hooks.c 136.3 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
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 *		Paul Moore <paul.moore@hp.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

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

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

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

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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


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

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

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

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

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

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

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

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

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

	return tsec->sid;
}

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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	selinux_netlbl_sk_security_reset(ssec);
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	return 0;
}

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

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

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

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

static char *labeling_behaviors[6] = {
	"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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	/* 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)
{
575 576
	char mnt_flags = sbsec->flags & SE_MNTMASK;

577
	/* check if the old mount command had the same options */
578
	if (sbsec->flags & SE_SBINITIALIZED)
579 580 581 582 583 584 585
		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
	 */
586 587
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
588 589 590
			return 1;
	return 0;
}
591

592 593 594 595
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
596 597
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
598
{
599
	const struct cred *cred = current_cred();
600 601 602
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
603 604
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
605 606
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
607 608 609
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
610 611 612 613 614 615 616 617 618 619 620 621 622 623 624

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			spin_lock(&sb_security_lock);
			if (list_empty(&sbsec->list))
				list_add(&sbsec->list, &superblock_security_head);
			spin_unlock(&sb_security_lock);
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
625 626
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
627
		goto out;
628
	}
L
Linus Torvalds 已提交
629

630 631 632 633 634 635 636 637 638 639 640
	/*
	 * 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)
	 */
641
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642
	    && (num_opts == 0))
643
		goto out;
644

645 646 647 648 649 650 651
	/*
	 * 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;
652 653 654

		if (flags[i] == SE_SBLABELSUPP)
			continue;
655 656
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
657 658 659
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704
			       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
705
		}
706 707
	}

708
	if (sbsec->flags & SE_SBINITIALIZED) {
709
		/* previously mounted with options, but not on this attempt? */
710
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
711 712 713 714 715
			goto out_double_mount;
		rc = 0;
		goto out;
	}

716
	if (strcmp(sb->s_type->name, "proc") == 0)
717
		sbsec->flags |= SE_SBPROC;
718 719

	/* Determine the labeling behavior to use for this filesystem type. */
720
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
721 722
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
723
		       __func__, sb->s_type->name, rc);
724 725
		goto out;
	}
L
Linus Torvalds 已提交
726

727 728
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
729
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
730
		if (rc)
731
			goto out;
L
Linus Torvalds 已提交
732

733
		sbsec->sid = fscontext_sid;
734 735 736 737 738 739 740
	}

	/*
	 * 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.
	 */
741 742
	if (context_sid) {
		if (!fscontext_sid) {
743 744
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
745
			if (rc)
746 747
				goto out;
			sbsec->sid = context_sid;
748
		} else {
749 750
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
751
			if (rc)
752
				goto out;
753
		}
754 755
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
756

757
		sbsec->mntpoint_sid = context_sid;
758
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
759 760
	}

761
	if (rootcontext_sid) {
762 763
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
764
		if (rc)
765
			goto out;
766

767 768
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
769 770
	}

771 772 773 774 775 776
	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
777 778
		}

779 780
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
781
							     sbsec, cred);
782 783 784
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
785

786
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
787 788
	}

789
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
790
out:
791
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
792
	return rc;
793 794 795 796 797
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
798 799
}

800 801
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
802
{
803 804
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
805

806 807 808
	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
809

810 811 812 813 814 815 816 817 818 819 820 821
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
	 * mount options.  thus we can safely put this sb on the list and deal
	 * with it later
	 */
	if (!ss_initialized) {
		spin_lock(&sb_security_lock);
		if (list_empty(&newsbsec->list))
			list_add(&newsbsec->list, &superblock_security_head);
		spin_unlock(&sb_security_lock);
		return;
	}
822 823

	/* how can we clone if the old one wasn't set up?? */
824
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
825

826
	/* if fs is reusing a sb, just let its options stand... */
827
	if (newsbsec->flags & SE_SBINITIALIZED)
828 829
		return;

830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848
	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
849
	}
850 851 852 853 854
	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
855

856
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
857 858
	}

859 860 861 862
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

863 864
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
865
{
866
	char *p;
867 868
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
869
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
870

871
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
872

873 874 875 876
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
877

878 879
		if (!*p)
			continue;
L
Linus Torvalds 已提交
880

881
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
882

883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934
		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;
935 936
		case Opt_labelsupport:
			break;
937 938 939 940
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
941 942 943

		}
	}
944

945 946 947 948 949 950 951 952 953 954 955
	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;
	}

956
	if (fscontext) {
957 958
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
959 960
	}
	if (context) {
961 962
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
963 964
	}
	if (rootcontext) {
965 966
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
967 968
	}
	if (defcontext) {
969 970
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
971 972
	}

973 974 975
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

976 977 978 979 980
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
981 982
	return rc;
}
983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009
/*
 * 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
1010

A
Adrian Bunk 已提交
1011 1012
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1013 1014 1015 1016 1017
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1018 1019 1020 1021 1022 1023
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037

		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;
1038 1039 1040 1041
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061
		default:
			BUG();
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
		seq_puts(m, opts->mnt_opts[i]);
		if (has_comma)
			seq_putc(m, '\"');
	}
}

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

	rc = selinux_get_mnt_opts(sb, &opts);
1062 1063 1064 1065
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1066
		return rc;
1067
	}
1068 1069 1070 1071 1072 1073 1074 1075

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098
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;
}

1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
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
1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124
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:
1125 1126 1127 1128
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1129
		case SOCK_DGRAM:
1130 1131 1132 1133
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1134 1135
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1136
		default:
L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142 1143 1144 1145
			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;
1146
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159
			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;
1160 1161
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1162 1163 1164 1165 1166 1167 1168
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1169 1170
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183
	}

	return SECCLASS_SOCKET;
}

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

1184
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
	if (!buffer)
		return -ENOMEM;

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

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

	if (isec->initialized)
		goto out;

1232
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1233
	if (isec->initialized)
1234
		goto out_unlock;
L
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1235 1236

	sbsec = inode->i_sb->s_security;
1237
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1238 1239 1240 1241 1242 1243 1244
		/* 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);
1245
		goto out_unlock;
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1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264
	}

	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) {
1265 1266 1267 1268 1269 1270 1271 1272 1273
			/*
			 * 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.
			 */
1274
			goto out_unlock;
L
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1275 1276 1277
		}

		len = INITCONTEXTLEN;
1278
		context = kmalloc(len+1, GFP_NOFS);
L
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1279 1280 1281
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1282
			goto out_unlock;
L
Linus Torvalds 已提交
1283
		}
1284
		context[len] = '\0';
L
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1285 1286 1287 1288 1289 1290 1291 1292
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
			/* 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);
1293
				goto out_unlock;
L
Linus Torvalds 已提交
1294 1295 1296
			}
			kfree(context);
			len = rc;
1297
			context = kmalloc(len+1, GFP_NOFS);
L
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1298 1299 1300
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1301
				goto out_unlock;
L
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1302
			}
1303
			context[len] = '\0';
L
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			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
1311
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1312
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1313 1314
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1315
				goto out_unlock;
L
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1316 1317 1318 1319 1320
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1321
			rc = security_context_to_sid_default(context, rc, &sid,
1322 1323
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1324
			if (rc) {
1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337
				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);
				}
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1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		isec->sid = sid;
		break;
	case SECURITY_FS_USE_TASK:
		isec->sid = isec->task_sid;
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
		isec->sid = sbsec->sid;

		/* Try to obtain a transition SID. */
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		rc = security_transition_sid(isec->task_sid,
					     sbsec->sid,
					     isec->sclass,
					     &sid);
		if (rc)
1361
			goto out_unlock;
L
Linus Torvalds 已提交
1362 1363
		isec->sid = sid;
		break;
1364 1365 1366
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
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1367
	default:
1368
		/* Default to the fs superblock SID. */
L
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1369 1370
		isec->sid = sbsec->sid;

1371
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
L
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1372 1373 1374 1375 1376 1377 1378
			struct proc_inode *proci = PROC_I(inode);
			if (proci->pde) {
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
				rc = selinux_proc_get_sid(proci->pde,
							  isec->sclass,
							  &sid);
				if (rc)
1379
					goto out_unlock;
L
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1380 1381 1382 1383 1384 1385 1386 1387
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1388 1389
out_unlock:
	mutex_unlock(&isec->lock);
L
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1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422
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
1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
/*
 * 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);
}

1436
/*
1437
 * Check permission between a pair of tasks, e.g. signal checks,
1438 1439
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1440
 * - this uses the default subjective creds of tsk1
1441 1442 1443
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1444 1445
			 u32 perms)
{
1446 1447
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1448

1449 1450 1451 1452 1453
	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
1454 1455
}

1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471
/*
 * 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);
}

1472 1473 1474 1475
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1476 1477
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1478
			       const struct cred *cred,
1479
			       int cap, int audit)
L
Linus Torvalds 已提交
1480 1481
{
	struct avc_audit_data ad;
1482
	struct av_decision avd;
1483
	u16 sclass;
1484
	u32 sid = cred_sid(cred);
1485
	u32 av = CAP_TO_MASK(cap);
1486
	int rc;
L
Linus Torvalds 已提交
1487

1488
	AVC_AUDIT_DATA_INIT(&ad, CAP);
L
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1489 1490 1491
	ad.tsk = tsk;
	ad.u.cap = cap;

1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
	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();
	}
1504

1505
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1506
	if (audit == SECURITY_CAP_AUDIT)
1507
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1508
	return rc;
L
Linus Torvalds 已提交
1509 1510 1511 1512 1513 1514
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1515
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1516

1517
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1518 1519 1520 1521 1522 1523
			    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). */
1524
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1525 1526 1527 1528 1529 1530
			  struct inode *inode,
			  u32 perms,
			  struct avc_audit_data *adp)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
1531
	u32 sid;
L
Linus Torvalds 已提交
1532

1533
	if (unlikely(IS_PRIVATE(inode)))
1534 1535
		return 0;

1536
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1537 1538 1539 1540 1541 1542 1543 1544
	isec = inode->i_security;

	if (!adp) {
		adp = &ad;
		AVC_AUDIT_DATA_INIT(&ad, FS);
		ad.u.fs.inode = inode;
	}

1545
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1546 1547 1548 1549 1550
}

/* 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. */
1551
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1552 1553 1554 1555 1556 1557
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
	struct avc_audit_data ad;
1558

1559
	AVC_AUDIT_DATA_INIT(&ad, FS);
1560 1561
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1562
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1563 1564 1565 1566 1567 1568 1569 1570 1571 1572
}

/* 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. */
1573 1574 1575
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1576 1577
{
	struct file_security_struct *fsec = file->f_security;
1578
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1579
	struct avc_audit_data ad;
1580
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1581 1582 1583
	int rc;

	AVC_AUDIT_DATA_INIT(&ad, FS);
1584
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1585

1586 1587
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1588 1589 1590 1591
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1592
			goto out;
L
Linus Torvalds 已提交
1593 1594 1595
	}

	/* av is zero if only checking access to the descriptor. */
1596
	rc = 0;
L
Linus Torvalds 已提交
1597
	if (av)
1598
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1599

1600 1601
out:
	return rc;
L
Linus Torvalds 已提交
1602 1603 1604 1605 1606 1607 1608
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1609 1610
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1611 1612
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1613
	u32 sid, newsid;
L
Linus Torvalds 已提交
1614 1615 1616 1617 1618 1619
	struct avc_audit_data ad;
	int rc;

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

1620 1621 1622
	sid = tsec->sid;
	newsid = tsec->create_sid;

L
Linus Torvalds 已提交
1623
	AVC_AUDIT_DATA_INIT(&ad, FS);
1624
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1625

1626
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1627 1628 1629 1630 1631
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1632
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1633
		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
L
Linus Torvalds 已提交
1634 1635 1636 1637
		if (rc)
			return rc;
	}

1638
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1639 1640 1641 1642 1643 1644 1645 1646
	if (rc)
		return rc;

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

1647 1648 1649 1650
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1651
	u32 sid = task_sid(ctx);
1652

1653
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1654 1655
}

1656 1657 1658
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1659 1660 1661 1662 1663 1664 1665 1666 1667

/* 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;
	struct avc_audit_data ad;
1668
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1669 1670 1671 1672 1673 1674 1675
	u32 av;
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, FS);
1676
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1677 1678 1679

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1680
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694
	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
1695 1696
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1697 1698 1699
		return 0;
	}

1700
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1701 1702 1703 1704 1705 1706 1707 1708 1709 1710
	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;
	struct avc_audit_data ad;
1711
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722
	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;

	AVC_AUDIT_DATA_INIT(&ad, FS);

1723
	ad.u.fs.path.dentry = old_dentry;
1724
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1725 1726 1727
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1728
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1729 1730 1731 1732
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1733
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1734 1735 1736 1737 1738
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1739
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1740 1741 1742
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1743
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1744 1745 1746 1747 1748
	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);
1749
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
				  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. */
1760
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1761 1762 1763 1764 1765
			       struct super_block *sb,
			       u32 perms,
			       struct avc_audit_data *ad)
{
	struct superblock_security_struct *sbsec;
1766
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1767 1768

	sbsec = sb->s_security;
1769
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799
}

/* 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;
}

1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822
/* 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
1823
/*
1824
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1825 1826
 * open permission.
 */
1827
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1828
{
1829
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1830 1831

	if (selinux_policycap_openperm) {
1832
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845
		/*
		 * lnk files and socks do not really have an 'open'
		 */
		if (S_ISREG(mode))
			av |= FILE__OPEN;
		else if (S_ISCHR(mode))
			av |= CHR_FILE__OPEN;
		else if (S_ISBLK(mode))
			av |= BLK_FILE__OPEN;
		else if (S_ISFIFO(mode))
			av |= FIFO_FILE__OPEN;
		else if (S_ISDIR(mode))
			av |= DIR__OPEN;
E
Eric Paris 已提交
1846 1847
		else if (S_ISSOCK(mode))
			av |= SOCK_FILE__OPEN;
E
Eric Paris 已提交
1848
		else
E
Eric Paris 已提交
1849
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1850
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1851 1852 1853 1854
	}
	return av;
}

L
Linus Torvalds 已提交
1855 1856
/* Hook functions begin here. */

1857 1858
static int selinux_ptrace_may_access(struct task_struct *child,
				     unsigned int mode)
L
Linus Torvalds 已提交
1859 1860 1861
{
	int rc;

1862
	rc = cap_ptrace_may_access(child, mode);
L
Linus Torvalds 已提交
1863 1864 1865
	if (rc)
		return rc;

1866
	if (mode == PTRACE_MODE_READ) {
1867 1868 1869
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1870 1871
	}

1872
	return current_has_perm(child, PROCESS__PTRACE);
1873 1874 1875 1876 1877 1878
}

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

1879
	rc = cap_ptrace_traceme(parent);
1880 1881 1882 1883
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1884 1885 1886
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1887
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1888 1889 1890
{
	int error;

1891
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1892 1893 1894
	if (error)
		return error;

1895
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1896 1897
}

D
David Howells 已提交
1898 1899 1900 1901
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
1902 1903 1904
{
	int error;

1905
	error = cap_capset(new, old,
D
David Howells 已提交
1906
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1907 1908 1909
	if (error)
		return error;

D
David Howells 已提交
1910
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1911 1912
}

1913 1914 1915 1916 1917 1918 1919 1920 1921 1922
/*
 * (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.
 */

1923 1924
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
			   int cap, int audit)
L
Linus Torvalds 已提交
1925 1926 1927
{
	int rc;

1928
	rc = cap_capable(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1929 1930 1931
	if (rc)
		return rc;

1932
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1933 1934
}

1935 1936 1937 1938 1939 1940
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1941
	buffer = (char *)__get_free_page(GFP_KERNEL);
1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962
	if (!buffer)
		goto out;

	buflen = PAGE_SIZE;
	end = buffer+buflen;
	*--end = '\0';
	buflen--;
	path = end-1;
	*path = '/';
	while (table) {
		const char *name = table->procname;
		size_t namelen = strlen(name);
		buflen -= namelen + 1;
		if (buflen < 0)
			goto out_free;
		end -= namelen;
		memcpy(end, name, namelen);
		*--end = '/';
		path = end;
		table = table->parent;
	}
1963 1964 1965 1966 1967 1968
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1969 1970 1971 1972 1973 1974 1975
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1976 1977 1978 1979
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1980
	u32 tsid, sid;
L
Linus Torvalds 已提交
1981 1982 1983 1984 1985 1986
	int rc;

	rc = secondary_ops->sysctl(table, op);
	if (rc)
		return rc;

1987
	sid = current_sid();
L
Linus Torvalds 已提交
1988

1989 1990
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1991 1992 1993 1994 1995 1996 1997
	if (rc) {
		/* Default to the well-defined sysctl SID. */
		tsid = SECINITSID_SYSCTL;
	}

	/* The op values are "defined" in sysctl.c, thereby creating
	 * a bad coupling between this module and sysctl.c */
1998
	if (op == 001) {
1999
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
2000 2001 2002 2003 2004 2005 2006 2007
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
2008
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
2009
					     SECCLASS_FILE, av, NULL);
2010
	}
L
Linus Torvalds 已提交
2011 2012 2013 2014 2015 2016

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2017
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2018 2019 2020 2021 2022 2023
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2024 2025 2026 2027 2028
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2029
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2030 2031 2032 2033
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2034
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2035 2036 2037 2038
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2039 2040 2041 2042 2043 2044
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2045 2046 2047
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2048 2049 2050 2051 2052 2053
}

static int selinux_syslog(int type)
{
	int rc;

2054
	rc = cap_syslog(type);
L
Linus Torvalds 已提交
2055 2056 2057 2058
	if (rc)
		return rc;

	switch (type) {
2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075
	case 3:		/* Read last kernel messages */
	case 10:	/* Return size of the log buffer */
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
	case 6:		/* Disable logging to console */
	case 7:		/* Enable logging to console */
	case 8:		/* Set level of messages printed to console */
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
	case 0:		/* Close log */
	case 1:		/* Open log */
	case 2:		/* Read from log */
	case 4:		/* Read/clear last kernel messages */
	case 5:		/* Clear ring buffer */
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087
	}
	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.
 */
2088
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2089 2090 2091
{
	int rc, cap_sys_admin = 0;

2092 2093
	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2094 2095 2096
	if (rc == 0)
		cap_sys_admin = 1;

2097
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2098 2099 2100 2101
}

/* binprm security operations */

2102
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2103
{
2104 2105
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2106 2107
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
2108
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2109 2110
	int rc;

2111
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2112 2113 2114
	if (rc)
		return rc;

2115 2116 2117
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2118 2119
		return 0;

2120 2121
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2122 2123 2124
	isec = inode->i_security;

	/* Default to the current task SID. */
2125 2126
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2127

2128
	/* Reset fs, key, and sock SIDs on execve. */
2129 2130 2131
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2132

2133 2134
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2135
		/* Reset exec SID on execve. */
2136
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2137 2138
	} else {
		/* Check for a default transition on this program. */
2139 2140
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2141 2142 2143 2144 2145
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, FS);
2146
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2147

J
Josef Sipek 已提交
2148
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2149
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2150

2151 2152
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2153 2154 2155 2156 2157
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2158
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2159 2160 2161 2162
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2163
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2164 2165 2166 2167
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
					  SECCLASS_PROCESS, PROCESS__SHARE,
					  NULL);
			if (rc)
				return -EPERM;
		}

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

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

			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2201

2202 2203
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2204 2205 2206 2207 2208
	}

	return 0;
}

2209
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2210
{
2211 2212 2213
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2214 2215
	int atsecure = 0;

2216 2217 2218 2219
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2220 2221 2222
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2223
		atsecure = avc_has_perm(osid, sid,
2224 2225
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2226 2227
	}

2228
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2229 2230 2231 2232 2233 2234
}

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

/* Derived from fs/exec.c:flush_old_files. */
2235 2236
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2237 2238 2239
{
	struct avc_audit_data ad;
	struct file *file, *devnull = NULL;
2240
	struct tty_struct *tty;
2241
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2242
	long j = -1;
2243
	int drop_tty = 0;
L
Linus Torvalds 已提交
2244

2245
	tty = get_current_tty();
L
Linus Torvalds 已提交
2246 2247
	if (tty) {
		file_list_lock();
2248 2249 2250
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2251 2252 2253 2254 2255
			/* 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. */
2256 2257
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2258
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2259
					   FILE__READ | FILE__WRITE, NULL)) {
2260
				drop_tty = 1;
L
Linus Torvalds 已提交
2261 2262 2263
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2264
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2265
	}
2266 2267 2268
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2269 2270 2271

	/* Revalidate access to inherited open files. */

2272
	AVC_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2273 2274 2275 2276 2277 2278 2279 2280

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

		j++;
		i = j * __NFDBITS;
2281
		fdt = files_fdtable(files);
2282
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2283
			break;
2284
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2285 2286 2287
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2288
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2289 2290 2291 2292
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2293
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304
						  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) {
2305
						get_file(devnull);
L
Linus Torvalds 已提交
2306
					} else {
2307 2308 2309 2310
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2311 2312
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2329 2330 2331 2332
/*
 * 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
2333
{
2334 2335 2336
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2337

2338 2339 2340
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2341

2342 2343
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2344

2345 2346
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2347

2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364
	/* Check whether the new SID can inherit resource limits from the old
	 * SID.  If not, reset all soft limits to the lower of the current
	 * task's hard limit and the init task's soft limit.
	 *
	 * Note that the setting of hard limits (even to lower them) can be
	 * controlled by the setrlimit check.  The inclusion of the init task's
	 * soft limit into the computation is to avoid resetting soft limits
	 * higher than the default soft limit for cases where the default is
	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
	 */
	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
		for (i = 0; i < RLIM_NLIMITS; i++) {
			rlim = current->signal->rlim + i;
			initrlim = init_task.signal->rlim + i;
			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
L
Linus Torvalds 已提交
2365
		}
2366
		update_rlimit_cpu(rlim->rlim_cur);
L
Linus Torvalds 已提交
2367 2368 2369 2370
	}
}

/*
2371 2372
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2373
 */
2374
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2375
{
2376
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2377
	struct itimerval itimer;
2378
	struct sighand_struct *psig;
2379
	u32 osid, sid;
L
Linus Torvalds 已提交
2380
	int rc, i;
2381
	unsigned long flags;
L
Linus Torvalds 已提交
2382

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

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

2389 2390 2391 2392 2393 2394 2395 2396
	/* Check whether the new SID can inherit signal state from the old SID.
	 * If not, clear itimers to avoid subsequent signal generation and
	 * flush and unblock signals.
	 *
	 * This must occur _after_ the task SID has been updated so that any
	 * kill done after the flush will be checked against the new SID.
	 */
	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
L
Linus Torvalds 已提交
2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		flush_signals(current);
		spin_lock_irq(&current->sighand->siglock);
		flush_signal_handlers(current, 1);
		sigemptyset(&current->blocked);
		recalc_sigpending();
		spin_unlock_irq(&current->sighand->siglock);
	}

2409 2410
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2411 2412 2413
	read_lock_irq(&tasklist_lock);
	psig = current->parent->sighand;
	spin_lock_irqsave(&psig->siglock, flags);
L
Linus Torvalds 已提交
2414
	wake_up_interruptible(&current->parent->signal->wait_chldexit);
2415 2416
	spin_unlock_irqrestore(&psig->siglock, flags);
	read_unlock_irq(&tasklist_lock);
L
Linus Torvalds 已提交
2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440
}

/* 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)
{
2441 2442 2443
	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) ||
2444 2445
		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
2446 2447 2448 2449 2450 2451 2452
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2453
	} else
L
Linus Torvalds 已提交
2454 2455 2456 2457 2458
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2459 2460
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2461 2462 2463 2464 2465 2466
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2467
	} else
2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479
		*first = 0;

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

2480
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2481 2482 2483 2484
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2485
	int open_quote = 0;
L
Linus Torvalds 已提交
2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500

	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 {
2501 2502 2503 2504
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2505 2506 2507
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2508
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2509 2510 2511 2512 2513 2514 2515
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2516
	strcpy(in_save, nosec_save);
2517
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2518 2519 2520 2521
out:
	return rc;
}

2522
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2523
{
2524
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2525 2526 2527 2528 2529 2530 2531
	struct avc_audit_data ad;
	int rc;

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

2532 2533 2534 2535
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2536
	AVC_AUDIT_DATA_INIT(&ad, FS);
2537
	ad.u.fs.path.dentry = sb->s_root;
2538
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2539 2540
}

2541
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2542
{
2543
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2544 2545
	struct avc_audit_data ad;

2546
	AVC_AUDIT_DATA_INIT(&ad, FS);
2547
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2548
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2549 2550
}

2551
static int selinux_mount(char *dev_name,
2552
			 struct path *path,
2553 2554 2555
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2556
{
2557
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2558 2559

	if (flags & MS_REMOUNT)
2560
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2561
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2562
	else
2563
		return dentry_has_perm(cred, path->mnt, path->dentry,
2564
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2565 2566 2567 2568
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2569
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2570

2571
	return superblock_has_perm(cred, mnt->mnt_sb,
2572
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586
}

/* 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);
}

2587 2588 2589 2590
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2591 2592
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2593 2594
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2595
	u32 sid, newsid, clen;
2596
	int rc;
2597
	char *namep = NULL, *context;
2598 2599 2600 2601

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

2602 2603 2604
	sid = tsec->sid;
	newsid = tsec->create_sid;

2605
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2606
		rc = security_transition_sid(sid, dsec->sid,
2607 2608 2609 2610 2611 2612
					     inode_mode_to_security_class(inode->i_mode),
					     &newsid);
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2613
			       __func__,
2614 2615 2616 2617 2618
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2619
	/* Possibly defer initialization to selinux_complete_init. */
2620
	if (sbsec->flags & SE_SBINITIALIZED) {
2621 2622 2623 2624 2625
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2626

2627
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2628 2629
		return -EOPNOTSUPP;

2630
	if (name) {
2631
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2632 2633 2634 2635
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2636

2637
	if (value && len) {
2638
		rc = security_sid_to_context_force(newsid, &context, &clen);
2639 2640 2641 2642 2643 2644
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2645 2646 2647 2648 2649
	}

	return 0;
}

L
Linus Torvalds 已提交
2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685
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,
2686
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2687 2688 2689 2690 2691 2692
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2693 2694 2695
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2696 2697 2698 2699
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2700
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2701

2702
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2703 2704
}

2705
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2706
{
2707
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2708 2709 2710 2711 2712 2713

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

2714
	return inode_has_perm(cred, inode,
2715
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2716 2717 2718 2719
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2720
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2721 2722 2723 2724 2725 2726

	if (iattr->ia_valid & ATTR_FORCE)
		return 0;

	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2727
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2728

2729
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2730 2731 2732 2733
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2734 2735 2736
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2737 2738
}

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

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

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

2760 2761
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
				  const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2762 2763 2764 2765 2766
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
	struct avc_audit_data ad;
2767
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2768 2769
	int rc = 0;

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

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

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

2780
	AVC_AUDIT_DATA_INIT(&ad, FS);
2781
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2782

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

	rc = security_context_to_sid(value, size, &newsid);
2789 2790 2791 2792 2793
	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
2794 2795 2796
	if (rc)
		return rc;

2797
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2798 2799 2800 2801
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2802
	rc = security_validate_transition(isec->sid, newsid, sid,
2803
					  isec->sclass);
L
Linus Torvalds 已提交
2804 2805 2806 2807 2808 2809 2810 2811 2812 2813
	if (rc)
		return rc;

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

2814
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2815
					const void *value, size_t size,
2816
					int flags)
L
Linus Torvalds 已提交
2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827
{
	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;
	}

2828
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2829
	if (rc) {
2830 2831 2832
		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
2833 2834 2835 2836 2837 2838 2839
		return;
	}

	isec->sid = newsid;
	return;
}

2840
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2841
{
2842 2843 2844
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2845 2846
}

2847
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2848
{
2849 2850 2851
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2852 2853
}

2854
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2855
{
2856 2857
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2858 2859 2860 2861 2862 2863

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

2864
/*
2865
 * Copy the inode security context value to the user.
2866 2867 2868
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2869
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2870
{
2871 2872 2873
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2874
	struct inode_security_struct *isec = inode->i_security;
2875

2876 2877
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2878

2879 2880 2881 2882 2883 2884 2885 2886 2887
	/*
	 * 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.
	 */
2888 2889
	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
				SECURITY_CAP_NOAUDIT);
2890 2891 2892 2893 2894
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2895 2896 2897 2898 2899 2900 2901 2902 2903 2904
	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
2905 2906 2907
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2908
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919
{
	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;

2920
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935
	if (rc)
		return rc;

	isec->sid = newsid;
	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;
}

2936 2937 2938 2939 2940 2941
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
2942 2943
/* file security operations */

2944
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2945
{
2946
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2947
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2948 2949 2950 2951 2952 2953 2954 2955 2956 2957

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

	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
		mask |= MAY_APPEND;

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

2962 2963
static int selinux_file_permission(struct file *file, int mask)
{
2964
	if (!mask)
2965 2966 2967 2968 2969 2970
		/* No permission to check.  Existence test. */
		return 0;

	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983
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)
{
2984
	const struct cred *cred = current_cred();
2985
	u32 av = 0;
L
Linus Torvalds 已提交
2986

2987 2988 2989 2990 2991 2992
	if (_IOC_DIR(cmd) & _IOC_WRITE)
		av |= FILE__WRITE;
	if (_IOC_DIR(cmd) & _IOC_READ)
		av |= FILE__READ;
	if (!av)
		av = FILE__IOCTL;
L
Linus Torvalds 已提交
2993

2994
	return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
2995 2996 2997 2998
}

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
2999
	const struct cred *cred = current_cred();
D
David Howells 已提交
3000
	int rc = 0;
3001

L
Linus Torvalds 已提交
3002 3003 3004 3005 3006 3007 3008
#ifndef CONFIG_PPC32
	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
D
David Howells 已提交
3009
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3010
		if (rc)
D
David Howells 已提交
3011
			goto error;
L
Linus Torvalds 已提交
3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025
	}
#endif

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

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

		if (prot & PROT_EXEC)
			av |= FILE__EXECUTE;

3026
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3027
	}
D
David Howells 已提交
3028 3029 3030

error:
	return rc;
L
Linus Torvalds 已提交
3031 3032 3033
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3034 3035
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3036
{
3037
	int rc = 0;
3038
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3039

3040 3041 3042 3043
	if (addr < mmap_min_addr)
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
	if (rc || addr_only)
L
Linus Torvalds 已提交
3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056
		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)
{
3057
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3058 3059 3060 3061 3062

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3063
	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3064
		int rc = 0;
3065 3066
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3067
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3068 3069 3070
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3071
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3072 3073 3074 3075 3076 3077 3078 3079
		} 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
3080
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3081
		}
3082 3083 3084
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3085 3086 3087 3088 3089 3090 3091
#endif

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

static int selinux_file_lock(struct file *file, unsigned int cmd)
{
3092 3093 3094
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3095 3096 3097 3098 3099
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3100
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3101 3102 3103
	int err = 0;

	switch (cmd) {
3104 3105 3106 3107 3108
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3109

3110
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3111
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3112
			break;
3113 3114 3115 3116 3117 3118 3119 3120
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3121
		err = file_has_perm(cred, file, 0);
3122 3123 3124 3125
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3126
#if BITS_PER_LONG == 32
3127 3128 3129
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3130
#endif
3131 3132
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3133
			break;
3134
		}
3135
		err = file_has_perm(cred, file, FILE__LOCK);
3136
		break;
L
Linus Torvalds 已提交
3137 3138 3139 3140 3141 3142 3143 3144 3145 3146
	}

	return err;
}

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

	fsec = file->f_security;
3147
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3148 3149 3150 3151 3152 3153 3154

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3155
	struct file *file;
3156
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3157 3158 3159 3160
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3161
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3162 3163 3164 3165 3166 3167 3168 3169

	fsec = file->f_security;

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

3170
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3171 3172 3173 3174 3175
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3176 3177 3178
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3179 3180
}

3181
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3182 3183 3184 3185
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3186

3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206
	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.
	 */
3207
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3208 3209
}

L
Linus Torvalds 已提交
3210 3211 3212 3213
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3214
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3215 3216
}

D
David Howells 已提交
3217 3218 3219 3220
/*
 * 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
3221
{
D
David Howells 已提交
3222 3223 3224 3225
	struct task_security_struct *tsec = cred->security;
	cred->security = NULL;
	kfree(tsec);
}
L
Linus Torvalds 已提交
3226

D
David Howells 已提交
3227 3228 3229 3230 3231 3232 3233 3234
/*
 * 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
3235

D
David Howells 已提交
3236
	old_tsec = old->security;
L
Linus Torvalds 已提交
3237

D
David Howells 已提交
3238 3239 3240
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3241

D
David Howells 已提交
3242
	new->security = tsec;
L
Linus Torvalds 已提交
3243 3244 3245
	return 0;
}

3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289
/*
 * set the security data for a kernel service
 * - all the creation contexts are set to unlabelled
 */
static int selinux_kernel_act_as(struct cred *new, u32 secid)
{
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

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

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

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

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

L
Linus Torvalds 已提交
3290 3291
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3292
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3293 3294 3295 3296
}

static int selinux_task_getpgid(struct task_struct *p)
{
3297
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3298 3299 3300 3301
}

static int selinux_task_getsid(struct task_struct *p)
{
3302
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3303 3304
}

3305 3306
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3307
	*secid = task_sid(p);
3308 3309
}

L
Linus Torvalds 已提交
3310 3311 3312 3313
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3314
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3315 3316 3317
	if (rc)
		return rc;

3318
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3319 3320
}

3321 3322
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3323 3324
	int rc;

3325
	rc = cap_task_setioprio(p, ioprio);
3326 3327 3328
	if (rc)
		return rc;

3329
	return current_has_perm(p, PROCESS__SETSCHED);
3330 3331
}

3332 3333
static int selinux_task_getioprio(struct task_struct *p)
{
3334
	return current_has_perm(p, PROCESS__GETSCHED);
3335 3336
}

L
Linus Torvalds 已提交
3337 3338 3339 3340 3341 3342 3343
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
	struct rlimit *old_rlim = current->signal->rlim + resource;

	/* Control the ability to change the hard limit (whether
	   lowering or raising it), so that the hard limit can
	   later be used as a safe reset point for the soft limit
D
David Howells 已提交
3344
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3345
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3346
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3347 3348 3349 3350 3351 3352

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3353 3354
	int rc;

3355
	rc = cap_task_setscheduler(p, policy, lp);
3356 3357 3358
	if (rc)
		return rc;

3359
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3360 3361 3362 3363
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3364
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3365 3366
}

3367 3368
static int selinux_task_movememory(struct task_struct *p)
{
3369
	return current_has_perm(p, PROCESS__SETSCHED);
3370 3371
}

3372 3373
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3374 3375 3376 3377 3378 3379 3380 3381
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3382
	if (secid)
3383 3384
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3385
	else
3386
		rc = current_has_perm(p, perm);
3387
	return rc;
L
Linus Torvalds 已提交
3388 3389 3390 3391
}

static int selinux_task_wait(struct task_struct *p)
{
3392
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3393 3394 3395 3396 3397 3398
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3399
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3400

3401
	isec->sid = sid;
L
Linus Torvalds 已提交
3402 3403 3404 3405
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3406 3407
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3408 3409 3410 3411
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3412
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424
	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;

3425 3426 3427
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3428
	switch (ih->protocol) {
3429 3430
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3431

3432 3433
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3434 3435 3436 3437 3438 3439 3440 3441 3442

		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;
3443 3444 3445 3446 3447 3448 3449 3450
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3451
		offset += ihlen;
3452
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3453
		if (uh == NULL)
3454
			break;
L
Linus Torvalds 已提交
3455

3456 3457 3458 3459
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3460

J
James Morris 已提交
3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474
	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;
3475
	}
J
James Morris 已提交
3476

3477 3478 3479
	default:
		break;
	}
L
Linus Torvalds 已提交
3480 3481 3482 3483 3484 3485 3486
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3487 3488
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3489 3490 3491 3492 3493
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3494
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3495 3496 3497 3498 3499 3500 3501 3502 3503 3504
	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);
3505
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3506 3507 3508
	if (offset < 0)
		goto out;

3509 3510 3511
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3512 3513
	switch (nexthdr) {
	case IPPROTO_TCP: {
3514
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536

		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
3537 3538 3539 3540 3541 3542 3543 3544 3545 3546
	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;
3547
	}
J
James Morris 已提交
3548

L
Linus Torvalds 已提交
3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3560
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3561
{
3562 3563
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3564 3565 3566

	switch (ad->u.net.family) {
	case PF_INET:
3567
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3568 3569 3570 3571 3572
		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
3573 3574 3575

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3576
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3577 3578 3579 3580 3581
		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
3582 3583
#endif	/* IPV6 */
	default:
3584 3585
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3586 3587
	}

3588 3589 3590 3591
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3592
	return ret;
3593 3594 3595 3596 3597

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3598 3599
}

3600
/**
3601
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3602
 * @skb: the packet
3603
 * @family: protocol family
3604
 * @sid: the packet's peer label SID
3605 3606
 *
 * Description:
3607 3608 3609 3610 3611 3612
 * 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.
3613 3614
 *
 */
3615
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3616
{
3617
	int err;
3618 3619
	u32 xfrm_sid;
	u32 nlbl_sid;
3620
	u32 nlbl_type;
3621 3622

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3623
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3624

3625 3626 3627 3628 3629
	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");
3630
		return -EACCES;
3631
	}
3632 3633

	return 0;
3634 3635
}

L
Linus Torvalds 已提交
3636 3637 3638 3639 3640 3641
/* socket security operations */
static int socket_has_perm(struct task_struct *task, struct socket *sock,
			   u32 perms)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
3642
	u32 sid;
L
Linus Torvalds 已提交
3643 3644 3645 3646 3647 3648
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3649
	sid = task_sid(task);
L
Linus Torvalds 已提交
3650

3651
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3652
	ad.u.net.sk = sock->sk;
3653
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3654 3655 3656 3657 3658 3659 3660 3661

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3662 3663 3664 3665
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, newsid;
	u16 secclass;
L
Linus Torvalds 已提交
3666 3667 3668 3669 3670
	int err = 0;

	if (kern)
		goto out;

3671 3672 3673 3674 3675
	sid = tsec->sid;
	newsid = tsec->sockcreate_sid ?: sid;

	secclass = socket_type_to_security_class(family, type, protocol);
	err = avc_has_perm(sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3676 3677 3678 3679 3680

out:
	return err;
}

V
Venkat Yekkirala 已提交
3681 3682
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3683
{
3684 3685
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3686
	struct inode_security_struct *isec;
3687
	struct sk_security_struct *sksec;
3688 3689 3690 3691 3692
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3693 3694 3695

	isec = SOCK_INODE(sock)->i_security;

3696 3697 3698 3699 3700 3701 3702
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3703 3704 3705
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3706 3707 3708
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3709
		sksec->sclass = isec->sclass;
3710
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3711 3712
	}

V
Venkat Yekkirala 已提交
3713
	return err;
L
Linus Torvalds 已提交
3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730
}

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

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

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

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3731 3732
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3733 3734 3735 3736 3737 3738 3739 3740 3741 3742
	 */
	family = sock->sk->sk_family;
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
		struct inode_security_struct *isec;
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
		struct sock *sk = sock->sk;
3743
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756

		isec = SOCK_INODE(sock)->i_security;

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

3757 3758 3759 3760 3761 3762
		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
3763 3764
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3765 3766
				if (err)
					goto out;
3767
				AVC_AUDIT_DATA_INIT(&ad, NET);
3768 3769 3770 3771 3772 3773 3774 3775
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
				err = avc_has_perm(isec->sid, sid,
						   isec->sclass,
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3776
		}
3777 3778

		switch (isec->sclass) {
3779
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3780 3781
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3782

3783
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3784 3785
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3786 3787 3788 3789 3790

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3791 3792 3793 3794
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3795

3796
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3797 3798
		if (err)
			goto out;
3799 3800

		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3801 3802 3803 3804 3805 3806 3807 3808 3809
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

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

		err = avc_has_perm(isec->sid, sid,
3810
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3811 3812 3813 3814 3815 3816 3817 3818 3819
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3820
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3821 3822 3823 3824 3825 3826 3827 3828
	struct inode_security_struct *isec;
	int err;

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

	/*
J
James Morris 已提交
3829
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3830 3831
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3832 3833
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
L
Linus Torvalds 已提交
3834 3835 3836 3837
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3838
		u32 sid, perm;
L
Linus Torvalds 已提交
3839 3840 3841

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3842
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3843 3844 3845 3846
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3847
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3848 3849 3850 3851
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3852
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3853 3854 3855
		if (err)
			goto out;

J
James Morris 已提交
3856 3857 3858
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3859
		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3860 3861
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3862
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3863 3864 3865 3866
		if (err)
			goto out;
	}

3867 3868
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898
out:
	return err;
}

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

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

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

	newisec = SOCK_INODE(newsock)->i_security;

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

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3899
				  int size)
L
Linus Torvalds 已提交
3900
{
3901
	return socket_has_perm(current, sock, SOCKET__WRITE);
L
Linus Torvalds 已提交
3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919
}

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

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

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

3920
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3921
{
3922 3923 3924 3925 3926 3927 3928
	int err;

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

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954
}

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

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

static int selinux_socket_unix_stream_connect(struct socket *sock,
					      struct socket *other,
					      struct sock *newsk)
{
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
	struct avc_audit_data ad;
	int err;

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

3955
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966
	ad.u.net.sk = other->sk;

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

	/* connecting socket */
	ssec = sock->sk->sk_security;
	ssec->peer_sid = other_isec->sid;
3967

L
Linus Torvalds 已提交
3968 3969 3970
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
3971 3972 3973
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
	struct inode_security_struct *isec;
	struct inode_security_struct *other_isec;
	struct avc_audit_data ad;
	int err;

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

3987
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3988 3989 3990 3991 3992 3993 3994 3995 3996 3997
	ad.u.net.sk = other->sk;

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

	return 0;
}

3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
				    struct avc_audit_data *ad)
{
	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);
}

4021
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4022
				       u16 family)
4023
{
4024
	int err = 0;
4025 4026 4027
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4028 4029 4030 4031 4032 4033 4034 4035 4036
	struct avc_audit_data ad;
	char *addrp;

	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = skb->iif;
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4037

4038
	if (selinux_secmark_enabled()) {
4039
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4040
				   PACKET__RECV, &ad);
4041 4042 4043
		if (err)
			return err;
	}
4044 4045 4046 4047 4048 4049

	if (selinux_policycap_netpeer) {
		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
		if (err)
			return err;
		err = avc_has_perm(sk_sid, peer_sid,
4050
				   SECCLASS_PEER, PEER__RECV, &ad);
4051 4052
		if (err)
			selinux_netlbl_err(skb, err, 0);
4053
	} else {
4054
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4055 4056
		if (err)
			return err;
4057
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4058
	}
4059

4060 4061 4062 4063 4064
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4065
	int err;
4066
	struct sk_security_struct *sksec = sk->sk_security;
4067 4068 4069 4070
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
	struct avc_audit_data ad;
	char *addrp;
4071 4072
	u8 secmark_active;
	u8 peerlbl_active;
4073 4074

	if (family != PF_INET && family != PF_INET6)
4075
		return 0;
4076 4077

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4078
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4079 4080
		family = PF_INET;

4081 4082 4083 4084
	/* 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. */
4085
	if (!selinux_policycap_netpeer)
4086 4087 4088 4089 4090 4091 4092
		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;

4093
	AVC_AUDIT_DATA_INIT(&ad, NET);
4094
	ad.u.net.netif = skb->iif;
4095
	ad.u.net.family = family;
4096
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4097
	if (err)
4098
		return err;
4099

4100
	if (peerlbl_active) {
4101 4102 4103
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4104 4105 4106 4107
		if (err)
			return err;
		err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
					       peer_sid, &ad);
4108 4109
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4110
			return err;
4111
		}
4112 4113
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4114 4115
		if (err)
			selinux_netlbl_err(skb, err, 0);
4116 4117
	}

4118
	if (secmark_active) {
4119 4120 4121 4122 4123 4124
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4125
	return err;
L
Linus Torvalds 已提交
4126 4127
}

C
Catherine Zhang 已提交
4128 4129
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4130 4131 4132 4133 4134 4135
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4136
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4137 4138

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4139

4140 4141
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4142 4143 4144
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4145
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4146 4147 4148 4149
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4150 4151
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167
	if (err)
		goto out;

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

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

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

	kfree(scontext);
4168
out:
L
Linus Torvalds 已提交
4169 4170 4171
	return err;
}

4172
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4173
{
4174
	u32 peer_secid = SECSID_NULL;
4175
	u16 family;
C
Catherine Zhang 已提交
4176

4177 4178 4179 4180 4181
	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)
4182 4183 4184 4185 4186
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4187
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4188
	else if (skb)
4189
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4190

4191
out:
4192
	*secid = peer_secid;
4193 4194 4195
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4196 4197
}

A
Al Viro 已提交
4198
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4199 4200 4201 4202 4203 4204 4205 4206 4207
{
	return sk_alloc_security(sk, family, priority);
}

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

4208
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4209
{
4210 4211
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4212

4213 4214
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4215
	newssec->sclass = ssec->sclass;
4216

4217
	selinux_netlbl_sk_security_reset(newssec);
4218 4219
}

V
Venkat Yekkirala 已提交
4220
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4221
{
4222
	if (!sk)
V
Venkat Yekkirala 已提交
4223
		*secid = SECINITSID_ANY_SOCKET;
4224 4225
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4226

V
Venkat Yekkirala 已提交
4227
		*secid = sksec->sid;
4228
	}
4229 4230
}

4231
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4232 4233 4234 4235
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4236 4237 4238
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4239
	sksec->sclass = isec->sclass;
4240 4241
}

4242 4243
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4244 4245 4246
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4247
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4248
	u32 newsid;
4249 4250
	u32 peersid;

4251 4252 4253 4254 4255
	/* 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);
4256 4257
	if (err)
		return err;
4258 4259
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4260
		req->peer_secid = SECSID_NULL;
4261 4262 4263 4264 4265 4266
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4267 4268
	}

4269
	return selinux_netlbl_inet_conn_request(req, family);
4270 4271
}

4272 4273
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4274 4275 4276 4277
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4278
	newsksec->peer_sid = req->peer_secid;
4279 4280 4281 4282
	/* 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. */
4283

P
Paul Moore 已提交
4284 4285
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4286
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4287 4288
}

4289
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4290
{
4291
	u16 family = sk->sk_family;
4292 4293
	struct sk_security_struct *sksec = sk->sk_security;

4294 4295 4296 4297 4298
	/* 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);
4299 4300
}

4301 4302
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4303 4304 4305 4306
{
	fl->secid = req->secid;
}

L
Linus Torvalds 已提交
4307 4308 4309 4310 4311 4312 4313
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
	struct socket *sock = sk->sk_socket;
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
4314

L
Linus Torvalds 已提交
4315 4316 4317 4318
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4319
	nlh = nlmsg_hdr(skb);
4320

L
Linus Torvalds 已提交
4321 4322 4323
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4324
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4325 4326 4327
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4328
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344
				err = 0;
		}

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

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

#ifdef CONFIG_NETFILTER

4345 4346
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4347
{
4348
	int err;
4349 4350 4351 4352
	char *addrp;
	u32 peer_sid;
	struct avc_audit_data ad;
	u8 secmark_active;
4353
	u8 netlbl_active;
4354
	u8 peerlbl_active;
4355

4356 4357
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4358

4359
	secmark_active = selinux_secmark_enabled();
4360 4361
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4362 4363
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4364

4365 4366 4367
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4368 4369 4370 4371 4372 4373
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4374 4375 4376 4377 4378
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4379
			return NF_DROP;
4380 4381
		}
	}
4382 4383 4384 4385 4386 4387

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

4388 4389 4390 4391 4392 4393 4394 4395
	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;

4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418
	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 */

4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449
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);
}

4450 4451
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4452
						u16 family)
4453 4454 4455
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4456 4457 4458
	struct avc_audit_data ad;
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4459

4460 4461 4462 4463
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4464 4465 4466 4467 4468 4469
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4470
	if (selinux_secmark_enabled())
4471
		if (avc_has_perm(sksec->sid, skb->secmark,
4472
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4473 4474 4475
			return NF_DROP;

	if (selinux_policycap_netpeer)
4476
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4477 4478 4479
			return NF_DROP;

	return NF_ACCEPT;
4480 4481
}

4482 4483
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4484
{
4485 4486
	u32 secmark_perm;
	u32 peer_sid;
4487 4488
	struct sock *sk;
	struct avc_audit_data ad;
4489 4490 4491
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4492

4493 4494 4495 4496
	/* 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. */
4497
	if (!selinux_policycap_netpeer)
4498
		return selinux_ip_postroute_compat(skb, ifindex, family);
4499
#ifdef CONFIG_XFRM
4500 4501 4502 4503 4504 4505 4506 4507
	/* 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. */
	if (skb->dst != NULL && skb->dst->xfrm != NULL)
		return NF_ACCEPT;
4508
#endif
4509 4510 4511 4512 4513
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4514 4515 4516 4517
	/* 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 */
4518
	sk = skb->sk;
4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541
	if (sk == NULL) {
		switch (family) {
		case PF_INET:
			if (IPCB(skb)->flags & IPSKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		case PF_INET6:
			if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
				secmark_perm = PACKET__FORWARD_OUT;
			else
				secmark_perm = PACKET__SEND;
			break;
		default:
			return NF_DROP;
		}
		if (secmark_perm == PACKET__FORWARD_OUT) {
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
				return NF_DROP;
		} else
			peer_sid = SECINITSID_KERNEL;
	} else {
4542 4543 4544 4545
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4546

4547 4548 4549 4550 4551 4552
	AVC_AUDIT_DATA_INIT(&ad, NET);
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
		return NF_DROP;

4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
			return NF_DROP;

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

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

		if (sel_netnode_sid(addrp, family, &node_sid))
			return NF_DROP;
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
			return NF_DROP;
	}
4574

4575
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4576 4577
}

4578 4579 4580 4581 4582
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
4583
{
4584
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4585 4586 4587
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4588 4589 4590 4591 4592
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
4593
{
4594
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4595 4596 4597 4598 4599 4600 4601 4602 4603
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4604
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4605 4606 4607 4608 4609 4610 4611 4612 4613
	if (err)
		return err;

	if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS)
		err = selinux_nlmsg_perm(sk, skb);

	return err;
}

4614
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4615
{
4616 4617 4618
	int err;
	struct avc_audit_data ad;

4619
	err = cap_netlink_recv(skb, capability);
4620 4621 4622 4623 4624 4625 4626
	if (err)
		return err;

	AVC_AUDIT_DATA_INIT(&ad, CAP);
	ad.u.cap = capability;

	return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid,
4627
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4628 4629 4630 4631 4632 4633 4634
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4635
	u32 sid;
L
Linus Torvalds 已提交
4636

J
James Morris 已提交
4637
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4638 4639 4640
	if (!isec)
		return -ENOMEM;

4641
	sid = task_sid(task);
L
Linus Torvalds 已提交
4642
	isec->sclass = sclass;
4643
	isec->sid = sid;
L
Linus Torvalds 已提交
4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659
	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
4660
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678
	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,
4679
			u32 perms)
L
Linus Torvalds 已提交
4680 4681 4682
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4683
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4684 4685 4686 4687 4688 4689

	isec = ipc_perms->security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = ipc_perms->key;

4690
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706 4707
}

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;
	struct avc_audit_data ad;
4708
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4709 4710 4711 4712 4713 4714 4715 4716 4717
	int rc;

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

	isec = msq->q_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
4718
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4719

4720
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737
			  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;
	struct avc_audit_data ad;
4738
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4739 4740 4741 4742 4743 4744

	isec = msq->q_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = msq->q_perm.key;

4745
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4746 4747 4748 4749 4750 4751 4752 4753
			    MSGQ__ASSOCIATE, &ad);
}

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

4754
	switch (cmd) {
L
Linus Torvalds 已提交
4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772
	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;
	}

4773
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4774 4775 4776 4777 4778 4779 4780 4781
	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;
	struct avc_audit_data ad;
4782
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795
	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
		 */
4796
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
4797 4798 4799 4800 4801 4802 4803 4804 4805
					     &msec->sid);
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4806
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4807 4808 4809
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4810 4811
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4812 4813
	if (!rc)
		/* Can the message be put in the queue? */
4814 4815
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826

	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;
	struct avc_audit_data ad;
4827
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4828 4829 4830 4831 4832 4833
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, IPC);
4834
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4835

4836
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4837 4838
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4839
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4840 4841 4842 4843 4844 4845 4846 4847 4848
				  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;
	struct avc_audit_data ad;
4849
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4850 4851 4852 4853 4854 4855 4856 4857 4858
	int rc;

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

	isec = shp->shm_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
4859
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4860

4861
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878
			  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;
	struct avc_audit_data ad;
4879
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4880 4881 4882 4883 4884 4885

	isec = shp->shm_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = shp->shm_perm.key;

4886
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4887 4888 4889 4890 4891 4892 4893 4894 4895
			    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;

4896
	switch (cmd) {
L
Linus Torvalds 已提交
4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918
	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;
	}

4919
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932
	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;

4933
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
4934 4935 4936 4937 4938 4939 4940
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4941
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4942 4943 4944 4945 4946 4947 4948 4949 4950
	int rc;

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

	isec = sma->sem_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
4951
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
4952

4953
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970
			  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;
	struct avc_audit_data ad;
4971
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4972 4973 4974 4975 4976 4977

	isec = sma->sem_perm.security;

	AVC_AUDIT_DATA_INIT(&ad, IPC);
	ad.u.ipc_id = sma->sem_perm.key;

4978
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
4979 4980 4981 4982 4983 4984 4985 4986 4987
			    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;

4988
	switch (cmd) {
L
Linus Torvalds 已提交
4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019
	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;
	}

5020
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033
	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;

5034
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049
}

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;

5050
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5051 5052
}

5053 5054 5055 5056 5057 5058
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5059
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5060 5061 5062 5063 5064 5065
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5066
			       char *name, char **value)
L
Linus Torvalds 已提交
5067
{
5068
	const struct task_security_struct *__tsec;
5069
	u32 sid;
L
Linus Torvalds 已提交
5070
	int error;
5071
	unsigned len;
L
Linus Torvalds 已提交
5072 5073

	if (current != p) {
5074
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5075 5076 5077 5078
		if (error)
			return error;
	}

5079 5080
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5081 5082

	if (!strcmp(name, "current"))
5083
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5084
	else if (!strcmp(name, "prev"))
5085
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5086
	else if (!strcmp(name, "exec"))
5087
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5088
	else if (!strcmp(name, "fscreate"))
5089
		sid = __tsec->create_sid;
5090
	else if (!strcmp(name, "keycreate"))
5091
		sid = __tsec->keycreate_sid;
5092
	else if (!strcmp(name, "sockcreate"))
5093
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5094
	else
5095 5096
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5097 5098 5099 5100

	if (!sid)
		return 0;

5101 5102 5103 5104
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5105 5106 5107 5108

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5109 5110 5111 5112 5113 5114
}

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
5115
	struct task_struct *tracer;
D
David Howells 已提交
5116 5117
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132
	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"))
5133
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5134
	else if (!strcmp(name, "fscreate"))
5135
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5136
	else if (!strcmp(name, "keycreate"))
5137
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5138
	else if (!strcmp(name, "sockcreate"))
5139
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5140
	else if (!strcmp(name, "current"))
5141
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153
	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);
5154 5155 5156 5157 5158 5159
		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
5160 5161 5162 5163
		if (error)
			return error;
	}

D
David Howells 已提交
5164 5165 5166 5167
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5168 5169 5170
	/* 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
5171
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5172 5173
	   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
5174 5175
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5176
		tsec->exec_sid = sid;
D
David Howells 已提交
5177
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5178
		tsec->create_sid = sid;
D
David Howells 已提交
5179
	} else if (!strcmp(name, "keycreate")) {
5180 5181
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5182
			goto abort_change;
5183
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5184
	} else if (!strcmp(name, "sockcreate")) {
5185
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5186 5187
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5188
		if (sid == 0)
D
David Howells 已提交
5189 5190 5191 5192 5193 5194 5195 5196
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
		if (!is_single_threaded(p)) {
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5197
		}
L
Linus Torvalds 已提交
5198 5199 5200

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5201
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5202
		if (error)
D
David Howells 已提交
5203
			goto abort_change;
L
Linus Torvalds 已提交
5204 5205 5206

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5207
		ptsid = 0;
L
Linus Torvalds 已提交
5208
		task_lock(p);
5209
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5210 5211 5212 5213 5214 5215 5216
		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
5217
			if (error)
D
David Howells 已提交
5218
				goto abort_change;
L
Linus Torvalds 已提交
5219 5220
		}

D
David Howells 已提交
5221 5222 5223 5224 5225 5226 5227
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5228
	return size;
D
David Howells 已提交
5229 5230 5231 5232

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5233 5234
}

5235 5236 5237 5238 5239
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5240
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5241 5242 5243 5244
{
	return security_context_to_sid(secdata, seclen, secid);
}

5245 5246
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5247
	kfree(secdata);
5248 5249
}

5250 5251
#ifdef CONFIG_KEYS

D
David Howells 已提交
5252
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5253
			     unsigned long flags)
5254
{
D
David Howells 已提交
5255
	const struct task_security_struct *tsec;
5256 5257 5258 5259 5260 5261
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5262 5263 5264
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5265
	else
D
David Howells 已提交
5266
		ksec->sid = tsec->sid;
5267

5268
	k->security = ksec;
5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280
	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
5281 5282
				  const struct cred *cred,
				  key_perm_t perm)
5283 5284 5285
{
	struct key *key;
	struct key_security_struct *ksec;
5286
	u32 sid;
5287 5288 5289 5290 5291 5292 5293

	/* 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
5294
	sid = cred_sid(cred);
5295 5296 5297 5298 5299

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5300 5301
}

5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315
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;
}

5316 5317
#endif

L
Linus Torvalds 已提交
5318
static struct security_operations selinux_ops = {
5319 5320
	.name =				"selinux",

5321 5322
	.ptrace_may_access =		selinux_ptrace_may_access,
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5323
	.capget =			selinux_capget,
D
David Howells 已提交
5324
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5325 5326 5327 5328 5329 5330 5331 5332
	.sysctl =			selinux_sysctl,
	.capable =			selinux_capable,
	.quotactl =			selinux_quotactl,
	.quota_on =			selinux_quota_on,
	.syslog =			selinux_syslog,
	.vm_enough_memory =		selinux_vm_enough_memory,

	.netlink_send =			selinux_netlink_send,
5333
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5334

5335 5336 5337
	.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
5338 5339 5340 5341 5342
	.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,
5343
	.sb_kern_mount =		selinux_sb_kern_mount,
5344
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5345 5346 5347
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5348
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5349
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5350 5351
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5352 5353 5354

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5355
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373
	.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,
5374 5375 5376
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5377
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390

	.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,

5391
	.dentry_open =			selinux_dentry_open,
5392

L
Linus Torvalds 已提交
5393
	.task_create =			selinux_task_create,
5394
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5395
	.cred_prepare =			selinux_cred_prepare,
5396 5397
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
L
Linus Torvalds 已提交
5398 5399
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5400
	.task_getsid =			selinux_task_getsid,
5401
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5402
	.task_setnice =			selinux_task_setnice,
5403
	.task_setioprio =		selinux_task_setioprio,
5404
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5405 5406 5407
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5408
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5409 5410
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5411
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5412 5413

	.ipc_permission =		selinux_ipc_permission,
5414
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431

	.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,

5432 5433
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5434 5435 5436 5437
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5438
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5439

5440 5441
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5442

5443
	.secid_to_secctx =		selinux_secid_to_secctx,
5444
	.secctx_to_secid =		selinux_secctx_to_secid,
5445 5446
	.release_secctx =		selinux_release_secctx,

5447
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463
	.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
5464 5465
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5466 5467
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5468
	.sk_clone_security =		selinux_sk_clone_security,
5469
	.sk_getsecid =			selinux_sk_getsecid,
5470 5471 5472
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5473
	.inet_conn_established =	selinux_inet_conn_established,
5474
	.req_classify_flow =		selinux_req_classify_flow,
5475 5476 5477 5478 5479

#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
5480
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5481 5482
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5483
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5484
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5485 5486
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5487
#endif
5488 5489

#ifdef CONFIG_KEYS
5490 5491 5492
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5493
	.key_getsecurity =		selinux_key_getsecurity,
5494
#endif
5495 5496 5497 5498 5499 5500 5501

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
Linus Torvalds 已提交
5502 5503 5504 5505
};

static __init int selinux_init(void)
{
5506 5507 5508 5509 5510
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5511 5512 5513 5514 5515 5516 5517 5518
	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
5519
	cred_init_security();
L
Linus Torvalds 已提交
5520

5521 5522
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5523
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5524 5525
	avc_init();

5526
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5527
	if (!secondary_ops)
5528 5529
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5530 5531
		panic("SELinux: Unable to register with kernel.\n");

5532
	if (selinux_enforcing)
5533
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5534
	else
5535
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5536

L
Linus Torvalds 已提交
5537 5538 5539 5540 5541
	return 0;
}

void selinux_complete_init(void)
{
5542
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5543 5544

	/* Set up any superblocks initialized prior to the policy load. */
5545
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5546
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5547 5548 5549 5550 5551
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5552 5553
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5554 5555 5556
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5557
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5558 5559 5560 5561
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5562
		spin_lock(&sb_lock);
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		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5568
	spin_unlock(&sb_lock);
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}

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

5575
#if defined(CONFIG_NETFILTER)
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5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590
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,
5591 5592 5593 5594 5595 5596 5597
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5598
	}
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};

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

5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617
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,
	}
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};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5628 5629 5630

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

5631 5632 5633
	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);
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5636 5637 5638
	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);
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Linus Torvalds 已提交
5639
#endif	/* IPV6 */
5640

L
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out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5650
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5651

5652
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5653
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5654
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
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#endif	/* IPV6 */
}
#endif

5659
#else /* CONFIG_NETFILTER */
L
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5665
#endif /* CONFIG_NETFILTER */
L
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5668 5669
static int selinux_disabled;

L
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int selinux_disable(void)
{
	extern void exit_sel_fs(void);

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

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

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

	selinux_disabled = 1;
5687
	selinux_enabled = 0;
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	/* Reset security_ops to the secondary module, dummy or capability. */
	security_ops = secondary_ops;

	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif