hooks.c 141.0 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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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>
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#include <linux/ext2_fs.h>
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#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/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 */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/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 "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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#define NUM_SEL_MNT_OPTS 5
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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	/* check if the old mount command had the same options */
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	if (sbsec->flags & SE_SBINITIALIZED)
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		if (!(sbsec->flags & flag) ||
		    (old_sid != new_sid))
			return 1;

	/* check if we were passed the same options twice,
	 * aka someone passed context=a,context=b
	 */
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	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
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			return 1;
	return 0;
}
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/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
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static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
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{
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	const struct cred *cred = current_cred();
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	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
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	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
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	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
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	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
565 566 567 568 569 570 571 572 573 574 575

	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
576 577
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
578
		goto out;
579
	}
L
Linus Torvalds 已提交
580

581 582 583 584 585 586 587 588 589 590 591
	/*
	 * 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)
	 */
592
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
593
	    && (num_opts == 0))
594
		goto out;
595

596 597 598 599 600 601 602
	/*
	 * 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;
603 604 605

		if (flags[i] == SE_SBLABELSUPP)
			continue;
606 607
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
608 609 610
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655
			       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
656
		}
657 658
	}

659
	if (sbsec->flags & SE_SBINITIALIZED) {
660
		/* previously mounted with options, but not on this attempt? */
661
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
662 663 664 665 666
			goto out_double_mount;
		rc = 0;
		goto out;
	}

667
	if (strcmp(sb->s_type->name, "proc") == 0)
668
		sbsec->flags |= SE_SBPROC;
669 670

	/* Determine the labeling behavior to use for this filesystem type. */
671
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
672 673
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
674
		       __func__, sb->s_type->name, rc);
675 676
		goto out;
	}
L
Linus Torvalds 已提交
677

678 679
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
680
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
681
		if (rc)
682
			goto out;
L
Linus Torvalds 已提交
683

684
		sbsec->sid = fscontext_sid;
685 686 687 688 689 690 691
	}

	/*
	 * 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.
	 */
692 693
	if (context_sid) {
		if (!fscontext_sid) {
694 695
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
696
			if (rc)
697 698
				goto out;
			sbsec->sid = context_sid;
699
		} else {
700 701
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
702
			if (rc)
703
				goto out;
704
		}
705 706
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
707

708
		sbsec->mntpoint_sid = context_sid;
709
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
710 711
	}

712
	if (rootcontext_sid) {
713 714
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
715
		if (rc)
716
			goto out;
717

718 719
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
720 721
	}

722 723 724 725 726 727
	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
728 729
		}

730 731
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
732
							     sbsec, cred);
733 734 735
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
736

737
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
738 739
	}

740
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
741
out:
742
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
743
	return rc;
744 745 746 747 748
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
749 750
}

751 752
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
753
{
754 755
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
756

757 758 759
	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
760

761 762
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
763
	 * mount options.  thus we can safely deal with this superblock later
764
	 */
765
	if (!ss_initialized)
766
		return;
767 768

	/* how can we clone if the old one wasn't set up?? */
769
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
770

771
	/* if fs is reusing a sb, just let its options stand... */
772
	if (newsbsec->flags & SE_SBINITIALIZED)
773 774
		return;

775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793
	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
794
	}
795 796 797 798 799
	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
800

801
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
802 803
	}

804 805 806 807
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

808 809
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
810
{
811
	char *p;
812 813
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
814
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
815

816
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
817

818 819 820 821
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
822

823 824
		if (!*p)
			continue;
L
Linus Torvalds 已提交
825

826
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
827

828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
		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;
880 881
		case Opt_labelsupport:
			break;
882 883 884 885
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
886 887 888

		}
	}
889

890 891 892 893 894 895 896 897 898 899 900
	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;
	}

901
	if (fscontext) {
902 903
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
904 905
	}
	if (context) {
906 907
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
908 909
	}
	if (rootcontext) {
910 911
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
912 913
	}
	if (defcontext) {
914 915
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
916 917
	}

918 919 920
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

921 922 923 924 925
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
926 927
	return rc;
}
928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954
/*
 * 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
955

A
Adrian Bunk 已提交
956 957
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
958 959 960 961 962
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
963 964 965 966 967 968
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
969 970 971 972 973 974 975 976 977 978 979 980 981 982

		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;
983 984 985 986
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
987 988
		default:
			BUG();
989
			return;
990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007
		};
		/* 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);
1008 1009 1010 1011
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1012
		return rc;
1013
	}
1014 1015 1016 1017 1018 1019 1020 1021

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044
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;
}

1045 1046 1047 1048 1049 1050 1051 1052 1053 1054
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
1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070
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:
1071 1072 1073 1074
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1075
		case SOCK_DGRAM:
1076 1077 1078 1079
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1080 1081
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1082
		default:
L
Linus Torvalds 已提交
1083 1084 1085 1086 1087 1088 1089 1090 1091
			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;
1092
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105
			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;
1106 1107
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1108 1109 1110 1111 1112 1113 1114
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1115 1116
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1117 1118 1119 1120 1121 1122
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1123
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1124 1125 1126
				u16 tclass,
				u32 *sid)
{
1127 1128
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1129

1130
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1131 1132 1133
	if (!buffer)
		return -ENOMEM;

1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145
	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
1146 1147 1148 1149 1150
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1151
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173
				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;

1174
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1175
	if (isec->initialized)
1176
		goto out_unlock;
L
Linus Torvalds 已提交
1177 1178

	sbsec = inode->i_sb->s_security;
1179
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1180 1181 1182 1183 1184 1185 1186
		/* 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);
1187
		goto out_unlock;
L
Linus Torvalds 已提交
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206
	}

	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) {
1207 1208 1209 1210 1211 1212 1213 1214 1215
			/*
			 * 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.
			 */
1216
			goto out_unlock;
L
Linus Torvalds 已提交
1217 1218 1219
		}

		len = INITCONTEXTLEN;
1220
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1221 1222 1223
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1224
			goto out_unlock;
L
Linus Torvalds 已提交
1225
		}
1226
		context[len] = '\0';
L
Linus Torvalds 已提交
1227 1228 1229
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1230 1231
			kfree(context);

L
Linus Torvalds 已提交
1232 1233 1234 1235 1236
			/* 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);
1237
				goto out_unlock;
L
Linus Torvalds 已提交
1238 1239
			}
			len = rc;
1240
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1241 1242 1243
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1244
				goto out_unlock;
L
Linus Torvalds 已提交
1245
			}
1246
			context[len] = '\0';
L
Linus Torvalds 已提交
1247 1248 1249 1250 1251 1252 1253
			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
1254
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1255
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1256 1257
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1258
				goto out_unlock;
L
Linus Torvalds 已提交
1259 1260 1261 1262 1263
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1264
			rc = security_context_to_sid_default(context, rc, &sid,
1265 1266
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1267
			if (rc) {
1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280
				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
1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298
				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);
1299 1300
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
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1301
		if (rc)
1302
			goto out_unlock;
L
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1303 1304
		isec->sid = sid;
		break;
1305 1306 1307
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1308
	default:
1309
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1310 1311
		isec->sid = sbsec->sid;

1312
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1313
			if (opt_dentry) {
L
Linus Torvalds 已提交
1314
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1315
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1316 1317 1318
							  isec->sclass,
							  &sid);
				if (rc)
1319
					goto out_unlock;
L
Linus Torvalds 已提交
1320 1321 1322 1323 1324 1325 1326 1327
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1328 1329
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362
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
1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375
/*
 * 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);
}

1376
/*
1377
 * Check permission between a pair of tasks, e.g. signal checks,
1378 1379
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1380
 * - this uses the default subjective creds of tsk1
1381 1382 1383
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1384 1385
			 u32 perms)
{
1386 1387
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1388

1389 1390 1391 1392 1393
	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
1394 1395
}

1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411
/*
 * 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);
}

1412 1413 1414 1415
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1416
/* Check whether a task is allowed to use a capability. */
1417
static int cred_has_capability(const struct cred *cred,
1418
			       int cap, int audit)
L
Linus Torvalds 已提交
1419
{
1420
	struct common_audit_data ad;
1421
	struct av_decision avd;
1422
	u16 sclass;
1423
	u32 sid = cred_sid(cred);
1424
	u32 av = CAP_TO_MASK(cap);
1425
	int rc;
L
Linus Torvalds 已提交
1426

1427
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
1428
	ad.tsk = current;
L
Linus Torvalds 已提交
1429 1430
	ad.u.cap = cap;

1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441
	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();
1442
		return -EINVAL;
1443
	}
1444

1445
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1446 1447 1448 1449 1450
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1451
	return rc;
L
Linus Torvalds 已提交
1452 1453 1454 1455 1456 1457
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1458
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1459

1460
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1461 1462 1463 1464 1465 1466
			    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). */
1467
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1468 1469
			  struct inode *inode,
			  u32 perms,
1470 1471
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1472 1473
{
	struct inode_security_struct *isec;
1474
	u32 sid;
L
Linus Torvalds 已提交
1475

1476 1477
	validate_creds(cred);

1478
	if (unlikely(IS_PRIVATE(inode)))
1479 1480
		return 0;

1481
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1482 1483
	isec = inode->i_security;

1484
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1485 1486
}

1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498
static int inode_has_perm_noadp(const struct cred *cred,
				struct inode *inode,
				u32 perms,
				unsigned flags)
{
	struct common_audit_data ad;

	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
	return inode_has_perm(cred, inode, perms, &ad, flags);
}

L
Linus Torvalds 已提交
1499 1500 1501
/* 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. */
1502
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1503 1504 1505 1506
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1507
	struct common_audit_data ad;
1508

E
Eric Paris 已提交
1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	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;

1524
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
E
Eric Paris 已提交
1525
	ad.u.path = *path;
1526
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1527 1528 1529 1530 1531 1532 1533 1534 1535 1536
}

/* 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. */
1537 1538 1539
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1540 1541
{
	struct file_security_struct *fsec = file->f_security;
1542
	struct inode *inode = file->f_path.dentry->d_inode;
1543
	struct common_audit_data ad;
1544
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1545 1546
	int rc;

1547 1548
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1549

1550 1551
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1552 1553 1554 1555
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1556
			goto out;
L
Linus Torvalds 已提交
1557 1558 1559
	}

	/* av is zero if only checking access to the descriptor. */
1560
	rc = 0;
L
Linus Torvalds 已提交
1561
	if (av)
1562
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1563

1564 1565
out:
	return rc;
L
Linus Torvalds 已提交
1566 1567 1568 1569 1570 1571 1572
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1573
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1574 1575
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1576
	u32 sid, newsid;
1577
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1578 1579 1580 1581 1582
	int rc;

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

1583 1584 1585
	sid = tsec->sid;
	newsid = tsec->create_sid;

1586 1587
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1588

1589
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1590 1591 1592 1593 1594
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1595
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1596 1597
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1598 1599 1600 1601
		if (rc)
			return rc;
	}

1602
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1603 1604 1605 1606 1607 1608 1609 1610
	if (rc)
		return rc;

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

1611 1612 1613 1614
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1615
	u32 sid = task_sid(ctx);
1616

1617
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1618 1619
}

1620 1621 1622
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628 1629 1630

/* 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;
1631
	struct common_audit_data ad;
1632
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1633 1634 1635 1636 1637 1638
	u32 av;
	int rc;

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

1639 1640
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1641 1642 1643

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1644
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658
	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
1659 1660
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1661 1662 1663
		return 0;
	}

1664
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1665 1666 1667 1668 1669 1670 1671 1672 1673
	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;
1674
	struct common_audit_data ad;
1675
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1676 1677 1678 1679 1680 1681 1682 1683 1684
	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;

1685
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
L
Linus Torvalds 已提交
1686

1687
	ad.u.dentry = old_dentry;
1688
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1689 1690 1691
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1692
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1693 1694 1695 1696
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1697
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1698 1699 1700 1701 1702
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1703
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1704 1705 1706
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1707
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1708 1709 1710 1711 1712
	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);
1713
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723
				  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. */
1724
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1725 1726
			       struct super_block *sb,
			       u32 perms,
1727
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1728 1729
{
	struct superblock_security_struct *sbsec;
1730
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1731 1732

	sbsec = sb->s_security;
1733
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
}

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

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

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

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

	return av;
}

1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786
/* 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
1787
/*
1788
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1789 1790
 * open permission.
 */
1791
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1792
{
1793
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1794

1795 1796 1797
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1798 1799 1800
	return av;
}

L
Linus Torvalds 已提交
1801 1802
/* Hook functions begin here. */

1803
static int selinux_ptrace_access_check(struct task_struct *child,
1804
				     unsigned int mode)
L
Linus Torvalds 已提交
1805 1806 1807
{
	int rc;

1808
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1809 1810 1811
	if (rc)
		return rc;

1812
	if (mode == PTRACE_MODE_READ) {
1813 1814 1815
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1816 1817
	}

1818
	return current_has_perm(child, PROCESS__PTRACE);
1819 1820 1821 1822 1823 1824
}

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

1825
	rc = cap_ptrace_traceme(parent);
1826 1827 1828 1829
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1830 1831 1832
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1833
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1834 1835 1836
{
	int error;

1837
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1838 1839 1840
	if (error)
		return error;

1841
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1842 1843
}

D
David Howells 已提交
1844 1845 1846 1847
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
1848 1849 1850
{
	int error;

1851
	error = cap_capset(new, old,
D
David Howells 已提交
1852
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1853 1854 1855
	if (error)
		return error;

D
David Howells 已提交
1856
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1857 1858
}

1859 1860 1861 1862 1863 1864 1865 1866 1867 1868
/*
 * (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.
 */

1869 1870
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1871 1872 1873
{
	int rc;

1874
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1875 1876 1877
	if (rc)
		return rc;

1878
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1879 1880 1881 1882
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1883
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1884 1885 1886 1887 1888 1889
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1890 1891 1892 1893 1894
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1895
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1896 1897 1898 1899
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1900
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1901 1902 1903 1904
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1905 1906 1907 1908 1909 1910
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1911 1912
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1913
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1914 1915
}

1916
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1917 1918 1919 1920
{
	int rc;

	switch (type) {
1921 1922
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1923 1924
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1925 1926 1927 1928
	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:
1929 1930
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1931 1932 1933 1934 1935
	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 */
1936 1937 1938
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950
	}
	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.
 */
1951
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1952 1953 1954
{
	int rc, cap_sys_admin = 0;

1955
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1956
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1957 1958 1959
	if (rc == 0)
		cap_sys_admin = 1;

1960
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1961 1962 1963 1964
}

/* binprm security operations */

1965
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1966
{
1967 1968
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1969
	struct inode_security_struct *isec;
1970
	struct common_audit_data ad;
1971
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1972 1973
	int rc;

1974
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1975 1976 1977
	if (rc)
		return rc;

1978 1979 1980
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
1981 1982
		return 0;

1983 1984
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
1985 1986 1987
	isec = inode->i_security;

	/* Default to the current task SID. */
1988 1989
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
1990

1991
	/* Reset fs, key, and sock SIDs on execve. */
1992 1993 1994
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
1995

1996 1997
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
1998
		/* Reset exec SID on execve. */
1999
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2000 2001
	} else {
		/* Check for a default transition on this program. */
2002
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2003 2004
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2005 2006 2007 2008
		if (rc)
			return rc;
	}

2009 2010
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2011

J
Josef Sipek 已提交
2012
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2013
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2014

2015 2016
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2017 2018 2019 2020 2021
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2022
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2023 2024 2025 2026
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2027
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2028 2029 2030 2031
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049
		/* 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();
2050
			tracer = ptrace_parent(current);
2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064
			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
2065

2066 2067
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2068 2069 2070 2071 2072
	}

	return 0;
}

2073
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2074
{
2075
	const struct task_security_struct *tsec = current_security();
2076
	u32 sid, osid;
L
Linus Torvalds 已提交
2077 2078
	int atsecure = 0;

2079 2080 2081 2082
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2083 2084 2085
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2086
		atsecure = avc_has_perm(osid, sid,
2087 2088
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2089 2090
	}

2091
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2092 2093 2094
}

/* Derived from fs/exec.c:flush_old_files. */
2095 2096
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2097
{
2098
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2099
	struct file *file, *devnull = NULL;
2100
	struct tty_struct *tty;
2101
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2102
	long j = -1;
2103
	int drop_tty = 0;
L
Linus Torvalds 已提交
2104

2105
	tty = get_current_tty();
L
Linus Torvalds 已提交
2106
	if (tty) {
N
Nick Piggin 已提交
2107
		spin_lock(&tty_files_lock);
2108
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2109
			struct tty_file_private *file_priv;
2110 2111
			struct inode *inode;

L
Linus Torvalds 已提交
2112 2113 2114 2115 2116
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
N
Nick Piggin 已提交
2117 2118 2119
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2120
			inode = file->f_path.dentry->d_inode;
2121 2122
			if (inode_has_perm_noadp(cred, inode,
					   FILE__READ | FILE__WRITE, 0)) {
2123
				drop_tty = 1;
L
Linus Torvalds 已提交
2124 2125
			}
		}
N
Nick Piggin 已提交
2126
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2127
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2128
	}
2129 2130 2131
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2132 2133 2134

	/* Revalidate access to inherited open files. */

2135
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
L
Linus Torvalds 已提交
2136 2137 2138 2139 2140 2141 2142 2143

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

		j++;
		i = j * __NFDBITS;
2144
		fdt = files_fdtable(files);
2145
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2146
			break;
2147
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2148 2149 2150
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2151
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2152 2153 2154 2155
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2156
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2168
						get_file(devnull);
L
Linus Torvalds 已提交
2169
					} else {
2170 2171 2172 2173
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2174 2175
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2192 2193 2194 2195
/*
 * 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
2196
{
2197 2198 2199
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2200

2201 2202 2203
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2204

2205 2206
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2207

2208 2209
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2210

2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223
	/* 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) {
2224 2225
		/* protect against do_prlimit() */
		task_lock(current);
2226 2227 2228 2229
		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
2230
		}
2231 2232
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2233 2234 2235 2236
	}
}

/*
2237 2238
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2239
 */
2240
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2241
{
2242
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2243
	struct itimerval itimer;
2244
	u32 osid, sid;
L
Linus Torvalds 已提交
2245 2246
	int rc, i;

2247 2248 2249 2250
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2251 2252
		return;

2253 2254 2255 2256 2257 2258 2259 2260
	/* 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
2261 2262 2263 2264 2265
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2266 2267 2268 2269 2270
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2271 2272 2273
		spin_unlock_irq(&current->sighand->siglock);
	}

2274 2275
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2276
	read_lock(&tasklist_lock);
2277
	__wake_up_parent(current, current->real_parent);
2278
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302
}

/* 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)
{
2303 2304 2305
	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) ||
2306 2307
		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
2308 2309 2310 2311 2312 2313 2314
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2315
	} else
L
Linus Torvalds 已提交
2316 2317 2318 2319 2320
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2321 2322
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2323 2324 2325 2326 2327 2328
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2329
	} else
2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341
		*first = 0;

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

2342
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2343 2344 2345 2346
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2347
	int open_quote = 0;
L
Linus Torvalds 已提交
2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362

	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 {
2363 2364 2365 2366
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2367 2368 2369
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2370
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2371 2372 2373 2374 2375 2376 2377
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2378
	strcpy(in_save, nosec_save);
2379
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2380 2381 2382 2383
out:
	return rc;
}

2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

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

	if (!data)
		return 0;

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

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

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

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

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

		if (flags[i] == SE_SBLABELSUPP)
			continue;
		len = strlen(mount_options[i]);
		rc = security_context_to_sid(mount_options[i], len, &sid);
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
			goto out_free_opts;
		}
		rc = -EINVAL;
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
				goto out_bad_option;
			break;
		case CONTEXT_MNT:
			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
				goto out_bad_option;
			break;
		case ROOTCONTEXT_MNT: {
			struct inode_security_struct *root_isec;
			root_isec = sb->s_root->d_inode->i_security;

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

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

2469
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2470
{
2471
	const struct cred *cred = current_cred();
2472
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2473 2474 2475 2476 2477 2478
	int rc;

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

2479 2480 2481 2482
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2483 2484
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = sb->s_root;
2485
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2486 2487
}

2488
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2489
{
2490
	const struct cred *cred = current_cred();
2491
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2492

2493 2494
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry->d_sb->s_root;
2495
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2496 2497
}

2498
static int selinux_mount(char *dev_name,
2499
			 struct path *path,
2500 2501 2502
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2503
{
2504
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2505 2506

	if (flags & MS_REMOUNT)
2507
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2508
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2509
	else
E
Eric Paris 已提交
2510
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2511 2512 2513 2514
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2515
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2516

2517
	return superblock_has_perm(cred, mnt->mnt_sb,
2518
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532
}

/* 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);
}

2533
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2534 2535
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2536
{
2537
	const struct task_security_struct *tsec = current_security();
2538 2539
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2540
	u32 sid, newsid, clen;
2541
	int rc;
2542
	char *namep = NULL, *context;
2543 2544 2545 2546

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

2547 2548 2549
	sid = tsec->sid;
	newsid = tsec->create_sid;

2550 2551 2552 2553
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2554
		rc = security_transition_sid(sid, dsec->sid,
2555
					     inode_mode_to_security_class(inode->i_mode),
2556
					     qstr, &newsid);
2557 2558 2559 2560
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2561
			       __func__,
2562 2563 2564 2565 2566
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2567
	/* Possibly defer initialization to selinux_complete_init. */
2568
	if (sbsec->flags & SE_SBINITIALIZED) {
2569 2570 2571 2572 2573
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2574

2575
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2576 2577
		return -EOPNOTSUPP;

2578
	if (name) {
2579
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2580 2581 2582 2583
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2584

2585
	if (value && len) {
2586
		rc = security_sid_to_context_force(newsid, &context, &clen);
2587 2588 2589 2590 2591 2592
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2593 2594 2595 2596 2597
	}

	return 0;
}

L
Linus Torvalds 已提交
2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

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

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

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

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

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

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

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2634
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2635 2636 2637 2638 2639 2640
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2641 2642
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2643
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2644 2645 2646 2647
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2648
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2649

E
Eric Paris 已提交
2650
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2651 2652
}

2653
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2654
{
2655
	const struct cred *cred = current_cred();
2656 2657 2658
	struct common_audit_data ad;
	u32 perms;
	bool from_access;
2659
	unsigned flags = mask & MAY_NOT_BLOCK;
L
Linus Torvalds 已提交
2660

2661
	from_access = mask & MAY_ACCESS;
2662 2663
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2664 2665
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2666 2667
		return 0;

2668 2669
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
2670 2671 2672 2673 2674 2675

	if (from_access)
		ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;

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

2676
	return inode_has_perm(cred, inode, perms, &ad, flags);
L
Linus Torvalds 已提交
2677 2678 2679 2680
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2681
	const struct cred *cred = current_cred();
2682
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2683

2684 2685 2686 2687 2688 2689 2690
	/* 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
2691

2692 2693
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2694
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2695

E
Eric Paris 已提交
2696
	return dentry_has_perm(cred, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2697 2698 2699 2700
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2701
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2702 2703 2704 2705
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2706

E
Eric Paris 已提交
2707
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2708 2709
}

2710
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2711
{
2712 2713
	const struct cred *cred = current_cred();

2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727
	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
2728
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2729 2730
}

2731 2732
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
2733 2734 2735 2736
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2737
	struct common_audit_data ad;
2738
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2739 2740
	int rc = 0;

2741 2742
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2743 2744

	sbsec = inode->i_sb->s_security;
2745
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2746 2747
		return -EOPNOTSUPP;

2748
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2749 2750
		return -EPERM;

2751 2752
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2753

2754
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2755 2756 2757 2758 2759
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2760 2761 2762 2763 2764
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2765 2766 2767
	if (rc)
		return rc;

2768
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2769 2770 2771 2772
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2773
	rc = security_validate_transition(isec->sid, newsid, sid,
2774
					  isec->sclass);
L
Linus Torvalds 已提交
2775 2776 2777 2778 2779 2780 2781 2782 2783 2784
	if (rc)
		return rc;

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

2785
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2786
					const void *value, size_t size,
2787
					int flags)
L
Linus Torvalds 已提交
2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798
{
	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;
	}

2799
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2800
	if (rc) {
2801 2802 2803
		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
2804 2805 2806 2807 2808 2809 2810
		return;
	}

	isec->sid = newsid;
	return;
}

2811
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2812
{
2813 2814
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2815
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2816 2817
}

2818
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2819
{
2820 2821
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2822
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2823 2824
}

2825
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2826
{
2827 2828
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2829 2830 2831 2832 2833 2834

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

2835
/*
2836
 * Copy the inode security context value to the user.
2837 2838 2839
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2840
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2841
{
2842 2843 2844
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2845
	struct inode_security_struct *isec = inode->i_security;
2846

2847 2848
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2849

2850 2851 2852 2853 2854 2855 2856 2857 2858
	/*
	 * 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.
	 */
2859
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2860
				SECURITY_CAP_NOAUDIT);
2861 2862 2863 2864 2865
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2866 2867 2868 2869 2870 2871 2872 2873 2874 2875
	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
2876 2877 2878
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2879
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890
{
	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;

2891
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2892 2893 2894 2895
	if (rc)
		return rc;

	isec->sid = newsid;
2896
	isec->initialized = 1;
L
Linus Torvalds 已提交
2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907
	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;
}

2908 2909 2910 2911 2912 2913
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
2914 2915
/* file security operations */

2916
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2917
{
2918
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2919
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2920 2921 2922 2923 2924

	/* 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;

2925 2926
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2927 2928
}

2929 2930
static int selinux_file_permission(struct file *file, int mask)
{
2931 2932 2933 2934 2935
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2936
	if (!mask)
2937 2938 2939
		/* No permission to check.  Existence test. */
		return 0;

2940 2941 2942 2943 2944
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2945 2946 2947
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960
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)
{
2961
	const struct cred *cred = current_cred();
2962
	int error = 0;
L
Linus Torvalds 已提交
2963

2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
	case EXT2_IOC_GETFLAGS:
	/* fall through */
	case EXT2_IOC_GETVERSION:
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
2976

2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988
	case EXT2_IOC_SETFLAGS:
	/* fall through */
	case EXT2_IOC_SETVERSION:
		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
2989

2990 2991
	case KDSKBENT:
	case KDSKBSENT:
2992 2993
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
2994 2995 2996 2997 2998 2999 3000 3001 3002
		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
3003 3004
}

3005 3006
static int default_noexec;

L
Linus Torvalds 已提交
3007 3008
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3009
	const struct cred *cred = current_cred();
D
David Howells 已提交
3010
	int rc = 0;
3011

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

	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;

3035
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3036
	}
D
David Howells 已提交
3037 3038 3039

error:
	return rc;
L
Linus Torvalds 已提交
3040 3041 3042
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3043 3044
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3045
{
3046
	int rc = 0;
3047
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3048

3049 3050 3051 3052 3053 3054
	/*
	 * 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.
	 */
3055
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3056 3057
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3058 3059 3060 3061 3062 3063
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3064
	if (rc || addr_only)
L
Linus Torvalds 已提交
3065 3066 3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

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

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3078
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3079 3080 3081 3082

	if (selinux_checkreqprot)
		prot = reqprot;

3083 3084
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3085
		int rc = 0;
3086 3087
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3088
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3089 3090 3091
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3092
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3093 3094 3095 3096 3097 3098 3099 3100
		} 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
3101
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3102
		}
3103 3104 3105
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3106 3107 3108 3109 3110 3111

	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)
{
3112 3113 3114
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3115 3116 3117 3118 3119
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3120
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3121 3122 3123
	int err = 0;

	switch (cmd) {
3124 3125 3126 3127 3128
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3129

3130
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3131
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3132
			break;
3133 3134 3135 3136 3137 3138 3139 3140
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3141
		err = file_has_perm(cred, file, 0);
3142 3143 3144 3145
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3146
#if BITS_PER_LONG == 32
3147 3148 3149
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3150
#endif
3151 3152
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3153
			break;
3154
		}
3155
		err = file_has_perm(cred, file, FILE__LOCK);
3156
		break;
L
Linus Torvalds 已提交
3157 3158 3159 3160 3161 3162 3163 3164 3165 3166
	}

	return err;
}

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

	fsec = file->f_security;
3167
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3168 3169 3170 3171 3172 3173 3174

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3175
	struct file *file;
3176
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3177 3178 3179 3180
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3181
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3182 3183 3184 3185 3186 3187 3188 3189

	fsec = file->f_security;

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

3190
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3191 3192 3193 3194 3195
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3196 3197 3198
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3199 3200
}

3201
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3202 3203 3204 3205
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3206

3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3227
	return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3228 3229
}

L
Linus Torvalds 已提交
3230 3231 3232 3233
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3234
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3235 3236
}

3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251
/*
 * 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
3252 3253 3254 3255
/*
 * 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
3256
{
D
David Howells 已提交
3257
	struct task_security_struct *tsec = cred->security;
3258

3259 3260 3261 3262 3263
	/*
	 * 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);
3264
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3265 3266
	kfree(tsec);
}
L
Linus Torvalds 已提交
3267

D
David Howells 已提交
3268 3269 3270 3271 3272 3273 3274 3275
/*
 * 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
3276

D
David Howells 已提交
3277
	old_tsec = old->security;
L
Linus Torvalds 已提交
3278

D
David Howells 已提交
3279 3280 3281
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3282

D
David Howells 已提交
3283
	new->security = tsec;
L
Linus Torvalds 已提交
3284 3285 3286
	return 0;
}

3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297
/*
 * 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;
}

3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338
/*
 * 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;
3339
	return ret;
3340 3341
}

3342
static int selinux_kernel_module_request(char *kmod_name)
3343
{
3344 3345 3346 3347 3348 3349 3350 3351 3352 3353
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

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

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3354 3355
}

L
Linus Torvalds 已提交
3356 3357
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3358
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3359 3360 3361 3362
}

static int selinux_task_getpgid(struct task_struct *p)
{
3363
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3364 3365 3366 3367
}

static int selinux_task_getsid(struct task_struct *p)
{
3368
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3369 3370
}

3371 3372
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3373
	*secid = task_sid(p);
3374 3375
}

L
Linus Torvalds 已提交
3376 3377 3378 3379
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3380
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3381 3382 3383
	if (rc)
		return rc;

3384
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3385 3386
}

3387 3388
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3389 3390
	int rc;

3391
	rc = cap_task_setioprio(p, ioprio);
3392 3393 3394
	if (rc)
		return rc;

3395
	return current_has_perm(p, PROCESS__SETSCHED);
3396 3397
}

3398 3399
static int selinux_task_getioprio(struct task_struct *p)
{
3400
	return current_has_perm(p, PROCESS__GETSCHED);
3401 3402
}

3403 3404
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3405
{
3406
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3407 3408 3409 3410

	/* 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
3411
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3412
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3413
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3414 3415 3416 3417

	return 0;
}

3418
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3419
{
3420 3421
	int rc;

3422
	rc = cap_task_setscheduler(p);
3423 3424 3425
	if (rc)
		return rc;

3426
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3427 3428 3429 3430
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3431
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3432 3433
}

3434 3435
static int selinux_task_movememory(struct task_struct *p)
{
3436
	return current_has_perm(p, PROCESS__SETSCHED);
3437 3438
}

3439 3440
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3441 3442 3443 3444 3445 3446 3447 3448
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3449
	if (secid)
3450 3451
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3452
	else
3453
		rc = current_has_perm(p, perm);
3454
	return rc;
L
Linus Torvalds 已提交
3455 3456 3457 3458
}

static int selinux_task_wait(struct task_struct *p)
{
3459
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3460 3461 3462 3463 3464 3465
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3466
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3467

3468
	isec->sid = sid;
L
Linus Torvalds 已提交
3469 3470 3471 3472
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3473
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3474
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3475 3476 3477 3478
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3479
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

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

3492 3493 3494
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3495
	switch (ih->protocol) {
3496 3497
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3498

3499 3500
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3501 3502 3503 3504 3505 3506 3507 3508 3509

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

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3510 3511 3512 3513 3514 3515 3516 3517
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3518
		offset += ihlen;
3519
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3520
		if (uh == NULL)
3521
			break;
L
Linus Torvalds 已提交
3522

3523 3524 3525 3526
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3527

J
James Morris 已提交
3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3542
	}
J
James Morris 已提交
3543

3544 3545 3546
	default:
		break;
	}
L
Linus Torvalds 已提交
3547 3548 3549 3550 3551 3552 3553
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3554
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3555
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3556 3557 3558 3559 3560
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3561
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3562 3563 3564 3565 3566 3567 3568 3569 3570 3571
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

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

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3572
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3573 3574 3575
	if (offset < 0)
		goto out;

3576 3577 3578
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3579 3580
	switch (nexthdr) {
	case IPPROTO_TCP: {
3581
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603

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

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

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

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

J
James Morris 已提交
3604 3605 3606 3607 3608 3609 3610 3611 3612 3613
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3614
	}
J
James Morris 已提交
3615

L
Linus Torvalds 已提交
3616 3617 3618 3619 3620 3621 3622 3623 3624 3625
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3626
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3627
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3628
{
3629 3630
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3631 3632 3633

	switch (ad->u.net.family) {
	case PF_INET:
3634
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3635 3636 3637 3638 3639
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3640 3641 3642

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3643
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3644 3645 3646 3647 3648
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3649 3650
#endif	/* IPV6 */
	default:
3651 3652
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3653 3654
	}

3655 3656 3657 3658
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3659
	return ret;
3660 3661 3662 3663 3664

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3665 3666
}

3667
/**
3668
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3669
 * @skb: the packet
3670
 * @family: protocol family
3671
 * @sid: the packet's peer label SID
3672 3673
 *
 * Description:
3674 3675 3676 3677 3678 3679
 * 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.
3680 3681
 *
 */
3682
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3683
{
3684
	int err;
3685 3686
	u32 xfrm_sid;
	u32 nlbl_sid;
3687
	u32 nlbl_type;
3688 3689

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3690
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3691

3692 3693 3694 3695 3696
	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");
3697
		return -EACCES;
3698
	}
3699 3700

	return 0;
3701 3702
}

L
Linus Torvalds 已提交
3703
/* socket security operations */
3704

3705 3706
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3707
{
3708 3709 3710 3711 3712 3713 3714
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3715 3716
}

3717
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3718
{
3719
	struct sk_security_struct *sksec = sk->sk_security;
3720
	struct common_audit_data ad;
3721
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3722

3723 3724
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3725

3726
	COMMON_AUDIT_DATA_INIT(&ad, NET);
3727
	ad.u.net.sk = sk;
L
Linus Torvalds 已提交
3728

3729
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3730 3731 3732 3733 3734
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3735
	const struct task_security_struct *tsec = current_security();
3736
	u32 newsid;
3737
	u16 secclass;
3738
	int rc;
L
Linus Torvalds 已提交
3739 3740

	if (kern)
3741
		return 0;
3742 3743

	secclass = socket_type_to_security_class(family, type, protocol);
3744 3745 3746 3747
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3748
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3749 3750
}

V
Venkat Yekkirala 已提交
3751 3752
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3753
{
3754
	const struct task_security_struct *tsec = current_security();
3755
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3756
	struct sk_security_struct *sksec;
3757 3758
	int err = 0;

3759 3760
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3761 3762
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3763 3764 3765 3766 3767
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3768

L
Linus Torvalds 已提交
3769 3770
	isec->initialized = 1;

3771 3772 3773
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3774
		sksec->sclass = isec->sclass;
3775
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3776 3777
	}

V
Venkat Yekkirala 已提交
3778
	return err;
L
Linus Torvalds 已提交
3779 3780 3781 3782 3783 3784 3785 3786
}

/* 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)
{
3787
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3788 3789 3790
	u16 family;
	int err;

3791
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3792 3793 3794 3795 3796
	if (err)
		goto out;

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

		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;
		}

3820 3821 3822 3823 3824 3825
		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
3826 3827
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3828 3829
				if (err)
					goto out;
3830
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3831 3832
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
3833 3834
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3835 3836 3837 3838
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3839
		}
3840

3841
		switch (sksec->sclass) {
3842
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3843 3844
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3845

3846
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3847 3848
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3849 3850 3851 3852 3853

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3854 3855 3856 3857
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3858

3859
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3860 3861
		if (err)
			goto out;
3862

3863
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3864 3865 3866 3867 3868 3869 3870 3871
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

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

3872 3873
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3874 3875 3876 3877 3878 3879 3880 3881 3882
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3883
	struct sock *sk = sock->sk;
3884
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3885 3886
	int err;

3887
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3888 3889 3890 3891
	if (err)
		return err;

	/*
J
James Morris 已提交
3892
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3893
	 */
3894 3895
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3896
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3897 3898 3899
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3900
		u32 sid, perm;
L
Linus Torvalds 已提交
3901 3902 3903

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3904
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3905 3906 3907 3908
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3909
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3910 3911 3912 3913
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3914
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3915 3916 3917
		if (err)
			goto out;

3918
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3919 3920
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3921
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3922 3923
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
3924
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3925 3926 3927 3928
		if (err)
			goto out;
	}

3929 3930
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3931 3932 3933 3934 3935 3936
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3937
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3938 3939 3940 3941 3942 3943 3944 3945
}

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

3946
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960
	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,
3961
				  int size)
L
Linus Torvalds 已提交
3962
{
3963
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
3964 3965 3966 3967 3968
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
3969
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
3970 3971 3972 3973
}

static int selinux_socket_getsockname(struct socket *sock)
{
3974
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3975 3976 3977 3978
}

static int selinux_socket_getpeername(struct socket *sock)
{
3979
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3980 3981
}

3982
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3983
{
3984 3985
	int err;

3986
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3987 3988 3989 3990
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
3991 3992 3993 3994 3995
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
3996
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
3997 3998 3999 4000
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4001
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4002 4003
}

4004 4005
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4006 4007
					      struct sock *newsk)
{
4008 4009
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4010
	struct sk_security_struct *sksec_new = newsk->sk_security;
4011
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4012 4013
	int err;

4014
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4015
	ad.u.net.sk = other;
L
Linus Torvalds 已提交
4016

4017 4018
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4019 4020 4021 4022 4023
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4024 4025 4026 4027 4028
	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;
4029

4030 4031 4032 4033
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4034 4035 4036 4037 4038
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4039 4040
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4041
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4042

4043
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4044 4045
	ad.u.net.sk = other->sk;

4046 4047
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4048 4049
}

4050 4051
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4052
				    struct common_audit_data *ad)
4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072
{
	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);
}

4073
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4074
				       u16 family)
4075
{
4076
	int err = 0;
4077 4078
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4079
	struct common_audit_data ad;
4080 4081
	char *addrp;

4082
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4083
	ad.u.net.netif = skb->skb_iif;
4084 4085 4086 4087
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4088

4089
	if (selinux_secmark_enabled()) {
4090
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4091
				   PACKET__RECV, &ad);
4092 4093 4094
		if (err)
			return err;
	}
4095

4096 4097 4098 4099
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4100

4101 4102 4103 4104 4105
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4106
	int err;
4107
	struct sk_security_struct *sksec = sk->sk_security;
4108 4109
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4110
	struct common_audit_data ad;
4111
	char *addrp;
4112 4113
	u8 secmark_active;
	u8 peerlbl_active;
4114 4115

	if (family != PF_INET && family != PF_INET6)
4116
		return 0;
4117 4118

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4119
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4120 4121
		family = PF_INET;

4122 4123 4124 4125
	/* 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. */
4126
	if (!selinux_policycap_netpeer)
4127 4128 4129 4130 4131 4132 4133
		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;

4134
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4135
	ad.u.net.netif = skb->skb_iif;
4136
	ad.u.net.family = family;
4137
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4138
	if (err)
4139
		return err;
4140

4141
	if (peerlbl_active) {
4142 4143 4144
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4145 4146
		if (err)
			return err;
4147
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4148
					       peer_sid, &ad);
4149 4150
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4151
			return err;
4152
		}
4153 4154
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4155 4156
		if (err)
			selinux_netlbl_err(skb, err, 0);
4157 4158
	}

4159
	if (secmark_active) {
4160 4161 4162 4163 4164 4165
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4166
	return err;
L
Linus Torvalds 已提交
4167 4168
}

C
Catherine Zhang 已提交
4169 4170
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4171 4172 4173 4174
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4175
	struct sk_security_struct *sksec = sock->sk->sk_security;
4176
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4177

4178 4179
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4180
		peer_sid = sksec->peer_sid;
4181 4182
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4183

C
Catherine Zhang 已提交
4184
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4185
	if (err)
4186
		return err;
L
Linus Torvalds 已提交
4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202

	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;
}

4203
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4204
{
4205
	u32 peer_secid = SECSID_NULL;
4206
	u16 family;
C
Catherine Zhang 已提交
4207

4208 4209 4210 4211 4212
	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)
4213 4214 4215 4216 4217
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4218
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4219
	else if (skb)
4220
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4221

4222
out:
4223
	*secid = peer_secid;
4224 4225 4226
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4227 4228
}

A
Al Viro 已提交
4229
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4230
{
4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242
	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
4243 4244 4245 4246
}

static void selinux_sk_free_security(struct sock *sk)
{
4247 4248 4249 4250 4251
	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
4252 4253
}

4254
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4255
{
4256 4257
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4258

4259 4260 4261
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4262

4263
	selinux_netlbl_sk_security_reset(newsksec);
4264 4265
}

V
Venkat Yekkirala 已提交
4266
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4267
{
4268
	if (!sk)
V
Venkat Yekkirala 已提交
4269
		*secid = SECINITSID_ANY_SOCKET;
4270 4271
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4272

V
Venkat Yekkirala 已提交
4273
		*secid = sksec->sid;
4274
	}
4275 4276
}

4277
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4278 4279 4280 4281
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4282 4283 4284
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4285
	sksec->sclass = isec->sclass;
4286 4287
}

4288 4289
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4290 4291 4292
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4293
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4294
	u32 newsid;
4295 4296
	u32 peersid;

4297 4298 4299 4300 4301
	/* 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);
4302 4303
	if (err)
		return err;
4304 4305
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4306
		req->peer_secid = SECSID_NULL;
4307 4308 4309 4310 4311 4312
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4313 4314
	}

4315
	return selinux_netlbl_inet_conn_request(req, family);
4316 4317
}

4318 4319
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4320 4321 4322 4323
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4324
	newsksec->peer_sid = req->peer_secid;
4325 4326 4327 4328
	/* 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. */
4329

P
Paul Moore 已提交
4330 4331
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4332
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4333 4334
}

4335
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4336
{
4337
	u16 family = sk->sk_family;
4338 4339
	struct sk_security_struct *sksec = sk->sk_security;

4340 4341 4342 4343 4344
	/* 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);
4345 4346
}

4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367
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);
}

4368 4369
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4370
{
4371
	fl->flowi_secid = req->secid;
4372 4373
}

4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

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

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

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

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

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

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

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

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

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4427 4428 4429 4430 4431
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4432
	struct sk_security_struct *sksec = sk->sk_security;
4433

L
Linus Torvalds 已提交
4434 4435 4436 4437
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4438
	nlh = nlmsg_hdr(skb);
4439

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

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

4457
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4458 4459 4460 4461 4462 4463
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4464 4465
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4466
{
4467
	int err;
4468 4469
	char *addrp;
	u32 peer_sid;
4470
	struct common_audit_data ad;
4471
	u8 secmark_active;
4472
	u8 netlbl_active;
4473
	u8 peerlbl_active;
4474

4475 4476
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4477

4478
	secmark_active = selinux_secmark_enabled();
4479 4480
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4481 4482
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4483

4484 4485 4486
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4487
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4488 4489 4490 4491 4492
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4493 4494 4495 4496 4497
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4498
			return NF_DROP;
4499 4500
		}
	}
4501 4502 4503 4504 4505 4506

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

4507 4508 4509 4510 4511 4512 4513 4514
	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;

4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537
	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 */

4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568
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);
}

4569 4570
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4571
						u16 family)
4572 4573 4574
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4575
	struct common_audit_data ad;
4576 4577
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4578

4579 4580 4581 4582
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4583
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4584 4585 4586 4587 4588
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4589
	if (selinux_secmark_enabled())
4590
		if (avc_has_perm(sksec->sid, skb->secmark,
4591
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4592
			return NF_DROP_ERR(-ECONNREFUSED);
4593

4594 4595
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4596 4597

	return NF_ACCEPT;
4598 4599
}

4600 4601
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4602
{
4603 4604
	u32 secmark_perm;
	u32 peer_sid;
4605
	struct sock *sk;
4606
	struct common_audit_data ad;
4607 4608 4609
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4610

4611 4612 4613 4614
	/* 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. */
4615
	if (!selinux_policycap_netpeer)
4616
		return selinux_ip_postroute_compat(skb, ifindex, family);
4617
#ifdef CONFIG_XFRM
4618 4619 4620 4621 4622 4623
	/* 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
4624
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4625
		return NF_ACCEPT;
4626
#endif
4627 4628 4629 4630 4631
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4632 4633 4634 4635
	/* 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 */
4636
	sk = skb->sk;
4637
	if (sk == NULL) {
4638 4639
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4640
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4641
				return NF_DROP;
4642 4643
		} else {
			secmark_perm = PACKET__SEND;
4644
			peer_sid = SECINITSID_KERNEL;
4645
		}
4646
	} else {
4647 4648 4649 4650
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4651

4652
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4653 4654 4655
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4656
		return NF_DROP;
4657

4658 4659 4660
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4661
			return NF_DROP_ERR(-ECONNREFUSED);
4662 4663 4664 4665 4666 4667

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4668
			return NF_DROP;
4669 4670
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4671
			return NF_DROP_ERR(-ECONNREFUSED);
4672 4673

		if (sel_netnode_sid(addrp, family, &node_sid))
4674
			return NF_DROP;
4675 4676
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4677
			return NF_DROP_ERR(-ECONNREFUSED);
4678
	}
4679

4680
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4681 4682
}

4683 4684 4685 4686 4687
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
4688
{
4689
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4690 4691 4692
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4693 4694 4695 4696 4697
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
4698
{
4699
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4700 4701 4702 4703 4704 4705 4706 4707 4708
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4709
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4710 4711 4712
	if (err)
		return err;

4713
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4714 4715
}

4716
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4717
{
4718
	int err;
4719
	struct common_audit_data ad;
4720
	u32 sid;
4721

4722
	err = cap_netlink_recv(skb, capability);
4723 4724 4725
	if (err)
		return err;

4726
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4727 4728
	ad.u.cap = capability;

4729 4730 4731
	security_task_getsecid(current, &sid);
	return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
			    CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4732 4733 4734 4735 4736 4737 4738
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4739
	u32 sid;
L
Linus Torvalds 已提交
4740

J
James Morris 已提交
4741
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4742 4743 4744
	if (!isec)
		return -ENOMEM;

4745
	sid = task_sid(task);
L
Linus Torvalds 已提交
4746
	isec->sclass = sclass;
4747
	isec->sid = sid;
L
Linus Torvalds 已提交
4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763
	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
4764
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782
	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,
4783
			u32 perms)
L
Linus Torvalds 已提交
4784 4785
{
	struct ipc_security_struct *isec;
4786
	struct common_audit_data ad;
4787
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4788 4789 4790

	isec = ipc_perms->security;

4791
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4792 4793
	ad.u.ipc_id = ipc_perms->key;

4794
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810
}

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;
4811
	struct common_audit_data ad;
4812
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4813 4814 4815 4816 4817 4818 4819 4820
	int rc;

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

	isec = msq->q_perm.security;

4821
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4822
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4823

4824
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840
			  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;
4841
	struct common_audit_data ad;
4842
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4843 4844 4845

	isec = msq->q_perm.security;

4846
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4847 4848
	ad.u.ipc_id = msq->q_perm.key;

4849
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4850 4851 4852 4853 4854 4855 4856 4857
			    MSGQ__ASSOCIATE, &ad);
}

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

4858
	switch (cmd) {
L
Linus Torvalds 已提交
4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876
	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;
	}

4877
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4878 4879 4880 4881 4882 4883 4884
	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;
4885
	struct common_audit_data ad;
4886
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899
	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
		 */
4900
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4901
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4902 4903 4904 4905
		if (rc)
			return rc;
	}

4906
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4907 4908 4909
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4910
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4911 4912 4913
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4914 4915
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4916 4917
	if (!rc)
		/* Can the message be put in the queue? */
4918 4919
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4920 4921 4922 4923 4924 4925 4926 4927 4928 4929

	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;
4930
	struct common_audit_data ad;
4931
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4932 4933 4934 4935 4936
	int rc;

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

4937
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4938
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4939

4940
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4941 4942
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4943
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4944 4945 4946 4947 4948 4949 4950 4951
				  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;
4952
	struct common_audit_data ad;
4953
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4954 4955 4956 4957 4958 4959 4960 4961
	int rc;

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

	isec = shp->shm_perm.security;

4962
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4963
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4964

4965
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981
			  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;
4982
	struct common_audit_data ad;
4983
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4984 4985 4986

	isec = shp->shm_perm.security;

4987
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4988 4989
	ad.u.ipc_id = shp->shm_perm.key;

4990
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4991 4992 4993 4994 4995 4996 4997 4998 4999
			    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;

5000
	switch (cmd) {
L
Linus Torvalds 已提交
5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022
	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;
	}

5023
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036
	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;

5037
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5038 5039 5040 5041 5042 5043
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5044
	struct common_audit_data ad;
5045
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5046 5047 5048 5049 5050 5051 5052 5053
	int rc;

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

	isec = sma->sem_perm.security;

5054
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5055
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5056

5057
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073
			  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;
5074
	struct common_audit_data ad;
5075
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5076 5077 5078

	isec = sma->sem_perm.security;

5079
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
5080 5081
	ad.u.ipc_id = sma->sem_perm.key;

5082
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5083 5084 5085 5086 5087 5088 5089 5090 5091
			    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;

5092
	switch (cmd) {
L
Linus Torvalds 已提交
5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123
	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;
	}

5124
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137
	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;

5138
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153
}

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;

5154
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5155 5156
}

5157 5158 5159 5160 5161 5162
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5163
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5164 5165 5166 5167 5168 5169
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5170
			       char *name, char **value)
L
Linus Torvalds 已提交
5171
{
5172
	const struct task_security_struct *__tsec;
5173
	u32 sid;
L
Linus Torvalds 已提交
5174
	int error;
5175
	unsigned len;
L
Linus Torvalds 已提交
5176 5177

	if (current != p) {
5178
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5179 5180 5181 5182
		if (error)
			return error;
	}

5183 5184
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5185 5186

	if (!strcmp(name, "current"))
5187
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5188
	else if (!strcmp(name, "prev"))
5189
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5190
	else if (!strcmp(name, "exec"))
5191
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5192
	else if (!strcmp(name, "fscreate"))
5193
		sid = __tsec->create_sid;
5194
	else if (!strcmp(name, "keycreate"))
5195
		sid = __tsec->keycreate_sid;
5196
	else if (!strcmp(name, "sockcreate"))
5197
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5198
	else
5199 5200
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5201 5202 5203 5204

	if (!sid)
		return 0;

5205 5206 5207 5208
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5209 5210 5211 5212

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5213 5214 5215 5216 5217 5218
}

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
5219
	struct task_struct *tracer;
D
David Howells 已提交
5220 5221
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236
	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"))
5237
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5238
	else if (!strcmp(name, "fscreate"))
5239
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5240
	else if (!strcmp(name, "keycreate"))
5241
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5242
	else if (!strcmp(name, "sockcreate"))
5243
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5244
	else if (!strcmp(name, "current"))
5245
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257
	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);
5258 5259 5260 5261 5262 5263
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5264 5265 5266 5267
		if (error)
			return error;
	}

D
David Howells 已提交
5268 5269 5270 5271
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5272 5273 5274
	/* 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
5275
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5276 5277
	   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
5278 5279
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5280
		tsec->exec_sid = sid;
D
David Howells 已提交
5281
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5282
		tsec->create_sid = sid;
D
David Howells 已提交
5283
	} else if (!strcmp(name, "keycreate")) {
5284 5285
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5286
			goto abort_change;
5287
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5288
	} else if (!strcmp(name, "sockcreate")) {
5289
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5290 5291
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5292
		if (sid == 0)
D
David Howells 已提交
5293 5294 5295 5296
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5297
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5298 5299 5300
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5301
		}
L
Linus Torvalds 已提交
5302 5303 5304

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5305
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5306
		if (error)
D
David Howells 已提交
5307
			goto abort_change;
L
Linus Torvalds 已提交
5308 5309 5310

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5311
		ptsid = 0;
L
Linus Torvalds 已提交
5312
		task_lock(p);
5313
		tracer = ptrace_parent(p);
D
David Howells 已提交
5314 5315 5316 5317 5318 5319 5320
		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
5321
			if (error)
D
David Howells 已提交
5322
				goto abort_change;
L
Linus Torvalds 已提交
5323 5324
		}

D
David Howells 已提交
5325 5326 5327 5328 5329 5330 5331
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5332
	return size;
D
David Howells 已提交
5333 5334 5335 5336

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5337 5338
}

5339 5340 5341 5342 5343
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5344
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5345 5346 5347 5348
{
	return security_context_to_sid(secdata, seclen, secid);
}

5349 5350
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5351
	kfree(secdata);
5352 5353
}

5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379
/*
 *	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;
}
5380 5381
#ifdef CONFIG_KEYS

D
David Howells 已提交
5382
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5383
			     unsigned long flags)
5384
{
D
David Howells 已提交
5385
	const struct task_security_struct *tsec;
5386 5387 5388 5389 5390 5391
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5392 5393 5394
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5395
	else
D
David Howells 已提交
5396
		ksec->sid = tsec->sid;
5397

5398
	k->security = ksec;
5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410
	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
5411 5412
				  const struct cred *cred,
				  key_perm_t perm)
5413 5414 5415
{
	struct key *key;
	struct key_security_struct *ksec;
5416
	u32 sid;
5417 5418 5419 5420 5421 5422 5423

	/* 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
5424
	sid = cred_sid(cred);
5425 5426 5427 5428 5429

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5430 5431
}

5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445
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;
}

5446 5447
#endif

L
Linus Torvalds 已提交
5448
static struct security_operations selinux_ops = {
5449 5450
	.name =				"selinux",

5451
	.ptrace_access_check =		selinux_ptrace_access_check,
5452
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5453
	.capget =			selinux_capget,
D
David Howells 已提交
5454
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5455 5456 5457 5458 5459 5460 5461
	.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,
5462
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5463

5464 5465 5466
	.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
5467 5468 5469 5470 5471
	.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,
5472
	.sb_remount =			selinux_sb_remount,
5473
	.sb_kern_mount =		selinux_sb_kern_mount,
5474
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5475 5476 5477
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5478
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5479
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5480 5481
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5482 5483 5484

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5485
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503
	.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,
5504 5505 5506
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5507
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520

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

5521
	.dentry_open =			selinux_dentry_open,
5522

L
Linus Torvalds 已提交
5523
	.task_create =			selinux_task_create,
5524
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5525
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5526
	.cred_prepare =			selinux_cred_prepare,
5527
	.cred_transfer =		selinux_cred_transfer,
5528 5529
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5530
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5531 5532
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5533
	.task_getsid =			selinux_task_getsid,
5534
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5535
	.task_setnice =			selinux_task_setnice,
5536
	.task_setioprio =		selinux_task_setioprio,
5537
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5538 5539 5540
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5541
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5542 5543
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5544
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5545 5546

	.ipc_permission =		selinux_ipc_permission,
5547
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564

	.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,

5565 5566
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5567 5568 5569 5570
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5571
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5572

5573 5574
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5575

5576
	.secid_to_secctx =		selinux_secid_to_secctx,
5577
	.secctx_to_secid =		selinux_secctx_to_secid,
5578
	.release_secctx =		selinux_release_secctx,
5579 5580 5581
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5582

5583
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599
	.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
5600 5601
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5602 5603
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5604
	.sk_clone_security =		selinux_sk_clone_security,
5605
	.sk_getsecid =			selinux_sk_getsecid,
5606 5607 5608
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5609
	.inet_conn_established =	selinux_inet_conn_established,
5610 5611 5612
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5613
	.req_classify_flow =		selinux_req_classify_flow,
5614 5615 5616
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5617 5618 5619 5620 5621

#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
5622
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5623 5624
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5625
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5626
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5627 5628
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5629
#endif
5630 5631

#ifdef CONFIG_KEYS
5632 5633 5634
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5635
	.key_getsecurity =		selinux_key_getsecurity,
5636
#endif
5637 5638 5639 5640 5641 5642 5643

#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
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5644 5645 5646 5647
};

static __init int selinux_init(void)
{
5648 5649 5650 5651 5652
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5653 5654 5655 5656 5657 5658 5659 5660
	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
5661
	cred_init_security();
L
Linus Torvalds 已提交
5662

5663 5664
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5665 5666
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5667
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5668 5669
	avc_init();

5670
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5671 5672
		panic("SELinux: Unable to register with kernel.\n");

5673
	if (selinux_enforcing)
5674
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5675
	else
5676
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5677

L
Linus Torvalds 已提交
5678 5679 5680
	return 0;
}

5681 5682 5683 5684 5685
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5686 5687
void selinux_complete_init(void)
{
5688
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5689 5690

	/* Set up any superblocks initialized prior to the policy load. */
5691
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5692
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5693 5694 5695 5696 5697 5698
}

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

5699
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5700

5701 5702 5703 5704 5705 5706 5707 5708 5709 5710 5711 5712 5713 5714
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5715 5716 5717 5718 5719 5720 5721
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5722
	}
L
Linus Torvalds 已提交
5723 5724 5725 5726
};

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

5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737 5738 5739 5740 5741
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5742 5743 5744 5745 5746 5747 5748 5749 5750 5751
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5752 5753 5754

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

5755 5756 5757
	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
5758 5759

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5760 5761 5762
	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
5763
#endif	/* IPV6 */
5764

L
Linus Torvalds 已提交
5765 5766 5767 5768 5769 5770 5771 5772 5773
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5774
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5775

5776
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5777
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5778
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5779 5780 5781 5782
#endif	/* IPV6 */
}
#endif

5783
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5784 5785 5786 5787 5788

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5789
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5790 5791

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5792 5793
static int selinux_disabled;

L
Linus Torvalds 已提交
5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808
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;
5809
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5810

5811
	reset_security_ops();
L
Linus Torvalds 已提交
5812

5813 5814 5815
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5816 5817 5818 5819 5820 5821 5822 5823 5824
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif