAP_MAC_ADMIN)) {
				struct audit_buffer *ab;
				size_t audit_size;

				/* We strip a nul only if it is at the end, otherwise the
				 * context contains a nul and we should audit that */
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
				ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
				audit_log_format(ab, "op=fscreate invalid_context=");
				audit_log_n_untrustedstring(ab, value, audit_size);
				audit_log_end(ab);

5735
				return error;
5736
			}
5737 5738 5739
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5740 5741 5742 5743
		if (error)
			return error;
	}

D
David Howells 已提交
5744 5745 5746 5747
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5748 5749 5750
	/* 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
5751
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5752 5753
	   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
5754 5755
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5756
		tsec->exec_sid = sid;
D
David Howells 已提交
5757
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5758
		tsec->create_sid = sid;
D
David Howells 已提交
5759
	} else if (!strcmp(name, "keycreate")) {
5760 5761
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5762
			goto abort_change;
5763
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5764
	} else if (!strcmp(name, "sockcreate")) {
5765
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5766 5767
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5768
		if (sid == 0)
D
David Howells 已提交
5769 5770 5771 5772
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5773
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5774 5775 5776
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5777
		}
L
Linus Torvalds 已提交
5778 5779 5780

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5781
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5782
		if (error)
D
David Howells 已提交
5783
			goto abort_change;
L
Linus Torvalds 已提交
5784 5785 5786

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5787
		ptsid = 0;
5788
		rcu_read_lock();
5789
		tracer = ptrace_parent(p);
D
David Howells 已提交
5790 5791
		if (tracer)
			ptsid = task_sid(tracer);
5792
		rcu_read_unlock();
D
David Howells 已提交
5793 5794 5795 5796

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5797
			if (error)
D
David Howells 已提交
5798
				goto abort_change;
L
Linus Torvalds 已提交
5799 5800
		}

D
David Howells 已提交
5801 5802 5803 5804 5805 5806 5807
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5808
	return size;
D
David Howells 已提交
5809 5810 5811 5812

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5813 5814
}

5815 5816 5817 5818 5819
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5820 5821 5822 5823 5824
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5825
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5826
{
5827
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5828 5829
}

5830 5831
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5832
	kfree(secdata);
5833 5834
}

5835 5836 5837 5838 5839 5840 5841 5842 5843
static void selinux_inode_invalidate_secctx(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;

	mutex_lock(&isec->lock);
	isec->initialized = LABEL_INVALID;
	mutex_unlock(&isec->lock);
}

5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869
/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
}

/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
}

static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
	int len = 0;
	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
						ctx, true);
	if (len < 0)
		return len;
	*ctxlen = len;
	return 0;
}
5870 5871
#ifdef CONFIG_KEYS

D
David Howells 已提交
5872
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5873
			     unsigned long flags)
5874
{
D
David Howells 已提交
5875
	const struct task_security_struct *tsec;
5876 5877 5878 5879 5880 5881
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5882 5883 5884
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5885
	else
D
David Howells 已提交
5886
		ksec->sid = tsec->sid;
5887

5888
	k->security = ksec;
5889 5890 5891 5892 5893 5894 5895 5896 5897 5898 5899 5900
	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
5901
				  const struct cred *cred,
5902
				  unsigned perm)
5903 5904 5905
{
	struct key *key;
	struct key_security_struct *ksec;
5906
	u32 sid;
5907 5908 5909 5910 5911 5912 5913

	/* 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
5914
	sid = cred_sid(cred);
5915 5916 5917 5918 5919

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5920 5921
}

5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935
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;
}

5936 5937
#endif

C
Casey Schaufler 已提交
5938
static struct security_hook_list selinux_hooks[] = {
5939 5940 5941 5942 5943 5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961 5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985 5986 5987 5988 5989 5990 5991 5992 5993 5994 5995 5996 5997 5998 5999 6000 6001 6002 6003 6004 6005 6006 6007 6008 6009 6010 6011 6012 6013 6014 6015 6016 6017 6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047 6048 6049 6050 6051 6052 6053 6054 6055 6056 6057 6058 6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074
	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),

	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
	LSM_HOOK_INIT(capget, selinux_capget),
	LSM_HOOK_INIT(capset, selinux_capset),
	LSM_HOOK_INIT(capable, selinux_capable),
	LSM_HOOK_INIT(quotactl, selinux_quotactl),
	LSM_HOOK_INIT(quota_on, selinux_quota_on),
	LSM_HOOK_INIT(syslog, selinux_syslog),
	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),

	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),

	LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
	LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),

	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
	LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
	LSM_HOOK_INIT(sb_mount, selinux_mount),
	LSM_HOOK_INIT(sb_umount, selinux_umount),
	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
	LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),

	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),

	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
	LSM_HOOK_INIT(inode_create, selinux_inode_create),
	LSM_HOOK_INIT(inode_link, selinux_inode_link),
	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),

	LSM_HOOK_INIT(file_permission, selinux_file_permission),
	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
	LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
	LSM_HOOK_INIT(file_lock, selinux_file_lock),
	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
	LSM_HOOK_INIT(file_receive, selinux_file_receive),

	LSM_HOOK_INIT(file_open, selinux_file_open),

	LSM_HOOK_INIT(task_create, selinux_task_create),
	LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
	LSM_HOOK_INIT(cred_free, selinux_cred_free),
	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
	LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
	LSM_HOOK_INIT(task_kill, selinux_task_kill),
	LSM_HOOK_INIT(task_wait, selinux_task_wait),
	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),

	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),

	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
	LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),

	LSM_HOOK_INIT(msg_queue_alloc_security,
			selinux_msg_queue_alloc_security),
	LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),

	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
	LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),

	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
	LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),

	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),

	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),

	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6075
	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6076 6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117
	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),

	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),

	LSM_HOOK_INIT(socket_create, selinux_socket_create),
	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
	LSM_HOOK_INIT(socket_getpeersec_stream,
			selinux_socket_getpeersec_stream),
	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6118 6119

#ifdef CONFIG_SECURITY_NETWORK_XFRM
6120 6121 6122 6123 6124 6125 6126 6127 6128 6129 6130 6131 6132
	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
			selinux_xfrm_state_alloc_acquire),
	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
			selinux_xfrm_state_pol_flow_match),
	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
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#endif
6134 6135

#ifdef CONFIG_KEYS
6136 6137 6138 6139
	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
	LSM_HOOK_INIT(key_free, selinux_key_free),
	LSM_HOOK_INIT(key_permission, selinux_key_permission),
	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6140
#endif
6141 6142

#ifdef CONFIG_AUDIT
6143 6144 6145 6146
	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6147
#endif
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};

static __init int selinux_init(void)
{
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	if (!security_module_enable("selinux")) {
6153 6154 6155 6156
		selinux_enabled = 0;
		return 0;
	}

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	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. */
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	cred_init_security();
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6167 6168
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

6169 6170
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
6171
					    0, SLAB_PANIC, NULL);
6172 6173 6174
	file_security_cache = kmem_cache_create("selinux_file_security",
					    sizeof(struct file_security_struct),
					    0, SLAB_PANIC, NULL);
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	avc_init();

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	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
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6179 6180 6181
	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC netcache callback\n");

6182
	if (selinux_enforcing)
6183
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6184
	else
6185
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6186

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	return 0;
}

6190 6191 6192 6193 6194
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

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void selinux_complete_init(void)
{
6197
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
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	/* Set up any superblocks initialized prior to the policy load. */
6200
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6201
	iterate_supers(delayed_superblock_init, NULL);
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}

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

6208
#if defined(CONFIG_NETFILTER)
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6210
static struct nf_hook_ops selinux_nf_ops[] = {
6211 6212
	{
		.hook =		selinux_ipv4_postroute,
6213
		.pf =		NFPROTO_IPV4,
6214 6215 6216 6217 6218
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
6219
		.pf =		NFPROTO_IPV4,
6220 6221
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6222 6223 6224
	},
	{
		.hook =		selinux_ipv4_output,
6225
		.pf =		NFPROTO_IPV4,
6226 6227
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6228
	},
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6230 6231
	{
		.hook =		selinux_ipv6_postroute,
6232
		.pf =		NFPROTO_IPV6,
6233 6234 6235 6236 6237
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
6238
		.pf =		NFPROTO_IPV6,
6239 6240
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
6241
	},
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#endif	/* IPV6 */
6243
};
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static int __init selinux_nf_ip_init(void)
{
6247
	int err;
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	if (!selinux_enabled)
6250
		return 0;
6251 6252 6253

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

6254
	err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6255
	if (err)
6256
		panic("SELinux: nf_register_hooks: error %d\n", err);
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6258
	return 0;
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}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6266
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
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6268
	nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
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6269 6270 6271
}
#endif

6272
#else /* CONFIG_NETFILTER */
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6278
#endif /* CONFIG_NETFILTER */
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6281 6282
static int selinux_disabled;

L
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int selinux_disable(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;
6298
	selinux_enabled = 0;
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C
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6300
	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
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6302 6303 6304
	/* Try to destroy the avc node cache */
	avc_disable();

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

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif