hooks.c 141.0 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
 *	Paul Moore <paul.moore@hp.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

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

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

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

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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


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

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

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

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

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

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

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

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

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

	return tsec->sid;
}

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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	selinux_netlbl_sk_security_reset(ssec);
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	return 0;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
		sbsec->flags |= SE_SBLABELSUPP;

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

out_free:
571
	security_free_mnt_opts(opts);
572 573
	return rc;
}
L
Linus Torvalds 已提交
574

575 576 577
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
578 579
	char mnt_flags = sbsec->flags & SE_MNTMASK;

580
	/* check if the old mount command had the same options */
581
	if (sbsec->flags & SE_SBINITIALIZED)
582 583 584 585 586 587 588
		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
	 */
589 590
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
591 592 593
			return 1;
	return 0;
}
594

595 596 597 598
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
599 600
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
601
{
602
	const struct cred *cred = current_cred();
603 604 605
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
606 607
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
608 609
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
610 611 612
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
613 614 615 616 617 618 619 620 621 622 623 624 625 626 627

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			spin_lock(&sb_security_lock);
			if (list_empty(&sbsec->list))
				list_add(&sbsec->list, &superblock_security_head);
			spin_unlock(&sb_security_lock);
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
628 629
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
630
		goto out;
631
	}
L
Linus Torvalds 已提交
632

633 634 635 636 637 638 639 640 641 642 643
	/*
	 * 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)
	 */
644
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
645
	    && (num_opts == 0))
646
		goto out;
647

648 649 650 651 652 653 654
	/*
	 * 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;
655 656 657

		if (flags[i] == SE_SBLABELSUPP)
			continue;
658 659
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
660 661 662
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707
			       mount_options[i], sb->s_id, name, rc);
			goto out;
		}
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			fscontext_sid = sid;

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

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

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

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

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

			sbsec->flags |= ROOTCONTEXT_MNT;

			break;
		case DEFCONTEXT_MNT:
			defcontext_sid = sid;

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

			sbsec->flags |= DEFCONTEXT_MNT;

			break;
		default:
			rc = -EINVAL;
			goto out;
L
Linus Torvalds 已提交
708
		}
709 710
	}

711
	if (sbsec->flags & SE_SBINITIALIZED) {
712
		/* previously mounted with options, but not on this attempt? */
713
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
714 715 716 717 718
			goto out_double_mount;
		rc = 0;
		goto out;
	}

719
	if (strcmp(sb->s_type->name, "proc") == 0)
720
		sbsec->flags |= SE_SBPROC;
721 722

	/* Determine the labeling behavior to use for this filesystem type. */
723
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
724 725
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
726
		       __func__, sb->s_type->name, rc);
727 728
		goto out;
	}
L
Linus Torvalds 已提交
729

730 731
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
732
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
733
		if (rc)
734
			goto out;
L
Linus Torvalds 已提交
735

736
		sbsec->sid = fscontext_sid;
737 738 739 740 741 742 743
	}

	/*
	 * 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.
	 */
744 745
	if (context_sid) {
		if (!fscontext_sid) {
746 747
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
748
			if (rc)
749 750
				goto out;
			sbsec->sid = context_sid;
751
		} else {
752 753
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
754
			if (rc)
755
				goto out;
756
		}
757 758
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
759

760
		sbsec->mntpoint_sid = context_sid;
761
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
762 763
	}

764
	if (rootcontext_sid) {
765 766
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
767
		if (rc)
768
			goto out;
769

770 771
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
772 773
	}

774 775 776 777 778 779
	if (defcontext_sid) {
		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
780 781
		}

782 783
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
784
							     sbsec, cred);
785 786 787
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
788

789
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
790 791
	}

792
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
793
out:
794
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
795
	return rc;
796 797 798 799 800
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
	goto out;
L
Linus Torvalds 已提交
801 802
}

803 804
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
805
{
806 807
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
808

809 810 811
	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
812

813 814 815 816 817 818 819 820 821 822 823 824
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
	 * mount options.  thus we can safely put this sb on the list and deal
	 * with it later
	 */
	if (!ss_initialized) {
		spin_lock(&sb_security_lock);
		if (list_empty(&newsbsec->list))
			list_add(&newsbsec->list, &superblock_security_head);
		spin_unlock(&sb_security_lock);
		return;
	}
825 826

	/* how can we clone if the old one wasn't set up?? */
827
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
828

829
	/* if fs is reusing a sb, just let its options stand... */
830
	if (newsbsec->flags & SE_SBINITIALIZED)
831 832
		return;

833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

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

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

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
			struct inode *newinode = newsb->s_root->d_inode;
			struct inode_security_struct *newisec = newinode->i_security;
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
852
	}
853 854 855 856 857
	if (set_rootcontext) {
		const struct inode *oldinode = oldsb->s_root->d_inode;
		const struct inode_security_struct *oldisec = oldinode->i_security;
		struct inode *newinode = newsb->s_root->d_inode;
		struct inode_security_struct *newisec = newinode->i_security;
L
Linus Torvalds 已提交
858

859
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
860 861
	}

862 863 864 865
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

866 867
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
868
{
869
	char *p;
870 871
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
872
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
873

874
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
875

876 877 878 879
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
880

881 882
		if (!*p)
			continue;
L
Linus Torvalds 已提交
883

884
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
885

886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937
		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;
938 939
		case Opt_labelsupport:
			break;
940 941 942 943
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
944 945 946

		}
	}
947

948 949 950 951 952 953 954 955 956 957 958
	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;
	}

959
	if (fscontext) {
960 961
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
962 963
	}
	if (context) {
964 965
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
966 967
	}
	if (rootcontext) {
968 969
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
970 971
	}
	if (defcontext) {
972 973
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
974 975
	}

976 977 978
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

979 980 981 982 983
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
984 985
	return rc;
}
986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012
/*
 * string mount options parsing and call set the sbsec
 */
static int superblock_doinit(struct super_block *sb, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!data)
		goto out;

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

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

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

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1013

A
Adrian Bunk 已提交
1014 1015
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1016 1017 1018 1019 1020
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1021 1022 1023 1024 1025 1026
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040

		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;
1041 1042 1043 1044
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064
		default:
			BUG();
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
		seq_puts(m, opts->mnt_opts[i]);
		if (has_comma)
			seq_putc(m, '\"');
	}
}

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

	rc = selinux_get_mnt_opts(sb, &opts);
1065 1066 1067 1068
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1069
		return rc;
1070
	}
1071 1072 1073 1074 1075 1076 1077 1078

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101
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;
}

1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
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
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
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:
1128 1129 1130 1131
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1132
		case SOCK_DGRAM:
1133 1134 1135 1136
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1137 1138
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1139
		default:
L
Linus Torvalds 已提交
1140 1141 1142 1143 1144 1145 1146 1147 1148
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
		case NETLINK_FIREWALL:
			return SECCLASS_NETLINK_FIREWALL_SOCKET;
1149
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162
			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
		case NETLINK_NFLOG:
			return SECCLASS_NETLINK_NFLOG_SOCKET;
		case NETLINK_XFRM:
			return SECCLASS_NETLINK_XFRM_SOCKET;
		case NETLINK_SELINUX:
			return SECCLASS_NETLINK_SELINUX_SOCKET;
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
		case NETLINK_IP6_FW:
			return SECCLASS_NETLINK_IP6FW_SOCKET;
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1163 1164
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
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		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1172 1173
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
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1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186
	}

	return SECCLASS_SOCKET;
}

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

1187
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234
	if (!buffer)
		return -ENOMEM;

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

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

	if (isec->initialized)
		goto out;

1235
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1236
	if (isec->initialized)
1237
		goto out_unlock;
L
Linus Torvalds 已提交
1238 1239

	sbsec = inode->i_sb->s_security;
1240
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1241 1242 1243 1244 1245 1246 1247
		/* 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);
1248
		goto out_unlock;
L
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1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267
	}

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

		/* Need a dentry, since the xattr API requires one.
		   Life would be simpler if we could just pass the inode. */
		if (opt_dentry) {
			/* Called from d_instantiate or d_splice_alias. */
			dentry = dget(opt_dentry);
		} else {
			/* Called from selinux_complete_init, try to find a dentry. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
1268 1269 1270 1271 1272 1273 1274 1275 1276
			/*
			 * 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.
			 */
1277
			goto out_unlock;
L
Linus Torvalds 已提交
1278 1279 1280
		}

		len = INITCONTEXTLEN;
1281
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1282 1283 1284
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1285
			goto out_unlock;
L
Linus Torvalds 已提交
1286
		}
1287
		context[len] = '\0';
L
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1288 1289 1290
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1291 1292
			kfree(context);

L
Linus Torvalds 已提交
1293 1294 1295 1296 1297
			/* 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);
1298
				goto out_unlock;
L
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1299 1300
			}
			len = rc;
1301
			context = kmalloc(len+1, GFP_NOFS);
L
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1302 1303 1304
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1305
				goto out_unlock;
L
Linus Torvalds 已提交
1306
			}
1307
			context[len] = '\0';
L
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1308 1309 1310 1311 1312 1313 1314
			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
1315
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1316
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1317 1318
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1319
				goto out_unlock;
L
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1320 1321 1322 1323 1324
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1325
			rc = security_context_to_sid_default(context, rc, &sid,
1326 1327
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1328
			if (rc) {
1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341
				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
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1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		isec->sid = sid;
		break;
	case SECURITY_FS_USE_TASK:
		isec->sid = isec->task_sid;
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
		isec->sid = sbsec->sid;

		/* Try to obtain a transition SID. */
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		rc = security_transition_sid(isec->task_sid,
					     sbsec->sid,
					     isec->sclass,
					     &sid);
		if (rc)
1365
			goto out_unlock;
L
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1366 1367
		isec->sid = sid;
		break;
1368 1369 1370
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
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1371
	default:
1372
		/* Default to the fs superblock SID. */
L
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1373 1374
		isec->sid = sbsec->sid;

1375
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
L
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1376 1377 1378 1379 1380 1381 1382
			struct proc_inode *proci = PROC_I(inode);
			if (proci->pde) {
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
				rc = selinux_proc_get_sid(proci->pde,
							  isec->sclass,
							  &sid);
				if (rc)
1383
					goto out_unlock;
L
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1384 1385 1386 1387 1388 1389 1390 1391
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1392 1393
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426
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
1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439
/*
 * 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);
}

1440
/*
1441
 * Check permission between a pair of tasks, e.g. signal checks,
1442 1443
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1444
 * - this uses the default subjective creds of tsk1
1445 1446 1447
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1448 1449
			 u32 perms)
{
1450 1451
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1452

1453 1454 1455 1456 1457
	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
1458 1459
}

1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475
/*
 * 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);
}

1476 1477 1478 1479
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1480 1481
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1482
			       const struct cred *cred,
1483
			       int cap, int audit)
L
Linus Torvalds 已提交
1484
{
1485
	struct common_audit_data ad;
1486
	struct av_decision avd;
1487
	u16 sclass;
1488
	u32 sid = cred_sid(cred);
1489
	u32 av = CAP_TO_MASK(cap);
1490
	int rc;
L
Linus Torvalds 已提交
1491

1492
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
L
Linus Torvalds 已提交
1493 1494 1495
	ad.tsk = tsk;
	ad.u.cap = cap;

1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507
	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();
	}
1508

1509
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1510
	if (audit == SECURITY_CAP_AUDIT)
1511
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1512
	return rc;
L
Linus Torvalds 已提交
1513 1514 1515 1516 1517 1518
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1519
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1520

1521
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1522 1523 1524 1525 1526 1527
			    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). */
1528
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1529 1530
			  struct inode *inode,
			  u32 perms,
1531
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1532 1533
{
	struct inode_security_struct *isec;
1534
	struct common_audit_data ad;
1535
	u32 sid;
L
Linus Torvalds 已提交
1536

1537 1538
	validate_creds(cred);

1539
	if (unlikely(IS_PRIVATE(inode)))
1540 1541
		return 0;

1542
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1543 1544 1545 1546
	isec = inode->i_security;

	if (!adp) {
		adp = &ad;
1547
		COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
1548 1549 1550
		ad.u.fs.inode = inode;
	}

1551
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1552 1553 1554 1555 1556
}

/* 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. */
1557
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1558 1559 1560 1561 1562
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1563
	struct common_audit_data ad;
1564

1565
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1566 1567
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1568
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1569 1570 1571 1572 1573 1574 1575 1576 1577 1578
}

/* 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. */
1579 1580 1581
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1582 1583
{
	struct file_security_struct *fsec = file->f_security;
1584
	struct inode *inode = file->f_path.dentry->d_inode;
1585
	struct common_audit_data ad;
1586
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1587 1588
	int rc;

1589
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1590
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1591

1592 1593
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1594 1595 1596 1597
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1598
			goto out;
L
Linus Torvalds 已提交
1599 1600 1601
	}

	/* av is zero if only checking access to the descriptor. */
1602
	rc = 0;
L
Linus Torvalds 已提交
1603
	if (av)
1604
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1605

1606 1607
out:
	return rc;
L
Linus Torvalds 已提交
1608 1609 1610 1611 1612 1613 1614
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1615 1616
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1617 1618
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1619
	u32 sid, newsid;
1620
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1621 1622 1623 1624 1625
	int rc;

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

1626 1627 1628
	sid = tsec->sid;
	newsid = tsec->create_sid;

1629
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1630
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1631

1632
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1633 1634 1635 1636 1637
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1638
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1639
		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
L
Linus Torvalds 已提交
1640 1641 1642 1643
		if (rc)
			return rc;
	}

1644
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1645 1646 1647 1648 1649 1650 1651 1652
	if (rc)
		return rc;

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

1653 1654 1655 1656
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1657
	u32 sid = task_sid(ctx);
1658

1659
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1660 1661
}

1662 1663 1664
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1665 1666 1667 1668 1669 1670 1671 1672

/* 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;
1673
	struct common_audit_data ad;
1674
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1675 1676 1677 1678 1679 1680
	u32 av;
	int rc;

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

1681
	COMMON_AUDIT_DATA_INIT(&ad, FS);
1682
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1683 1684 1685

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1686
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700
	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
1701 1702
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1703 1704 1705
		return 0;
	}

1706
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1707 1708 1709 1710 1711 1712 1713 1714 1715
	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;
1716
	struct common_audit_data ad;
1717
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1718 1719 1720 1721 1722 1723 1724 1725 1726
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

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

1727
	COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
1728

1729
	ad.u.fs.path.dentry = old_dentry;
1730
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1731 1732 1733
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1734
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1735 1736 1737 1738
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1739
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1745
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1746 1747 1748
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1749
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1750 1751 1752 1753 1754
	if (rc)
		return rc;
	if (new_dentry->d_inode) {
		new_isec = new_dentry->d_inode->i_security;
		new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1755
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1756 1757 1758 1759 1760 1761 1762 1763 1764 1765
				  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. */
1766
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1767 1768
			       struct super_block *sb,
			       u32 perms,
1769
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1770 1771
{
	struct superblock_security_struct *sbsec;
1772
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1773 1774

	sbsec = sb->s_security;
1775
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805
}

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

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

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

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

	return av;
}

1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828
/* 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
1829
/*
1830
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1831 1832
 * open permission.
 */
1833
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1834
{
1835
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1836 1837

	if (selinux_policycap_openperm) {
1838
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851
		/*
		 * lnk files and socks do not really have an 'open'
		 */
		if (S_ISREG(mode))
			av |= FILE__OPEN;
		else if (S_ISCHR(mode))
			av |= CHR_FILE__OPEN;
		else if (S_ISBLK(mode))
			av |= BLK_FILE__OPEN;
		else if (S_ISFIFO(mode))
			av |= FIFO_FILE__OPEN;
		else if (S_ISDIR(mode))
			av |= DIR__OPEN;
E
Eric Paris 已提交
1852 1853
		else if (S_ISSOCK(mode))
			av |= SOCK_FILE__OPEN;
E
Eric Paris 已提交
1854
		else
E
Eric Paris 已提交
1855
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1856
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1857 1858 1859 1860
	}
	return av;
}

L
Linus Torvalds 已提交
1861 1862
/* Hook functions begin here. */

1863
static int selinux_ptrace_access_check(struct task_struct *child,
1864
				     unsigned int mode)
L
Linus Torvalds 已提交
1865 1866 1867
{
	int rc;

1868
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1869 1870 1871
	if (rc)
		return rc;

1872
	if (mode == PTRACE_MODE_READ) {
1873 1874 1875
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1876 1877
	}

1878
	return current_has_perm(child, PROCESS__PTRACE);
1879 1880 1881 1882 1883 1884
}

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

1885
	rc = cap_ptrace_traceme(parent);
1886 1887 1888 1889
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1890 1891 1892
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1893
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1894 1895 1896
{
	int error;

1897
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1898 1899 1900
	if (error)
		return error;

1901
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1902 1903
}

D
David Howells 已提交
1904 1905 1906 1907
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
1908 1909 1910
{
	int error;

1911
	error = cap_capset(new, old,
D
David Howells 已提交
1912
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1913 1914 1915
	if (error)
		return error;

D
David Howells 已提交
1916
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1917 1918
}

1919 1920 1921 1922 1923 1924 1925 1926 1927 1928
/*
 * (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.
 */

1929 1930
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
			   int cap, int audit)
L
Linus Torvalds 已提交
1931 1932 1933
{
	int rc;

1934
	rc = cap_capable(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1935 1936 1937
	if (rc)
		return rc;

1938
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1939 1940
}

1941 1942 1943 1944 1945 1946
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1947
	buffer = (char *)__get_free_page(GFP_KERNEL);
1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
	if (!buffer)
		goto out;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (table) {
		const char *name = table->procname;
		size_t namelen = strlen(name);
		buflen -= namelen + 1;
		if (buflen < 0)
			goto out_free;
		end -= namelen;
		memcpy(end, name, namelen);
		*--end = '/';
		path = end;
		table = table->parent;
	}
1969 1970 1971 1972 1973 1974
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1975 1976 1977 1978 1979 1980 1981
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1982 1983 1984 1985
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1986
	u32 tsid, sid;
L
Linus Torvalds 已提交
1987 1988
	int rc;

1989
	sid = current_sid();
L
Linus Torvalds 已提交
1990

1991 1992
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1993 1994 1995 1996 1997 1998 1999
	if (rc) {
		/* Default to the well-defined sysctl SID. */
		tsid = SECINITSID_SYSCTL;
	}

	/* The op values are "defined" in sysctl.c, thereby creating
	 * a bad coupling between this module and sysctl.c */
2000
	if (op == 001) {
2001
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
2002 2003 2004 2005 2006 2007 2008 2009
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
2010
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
2011
					     SECCLASS_FILE, av, NULL);
2012
	}
L
Linus Torvalds 已提交
2013 2014 2015 2016 2017 2018

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2019
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2020 2021 2022 2023 2024 2025
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2026 2027 2028 2029 2030
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2031
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2032 2033 2034 2035
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2036
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2037 2038 2039 2040
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2041 2042 2043 2044 2045 2046
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2047 2048 2049
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2050 2051 2052 2053 2054 2055
}

static int selinux_syslog(int type)
{
	int rc;

2056
	rc = cap_syslog(type);
L
Linus Torvalds 已提交
2057 2058 2059 2060
	if (rc)
		return rc;

	switch (type) {
2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077
	case 3:		/* Read last kernel messages */
	case 10:	/* Return size of the log buffer */
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
	case 6:		/* Disable logging to console */
	case 7:		/* Enable logging to console */
	case 8:		/* Set level of messages printed to console */
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
	case 0:		/* Close log */
	case 1:		/* Open log */
	case 2:		/* Read from log */
	case 4:		/* Read/clear last kernel messages */
	case 5:		/* Clear ring buffer */
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089
	}
	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.
 */
2090
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2091 2092 2093
{
	int rc, cap_sys_admin = 0;

2094 2095
	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2096 2097 2098
	if (rc == 0)
		cap_sys_admin = 1;

2099
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2100 2101 2102 2103
}

/* binprm security operations */

2104
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2105
{
2106 2107
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2108
	struct inode_security_struct *isec;
2109
	struct common_audit_data ad;
2110
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2111 2112
	int rc;

2113
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2114 2115 2116
	if (rc)
		return rc;

2117 2118 2119
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2120 2121
		return 0;

2122 2123
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2124 2125 2126
	isec = inode->i_security;

	/* Default to the current task SID. */
2127 2128
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2129

2130
	/* Reset fs, key, and sock SIDs on execve. */
2131 2132 2133
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2134

2135 2136
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2137
		/* Reset exec SID on execve. */
2138
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2139 2140
	} else {
		/* Check for a default transition on this program. */
2141 2142
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2143 2144 2145 2146
		if (rc)
			return rc;
	}

2147
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2148
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2149

J
Josef Sipek 已提交
2150
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2151
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2152

2153 2154
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2155 2156 2157 2158 2159
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2160
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2161 2162 2163 2164
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2165
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2166 2167 2168 2169
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
					  SECCLASS_PROCESS, PROCESS__SHARE,
					  NULL);
			if (rc)
				return -EPERM;
		}

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

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

			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2203

2204 2205
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2206 2207 2208 2209 2210
	}

	return 0;
}

2211
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2212
{
2213 2214 2215
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2216 2217
	int atsecure = 0;

2218 2219 2220 2221
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2222 2223 2224
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2225
		atsecure = avc_has_perm(osid, sid,
2226 2227
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2228 2229
	}

2230
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2231 2232 2233 2234 2235 2236
}

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

/* Derived from fs/exec.c:flush_old_files. */
2237 2238
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2239
{
2240
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2241
	struct file *file, *devnull = NULL;
2242
	struct tty_struct *tty;
2243
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2244
	long j = -1;
2245
	int drop_tty = 0;
L
Linus Torvalds 已提交
2246

2247
	tty = get_current_tty();
L
Linus Torvalds 已提交
2248 2249
	if (tty) {
		file_list_lock();
2250 2251 2252
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2253 2254 2255 2256 2257
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
2258 2259
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2260
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2261
					   FILE__READ | FILE__WRITE, NULL)) {
2262
				drop_tty = 1;
L
Linus Torvalds 已提交
2263 2264 2265
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2266
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2267
	}
2268 2269 2270
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2271 2272 2273

	/* Revalidate access to inherited open files. */

2274
	COMMON_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2275 2276 2277 2278 2279 2280 2281 2282

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

		j++;
		i = j * __NFDBITS;
2283
		fdt = files_fdtable(files);
2284
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2285
			break;
2286
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2287 2288 2289
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2290
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2291 2292 2293 2294
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2295
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2307
						get_file(devnull);
L
Linus Torvalds 已提交
2308
					} else {
2309 2310 2311 2312
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2313 2314
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2331 2332 2333 2334
/*
 * 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
2335
{
2336 2337 2338
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2339

2340 2341 2342
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2343

2344 2345
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2346

2347 2348
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2349

2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366
	/* Check whether the new SID can inherit resource limits from the old
	 * SID.  If not, reset all soft limits to the lower of the current
	 * task's hard limit and the init task's soft limit.
	 *
	 * Note that the setting of hard limits (even to lower them) can be
	 * controlled by the setrlimit check.  The inclusion of the init task's
	 * soft limit into the computation is to avoid resetting soft limits
	 * higher than the default soft limit for cases where the default is
	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
	 */
	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
		for (i = 0; i < RLIM_NLIMITS; i++) {
			rlim = current->signal->rlim + i;
			initrlim = init_task.signal->rlim + i;
			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
L
Linus Torvalds 已提交
2367
		}
2368
		update_rlimit_cpu(current->signal->rlim[RLIMIT_CPU].rlim_cur);
L
Linus Torvalds 已提交
2369 2370 2371 2372
	}
}

/*
2373 2374
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2375
 */
2376
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2377
{
2378
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2379
	struct itimerval itimer;
2380
	u32 osid, sid;
L
Linus Torvalds 已提交
2381 2382
	int rc, i;

2383 2384 2385 2386
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2387 2388
		return;

2389 2390 2391 2392 2393 2394 2395 2396
	/* 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
2397 2398 2399 2400 2401
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2402 2403 2404 2405 2406
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2407 2408 2409
		spin_unlock_irq(&current->sighand->siglock);
	}

2410 2411
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2412
	read_lock(&tasklist_lock);
2413
	__wake_up_parent(current, current->real_parent);
2414
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438
}

/* 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)
{
2439 2440 2441
	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) ||
2442 2443
		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
2444 2445 2446 2447 2448 2449 2450
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2451
	} else
L
Linus Torvalds 已提交
2452 2453 2454 2455 2456
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2457 2458
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2459 2460 2461 2462 2463 2464
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2465
	} else
2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477
		*first = 0;

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

2478
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2479 2480 2481 2482
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2483
	int open_quote = 0;
L
Linus Torvalds 已提交
2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498

	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 {
2499 2500 2501 2502
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2503 2504 2505
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2506
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2507 2508 2509 2510 2511 2512 2513
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2514
	strcpy(in_save, nosec_save);
2515
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2516 2517 2518 2519
out:
	return rc;
}

2520
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2521
{
2522
	const struct cred *cred = current_cred();
2523
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2524 2525 2526 2527 2528 2529
	int rc;

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

2530 2531 2532 2533
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2534
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2535
	ad.u.fs.path.dentry = sb->s_root;
2536
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2537 2538
}

2539
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2540
{
2541
	const struct cred *cred = current_cred();
2542
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2543

2544
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2545
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2546
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2547 2548
}

2549
static int selinux_mount(char *dev_name,
2550
			 struct path *path,
2551 2552 2553
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2554
{
2555
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2556 2557

	if (flags & MS_REMOUNT)
2558
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2559
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2560
	else
2561
		return dentry_has_perm(cred, path->mnt, path->dentry,
2562
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2563 2564 2565 2566
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2567
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2568

2569
	return superblock_has_perm(cred, mnt->mnt_sb,
2570
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584
}

/* 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);
}

2585 2586 2587 2588
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2589 2590
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2591 2592
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2593
	u32 sid, newsid, clen;
2594
	int rc;
2595
	char *namep = NULL, *context;
2596 2597 2598 2599

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

2600 2601 2602
	sid = tsec->sid;
	newsid = tsec->create_sid;

2603
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2604
		rc = security_transition_sid(sid, dsec->sid,
2605 2606 2607 2608 2609 2610
					     inode_mode_to_security_class(inode->i_mode),
					     &newsid);
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2611
			       __func__,
2612 2613 2614 2615 2616
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2617
	/* Possibly defer initialization to selinux_complete_init. */
2618
	if (sbsec->flags & SE_SBINITIALIZED) {
2619 2620 2621 2622 2623
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2624

2625
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2626 2627
		return -EOPNOTSUPP;

2628
	if (name) {
2629
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2630 2631 2632 2633
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2634

2635
	if (value && len) {
2636
		rc = security_sid_to_context_force(newsid, &context, &clen);
2637 2638 2639 2640 2641 2642
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2643 2644 2645 2646 2647
	}

	return 0;
}

L
Linus Torvalds 已提交
2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

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

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

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

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

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

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

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2684
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2685 2686 2687 2688 2689 2690
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2691 2692 2693
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2694 2695 2696 2697
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2698
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2699

2700
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2701 2702
}

2703
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2704
{
2705
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2706 2707 2708 2709 2710 2711

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

2712
	return inode_has_perm(cred, inode,
2713
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2714 2715 2716 2717
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2718
	const struct cred *cred = current_cred();
2719
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2720

2721 2722 2723 2724 2725 2726 2727
	/* 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
2728

2729 2730
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2731
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2732

2733
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2734 2735 2736 2737
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2738 2739 2740
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2741 2742
}

2743
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2744
{
2745 2746
	const struct cred *cred = current_cred();

2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760
	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. */
2761
	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2762 2763
}

2764 2765
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
2766 2767 2768 2769
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2770
	struct common_audit_data ad;
2771
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2772 2773
	int rc = 0;

2774 2775
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2776 2777

	sbsec = inode->i_sb->s_security;
2778
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2779 2780
		return -EOPNOTSUPP;

2781
	if (!is_owner_or_cap(inode))
L
Linus Torvalds 已提交
2782 2783
		return -EPERM;

2784
	COMMON_AUDIT_DATA_INIT(&ad, FS);
2785
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2786

2787
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2788 2789 2790 2791 2792
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2793 2794 2795 2796 2797
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2798 2799 2800
	if (rc)
		return rc;

2801
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2802 2803 2804 2805
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2806
	rc = security_validate_transition(isec->sid, newsid, sid,
2807
					  isec->sclass);
L
Linus Torvalds 已提交
2808 2809 2810 2811 2812 2813 2814 2815 2816 2817
	if (rc)
		return rc;

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

2818
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2819
					const void *value, size_t size,
2820
					int flags)
L
Linus Torvalds 已提交
2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

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

2832
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2833
	if (rc) {
2834 2835 2836
		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
2837 2838 2839 2840 2841 2842 2843
		return;
	}

	isec->sid = newsid;
	return;
}

2844
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2845
{
2846 2847 2848
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2849 2850
}

2851
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2852
{
2853 2854 2855
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2856 2857
}

2858
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2859
{
2860 2861
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2862 2863 2864 2865 2866 2867

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

2868
/*
2869
 * Copy the inode security context value to the user.
2870 2871 2872
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2873
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2874
{
2875 2876 2877
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2878
	struct inode_security_struct *isec = inode->i_security;
2879

2880 2881
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2882

2883 2884 2885 2886 2887 2888 2889 2890 2891
	/*
	 * 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.
	 */
2892 2893
	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
				SECURITY_CAP_NOAUDIT);
2894 2895 2896 2897 2898
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2899 2900 2901 2902 2903 2904 2905 2906 2907 2908
	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
2909 2910 2911
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2912
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923
{
	struct inode_security_struct *isec = inode->i_security;
	u32 newsid;
	int rc;

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

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

2924
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2925 2926 2927 2928
	if (rc)
		return rc;

	isec->sid = newsid;
2929
	isec->initialized = 1;
L
Linus Torvalds 已提交
2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940
	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;
}

2941 2942 2943 2944 2945 2946
static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
{
	struct inode_security_struct *isec = inode->i_security;
	*secid = isec->sid;
}

L
Linus Torvalds 已提交
2947 2948
/* file security operations */

2949
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2950
{
2951
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2952
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2953 2954 2955 2956 2957

	/* 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;

2958 2959
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2960 2961
}

2962 2963
static int selinux_file_permission(struct file *file, int mask)
{
2964 2965 2966 2967 2968
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2969
	if (!mask)
2970 2971 2972
		/* No permission to check.  Existence test. */
		return 0;

2973 2974 2975 2976 2977
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2978 2979 2980
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993
static int selinux_file_alloc_security(struct file *file)
{
	return file_alloc_security(file);
}

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

static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
2994
	const struct cred *cred = current_cred();
2995
	u32 av = 0;
L
Linus Torvalds 已提交
2996

2997 2998 2999 3000 3001 3002
	if (_IOC_DIR(cmd) & _IOC_WRITE)
		av |= FILE__WRITE;
	if (_IOC_DIR(cmd) & _IOC_READ)
		av |= FILE__READ;
	if (!av)
		av = FILE__IOCTL;
L
Linus Torvalds 已提交
3003

3004
	return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3005 3006 3007 3008
}

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3009
	const struct cred *cred = current_cred();
D
David Howells 已提交
3010
	int rc = 0;
3011

L
Linus Torvalds 已提交
3012 3013 3014 3015 3016 3017 3018
#ifndef CONFIG_PPC32
	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
D
David Howells 已提交
3019
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3020
		if (rc)
D
David Howells 已提交
3021
			goto error;
L
Linus Torvalds 已提交
3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035
	}
#endif

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

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

		if (prot & PROT_EXEC)
			av |= FILE__EXECUTE;

3036
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3037
	}
D
David Howells 已提交
3038 3039 3040

error:
	return rc;
L
Linus Torvalds 已提交
3041 3042 3043
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3044 3045
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3046
{
3047
	int rc = 0;
3048
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3049

3050 3051 3052 3053 3054 3055
	/*
	 * notice that we are intentionally putting the SELinux check before
	 * the secondary cap_file_mmap check.  This is such a likely attempt
	 * at bad behaviour/exploit that we always want to get the AVC, even
	 * if DAC would have also denied the operation.
	 */
3056
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3057 3058
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3059 3060 3061 3062 3063 3064
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3065
	if (rc || addr_only)
L
Linus Torvalds 已提交
3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

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

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3079
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3080 3081 3082 3083 3084

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3085
	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3086
		int rc = 0;
3087 3088
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3089
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3090 3091 3092
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3093
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3094 3095 3096 3097 3098 3099 3100 3101
		} 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
3102
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3103
		}
3104 3105 3106
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3107 3108 3109 3110 3111 3112 3113
#endif

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

static int selinux_file_lock(struct file *file, unsigned int cmd)
{
3114 3115 3116
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3117 3118 3119 3120 3121
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3122
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3123 3124 3125
	int err = 0;

	switch (cmd) {
3126 3127 3128 3129 3130
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3131

3132
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3133
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3134
			break;
3135 3136 3137 3138 3139 3140 3141 3142
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3143
		err = file_has_perm(cred, file, 0);
3144 3145 3146 3147
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3148
#if BITS_PER_LONG == 32
3149 3150 3151
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3152
#endif
3153 3154
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3155
			break;
3156
		}
3157
		err = file_has_perm(cred, file, FILE__LOCK);
3158
		break;
L
Linus Torvalds 已提交
3159 3160 3161 3162 3163 3164 3165 3166 3167 3168
	}

	return err;
}

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

	fsec = file->f_security;
3169
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3170 3171 3172 3173 3174 3175 3176

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3177
	struct file *file;
3178
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3179 3180 3181 3182
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3183
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3184 3185 3186 3187 3188 3189 3190 3191

	fsec = file->f_security;

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

3192
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3193 3194 3195 3196 3197
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3198 3199 3200
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3201 3202
}

3203
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3204 3205 3206 3207
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3208

3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3229
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3230 3231
}

L
Linus Torvalds 已提交
3232 3233 3234 3235
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3236
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3237 3238
}

3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253
/*
 * 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
3254 3255 3256 3257
/*
 * 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
3258
{
D
David Howells 已提交
3259
	struct task_security_struct *tsec = cred->security;
3260 3261 3262

	BUG_ON((unsigned long) cred->security < PAGE_SIZE);
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3263 3264
	kfree(tsec);
}
L
Linus Torvalds 已提交
3265

D
David Howells 已提交
3266 3267 3268 3269 3270 3271 3272 3273
/*
 * 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
3274

D
David Howells 已提交
3275
	old_tsec = old->security;
L
Linus Torvalds 已提交
3276

D
David Howells 已提交
3277 3278 3279
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3280

D
David Howells 已提交
3281
	new->security = tsec;
L
Linus Torvalds 已提交
3282 3283 3284
	return 0;
}

3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295
/*
 * 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;
}

3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 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
/*
 * set the security data for a kernel service
 * - all the creation contexts are set to unlabelled
 */
static int selinux_kernel_act_as(struct cred *new, u32 secid)
{
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

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

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

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

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

3340
static int selinux_kernel_module_request(char *kmod_name)
3341
{
3342 3343 3344 3345 3346 3347 3348 3349 3350 3351
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3352 3353
}

L
Linus Torvalds 已提交
3354 3355
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3356
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3357 3358 3359 3360
}

static int selinux_task_getpgid(struct task_struct *p)
{
3361
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3362 3363 3364 3365
}

static int selinux_task_getsid(struct task_struct *p)
{
3366
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3367 3368
}

3369 3370
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3371
	*secid = task_sid(p);
3372 3373
}

L
Linus Torvalds 已提交
3374 3375 3376 3377
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3378
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3379 3380 3381
	if (rc)
		return rc;

3382
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3383 3384
}

3385 3386
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3387 3388
	int rc;

3389
	rc = cap_task_setioprio(p, ioprio);
3390 3391 3392
	if (rc)
		return rc;

3393
	return current_has_perm(p, PROCESS__SETSCHED);
3394 3395
}

3396 3397
static int selinux_task_getioprio(struct task_struct *p)
{
3398
	return current_has_perm(p, PROCESS__GETSCHED);
3399 3400
}

L
Linus Torvalds 已提交
3401 3402 3403 3404 3405 3406 3407
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
	struct rlimit *old_rlim = current->signal->rlim + resource;

	/* Control the ability to change the hard limit (whether
	   lowering or raising it), so that the hard limit can
	   later be used as a safe reset point for the soft limit
D
David Howells 已提交
3408
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3409
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3410
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3411 3412 3413 3414 3415 3416

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3417 3418
	int rc;

3419
	rc = cap_task_setscheduler(p, policy, lp);
3420 3421 3422
	if (rc)
		return rc;

3423
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3424 3425 3426 3427
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3428
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3429 3430
}

3431 3432
static int selinux_task_movememory(struct task_struct *p)
{
3433
	return current_has_perm(p, PROCESS__SETSCHED);
3434 3435
}

3436 3437
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3438 3439 3440 3441 3442 3443 3444 3445
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3446
	if (secid)
3447 3448
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3449
	else
3450
		rc = current_has_perm(p, perm);
3451
	return rc;
L
Linus Torvalds 已提交
3452 3453 3454 3455
}

static int selinux_task_wait(struct task_struct *p)
{
3456
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3457 3458 3459 3460 3461 3462
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3463
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3464

3465
	isec->sid = sid;
L
Linus Torvalds 已提交
3466 3467 3468 3469
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3470
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3471
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3472 3473 3474 3475
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3476
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

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

3489 3490 3491
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3492
	switch (ih->protocol) {
3493 3494
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3495

3496 3497
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3498 3499 3500 3501 3502 3503 3504 3505 3506

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

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3507 3508 3509 3510 3511 3512 3513 3514
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3515
		offset += ihlen;
3516
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3517
		if (uh == NULL)
3518
			break;
L
Linus Torvalds 已提交
3519

3520 3521 3522 3523
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3524

J
James Morris 已提交
3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3539
	}
J
James Morris 已提交
3540

3541 3542 3543
	default:
		break;
	}
L
Linus Torvalds 已提交
3544 3545 3546 3547 3548 3549 3550
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3551
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3552
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3553 3554 3555 3556 3557
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3558
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3559 3560 3561 3562 3563 3564 3565 3566 3567 3568
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

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

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3569
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3570 3571 3572
	if (offset < 0)
		goto out;

3573 3574 3575
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3576 3577
	switch (nexthdr) {
	case IPPROTO_TCP: {
3578
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600

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

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

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

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

J
James Morris 已提交
3601 3602 3603 3604 3605 3606 3607 3608 3609 3610
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3611
	}
J
James Morris 已提交
3612

L
Linus Torvalds 已提交
3613 3614 3615 3616 3617 3618 3619 3620 3621 3622
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3623
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3624
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3625
{
3626 3627
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3628 3629 3630

	switch (ad->u.net.family) {
	case PF_INET:
3631
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3632 3633 3634 3635 3636
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3637 3638 3639

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3640
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3641 3642 3643 3644 3645
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3646 3647
#endif	/* IPV6 */
	default:
3648 3649
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3650 3651
	}

3652 3653 3654 3655
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3656
	return ret;
3657 3658 3659 3660 3661

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3662 3663
}

3664
/**
3665
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3666
 * @skb: the packet
3667
 * @family: protocol family
3668
 * @sid: the packet's peer label SID
3669 3670
 *
 * Description:
3671 3672 3673 3674 3675 3676
 * 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.
3677 3678
 *
 */
3679
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3680
{
3681
	int err;
3682 3683
	u32 xfrm_sid;
	u32 nlbl_sid;
3684
	u32 nlbl_type;
3685 3686

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3687
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3688

3689 3690 3691 3692 3693
	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");
3694
		return -EACCES;
3695
	}
3696 3697

	return 0;
3698 3699
}

L
Linus Torvalds 已提交
3700 3701 3702 3703 3704
/* socket security operations */
static int socket_has_perm(struct task_struct *task, struct socket *sock,
			   u32 perms)
{
	struct inode_security_struct *isec;
3705
	struct common_audit_data ad;
3706
	u32 sid;
L
Linus Torvalds 已提交
3707 3708 3709 3710 3711 3712
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3713
	sid = task_sid(task);
L
Linus Torvalds 已提交
3714

3715
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3716
	ad.u.net.sk = sock->sk;
3717
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3718 3719 3720 3721 3722 3723 3724 3725

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3726 3727 3728 3729
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, newsid;
	u16 secclass;
L
Linus Torvalds 已提交
3730 3731 3732 3733 3734
	int err = 0;

	if (kern)
		goto out;

3735 3736 3737 3738 3739
	sid = tsec->sid;
	newsid = tsec->sockcreate_sid ?: sid;

	secclass = socket_type_to_security_class(family, type, protocol);
	err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3740 3741 3742 3743 3744

out:
	return err;
}

V
Venkat Yekkirala 已提交
3745 3746
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3747
{
3748 3749
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3750
	struct inode_security_struct *isec;
3751
	struct sk_security_struct *sksec;
3752 3753 3754 3755 3756
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3757 3758 3759

	isec = SOCK_INODE(sock)->i_security;

3760 3761 3762 3763 3764 3765 3766
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3767 3768 3769
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3770 3771 3772
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3773
		sksec->sclass = isec->sclass;
3774
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3775 3776
	}

V
Venkat Yekkirala 已提交
3777
	return err;
L
Linus Torvalds 已提交
3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794
}

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

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

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

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3795 3796
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3797 3798 3799 3800 3801
	 */
	family = sock->sk->sk_family;
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
		struct inode_security_struct *isec;
3802
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3803 3804 3805 3806
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
		struct sock *sk = sock->sk;
3807
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820

		isec = SOCK_INODE(sock)->i_security;

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

3821 3822 3823 3824 3825 3826
		if (snum) {
			int low, high;

			inet_get_local_port_range(&low, &high);

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3827 3828
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3829 3830
				if (err)
					goto out;
3831
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3832 3833 3834 3835 3836 3837 3838 3839
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
				err = avc_has_perm(isec->sid, sid,
						   isec->sclass,
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3840
		}
3841 3842

		switch (isec->sclass) {
3843
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3844 3845
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3846

3847
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3848 3849
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3850 3851 3852 3853 3854

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3855 3856 3857 3858
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3859

3860
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3861 3862
		if (err)
			goto out;
3863

3864
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3865 3866 3867 3868 3869 3870 3871 3872 3873
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

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

		err = avc_has_perm(isec->sid, sid,
3874
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3875 3876 3877 3878 3879 3880 3881 3882 3883
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3884
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3885 3886 3887 3888 3889 3890 3891 3892
	struct inode_security_struct *isec;
	int err;

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

	/*
J
James Morris 已提交
3893
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3894 3895
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3896 3897
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
3898
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3899 3900 3901
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3902
		u32 sid, perm;
L
Linus Torvalds 已提交
3903 3904 3905

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3906
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3907 3908 3909 3910
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3911
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3912 3913 3914 3915
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3916
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3917 3918 3919
		if (err)
			goto out;

J
James Morris 已提交
3920 3921 3922
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3923
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3924 3925
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3926
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3927 3928 3929 3930
		if (err)
			goto out;
	}

3931 3932
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962
out:
	return err;
}

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

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

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

	newisec = SOCK_INODE(newsock)->i_security;

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

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3963
				  int size)
L
Linus Torvalds 已提交
3964
{
3965
	return socket_has_perm(current, sock, SOCKET__WRITE);
L
Linus Torvalds 已提交
3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983
}

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

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

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

3984
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3985
{
3986 3987 3988 3989 3990 3991 3992
	int err;

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

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012
}

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

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

static int selinux_socket_unix_stream_connect(struct socket *sock,
					      struct socket *other,
					      struct sock *newsk)
{
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
4013
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4014 4015 4016 4017 4018
	int err;

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

4019
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030
	ad.u.net.sk = other->sk;

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

	/* connecting socket */
	ssec = sock->sk->sk_security;
	ssec->peer_sid = other_isec->sid;
4031

L
Linus Torvalds 已提交
4032 4033 4034
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
4035 4036 4037
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
4038 4039 4040 4041 4042 4043 4044
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
4045
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4046 4047 4048 4049 4050
	int err;

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

4051
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4052 4053 4054 4055 4056 4057 4058 4059 4060 4061
	ad.u.net.sk = other->sk;

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

	return 0;
}

4062 4063
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4064
				    struct common_audit_data *ad)
4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084
{
	int err;
	u32 if_sid;
	u32 node_sid;

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

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

4085
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4086
				       u16 family)
4087
{
4088
	int err = 0;
4089 4090 4091
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4092
	struct common_audit_data ad;
4093 4094
	char *addrp;

4095
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4096
	ad.u.net.netif = skb->skb_iif;
4097 4098 4099 4100
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4101

4102
	if (selinux_secmark_enabled()) {
4103
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4104
				   PACKET__RECV, &ad);
4105 4106 4107
		if (err)
			return err;
	}
4108 4109 4110 4111 4112 4113

	if (selinux_policycap_netpeer) {
		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
		if (err)
			return err;
		err = avc_has_perm(sk_sid, peer_sid,
4114
				   SECCLASS_PEER, PEER__RECV, &ad);
4115 4116
		if (err)
			selinux_netlbl_err(skb, err, 0);
4117
	} else {
4118
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4119 4120
		if (err)
			return err;
4121
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4122
	}
4123

4124 4125 4126 4127 4128
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4129
	int err;
4130
	struct sk_security_struct *sksec = sk->sk_security;
4131 4132
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4133
	struct common_audit_data ad;
4134
	char *addrp;
4135 4136
	u8 secmark_active;
	u8 peerlbl_active;
4137 4138

	if (family != PF_INET && family != PF_INET6)
4139
		return 0;
4140 4141

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4142
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4143 4144
		family = PF_INET;

4145 4146 4147 4148
	/* 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. */
4149
	if (!selinux_policycap_netpeer)
4150 4151 4152 4153 4154 4155 4156
		return selinux_sock_rcv_skb_compat(sk, skb, family);

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

4157
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4158
	ad.u.net.netif = skb->skb_iif;
4159
	ad.u.net.family = family;
4160
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4161
	if (err)
4162
		return err;
4163

4164
	if (peerlbl_active) {
4165 4166 4167
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4168 4169
		if (err)
			return err;
4170
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4171
					       peer_sid, &ad);
4172 4173
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4174
			return err;
4175
		}
4176 4177
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4178 4179
		if (err)
			selinux_netlbl_err(skb, err, 0);
4180 4181
	}

4182
	if (secmark_active) {
4183 4184 4185 4186 4187 4188
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4189
	return err;
L
Linus Torvalds 已提交
4190 4191
}

C
Catherine Zhang 已提交
4192 4193
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4194 4195 4196 4197 4198 4199
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4200
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4201 4202

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4203

4204 4205
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4206 4207 4208
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4209
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4210 4211 4212 4213
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4214 4215
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231
	if (err)
		goto out;

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

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

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

	kfree(scontext);
4232
out:
L
Linus Torvalds 已提交
4233 4234 4235
	return err;
}

4236
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4237
{
4238
	u32 peer_secid = SECSID_NULL;
4239
	u16 family;
C
Catherine Zhang 已提交
4240

4241 4242 4243 4244 4245
	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)
4246 4247 4248 4249 4250
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4251
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4252
	else if (skb)
4253
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4254

4255
out:
4256
	*secid = peer_secid;
4257 4258 4259
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4260 4261
}

A
Al Viro 已提交
4262
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4263 4264 4265 4266 4267 4268 4269 4270 4271
{
	return sk_alloc_security(sk, family, priority);
}

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

4272
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4273
{
4274 4275
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4276

4277 4278
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4279
	newssec->sclass = ssec->sclass;
4280

4281
	selinux_netlbl_sk_security_reset(newssec);
4282 4283
}

V
Venkat Yekkirala 已提交
4284
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4285
{
4286
	if (!sk)
V
Venkat Yekkirala 已提交
4287
		*secid = SECINITSID_ANY_SOCKET;
4288 4289
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4290

V
Venkat Yekkirala 已提交
4291
		*secid = sksec->sid;
4292
	}
4293 4294
}

4295
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4296 4297 4298 4299
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4300 4301 4302
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4303
	sksec->sclass = isec->sclass;
4304 4305
}

4306 4307
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4308 4309 4310
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4311
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4312
	u32 newsid;
4313 4314
	u32 peersid;

4315 4316 4317 4318 4319
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4320 4321
	if (err)
		return err;
4322 4323
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4324
		req->peer_secid = SECSID_NULL;
4325 4326 4327 4328 4329 4330
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4331 4332
	}

4333
	return selinux_netlbl_inet_conn_request(req, family);
4334 4335
}

4336 4337
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4338 4339 4340 4341
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4342
	newsksec->peer_sid = req->peer_secid;
4343 4344 4345 4346
	/* 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. */
4347

P
Paul Moore 已提交
4348 4349
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4350
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4351 4352
}

4353
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4354
{
4355
	u16 family = sk->sk_family;
4356 4357
	struct sk_security_struct *sksec = sk->sk_security;

4358 4359 4360 4361 4362
	/* 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);
4363 4364
}

4365 4366
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4367 4368 4369 4370
{
	fl->secid = req->secid;
}

4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

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

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

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

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

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

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

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

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

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4424 4425 4426 4427 4428 4429 4430
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
	struct socket *sock = sk->sk_socket;
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4431

L
Linus Torvalds 已提交
4432 4433 4434 4435
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4436
	nlh = nlmsg_hdr(skb);
4437

L
Linus Torvalds 已提交
4438 4439 4440
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4441
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4442 4443 4444
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4445
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461
				err = 0;
		}

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

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

#ifdef CONFIG_NETFILTER

4462 4463
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4464
{
4465
	int err;
4466 4467
	char *addrp;
	u32 peer_sid;
4468
	struct common_audit_data ad;
4469
	u8 secmark_active;
4470
	u8 netlbl_active;
4471
	u8 peerlbl_active;
4472

4473 4474
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4475

4476
	secmark_active = selinux_secmark_enabled();
4477 4478
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4479 4480
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4481

4482 4483 4484
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4485
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4486 4487 4488 4489 4490
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4491 4492 4493 4494 4495
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4496
			return NF_DROP;
4497 4498
		}
	}
4499 4500 4501 4502 4503 4504

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

4505 4506 4507 4508 4509 4510 4511 4512
	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;

4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535
	return NF_ACCEPT;
}

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

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

4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
	u32 sid;

	if (!netlbl_enabled())
		return NF_ACCEPT;

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

	return NF_ACCEPT;
}

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

4567 4568
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4569
						u16 family)
4570 4571 4572
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4573
	struct common_audit_data ad;
4574 4575
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4576

4577 4578 4579 4580
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4581
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4582 4583 4584 4585 4586
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4587
	if (selinux_secmark_enabled())
4588
		if (avc_has_perm(sksec->sid, skb->secmark,
4589
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4590 4591 4592
			return NF_DROP;

	if (selinux_policycap_netpeer)
4593
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4594 4595 4596
			return NF_DROP;

	return NF_ACCEPT;
4597 4598
}

4599 4600
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4601
{
4602 4603
	u32 secmark_perm;
	u32 peer_sid;
4604
	struct sock *sk;
4605
	struct common_audit_data ad;
4606 4607 4608
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4609

4610 4611 4612 4613
	/* 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. */
4614
	if (!selinux_policycap_netpeer)
4615
		return selinux_ip_postroute_compat(skb, ifindex, family);
4616
#ifdef CONFIG_XFRM
4617 4618 4619 4620 4621 4622
	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
	 *       is NULL, in this case go ahead and apply access control. */
E
Eric Dumazet 已提交
4623
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4624
		return NF_ACCEPT;
4625
#endif
4626 4627 4628 4629 4630
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4631 4632 4633 4634
	/* if the packet is being forwarded then get the peer label from the
	 * packet itself; otherwise check to see if it is from a local
	 * application or the kernel, if from an application get the peer label
	 * from the sending socket, otherwise use the kernel's sid */
4635
	sk = skb->sk;
4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658
	if (sk == NULL) {
		switch (family) {
		case PF_INET:
			if (IPCB(skb)->flags & IPSKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		case PF_INET6:
			if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		default:
			return NF_DROP;
		}
		if (secmark_perm == PACKET__FORWARD_OUT) {
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
				return NF_DROP;
		} else
			peer_sid = SECINITSID_KERNEL;
	} else {
4659 4660 4661 4662
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4663

4664
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4665 4666 4667 4668 4669
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
		return NF_DROP;

4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687 4688 4689 4690
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
			return NF_DROP;

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

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

		if (sel_netnode_sid(addrp, family, &node_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
			return NF_DROP;
	}
4691

4692
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4693 4694
}

4695 4696 4697 4698 4699
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4700
{
4701
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4702 4703 4704
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4705 4706 4707 4708 4709
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4710
{
4711
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4712 4713 4714 4715 4716 4717 4718 4719 4720
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4721
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4722 4723 4724
	if (err)
		return err;

4725
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4726 4727
}

4728
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4729
{
4730
	int err;
4731
	struct common_audit_data ad;
4732

4733
	err = cap_netlink_recv(skb, capability);
4734 4735 4736
	if (err)
		return err;

4737
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4738 4739 4740
	ad.u.cap = capability;

	return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4741
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4742 4743 4744 4745 4746 4747 4748
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4749
	u32 sid;
L
Linus Torvalds 已提交
4750

J
James Morris 已提交
4751
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4752 4753 4754
	if (!isec)
		return -ENOMEM;

4755
	sid = task_sid(task);
L
Linus Torvalds 已提交
4756
	isec->sclass = sclass;
4757
	isec->sid = sid;
L
Linus Torvalds 已提交
4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773
	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
4774
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792
	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,
4793
			u32 perms)
L
Linus Torvalds 已提交
4794 4795
{
	struct ipc_security_struct *isec;
4796
	struct common_audit_data ad;
4797
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4798 4799 4800

	isec = ipc_perms->security;

4801
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4802 4803
	ad.u.ipc_id = ipc_perms->key;

4804
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820
}

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;
4821
	struct common_audit_data ad;
4822
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4823 4824 4825 4826 4827 4828 4829 4830
	int rc;

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

	isec = msq->q_perm.security;

4831
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4833

4834
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850
			  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;
4851
	struct common_audit_data ad;
4852
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4853 4854 4855

	isec = msq->q_perm.security;

4856
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4857 4858
	ad.u.ipc_id = msq->q_perm.key;

4859
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4860 4861 4862 4863 4864 4865 4866 4867
			    MSGQ__ASSOCIATE, &ad);
}

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

4868
	switch (cmd) {
L
Linus Torvalds 已提交
4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886
	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;
	}

4887
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4888 4889 4890 4891 4892 4893 4894
	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;
4895
	struct common_audit_data ad;
4896
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909
	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
		 */
4910
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
4911 4912 4913 4914 4915
					     &msec->sid);
		if (rc)
			return rc;
	}

4916
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4917 4918 4919
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4920
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4921 4922 4923
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4924 4925
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4926 4927
	if (!rc)
		/* Can the message be put in the queue? */
4928 4929
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4930 4931 4932 4933 4934 4935 4936 4937 4938 4939

	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;
4940
	struct common_audit_data ad;
4941
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4942 4943 4944 4945 4946
	int rc;

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

4947
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4949

4950
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4951 4952
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4953
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4954 4955 4956 4957 4958 4959 4960 4961
				  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;
4962
	struct common_audit_data ad;
4963
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4964 4965 4966 4967 4968 4969 4970 4971
	int rc;

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

	isec = shp->shm_perm.security;

4972
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4974

4975
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991
			  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;
4992
	struct common_audit_data ad;
4993
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4994 4995 4996

	isec = shp->shm_perm.security;

4997
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4998 4999
	ad.u.ipc_id = shp->shm_perm.key;

5000
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5001 5002 5003 5004 5005 5006 5007 5008 5009
			    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;

5010
	switch (cmd) {
L
Linus Torvalds 已提交
5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032
	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;
	}

5033
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046
	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;

5047
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5048 5049 5050 5051 5052 5053
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5054
	struct common_audit_data ad;
5055
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5056 5057 5058 5059 5060 5061 5062 5063
	int rc;

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

	isec = sma->sem_perm.security;

5064
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5066

5067
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083
			  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;
5084
	struct common_audit_data ad;
5085
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5086 5087 5088

	isec = sma->sem_perm.security;

5089
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
5090 5091
	ad.u.ipc_id = sma->sem_perm.key;

5092
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5093 5094 5095 5096 5097 5098 5099 5100 5101
			    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;

5102
	switch (cmd) {
L
Linus Torvalds 已提交
5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133
	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;
	}

5134
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147
	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;

5148
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163
}

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;

5164
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5165 5166
}

5167 5168 5169 5170 5171 5172
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5173
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5174 5175 5176 5177 5178 5179
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5180
			       char *name, char **value)
L
Linus Torvalds 已提交
5181
{
5182
	const struct task_security_struct *__tsec;
5183
	u32 sid;
L
Linus Torvalds 已提交
5184
	int error;
5185
	unsigned len;
L
Linus Torvalds 已提交
5186 5187

	if (current != p) {
5188
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5189 5190 5191 5192
		if (error)
			return error;
	}

5193 5194
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5195 5196

	if (!strcmp(name, "current"))
5197
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5198
	else if (!strcmp(name, "prev"))
5199
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5200
	else if (!strcmp(name, "exec"))
5201
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5202
	else if (!strcmp(name, "fscreate"))
5203
		sid = __tsec->create_sid;
5204
	else if (!strcmp(name, "keycreate"))
5205
		sid = __tsec->keycreate_sid;
5206
	else if (!strcmp(name, "sockcreate"))
5207
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5208
	else
5209 5210
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5211 5212 5213 5214

	if (!sid)
		return 0;

5215 5216 5217 5218
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5219 5220 5221 5222

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5223 5224 5225 5226 5227 5228
}

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
5229
	struct task_struct *tracer;
D
David Howells 已提交
5230 5231
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246
	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"))
5247
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5248
	else if (!strcmp(name, "fscreate"))
5249
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5250
	else if (!strcmp(name, "keycreate"))
5251
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252
	else if (!strcmp(name, "sockcreate"))
5253
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5254
	else if (!strcmp(name, "current"))
5255
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
	if (size && str[1] && str[1] != '\n') {
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
		error = security_context_to_sid(value, size, &sid);
5268 5269 5270 5271 5272 5273
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5274 5275 5276 5277
		if (error)
			return error;
	}

D
David Howells 已提交
5278 5279 5280 5281
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5282 5283 5284
	/* 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
5285
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5286 5287
	   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
5288 5289
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5290
		tsec->exec_sid = sid;
D
David Howells 已提交
5291
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5292
		tsec->create_sid = sid;
D
David Howells 已提交
5293
	} else if (!strcmp(name, "keycreate")) {
5294 5295
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5296
			goto abort_change;
5297
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5298
	} else if (!strcmp(name, "sockcreate")) {
5299
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5300 5301
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5302
		if (sid == 0)
D
David Howells 已提交
5303 5304 5305 5306
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5307
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5308 5309 5310
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5311
		}
L
Linus Torvalds 已提交
5312 5313 5314

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5316
		if (error)
D
David Howells 已提交
5317
			goto abort_change;
L
Linus Torvalds 已提交
5318 5319 5320

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5321
		ptsid = 0;
L
Linus Torvalds 已提交
5322
		task_lock(p);
5323
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5324 5325 5326 5327 5328 5329 5330
		if (tracer)
			ptsid = task_sid(tracer);
		task_unlock(p);

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5331
			if (error)
D
David Howells 已提交
5332
				goto abort_change;
L
Linus Torvalds 已提交
5333 5334
		}

D
David Howells 已提交
5335 5336 5337 5338 5339 5340 5341
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5342
	return size;
D
David Howells 已提交
5343 5344 5345 5346

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5347 5348
}

5349 5350 5351 5352 5353
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5354
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355 5356 5357 5358
{
	return security_context_to_sid(secdata, seclen, secid);
}

5359 5360
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5361
	kfree(secdata);
5362 5363
}

5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389
/*
 *	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;
}
5390 5391
#ifdef CONFIG_KEYS

D
David Howells 已提交
5392
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393
			     unsigned long flags)
5394
{
D
David Howells 已提交
5395
	const struct task_security_struct *tsec;
5396 5397 5398 5399 5400 5401
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5402 5403 5404
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5405
	else
D
David Howells 已提交
5406
		ksec->sid = tsec->sid;
5407

5408
	k->security = ksec;
5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420
	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
5421 5422
				  const struct cred *cred,
				  key_perm_t perm)
5423 5424 5425
{
	struct key *key;
	struct key_security_struct *ksec;
5426
	u32 sid;
5427 5428 5429 5430 5431 5432 5433

	/* 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
5434
	sid = cred_sid(cred);
5435 5436 5437 5438 5439

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440 5441
}

5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455
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;
}

5456 5457
#endif

L
Linus Torvalds 已提交
5458
static struct security_operations selinux_ops = {
5459 5460
	.name =				"selinux",

5461
	.ptrace_access_check =		selinux_ptrace_access_check,
5462
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5463
	.capget =			selinux_capget,
D
David Howells 已提交
5464
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5465 5466 5467 5468 5469 5470 5471 5472
	.sysctl =			selinux_sysctl,
	.capable =			selinux_capable,
	.quotactl =			selinux_quotactl,
	.quota_on =			selinux_quota_on,
	.syslog =			selinux_syslog,
	.vm_enough_memory =		selinux_vm_enough_memory,

	.netlink_send =			selinux_netlink_send,
5473
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5474

5475 5476 5477
	.bprm_set_creds =		selinux_bprm_set_creds,
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5478 5479 5480 5481 5482
	.bprm_secureexec =		selinux_bprm_secureexec,

	.sb_alloc_security =		selinux_sb_alloc_security,
	.sb_free_security =		selinux_sb_free_security,
	.sb_copy_data =			selinux_sb_copy_data,
5483
	.sb_kern_mount =		selinux_sb_kern_mount,
5484
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5485 5486 5487
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5488
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5489
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5490 5491
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5492 5493 5494

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5495
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513
	.inode_create =			selinux_inode_create,
	.inode_link =			selinux_inode_link,
	.inode_unlink =			selinux_inode_unlink,
	.inode_symlink =		selinux_inode_symlink,
	.inode_mkdir =			selinux_inode_mkdir,
	.inode_rmdir =			selinux_inode_rmdir,
	.inode_mknod =			selinux_inode_mknod,
	.inode_rename =			selinux_inode_rename,
	.inode_readlink =		selinux_inode_readlink,
	.inode_follow_link =		selinux_inode_follow_link,
	.inode_permission =		selinux_inode_permission,
	.inode_setattr =		selinux_inode_setattr,
	.inode_getattr =		selinux_inode_getattr,
	.inode_setxattr =		selinux_inode_setxattr,
	.inode_post_setxattr =		selinux_inode_post_setxattr,
	.inode_getxattr =		selinux_inode_getxattr,
	.inode_listxattr =		selinux_inode_listxattr,
	.inode_removexattr =		selinux_inode_removexattr,
5514 5515 5516
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5517
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530

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

5531
	.dentry_open =			selinux_dentry_open,
5532

L
Linus Torvalds 已提交
5533
	.task_create =			selinux_task_create,
5534
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5535
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5536
	.cred_prepare =			selinux_cred_prepare,
5537
	.cred_transfer =		selinux_cred_transfer,
5538 5539
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5540
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5541 5542
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5543
	.task_getsid =			selinux_task_getsid,
5544
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5545
	.task_setnice =			selinux_task_setnice,
5546
	.task_setioprio =		selinux_task_setioprio,
5547
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5548 5549 5550
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5551
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5552 5553
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5554
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5555 5556

	.ipc_permission =		selinux_ipc_permission,
5557
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574

	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
	.msg_msg_free_security =	selinux_msg_msg_free_security,

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

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

5575 5576
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5577 5578 5579 5580
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5581
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5582

5583 5584
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5585

5586
	.secid_to_secctx =		selinux_secid_to_secctx,
5587
	.secctx_to_secid =		selinux_secctx_to_secid,
5588
	.release_secctx =		selinux_release_secctx,
5589 5590 5591
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5592

5593
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609
	.unix_may_send =		selinux_socket_unix_may_send,

	.socket_create =		selinux_socket_create,
	.socket_post_create =		selinux_socket_post_create,
	.socket_bind =			selinux_socket_bind,
	.socket_connect =		selinux_socket_connect,
	.socket_listen =		selinux_socket_listen,
	.socket_accept =		selinux_socket_accept,
	.socket_sendmsg =		selinux_socket_sendmsg,
	.socket_recvmsg =		selinux_socket_recvmsg,
	.socket_getsockname =		selinux_socket_getsockname,
	.socket_getpeername =		selinux_socket_getpeername,
	.socket_getsockopt =		selinux_socket_getsockopt,
	.socket_setsockopt =		selinux_socket_setsockopt,
	.socket_shutdown =		selinux_socket_shutdown,
	.socket_sock_rcv_skb =		selinux_socket_sock_rcv_skb,
C
Catherine Zhang 已提交
5610 5611
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5612 5613
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5614
	.sk_clone_security =		selinux_sk_clone_security,
5615
	.sk_getsecid =			selinux_sk_getsecid,
5616 5617 5618
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5619
	.inet_conn_established =	selinux_inet_conn_established,
5620
	.req_classify_flow =		selinux_req_classify_flow,
5621 5622 5623
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5624 5625 5626 5627 5628

#ifdef CONFIG_SECURITY_NETWORK_XFRM
	.xfrm_policy_alloc_security =	selinux_xfrm_policy_alloc,
	.xfrm_policy_clone_security =	selinux_xfrm_policy_clone,
	.xfrm_policy_free_security =	selinux_xfrm_policy_free,
C
Catherine Zhang 已提交
5629
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5630 5631
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5632
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5633
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5634 5635
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5636
#endif
5637 5638

#ifdef CONFIG_KEYS
5639 5640 5641
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5642
	.key_getsecurity =		selinux_key_getsecurity,
5643
#endif
5644 5645 5646 5647 5648 5649 5650

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
Linus Torvalds 已提交
5651 5652 5653 5654
};

static __init int selinux_init(void)
{
5655 5656 5657 5658 5659
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5660 5661 5662 5663 5664 5665 5666 5667
	if (!selinux_enabled) {
		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
		return 0;
	}

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

	/* Set the security state for the initial task. */
D
David Howells 已提交
5668
	cred_init_security();
L
Linus Torvalds 已提交
5669

5670 5671
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5672
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5673 5674
	avc_init();

5675
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5676
	if (!secondary_ops)
5677 5678
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5679 5680
		panic("SELinux: Unable to register with kernel.\n");

5681
	if (selinux_enforcing)
5682
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5683
	else
5684
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5685

L
Linus Torvalds 已提交
5686 5687 5688 5689 5690
	return 0;
}

void selinux_complete_init(void)
{
5691
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5692 5693

	/* Set up any superblocks initialized prior to the policy load. */
5694
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5695
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5696 5697 5698 5699 5700
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5701 5702
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5703 5704 5705
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5706
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5707 5708 5709 5710
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5711
		spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5712 5713 5714 5715 5716
		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5717
	spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5718 5719 5720 5721 5722 5723
}

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

5724
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5725

5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5740 5741 5742 5743 5744 5745 5746
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5747
	}
L
Linus Torvalds 已提交
5748 5749 5750 5751
};

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

5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5767 5768 5769 5770 5771 5772 5773 5774 5775 5776
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5777 5778 5779

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

5780 5781 5782
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
5783 5784

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5785 5786 5787
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
5788
#endif	/* IPV6 */
5789

L
Linus Torvalds 已提交
5790 5791 5792 5793 5794 5795 5796 5797 5798
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5799
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5800

5801
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5802
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5803
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5804 5805 5806 5807
#endif	/* IPV6 */
}
#endif

5808
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5809 5810 5811 5812 5813

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5814
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5815 5816

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5817 5818
static int selinux_disabled;

L
Linus Torvalds 已提交
5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835
int selinux_disable(void)
{
	extern void exit_sel_fs(void);

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

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

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

	selinux_disabled = 1;
5836
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5837 5838 5839 5840

	/* Reset security_ops to the secondary module, dummy or capability. */
	security_ops = secondary_ops;

5841 5842 5843
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5844 5845 5846 5847 5848 5849 5850 5851 5852
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif