hooks.c 144.9 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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#define NUM_SEL_MNT_OPTS 5
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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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};

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

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

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

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

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

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

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

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

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

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

out_free:
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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)
556
{
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	const struct cred *cred = current_cred();
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	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
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	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
563 564
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
565 566 567
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
568 569 570 571 572 573 574 575 576 577 578

	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
579 580
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
581
		goto out;
582
	}
L
Linus Torvalds 已提交
583

584 585 586 587 588 589 590 591 592 593 594
	/*
	 * 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)
	 */
595
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
596
	    && (num_opts == 0))
597
		goto out;
598

599 600 601 602 603 604 605
	/*
	 * 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;
606 607 608

		if (flags[i] == SE_SBLABELSUPP)
			continue;
609 610
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
611 612 613
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658
			       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
659
		}
660 661
	}

662
	if (sbsec->flags & SE_SBINITIALIZED) {
663
		/* previously mounted with options, but not on this attempt? */
664
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
665 666 667 668 669
			goto out_double_mount;
		rc = 0;
		goto out;
	}

670
	if (strcmp(sb->s_type->name, "proc") == 0)
671
		sbsec->flags |= SE_SBPROC;
672 673

	/* Determine the labeling behavior to use for this filesystem type. */
674
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
675 676
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
677
		       __func__, sb->s_type->name, rc);
678 679
		goto out;
	}
L
Linus Torvalds 已提交
680

681 682
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
683
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
684
		if (rc)
685
			goto out;
L
Linus Torvalds 已提交
686

687
		sbsec->sid = fscontext_sid;
688 689 690 691 692 693 694
	}

	/*
	 * 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.
	 */
695 696
	if (context_sid) {
		if (!fscontext_sid) {
697 698
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
699
			if (rc)
700 701
				goto out;
			sbsec->sid = context_sid;
702
		} else {
703 704
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
705
			if (rc)
706
				goto out;
707
		}
708 709
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
710

711
		sbsec->mntpoint_sid = context_sid;
712
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
713 714
	}

715
	if (rootcontext_sid) {
716 717
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
718
		if (rc)
719
			goto out;
720

721 722
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
723 724
	}

725 726 727 728 729 730
	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
731 732
		}

733 734
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
735
							     sbsec, cred);
736 737 738
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
739

740
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
741 742
	}

743
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
744
out:
745
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
746
	return rc;
747 748 749 750 751
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
752 753
}

754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784
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,
785
					struct super_block *newsb)
L
Linus Torvalds 已提交
786
{
787 788
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
789

790 791 792
	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
793

794 795
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
796
	 * mount options.  thus we can safely deal with this superblock later
797
	 */
798
	if (!ss_initialized)
799
		return 0;
800 801

	/* how can we clone if the old one wasn't set up?? */
802
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
803

804
	/* if fs is reusing a sb, make sure that the contexts match */
805
	if (newsbsec->flags & SE_SBINITIALIZED)
806
		return selinux_cmp_sb_context(oldsb, newsb);
807

808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826
	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
827
	}
828 829 830 831 832
	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
833

834
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
835 836
	}

837 838
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
839
	return 0;
840 841
}

842 843
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
844
{
845
	char *p;
846 847
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
848
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
849

850
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
851

852 853 854 855
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
856

857 858
		if (!*p)
			continue;
L
Linus Torvalds 已提交
859

860
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
861

862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913
		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;
914 915
		case Opt_labelsupport:
			break;
916 917 918 919
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
920 921 922

		}
	}
923

924 925 926 927 928 929 930 931 932 933 934
	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;
	}

935
	if (fscontext) {
936 937
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
938 939
	}
	if (context) {
940 941
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
942 943
	}
	if (rootcontext) {
944 945
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
946 947
	}
	if (defcontext) {
948 949
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
950 951
	}

952 953 954
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

955 956 957 958 959
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
960 961
	return rc;
}
962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988
/*
 * 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
989

A
Adrian Bunk 已提交
990 991
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
992 993 994 995 996
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
997 998 999 1000 1001 1002
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016

		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;
1017 1018 1019 1020
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1021 1022
		default:
			BUG();
1023
			return;
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041
		};
		/* 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);
1042 1043 1044 1045
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1046
		return rc;
1047
	}
1048 1049 1050 1051 1052 1053 1054 1055

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078
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;
}

1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
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
1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104
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:
1105 1106 1107 1108
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1109
		case SOCK_DGRAM:
1110 1111 1112 1113
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1114 1115
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1116
		default:
L
Linus Torvalds 已提交
1117 1118 1119 1120 1121 1122 1123 1124 1125
			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;
1126
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139
			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;
1140 1141
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1142 1143 1144 1145 1146 1147 1148
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1149 1150
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1151 1152 1153 1154 1155 1156
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1157
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1158 1159 1160
				u16 tclass,
				u32 *sid)
{
1161 1162
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1163

1164
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
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1165 1166 1167
	if (!buffer)
		return -ENOMEM;

1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179
	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
Linus Torvalds 已提交
1180 1181 1182 1183 1184
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1185
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
				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;

1208
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1209
	if (isec->initialized)
1210
		goto out_unlock;
L
Linus Torvalds 已提交
1211 1212

	sbsec = inode->i_sb->s_security;
1213
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1214 1215 1216 1217 1218 1219 1220
		/* 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);
1221
		goto out_unlock;
L
Linus Torvalds 已提交
1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240
	}

	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) {
1241 1242 1243 1244 1245 1246 1247 1248 1249
			/*
			 * 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.
			 */
1250
			goto out_unlock;
L
Linus Torvalds 已提交
1251 1252 1253
		}

		len = INITCONTEXTLEN;
1254
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1255 1256 1257
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1258
			goto out_unlock;
L
Linus Torvalds 已提交
1259
		}
1260
		context[len] = '\0';
L
Linus Torvalds 已提交
1261 1262 1263
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1264 1265
			kfree(context);

L
Linus Torvalds 已提交
1266 1267 1268 1269 1270
			/* 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);
1271
				goto out_unlock;
L
Linus Torvalds 已提交
1272 1273
			}
			len = rc;
1274
			context = kmalloc(len+1, GFP_NOFS);
L
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1275 1276 1277
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1278
				goto out_unlock;
L
Linus Torvalds 已提交
1279
			}
1280
			context[len] = '\0';
L
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1281 1282 1283 1284 1285 1286 1287
			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
1288
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1289
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1290 1291
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1292
				goto out_unlock;
L
Linus Torvalds 已提交
1293 1294 1295 1296 1297
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1298
			rc = security_context_to_sid_default(context, rc, &sid,
1299 1300
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1301
			if (rc) {
1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314
				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
1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332
				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);
1333 1334
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1335
		if (rc)
1336
			goto out_unlock;
L
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1337 1338
		isec->sid = sid;
		break;
1339 1340 1341
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1342
	default:
1343
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1344 1345
		isec->sid = sbsec->sid;

1346
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1347
			if (opt_dentry) {
L
Linus Torvalds 已提交
1348
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1349
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1350 1351 1352
							  isec->sclass,
							  &sid);
				if (rc)
1353
					goto out_unlock;
L
Linus Torvalds 已提交
1354 1355 1356 1357 1358 1359 1360 1361
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1362 1363
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1364 1365 1366 1367 1368 1369 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
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
1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409
/*
 * 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);
}

1410
/*
1411
 * Check permission between a pair of tasks, e.g. signal checks,
1412 1413
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1414
 * - this uses the default subjective creds of tsk1
1415 1416 1417
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1418 1419
			 u32 perms)
{
1420 1421
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1422

1423 1424 1425 1426 1427
	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
1428 1429
}

1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445
/*
 * 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);
}

1446 1447 1448 1449
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1450
/* Check whether a task is allowed to use a capability. */
1451
static int cred_has_capability(const struct cred *cred,
1452
			       int cap, int audit)
L
Linus Torvalds 已提交
1453
{
1454
	struct common_audit_data ad;
1455
	struct av_decision avd;
1456
	u16 sclass;
1457
	u32 sid = cred_sid(cred);
1458
	u32 av = CAP_TO_MASK(cap);
1459
	int rc;
L
Linus Torvalds 已提交
1460

1461
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1462 1463
	ad.u.cap = cap;

1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474
	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();
1475
		return -EINVAL;
1476
	}
1477

1478
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1479 1480 1481 1482 1483
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1484
	return rc;
L
Linus Torvalds 已提交
1485 1486 1487 1488 1489 1490
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1491
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1492

1493
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1494 1495 1496 1497 1498 1499
			    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). */
1500
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1501 1502
			  struct inode *inode,
			  u32 perms,
1503 1504
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1505 1506
{
	struct inode_security_struct *isec;
1507
	u32 sid;
L
Linus Torvalds 已提交
1508

1509 1510
	validate_creds(cred);

1511
	if (unlikely(IS_PRIVATE(inode)))
1512 1513
		return 0;

1514
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1515 1516
	isec = inode->i_security;

1517
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1518 1519 1520 1521 1522
}

/* 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. */
1523
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1524 1525 1526 1527
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1528
	struct common_audit_data ad;
1529

1530
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544
	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;

1545
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1546
	ad.u.path = *path;
1547
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1548 1549 1550 1551 1552 1553 1554 1555 1556 1557
}

/* 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. */
1558 1559 1560
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1561 1562
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1563
	struct inode *inode = file_inode(file);
1564
	struct common_audit_data ad;
1565
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1566 1567
	int rc;

1568
	ad.type = LSM_AUDIT_DATA_PATH;
1569
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1570

1571 1572
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1573 1574 1575 1576
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1577
			goto out;
L
Linus Torvalds 已提交
1578 1579 1580
	}

	/* av is zero if only checking access to the descriptor. */
1581
	rc = 0;
L
Linus Torvalds 已提交
1582
	if (av)
1583
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1584

1585 1586
out:
	return rc;
L
Linus Torvalds 已提交
1587 1588 1589 1590 1591 1592 1593
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1594
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1595 1596
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1597
	u32 sid, newsid;
1598
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1599 1600 1601 1602 1603
	int rc;

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

1604 1605 1606
	sid = tsec->sid;
	newsid = tsec->create_sid;

1607
	ad.type = LSM_AUDIT_DATA_DENTRY;
1608
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1609

1610
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1611 1612 1613 1614 1615
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1616
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1617 1618
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1619 1620 1621 1622
		if (rc)
			return rc;
	}

1623
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1624 1625 1626 1627 1628 1629 1630 1631
	if (rc)
		return rc;

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

1632 1633 1634 1635
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1636
	u32 sid = task_sid(ctx);
1637

1638
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1639 1640
}

1641 1642 1643
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1644 1645 1646 1647 1648 1649 1650 1651

/* 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;
1652
	struct common_audit_data ad;
1653
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1654 1655 1656 1657 1658 1659
	u32 av;
	int rc;

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

1660
	ad.type = LSM_AUDIT_DATA_DENTRY;
1661
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1662 1663 1664

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1665
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
	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
1680 1681
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1682 1683 1684
		return 0;
	}

1685
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1686 1687 1688 1689 1690 1691 1692 1693 1694
	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;
1695
	struct common_audit_data ad;
1696
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1697 1698 1699 1700 1701 1702 1703 1704 1705
	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;

1706
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1707

1708
	ad.u.dentry = old_dentry;
1709
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1710 1711 1712
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1713
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1714 1715 1716 1717
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1718
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1719 1720 1721 1722 1723
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1724
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1725 1726 1727
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1728
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1729 1730 1731 1732 1733
	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);
1734
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1735 1736 1737 1738 1739 1740 1741 1742 1743 1744
				  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. */
1745
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1746 1747
			       struct super_block *sb,
			       u32 perms,
1748
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1749 1750
{
	struct superblock_security_struct *sbsec;
1751
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1752 1753

	sbsec = sb->s_security;
1754
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1755 1756 1757 1758 1759 1760 1761
}

/* 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
1762
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784
		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;
}

1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807
/* 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
1808
/*
1809
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1810 1811
 * open permission.
 */
1812
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1813
{
1814
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1815

1816 1817 1818
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1819 1820 1821
	return av;
}

L
Linus Torvalds 已提交
1822 1823
/* Hook functions begin here. */

1824
static int selinux_ptrace_access_check(struct task_struct *child,
1825
				     unsigned int mode)
L
Linus Torvalds 已提交
1826 1827 1828
{
	int rc;

1829
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1830 1831 1832
	if (rc)
		return rc;

1833
	if (mode & PTRACE_MODE_READ) {
1834 1835 1836
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1837 1838
	}

1839
	return current_has_perm(child, PROCESS__PTRACE);
1840 1841 1842 1843 1844 1845
}

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

1846
	rc = cap_ptrace_traceme(parent);
1847 1848 1849 1850
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1851 1852 1853
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1854
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1855 1856 1857
{
	int error;

1858
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1859 1860 1861
	if (error)
		return error;

1862
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1863 1864
}

D
David Howells 已提交
1865 1866 1867 1868
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
1869 1870 1871
{
	int error;

1872
	error = cap_capset(new, old,
D
David Howells 已提交
1873
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1874 1875 1876
	if (error)
		return error;

D
David Howells 已提交
1877
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1878 1879
}

1880 1881 1882 1883 1884 1885 1886 1887 1888 1889
/*
 * (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.
 */

1890 1891
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1892 1893 1894
{
	int rc;

1895
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1896 1897 1898
	if (rc)
		return rc;

1899
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1900 1901 1902 1903
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1904
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1905 1906 1907 1908 1909 1910
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1911 1912 1913 1914 1915
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1916
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1917 1918 1919 1920
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1921
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1922 1923 1924 1925
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1926 1927 1928 1929 1930 1931
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1932 1933
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1934
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1935 1936
}

1937
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1938 1939 1940 1941
{
	int rc;

	switch (type) {
1942 1943
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1944 1945
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1946 1947 1948 1949
	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:
1950 1951
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1952 1953 1954 1955 1956
	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 */
1957 1958 1959
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971
	}
	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.
 */
1972
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1973 1974 1975
{
	int rc, cap_sys_admin = 0;

1976
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1977
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1978 1979 1980
	if (rc == 0)
		cap_sys_admin = 1;

1981
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1982 1983 1984 1985
}

/* binprm security operations */

1986
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1987
{
1988 1989
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1990
	struct inode_security_struct *isec;
1991
	struct common_audit_data ad;
A
Al Viro 已提交
1992
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
1993 1994
	int rc;

1995
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1996 1997 1998
	if (rc)
		return rc;

1999 2000 2001
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2002 2003
		return 0;

2004 2005
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2006 2007 2008
	isec = inode->i_security;

	/* Default to the current task SID. */
2009 2010
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2011

2012
	/* Reset fs, key, and sock SIDs on execve. */
2013 2014 2015
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2016

2017 2018
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2019
		/* Reset exec SID on execve. */
2020
		new_tsec->exec_sid = 0;
2021 2022 2023 2024 2025 2026 2027

		/*
		 * 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
2028 2029
	} else {
		/* Check for a default transition on this program. */
2030
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2031 2032
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2033 2034 2035 2036
		if (rc)
			return rc;
	}

2037
	ad.type = LSM_AUDIT_DATA_PATH;
2038
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2039

2040 2041
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2042
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2043

2044 2045
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2046 2047 2048 2049 2050
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2051
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2052 2053 2054 2055
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2056
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2057 2058 2059 2060
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078
		/* 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();
2079
			tracer = ptrace_parent(current);
2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093
			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
2094

2095 2096
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2097 2098 2099 2100 2101
	}

	return 0;
}

2102
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2103
{
2104
	const struct task_security_struct *tsec = current_security();
2105
	u32 sid, osid;
L
Linus Torvalds 已提交
2106 2107
	int atsecure = 0;

2108 2109 2110 2111
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2112 2113 2114
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2115
		atsecure = avc_has_perm(osid, sid,
2116 2117
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2118 2119
	}

2120
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2121 2122
}

A
Al Viro 已提交
2123 2124 2125 2126 2127
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
2128
/* Derived from fs/exec.c:flush_old_files. */
2129 2130
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2131 2132
{
	struct file *file, *devnull = NULL;
2133
	struct tty_struct *tty;
2134
	int drop_tty = 0;
A
Al Viro 已提交
2135
	unsigned n;
L
Linus Torvalds 已提交
2136

2137
	tty = get_current_tty();
L
Linus Torvalds 已提交
2138
	if (tty) {
N
Nick Piggin 已提交
2139
		spin_lock(&tty_files_lock);
2140
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2141
			struct tty_file_private *file_priv;
2142

L
Linus Torvalds 已提交
2143
			/* Revalidate access to controlling tty.
2144
			   Use path_has_perm on the tty path directly rather
L
Linus Torvalds 已提交
2145 2146 2147
			   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
2148 2149 2150
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2151
			if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2152
				drop_tty = 1;
L
Linus Torvalds 已提交
2153
		}
N
Nick Piggin 已提交
2154
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2155
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2156
	}
2157 2158 2159
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2160 2161

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2162 2163 2164
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2165

A
Al Viro 已提交
2166
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2167 2168 2169 2170 2171 2172 2173
	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
2174
		fput(devnull);
L
Linus Torvalds 已提交
2175 2176
}

2177 2178 2179 2180
/*
 * 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
2181
{
2182 2183 2184
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2185

2186 2187 2188
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2189

2190 2191
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2192

2193 2194
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2195

2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208
	/* 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) {
2209 2210
		/* protect against do_prlimit() */
		task_lock(current);
2211 2212 2213 2214
		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
2215
		}
2216 2217
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2218 2219 2220 2221
	}
}

/*
2222 2223
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2224
 */
2225
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2226
{
2227
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2228
	struct itimerval itimer;
2229
	u32 osid, sid;
L
Linus Torvalds 已提交
2230 2231
	int rc, i;

2232 2233 2234 2235
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2236 2237
		return;

2238 2239 2240 2241 2242 2243 2244 2245
	/* 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
2246 2247 2248 2249 2250
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2251 2252 2253 2254 2255
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2256 2257 2258
		spin_unlock_irq(&current->sighand->siglock);
	}

2259 2260
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2261
	read_lock(&tasklist_lock);
2262
	__wake_up_parent(current, current->real_parent);
2263
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287
}

/* 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)
{
2288 2289 2290
	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) ||
2291 2292
		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
2293 2294 2295 2296 2297 2298 2299
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2300
	} else
L
Linus Torvalds 已提交
2301 2302 2303 2304 2305
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2306 2307
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2308 2309 2310 2311 2312 2313
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2314
	} else
2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326
		*first = 0;

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

2327
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2328 2329 2330 2331
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2332
	int open_quote = 0;
L
Linus Torvalds 已提交
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347

	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 {
2348 2349 2350 2351
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2352 2353 2354
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2355
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2356 2357 2358 2359 2360 2361 2362
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2363
	strcpy(in_save, nosec_save);
2364
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2365 2366 2367 2368
out:
	return rc;
}

2369 2370 2371 2372 2373 2374 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 2410 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
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;

		if (flags[i] == SE_SBLABELSUPP)
			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;
}

2454
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2455
{
2456
	const struct cred *cred = current_cred();
2457
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2458 2459 2460 2461 2462 2463
	int rc;

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

2464 2465 2466 2467
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2468
	ad.type = LSM_AUDIT_DATA_DENTRY;
2469
	ad.u.dentry = sb->s_root;
2470
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2471 2472
}

2473
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2474
{
2475
	const struct cred *cred = current_cred();
2476
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2477

2478
	ad.type = LSM_AUDIT_DATA_DENTRY;
2479
	ad.u.dentry = dentry->d_sb->s_root;
2480
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2481 2482
}

A
Al Viro 已提交
2483
static int selinux_mount(const char *dev_name,
2484
			 struct path *path,
A
Al Viro 已提交
2485
			 const char *type,
2486 2487
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2488
{
2489
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2490 2491

	if (flags & MS_REMOUNT)
2492
		return superblock_has_perm(cred, path->dentry->d_sb,
2493
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2494
	else
E
Eric Paris 已提交
2495
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2496 2497 2498 2499
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2500
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2501

2502
	return superblock_has_perm(cred, mnt->mnt_sb,
2503
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517
}

/* 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);
}

2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
					struct qstr *name, void **ctx,
					u32 *ctxlen)
{
	const struct cred *cred = current_cred();
	struct task_security_struct *tsec;
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
	struct inode *dir = dentry->d_parent->d_inode;
	u32 newsid;
	int rc;

	tsec = cred->security;
	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
		newsid = tsec->create_sid;
	} else {
		rc = security_transition_sid(tsec->sid, dsec->sid,
					     inode_mode_to_security_class(mode),
					     name,
					     &newsid);
		if (rc) {
			printk(KERN_WARNING
				"%s: security_transition_sid failed, rc=%d\n",
			       __func__, -rc);
			return rc;
		}
	}

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

2552
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2553 2554
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2555
{
2556
	const struct task_security_struct *tsec = current_security();
2557 2558
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2559
	u32 sid, newsid, clen;
2560
	int rc;
2561
	char *namep = NULL, *context;
2562 2563 2564 2565

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

2566 2567 2568
	sid = tsec->sid;
	newsid = tsec->create_sid;

2569 2570 2571 2572
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2573
		rc = security_transition_sid(sid, dsec->sid,
2574
					     inode_mode_to_security_class(inode->i_mode),
2575
					     qstr, &newsid);
2576 2577 2578 2579
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2580
			       __func__,
2581 2582 2583 2584 2585
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2586
	/* Possibly defer initialization to selinux_complete_init. */
2587
	if (sbsec->flags & SE_SBINITIALIZED) {
2588 2589 2590 2591 2592
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2593

2594
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2595 2596
		return -EOPNOTSUPP;

2597
	if (name) {
2598
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2599 2600 2601 2602
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2603

2604
	if (value && len) {
2605
		rc = security_sid_to_context_force(newsid, &context, &clen);
2606 2607 2608 2609 2610 2611
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2612 2613 2614 2615 2616
	}

	return 0;
}

A
Al Viro 已提交
2617
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636
{
	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);
}

2637
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2638 2639 2640 2641 2642 2643 2644 2645 2646
{
	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
2647
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2648 2649 2650 2651 2652
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2653
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2654 2655 2656 2657 2658 2659
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2660 2661
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2662
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2663 2664 2665 2666
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2667
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2668

E
Eric Paris 已提交
2669
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2670 2671
}

2672 2673 2674
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2675
{
2676
	struct common_audit_data ad;
2677 2678 2679
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2680
	ad.type = LSM_AUDIT_DATA_INODE;
2681 2682 2683 2684 2685 2686 2687 2688 2689
	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;
}

2690
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2691
{
2692
	const struct cred *cred = current_cred();
2693 2694
	u32 perms;
	bool from_access;
2695
	unsigned flags = mask & MAY_NOT_BLOCK;
2696 2697 2698 2699 2700
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2701

2702
	from_access = mask & MAY_ACCESS;
2703 2704
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2705 2706
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2707 2708
		return 0;

2709
	validate_creds(cred);
2710

2711 2712
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2713 2714 2715

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

2716 2717 2718 2719 2720 2721 2722 2723 2724 2725
	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;

2726
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2727 2728 2729
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2730 2731 2732 2733
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2734
	const struct cred *cred = current_cred();
2735
	unsigned int ia_valid = iattr->ia_valid;
2736
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2737

2738 2739 2740 2741 2742 2743 2744
	/* 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
2745

2746 2747
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2748
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2749

2750
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2751 2752 2753
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2754 2755 2756 2757
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2758
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2759 2760 2761 2762
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2763

E
Eric Paris 已提交
2764
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2765 2766
}

2767
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2768
{
2769 2770
	const struct cred *cred = current_cred();

2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784
	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
2785
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2786 2787
}

2788 2789
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
2790 2791 2792 2793
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2794
	struct common_audit_data ad;
2795
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2796 2797
	int rc = 0;

2798 2799
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2800 2801

	sbsec = inode->i_sb->s_security;
2802
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2803 2804
		return -EOPNOTSUPP;

2805
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2806 2807
		return -EPERM;

2808
	ad.type = LSM_AUDIT_DATA_DENTRY;
2809
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2810

2811
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2812 2813 2814 2815 2816
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2817
	if (rc == -EINVAL) {
2818 2819 2820 2821 2822 2823 2824
		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 */
2825 2826 2827 2828 2829 2830 2831 2832 2833 2834
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2835 2836 2837 2838 2839
			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);

2840
			return rc;
2841
		}
2842 2843
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2844 2845 2846
	if (rc)
		return rc;

2847
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2848 2849 2850 2851
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2852
	rc = security_validate_transition(isec->sid, newsid, sid,
2853
					  isec->sclass);
L
Linus Torvalds 已提交
2854 2855 2856 2857 2858 2859 2860 2861 2862 2863
	if (rc)
		return rc;

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

2864
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2865
					const void *value, size_t size,
2866
					int flags)
L
Linus Torvalds 已提交
2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877
{
	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;
	}

2878
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2879
	if (rc) {
2880 2881 2882
		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
2883 2884 2885 2886 2887 2888 2889
		return;
	}

	isec->sid = newsid;
	return;
}

2890
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2891
{
2892 2893
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2894
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2895 2896
}

2897
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2898
{
2899 2900
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2901
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2902 2903
}

2904
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2905
{
2906 2907
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2908 2909 2910 2911 2912 2913

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

2914
/*
2915
 * Copy the inode security context value to the user.
2916 2917 2918
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2919
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2920
{
2921 2922 2923
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2924
	struct inode_security_struct *isec = inode->i_security;
2925

2926 2927
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2928

2929 2930 2931 2932 2933 2934 2935 2936 2937
	/*
	 * 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.
	 */
2938
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2939
				SECURITY_CAP_NOAUDIT);
2940 2941 2942 2943 2944
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2945 2946 2947 2948 2949 2950 2951 2952 2953 2954
	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
2955 2956 2957
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2958
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969
{
	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;

2970
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2971 2972 2973 2974
	if (rc)
		return rc;

	isec->sid = newsid;
2975
	isec->initialized = 1;
L
Linus Torvalds 已提交
2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986
	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;
}

2987 2988 2989 2990 2991 2992
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
2993 2994
/* file security operations */

2995
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2996
{
2997
	const struct cred *cred = current_cred();
A
Al Viro 已提交
2998
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
2999 3000 3001 3002 3003

	/* 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;

3004 3005
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3006 3007
}

3008 3009
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3010
	struct inode *inode = file_inode(file);
3011 3012 3013 3014
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3015
	if (!mask)
3016 3017 3018
		/* No permission to check.  Existence test. */
		return 0;

3019 3020
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3021
		/* No change since file_open check. */
3022 3023
		return 0;

3024 3025 3026
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039
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)
{
3040
	const struct cred *cred = current_cred();
3041
	int error = 0;
L
Linus Torvalds 已提交
3042

3043 3044 3045 3046 3047 3048 3049
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3050
	case FS_IOC_GETFLAGS:
3051
	/* fall through */
3052
	case FS_IOC_GETVERSION:
3053 3054
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3055

3056
	case FS_IOC_SETFLAGS:
3057
	/* fall through */
3058
	case FS_IOC_SETVERSION:
3059 3060 3061 3062 3063 3064 3065 3066 3067
		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
3068

3069 3070
	case KDSKBENT:
	case KDSKBSENT:
3071 3072
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3073 3074 3075 3076 3077 3078 3079 3080 3081
		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
3082 3083
}

3084 3085
static int default_noexec;

L
Linus Torvalds 已提交
3086 3087
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3088
	const struct cred *cred = current_cred();
D
David Howells 已提交
3089
	int rc = 0;
3090

3091 3092
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3093 3094 3095 3096 3097
		/*
		 * 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
3098
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3099
		if (rc)
D
David Howells 已提交
3100
			goto error;
L
Linus Torvalds 已提交
3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113
	}

	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;

3114
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3115
	}
D
David Howells 已提交
3116 3117 3118

error:
	return rc;
L
Linus Torvalds 已提交
3119 3120
}

3121
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3122
{
3123
	int rc = 0;
3124
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3125

3126 3127 3128 3129 3130 3131
	/*
	 * 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.
	 */
3132
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3133 3134
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3135 3136 3137 3138 3139
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3140 3141
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3142

3143 3144 3145
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156
	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)
{
3157
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3158 3159 3160 3161

	if (selinux_checkreqprot)
		prot = reqprot;

3162 3163
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3164
		int rc = 0;
3165 3166
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3167
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3168 3169 3170
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3171
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3172 3173 3174 3175 3176 3177 3178 3179
		} 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
3180
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3181
		}
3182 3183 3184
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3185 3186 3187 3188 3189 3190

	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)
{
3191 3192 3193
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3194 3195 3196 3197 3198
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3199
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3200 3201 3202
	int err = 0;

	switch (cmd) {
3203 3204
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3205
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3206
			break;
3207 3208 3209 3210 3211 3212 3213
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3214
	case F_GETOWNER_UIDS:
3215
		/* Just check FD__USE permission */
3216
		err = file_has_perm(cred, file, 0);
3217 3218 3219 3220
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3221
#if BITS_PER_LONG == 32
3222 3223 3224
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3225
#endif
3226
		err = file_has_perm(cred, file, FILE__LOCK);
3227
		break;
L
Linus Torvalds 已提交
3228 3229 3230 3231 3232 3233 3234 3235 3236 3237
	}

	return err;
}

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

	fsec = file->f_security;
3238
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3239 3240 3241 3242 3243 3244 3245

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3246
	struct file *file;
3247
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3248 3249 3250 3251
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3252
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3253 3254 3255 3256 3257 3258 3259 3260

	fsec = file->f_security;

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

3261
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3262 3263 3264 3265 3266
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3267 3268 3269
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3270 3271
}

3272
static int selinux_file_open(struct file *file, const struct cred *cred)
3273 3274 3275
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3276

3277
	fsec = file->f_security;
A
Al Viro 已提交
3278
	isec = file_inode(file)->i_security;
3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295
	/*
	 * 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.
	 */
3296
	return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3297 3298
}

L
Linus Torvalds 已提交
3299 3300 3301 3302
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3303
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3304 3305
}

3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320
/*
 * 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
3321 3322 3323 3324
/*
 * 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
3325
{
D
David Howells 已提交
3326
	struct task_security_struct *tsec = cred->security;
3327

3328 3329 3330 3331 3332
	/*
	 * 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);
3333
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3334 3335
	kfree(tsec);
}
L
Linus Torvalds 已提交
3336

D
David Howells 已提交
3337 3338 3339 3340 3341 3342 3343 3344
/*
 * 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
3345

D
David Howells 已提交
3346
	old_tsec = old->security;
L
Linus Torvalds 已提交
3347

D
David Howells 已提交
3348 3349 3350
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3351

D
David Howells 已提交
3352
	new->security = tsec;
L
Linus Torvalds 已提交
3353 3354 3355
	return 0;
}

3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366
/*
 * 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;
}

3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407
/*
 * 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;
3408
	return ret;
3409 3410
}

3411
static int selinux_kernel_module_request(char *kmod_name)
3412
{
3413 3414 3415 3416 3417
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3418
	ad.type = LSM_AUDIT_DATA_KMOD;
3419 3420 3421 3422
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3423 3424
}

L
Linus Torvalds 已提交
3425 3426
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3427
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3428 3429 3430 3431
}

static int selinux_task_getpgid(struct task_struct *p)
{
3432
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3433 3434 3435 3436
}

static int selinux_task_getsid(struct task_struct *p)
{
3437
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3438 3439
}

3440 3441
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3442
	*secid = task_sid(p);
3443 3444
}

L
Linus Torvalds 已提交
3445 3446 3447 3448
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3449
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3450 3451 3452
	if (rc)
		return rc;

3453
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3454 3455
}

3456 3457
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3458 3459
	int rc;

3460
	rc = cap_task_setioprio(p, ioprio);
3461 3462 3463
	if (rc)
		return rc;

3464
	return current_has_perm(p, PROCESS__SETSCHED);
3465 3466
}

3467 3468
static int selinux_task_getioprio(struct task_struct *p)
{
3469
	return current_has_perm(p, PROCESS__GETSCHED);
3470 3471
}

3472 3473
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3474
{
3475
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3476 3477 3478 3479

	/* 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
3480
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3481
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3482
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3483 3484 3485 3486

	return 0;
}

3487
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3488
{
3489 3490
	int rc;

3491
	rc = cap_task_setscheduler(p);
3492 3493 3494
	if (rc)
		return rc;

3495
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3496 3497 3498 3499
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3500
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3501 3502
}

3503 3504
static int selinux_task_movememory(struct task_struct *p)
{
3505
	return current_has_perm(p, PROCESS__SETSCHED);
3506 3507
}

3508 3509
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3510 3511 3512 3513 3514 3515 3516 3517
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3518
	if (secid)
3519 3520
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3521
	else
3522
		rc = current_has_perm(p, perm);
3523
	return rc;
L
Linus Torvalds 已提交
3524 3525 3526 3527
}

static int selinux_task_wait(struct task_struct *p)
{
3528
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3529 3530 3531 3532 3533 3534
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3535
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3536

3537
	isec->sid = sid;
L
Linus Torvalds 已提交
3538 3539 3540 3541
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3542
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3543
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3544 3545 3546 3547
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3548
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3549 3550 3551 3552 3553 3554 3555 3556
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3557 3558
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3559 3560
	ret = 0;

3561 3562 3563
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3564
	switch (ih->protocol) {
3565 3566
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3567

3568 3569
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3570 3571 3572 3573 3574 3575

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

3576 3577
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3578
		break;
3579 3580 3581 3582 3583 3584 3585 3586
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3587
		offset += ihlen;
3588
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3589
		if (uh == NULL)
3590
			break;
L
Linus Torvalds 已提交
3591

3592 3593
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3594 3595
		break;
	}
L
Linus Torvalds 已提交
3596

J
James Morris 已提交
3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607
	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;

3608 3609
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3610
		break;
3611
	}
J
James Morris 已提交
3612

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

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

/* Returns error only if unable to parse addresses */
3623
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3624
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3625 3626 3627 3628
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3629
	__be16 frag_off;
L
Linus Torvalds 已提交
3630

3631
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3632 3633 3634 3635
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3636 3637
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3638 3639 3640 3641
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3642
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3643 3644 3645
	if (offset < 0)
		goto out;

3646 3647 3648
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3649 3650
	switch (nexthdr) {
	case IPPROTO_TCP: {
3651
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3652 3653 3654 3655 3656

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

3657 3658
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3659 3660 3661 3662 3663 3664 3665 3666 3667 3668
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3669 3670
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3671 3672 3673
		break;
	}

J
James Morris 已提交
3674 3675 3676 3677 3678 3679 3680
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3681 3682
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3683
		break;
3684
	}
J
James Morris 已提交
3685

L
Linus Torvalds 已提交
3686 3687 3688 3689 3690 3691 3692 3693 3694 3695
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3696
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3697
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3698
{
3699 3700
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3701

3702
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3703
	case PF_INET:
3704
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3705 3706
		if (ret)
			goto parse_error;
3707 3708
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3709
		goto okay;
L
Linus Torvalds 已提交
3710 3711 3712

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3713
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3714 3715
		if (ret)
			goto parse_error;
3716 3717
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3718
		goto okay;
L
Linus Torvalds 已提交
3719 3720
#endif	/* IPV6 */
	default:
3721 3722
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3723 3724
	}

3725 3726 3727 3728
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3729
	return ret;
3730 3731 3732 3733 3734

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3735 3736
}

3737
/**
3738
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3739
 * @skb: the packet
3740
 * @family: protocol family
3741
 * @sid: the packet's peer label SID
3742 3743
 *
 * Description:
3744 3745 3746 3747 3748 3749
 * 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.
3750 3751
 *
 */
3752
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3753
{
3754
	int err;
3755 3756
	u32 xfrm_sid;
	u32 nlbl_sid;
3757
	u32 nlbl_type;
3758 3759

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3760
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3761

3762 3763 3764 3765 3766
	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");
3767
		return -EACCES;
3768
	}
3769 3770

	return 0;
3771 3772
}

L
Linus Torvalds 已提交
3773
/* socket security operations */
3774

3775 3776
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3777
{
3778 3779 3780 3781 3782 3783 3784
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3785 3786
}

3787
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3788
{
3789
	struct sk_security_struct *sksec = sk->sk_security;
3790
	struct common_audit_data ad;
3791
	struct lsm_network_audit net = {0,};
3792
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3793

3794 3795
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3796

3797
	ad.type = LSM_AUDIT_DATA_NET;
3798 3799
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3800

3801
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3802 3803 3804 3805 3806
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3807
	const struct task_security_struct *tsec = current_security();
3808
	u32 newsid;
3809
	u16 secclass;
3810
	int rc;
L
Linus Torvalds 已提交
3811 3812

	if (kern)
3813
		return 0;
3814 3815

	secclass = socket_type_to_security_class(family, type, protocol);
3816 3817 3818 3819
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3820
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3821 3822
}

V
Venkat Yekkirala 已提交
3823 3824
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3825
{
3826
	const struct task_security_struct *tsec = current_security();
3827
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3828
	struct sk_security_struct *sksec;
3829 3830
	int err = 0;

3831 3832
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3833 3834
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3835 3836 3837 3838 3839
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3840

L
Linus Torvalds 已提交
3841 3842
	isec->initialized = 1;

3843 3844 3845
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3846
		sksec->sclass = isec->sclass;
3847
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3848 3849
	}

V
Venkat Yekkirala 已提交
3850
	return err;
L
Linus Torvalds 已提交
3851 3852 3853 3854 3855 3856 3857 3858
}

/* 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)
{
3859
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3860 3861 3862
	u16 family;
	int err;

3863
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3864 3865 3866 3867 3868
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3869 3870
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3871
	 */
3872
	family = sk->sk_family;
L
Linus Torvalds 已提交
3873 3874
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3875
		struct sk_security_struct *sksec = sk->sk_security;
3876
		struct common_audit_data ad;
3877
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3878 3879 3880
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3881
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892

		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;
		}

3893 3894 3895 3896 3897 3898
		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
3899 3900
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3901 3902
				if (err)
					goto out;
3903
				ad.type = LSM_AUDIT_DATA_NET;
3904 3905 3906
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
3907 3908
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3909 3910 3911 3912
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3913
		}
3914

3915
		switch (sksec->sclass) {
3916
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3917 3918
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3919

3920
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3921 3922
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3923 3924 3925 3926 3927

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3928 3929 3930 3931
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3932

3933
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3934 3935
		if (err)
			goto out;
3936

3937
		ad.type = LSM_AUDIT_DATA_NET;
3938 3939 3940
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
3941 3942

		if (family == PF_INET)
3943
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
3944
		else
3945
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3946

3947 3948
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3949 3950 3951 3952 3953 3954 3955 3956 3957
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3958
	struct sock *sk = sock->sk;
3959
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3960 3961
	int err;

3962
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3963 3964 3965 3966
	if (err)
		return err;

	/*
J
James Morris 已提交
3967
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3968
	 */
3969 3970
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3971
		struct common_audit_data ad;
3972
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3973 3974 3975
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3976
		u32 sid, perm;
L
Linus Torvalds 已提交
3977 3978 3979

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3980
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3981 3982 3983 3984
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3985
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3986 3987 3988 3989
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3990
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3991 3992 3993
		if (err)
			goto out;

3994
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3995 3996
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3997
		ad.type = LSM_AUDIT_DATA_NET;
3998 3999 4000
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4001
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4002 4003 4004 4005
		if (err)
			goto out;
	}

4006 4007
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4008 4009 4010 4011 4012 4013
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4014
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4015 4016 4017 4018 4019 4020 4021 4022
}

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

4023
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037
	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,
4038
				  int size)
L
Linus Torvalds 已提交
4039
{
4040
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4041 4042 4043 4044 4045
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4046
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4047 4048 4049 4050
}

static int selinux_socket_getsockname(struct socket *sock)
{
4051
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4052 4053 4054 4055
}

static int selinux_socket_getpeername(struct socket *sock)
{
4056
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4057 4058
}

4059
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4060
{
4061 4062
	int err;

4063
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4064 4065 4066 4067
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4068 4069 4070 4071 4072
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4073
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4074 4075 4076 4077
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4078
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4079 4080
}

4081 4082
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4083 4084
					      struct sock *newsk)
{
4085 4086
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4087
	struct sk_security_struct *sksec_new = newsk->sk_security;
4088
	struct common_audit_data ad;
4089
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4090 4091
	int err;

4092
	ad.type = LSM_AUDIT_DATA_NET;
4093 4094
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4095

4096 4097
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4098 4099 4100 4101 4102
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4103 4104 4105 4106 4107
	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;
4108

4109 4110 4111 4112
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4113 4114 4115 4116 4117
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4118 4119
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4120
	struct common_audit_data ad;
4121
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4122

4123
	ad.type = LSM_AUDIT_DATA_NET;
4124 4125
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4126

4127 4128
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4129 4130
}

4131 4132
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4133
				    struct common_audit_data *ad)
4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153
{
	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);
}

4154
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4155
				       u16 family)
4156
{
4157
	int err = 0;
4158 4159
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4160
	struct common_audit_data ad;
4161
	struct lsm_network_audit net = {0,};
4162 4163
	char *addrp;

4164
	ad.type = LSM_AUDIT_DATA_NET;
4165 4166 4167
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4168 4169 4170
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4171

4172
	if (selinux_secmark_enabled()) {
4173
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4174
				   PACKET__RECV, &ad);
4175 4176 4177
		if (err)
			return err;
	}
4178

4179 4180 4181 4182
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4183

4184 4185 4186 4187 4188
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4189
	int err;
4190
	struct sk_security_struct *sksec = sk->sk_security;
4191 4192
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4193
	struct common_audit_data ad;
4194
	struct lsm_network_audit net = {0,};
4195
	char *addrp;
4196 4197
	u8 secmark_active;
	u8 peerlbl_active;
4198 4199

	if (family != PF_INET && family != PF_INET6)
4200
		return 0;
4201 4202

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4203
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4204 4205
		family = PF_INET;

4206 4207 4208 4209
	/* 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. */
4210
	if (!selinux_policycap_netpeer)
4211 4212 4213 4214 4215 4216 4217
		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;

4218
	ad.type = LSM_AUDIT_DATA_NET;
4219 4220 4221
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4222
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4223
	if (err)
4224
		return err;
4225

4226
	if (peerlbl_active) {
4227 4228 4229
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4230 4231
		if (err)
			return err;
4232
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4233
					       peer_sid, &ad);
4234 4235
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4236
			return err;
4237
		}
4238 4239
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4240 4241
		if (err)
			selinux_netlbl_err(skb, err, 0);
4242 4243
	}

4244
	if (secmark_active) {
4245 4246 4247 4248 4249 4250
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4251
	return err;
L
Linus Torvalds 已提交
4252 4253
}

C
Catherine Zhang 已提交
4254 4255
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4256 4257 4258 4259
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4260
	struct sk_security_struct *sksec = sock->sk->sk_security;
4261
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4262

4263 4264
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4265
		peer_sid = sksec->peer_sid;
4266 4267
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4268

C
Catherine Zhang 已提交
4269
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4270
	if (err)
4271
		return err;
L
Linus Torvalds 已提交
4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287

	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;
}

4288
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4289
{
4290
	u32 peer_secid = SECSID_NULL;
4291
	u16 family;
C
Catherine Zhang 已提交
4292

4293 4294 4295 4296 4297
	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)
4298 4299 4300 4301 4302
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4303
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4304
	else if (skb)
4305
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4306

4307
out:
4308
	*secid = peer_secid;
4309 4310 4311
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4312 4313
}

A
Al Viro 已提交
4314
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4315
{
4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327
	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
4328 4329 4330 4331
}

static void selinux_sk_free_security(struct sock *sk)
{
4332 4333 4334 4335 4336
	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
4337 4338
}

4339
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4340
{
4341 4342
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4343

4344 4345 4346
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4347

4348
	selinux_netlbl_sk_security_reset(newsksec);
4349 4350
}

V
Venkat Yekkirala 已提交
4351
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4352
{
4353
	if (!sk)
V
Venkat Yekkirala 已提交
4354
		*secid = SECINITSID_ANY_SOCKET;
4355 4356
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4357

V
Venkat Yekkirala 已提交
4358
		*secid = sksec->sid;
4359
	}
4360 4361
}

4362
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4363 4364 4365 4366
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4367 4368 4369
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4370
	sksec->sclass = isec->sclass;
4371 4372
}

4373 4374
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4375 4376 4377
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4378
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4379
	u32 newsid;
4380 4381
	u32 peersid;

4382 4383 4384 4385 4386
	/* 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);
4387 4388
	if (err)
		return err;
4389 4390
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4391
		req->peer_secid = SECSID_NULL;
4392 4393 4394 4395 4396 4397
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4398 4399
	}

4400
	return selinux_netlbl_inet_conn_request(req, family);
4401 4402
}

4403 4404
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4405 4406 4407 4408
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4409
	newsksec->peer_sid = req->peer_secid;
4410 4411 4412 4413
	/* 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. */
4414

P
Paul Moore 已提交
4415 4416
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4417
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4418 4419
}

4420
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4421
{
4422
	u16 family = sk->sk_family;
4423 4424
	struct sk_security_struct *sksec = sk->sk_security;

4425 4426 4427 4428 4429
	/* 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);
4430 4431
}

4432 4433 4434 4435 4436
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457
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);
}

4458 4459
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4460
{
4461
	fl->flowi_secid = req->secid;
4462 4463
}

4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481
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);
}

4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496
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);
}

4497
static int selinux_tun_dev_attach_queue(void *security)
4498
{
4499 4500 4501 4502 4503 4504 4505 4506 4507
	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;
4508 4509 4510 4511 4512 4513 4514 4515 4516
	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 */

4517
	sksec->sid = tunsec->sid;
4518
	sksec->sclass = SECCLASS_TUN_SOCKET;
4519 4520

	return 0;
4521 4522
}

4523
static int selinux_tun_dev_open(void *security)
4524
{
4525
	struct tun_security_struct *tunsec = security;
4526 4527 4528
	u32 sid = current_sid();
	int err;

4529
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4530 4531 4532 4533 4534 4535 4536
			   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;
4537
	tunsec->sid = sid;
4538 4539 4540 4541

	return 0;
}

L
Linus Torvalds 已提交
4542 4543 4544 4545 4546
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4547
	struct sk_security_struct *sksec = sk->sk_security;
4548

4549
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4550 4551 4552
		err = -EINVAL;
		goto out;
	}
4553
	nlh = nlmsg_hdr(skb);
4554

4555
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4556 4557
	if (err) {
		if (err == -EINVAL) {
4558
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4559 4560
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4561
				  nlh->nlmsg_type, sksec->sclass);
4562
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4563 4564 4565 4566 4567 4568 4569 4570 4571
				err = 0;
		}

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

4572
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4573 4574 4575 4576 4577 4578
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4579 4580
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4581
{
4582
	int err;
4583 4584
	char *addrp;
	u32 peer_sid;
4585
	struct common_audit_data ad;
4586
	struct lsm_network_audit net = {0,};
4587
	u8 secmark_active;
4588
	u8 netlbl_active;
4589
	u8 peerlbl_active;
4590

4591 4592
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4593

4594
	secmark_active = selinux_secmark_enabled();
4595 4596
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4597 4598
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4599

4600 4601 4602
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4603
	ad.type = LSM_AUDIT_DATA_NET;
4604 4605 4606
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4607 4608 4609
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4610 4611 4612 4613 4614
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4615
			return NF_DROP;
4616 4617
		}
	}
4618 4619 4620 4621 4622 4623

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

4624 4625 4626 4627 4628 4629 4630 4631
	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;

4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654
	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 */

4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685
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);
}

4686 4687
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4688
						u16 family)
4689 4690 4691
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4692
	struct common_audit_data ad;
4693
	struct lsm_network_audit net = {0,};
4694 4695
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4696

4697 4698 4699 4700
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4701
	ad.type = LSM_AUDIT_DATA_NET;
4702 4703 4704
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4705 4706 4707
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4708
	if (selinux_secmark_enabled())
4709
		if (avc_has_perm(sksec->sid, skb->secmark,
4710
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4711
			return NF_DROP_ERR(-ECONNREFUSED);
4712

4713 4714
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4715 4716

	return NF_ACCEPT;
4717 4718
}

4719 4720
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4721
{
4722 4723
	u32 secmark_perm;
	u32 peer_sid;
4724
	struct sock *sk;
4725
	struct common_audit_data ad;
4726
	struct lsm_network_audit net = {0,};
4727 4728 4729
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4730

4731 4732 4733 4734
	/* 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. */
4735
	if (!selinux_policycap_netpeer)
4736
		return selinux_ip_postroute_compat(skb, ifindex, family);
4737
#ifdef CONFIG_XFRM
4738 4739 4740 4741 4742 4743
	/* 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
4744
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4745
		return NF_ACCEPT;
4746
#endif
4747 4748 4749 4750 4751
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4752 4753 4754 4755
	/* 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 */
4756
	sk = skb->sk;
4757
	if (sk == NULL) {
4758 4759
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4760
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4761
				return NF_DROP;
4762 4763
		} else {
			secmark_perm = PACKET__SEND;
4764
			peer_sid = SECINITSID_KERNEL;
4765
		}
4766
	} else {
4767 4768 4769 4770
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4771

4772
	ad.type = LSM_AUDIT_DATA_NET;
4773 4774 4775
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4776
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4777
		return NF_DROP;
4778

4779 4780 4781
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4782
			return NF_DROP_ERR(-ECONNREFUSED);
4783 4784 4785 4786 4787 4788

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4789
			return NF_DROP;
4790 4791
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4792
			return NF_DROP_ERR(-ECONNREFUSED);
4793 4794

		if (sel_netnode_sid(addrp, family, &node_sid))
4795
			return NF_DROP;
4796 4797
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4798
			return NF_DROP_ERR(-ECONNREFUSED);
4799
	}
4800

4801
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4802 4803
}

4804 4805 4806 4807 4808
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
4809
{
4810
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4811 4812 4813
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4814 4815 4816 4817 4818
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
4819
{
4820
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4821 4822 4823 4824 4825 4826 4827 4828 4829
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4830
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4831 4832 4833
	if (err)
		return err;

4834
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4835 4836 4837 4838 4839 4840 4841
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4842
	u32 sid;
L
Linus Torvalds 已提交
4843

J
James Morris 已提交
4844
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4845 4846 4847
	if (!isec)
		return -ENOMEM;

4848
	sid = task_sid(task);
L
Linus Torvalds 已提交
4849
	isec->sclass = sclass;
4850
	isec->sid = sid;
L
Linus Torvalds 已提交
4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866
	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
4867
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885
	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,
4886
			u32 perms)
L
Linus Torvalds 已提交
4887 4888
{
	struct ipc_security_struct *isec;
4889
	struct common_audit_data ad;
4890
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4891 4892 4893

	isec = ipc_perms->security;

4894
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4895 4896
	ad.u.ipc_id = ipc_perms->key;

4897
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913
}

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;
4914
	struct common_audit_data ad;
4915
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4916 4917 4918 4919 4920 4921 4922 4923
	int rc;

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

	isec = msq->q_perm.security;

4924
	ad.type = LSM_AUDIT_DATA_IPC;
4925
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4926

4927
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943
			  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;
4944
	struct common_audit_data ad;
4945
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4946 4947 4948

	isec = msq->q_perm.security;

4949
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4950 4951
	ad.u.ipc_id = msq->q_perm.key;

4952
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4953 4954 4955 4956 4957 4958 4959 4960
			    MSGQ__ASSOCIATE, &ad);
}

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

4961
	switch (cmd) {
L
Linus Torvalds 已提交
4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979
	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;
	}

4980
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4981 4982 4983 4984 4985 4986 4987
	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;
4988
	struct common_audit_data ad;
4989
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002
	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
		 */
5003
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5004
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5005 5006 5007 5008
		if (rc)
			return rc;
	}

5009
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5010 5011 5012
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5013
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5014 5015 5016
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5017 5018
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5019 5020
	if (!rc)
		/* Can the message be put in the queue? */
5021 5022
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5023 5024 5025 5026 5027 5028 5029 5030 5031 5032

	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;
5033
	struct common_audit_data ad;
5034
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5035 5036 5037 5038 5039
	int rc;

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

5040
	ad.type = LSM_AUDIT_DATA_IPC;
5041
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5042

5043
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5044 5045
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5046
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5047 5048 5049 5050 5051 5052 5053 5054
				  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;
5055
	struct common_audit_data ad;
5056
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5057 5058 5059 5060 5061 5062 5063 5064
	int rc;

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

	isec = shp->shm_perm.security;

5065
	ad.type = LSM_AUDIT_DATA_IPC;
5066
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5067

5068
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084
			  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;
5085
	struct common_audit_data ad;
5086
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5087 5088 5089

	isec = shp->shm_perm.security;

5090
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5091 5092
	ad.u.ipc_id = shp->shm_perm.key;

5093
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5094 5095 5096 5097 5098 5099 5100 5101 5102
			    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;

5103
	switch (cmd) {
L
Linus Torvalds 已提交
5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125
	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;
	}

5126
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139
	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;

5140
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5141 5142 5143 5144 5145 5146
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5147
	struct common_audit_data ad;
5148
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5149 5150 5151 5152 5153 5154 5155 5156
	int rc;

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

	isec = sma->sem_perm.security;

5157
	ad.type = LSM_AUDIT_DATA_IPC;
5158
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5159

5160
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176
			  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;
5177
	struct common_audit_data ad;
5178
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5179 5180 5181

	isec = sma->sem_perm.security;

5182
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5183 5184
	ad.u.ipc_id = sma->sem_perm.key;

5185
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5186 5187 5188 5189 5190 5191 5192 5193 5194
			    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;

5195
	switch (cmd) {
L
Linus Torvalds 已提交
5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226
	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;
	}

5227
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240
	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;

5241
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256
}

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;

5257
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5258 5259
}

5260 5261 5262 5263 5264 5265
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5266
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5267 5268 5269 5270 5271 5272
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5273
			       char *name, char **value)
L
Linus Torvalds 已提交
5274
{
5275
	const struct task_security_struct *__tsec;
5276
	u32 sid;
L
Linus Torvalds 已提交
5277
	int error;
5278
	unsigned len;
L
Linus Torvalds 已提交
5279 5280

	if (current != p) {
5281
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5282 5283 5284 5285
		if (error)
			return error;
	}

5286 5287
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5288 5289

	if (!strcmp(name, "current"))
5290
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5291
	else if (!strcmp(name, "prev"))
5292
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5293
	else if (!strcmp(name, "exec"))
5294
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5295
	else if (!strcmp(name, "fscreate"))
5296
		sid = __tsec->create_sid;
5297
	else if (!strcmp(name, "keycreate"))
5298
		sid = __tsec->keycreate_sid;
5299
	else if (!strcmp(name, "sockcreate"))
5300
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5301
	else
5302 5303
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5304 5305 5306 5307

	if (!sid)
		return 0;

5308 5309 5310 5311
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5312 5313 5314 5315

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5316 5317 5318 5319 5320 5321
}

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
5322
	struct task_struct *tracer;
D
David Howells 已提交
5323 5324
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339
	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"))
5340
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5341
	else if (!strcmp(name, "fscreate"))
5342
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5343
	else if (!strcmp(name, "keycreate"))
5344
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5345
	else if (!strcmp(name, "sockcreate"))
5346
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5347
	else if (!strcmp(name, "current"))
5348
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360
	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);
5361
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376
			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);

5377
				return error;
5378
			}
5379 5380 5381
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5382 5383 5384 5385
		if (error)
			return error;
	}

D
David Howells 已提交
5386 5387 5388 5389
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5390 5391 5392
	/* 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
5393
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5394 5395
	   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
5396 5397
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5398
		tsec->exec_sid = sid;
D
David Howells 已提交
5399
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5400
		tsec->create_sid = sid;
D
David Howells 已提交
5401
	} else if (!strcmp(name, "keycreate")) {
5402 5403
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5404
			goto abort_change;
5405
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5406
	} else if (!strcmp(name, "sockcreate")) {
5407
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5408 5409
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5410
		if (sid == 0)
D
David Howells 已提交
5411 5412 5413 5414
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5415
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5416 5417 5418
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5419
		}
L
Linus Torvalds 已提交
5420 5421 5422

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5423
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5424
		if (error)
D
David Howells 已提交
5425
			goto abort_change;
L
Linus Torvalds 已提交
5426 5427 5428

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5429
		ptsid = 0;
L
Linus Torvalds 已提交
5430
		task_lock(p);
5431
		tracer = ptrace_parent(p);
D
David Howells 已提交
5432 5433 5434 5435 5436 5437 5438
		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
5439
			if (error)
D
David Howells 已提交
5440
				goto abort_change;
L
Linus Torvalds 已提交
5441 5442
		}

D
David Howells 已提交
5443 5444 5445 5446 5447 5448 5449
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5450
	return size;
D
David Howells 已提交
5451 5452 5453 5454

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5455 5456
}

5457 5458 5459 5460 5461
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5462 5463 5464 5465 5466
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5467
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5468 5469 5470 5471
{
	return security_context_to_sid(secdata, seclen, secid);
}

5472 5473
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5474
	kfree(secdata);
5475 5476
}

5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502
/*
 *	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;
}
5503 5504
#ifdef CONFIG_KEYS

D
David Howells 已提交
5505
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5506
			     unsigned long flags)
5507
{
D
David Howells 已提交
5508
	const struct task_security_struct *tsec;
5509 5510 5511 5512 5513 5514
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5515 5516 5517
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5518
	else
D
David Howells 已提交
5519
		ksec->sid = tsec->sid;
5520

5521
	k->security = ksec;
5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533
	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
5534 5535
				  const struct cred *cred,
				  key_perm_t perm)
5536 5537 5538
{
	struct key *key;
	struct key_security_struct *ksec;
5539
	u32 sid;
5540 5541 5542 5543 5544 5545 5546

	/* 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
5547
	sid = cred_sid(cred);
5548 5549 5550 5551 5552

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5553 5554
}

5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568
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;
}

5569 5570
#endif

L
Linus Torvalds 已提交
5571
static struct security_operations selinux_ops = {
5572 5573
	.name =				"selinux",

5574
	.ptrace_access_check =		selinux_ptrace_access_check,
5575
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5576
	.capget =			selinux_capget,
D
David Howells 已提交
5577
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5578 5579 5580 5581 5582 5583 5584 5585
	.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,

5586 5587 5588
	.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
5589 5590 5591 5592 5593
	.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,
5594
	.sb_remount =			selinux_sb_remount,
5595
	.sb_kern_mount =		selinux_sb_kern_mount,
5596
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5597 5598 5599
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5600
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5601
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5602 5603
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5604
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5605 5606 5607

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5608
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626
	.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,
5627 5628 5629
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5630
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5631 5632 5633 5634 5635

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5636 5637
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5638 5639 5640 5641 5642 5643 5644
	.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,

5645
	.file_open =			selinux_file_open,
5646

L
Linus Torvalds 已提交
5647
	.task_create =			selinux_task_create,
5648
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5649
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5650
	.cred_prepare =			selinux_cred_prepare,
5651
	.cred_transfer =		selinux_cred_transfer,
5652 5653
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5654
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5655 5656
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5657
	.task_getsid =			selinux_task_getsid,
5658
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5659
	.task_setnice =			selinux_task_setnice,
5660
	.task_setioprio =		selinux_task_setioprio,
5661
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5662 5663 5664
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5665
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5666 5667
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5668
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5669 5670

	.ipc_permission =		selinux_ipc_permission,
5671
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688

	.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,

5689 5690
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5691 5692 5693 5694
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5695
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5696

5697 5698
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5699

5700
	.ismaclabel =			selinux_ismaclabel,
5701
	.secid_to_secctx =		selinux_secid_to_secctx,
5702
	.secctx_to_secid =		selinux_secctx_to_secid,
5703
	.release_secctx =		selinux_release_secctx,
5704 5705 5706
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5707

5708
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724
	.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
5725 5726
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5727 5728
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5729
	.sk_clone_security =		selinux_sk_clone_security,
5730
	.sk_getsecid =			selinux_sk_getsecid,
5731 5732 5733
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5734
	.inet_conn_established =	selinux_inet_conn_established,
5735 5736 5737
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5738
	.req_classify_flow =		selinux_req_classify_flow,
5739 5740
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5741
	.tun_dev_create =		selinux_tun_dev_create,
5742
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5743
	.tun_dev_attach =		selinux_tun_dev_attach,
5744
	.tun_dev_open =			selinux_tun_dev_open,
5745
	.skb_owned_by =			selinux_skb_owned_by,
5746 5747 5748 5749 5750

#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
5751
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5752 5753
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5754
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5755
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5756 5757
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5758
#endif
5759 5760

#ifdef CONFIG_KEYS
5761 5762 5763
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5764
	.key_getsecurity =		selinux_key_getsecurity,
5765
#endif
5766 5767 5768 5769 5770 5771 5772

#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
5773 5774 5775 5776
};

static __init int selinux_init(void)
{
5777 5778 5779 5780 5781
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5782 5783 5784 5785 5786 5787 5788 5789
	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
5790
	cred_init_security();
L
Linus Torvalds 已提交
5791

5792 5793
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5794 5795
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5796
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5797 5798
	avc_init();

5799
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5800 5801
		panic("SELinux: Unable to register with kernel.\n");

5802
	if (selinux_enforcing)
5803
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5804
	else
5805
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5806

L
Linus Torvalds 已提交
5807 5808 5809
	return 0;
}

5810 5811 5812 5813 5814
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5815 5816
void selinux_complete_init(void)
{
5817
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5818 5819

	/* Set up any superblocks initialized prior to the policy load. */
5820
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5821
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5822 5823 5824 5825 5826 5827
}

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

5828
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5829

5830 5831 5832 5833
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5834
		.pf =		NFPROTO_IPV4,
5835 5836 5837 5838 5839 5840
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5841
		.pf =		NFPROTO_IPV4,
5842 5843
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5844 5845 5846 5847
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
5848
		.pf =		NFPROTO_IPV4,
5849 5850
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5851
	}
L
Linus Torvalds 已提交
5852 5853 5854 5855
};

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

5856 5857 5858 5859
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
5860
		.pf =		NFPROTO_IPV6,
5861 5862 5863 5864 5865 5866
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
5867
		.pf =		NFPROTO_IPV6,
5868 5869 5870
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5871 5872 5873 5874 5875 5876 5877 5878 5879 5880
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5881 5882 5883

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

5884 5885 5886
	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
5887 5888

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5889 5890 5891
	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
5892
#endif	/* IPV6 */
5893

L
Linus Torvalds 已提交
5894 5895 5896 5897 5898 5899 5900 5901 5902
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5903
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5904

5905
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5906
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5907
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5908 5909 5910 5911
#endif	/* IPV6 */
}
#endif

5912
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5913 5914 5915 5916 5917

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5918
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5919 5920

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5921 5922
static int selinux_disabled;

L
Linus Torvalds 已提交
5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935 5936 5937
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;
5938
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5939

5940
	reset_security_ops();
L
Linus Torvalds 已提交
5941

5942 5943 5944
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5945 5946 5947 5948 5949 5950 5951 5952 5953
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif