hooks.c 144.3 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/sock.h>
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#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
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#include <net/netlink.h>
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#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

enum {
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	Opt_error = -1,
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	Opt_context = 1,
	Opt_fscontext = 2,
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	Opt_defcontext = 3,
	Opt_rootcontext = 4,
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	Opt_labelsupport = 5,
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	Opt_nextmntopt = 6,
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};

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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

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

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

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

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

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

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

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static int sb_finish_set_opts(struct super_block *sb)
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{
	struct superblock_security_struct *sbsec = sb->s_security;
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	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
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	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
		if (!root_inode->i_op->getxattr) {
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
			rc = -EOPNOTSUPP;
			goto out;
		}
		rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
			goto out;
		}
	}
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	sbsec->flags |= (SE_SBINITIALIZED | SBLABEL_MNT);
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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))
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		sbsec->flags &= ~SBLABEL_MNT;
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	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
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		sbsec->flags |= SBLABEL_MNT;
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	/*
	 * Special handling for rootfs. Is genfs but supports
	 * setting SELinux context on in-core inodes.
	 */
	if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
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		sbsec->flags |= SBLABEL_MNT;
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	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
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	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		goto next_inode;
	}
	spin_unlock(&sbsec->isec_lock);
out:
	return rc;
}
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/*
 * This function should allow an FS to ask what it's mount security
 * options were so it can use those later for submounts, displaying
 * mount options, or whatever.
 */
static int selinux_get_mnt_opts(const struct super_block *sb,
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				struct security_mnt_opts *opts)
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{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
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	security_init_mnt_opts(opts);
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	if (!(sbsec->flags & SE_SBINITIALIZED))
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		return -EINVAL;
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	if (!ss_initialized)
		return -EINVAL;
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	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

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

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

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	/* check if the old mount command had the same options */
547
	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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561 562 563 564
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
565 566
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
567
{
568
	const struct cred *cred = current_cred();
569 570 571
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
572 573
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
574 575
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
576 577 578
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
579 580 581 582 583 584 585 586 587 588 589

	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
590 591
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
592
		goto out;
593
	}
L
Linus Torvalds 已提交
594

595 596 597 598 599 600 601 602 603 604 605
	/*
	 * 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)
	 */
606
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
607
	    && (num_opts == 0))
608
		goto out;
609

610 611 612 613 614 615 616
	/*
	 * 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;
617

618
		if (flags[i] == SBLABEL_MNT)
619
			continue;
620 621
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
622 623 624
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669
			       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
670
		}
671 672
	}

673
	if (sbsec->flags & SE_SBINITIALIZED) {
674
		/* previously mounted with options, but not on this attempt? */
675
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
676 677 678 679 680
			goto out_double_mount;
		rc = 0;
		goto out;
	}

681
	if (strcmp(sb->s_type->name, "proc") == 0)
682
		sbsec->flags |= SE_SBPROC;
683 684

	/* Determine the labeling behavior to use for this filesystem type. */
685
	rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
686 687
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
688
		       __func__, sb->s_type->name, rc);
689 690
		goto out;
	}
L
Linus Torvalds 已提交
691

692 693
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
694
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
695
		if (rc)
696
			goto out;
L
Linus Torvalds 已提交
697

698
		sbsec->sid = fscontext_sid;
699 700 701 702 703 704 705
	}

	/*
	 * 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.
	 */
706 707
	if (context_sid) {
		if (!fscontext_sid) {
708 709
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
710
			if (rc)
711 712
				goto out;
			sbsec->sid = context_sid;
713
		} else {
714 715
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
716
			if (rc)
717
				goto out;
718
		}
719 720
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
721

722
		sbsec->mntpoint_sid = context_sid;
723
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
724 725
	}

726
	if (rootcontext_sid) {
727 728
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
729
		if (rc)
730
			goto out;
731

732 733
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
734 735
	}

736 737 738 739 740 741
	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
742 743
		}

744 745
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
746
							     sbsec, cred);
747 748 749
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
750

751
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
752 753
	}

754
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
755
out:
756
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
757
	return rc;
758 759 760 761 762
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
763 764
}

765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795
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,
796
					struct super_block *newsb)
L
Linus Torvalds 已提交
797
{
798 799
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
800

801 802 803
	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
804

805 806
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
807
	 * mount options.  thus we can safely deal with this superblock later
808
	 */
809
	if (!ss_initialized)
810
		return 0;
811 812

	/* how can we clone if the old one wasn't set up?? */
813
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
814

815
	/* if fs is reusing a sb, make sure that the contexts match */
816
	if (newsbsec->flags & SE_SBINITIALIZED)
817
		return selinux_cmp_sb_context(oldsb, newsb);
818

819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837
	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
838
	}
839 840 841 842 843
	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
844

845
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
846 847
	}

848 849
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
850
	return 0;
851 852
}

853 854
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
855
{
856
	char *p;
857 858
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
859
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
860

861
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
862

863 864 865 866
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
867

868 869
		if (!*p)
			continue;
L
Linus Torvalds 已提交
870

871
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
872

873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924
		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;
925 926
		case Opt_labelsupport:
			break;
927 928 929 930
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
931 932 933

		}
	}
934

935 936 937 938 939 940 941 942 943 944 945
	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;
	}

946
	if (fscontext) {
947 948
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
949 950
	}
	if (context) {
951 952
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
953 954
	}
	if (rootcontext) {
955 956
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
957 958
	}
	if (defcontext) {
959 960
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
961 962
	}

963 964 965
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

966 967 968 969 970
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
971 972
	return rc;
}
973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999
/*
 * 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
1000

A
Adrian Bunk 已提交
1001 1002
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1003 1004 1005 1006 1007
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1008 1009 1010 1011 1012 1013
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027

		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;
1028
		case SBLABEL_MNT:
1029 1030 1031
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1032 1033
		default:
			BUG();
1034
			return;
1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052
		};
		/* 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);
1053 1054 1055 1056
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1057
		return rc;
1058
	}
1059 1060 1061 1062 1063 1064 1065 1066

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089
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;
}

1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
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
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115
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:
1116 1117 1118 1119
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1120
		case SOCK_DGRAM:
1121 1122 1123 1124
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1125 1126
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1127
		default:
L
Linus Torvalds 已提交
1128 1129 1130 1131 1132 1133 1134 1135 1136
			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;
1137
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150
			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;
1151 1152
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1153 1154 1155 1156 1157 1158 1159
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1160 1161
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1162 1163 1164 1165 1166 1167
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1168
static int selinux_proc_get_sid(struct dentry *dentry,
L
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1169 1170 1171
				u16 tclass,
				u32 *sid)
{
1172 1173
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1174

1175
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1176 1177 1178
	if (!buffer)
		return -ENOMEM;

1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
	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
1191 1192 1193 1194 1195
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1196
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218
				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;

1219
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1220
	if (isec->initialized)
1221
		goto out_unlock;
L
Linus Torvalds 已提交
1222 1223

	sbsec = inode->i_sb->s_security;
1224
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1225 1226 1227 1228 1229 1230 1231
		/* 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);
1232
		goto out_unlock;
L
Linus Torvalds 已提交
1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251
	}

	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) {
1252 1253 1254 1255 1256 1257 1258 1259 1260
			/*
			 * 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.
			 */
1261
			goto out_unlock;
L
Linus Torvalds 已提交
1262 1263 1264
		}

		len = INITCONTEXTLEN;
1265
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1266 1267 1268
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1269
			goto out_unlock;
L
Linus Torvalds 已提交
1270
		}
1271
		context[len] = '\0';
L
Linus Torvalds 已提交
1272 1273 1274
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1275 1276
			kfree(context);

L
Linus Torvalds 已提交
1277 1278 1279 1280 1281
			/* 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);
1282
				goto out_unlock;
L
Linus Torvalds 已提交
1283 1284
			}
			len = rc;
1285
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1286 1287 1288
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1289
				goto out_unlock;
L
Linus Torvalds 已提交
1290
			}
1291
			context[len] = '\0';
L
Linus Torvalds 已提交
1292 1293 1294 1295 1296 1297 1298
			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
1299
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1300
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1301 1302
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1303
				goto out_unlock;
L
Linus Torvalds 已提交
1304 1305 1306 1307 1308
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1309
			rc = security_context_to_sid_default(context, rc, &sid,
1310 1311
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1312
			if (rc) {
1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325
				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
1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343
				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);
1344 1345
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1346
		if (rc)
1347
			goto out_unlock;
L
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1348 1349
		isec->sid = sid;
		break;
1350 1351 1352
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1353
	default:
1354
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1355 1356
		isec->sid = sbsec->sid;

1357
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1358
			if (opt_dentry) {
L
Linus Torvalds 已提交
1359
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1360
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1361 1362 1363
							  isec->sclass,
							  &sid);
				if (rc)
1364
					goto out_unlock;
L
Linus Torvalds 已提交
1365 1366 1367 1368 1369 1370 1371 1372
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1373 1374
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407
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
1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420
/*
 * 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);
}

1421
/*
1422
 * Check permission between a pair of tasks, e.g. signal checks,
1423 1424
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1425
 * - this uses the default subjective creds of tsk1
1426 1427 1428
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1429 1430
			 u32 perms)
{
1431 1432
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1433

1434 1435 1436 1437 1438
	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
1439 1440
}

1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456
/*
 * 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);
}

1457 1458 1459 1460
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1461
/* Check whether a task is allowed to use a capability. */
1462
static int cred_has_capability(const struct cred *cred,
1463
			       int cap, int audit)
L
Linus Torvalds 已提交
1464
{
1465
	struct common_audit_data ad;
1466
	struct av_decision avd;
1467
	u16 sclass;
1468
	u32 sid = cred_sid(cred);
1469
	u32 av = CAP_TO_MASK(cap);
1470
	int rc;
L
Linus Torvalds 已提交
1471

1472
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1473 1474
	ad.u.cap = cap;

1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485
	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();
1486
		return -EINVAL;
1487
	}
1488

1489
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1490 1491 1492 1493 1494
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1495
	return rc;
L
Linus Torvalds 已提交
1496 1497 1498 1499 1500 1501
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1502
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1503

1504
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1505 1506 1507 1508 1509 1510
			    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). */
1511
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1512 1513
			  struct inode *inode,
			  u32 perms,
1514 1515
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1516 1517
{
	struct inode_security_struct *isec;
1518
	u32 sid;
L
Linus Torvalds 已提交
1519

1520 1521
	validate_creds(cred);

1522
	if (unlikely(IS_PRIVATE(inode)))
1523 1524
		return 0;

1525
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1526 1527
	isec = inode->i_security;

1528
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1529 1530 1531 1532 1533
}

/* 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. */
1534
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1535 1536 1537 1538
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1539
	struct common_audit_data ad;
1540

1541
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555
	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;

1556
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1557
	ad.u.path = *path;
1558
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568
}

/* 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. */
1569 1570 1571
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1572 1573
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1574
	struct inode *inode = file_inode(file);
1575
	struct common_audit_data ad;
1576
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1577 1578
	int rc;

1579
	ad.type = LSM_AUDIT_DATA_PATH;
1580
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1581

1582 1583
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1584 1585 1586 1587
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1588
			goto out;
L
Linus Torvalds 已提交
1589 1590 1591
	}

	/* av is zero if only checking access to the descriptor. */
1592
	rc = 0;
L
Linus Torvalds 已提交
1593
	if (av)
1594
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1595

1596 1597
out:
	return rc;
L
Linus Torvalds 已提交
1598 1599 1600 1601 1602 1603 1604
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1605
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1606 1607
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1608
	u32 sid, newsid;
1609
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1610 1611 1612 1613 1614
	int rc;

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

1615 1616 1617
	sid = tsec->sid;
	newsid = tsec->create_sid;

1618
	ad.type = LSM_AUDIT_DATA_DENTRY;
1619
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1620

1621
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1622 1623 1624 1625 1626
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1627
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1628 1629
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1630 1631 1632 1633
		if (rc)
			return rc;
	}

1634
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1635 1636 1637 1638 1639 1640 1641 1642
	if (rc)
		return rc;

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

1643 1644 1645 1646
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1647
	u32 sid = task_sid(ctx);
1648

1649
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1650 1651
}

1652 1653 1654
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1655 1656 1657 1658 1659 1660 1661 1662

/* 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;
1663
	struct common_audit_data ad;
1664
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1665 1666 1667 1668 1669 1670
	u32 av;
	int rc;

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

1671
	ad.type = LSM_AUDIT_DATA_DENTRY;
1672
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1673 1674 1675

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1676
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690
	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
1691 1692
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1693 1694 1695
		return 0;
	}

1696
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1697 1698 1699 1700 1701 1702 1703 1704 1705
	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;
1706
	struct common_audit_data ad;
1707
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1708 1709 1710 1711 1712 1713 1714 1715 1716
	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;

1717
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1718

1719
	ad.u.dentry = old_dentry;
1720
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1721 1722 1723
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1724
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1725 1726 1727 1728
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1729
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1730 1731 1732 1733 1734
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1735
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1736 1737 1738
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1739
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744
	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);
1745
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1746 1747 1748 1749 1750 1751 1752 1753 1754 1755
				  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. */
1756
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1757 1758
			       struct super_block *sb,
			       u32 perms,
1759
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1760 1761
{
	struct superblock_security_struct *sbsec;
1762
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1763 1764

	sbsec = sb->s_security;
1765
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1766 1767 1768 1769 1770 1771 1772
}

/* 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
1773
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795
		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;
}

1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818
/* 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
1819
/*
1820
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1821 1822
 * open permission.
 */
1823
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1824
{
1825
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1826

1827 1828 1829
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1830 1831 1832
	return av;
}

L
Linus Torvalds 已提交
1833 1834
/* Hook functions begin here. */

1835
static int selinux_ptrace_access_check(struct task_struct *child,
1836
				     unsigned int mode)
L
Linus Torvalds 已提交
1837 1838 1839
{
	int rc;

1840
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1841 1842 1843
	if (rc)
		return rc;

1844
	if (mode & PTRACE_MODE_READ) {
1845 1846 1847
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1848 1849
	}

1850
	return current_has_perm(child, PROCESS__PTRACE);
1851 1852 1853 1854 1855 1856
}

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

1857
	rc = cap_ptrace_traceme(parent);
1858 1859 1860 1861
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1862 1863 1864
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1865
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1866 1867 1868
{
	int error;

1869
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1870 1871 1872
	if (error)
		return error;

1873
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1874 1875
}

D
David Howells 已提交
1876 1877 1878 1879
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
1880 1881 1882
{
	int error;

1883
	error = cap_capset(new, old,
D
David Howells 已提交
1884
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1885 1886 1887
	if (error)
		return error;

D
David Howells 已提交
1888
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1889 1890
}

1891 1892 1893 1894 1895 1896 1897 1898 1899 1900
/*
 * (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.
 */

1901 1902
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1903 1904 1905
{
	int rc;

1906
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1907 1908 1909
	if (rc)
		return rc;

1910
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1911 1912 1913 1914
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1915
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1916 1917 1918 1919 1920 1921
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1922 1923 1924 1925 1926
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1927
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1928 1929 1930 1931
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1932
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1933 1934 1935 1936
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1937 1938 1939 1940 1941 1942
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1943 1944
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1945
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1946 1947
}

1948
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1949 1950 1951 1952
{
	int rc;

	switch (type) {
1953 1954
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1955 1956
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1957 1958 1959 1960
	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:
1961 1962
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1963 1964 1965 1966 1967
	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 */
1968 1969 1970
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982
	}
	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.
 */
1983
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1984 1985 1986
{
	int rc, cap_sys_admin = 0;

1987
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1988
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1989 1990 1991
	if (rc == 0)
		cap_sys_admin = 1;

1992
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1993 1994 1995 1996
}

/* binprm security operations */

1997
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1998
{
1999 2000
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2001
	struct inode_security_struct *isec;
2002
	struct common_audit_data ad;
A
Al Viro 已提交
2003
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2004 2005
	int rc;

2006
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2007 2008 2009
	if (rc)
		return rc;

2010 2011 2012
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2013 2014
		return 0;

2015 2016
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2017 2018 2019
	isec = inode->i_security;

	/* Default to the current task SID. */
2020 2021
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2022

2023
	/* Reset fs, key, and sock SIDs on execve. */
2024 2025 2026
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2027

2028 2029
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2030
		/* Reset exec SID on execve. */
2031
		new_tsec->exec_sid = 0;
2032 2033 2034 2035 2036 2037 2038

		/*
		 * 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
2039 2040
	} else {
		/* Check for a default transition on this program. */
2041
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2042 2043
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2044 2045 2046 2047
		if (rc)
			return rc;
	}

2048
	ad.type = LSM_AUDIT_DATA_PATH;
2049
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2050

2051 2052
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2053
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2054

2055 2056
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2057 2058 2059 2060 2061
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2062
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2063 2064 2065 2066
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2067
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2068 2069 2070 2071
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089
		/* 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();
2090
			tracer = ptrace_parent(current);
2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104
			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
2105

2106 2107
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2108 2109 2110 2111 2112
	}

	return 0;
}

2113
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2114
{
2115
	const struct task_security_struct *tsec = current_security();
2116
	u32 sid, osid;
L
Linus Torvalds 已提交
2117 2118
	int atsecure = 0;

2119 2120 2121 2122
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2123 2124 2125
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2126
		atsecure = avc_has_perm(osid, sid,
2127 2128
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2129 2130
	}

2131
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2132 2133
}

A
Al Viro 已提交
2134 2135 2136 2137 2138
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
2139
/* Derived from fs/exec.c:flush_old_files. */
2140 2141
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2142 2143
{
	struct file *file, *devnull = NULL;
2144
	struct tty_struct *tty;
2145
	int drop_tty = 0;
A
Al Viro 已提交
2146
	unsigned n;
L
Linus Torvalds 已提交
2147

2148
	tty = get_current_tty();
L
Linus Torvalds 已提交
2149
	if (tty) {
N
Nick Piggin 已提交
2150
		spin_lock(&tty_files_lock);
2151
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2152
			struct tty_file_private *file_priv;
2153

L
Linus Torvalds 已提交
2154
			/* Revalidate access to controlling tty.
2155
			   Use path_has_perm on the tty path directly rather
L
Linus Torvalds 已提交
2156 2157 2158
			   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
2159 2160 2161
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2162
			if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2163
				drop_tty = 1;
L
Linus Torvalds 已提交
2164
		}
N
Nick Piggin 已提交
2165
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2166
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2167
	}
2168 2169 2170
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2171 2172

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2173 2174 2175
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2176

A
Al Viro 已提交
2177
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2178 2179 2180 2181 2182 2183 2184
	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
2185
		fput(devnull);
L
Linus Torvalds 已提交
2186 2187
}

2188 2189 2190 2191
/*
 * 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
2192
{
2193 2194 2195
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2196

2197 2198 2199
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2200

2201 2202
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2203

2204 2205
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2206

2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219
	/* 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) {
2220 2221
		/* protect against do_prlimit() */
		task_lock(current);
2222 2223 2224 2225
		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
2226
		}
2227 2228
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2229 2230 2231 2232
	}
}

/*
2233 2234
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2235
 */
2236
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2237
{
2238
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2239
	struct itimerval itimer;
2240
	u32 osid, sid;
L
Linus Torvalds 已提交
2241 2242
	int rc, i;

2243 2244 2245 2246
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2247 2248
		return;

2249 2250 2251 2252 2253 2254 2255 2256
	/* 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
2257 2258 2259 2260 2261
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2262 2263 2264 2265 2266
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2267 2268 2269
		spin_unlock_irq(&current->sighand->siglock);
	}

2270 2271
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2272
	read_lock(&tasklist_lock);
2273
	__wake_up_parent(current, current->real_parent);
2274
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298
}

/* 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)
{
2299 2300 2301
	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) ||
2302 2303
		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
2304 2305 2306 2307 2308 2309 2310
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2311
	} else
L
Linus Torvalds 已提交
2312 2313 2314 2315 2316
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2317 2318
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2319 2320 2321 2322 2323 2324
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2325
	} else
2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337
		*first = 0;

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

2338
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2339 2340 2341 2342
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2343
	int open_quote = 0;
L
Linus Torvalds 已提交
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358

	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 {
2359 2360 2361 2362
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2363 2364 2365
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2366
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2367 2368 2369 2370 2371 2372 2373
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2374
	strcpy(in_save, nosec_save);
2375
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2376 2377 2378 2379
out:
	return rc;
}

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
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;

2415
		if (flags[i] == SBLABEL_MNT)
2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464
			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;
}

2465
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2466
{
2467
	const struct cred *cred = current_cred();
2468
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2469 2470 2471 2472 2473 2474
	int rc;

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

2475 2476 2477 2478
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2479
	ad.type = LSM_AUDIT_DATA_DENTRY;
2480
	ad.u.dentry = sb->s_root;
2481
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2482 2483
}

2484
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2485
{
2486
	const struct cred *cred = current_cred();
2487
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2488

2489
	ad.type = LSM_AUDIT_DATA_DENTRY;
2490
	ad.u.dentry = dentry->d_sb->s_root;
2491
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2492 2493
}

A
Al Viro 已提交
2494
static int selinux_mount(const char *dev_name,
2495
			 struct path *path,
A
Al Viro 已提交
2496
			 const char *type,
2497 2498
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2499
{
2500
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2501 2502

	if (flags & MS_REMOUNT)
2503
		return superblock_has_perm(cred, path->dentry->d_sb,
2504
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2505
	else
E
Eric Paris 已提交
2506
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2507 2508 2509 2510
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2511
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2512

2513
	return superblock_has_perm(cred, mnt->mnt_sb,
2514
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528
}

/* 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);
}

2529
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2530 2531
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2532
{
2533
	const struct task_security_struct *tsec = current_security();
2534 2535
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2536
	u32 sid, newsid, clen;
2537
	int rc;
2538
	char *namep = NULL, *context;
2539 2540 2541 2542

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

2543 2544 2545
	sid = tsec->sid;
	newsid = tsec->create_sid;

2546 2547 2548
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2549
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2550
		rc = security_transition_sid(sid, dsec->sid,
2551
					     inode_mode_to_security_class(inode->i_mode),
2552
					     qstr, &newsid);
2553 2554 2555 2556
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2557
			       __func__,
2558 2559 2560 2561 2562
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2563
	/* Possibly defer initialization to selinux_complete_init. */
2564
	if (sbsec->flags & SE_SBINITIALIZED) {
2565 2566 2567 2568 2569
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2570

2571
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2572 2573
		return -EOPNOTSUPP;

2574
	if (name) {
2575
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2576 2577 2578 2579
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2580

2581
	if (value && len) {
2582
		rc = security_sid_to_context_force(newsid, &context, &clen);
2583 2584 2585 2586 2587 2588
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2589 2590 2591 2592 2593
	}

	return 0;
}

A
Al Viro 已提交
2594
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613
{
	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);
}

2614
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2615 2616 2617 2618 2619 2620 2621 2622 2623
{
	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
2624
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2625 2626 2627 2628 2629
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2630
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2631 2632 2633 2634 2635 2636
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2637 2638
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2639
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2640 2641 2642 2643
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2644
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2645

E
Eric Paris 已提交
2646
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2647 2648
}

2649 2650 2651
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2652
{
2653
	struct common_audit_data ad;
2654 2655 2656
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2657
	ad.type = LSM_AUDIT_DATA_INODE;
2658 2659 2660 2661 2662 2663 2664 2665 2666
	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;
}

2667
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2668
{
2669
	const struct cred *cred = current_cred();
2670 2671
	u32 perms;
	bool from_access;
2672
	unsigned flags = mask & MAY_NOT_BLOCK;
2673 2674 2675 2676 2677
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2678

2679
	from_access = mask & MAY_ACCESS;
2680 2681
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2682 2683
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2684 2685
		return 0;

2686
	validate_creds(cred);
2687

2688 2689
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2690 2691 2692

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

2693 2694 2695 2696 2697 2698 2699 2700 2701 2702
	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;

2703
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2704 2705 2706
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2707 2708 2709 2710
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2711
	const struct cred *cred = current_cred();
2712
	unsigned int ia_valid = iattr->ia_valid;
2713
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2714

2715 2716 2717 2718 2719 2720 2721
	/* 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
2722

2723 2724
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2725
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2726

2727
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2728 2729 2730
		av |= FILE__OPEN;

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

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2735
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2736 2737 2738 2739
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2740

E
Eric Paris 已提交
2741
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2742 2743
}

2744
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2745
{
2746 2747
	const struct cred *cred = current_cred();

2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
	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
2762
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2763 2764
}

2765 2766
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
2767 2768 2769 2770
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2771
	struct common_audit_data ad;
2772
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2773 2774
	int rc = 0;

2775 2776
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2777 2778

	sbsec = inode->i_sb->s_security;
2779
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2780 2781
		return -EOPNOTSUPP;

2782
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2783 2784
		return -EPERM;

2785
	ad.type = LSM_AUDIT_DATA_DENTRY;
2786
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2787

2788
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2789 2790 2791 2792 2793
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2794
	if (rc == -EINVAL) {
2795 2796 2797 2798 2799 2800 2801
		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 */
2802 2803 2804 2805 2806 2807 2808 2809 2810 2811
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2812 2813 2814 2815 2816
			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);

2817
			return rc;
2818
		}
2819 2820
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2821 2822 2823
	if (rc)
		return rc;

2824
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2825 2826 2827 2828
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2829
	rc = security_validate_transition(isec->sid, newsid, sid,
2830
					  isec->sclass);
L
Linus Torvalds 已提交
2831 2832 2833 2834 2835 2836 2837 2838 2839 2840
	if (rc)
		return rc;

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

2841
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2842
					const void *value, size_t size,
2843
					int flags)
L
Linus Torvalds 已提交
2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854
{
	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;
	}

2855
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2856
	if (rc) {
2857 2858 2859
		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
2860 2861 2862 2863 2864 2865 2866
		return;
	}

	isec->sid = newsid;
	return;
}

2867
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2868
{
2869 2870
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2871
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2872 2873
}

2874
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2875
{
2876 2877
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2878
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2879 2880
}

2881
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2882
{
2883 2884
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2885 2886 2887 2888 2889 2890

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

2891
/*
2892
 * Copy the inode security context value to the user.
2893 2894 2895
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2896
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2897
{
2898 2899 2900
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2901
	struct inode_security_struct *isec = inode->i_security;
2902

2903 2904
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2905

2906 2907 2908 2909 2910 2911 2912 2913 2914
	/*
	 * 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.
	 */
2915
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2916
				SECURITY_CAP_NOAUDIT);
2917 2918 2919 2920 2921
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2922 2923 2924 2925 2926 2927 2928 2929 2930 2931
	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
2932 2933 2934
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2935
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946
{
	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;

2947
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2948 2949 2950 2951
	if (rc)
		return rc;

	isec->sid = newsid;
2952
	isec->initialized = 1;
L
Linus Torvalds 已提交
2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963
	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;
}

2964 2965 2966 2967 2968 2969
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
2970 2971
/* file security operations */

2972
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2973
{
2974
	const struct cred *cred = current_cred();
A
Al Viro 已提交
2975
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
2976 2977 2978 2979 2980

	/* 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;

2981 2982
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2983 2984
}

2985 2986
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
2987
	struct inode *inode = file_inode(file);
2988 2989 2990 2991
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2992
	if (!mask)
2993 2994 2995
		/* No permission to check.  Existence test. */
		return 0;

2996 2997
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
2998
		/* No change since file_open check. */
2999 3000
		return 0;

3001 3002 3003
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016
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)
{
3017
	const struct cred *cred = current_cred();
3018
	int error = 0;
L
Linus Torvalds 已提交
3019

3020 3021 3022 3023 3024 3025 3026
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3027
	case FS_IOC_GETFLAGS:
3028
	/* fall through */
3029
	case FS_IOC_GETVERSION:
3030 3031
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3032

3033
	case FS_IOC_SETFLAGS:
3034
	/* fall through */
3035
	case FS_IOC_SETVERSION:
3036 3037 3038 3039 3040 3041 3042 3043 3044
		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
3045

3046 3047
	case KDSKBENT:
	case KDSKBSENT:
3048 3049
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3050 3051 3052 3053 3054 3055 3056 3057 3058
		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
3059 3060
}

3061 3062
static int default_noexec;

L
Linus Torvalds 已提交
3063 3064
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3065
	const struct cred *cred = current_cred();
D
David Howells 已提交
3066
	int rc = 0;
3067

3068 3069
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3070 3071 3072 3073 3074
		/*
		 * 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
3075
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3076
		if (rc)
D
David Howells 已提交
3077
			goto error;
L
Linus Torvalds 已提交
3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090
	}

	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;

3091
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3092
	}
D
David Howells 已提交
3093 3094 3095

error:
	return rc;
L
Linus Torvalds 已提交
3096 3097
}

3098
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3099
{
3100
	int rc = 0;
3101
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3102

3103 3104 3105 3106 3107 3108
	/*
	 * 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.
	 */
3109
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3110 3111
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3112 3113 3114 3115 3116
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3117 3118
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3119

3120 3121 3122
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133
	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)
{
3134
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3135 3136 3137 3138

	if (selinux_checkreqprot)
		prot = reqprot;

3139 3140
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3141
		int rc = 0;
3142 3143
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3144
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3145 3146 3147
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3148
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3149 3150 3151 3152 3153 3154 3155 3156
		} 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
3157
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3158
		}
3159 3160 3161
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3162 3163 3164 3165 3166 3167

	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)
{
3168 3169 3170
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3171 3172 3173 3174 3175
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3176
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3177 3178 3179
	int err = 0;

	switch (cmd) {
3180 3181
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3182
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3183
			break;
3184 3185 3186 3187 3188 3189 3190
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3191
	case F_GETOWNER_UIDS:
3192
		/* Just check FD__USE permission */
3193
		err = file_has_perm(cred, file, 0);
3194 3195 3196 3197
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3198
#if BITS_PER_LONG == 32
3199 3200 3201
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3202
#endif
3203
		err = file_has_perm(cred, file, FILE__LOCK);
3204
		break;
L
Linus Torvalds 已提交
3205 3206 3207 3208 3209 3210 3211 3212 3213 3214
	}

	return err;
}

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

	fsec = file->f_security;
3215
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3216 3217 3218 3219 3220 3221 3222

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3223
	struct file *file;
3224
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3225 3226 3227 3228
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3229
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3230 3231 3232 3233 3234 3235 3236 3237

	fsec = file->f_security;

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

3238
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3239 3240 3241 3242 3243
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3244 3245 3246
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3247 3248
}

3249
static int selinux_file_open(struct file *file, const struct cred *cred)
3250 3251 3252
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3253

3254
	fsec = file->f_security;
A
Al Viro 已提交
3255
	isec = file_inode(file)->i_security;
3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272
	/*
	 * 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.
	 */
3273
	return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3274 3275
}

L
Linus Torvalds 已提交
3276 3277 3278 3279
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3280
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3281 3282
}

3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297
/*
 * 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
3298 3299 3300 3301
/*
 * 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
3302
{
D
David Howells 已提交
3303
	struct task_security_struct *tsec = cred->security;
3304

3305 3306 3307 3308 3309
	/*
	 * 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);
3310
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3311 3312
	kfree(tsec);
}
L
Linus Torvalds 已提交
3313

D
David Howells 已提交
3314 3315 3316 3317 3318 3319 3320 3321
/*
 * 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
3322

D
David Howells 已提交
3323
	old_tsec = old->security;
L
Linus Torvalds 已提交
3324

D
David Howells 已提交
3325 3326 3327
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3328

D
David Howells 已提交
3329
	new->security = tsec;
L
Linus Torvalds 已提交
3330 3331 3332
	return 0;
}

3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343
/*
 * 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;
}

3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384
/*
 * 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;
3385
	return ret;
3386 3387
}

3388
static int selinux_kernel_module_request(char *kmod_name)
3389
{
3390 3391 3392 3393 3394
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3395
	ad.type = LSM_AUDIT_DATA_KMOD;
3396 3397 3398 3399
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3400 3401
}

L
Linus Torvalds 已提交
3402 3403
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3404
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3405 3406 3407 3408
}

static int selinux_task_getpgid(struct task_struct *p)
{
3409
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3410 3411 3412 3413
}

static int selinux_task_getsid(struct task_struct *p)
{
3414
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3415 3416
}

3417 3418
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3419
	*secid = task_sid(p);
3420 3421
}

L
Linus Torvalds 已提交
3422 3423 3424 3425
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3426
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3427 3428 3429
	if (rc)
		return rc;

3430
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3431 3432
}

3433 3434
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3435 3436
	int rc;

3437
	rc = cap_task_setioprio(p, ioprio);
3438 3439 3440
	if (rc)
		return rc;

3441
	return current_has_perm(p, PROCESS__SETSCHED);
3442 3443
}

3444 3445
static int selinux_task_getioprio(struct task_struct *p)
{
3446
	return current_has_perm(p, PROCESS__GETSCHED);
3447 3448
}

3449 3450
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3451
{
3452
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3453 3454 3455 3456

	/* 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
3457
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3458
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3459
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3460 3461 3462 3463

	return 0;
}

3464
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3465
{
3466 3467
	int rc;

3468
	rc = cap_task_setscheduler(p);
3469 3470 3471
	if (rc)
		return rc;

3472
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3473 3474 3475 3476
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3477
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3478 3479
}

3480 3481
static int selinux_task_movememory(struct task_struct *p)
{
3482
	return current_has_perm(p, PROCESS__SETSCHED);
3483 3484
}

3485 3486
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3487 3488 3489 3490 3491 3492 3493 3494
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3495
	if (secid)
3496 3497
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3498
	else
3499
		rc = current_has_perm(p, perm);
3500
	return rc;
L
Linus Torvalds 已提交
3501 3502 3503 3504
}

static int selinux_task_wait(struct task_struct *p)
{
3505
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3506 3507 3508 3509 3510 3511
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3512
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3513

3514
	isec->sid = sid;
L
Linus Torvalds 已提交
3515 3516 3517 3518
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3519
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3520
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3521 3522 3523 3524
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3525
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3526 3527 3528 3529 3530 3531 3532 3533
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3534 3535
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3536 3537
	ret = 0;

3538 3539 3540
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3541
	switch (ih->protocol) {
3542 3543
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3544

3545 3546
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3547 3548 3549 3550 3551 3552

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

3553 3554
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3555
		break;
3556 3557 3558 3559 3560 3561 3562 3563
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3564
		offset += ihlen;
3565
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3566
		if (uh == NULL)
3567
			break;
L
Linus Torvalds 已提交
3568

3569 3570
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3571 3572
		break;
	}
L
Linus Torvalds 已提交
3573

J
James Morris 已提交
3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584
	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;

3585 3586
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3587
		break;
3588
	}
J
James Morris 已提交
3589

3590 3591 3592
	default:
		break;
	}
L
Linus Torvalds 已提交
3593 3594 3595 3596 3597 3598 3599
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3600
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3601
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3602 3603 3604 3605
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3606
	__be16 frag_off;
L
Linus Torvalds 已提交
3607

3608
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3609 3610 3611 3612
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3613 3614
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3615 3616 3617 3618
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3619
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3620 3621 3622
	if (offset < 0)
		goto out;

3623 3624 3625
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3626 3627
	switch (nexthdr) {
	case IPPROTO_TCP: {
3628
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3629 3630 3631 3632 3633

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

3634 3635
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3636 3637 3638 3639 3640 3641 3642 3643 3644 3645
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3646 3647
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3648 3649 3650
		break;
	}

J
James Morris 已提交
3651 3652 3653 3654 3655 3656 3657
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3658 3659
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3660
		break;
3661
	}
J
James Morris 已提交
3662

L
Linus Torvalds 已提交
3663 3664 3665 3666 3667 3668 3669 3670 3671 3672
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3673
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3674
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3675
{
3676 3677
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3678

3679
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3680
	case PF_INET:
3681
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3682 3683
		if (ret)
			goto parse_error;
3684 3685
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3686
		goto okay;
L
Linus Torvalds 已提交
3687 3688 3689

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3690
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3691 3692
		if (ret)
			goto parse_error;
3693 3694
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3695
		goto okay;
L
Linus Torvalds 已提交
3696 3697
#endif	/* IPV6 */
	default:
3698 3699
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3700 3701
	}

3702 3703 3704 3705
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3706
	return ret;
3707 3708 3709 3710 3711

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3712 3713
}

3714
/**
3715
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3716
 * @skb: the packet
3717
 * @family: protocol family
3718
 * @sid: the packet's peer label SID
3719 3720
 *
 * Description:
3721 3722 3723 3724 3725 3726
 * 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.
3727 3728
 *
 */
3729
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3730
{
3731
	int err;
3732 3733
	u32 xfrm_sid;
	u32 nlbl_sid;
3734
	u32 nlbl_type;
3735

3736 3737 3738 3739 3740 3741
	err = selinux_skb_xfrm_sid(skb, &xfrm_sid);
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3742

3743 3744 3745 3746 3747
	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");
3748
		return -EACCES;
3749
	}
3750 3751

	return 0;
3752 3753
}

L
Linus Torvalds 已提交
3754
/* socket security operations */
3755

3756 3757
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3758
{
3759 3760 3761 3762 3763 3764 3765
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3766 3767
}

3768
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3769
{
3770
	struct sk_security_struct *sksec = sk->sk_security;
3771
	struct common_audit_data ad;
3772
	struct lsm_network_audit net = {0,};
3773
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3774

3775 3776
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3777

3778
	ad.type = LSM_AUDIT_DATA_NET;
3779 3780
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3781

3782
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3783 3784 3785 3786 3787
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3788
	const struct task_security_struct *tsec = current_security();
3789
	u32 newsid;
3790
	u16 secclass;
3791
	int rc;
L
Linus Torvalds 已提交
3792 3793

	if (kern)
3794
		return 0;
3795 3796

	secclass = socket_type_to_security_class(family, type, protocol);
3797 3798 3799 3800
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3801
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3802 3803
}

V
Venkat Yekkirala 已提交
3804 3805
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3806
{
3807
	const struct task_security_struct *tsec = current_security();
3808
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3809
	struct sk_security_struct *sksec;
3810 3811
	int err = 0;

3812 3813
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3814 3815
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3816 3817 3818 3819 3820
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3821

L
Linus Torvalds 已提交
3822 3823
	isec->initialized = 1;

3824 3825 3826
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3827
		sksec->sclass = isec->sclass;
3828
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3829 3830
	}

V
Venkat Yekkirala 已提交
3831
	return err;
L
Linus Torvalds 已提交
3832 3833 3834 3835 3836 3837 3838 3839
}

/* 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)
{
3840
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3841 3842 3843
	u16 family;
	int err;

3844
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3845 3846 3847 3848 3849
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3850 3851
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3852
	 */
3853
	family = sk->sk_family;
L
Linus Torvalds 已提交
3854 3855
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3856
		struct sk_security_struct *sksec = sk->sk_security;
3857
		struct common_audit_data ad;
3858
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3859 3860 3861
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3862
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873

		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;
		}

3874 3875 3876 3877 3878 3879
		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
3880 3881
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3882 3883
				if (err)
					goto out;
3884
				ad.type = LSM_AUDIT_DATA_NET;
3885 3886 3887
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
3888 3889
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3890 3891 3892 3893
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3894
		}
3895

3896
		switch (sksec->sclass) {
3897
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3898 3899
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3900

3901
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3902 3903
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3904 3905 3906 3907 3908

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3909 3910 3911 3912
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3913

3914
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3915 3916
		if (err)
			goto out;
3917

3918
		ad.type = LSM_AUDIT_DATA_NET;
3919 3920 3921
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
3922 3923

		if (family == PF_INET)
3924
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
3925
		else
3926
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3927

3928 3929
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3930 3931 3932 3933 3934 3935 3936 3937 3938
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3939
	struct sock *sk = sock->sk;
3940
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3941 3942
	int err;

3943
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3944 3945 3946 3947
	if (err)
		return err;

	/*
J
James Morris 已提交
3948
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3949
	 */
3950 3951
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3952
		struct common_audit_data ad;
3953
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3954 3955 3956
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3957
		u32 sid, perm;
L
Linus Torvalds 已提交
3958 3959 3960

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3961
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3962 3963 3964 3965
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3966
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3967 3968 3969 3970
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3971
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3972 3973 3974
		if (err)
			goto out;

3975
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3976 3977
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3978
		ad.type = LSM_AUDIT_DATA_NET;
3979 3980 3981
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
3982
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3983 3984 3985 3986
		if (err)
			goto out;
	}

3987 3988
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3989 3990 3991 3992 3993 3994
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3995
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3996 3997 3998 3999 4000 4001 4002 4003
}

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

4004
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018
	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,
4019
				  int size)
L
Linus Torvalds 已提交
4020
{
4021
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4022 4023 4024 4025 4026
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4027
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4028 4029 4030 4031
}

static int selinux_socket_getsockname(struct socket *sock)
{
4032
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4033 4034 4035 4036
}

static int selinux_socket_getpeername(struct socket *sock)
{
4037
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4038 4039
}

4040
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4041
{
4042 4043
	int err;

4044
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4045 4046 4047 4048
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4049 4050 4051 4052 4053
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4054
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4055 4056 4057 4058
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4059
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4060 4061
}

4062 4063
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4064 4065
					      struct sock *newsk)
{
4066 4067
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4068
	struct sk_security_struct *sksec_new = newsk->sk_security;
4069
	struct common_audit_data ad;
4070
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4071 4072
	int err;

4073
	ad.type = LSM_AUDIT_DATA_NET;
4074 4075
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4076

4077 4078
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4079 4080 4081 4082 4083
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4084 4085 4086 4087 4088
	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;
4089

4090 4091 4092 4093
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4094 4095 4096 4097 4098
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4099 4100
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4101
	struct common_audit_data ad;
4102
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4103

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

4108 4109
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4110 4111
}

4112 4113
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4114
				    struct common_audit_data *ad)
4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134
{
	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);
}

4135
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4136
				       u16 family)
4137
{
4138
	int err = 0;
4139 4140
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4141
	struct common_audit_data ad;
4142
	struct lsm_network_audit net = {0,};
4143 4144
	char *addrp;

4145
	ad.type = LSM_AUDIT_DATA_NET;
4146 4147 4148
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4149 4150 4151
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4152

4153
	if (selinux_secmark_enabled()) {
4154
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4155
				   PACKET__RECV, &ad);
4156 4157 4158
		if (err)
			return err;
	}
4159

4160 4161 4162 4163
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4164

4165 4166 4167 4168 4169
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4170
	int err;
4171
	struct sk_security_struct *sksec = sk->sk_security;
4172 4173
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4174
	struct common_audit_data ad;
4175
	struct lsm_network_audit net = {0,};
4176
	char *addrp;
4177 4178
	u8 secmark_active;
	u8 peerlbl_active;
4179 4180

	if (family != PF_INET && family != PF_INET6)
4181
		return 0;
4182 4183

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4184
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4185 4186
		family = PF_INET;

4187 4188 4189 4190
	/* 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. */
4191
	if (!selinux_policycap_netpeer)
4192 4193 4194 4195 4196 4197 4198
		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;

4199
	ad.type = LSM_AUDIT_DATA_NET;
4200 4201 4202
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4203
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4204
	if (err)
4205
		return err;
4206

4207
	if (peerlbl_active) {
4208 4209 4210
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4211 4212
		if (err)
			return err;
4213
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4214
					       peer_sid, &ad);
4215 4216
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4217
			return err;
4218
		}
4219 4220
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4221 4222
		if (err)
			selinux_netlbl_err(skb, err, 0);
4223 4224
	}

4225
	if (secmark_active) {
4226 4227 4228 4229 4230 4231
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4232
	return err;
L
Linus Torvalds 已提交
4233 4234
}

C
Catherine Zhang 已提交
4235 4236
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4237 4238 4239 4240
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4241
	struct sk_security_struct *sksec = sock->sk->sk_security;
4242
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4243

4244 4245
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4246
		peer_sid = sksec->peer_sid;
4247 4248
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4249

C
Catherine Zhang 已提交
4250
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4251
	if (err)
4252
		return err;
L
Linus Torvalds 已提交
4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268

	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;
}

4269
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4270
{
4271
	u32 peer_secid = SECSID_NULL;
4272
	u16 family;
C
Catherine Zhang 已提交
4273

4274 4275 4276 4277 4278
	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)
4279 4280 4281 4282 4283
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4284
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4285
	else if (skb)
4286
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4287

4288
out:
4289
	*secid = peer_secid;
4290 4291 4292
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4293 4294
}

A
Al Viro 已提交
4295
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4296
{
4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308
	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
4309 4310 4311 4312
}

static void selinux_sk_free_security(struct sock *sk)
{
4313 4314 4315 4316 4317
	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
4318 4319
}

4320
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4321
{
4322 4323
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4324

4325 4326 4327
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4328

4329
	selinux_netlbl_sk_security_reset(newsksec);
4330 4331
}

V
Venkat Yekkirala 已提交
4332
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4333
{
4334
	if (!sk)
V
Venkat Yekkirala 已提交
4335
		*secid = SECINITSID_ANY_SOCKET;
4336 4337
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4338

V
Venkat Yekkirala 已提交
4339
		*secid = sksec->sid;
4340
	}
4341 4342
}

4343
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4344 4345 4346 4347
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4348 4349 4350
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4351
	sksec->sclass = isec->sclass;
4352 4353
}

4354 4355
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4356 4357 4358
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4359
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4360
	u32 newsid;
4361 4362
	u32 peersid;

4363 4364 4365 4366 4367
	/* 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);
4368 4369
	if (err)
		return err;
4370 4371
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4372
		req->peer_secid = SECSID_NULL;
4373 4374 4375 4376 4377 4378
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4379 4380
	}

4381
	return selinux_netlbl_inet_conn_request(req, family);
4382 4383
}

4384 4385
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4386 4387 4388 4389
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4390
	newsksec->peer_sid = req->peer_secid;
4391 4392 4393 4394
	/* 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. */
4395

P
Paul Moore 已提交
4396 4397
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4398
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4399 4400
}

4401
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4402
{
4403
	u16 family = sk->sk_family;
4404 4405
	struct sk_security_struct *sksec = sk->sk_security;

4406 4407 4408 4409 4410
	/* 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);
4411 4412
}

4413 4414 4415 4416 4417
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438
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);
}

4439 4440
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4441
{
4442
	fl->flowi_secid = req->secid;
4443 4444
}

4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462
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);
}

4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477
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);
}

4478
static int selinux_tun_dev_attach_queue(void *security)
4479
{
4480 4481 4482 4483 4484 4485 4486 4487 4488
	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;
4489 4490 4491 4492 4493 4494 4495 4496 4497
	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 */

4498
	sksec->sid = tunsec->sid;
4499
	sksec->sclass = SECCLASS_TUN_SOCKET;
4500 4501

	return 0;
4502 4503
}

4504
static int selinux_tun_dev_open(void *security)
4505
{
4506
	struct tun_security_struct *tunsec = security;
4507 4508 4509
	u32 sid = current_sid();
	int err;

4510
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4511 4512 4513 4514 4515 4516 4517
			   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;
4518
	tunsec->sid = sid;
4519 4520 4521 4522

	return 0;
}

L
Linus Torvalds 已提交
4523 4524 4525 4526 4527
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4528
	struct sk_security_struct *sksec = sk->sk_security;
4529

4530
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4531 4532 4533
		err = -EINVAL;
		goto out;
	}
4534
	nlh = nlmsg_hdr(skb);
4535

4536
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4537 4538
	if (err) {
		if (err == -EINVAL) {
4539
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4540 4541
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4542
				  nlh->nlmsg_type, sksec->sclass);
4543
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4544 4545 4546 4547 4548 4549 4550 4551 4552
				err = 0;
		}

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

4553
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4554 4555 4556 4557 4558 4559
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4560 4561
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4562
{
4563
	int err;
4564 4565
	char *addrp;
	u32 peer_sid;
4566
	struct common_audit_data ad;
4567
	struct lsm_network_audit net = {0,};
4568
	u8 secmark_active;
4569
	u8 netlbl_active;
4570
	u8 peerlbl_active;
4571

4572 4573
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4574

4575
	secmark_active = selinux_secmark_enabled();
4576 4577
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4578 4579
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4580

4581 4582 4583
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4584
	ad.type = LSM_AUDIT_DATA_NET;
4585 4586 4587
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4588 4589 4590
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4591 4592 4593 4594 4595
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4596
			return NF_DROP;
4597 4598
		}
	}
4599 4600 4601 4602 4603 4604

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

4605 4606 4607 4608 4609 4610 4611 4612
	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;

4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635
	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 */

4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666
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);
}

4667 4668
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4669
						u16 family)
4670 4671 4672
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4673
	struct common_audit_data ad;
4674
	struct lsm_network_audit net = {0,};
4675 4676
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4677

4678 4679 4680 4681
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4682
	ad.type = LSM_AUDIT_DATA_NET;
4683 4684 4685
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4686 4687 4688
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4689
	if (selinux_secmark_enabled())
4690
		if (avc_has_perm(sksec->sid, skb->secmark,
4691
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4692
			return NF_DROP_ERR(-ECONNREFUSED);
4693

4694 4695
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4696 4697

	return NF_ACCEPT;
4698 4699
}

4700 4701
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4702
{
4703 4704
	u32 secmark_perm;
	u32 peer_sid;
4705
	struct sock *sk;
4706
	struct common_audit_data ad;
4707
	struct lsm_network_audit net = {0,};
4708 4709 4710
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4711

4712 4713 4714 4715
	/* 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. */
4716
	if (!selinux_policycap_netpeer)
4717
		return selinux_ip_postroute_compat(skb, ifindex, family);
4718
#ifdef CONFIG_XFRM
4719 4720 4721 4722 4723 4724
	/* 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
4725
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4726
		return NF_ACCEPT;
4727
#endif
4728 4729 4730 4731 4732
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4733 4734 4735 4736
	/* 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 */
4737
	sk = skb->sk;
4738
	if (sk == NULL) {
4739 4740
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4741
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4742
				return NF_DROP;
4743 4744
		} else {
			secmark_perm = PACKET__SEND;
4745
			peer_sid = SECINITSID_KERNEL;
4746
		}
4747
	} else {
4748 4749 4750 4751
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4752

4753
	ad.type = LSM_AUDIT_DATA_NET;
4754 4755 4756
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4757
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4758
		return NF_DROP;
4759

4760 4761 4762
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4763
			return NF_DROP_ERR(-ECONNREFUSED);
4764 4765 4766 4767 4768 4769

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4770
			return NF_DROP;
4771 4772
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4773
			return NF_DROP_ERR(-ECONNREFUSED);
4774 4775

		if (sel_netnode_sid(addrp, family, &node_sid))
4776
			return NF_DROP;
4777 4778
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4779
			return NF_DROP_ERR(-ECONNREFUSED);
4780
	}
4781

4782
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4783 4784
}

4785 4786 4787 4788 4789
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
4790
{
4791
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4792 4793 4794
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4795 4796 4797 4798 4799
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
4800
{
4801
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4802 4803 4804 4805 4806 4807 4808 4809 4810
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4811
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4812 4813 4814
	if (err)
		return err;

4815
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4816 4817 4818 4819 4820 4821 4822
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4823
	u32 sid;
L
Linus Torvalds 已提交
4824

J
James Morris 已提交
4825
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4826 4827 4828
	if (!isec)
		return -ENOMEM;

4829
	sid = task_sid(task);
L
Linus Torvalds 已提交
4830
	isec->sclass = sclass;
4831
	isec->sid = sid;
L
Linus Torvalds 已提交
4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847
	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
4848
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4849 4850 4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866
	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,
4867
			u32 perms)
L
Linus Torvalds 已提交
4868 4869
{
	struct ipc_security_struct *isec;
4870
	struct common_audit_data ad;
4871
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4872 4873 4874

	isec = ipc_perms->security;

4875
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4876 4877
	ad.u.ipc_id = ipc_perms->key;

4878
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894
}

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;
4895
	struct common_audit_data ad;
4896
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4897 4898 4899 4900 4901 4902 4903 4904
	int rc;

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

	isec = msq->q_perm.security;

4905
	ad.type = LSM_AUDIT_DATA_IPC;
4906
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4907

4908
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924
			  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;
4925
	struct common_audit_data ad;
4926
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4927 4928 4929

	isec = msq->q_perm.security;

4930
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4931 4932
	ad.u.ipc_id = msq->q_perm.key;

4933
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4934 4935 4936 4937 4938 4939 4940 4941
			    MSGQ__ASSOCIATE, &ad);
}

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

4942
	switch (cmd) {
L
Linus Torvalds 已提交
4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960
	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;
	}

4961
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4962 4963 4964 4965 4966 4967 4968
	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;
4969
	struct common_audit_data ad;
4970
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982 4983
	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
		 */
4984
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4985
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4986 4987 4988 4989
		if (rc)
			return rc;
	}

4990
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4991 4992 4993
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4994
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4995 4996 4997
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4998 4999
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5000 5001
	if (!rc)
		/* Can the message be put in the queue? */
5002 5003
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5004 5005 5006 5007 5008 5009 5010 5011 5012 5013

	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;
5014
	struct common_audit_data ad;
5015
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5016 5017 5018 5019 5020
	int rc;

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

5021
	ad.type = LSM_AUDIT_DATA_IPC;
5022
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5023

5024
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5025 5026
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5027
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5028 5029 5030 5031 5032 5033 5034 5035
				  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;
5036
	struct common_audit_data ad;
5037
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5038 5039 5040 5041 5042 5043 5044 5045
	int rc;

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

	isec = shp->shm_perm.security;

5046
	ad.type = LSM_AUDIT_DATA_IPC;
5047
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5048

5049
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065
			  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;
5066
	struct common_audit_data ad;
5067
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5068 5069 5070

	isec = shp->shm_perm.security;

5071
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5072 5073
	ad.u.ipc_id = shp->shm_perm.key;

5074
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5075 5076 5077 5078 5079 5080 5081 5082 5083
			    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;

5084
	switch (cmd) {
L
Linus Torvalds 已提交
5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106
	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;
	}

5107
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120
	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;

5121
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5122 5123 5124 5125 5126 5127
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5128
	struct common_audit_data ad;
5129
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5130 5131 5132 5133 5134 5135 5136 5137
	int rc;

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

	isec = sma->sem_perm.security;

5138
	ad.type = LSM_AUDIT_DATA_IPC;
5139
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5140

5141
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157
			  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;
5158
	struct common_audit_data ad;
5159
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5160 5161 5162

	isec = sma->sem_perm.security;

5163
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5164 5165
	ad.u.ipc_id = sma->sem_perm.key;

5166
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5167 5168 5169 5170 5171 5172 5173 5174 5175
			    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;

5176
	switch (cmd) {
L
Linus Torvalds 已提交
5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207
	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;
	}

5208
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221
	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;

5222
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237
}

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;

5238
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5239 5240
}

5241 5242 5243 5244 5245 5246
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5247
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5248 5249 5250 5251 5252 5253
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5254
			       char *name, char **value)
L
Linus Torvalds 已提交
5255
{
5256
	const struct task_security_struct *__tsec;
5257
	u32 sid;
L
Linus Torvalds 已提交
5258
	int error;
5259
	unsigned len;
L
Linus Torvalds 已提交
5260 5261

	if (current != p) {
5262
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5263 5264 5265 5266
		if (error)
			return error;
	}

5267 5268
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5269 5270

	if (!strcmp(name, "current"))
5271
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5272
	else if (!strcmp(name, "prev"))
5273
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5274
	else if (!strcmp(name, "exec"))
5275
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5276
	else if (!strcmp(name, "fscreate"))
5277
		sid = __tsec->create_sid;
5278
	else if (!strcmp(name, "keycreate"))
5279
		sid = __tsec->keycreate_sid;
5280
	else if (!strcmp(name, "sockcreate"))
5281
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5282
	else
5283 5284
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5285 5286 5287 5288

	if (!sid)
		return 0;

5289 5290 5291 5292
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5293 5294 5295 5296

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5297 5298 5299 5300 5301 5302
}

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
5303
	struct task_struct *tracer;
D
David Howells 已提交
5304 5305
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320
	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"))
5321
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5322
	else if (!strcmp(name, "fscreate"))
5323
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5324
	else if (!strcmp(name, "keycreate"))
5325
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5326
	else if (!strcmp(name, "sockcreate"))
5327
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5328
	else if (!strcmp(name, "current"))
5329
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341
	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);
5342
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357
			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);

5358
				return error;
5359
			}
5360 5361 5362
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5363 5364 5365 5366
		if (error)
			return error;
	}

D
David Howells 已提交
5367 5368 5369 5370
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5371 5372 5373
	/* 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
5374
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5375 5376
	   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
5377 5378
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5379
		tsec->exec_sid = sid;
D
David Howells 已提交
5380
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5381
		tsec->create_sid = sid;
D
David Howells 已提交
5382
	} else if (!strcmp(name, "keycreate")) {
5383 5384
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5385
			goto abort_change;
5386
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5387
	} else if (!strcmp(name, "sockcreate")) {
5388
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5389 5390
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5391
		if (sid == 0)
D
David Howells 已提交
5392 5393 5394 5395
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5396
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5397 5398 5399
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5400
		}
L
Linus Torvalds 已提交
5401 5402 5403

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5404
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5405
		if (error)
D
David Howells 已提交
5406
			goto abort_change;
L
Linus Torvalds 已提交
5407 5408 5409

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5410
		ptsid = 0;
L
Linus Torvalds 已提交
5411
		task_lock(p);
5412
		tracer = ptrace_parent(p);
D
David Howells 已提交
5413 5414 5415 5416 5417 5418 5419
		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
5420
			if (error)
D
David Howells 已提交
5421
				goto abort_change;
L
Linus Torvalds 已提交
5422 5423
		}

D
David Howells 已提交
5424 5425 5426 5427 5428 5429 5430
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5431
	return size;
D
David Howells 已提交
5432 5433 5434 5435

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5436 5437
}

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

5443
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5444 5445 5446 5447
{
	return security_context_to_sid(secdata, seclen, secid);
}

5448 5449
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5450
	kfree(secdata);
5451 5452
}

5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475 5476 5477 5478
/*
 *	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;
}
5479 5480
#ifdef CONFIG_KEYS

D
David Howells 已提交
5481
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5482
			     unsigned long flags)
5483
{
D
David Howells 已提交
5484
	const struct task_security_struct *tsec;
5485 5486 5487 5488 5489 5490
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5491 5492 5493
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5494
	else
D
David Howells 已提交
5495
		ksec->sid = tsec->sid;
5496

5497
	k->security = ksec;
5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509
	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
5510 5511
				  const struct cred *cred,
				  key_perm_t perm)
5512 5513 5514
{
	struct key *key;
	struct key_security_struct *ksec;
5515
	u32 sid;
5516 5517 5518 5519 5520 5521 5522

	/* 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
5523
	sid = cred_sid(cred);
5524 5525 5526 5527 5528

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5529 5530
}

5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544
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;
}

5545 5546
#endif

L
Linus Torvalds 已提交
5547
static struct security_operations selinux_ops = {
5548 5549
	.name =				"selinux",

5550
	.ptrace_access_check =		selinux_ptrace_access_check,
5551
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5552
	.capget =			selinux_capget,
D
David Howells 已提交
5553
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5554 5555 5556 5557 5558 5559 5560 5561
	.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,

5562 5563 5564
	.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
5565 5566 5567 5568 5569
	.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,
5570
	.sb_remount =			selinux_sb_remount,
5571
	.sb_kern_mount =		selinux_sb_kern_mount,
5572
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5573 5574 5575
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5576
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5577
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5578 5579
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5580 5581 5582

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5583
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601
	.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,
5602 5603 5604
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5605
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5606 5607 5608 5609 5610

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5611 5612
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5613 5614 5615 5616 5617 5618 5619
	.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,

5620
	.file_open =			selinux_file_open,
5621

L
Linus Torvalds 已提交
5622
	.task_create =			selinux_task_create,
5623
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5624
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5625
	.cred_prepare =			selinux_cred_prepare,
5626
	.cred_transfer =		selinux_cred_transfer,
5627 5628
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5629
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5630 5631
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5632
	.task_getsid =			selinux_task_getsid,
5633
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5634
	.task_setnice =			selinux_task_setnice,
5635
	.task_setioprio =		selinux_task_setioprio,
5636
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5637 5638 5639
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5640
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5641 5642
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5643
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5644 5645

	.ipc_permission =		selinux_ipc_permission,
5646
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662 5663

	.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,

5664 5665
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5666 5667 5668 5669
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5670
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5671

5672 5673
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5674

5675
	.secid_to_secctx =		selinux_secid_to_secctx,
5676
	.secctx_to_secid =		selinux_secctx_to_secid,
5677
	.release_secctx =		selinux_release_secctx,
5678 5679 5680
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5681

5682
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698
	.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
5699 5700
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5701 5702
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5703
	.sk_clone_security =		selinux_sk_clone_security,
5704
	.sk_getsecid =			selinux_sk_getsecid,
5705 5706 5707
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5708
	.inet_conn_established =	selinux_inet_conn_established,
5709 5710 5711
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5712
	.req_classify_flow =		selinux_req_classify_flow,
5713 5714
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5715
	.tun_dev_create =		selinux_tun_dev_create,
5716
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5717
	.tun_dev_attach =		selinux_tun_dev_attach,
5718
	.tun_dev_open =			selinux_tun_dev_open,
5719
	.skb_owned_by =			selinux_skb_owned_by,
5720 5721 5722 5723 5724

#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
5725
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5726 5727
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5728
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5729
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5730
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5731 5732
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5733
#endif
5734 5735

#ifdef CONFIG_KEYS
5736 5737 5738
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5739
	.key_getsecurity =		selinux_key_getsecurity,
5740
#endif
5741 5742 5743 5744 5745 5746 5747

#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
5748 5749 5750 5751
};

static __init int selinux_init(void)
{
5752 5753 5754 5755 5756
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5757 5758 5759 5760 5761 5762 5763 5764
	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
5765
	cred_init_security();
L
Linus Torvalds 已提交
5766

5767 5768
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5769 5770
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5771
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5772 5773
	avc_init();

5774
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5775 5776
		panic("SELinux: Unable to register with kernel.\n");

5777
	if (selinux_enforcing)
5778
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5779
	else
5780
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5781

L
Linus Torvalds 已提交
5782 5783 5784
	return 0;
}

5785 5786 5787 5788 5789
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5790 5791
void selinux_complete_init(void)
{
5792
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5793 5794

	/* Set up any superblocks initialized prior to the policy load. */
5795
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5796
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5797 5798 5799 5800 5801 5802
}

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

5803
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5804

5805 5806 5807 5808
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5809
		.pf =		NFPROTO_IPV4,
5810 5811 5812 5813 5814 5815
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5816
		.pf =		NFPROTO_IPV4,
5817 5818
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5819 5820 5821 5822
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
5823
		.pf =		NFPROTO_IPV4,
5824 5825
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5826
	}
L
Linus Torvalds 已提交
5827 5828 5829 5830
};

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

5831 5832 5833 5834
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
5835
		.pf =		NFPROTO_IPV6,
5836 5837 5838 5839 5840 5841
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
5842
		.pf =		NFPROTO_IPV6,
5843 5844 5845
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5846 5847 5848 5849 5850 5851 5852 5853 5854 5855
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5856 5857 5858

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

5859 5860 5861
	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
5862 5863

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5864 5865 5866
	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
5867
#endif	/* IPV6 */
5868

L
Linus Torvalds 已提交
5869 5870 5871 5872 5873 5874 5875 5876 5877
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5878
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5879

5880
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5881
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5882
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5883 5884 5885 5886
#endif	/* IPV6 */
}
#endif

5887
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5888 5889 5890 5891 5892

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5893
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5894 5895

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5896 5897
static int selinux_disabled;

L
Linus Torvalds 已提交
5898 5899 5900 5901 5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912
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;
5913
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5914

5915
	reset_security_ops();
L
Linus Torvalds 已提交
5916

5917 5918 5919
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5920 5921 5922 5923 5924 5925 5926 5927 5928
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif