hooks.c 144.1 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
#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>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/sock.h>
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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 <linux/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
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#include <net/netlink.h>
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#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
	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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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)
{
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	const struct task_security_struct *tsec = current_security();
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	return tsec->sid;
}

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

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

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

	return 0;
}

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

	return 0;
}

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

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

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static const char *labeling_behaviors[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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	Opt_nextmntopt = 6,
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};

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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

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

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

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

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

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

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

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static int 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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	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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	sbsec->flags |= SE_SBINITIALIZED;
	if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
	    sbsec->behavior == SECURITY_FS_USE_TRANS ||
	    sbsec->behavior == SECURITY_FS_USE_TASK)
		sbsec->flags |= SBLABEL_MNT;
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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)
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		sbsec->flags |= SBLABEL_MNT;
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	/*
	 * Special handling for rootfs. Is genfs but supports
	 * setting SELinux context on in-core inodes.
	 */
	if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
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		sbsec->flags |= SBLABEL_MNT;
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	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
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	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
		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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	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

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	tmp = sbsec->flags & SE_MNTMASK;
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	/* count the number of mount options for this sb */
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	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
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		if (tmp & 0x01)
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			opts->num_mnt_opts++;
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		tmp >>= 1;
	}
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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 & SBLABEL_MNT) {
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		opts->mnt_opts[i] = NULL;
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		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
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	}
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	BUG_ON(i != opts->num_mnt_opts);
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	return 0;

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

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	/* check if the old mount command had the same options */
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	if (sbsec->flags & SE_SBINITIALIZED)
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		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
	 */
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	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
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			return 1;
	return 0;
}
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/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
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static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
562
{
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	const struct cred *cred = current_cred();
564 565 566
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
567 568
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
569 570
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
571 572 573
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
574 575 576 577 578 579 580 581 582 583 584

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
585 586
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
587
		goto out;
588
	}
L
Linus Torvalds 已提交
589

590 591 592 593 594 595 596 597 598 599 600
	/*
	 * 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)
	 */
601
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
602
	    && (num_opts == 0))
603
		goto out;
604

605 606 607 608 609 610 611
	/*
	 * 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;
612

613
		if (flags[i] == SBLABEL_MNT)
614
			continue;
615 616
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
617 618 619
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664
			       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
665
		}
666 667
	}

668
	if (sbsec->flags & SE_SBINITIALIZED) {
669
		/* previously mounted with options, but not on this attempt? */
670
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
671 672 673 674 675
			goto out_double_mount;
		rc = 0;
		goto out;
	}

676
	if (strcmp(sb->s_type->name, "proc") == 0)
677
		sbsec->flags |= SE_SBPROC;
678 679

	/* Determine the labeling behavior to use for this filesystem type. */
680
	rc = security_fs_use(sb);
681 682
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
683
		       __func__, sb->s_type->name, rc);
684 685
		goto out;
	}
L
Linus Torvalds 已提交
686

687 688
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
689
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
690
		if (rc)
691
			goto out;
L
Linus Torvalds 已提交
692

693
		sbsec->sid = fscontext_sid;
694 695 696 697 698 699 700
	}

	/*
	 * 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.
	 */
701 702
	if (context_sid) {
		if (!fscontext_sid) {
703 704
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
705
			if (rc)
706 707
				goto out;
			sbsec->sid = context_sid;
708
		} else {
709 710
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
711
			if (rc)
712
				goto out;
713
		}
714 715
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
716

717
		sbsec->mntpoint_sid = context_sid;
718
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
719 720
	}

721
	if (rootcontext_sid) {
722 723
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
724
		if (rc)
725
			goto out;
726

727 728
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
729 730
	}

731 732 733 734 735 736
	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
737 738
		}

739 740
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
741
							     sbsec, cred);
742 743 744
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
745

746
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
747 748
	}

749
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
750
out:
751
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
752
	return rc;
753 754 755 756 757
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
758 759
}

760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790
static int selinux_cmp_sb_context(const struct super_block *oldsb,
				    const struct super_block *newsb)
{
	struct superblock_security_struct *old = oldsb->s_security;
	struct superblock_security_struct *new = newsb->s_security;
	char oldflags = old->flags & SE_MNTMASK;
	char newflags = new->flags & SE_MNTMASK;

	if (oldflags != newflags)
		goto mismatch;
	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
		goto mismatch;
	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
		goto mismatch;
	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
		goto mismatch;
	if (oldflags & ROOTCONTEXT_MNT) {
		struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
		struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
			    "different security settings for (dev %s, "
			    "type %s)\n", newsb->s_id, newsb->s_type->name);
	return -EBUSY;
}

static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
791
					struct super_block *newsb)
L
Linus Torvalds 已提交
792
{
793 794
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
795

796 797 798
	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
799

800 801
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
802
	 * mount options.  thus we can safely deal with this superblock later
803
	 */
804
	if (!ss_initialized)
805
		return 0;
806 807

	/* how can we clone if the old one wasn't set up?? */
808
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
809

810
	/* if fs is reusing a sb, make sure that the contexts match */
811
	if (newsbsec->flags & SE_SBINITIALIZED)
812
		return selinux_cmp_sb_context(oldsb, newsb);
813

814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
	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
833
	}
834 835 836 837 838
	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
839

840
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
841 842
	}

843 844
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
845
	return 0;
846 847
}

848 849
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
850
{
851
	char *p;
852 853
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
854
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
855

856
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
857

858 859 860 861
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
862

863 864
		if (!*p)
			continue;
L
Linus Torvalds 已提交
865

866
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
867

868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919
		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;
920 921
		case Opt_labelsupport:
			break;
922 923 924 925
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
926 927 928

		}
	}
929

930 931 932 933 934 935 936 937 938 939 940
	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;
	}

941
	if (fscontext) {
942 943
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
944 945
	}
	if (context) {
946 947
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
948 949
	}
	if (rootcontext) {
950 951
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
952 953
	}
	if (defcontext) {
954 955
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
956 957
	}

958 959 960
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

961 962 963 964 965
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
966 967
	return rc;
}
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994
/*
 * 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
995

A
Adrian Bunk 已提交
996 997
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
998 999 1000 1001 1002
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1003 1004 1005 1006 1007 1008
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022

		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;
1023
		case SBLABEL_MNT:
1024 1025 1026
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1027 1028
		default:
			BUG();
1029
			return;
1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047
		};
		/* 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);
1048 1049 1050 1051
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1052
		return rc;
1053
	}
1054 1055 1056 1057 1058 1059 1060 1061

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
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;
}

1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
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
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110
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:
1111 1112 1113 1114
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1115
		case SOCK_DGRAM:
1116 1117 1118 1119
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1120 1121
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1122
		default:
L
Linus Torvalds 已提交
1123 1124 1125 1126 1127 1128 1129 1130 1131
			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;
1132
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145
			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;
1146 1147
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1148 1149 1150 1151 1152 1153 1154
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1155 1156
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1157 1158 1159 1160 1161 1162
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1163
static int selinux_proc_get_sid(struct dentry *dentry,
L
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1164 1165 1166
				u16 tclass,
				u32 *sid)
{
1167 1168
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1169

1170
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
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1171 1172 1173
	if (!buffer)
		return -ENOMEM;

1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
		/* each process gets a /proc/PID/ entry. Strip off the
		 * PID part to get a valid selinux labeling.
		 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
		while (path[1] >= '0' && path[1] <= '9') {
			path[1] = '/';
			path++;
		}
		rc = security_genfs_sid("proc", path, tclass, sid);
L
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1186 1187 1188 1189 1190
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1191
static int selinux_proc_get_sid(struct dentry *dentry,
L
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1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213
				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;

1214
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1215
	if (isec->initialized)
1216
		goto out_unlock;
L
Linus Torvalds 已提交
1217 1218

	sbsec = inode->i_sb->s_security;
1219
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1220 1221 1222 1223 1224 1225 1226
		/* 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);
1227
		goto out_unlock;
L
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1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246
	}

	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) {
1247 1248 1249 1250 1251 1252 1253 1254 1255
			/*
			 * 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.
			 */
1256
			goto out_unlock;
L
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1257 1258 1259
		}

		len = INITCONTEXTLEN;
1260
		context = kmalloc(len+1, GFP_NOFS);
L
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1261 1262 1263
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1264
			goto out_unlock;
L
Linus Torvalds 已提交
1265
		}
1266
		context[len] = '\0';
L
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1267 1268 1269
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1270 1271
			kfree(context);

L
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1272 1273 1274 1275 1276
			/* 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);
1277
				goto out_unlock;
L
Linus Torvalds 已提交
1278 1279
			}
			len = rc;
1280
			context = kmalloc(len+1, GFP_NOFS);
L
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1281 1282 1283
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1284
				goto out_unlock;
L
Linus Torvalds 已提交
1285
			}
1286
			context[len] = '\0';
L
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1287 1288 1289 1290 1291 1292 1293
			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
1294
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1295
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1296 1297
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1298
				goto out_unlock;
L
Linus Torvalds 已提交
1299 1300 1301 1302 1303
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1304
			rc = security_context_to_sid_default(context, rc, &sid,
1305 1306
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1307
			if (rc) {
1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338
				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);
1339 1340
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1341
		if (rc)
1342
			goto out_unlock;
L
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1343 1344
		isec->sid = sid;
		break;
1345 1346 1347
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1348
	default:
1349
		/* Default to the fs superblock SID. */
L
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1350 1351
		isec->sid = sbsec->sid;

1352
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1353
			if (opt_dentry) {
L
Linus Torvalds 已提交
1354
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1355
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1356 1357 1358
							  isec->sclass,
							  &sid);
				if (rc)
1359
					goto out_unlock;
L
Linus Torvalds 已提交
1360 1361 1362 1363 1364 1365 1366 1367
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1368 1369
out_unlock:
	mutex_unlock(&isec->lock);
L
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1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402
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
1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415
/*
 * 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);
}

1416
/*
1417
 * Check permission between a pair of tasks, e.g. signal checks,
1418 1419
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1420
 * - this uses the default subjective creds of tsk1
1421 1422 1423
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1424 1425
			 u32 perms)
{
1426 1427
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1428

1429 1430 1431 1432 1433
	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
1434 1435
}

1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451
/*
 * 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);
}

1452 1453 1454 1455
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1456
/* Check whether a task is allowed to use a capability. */
1457
static int cred_has_capability(const struct cred *cred,
1458
			       int cap, int audit)
L
Linus Torvalds 已提交
1459
{
1460
	struct common_audit_data ad;
1461
	struct av_decision avd;
1462
	u16 sclass;
1463
	u32 sid = cred_sid(cred);
1464
	u32 av = CAP_TO_MASK(cap);
1465
	int rc;
L
Linus Torvalds 已提交
1466

1467
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1468 1469
	ad.u.cap = cap;

1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480
	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();
1481
		return -EINVAL;
1482
	}
1483

1484
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1485 1486 1487 1488 1489
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1490
	return rc;
L
Linus Torvalds 已提交
1491 1492 1493 1494 1495 1496
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1497
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1498

1499
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1500 1501 1502 1503 1504 1505
			    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). */
1506
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1507 1508
			  struct inode *inode,
			  u32 perms,
1509 1510
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1511 1512
{
	struct inode_security_struct *isec;
1513
	u32 sid;
L
Linus Torvalds 已提交
1514

1515 1516
	validate_creds(cred);

1517
	if (unlikely(IS_PRIVATE(inode)))
1518 1519
		return 0;

1520
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1521 1522
	isec = inode->i_security;

1523
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1524 1525 1526 1527 1528
}

/* 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. */
1529
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1530 1531 1532 1533
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1534
	struct common_audit_data ad;
1535

1536
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550
	ad.u.dentry = dentry;
	return inode_has_perm(cred, inode, av, &ad, 0);
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the path to help the auditing code to more easily generate the
   pathname if needed. */
static inline int path_has_perm(const struct cred *cred,
				struct path *path,
				u32 av)
{
	struct inode *inode = path->dentry->d_inode;
	struct common_audit_data ad;

1551
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1552
	ad.u.path = *path;
1553
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1554 1555 1556 1557 1558 1559 1560 1561 1562 1563
}

/* 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. */
1564 1565 1566
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1567 1568
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1569
	struct inode *inode = file_inode(file);
1570
	struct common_audit_data ad;
1571
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1572 1573
	int rc;

1574
	ad.type = LSM_AUDIT_DATA_PATH;
1575
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1576

1577 1578
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1579 1580 1581 1582
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1583
			goto out;
L
Linus Torvalds 已提交
1584 1585 1586
	}

	/* av is zero if only checking access to the descriptor. */
1587
	rc = 0;
L
Linus Torvalds 已提交
1588
	if (av)
1589
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1590

1591 1592
out:
	return rc;
L
Linus Torvalds 已提交
1593 1594 1595 1596 1597 1598 1599
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1600
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1601 1602
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1603
	u32 sid, newsid;
1604
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1605 1606 1607 1608 1609
	int rc;

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

1610 1611 1612
	sid = tsec->sid;
	newsid = tsec->create_sid;

1613
	ad.type = LSM_AUDIT_DATA_DENTRY;
1614
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1615

1616
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1617 1618 1619 1620 1621
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1622
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1623 1624
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1625 1626 1627 1628
		if (rc)
			return rc;
	}

1629
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1630 1631 1632 1633 1634 1635 1636 1637
	if (rc)
		return rc;

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

1638 1639 1640 1641
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1642
	u32 sid = task_sid(ctx);
1643

1644
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1645 1646
}

1647 1648 1649
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1650 1651 1652 1653 1654 1655 1656 1657

/* 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;
1658
	struct common_audit_data ad;
1659
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1660 1661 1662 1663 1664 1665
	u32 av;
	int rc;

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

1666
	ad.type = LSM_AUDIT_DATA_DENTRY;
1667
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1668 1669 1670

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1671
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685
	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
1686 1687
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1688 1689 1690
		return 0;
	}

1691
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1692 1693 1694 1695 1696 1697 1698 1699 1700
	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;
1701
	struct common_audit_data ad;
1702
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1703 1704 1705 1706 1707 1708 1709 1710 1711
	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;

1712
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1713

1714
	ad.u.dentry = old_dentry;
1715
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1716 1717 1718
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1719
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1720 1721 1722 1723
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1724
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1725 1726 1727 1728 1729
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1730
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1731 1732 1733
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1734
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1735 1736 1737 1738 1739
	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);
1740
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1741 1742 1743 1744 1745 1746 1747 1748 1749 1750
				  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. */
1751
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1752 1753
			       struct super_block *sb,
			       u32 perms,
1754
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1755 1756
{
	struct superblock_security_struct *sbsec;
1757
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1758 1759

	sbsec = sb->s_security;
1760
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1761 1762 1763 1764 1765 1766 1767
}

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

A
Al Viro 已提交
1768
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790
		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;
}

1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813
/* 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
1814
/*
1815
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1816 1817
 * open permission.
 */
1818
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1819
{
1820
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1821

1822 1823 1824
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1825 1826 1827
	return av;
}

L
Linus Torvalds 已提交
1828 1829
/* Hook functions begin here. */

1830
static int selinux_ptrace_access_check(struct task_struct *child,
1831
				     unsigned int mode)
L
Linus Torvalds 已提交
1832 1833 1834
{
	int rc;

1835
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1836 1837 1838
	if (rc)
		return rc;

1839
	if (mode & PTRACE_MODE_READ) {
1840 1841 1842
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1843 1844
	}

1845
	return current_has_perm(child, PROCESS__PTRACE);
1846 1847 1848 1849 1850 1851
}

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

1852
	rc = cap_ptrace_traceme(parent);
1853 1854 1855 1856
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1857 1858 1859
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1860
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1861 1862 1863
{
	int error;

1864
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1865 1866 1867
	if (error)
		return error;

1868
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1869 1870
}

D
David Howells 已提交
1871 1872 1873 1874
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
1875 1876 1877
{
	int error;

1878
	error = cap_capset(new, old,
D
David Howells 已提交
1879
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1880 1881 1882
	if (error)
		return error;

D
David Howells 已提交
1883
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1884 1885
}

1886 1887 1888 1889 1890 1891 1892 1893 1894 1895
/*
 * (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.
 */

1896 1897
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1898 1899 1900
{
	int rc;

1901
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1902 1903 1904
	if (rc)
		return rc;

1905
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1906 1907 1908 1909
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1910
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1911 1912 1913 1914 1915 1916
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1917 1918 1919 1920 1921
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1922
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1923 1924 1925 1926
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1927
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1928 1929 1930 1931
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1932 1933 1934 1935 1936 1937
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1938 1939
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1940
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1941 1942
}

1943
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1944 1945 1946 1947
{
	int rc;

	switch (type) {
1948 1949
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1950 1951
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1952 1953 1954 1955
	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
	/* Set level of messages printed to console */
	case SYSLOG_ACTION_CONSOLE_LEVEL:
1956 1957
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1958 1959 1960 1961 1962
	case SYSLOG_ACTION_CLOSE:	/* Close log */
	case SYSLOG_ACTION_OPEN:	/* Open log */
	case SYSLOG_ACTION_READ:	/* Read from log */
	case SYSLOG_ACTION_READ_CLEAR:	/* Read/clear last kernel messages */
	case SYSLOG_ACTION_CLEAR:	/* Clear ring buffer */
1963 1964 1965
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977
	}
	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.
 */
1978
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1979 1980 1981
{
	int rc, cap_sys_admin = 0;

1982
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1983
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1984 1985 1986
	if (rc == 0)
		cap_sys_admin = 1;

1987
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1988 1989 1990 1991
}

/* binprm security operations */

1992
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1993
{
1994 1995
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1996
	struct inode_security_struct *isec;
1997
	struct common_audit_data ad;
A
Al Viro 已提交
1998
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
1999 2000
	int rc;

2001
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2002 2003 2004
	if (rc)
		return rc;

2005 2006 2007
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2008 2009
		return 0;

2010 2011
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2012 2013 2014
	isec = inode->i_security;

	/* Default to the current task SID. */
2015 2016
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2017

2018
	/* Reset fs, key, and sock SIDs on execve. */
2019 2020 2021
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2022

2023 2024
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2025
		/* Reset exec SID on execve. */
2026
		new_tsec->exec_sid = 0;
2027 2028 2029 2030 2031 2032 2033

		/*
		 * Minimize confusion: if no_new_privs and a transition is
		 * explicitly requested, then fail the exec.
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
L
Linus Torvalds 已提交
2034 2035
	} else {
		/* Check for a default transition on this program. */
2036
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2037 2038
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2039 2040 2041 2042
		if (rc)
			return rc;
	}

2043
	ad.type = LSM_AUDIT_DATA_PATH;
2044
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2045

2046 2047
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2048
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2049

2050 2051
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2052 2053 2054 2055 2056
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2057
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2058 2059 2060 2061
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2062
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2063 2064 2065 2066
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084
		/* 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();
2085
			tracer = ptrace_parent(current);
2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099
			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
2100

2101 2102
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2103 2104 2105 2106 2107
	}

	return 0;
}

2108
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2109
{
2110
	const struct task_security_struct *tsec = current_security();
2111
	u32 sid, osid;
L
Linus Torvalds 已提交
2112 2113
	int atsecure = 0;

2114 2115 2116 2117
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2118 2119 2120
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2121
		atsecure = avc_has_perm(osid, sid,
2122 2123
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2124 2125
	}

2126
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2127 2128
}

A
Al Viro 已提交
2129 2130 2131 2132 2133
static int match_file(const void *p, struct file *file, unsigned fd)
{
	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
}

L
Linus Torvalds 已提交
2134
/* Derived from fs/exec.c:flush_old_files. */
2135 2136
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2137 2138
{
	struct file *file, *devnull = NULL;
2139
	struct tty_struct *tty;
2140
	int drop_tty = 0;
A
Al Viro 已提交
2141
	unsigned n;
L
Linus Torvalds 已提交
2142

2143
	tty = get_current_tty();
L
Linus Torvalds 已提交
2144
	if (tty) {
N
Nick Piggin 已提交
2145
		spin_lock(&tty_files_lock);
2146
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2147
			struct tty_file_private *file_priv;
2148

L
Linus Torvalds 已提交
2149
			/* Revalidate access to controlling tty.
2150
			   Use path_has_perm on the tty path directly rather
L
Linus Torvalds 已提交
2151 2152 2153
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
N
Nick Piggin 已提交
2154 2155 2156
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2157
			if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2158
				drop_tty = 1;
L
Linus Torvalds 已提交
2159
		}
N
Nick Piggin 已提交
2160
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2161
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2162
	}
2163 2164 2165
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2166 2167

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2168 2169 2170
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2171

A
Al Viro 已提交
2172
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2173 2174 2175 2176 2177 2178 2179
	if (IS_ERR(devnull))
		devnull = NULL;
	/* replace all the matching ones with this */
	do {
		replace_fd(n - 1, devnull, 0);
	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
	if (devnull)
A
Al Viro 已提交
2180
		fput(devnull);
L
Linus Torvalds 已提交
2181 2182
}

2183 2184 2185 2186
/*
 * 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
2187
{
2188 2189 2190
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2191

2192 2193 2194
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2195

2196 2197
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2198

2199 2200
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2201

2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214
	/* 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) {
2215 2216
		/* protect against do_prlimit() */
		task_lock(current);
2217 2218 2219 2220
		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
2221
		}
2222 2223
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2224 2225 2226 2227
	}
}

/*
2228 2229
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2230
 */
2231
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2232
{
2233
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2234
	struct itimerval itimer;
2235
	u32 osid, sid;
L
Linus Torvalds 已提交
2236 2237
	int rc, i;

2238 2239 2240 2241
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2242 2243
		return;

2244 2245 2246 2247 2248 2249 2250 2251
	/* 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
2252 2253 2254 2255 2256
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2257 2258 2259 2260 2261
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2262 2263 2264
		spin_unlock_irq(&current->sighand->siglock);
	}

2265 2266
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2267
	read_lock(&tasklist_lock);
2268
	__wake_up_parent(current, current->real_parent);
2269
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293
}

/* 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)
{
2294 2295 2296
	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) ||
2297 2298
		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
2299 2300 2301 2302 2303 2304 2305
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2306
	} else
L
Linus Torvalds 已提交
2307 2308 2309 2310 2311
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2312 2313
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2314 2315 2316 2317 2318 2319
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2320
	} else
2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332
		*first = 0;

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

2333
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2334 2335 2336 2337
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2338
	int open_quote = 0;
L
Linus Torvalds 已提交
2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353

	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 {
2354 2355 2356 2357
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2358 2359 2360
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2361
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2362 2363 2364 2365 2366 2367 2368
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2369
	strcpy(in_save, nosec_save);
2370
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2371 2372 2373 2374
out:
	return rc;
}

2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

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

	if (!data)
		return 0;

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

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

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

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

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

2410
		if (flags[i] == SBLABEL_MNT)
2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
			continue;
		len = strlen(mount_options[i]);
		rc = security_context_to_sid(mount_options[i], len, &sid);
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
			goto out_free_opts;
		}
		rc = -EINVAL;
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
				goto out_bad_option;
			break;
		case CONTEXT_MNT:
			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
				goto out_bad_option;
			break;
		case ROOTCONTEXT_MNT: {
			struct inode_security_struct *root_isec;
			root_isec = sb->s_root->d_inode->i_security;

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

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

2460
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2461
{
2462
	const struct cred *cred = current_cred();
2463
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2464 2465 2466 2467 2468 2469
	int rc;

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

2470 2471 2472 2473
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2474
	ad.type = LSM_AUDIT_DATA_DENTRY;
2475
	ad.u.dentry = sb->s_root;
2476
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2477 2478
}

2479
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2480
{
2481
	const struct cred *cred = current_cred();
2482
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2483

2484
	ad.type = LSM_AUDIT_DATA_DENTRY;
2485
	ad.u.dentry = dentry->d_sb->s_root;
2486
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2487 2488
}

A
Al Viro 已提交
2489
static int selinux_mount(const char *dev_name,
2490
			 struct path *path,
A
Al Viro 已提交
2491
			 const char *type,
2492 2493
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2494
{
2495
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2496 2497

	if (flags & MS_REMOUNT)
2498
		return superblock_has_perm(cred, path->dentry->d_sb,
2499
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2500
	else
E
Eric Paris 已提交
2501
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2502 2503 2504 2505
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2506
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2507

2508
	return superblock_has_perm(cred, mnt->mnt_sb,
2509
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523
}

/* 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);
}

2524
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2525 2526
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2527
{
2528
	const struct task_security_struct *tsec = current_security();
2529 2530
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2531
	u32 sid, newsid, clen;
2532
	int rc;
2533
	char *namep = NULL, *context;
2534 2535 2536 2537

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

2538 2539 2540
	sid = tsec->sid;
	newsid = tsec->create_sid;

2541 2542 2543
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2544
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2545
		rc = security_transition_sid(sid, dsec->sid,
2546
					     inode_mode_to_security_class(inode->i_mode),
2547
					     qstr, &newsid);
2548 2549 2550 2551
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2552
			       __func__,
2553 2554 2555 2556 2557
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2558
	/* Possibly defer initialization to selinux_complete_init. */
2559
	if (sbsec->flags & SE_SBINITIALIZED) {
2560 2561 2562 2563 2564
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2565

2566
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2567 2568
		return -EOPNOTSUPP;

2569
	if (name) {
2570
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2571 2572 2573 2574
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2575

2576
	if (value && len) {
2577
		rc = security_sid_to_context_force(newsid, &context, &clen);
2578 2579 2580 2581 2582 2583
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2584 2585 2586 2587 2588
	}

	return 0;
}

A
Al Viro 已提交
2589
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608
{
	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);
}

2609
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2610 2611 2612 2613 2614 2615 2616 2617 2618
{
	return may_create(dir, dentry, SECCLASS_DIR);
}

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

A
Al Viro 已提交
2619
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2620 2621 2622 2623 2624
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2625
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2626 2627 2628 2629 2630 2631
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2632 2633
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2634
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2635 2636 2637 2638
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2639
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2640

E
Eric Paris 已提交
2641
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2642 2643
}

2644 2645 2646
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2647
{
2648
	struct common_audit_data ad;
2649 2650 2651
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2652
	ad.type = LSM_AUDIT_DATA_INODE;
2653 2654 2655 2656 2657 2658 2659 2660 2661
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
			    audited, denied, &ad, flags);
	if (rc)
		return rc;
	return 0;
}

2662
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2663
{
2664
	const struct cred *cred = current_cred();
2665 2666
	u32 perms;
	bool from_access;
2667
	unsigned flags = mask & MAY_NOT_BLOCK;
2668 2669 2670 2671 2672
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2673

2674
	from_access = mask & MAY_ACCESS;
2675 2676
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2677 2678
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2679 2680
		return 0;

2681
	validate_creds(cred);
2682

2683 2684
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2685 2686 2687

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

2688 2689 2690 2691 2692 2693 2694 2695 2696 2697
	sid = cred_sid(cred);
	isec = inode->i_security;

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

2698
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2699 2700 2701
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2702 2703 2704 2705
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2706
	const struct cred *cred = current_cred();
2707
	unsigned int ia_valid = iattr->ia_valid;
2708
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2709

2710 2711 2712 2713 2714 2715 2716
	/* 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
2717

2718 2719
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2720
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2721

2722
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2723 2724 2725
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2726 2727 2728 2729
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2730
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2731 2732 2733 2734
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2735

E
Eric Paris 已提交
2736
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2737 2738
}

2739
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2740
{
2741 2742
	const struct cred *cred = current_cred();

2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756
	if (!strncmp(name, XATTR_SECURITY_PREFIX,
		     sizeof XATTR_SECURITY_PREFIX - 1)) {
		if (!strcmp(name, XATTR_NAME_CAPS)) {
			if (!capable(CAP_SETFCAP))
				return -EPERM;
		} else if (!capable(CAP_SYS_ADMIN)) {
			/* A different attribute in the security namespace.
			   Restrict to administrator. */
			return -EPERM;
		}
	}

	/* Not an attribute we recognize, so just check the
	   ordinary setattr permission. */
E
Eric Paris 已提交
2757
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2758 2759
}

2760 2761
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
2762 2763 2764 2765
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2766
	struct common_audit_data ad;
2767
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2768 2769
	int rc = 0;

2770 2771
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2772 2773

	sbsec = inode->i_sb->s_security;
2774
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2775 2776
		return -EOPNOTSUPP;

2777
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2778 2779
		return -EPERM;

2780
	ad.type = LSM_AUDIT_DATA_DENTRY;
2781
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2782

2783
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2784 2785 2786 2787 2788
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2789
	if (rc == -EINVAL) {
2790 2791 2792 2793 2794 2795 2796
		if (!capable(CAP_MAC_ADMIN)) {
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
2797 2798 2799 2800 2801 2802 2803 2804 2805 2806
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2807 2808 2809 2810 2811
			ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
			audit_log_format(ab, "op=setxattr invalid_context=");
			audit_log_n_untrustedstring(ab, value, audit_size);
			audit_log_end(ab);

2812
			return rc;
2813
		}
2814 2815
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2816 2817 2818
	if (rc)
		return rc;

2819
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2820 2821 2822 2823
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2824
	rc = security_validate_transition(isec->sid, newsid, sid,
2825
					  isec->sclass);
L
Linus Torvalds 已提交
2826 2827 2828 2829 2830 2831 2832 2833 2834 2835
	if (rc)
		return rc;

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

2836
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2837
					const void *value, size_t size,
2838
					int flags)
L
Linus Torvalds 已提交
2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849
{
	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;
	}

2850
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2851
	if (rc) {
2852 2853 2854
		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
2855 2856 2857 2858 2859 2860 2861
		return;
	}

	isec->sid = newsid;
	return;
}

2862
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2863
{
2864 2865
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2866
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2867 2868
}

2869
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2870
{
2871 2872
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2873
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2874 2875
}

2876
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2877
{
2878 2879
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2880 2881 2882 2883 2884 2885

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

2886
/*
2887
 * Copy the inode security context value to the user.
2888 2889 2890
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2891
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2892
{
2893 2894 2895
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2896
	struct inode_security_struct *isec = inode->i_security;
2897

2898 2899
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2900

2901 2902 2903 2904 2905 2906 2907 2908 2909
	/*
	 * 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.
	 */
2910
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2911
				SECURITY_CAP_NOAUDIT);
2912 2913 2914 2915 2916
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2917 2918 2919 2920 2921 2922 2923 2924 2925 2926
	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
2927 2928 2929
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2930
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941
{
	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;

2942
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2943 2944 2945 2946
	if (rc)
		return rc;

	isec->sid = newsid;
2947
	isec->initialized = 1;
L
Linus Torvalds 已提交
2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958
	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;
}

2959 2960 2961 2962 2963 2964
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
2965 2966
/* file security operations */

2967
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2968
{
2969
	const struct cred *cred = current_cred();
A
Al Viro 已提交
2970
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
2971 2972 2973 2974 2975

	/* 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;

2976 2977
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2978 2979
}

2980 2981
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
2982
	struct inode *inode = file_inode(file);
2983 2984 2985 2986
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2987
	if (!mask)
2988 2989 2990
		/* No permission to check.  Existence test. */
		return 0;

2991 2992
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
2993
		/* No change since file_open check. */
2994 2995
		return 0;

2996 2997 2998
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011
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)
{
3012
	const struct cred *cred = current_cred();
3013
	int error = 0;
L
Linus Torvalds 已提交
3014

3015 3016 3017 3018 3019 3020 3021
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3022
	case FS_IOC_GETFLAGS:
3023
	/* fall through */
3024
	case FS_IOC_GETVERSION:
3025 3026
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3027

3028
	case FS_IOC_SETFLAGS:
3029
	/* fall through */
3030
	case FS_IOC_SETVERSION:
3031 3032 3033 3034 3035 3036 3037 3038 3039
		error = file_has_perm(cred, file, FILE__SETATTR);
		break;

	/* sys_ioctl() checks */
	case FIONBIO:
	/* fall through */
	case FIOASYNC:
		error = file_has_perm(cred, file, 0);
		break;
L
Linus Torvalds 已提交
3040

3041 3042
	case KDSKBENT:
	case KDSKBSENT:
3043 3044
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3045 3046 3047 3048 3049 3050 3051 3052 3053
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
		error = file_has_perm(cred, file, FILE__IOCTL);
	}
	return error;
L
Linus Torvalds 已提交
3054 3055
}

3056 3057
static int default_noexec;

L
Linus Torvalds 已提交
3058 3059
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3060
	const struct cred *cred = current_cred();
D
David Howells 已提交
3061
	int rc = 0;
3062

3063 3064
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3065 3066 3067 3068 3069
		/*
		 * 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
3070
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3071
		if (rc)
D
David Howells 已提交
3072
			goto error;
L
Linus Torvalds 已提交
3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085
	}

	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;

3086
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3087
	}
D
David Howells 已提交
3088 3089 3090

error:
	return rc;
L
Linus Torvalds 已提交
3091 3092
}

3093
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3094
{
3095
	int rc = 0;
3096
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3097

3098 3099 3100 3101 3102 3103
	/*
	 * 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.
	 */
3104
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3105 3106
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3107 3108 3109 3110 3111
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3112 3113
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3114

3115 3116 3117
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128
	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)
{
3129
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3130 3131 3132 3133

	if (selinux_checkreqprot)
		prot = reqprot;

3134 3135
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3136
		int rc = 0;
3137 3138
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3139
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3140 3141 3142
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3143
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3144 3145 3146 3147 3148 3149 3150 3151
		} 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
3152
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3153
		}
3154 3155 3156
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3157 3158 3159 3160 3161 3162

	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)
{
3163 3164 3165
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3166 3167 3168 3169 3170
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3171
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3172 3173 3174
	int err = 0;

	switch (cmd) {
3175 3176
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3177
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3178
			break;
3179 3180 3181 3182 3183 3184 3185
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3186
	case F_GETOWNER_UIDS:
3187
		/* Just check FD__USE permission */
3188
		err = file_has_perm(cred, file, 0);
3189 3190 3191 3192
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3193
#if BITS_PER_LONG == 32
3194 3195 3196
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3197
#endif
3198
		err = file_has_perm(cred, file, FILE__LOCK);
3199
		break;
L
Linus Torvalds 已提交
3200 3201 3202 3203 3204 3205 3206 3207 3208 3209
	}

	return err;
}

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

	fsec = file->f_security;
3210
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3211 3212 3213 3214 3215 3216 3217

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3218
	struct file *file;
3219
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3220 3221 3222 3223
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3224
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3225 3226 3227 3228 3229 3230 3231 3232

	fsec = file->f_security;

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

3233
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3234 3235 3236 3237 3238
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3239 3240 3241
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3242 3243
}

3244
static int selinux_file_open(struct file *file, const struct cred *cred)
3245 3246 3247
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3248

3249
	fsec = file->f_security;
A
Al Viro 已提交
3250
	isec = file_inode(file)->i_security;
3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267
	/*
	 * 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.
	 */
3268
	return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3269 3270
}

L
Linus Torvalds 已提交
3271 3272 3273 3274
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3275
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3276 3277
}

3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292
/*
 * 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
3293 3294 3295 3296
/*
 * 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
3297
{
D
David Howells 已提交
3298
	struct task_security_struct *tsec = cred->security;
3299

3300 3301 3302 3303 3304
	/*
	 * cred->security == NULL if security_cred_alloc_blank() or
	 * security_prepare_creds() returned an error.
	 */
	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3305
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3306 3307
	kfree(tsec);
}
L
Linus Torvalds 已提交
3308

D
David Howells 已提交
3309 3310 3311 3312 3313 3314 3315 3316
/*
 * 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
3317

D
David Howells 已提交
3318
	old_tsec = old->security;
L
Linus Torvalds 已提交
3319

D
David Howells 已提交
3320 3321 3322
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3323

D
David Howells 已提交
3324
	new->security = tsec;
L
Linus Torvalds 已提交
3325 3326 3327
	return 0;
}

3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338
/*
 * 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;
}

3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379
/*
 * 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;
3380
	return ret;
3381 3382
}

3383
static int selinux_kernel_module_request(char *kmod_name)
3384
{
3385 3386 3387 3388 3389
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3390
	ad.type = LSM_AUDIT_DATA_KMOD;
3391 3392 3393 3394
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3395 3396
}

L
Linus Torvalds 已提交
3397 3398
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3399
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3400 3401 3402 3403
}

static int selinux_task_getpgid(struct task_struct *p)
{
3404
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3405 3406 3407 3408
}

static int selinux_task_getsid(struct task_struct *p)
{
3409
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3410 3411
}

3412 3413
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3414
	*secid = task_sid(p);
3415 3416
}

L
Linus Torvalds 已提交
3417 3418 3419 3420
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3421
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3422 3423 3424
	if (rc)
		return rc;

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

3428 3429
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3430 3431
	int rc;

3432
	rc = cap_task_setioprio(p, ioprio);
3433 3434 3435
	if (rc)
		return rc;

3436
	return current_has_perm(p, PROCESS__SETSCHED);
3437 3438
}

3439 3440
static int selinux_task_getioprio(struct task_struct *p)
{
3441
	return current_has_perm(p, PROCESS__GETSCHED);
3442 3443
}

3444 3445
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3446
{
3447
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3448 3449 3450 3451

	/* 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
3452
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3453
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3454
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3455 3456 3457 3458

	return 0;
}

3459
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3460
{
3461 3462
	int rc;

3463
	rc = cap_task_setscheduler(p);
3464 3465 3466
	if (rc)
		return rc;

3467
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3468 3469 3470 3471
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3472
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3473 3474
}

3475 3476
static int selinux_task_movememory(struct task_struct *p)
{
3477
	return current_has_perm(p, PROCESS__SETSCHED);
3478 3479
}

3480 3481
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3482 3483 3484 3485 3486 3487 3488 3489
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3490
	if (secid)
3491 3492
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3493
	else
3494
		rc = current_has_perm(p, perm);
3495
	return rc;
L
Linus Torvalds 已提交
3496 3497 3498 3499
}

static int selinux_task_wait(struct task_struct *p)
{
3500
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3501 3502 3503 3504 3505 3506
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3507
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3508

3509
	isec->sid = sid;
L
Linus Torvalds 已提交
3510 3511 3512 3513
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3514
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3515
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3516 3517 3518 3519
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

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

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

3529 3530
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3531 3532
	ret = 0;

3533 3534 3535
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3536
	switch (ih->protocol) {
3537 3538
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3539

3540 3541
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3542 3543 3544 3545 3546 3547

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

3548 3549
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3550
		break;
3551 3552 3553 3554 3555 3556 3557 3558
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3559
		offset += ihlen;
3560
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3561
		if (uh == NULL)
3562
			break;
L
Linus Torvalds 已提交
3563

3564 3565
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3566 3567
		break;
	}
L
Linus Torvalds 已提交
3568

J
James Morris 已提交
3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579
	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;

3580 3581
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3582
		break;
3583
	}
J
James Morris 已提交
3584

3585 3586 3587
	default:
		break;
	}
L
Linus Torvalds 已提交
3588 3589 3590 3591 3592 3593 3594
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3595
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3596
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3597 3598 3599 3600
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3601
	__be16 frag_off;
L
Linus Torvalds 已提交
3602

3603
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3604 3605 3606 3607
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3608 3609
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3610 3611 3612 3613
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3614
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3615 3616 3617
	if (offset < 0)
		goto out;

3618 3619 3620
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3621 3622
	switch (nexthdr) {
	case IPPROTO_TCP: {
3623
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3624 3625 3626 3627 3628

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

3629 3630
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3631 3632 3633 3634 3635 3636 3637 3638 3639 3640
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3641 3642
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3643 3644 3645
		break;
	}

J
James Morris 已提交
3646 3647 3648 3649 3650 3651 3652
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3653 3654
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3655
		break;
3656
	}
J
James Morris 已提交
3657

L
Linus Torvalds 已提交
3658 3659 3660 3661 3662 3663 3664 3665 3666 3667
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3668
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3669
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3670
{
3671 3672
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3673

3674
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3675
	case PF_INET:
3676
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3677 3678
		if (ret)
			goto parse_error;
3679 3680
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3681
		goto okay;
L
Linus Torvalds 已提交
3682 3683 3684

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3685
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3686 3687
		if (ret)
			goto parse_error;
3688 3689
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3690
		goto okay;
L
Linus Torvalds 已提交
3691 3692
#endif	/* IPV6 */
	default:
3693 3694
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3695 3696
	}

3697 3698 3699 3700
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3701
	return ret;
3702 3703 3704 3705 3706

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3707 3708
}

3709
/**
3710
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3711
 * @skb: the packet
3712
 * @family: protocol family
3713
 * @sid: the packet's peer label SID
3714 3715
 *
 * Description:
3716 3717 3718 3719 3720 3721
 * 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.
3722 3723
 *
 */
3724
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3725
{
3726
	int err;
3727 3728
	u32 xfrm_sid;
	u32 nlbl_sid;
3729
	u32 nlbl_type;
3730

3731 3732 3733 3734 3735 3736
	err = selinux_skb_xfrm_sid(skb, &xfrm_sid);
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3737

3738 3739 3740 3741 3742
	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");
3743
		return -EACCES;
3744
	}
3745 3746

	return 0;
3747 3748
}

L
Linus Torvalds 已提交
3749
/* socket security operations */
3750

3751 3752
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3753
{
3754 3755 3756 3757 3758 3759 3760
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3761 3762
}

3763
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3764
{
3765
	struct sk_security_struct *sksec = sk->sk_security;
3766
	struct common_audit_data ad;
3767
	struct lsm_network_audit net = {0,};
3768
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3769

3770 3771
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3772

3773
	ad.type = LSM_AUDIT_DATA_NET;
3774 3775
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3776

3777
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3778 3779 3780 3781 3782
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3783
	const struct task_security_struct *tsec = current_security();
3784
	u32 newsid;
3785
	u16 secclass;
3786
	int rc;
L
Linus Torvalds 已提交
3787 3788

	if (kern)
3789
		return 0;
3790 3791

	secclass = socket_type_to_security_class(family, type, protocol);
3792 3793 3794 3795
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3796
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3797 3798
}

V
Venkat Yekkirala 已提交
3799 3800
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3801
{
3802
	const struct task_security_struct *tsec = current_security();
3803
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3804
	struct sk_security_struct *sksec;
3805 3806
	int err = 0;

3807 3808
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3809 3810
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3811 3812 3813 3814 3815
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3816

L
Linus Torvalds 已提交
3817 3818
	isec->initialized = 1;

3819 3820 3821
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3822
		sksec->sclass = isec->sclass;
3823
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3824 3825
	}

V
Venkat Yekkirala 已提交
3826
	return err;
L
Linus Torvalds 已提交
3827 3828 3829 3830 3831 3832 3833 3834
}

/* 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)
{
3835
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3836 3837 3838
	u16 family;
	int err;

3839
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3840 3841 3842 3843 3844
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3845 3846
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3847
	 */
3848
	family = sk->sk_family;
L
Linus Torvalds 已提交
3849 3850
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3851
		struct sk_security_struct *sksec = sk->sk_security;
3852
		struct common_audit_data ad;
3853
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3854 3855 3856
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3857
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868

		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;
		}

3869 3870 3871 3872 3873 3874
		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
3875 3876
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3877 3878
				if (err)
					goto out;
3879
				ad.type = LSM_AUDIT_DATA_NET;
3880 3881 3882
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
3883 3884
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3885 3886 3887 3888
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3889
		}
3890

3891
		switch (sksec->sclass) {
3892
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3893 3894
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3895

3896
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3897 3898
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3899 3900 3901 3902 3903

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3904 3905 3906 3907
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3908

3909
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3910 3911
		if (err)
			goto out;
3912

3913
		ad.type = LSM_AUDIT_DATA_NET;
3914 3915 3916
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
3917 3918

		if (family == PF_INET)
3919
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
3920
		else
3921
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3922

3923 3924
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3925 3926 3927 3928 3929 3930 3931 3932 3933
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3934
	struct sock *sk = sock->sk;
3935
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3936 3937
	int err;

3938
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3939 3940 3941 3942
	if (err)
		return err;

	/*
J
James Morris 已提交
3943
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3944
	 */
3945 3946
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3947
		struct common_audit_data ad;
3948
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3949 3950 3951
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3952
		u32 sid, perm;
L
Linus Torvalds 已提交
3953 3954 3955

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3956
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3957 3958 3959 3960
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3961
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3962 3963 3964 3965
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3966
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3967 3968 3969
		if (err)
			goto out;

3970
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3971 3972
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3973
		ad.type = LSM_AUDIT_DATA_NET;
3974 3975 3976
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
3977
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3978 3979 3980 3981
		if (err)
			goto out;
	}

3982 3983
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3984 3985 3986 3987 3988 3989
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3990
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3991 3992 3993 3994 3995 3996 3997 3998
}

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

3999
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013
	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,
4014
				  int size)
L
Linus Torvalds 已提交
4015
{
4016
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4017 4018 4019 4020 4021
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4022
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4023 4024 4025 4026
}

static int selinux_socket_getsockname(struct socket *sock)
{
4027
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4028 4029 4030 4031
}

static int selinux_socket_getpeername(struct socket *sock)
{
4032
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4033 4034
}

4035
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4036
{
4037 4038
	int err;

4039
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4040 4041 4042 4043
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4044 4045 4046 4047 4048
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4049
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4050 4051 4052 4053
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4054
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4055 4056
}

4057 4058
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4059 4060
					      struct sock *newsk)
{
4061 4062
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4063
	struct sk_security_struct *sksec_new = newsk->sk_security;
4064
	struct common_audit_data ad;
4065
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4066 4067
	int err;

4068
	ad.type = LSM_AUDIT_DATA_NET;
4069 4070
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4071

4072 4073
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4074 4075 4076 4077 4078
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4079 4080 4081 4082 4083
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4084

4085 4086 4087 4088
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4089 4090 4091 4092 4093
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4094 4095
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4096
	struct common_audit_data ad;
4097
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4098

4099
	ad.type = LSM_AUDIT_DATA_NET;
4100 4101
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4102

4103 4104
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4105 4106
}

4107 4108
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4109
				    struct common_audit_data *ad)
4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129
{
	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);
}

4130
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4131
				       u16 family)
4132
{
4133
	int err = 0;
4134 4135
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4136
	struct common_audit_data ad;
4137
	struct lsm_network_audit net = {0,};
4138 4139
	char *addrp;

4140
	ad.type = LSM_AUDIT_DATA_NET;
4141 4142 4143
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4144 4145 4146
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4147

4148
	if (selinux_secmark_enabled()) {
4149
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4150
				   PACKET__RECV, &ad);
4151 4152 4153
		if (err)
			return err;
	}
4154

4155 4156 4157 4158
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4159

4160 4161 4162 4163 4164
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4165
	int err;
4166
	struct sk_security_struct *sksec = sk->sk_security;
4167 4168
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4169
	struct common_audit_data ad;
4170
	struct lsm_network_audit net = {0,};
4171
	char *addrp;
4172 4173
	u8 secmark_active;
	u8 peerlbl_active;
4174 4175

	if (family != PF_INET && family != PF_INET6)
4176
		return 0;
4177 4178

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4179
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4180 4181
		family = PF_INET;

4182 4183 4184 4185
	/* 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. */
4186
	if (!selinux_policycap_netpeer)
4187 4188 4189 4190 4191 4192 4193
		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;

4194
	ad.type = LSM_AUDIT_DATA_NET;
4195 4196 4197
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4198
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4199
	if (err)
4200
		return err;
4201

4202
	if (peerlbl_active) {
4203 4204 4205
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4206 4207
		if (err)
			return err;
4208
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4209
					       peer_sid, &ad);
4210 4211
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4212
			return err;
4213
		}
4214 4215
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4216 4217
		if (err)
			selinux_netlbl_err(skb, err, 0);
4218 4219
	}

4220
	if (secmark_active) {
4221 4222 4223 4224 4225 4226
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4227
	return err;
L
Linus Torvalds 已提交
4228 4229
}

C
Catherine Zhang 已提交
4230 4231
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4232 4233 4234 4235
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4236
	struct sk_security_struct *sksec = sock->sk->sk_security;
4237
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4238

4239 4240
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4241
		peer_sid = sksec->peer_sid;
4242 4243
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4244

C
Catherine Zhang 已提交
4245
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4246
	if (err)
4247
		return err;
L
Linus Torvalds 已提交
4248 4249 4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263

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

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

out_len:
	if (put_user(scontext_len, optlen))
		err = -EFAULT;
	kfree(scontext);
	return err;
}

4264
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4265
{
4266
	u32 peer_secid = SECSID_NULL;
4267
	u16 family;
C
Catherine Zhang 已提交
4268

4269 4270 4271 4272 4273
	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)
4274 4275 4276 4277 4278
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4279
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4280
	else if (skb)
4281
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4282

4283
out:
4284
	*secid = peer_secid;
4285 4286 4287
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4288 4289
}

A
Al Viro 已提交
4290
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4291
{
4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303
	struct sk_security_struct *sksec;

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

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4304 4305 4306 4307
}

static void selinux_sk_free_security(struct sock *sk)
{
4308 4309 4310 4311 4312
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4313 4314
}

4315
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4316
{
4317 4318
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4319

4320 4321 4322
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4323

4324
	selinux_netlbl_sk_security_reset(newsksec);
4325 4326
}

V
Venkat Yekkirala 已提交
4327
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4328
{
4329
	if (!sk)
V
Venkat Yekkirala 已提交
4330
		*secid = SECINITSID_ANY_SOCKET;
4331 4332
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4333

V
Venkat Yekkirala 已提交
4334
		*secid = sksec->sid;
4335
	}
4336 4337
}

4338
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4339 4340 4341 4342
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4343 4344 4345
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4346
	sksec->sclass = isec->sclass;
4347 4348
}

4349 4350
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4351 4352 4353
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4354
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4355
	u32 newsid;
4356 4357
	u32 peersid;

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;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4363 4364
	if (err)
		return err;
4365 4366
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4367
		req->peer_secid = SECSID_NULL;
4368 4369 4370 4371 4372 4373
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4374 4375
	}

4376
	return selinux_netlbl_inet_conn_request(req, family);
4377 4378
}

4379 4380
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4381 4382 4383 4384
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4385
	newsksec->peer_sid = req->peer_secid;
4386 4387 4388 4389
	/* 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. */
4390

P
Paul Moore 已提交
4391 4392
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4393
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4394 4395
}

4396
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4397
{
4398
	u16 family = sk->sk_family;
4399 4400
	struct sk_security_struct *sksec = sk->sk_security;

4401 4402 4403 4404 4405
	/* 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);
4406 4407
}

4408 4409 4410 4411 4412
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433
static int selinux_secmark_relabel_packet(u32 sid)
{
	const struct task_security_struct *__tsec;
	u32 tsid;

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

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

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

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

4434 4435
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4436
{
4437
	fl->flowi_secid = req->secid;
4438 4439
}

4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457
static int selinux_tun_dev_alloc_security(void **security)
{
	struct tun_security_struct *tunsec;

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

	*security = tunsec;
	return 0;
}

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

4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472
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);
}

4473
static int selinux_tun_dev_attach_queue(void *security)
4474
{
4475 4476 4477 4478 4479 4480 4481 4482 4483
	struct tun_security_struct *tunsec = security;

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

static int selinux_tun_dev_attach(struct sock *sk, void *security)
{
	struct tun_security_struct *tunsec = security;
4484 4485 4486 4487 4488 4489 4490 4491 4492
	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 */

4493
	sksec->sid = tunsec->sid;
4494
	sksec->sclass = SECCLASS_TUN_SOCKET;
4495 4496

	return 0;
4497 4498
}

4499
static int selinux_tun_dev_open(void *security)
4500
{
4501
	struct tun_security_struct *tunsec = security;
4502 4503 4504
	u32 sid = current_sid();
	int err;

4505
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4506 4507 4508 4509 4510 4511 4512
			   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;
4513
	tunsec->sid = sid;
4514 4515 4516 4517

	return 0;
}

L
Linus Torvalds 已提交
4518 4519 4520 4521 4522
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4523
	struct sk_security_struct *sksec = sk->sk_security;
4524

4525
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4526 4527 4528
		err = -EINVAL;
		goto out;
	}
4529
	nlh = nlmsg_hdr(skb);
4530

4531
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4532 4533
	if (err) {
		if (err == -EINVAL) {
4534
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4535 4536
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4537
				  nlh->nlmsg_type, sksec->sclass);
4538
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4539 4540 4541 4542 4543 4544 4545 4546 4547
				err = 0;
		}

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

4548
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4549 4550 4551 4552 4553 4554
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4555 4556
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4557
{
4558
	int err;
4559 4560
	char *addrp;
	u32 peer_sid;
4561
	struct common_audit_data ad;
4562
	struct lsm_network_audit net = {0,};
4563
	u8 secmark_active;
4564
	u8 netlbl_active;
4565
	u8 peerlbl_active;
4566

4567 4568
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4569

4570
	secmark_active = selinux_secmark_enabled();
4571 4572
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4573 4574
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4575

4576 4577 4578
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4579
	ad.type = LSM_AUDIT_DATA_NET;
4580 4581 4582
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4583 4584 4585
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4586 4587 4588 4589 4590
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4591
			return NF_DROP;
4592 4593
		}
	}
4594 4595 4596 4597 4598 4599

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

4600 4601 4602 4603 4604 4605 4606 4607
	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;

4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630
	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 */

4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661
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);
}

4662 4663
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4664
						u16 family)
4665 4666 4667
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4668
	struct common_audit_data ad;
4669
	struct lsm_network_audit net = {0,};
4670 4671
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4672

4673 4674 4675 4676
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4677
	ad.type = LSM_AUDIT_DATA_NET;
4678 4679 4680
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4681 4682 4683
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4684
	if (selinux_secmark_enabled())
4685
		if (avc_has_perm(sksec->sid, skb->secmark,
4686
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4687
			return NF_DROP_ERR(-ECONNREFUSED);
4688

4689 4690
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4691 4692

	return NF_ACCEPT;
4693 4694
}

4695 4696
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4697
{
4698 4699
	u32 secmark_perm;
	u32 peer_sid;
4700
	struct sock *sk;
4701
	struct common_audit_data ad;
4702
	struct lsm_network_audit net = {0,};
4703 4704 4705
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4706

4707 4708 4709 4710
	/* 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. */
4711
	if (!selinux_policycap_netpeer)
4712
		return selinux_ip_postroute_compat(skb, ifindex, family);
4713
#ifdef CONFIG_XFRM
4714 4715 4716 4717 4718 4719
	/* 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
4720
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4721
		return NF_ACCEPT;
4722
#endif
4723 4724 4725 4726 4727
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4728 4729 4730 4731
	/* 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 */
4732
	sk = skb->sk;
4733
	if (sk == NULL) {
4734 4735
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4736
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4737
				return NF_DROP;
4738 4739
		} else {
			secmark_perm = PACKET__SEND;
4740
			peer_sid = SECINITSID_KERNEL;
4741
		}
4742
	} else {
4743 4744 4745 4746
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4747

4748
	ad.type = LSM_AUDIT_DATA_NET;
4749 4750 4751
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4752
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4753
		return NF_DROP;
4754

4755 4756 4757
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4758
			return NF_DROP_ERR(-ECONNREFUSED);
4759 4760 4761 4762 4763 4764

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4765
			return NF_DROP;
4766 4767
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4768
			return NF_DROP_ERR(-ECONNREFUSED);
4769 4770

		if (sel_netnode_sid(addrp, family, &node_sid))
4771
			return NF_DROP;
4772 4773
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4774
			return NF_DROP_ERR(-ECONNREFUSED);
4775
	}
4776

4777
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4778 4779
}

4780 4781 4782 4783 4784
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
4785
{
4786
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4787 4788 4789
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4790 4791 4792 4793 4794
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
4795
{
4796
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4797 4798 4799 4800 4801 4802 4803 4804 4805
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4806
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4807 4808 4809
	if (err)
		return err;

4810
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4811 4812 4813 4814 4815 4816 4817
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4818
	u32 sid;
L
Linus Torvalds 已提交
4819

J
James Morris 已提交
4820
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4821 4822 4823
	if (!isec)
		return -ENOMEM;

4824
	sid = task_sid(task);
L
Linus Torvalds 已提交
4825
	isec->sclass = sclass;
4826
	isec->sid = sid;
L
Linus Torvalds 已提交
4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842
	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
4843
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861
	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,
4862
			u32 perms)
L
Linus Torvalds 已提交
4863 4864
{
	struct ipc_security_struct *isec;
4865
	struct common_audit_data ad;
4866
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4867 4868 4869

	isec = ipc_perms->security;

4870
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4871 4872
	ad.u.ipc_id = ipc_perms->key;

4873
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889
}

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;
4890
	struct common_audit_data ad;
4891
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4892 4893 4894 4895 4896 4897 4898 4899
	int rc;

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

	isec = msq->q_perm.security;

4900
	ad.type = LSM_AUDIT_DATA_IPC;
4901
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4902

4903
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919
			  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;
4920
	struct common_audit_data ad;
4921
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4922 4923 4924

	isec = msq->q_perm.security;

4925
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4926 4927
	ad.u.ipc_id = msq->q_perm.key;

4928
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4929 4930 4931 4932 4933 4934 4935 4936
			    MSGQ__ASSOCIATE, &ad);
}

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

4937
	switch (cmd) {
L
Linus Torvalds 已提交
4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955
	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;
	}

4956
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4957 4958 4959 4960 4961 4962 4963
	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;
4964
	struct common_audit_data ad;
4965
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978
	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
		 */
4979
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4980
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4981 4982 4983 4984
		if (rc)
			return rc;
	}

4985
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4986 4987 4988
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4989
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4990 4991 4992
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4993 4994
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4995 4996
	if (!rc)
		/* Can the message be put in the queue? */
4997 4998
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4999 5000 5001 5002 5003 5004 5005 5006 5007 5008

	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;
5009
	struct common_audit_data ad;
5010
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5011 5012 5013 5014 5015
	int rc;

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

5016
	ad.type = LSM_AUDIT_DATA_IPC;
5017
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5018

5019
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5020 5021
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5022
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5023 5024 5025 5026 5027 5028 5029 5030
				  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;
5031
	struct common_audit_data ad;
5032
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5033 5034 5035 5036 5037 5038 5039 5040
	int rc;

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

	isec = shp->shm_perm.security;

5041
	ad.type = LSM_AUDIT_DATA_IPC;
5042
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5043

5044
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060
			  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;
5061
	struct common_audit_data ad;
5062
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5063 5064 5065

	isec = shp->shm_perm.security;

5066
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5067 5068
	ad.u.ipc_id = shp->shm_perm.key;

5069
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5070 5071 5072 5073 5074 5075 5076 5077 5078
			    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;

5079
	switch (cmd) {
L
Linus Torvalds 已提交
5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101
	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;
	}

5102
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115
	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;

5116
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5117 5118 5119 5120 5121 5122
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5123
	struct common_audit_data ad;
5124
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5125 5126 5127 5128 5129 5130 5131 5132
	int rc;

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

	isec = sma->sem_perm.security;

5133
	ad.type = LSM_AUDIT_DATA_IPC;
5134
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5135

5136
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152
			  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;
5153
	struct common_audit_data ad;
5154
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5155 5156 5157

	isec = sma->sem_perm.security;

5158
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5159 5160
	ad.u.ipc_id = sma->sem_perm.key;

5161
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5162 5163 5164 5165 5166 5167 5168 5169 5170
			    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;

5171
	switch (cmd) {
L
Linus Torvalds 已提交
5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201 5202
	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;
	}

5203
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216
	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;

5217
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232
}

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;

5233
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5234 5235
}

5236 5237 5238 5239 5240 5241
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5242
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5243 5244 5245 5246 5247 5248
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5249
			       char *name, char **value)
L
Linus Torvalds 已提交
5250
{
5251
	const struct task_security_struct *__tsec;
5252
	u32 sid;
L
Linus Torvalds 已提交
5253
	int error;
5254
	unsigned len;
L
Linus Torvalds 已提交
5255 5256

	if (current != p) {
5257
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5258 5259 5260 5261
		if (error)
			return error;
	}

5262 5263
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5264 5265

	if (!strcmp(name, "current"))
5266
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5267
	else if (!strcmp(name, "prev"))
5268
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5269
	else if (!strcmp(name, "exec"))
5270
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5271
	else if (!strcmp(name, "fscreate"))
5272
		sid = __tsec->create_sid;
5273
	else if (!strcmp(name, "keycreate"))
5274
		sid = __tsec->keycreate_sid;
5275
	else if (!strcmp(name, "sockcreate"))
5276
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5277
	else
5278 5279
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5280 5281 5282 5283

	if (!sid)
		return 0;

5284 5285 5286 5287
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5288 5289 5290 5291

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5292 5293 5294 5295 5296 5297
}

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
5298
	struct task_struct *tracer;
D
David Howells 已提交
5299 5300
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315
	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"))
5316
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5317
	else if (!strcmp(name, "fscreate"))
5318
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5319
	else if (!strcmp(name, "keycreate"))
5320
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5321
	else if (!strcmp(name, "sockcreate"))
5322
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5323
	else if (!strcmp(name, "current"))
5324
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336
	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);
5337
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352
			if (!capable(CAP_MAC_ADMIN)) {
				struct audit_buffer *ab;
				size_t audit_size;

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

5353
				return error;
5354
			}
5355 5356 5357
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5358 5359 5360 5361
		if (error)
			return error;
	}

D
David Howells 已提交
5362 5363 5364 5365
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5366 5367 5368
	/* 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
5369
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5370 5371
	   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
5372 5373
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5374
		tsec->exec_sid = sid;
D
David Howells 已提交
5375
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5376
		tsec->create_sid = sid;
D
David Howells 已提交
5377
	} else if (!strcmp(name, "keycreate")) {
5378 5379
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5380
			goto abort_change;
5381
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5382
	} else if (!strcmp(name, "sockcreate")) {
5383
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5384 5385
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5386
		if (sid == 0)
D
David Howells 已提交
5387 5388 5389 5390
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5391
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5392 5393 5394
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5395
		}
L
Linus Torvalds 已提交
5396 5397 5398

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5399
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5400
		if (error)
D
David Howells 已提交
5401
			goto abort_change;
L
Linus Torvalds 已提交
5402 5403 5404

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5405
		ptsid = 0;
L
Linus Torvalds 已提交
5406
		task_lock(p);
5407
		tracer = ptrace_parent(p);
D
David Howells 已提交
5408 5409 5410 5411 5412 5413 5414
		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
5415
			if (error)
D
David Howells 已提交
5416
				goto abort_change;
L
Linus Torvalds 已提交
5417 5418
		}

D
David Howells 已提交
5419 5420 5421 5422 5423 5424 5425
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5426
	return size;
D
David Howells 已提交
5427 5428 5429 5430

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5431 5432
}

5433 5434 5435 5436 5437
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5438
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5439 5440 5441 5442
{
	return security_context_to_sid(secdata, seclen, secid);
}

5443 5444
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5445
	kfree(secdata);
5446 5447
}

5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473
/*
 *	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;
}
5474 5475
#ifdef CONFIG_KEYS

D
David Howells 已提交
5476
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5477
			     unsigned long flags)
5478
{
D
David Howells 已提交
5479
	const struct task_security_struct *tsec;
5480 5481 5482 5483 5484 5485
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5486 5487 5488
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5489
	else
D
David Howells 已提交
5490
		ksec->sid = tsec->sid;
5491

5492
	k->security = ksec;
5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504
	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
5505 5506
				  const struct cred *cred,
				  key_perm_t perm)
5507 5508 5509
{
	struct key *key;
	struct key_security_struct *ksec;
5510
	u32 sid;
5511 5512 5513 5514 5515 5516 5517

	/* 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
5518
	sid = cred_sid(cred);
5519 5520 5521 5522 5523

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5524 5525
}

5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539
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;
}

5540 5541
#endif

L
Linus Torvalds 已提交
5542
static struct security_operations selinux_ops = {
5543 5544
	.name =				"selinux",

5545
	.ptrace_access_check =		selinux_ptrace_access_check,
5546
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5547
	.capget =			selinux_capget,
D
David Howells 已提交
5548
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5549 5550 5551 5552 5553 5554 5555 5556
	.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,

5557 5558 5559
	.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
5560 5561 5562 5563 5564
	.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,
5565
	.sb_remount =			selinux_sb_remount,
5566
	.sb_kern_mount =		selinux_sb_kern_mount,
5567
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5568 5569 5570
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5571
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5572
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5573 5574
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5575 5576 5577

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5578
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596
	.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,
5597 5598 5599
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5600
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5601 5602 5603 5604 5605

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5606 5607
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5608 5609 5610 5611 5612 5613 5614
	.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,

5615
	.file_open =			selinux_file_open,
5616

L
Linus Torvalds 已提交
5617
	.task_create =			selinux_task_create,
5618
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5619
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5620
	.cred_prepare =			selinux_cred_prepare,
5621
	.cred_transfer =		selinux_cred_transfer,
5622 5623
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5624
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5625 5626
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5627
	.task_getsid =			selinux_task_getsid,
5628
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5629
	.task_setnice =			selinux_task_setnice,
5630
	.task_setioprio =		selinux_task_setioprio,
5631
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5632 5633 5634
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5635
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5636 5637
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5638
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5639 5640

	.ipc_permission =		selinux_ipc_permission,
5641
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658

	.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,

5659 5660
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5661 5662 5663 5664
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5665
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5666

5667 5668
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5669

5670
	.secid_to_secctx =		selinux_secid_to_secctx,
5671
	.secctx_to_secid =		selinux_secctx_to_secid,
5672
	.release_secctx =		selinux_release_secctx,
5673 5674 5675
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5676

5677
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693
	.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
5694 5695
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5696 5697
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5698
	.sk_clone_security =		selinux_sk_clone_security,
5699
	.sk_getsecid =			selinux_sk_getsecid,
5700 5701 5702
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5703
	.inet_conn_established =	selinux_inet_conn_established,
5704 5705 5706
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5707
	.req_classify_flow =		selinux_req_classify_flow,
5708 5709
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5710
	.tun_dev_create =		selinux_tun_dev_create,
5711
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5712
	.tun_dev_attach =		selinux_tun_dev_attach,
5713
	.tun_dev_open =			selinux_tun_dev_open,
5714
	.skb_owned_by =			selinux_skb_owned_by,
5715 5716 5717 5718 5719

#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
5720
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5721 5722
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5723
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5724
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5725
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5726 5727
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5728
#endif
5729 5730

#ifdef CONFIG_KEYS
5731 5732 5733
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5734
	.key_getsecurity =		selinux_key_getsecurity,
5735
#endif
5736 5737 5738 5739 5740 5741 5742

#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
5743 5744 5745 5746
};

static __init int selinux_init(void)
{
5747 5748 5749 5750 5751
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5752 5753 5754 5755 5756 5757 5758 5759
	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
5760
	cred_init_security();
L
Linus Torvalds 已提交
5761

5762 5763
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5764 5765
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5766
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5767 5768
	avc_init();

5769
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5770 5771
		panic("SELinux: Unable to register with kernel.\n");

5772
	if (selinux_enforcing)
5773
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5774
	else
5775
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5776

L
Linus Torvalds 已提交
5777 5778 5779
	return 0;
}

5780 5781 5782 5783 5784
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5785 5786
void selinux_complete_init(void)
{
5787
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5788 5789

	/* Set up any superblocks initialized prior to the policy load. */
5790
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5791
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5792 5793 5794 5795 5796 5797
}

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

5798
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5799

5800 5801 5802 5803
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5804
		.pf =		NFPROTO_IPV4,
5805 5806 5807 5808 5809 5810
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5811
		.pf =		NFPROTO_IPV4,
5812 5813
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5814 5815 5816 5817
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
5818
		.pf =		NFPROTO_IPV4,
5819 5820
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5821
	}
L
Linus Torvalds 已提交
5822 5823 5824 5825
};

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

5826 5827 5828 5829
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
5830
		.pf =		NFPROTO_IPV6,
5831 5832 5833 5834 5835 5836
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
5837
		.pf =		NFPROTO_IPV6,
5838 5839 5840
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5841 5842 5843 5844 5845 5846 5847 5848 5849 5850
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5851 5852 5853

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

5854 5855 5856
	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
5857 5858

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5859 5860 5861
	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
5862
#endif	/* IPV6 */
5863

L
Linus Torvalds 已提交
5864 5865 5866 5867 5868 5869 5870 5871 5872
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5873
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5874

5875
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5876
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5877
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5878 5879 5880 5881
#endif	/* IPV6 */
}
#endif

5882
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5883 5884 5885 5886 5887

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5888
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5889 5890

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5891 5892
static int selinux_disabled;

L
Linus Torvalds 已提交
5893 5894 5895 5896 5897 5898 5899 5900 5901 5902 5903 5904 5905 5906 5907
int selinux_disable(void)
{
	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

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

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

	selinux_disabled = 1;
5908
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5909

5910
	reset_security_ops();
L
Linus Torvalds 已提交
5911

5912 5913 5914
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5915 5916 5917 5918 5919 5920 5921 5922 5923
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif