hooks.c 141.9 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007 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 4

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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 int selinux_compat_net;
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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, family);
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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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};

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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_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->initialized = 1;
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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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	/* 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->initialized)
		return -EINVAL;
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	if (!ss_initialized)
		return -EINVAL;
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	/*
	 * if we ever use sbsec flags for anything other than tracking mount
	 * settings this is going to need a mask
	 */
	tmp = sbsec->flags;
	/* 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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	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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	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)
{
	/* check if the old mount command had the same options */
	if (sbsec->initialized)
		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
	 */
	if (!sbsec->initialized)
		if (sbsec->flags & flag)
			return 1;
	return 0;
}
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/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
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static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
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{
587
	const struct cred *cred = current_cred();
588 589 590
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
591 592
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
593 594
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
595 596 597
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
598 599 600 601 602 603 604 605 606 607 608 609 610 611 612

	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
613 614
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
615
		goto out;
616
	}
L
Linus Torvalds 已提交
617

618 619 620 621 622 623 624 625 626 627 628 629 630
	/*
	 * 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)
	 */
	if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
	    && (num_opts == 0))
631
		goto out;
632

633 634 635 636 637 638 639 640 641
	/*
	 * 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;
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
642 643 644
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
			       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
690
		}
691 692 693 694 695 696 697 698 699 700
	}

	if (sbsec->initialized) {
		/* previously mounted with options, but not on this attempt? */
		if (sbsec->flags && !num_opts)
			goto out_double_mount;
		rc = 0;
		goto out;
	}

701
	if (strcmp(sb->s_type->name, "proc") == 0)
702 703 704
		sbsec->proc = 1;

	/* Determine the labeling behavior to use for this filesystem type. */
705
	rc = security_fs_use(sbsec->proc ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
706 707
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
708
		       __func__, sb->s_type->name, rc);
709 710
		goto out;
	}
L
Linus Torvalds 已提交
711

712 713
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
714
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
715
		if (rc)
716
			goto out;
L
Linus Torvalds 已提交
717

718
		sbsec->sid = fscontext_sid;
719 720 721 722 723 724 725
	}

	/*
	 * 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.
	 */
726 727
	if (context_sid) {
		if (!fscontext_sid) {
728 729
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
730
			if (rc)
731 732
				goto out;
			sbsec->sid = context_sid;
733
		} else {
734 735
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
736
			if (rc)
737
				goto out;
738
		}
739 740
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
741

742
		sbsec->mntpoint_sid = context_sid;
743
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
744 745
	}

746
	if (rootcontext_sid) {
747 748
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
749
		if (rc)
750
			goto out;
751

752 753
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
754 755
	}

756 757 758 759 760 761
	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
762 763
		}

764 765
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
766
							     sbsec, cred);
767 768 769
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
770

771
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
772 773
	}

774
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
775
out:
776
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
777
	return rc;
778 779 780 781 782
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
783 784
}

785 786
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
787
{
788 789
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
790

791 792 793
	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
794

795 796 797 798 799 800 801 802 803 804 805 806
	/*
	 * 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;
	}
807 808 809 810

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

811 812 813 814
	/* if fs is reusing a sb, just let its options stand... */
	if (newsbsec->initialized)
		return;

815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833
	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
834
	}
835 836 837 838 839
	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
840

841
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
842 843
	}

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

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

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

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

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

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

868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924
		switch (token) {
		case Opt_context:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			context = match_strdup(&args[0]);
			if (!context) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_fscontext:
			if (fscontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			fscontext = match_strdup(&args[0]);
			if (!fscontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_rootcontext:
			if (rootcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			rootcontext = match_strdup(&args[0]);
			if (!rootcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_defcontext:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			defcontext = match_strdup(&args[0]);
			if (!defcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
925 926 927

		}
	}
928

929 930 931 932 933 934 935 936 937 938 939
	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;
	}

940
	if (fscontext) {
941 942
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
943 944
	}
	if (context) {
945 946
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
947 948
	}
	if (rootcontext) {
949 950
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
951 952
	}
	if (defcontext) {
953 954
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
955 956
	}

957 958 959
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

960 961 962 963 964
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
965 966
	return rc;
}
967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993
/*
 * 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
994

A
Adrian Bunk 已提交
995 996
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
		char *has_comma = strchr(opts->mnt_opts[i], ',');

		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;
		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);
1037 1038 1039 1040
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1041
		return rc;
1042
	}
1043 1044 1045 1046 1047 1048 1049 1050

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
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;
}

1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
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
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
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:
1100 1101 1102 1103
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1104
		case SOCK_DGRAM:
1105 1106 1107 1108
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1109 1110
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1111
		default:
L
Linus Torvalds 已提交
1112 1113 1114 1115 1116 1117 1118 1119 1120
			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;
1121
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134
			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;
1135 1136
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142 1143
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1144 1145
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158
	}

	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;

1159
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206
	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;

1207
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1208
	if (isec->initialized)
1209
		goto out_unlock;
L
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1210 1211 1212 1213 1214 1215 1216 1217 1218 1219

	sbsec = inode->i_sb->s_security;
	if (!sbsec->initialized) {
		/* 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);
1220
		goto out_unlock;
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1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239
	}

	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) {
E
Eric Paris 已提交
1240
			printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1241
			       "ino=%ld\n", __func__, inode->i_sb->s_id,
L
Linus Torvalds 已提交
1242
			       inode->i_ino);
1243
			goto out_unlock;
L
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1244 1245 1246
		}

		len = INITCONTEXTLEN;
1247
		context = kmalloc(len, GFP_NOFS);
L
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1248 1249 1250
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1251
			goto out_unlock;
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1252 1253 1254 1255 1256 1257 1258 1259 1260
		}
		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);
1261
				goto out_unlock;
L
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1262 1263 1264
			}
			kfree(context);
			len = rc;
1265
			context = kmalloc(len, GFP_NOFS);
L
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1266 1267 1268
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1269
				goto out_unlock;
L
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1270 1271 1272 1273 1274 1275 1276 1277
			}
			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
1278
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1279
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1280 1281
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1282
				goto out_unlock;
L
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1283 1284 1285 1286 1287
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1288
			rc = security_context_to_sid_default(context, rc, &sid,
1289 1290
							     sbsec->def_sid,
							     GFP_NOFS);
L
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1291
			if (rc) {
E
Eric Paris 已提交
1292
				printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
L
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1293
				       "returned %d for dev=%s ino=%ld\n",
1294
				       __func__, context, -rc,
L
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1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
				       inode->i_sb->s_id, inode->i_ino);
				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)
1319
			goto out_unlock;
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1320 1321
		isec->sid = sid;
		break;
1322 1323 1324
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
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1325
	default:
1326
		/* Default to the fs superblock SID. */
L
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1327 1328
		isec->sid = sbsec->sid;

1329
		if (sbsec->proc && !S_ISLNK(inode->i_mode)) {
L
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1330 1331 1332 1333 1334 1335 1336
			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)
1337
					goto out_unlock;
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1338 1339 1340 1341 1342 1343 1344 1345
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1346 1347
out_unlock:
	mutex_unlock(&isec->lock);
L
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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
1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393
/*
 * 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);
}

1394
/*
1395
 * Check permission between a pair of tasks, e.g. signal checks,
1396 1397
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1398
 * - this uses the default subjective creds of tsk1
1399 1400 1401
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1402 1403
			 u32 perms)
{
1404 1405
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1406

1407 1408 1409 1410 1411
	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
1412 1413
}

1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429
/*
 * 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);
}

1430 1431 1432 1433
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
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1434 1435
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1436
			       const struct cred *cred,
1437
			       int cap, int audit)
L
Linus Torvalds 已提交
1438 1439
{
	struct avc_audit_data ad;
1440
	struct av_decision avd;
1441
	u16 sclass;
1442
	u32 sid = cred_sid(cred);
1443
	u32 av = CAP_TO_MASK(cap);
1444
	int rc;
L
Linus Torvalds 已提交
1445

1446
	AVC_AUDIT_DATA_INIT(&ad, CAP);
L
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1447 1448 1449
	ad.tsk = tsk;
	ad.u.cap = cap;

1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461
	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();
	}
1462

1463
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1464
	if (audit == SECURITY_CAP_AUDIT)
1465
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1466
	return rc;
L
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1467 1468 1469 1470 1471 1472
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1473
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1474

1475
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1476 1477 1478 1479 1480 1481
			    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). */
1482
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1483 1484 1485 1486 1487 1488
			  struct inode *inode,
			  u32 perms,
			  struct avc_audit_data *adp)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
1489
	u32 sid;
L
Linus Torvalds 已提交
1490

1491
	if (unlikely(IS_PRIVATE(inode)))
1492 1493
		return 0;

1494
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1495 1496 1497 1498 1499 1500 1501 1502
	isec = inode->i_security;

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

1503
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
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1504 1505 1506 1507 1508
}

/* 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. */
1509
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1510 1511 1512 1513 1514 1515
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
	struct avc_audit_data ad;
1516

1517
	AVC_AUDIT_DATA_INIT(&ad, FS);
1518 1519
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1520
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1521 1522 1523 1524 1525 1526 1527 1528 1529 1530
}

/* 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. */
1531 1532 1533
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1534 1535
{
	struct file_security_struct *fsec = file->f_security;
1536
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1537
	struct avc_audit_data ad;
1538
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1539 1540 1541
	int rc;

	AVC_AUDIT_DATA_INIT(&ad, FS);
1542
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1543

1544 1545
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1546 1547 1548 1549
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1550
			goto out;
L
Linus Torvalds 已提交
1551 1552 1553
	}

	/* av is zero if only checking access to the descriptor. */
1554
	rc = 0;
L
Linus Torvalds 已提交
1555
	if (av)
1556
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1557

1558 1559
out:
	return rc;
L
Linus Torvalds 已提交
1560 1561 1562 1563 1564 1565 1566
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1567 1568
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1569 1570
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1571
	u32 sid, newsid;
L
Linus Torvalds 已提交
1572 1573 1574 1575 1576 1577
	struct avc_audit_data ad;
	int rc;

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

1578 1579 1580
	sid = tsec->sid;
	newsid = tsec->create_sid;

L
Linus Torvalds 已提交
1581
	AVC_AUDIT_DATA_INIT(&ad, FS);
1582
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1583

1584
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1585 1586 1587 1588 1589
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1590 1591
	if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
		rc = security_transition_sid(sid, dsec->sid, tclass, &newsid);
L
Linus Torvalds 已提交
1592 1593 1594 1595
		if (rc)
			return rc;
	}

1596
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1597 1598 1599 1600 1601 1602 1603 1604
	if (rc)
		return rc;

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

1605 1606 1607 1608
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1609
	u32 sid = task_sid(ctx);
1610

1611
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1612 1613
}

1614 1615 1616
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1617 1618 1619 1620 1621 1622 1623 1624 1625

/* 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;
1626
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1627 1628 1629 1630 1631 1632 1633
	u32 av;
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, FS);
1634
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1635 1636 1637

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1638
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652
	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
1653 1654
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1655 1656 1657
		return 0;
	}

1658
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1659 1660 1661 1662 1663 1664 1665 1666 1667 1668
	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;
1669
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680
	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);

1681
	ad.u.fs.path.dentry = old_dentry;
1682
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1683 1684 1685
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1686
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1687 1688 1689 1690
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1691
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1692 1693 1694 1695 1696
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1697
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1698 1699 1700
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1701
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1702 1703 1704 1705 1706
	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);
1707
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1708 1709 1710 1711 1712 1713 1714 1715 1716 1717
				  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. */
1718
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1719 1720 1721 1722 1723
			       struct super_block *sb,
			       u32 perms,
			       struct avc_audit_data *ad)
{
	struct superblock_security_struct *sbsec;
1724
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1725 1726

	sbsec = sb->s_security;
1727
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757
}

/* 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;
}

1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780
/* 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
1781
/*
1782
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1783 1784
 * open permission.
 */
1785
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1786
{
1787
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1788 1789

	if (selinux_policycap_openperm) {
1790
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804
		/*
		 * 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;
		else
E
Eric Paris 已提交
1805
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1806
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1807 1808 1809 1810
	}
	return av;
}

L
Linus Torvalds 已提交
1811 1812
/* Hook functions begin here. */

1813 1814
static int selinux_ptrace_may_access(struct task_struct *child,
				     unsigned int mode)
L
Linus Torvalds 已提交
1815 1816 1817
{
	int rc;

1818
	rc = secondary_ops->ptrace_may_access(child, mode);
L
Linus Torvalds 已提交
1819 1820 1821
	if (rc)
		return rc;

1822
	if (mode == PTRACE_MODE_READ) {
1823 1824 1825
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1826 1827
	}

1828
	return current_has_perm(child, PROCESS__PTRACE);
1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839
}

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

	rc = secondary_ops->ptrace_traceme(parent);
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1840 1841 1842
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1843
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1844 1845 1846
{
	int error;

1847
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1848 1849 1850 1851 1852 1853
	if (error)
		return error;

	return secondary_ops->capget(target, effective, inheritable, permitted);
}

D
David Howells 已提交
1854 1855 1856 1857
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
1858 1859 1860
{
	int error;

D
David Howells 已提交
1861 1862
	error = secondary_ops->capset(new, old,
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1863 1864 1865
	if (error)
		return error;

D
David Howells 已提交
1866
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1867 1868
}

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

1874
	rc = secondary_ops->capable(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1875 1876 1877
	if (rc)
		return rc;

1878
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1879 1880
}

1881 1882 1883 1884 1885 1886
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1887
	buffer = (char *)__get_free_page(GFP_KERNEL);
1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908
	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;
	}
1909 1910 1911 1912 1913 1914
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1915 1916 1917 1918 1919 1920 1921
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1922 1923 1924 1925
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1926
	u32 tsid, sid;
L
Linus Torvalds 已提交
1927 1928 1929 1930 1931 1932
	int rc;

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

1933
	sid = current_sid();
L
Linus Torvalds 已提交
1934

1935 1936
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1937 1938 1939 1940 1941 1942 1943
	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 */
1944
	if (op == 001) {
1945
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1946 1947 1948 1949 1950 1951 1952 1953
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
1954
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1955
					     SECCLASS_FILE, av, NULL);
1956
	}
L
Linus Torvalds 已提交
1957 1958 1959 1960 1961 1962

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1963
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1964 1965 1966 1967 1968 1969
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1970 1971 1972 1973 1974
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1975
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1976 1977 1978 1979
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1980
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1981 1982 1983 1984
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1985 1986 1987 1988 1989 1990
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1991 1992 1993
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
}

static int selinux_syslog(int type)
{
	int rc;

	rc = secondary_ops->syslog(type);
	if (rc)
		return rc;

	switch (type) {
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
	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
2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037
	}
	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.
 *
 * Note that secondary_ops->capable and task_has_perm_noaudit return 0
 * if the capability is granted, but __vm_enough_memory requires 1 if
 * the capability is granted.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
2038
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2039 2040 2041
{
	int rc, cap_sys_admin = 0;

2042 2043
	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2044 2045 2046
	if (rc == 0)
		cap_sys_admin = 1;

2047
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2048 2049 2050 2051
}

/* binprm security operations */

2052
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2053
{
2054 2055
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2056 2057
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
2058
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2059 2060
	int rc;

2061
	rc = secondary_ops->bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2062 2063 2064
	if (rc)
		return rc;

2065 2066 2067
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2068 2069
		return 0;

2070 2071
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2072 2073 2074
	isec = inode->i_security;

	/* Default to the current task SID. */
2075 2076
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2077

2078
	/* Reset fs, key, and sock SIDs on execve. */
2079 2080 2081
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2082

2083 2084
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2085
		/* Reset exec SID on execve. */
2086
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2087 2088
	} else {
		/* Check for a default transition on this program. */
2089 2090
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2091 2092 2093 2094 2095
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, FS);
2096
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2097

J
Josef Sipek 已提交
2098
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2099
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2100

2101 2102
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2103 2104 2105 2106 2107
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2108
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2109 2110 2111 2112
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2113
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2114 2115 2116 2117
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150
		/* 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
2151

2152 2153
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2154 2155 2156 2157 2158
	}

	return 0;
}

2159
static int selinux_bprm_check_security(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2160 2161 2162 2163
{
	return secondary_ops->bprm_check_security(bprm);
}

2164
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2165
{
2166 2167 2168
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2169 2170
	int atsecure = 0;

2171 2172 2173 2174
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2175 2176 2177
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2178
		atsecure = avc_has_perm(osid, sid,
2179 2180
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2181 2182 2183 2184 2185 2186 2187 2188 2189
	}

	return (atsecure || secondary_ops->bprm_secureexec(bprm));
}

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

/* Derived from fs/exec.c:flush_old_files. */
2190 2191
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2192 2193 2194
{
	struct avc_audit_data ad;
	struct file *file, *devnull = NULL;
2195
	struct tty_struct *tty;
2196
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2197
	long j = -1;
2198
	int drop_tty = 0;
L
Linus Torvalds 已提交
2199

2200
	tty = get_current_tty();
L
Linus Torvalds 已提交
2201 2202
	if (tty) {
		file_list_lock();
2203 2204 2205
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2206 2207 2208 2209 2210
			/* 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. */
2211 2212
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2213
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2214
					   FILE__READ | FILE__WRITE, NULL)) {
2215
				drop_tty = 1;
L
Linus Torvalds 已提交
2216 2217 2218
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2219
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2220
	}
2221 2222 2223
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2224 2225 2226

	/* Revalidate access to inherited open files. */

2227
	AVC_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2228 2229 2230 2231 2232 2233 2234 2235

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

		j++;
		i = j * __NFDBITS;
2236
		fdt = files_fdtable(files);
2237
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2238
			break;
2239
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2240 2241 2242
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2243
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2244 2245 2246 2247
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2248
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259
						  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) {
2260
						get_file(devnull);
L
Linus Torvalds 已提交
2261
					} else {
2262 2263 2264 2265
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2266 2267
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2284 2285 2286 2287
/*
 * 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
2288
{
2289 2290 2291
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2292

2293
	secondary_ops->bprm_committing_creds(bprm);
L
Linus Torvalds 已提交
2294

2295 2296 2297
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2298

2299 2300
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2301

2302 2303
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2304

2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321
	/* 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
2322
		}
2323
		update_rlimit_cpu(rlim->rlim_cur);
L
Linus Torvalds 已提交
2324 2325 2326 2327
	}
}

/*
2328 2329
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2330
 */
2331
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2332
{
2333
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2334
	struct itimerval itimer;
2335
	struct sighand_struct *psig;
2336
	u32 osid, sid;
L
Linus Torvalds 已提交
2337
	int rc, i;
2338
	unsigned long flags;
L
Linus Torvalds 已提交
2339

2340
	secondary_ops->bprm_committed_creds(bprm);
L
Linus Torvalds 已提交
2341

2342 2343 2344 2345
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2346 2347
		return;

2348 2349 2350 2351 2352 2353 2354 2355
	/* 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
2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367
	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);
	}

2368 2369
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2370 2371 2372
	read_lock_irq(&tasklist_lock);
	psig = current->parent->sighand;
	spin_lock_irqsave(&psig->siglock, flags);
L
Linus Torvalds 已提交
2373
	wake_up_interruptible(&current->parent->signal->wait_chldexit);
2374 2375
	spin_unlock_irqrestore(&psig->siglock, flags);
	read_unlock_irq(&tasklist_lock);
L
Linus Torvalds 已提交
2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399
}

/* 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)
{
2400 2401 2402 2403
	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) ||
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len));
L
Linus Torvalds 已提交
2404 2405 2406 2407 2408 2409 2410
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2411
	} else
L
Linus Torvalds 已提交
2412 2413 2414 2415 2416
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2417 2418
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2419 2420 2421 2422 2423 2424
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2425
	} else
2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437
		*first = 0;

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

2438
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2439 2440 2441 2442
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2443
	int open_quote = 0;
L
Linus Torvalds 已提交
2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458

	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 {
2459 2460 2461 2462
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2463 2464 2465
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2466
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2467 2468 2469 2470 2471 2472 2473
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2474
	strcpy(in_save, nosec_save);
2475
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2476 2477 2478 2479
out:
	return rc;
}

2480
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2481
{
2482
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2483 2484 2485 2486 2487 2488 2489
	struct avc_audit_data ad;
	int rc;

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

2490 2491 2492 2493
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2494
	AVC_AUDIT_DATA_INIT(&ad, FS);
2495
	ad.u.fs.path.dentry = sb->s_root;
2496
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2497 2498
}

2499
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2500
{
2501
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2502 2503
	struct avc_audit_data ad;

2504
	AVC_AUDIT_DATA_INIT(&ad, FS);
2505
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2506
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2507 2508
}

2509
static int selinux_mount(char *dev_name,
2510
			 struct path *path,
2511 2512 2513
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2514
{
2515
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2516 2517
	int rc;

2518
	rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
L
Linus Torvalds 已提交
2519 2520 2521 2522
	if (rc)
		return rc;

	if (flags & MS_REMOUNT)
2523
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2524
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2525
	else
2526
		return dentry_has_perm(cred, path->mnt, path->dentry,
2527
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2528 2529 2530 2531
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2532
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2533 2534 2535 2536 2537 2538
	int rc;

	rc = secondary_ops->sb_umount(mnt, flags);
	if (rc)
		return rc;

2539
	return superblock_has_perm(cred, mnt->mnt_sb,
2540
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554
}

/* 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);
}

2555 2556 2557 2558
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2559 2560
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2561 2562
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2563
	u32 sid, newsid, clen;
2564
	int rc;
2565
	char *namep = NULL, *context;
2566 2567 2568 2569

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

2570 2571 2572 2573 2574
	sid = tsec->sid;
	newsid = tsec->create_sid;

	if (!newsid || sbsec->behavior == SECURITY_FS_USE_MNTPOINT) {
		rc = security_transition_sid(sid, dsec->sid,
2575 2576 2577 2578 2579 2580
					     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",
2581
			       __func__,
2582 2583 2584 2585 2586
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2587 2588 2589 2590 2591 2592 2593
	/* Possibly defer initialization to selinux_complete_init. */
	if (sbsec->initialized) {
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2594

2595
	if (!ss_initialized || sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
2596 2597
		return -EOPNOTSUPP;

2598
	if (name) {
2599
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2600 2601 2602 2603
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2604

2605
	if (value && len) {
2606
		rc = security_sid_to_context_force(newsid, &context, &clen);
2607 2608 2609 2610 2611 2612
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2613 2614 2615 2616 2617
	}

	return 0;
}

L
Linus Torvalds 已提交
2618 2619 2620 2621 2622 2623 2624 2625 2626
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)
{
	int rc;

2627
	rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
L
Linus Torvalds 已提交
2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669
	if (rc)
		return rc;
	return may_link(dir, old_dentry, MAY_LINK);
}

static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
{
	int rc;

	rc = secondary_ops->inode_unlink(dir, dentry);
	if (rc)
		return rc;
	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)
{
	int rc;

	rc = secondary_ops->inode_mknod(dir, dentry, mode, dev);
	if (rc)
		return rc;

	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2670
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2671 2672 2673 2674 2675 2676
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2677 2678 2679
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2680 2681 2682 2683
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2684
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2685 2686
	int rc;

2687
	rc = secondary_ops->inode_follow_link(dentry, nameidata);
L
Linus Torvalds 已提交
2688 2689
	if (rc)
		return rc;
2690
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2691 2692
}

2693
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2694
{
2695
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2696 2697
	int rc;

2698
	rc = secondary_ops->inode_permission(inode, mask);
L
Linus Torvalds 已提交
2699 2700 2701 2702 2703 2704 2705 2706
	if (rc)
		return rc;

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

2707
	return inode_has_perm(cred, inode,
2708
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2709 2710 2711 2712
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2713
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724
	int rc;

	rc = secondary_ops->inode_setattr(dentry, iattr);
	if (rc)
		return rc;

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

	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			       ATTR_ATIME_SET | ATTR_MTIME_SET))
2725
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2726

2727
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2728 2729 2730 2731
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2732 2733 2734
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2735 2736
}

2737
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2738
{
2739 2740
	const struct cred *cred = current_cred();

2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754
	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. */
2755
	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2756 2757
}

2758 2759
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
2760 2761 2762 2763 2764
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
	struct avc_audit_data ad;
2765
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2766 2767
	int rc = 0;

2768 2769
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2770 2771 2772 2773 2774

	sbsec = inode->i_sb->s_security;
	if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
		return -EOPNOTSUPP;

2775
	if (!is_owner_or_cap(inode))
L
Linus Torvalds 已提交
2776 2777
		return -EPERM;

2778
	AVC_AUDIT_DATA_INIT(&ad, FS);
2779
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2780

2781
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2782 2783 2784 2785 2786
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2787 2788 2789 2790 2791
	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
2792 2793 2794
	if (rc)
		return rc;

2795
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2796 2797 2798 2799
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2800
	rc = security_validate_transition(isec->sid, newsid, sid,
2801
					  isec->sclass);
L
Linus Torvalds 已提交
2802 2803 2804 2805 2806 2807 2808 2809 2810 2811
	if (rc)
		return rc;

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

2812
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2813
					const void *value, size_t size,
2814
					int flags)
L
Linus Torvalds 已提交
2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825
{
	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;
	}

2826
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2827
	if (rc) {
2828 2829 2830
		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
2831 2832 2833 2834 2835 2836 2837
		return;
	}

	isec->sid = newsid;
	return;
}

2838
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2839
{
2840 2841 2842
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2843 2844
}

2845
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2846
{
2847 2848 2849
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2850 2851
}

2852
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2853
{
2854 2855
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2856 2857 2858 2859 2860 2861

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

2862
/*
2863
 * Copy the inode security context value to the user.
2864 2865 2866
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2867
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2868
{
2869 2870 2871
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2872
	struct inode_security_struct *isec = inode->i_security;
2873

2874 2875
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2876

2877 2878 2879 2880 2881 2882 2883 2884 2885
	/*
	 * 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.
	 */
2886 2887
	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
				SECURITY_CAP_NOAUDIT);
2888 2889 2890 2891 2892
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2893 2894 2895 2896 2897 2898 2899 2900 2901 2902
	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
2903 2904 2905
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2906
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917
{
	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;

2918
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933
	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;
}

2934 2935 2936 2937 2938 2939 2940 2941 2942 2943
static int selinux_inode_need_killpriv(struct dentry *dentry)
{
	return secondary_ops->inode_need_killpriv(dentry);
}

static int selinux_inode_killpriv(struct dentry *dentry)
{
	return secondary_ops->inode_killpriv(dentry);
}

2944 2945 2946 2947 2948 2949
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
2950 2951
/* file security operations */

2952
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2953
{
2954
	const struct cred *cred = current_cred();
V
Venkat Yekkirala 已提交
2955
	int rc;
J
Josef Sipek 已提交
2956
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2957 2958 2959 2960 2961 2962 2963 2964 2965 2966

	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;

2967
	rc = file_has_perm(cred, file,
V
Venkat Yekkirala 已提交
2968 2969 2970 2971 2972
			   file_mask_to_av(inode->i_mode, mask));
	if (rc)
		return rc;

	return selinux_netlbl_inode_permission(inode, mask);
L
Linus Torvalds 已提交
2973 2974
}

2975 2976 2977 2978 2979
static int selinux_file_permission(struct file *file, int mask)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
2980
	u32 sid = current_sid();
2981 2982 2983 2984 2985 2986

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

2987
	if (sid == fsec->sid && fsec->isid == isec->sid
2988 2989 2990 2991 2992 2993
	    && fsec->pseqno == avc_policy_seqno())
		return selinux_netlbl_inode_permission(inode, mask);

	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006
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)
{
3007
	const struct cred *cred = current_cred();
3008
	u32 av = 0;
L
Linus Torvalds 已提交
3009

3010 3011 3012 3013 3014 3015
	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
3016

3017
	return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3018 3019 3020 3021
}

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3022
	const struct cred *cred = current_cred();
D
David Howells 已提交
3023
	int rc = 0;
3024

L
Linus Torvalds 已提交
3025 3026 3027 3028 3029 3030 3031
#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
3032
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3033
		if (rc)
D
David Howells 已提交
3034
			goto error;
L
Linus Torvalds 已提交
3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048
	}
#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;

3049
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3050
	}
D
David Howells 已提交
3051 3052 3053

error:
	return rc;
L
Linus Torvalds 已提交
3054 3055 3056
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3057 3058
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3059
{
3060
	int rc = 0;
3061
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3062

3063 3064 3065 3066
	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
3067 3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079
		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)
{
3080
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3081 3082 3083 3084 3085 3086 3087 3088 3089 3090
	int rc;

	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
	if (rc)
		return rc;

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3091 3092 3093 3094
	if ((prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
		rc = 0;
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3095
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3096 3097 3098
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3099
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3100 3101 3102 3103 3104 3105 3106 3107
		} 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
3108
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3109
		}
3110 3111 3112
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3113 3114 3115 3116 3117 3118 3119
#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)
{
3120 3121 3122
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3123 3124 3125 3126 3127
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3128
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3129 3130 3131
	int err = 0;

	switch (cmd) {
3132 3133 3134 3135 3136
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3137

3138
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3139
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3140
			break;
3141 3142 3143 3144 3145 3146 3147 3148
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3149
		err = file_has_perm(cred, file, 0);
3150 3151 3152 3153
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3154
#if BITS_PER_LONG == 32
3155 3156 3157
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3158
#endif
3159 3160
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3161
			break;
3162
		}
3163
		err = file_has_perm(cred, file, FILE__LOCK);
3164
		break;
L
Linus Torvalds 已提交
3165 3166 3167 3168 3169 3170 3171 3172 3173 3174
	}

	return err;
}

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

	fsec = file->f_security;
3175
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3176 3177 3178 3179 3180 3181 3182

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3183
	struct file *file;
3184
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3185 3186 3187 3188
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3189
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3190 3191 3192 3193 3194 3195 3196 3197

	fsec = file->f_security;

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

3198
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3199 3200 3201 3202 3203
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3204 3205 3206
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3207 3208
}

3209
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3210 3211 3212 3213
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3214

3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234
	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.
	 */
3235
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3236 3237
}

L
Linus Torvalds 已提交
3238 3239 3240 3241 3242 3243 3244 3245 3246 3247
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
	int rc;

	rc = secondary_ops->task_create(clone_flags);
	if (rc)
		return rc;

3248
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3249 3250
}

D
David Howells 已提交
3251 3252 3253 3254
/*
 * 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
3255
{
D
David Howells 已提交
3256 3257 3258 3259
	struct task_security_struct *tsec = cred->security;
	cred->security = NULL;
	kfree(tsec);
}
L
Linus Torvalds 已提交
3260

D
David Howells 已提交
3261 3262 3263 3264 3265 3266 3267 3268
/*
 * 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
3269

D
David Howells 已提交
3270
	old_tsec = old->security;
L
Linus Torvalds 已提交
3271

D
David Howells 已提交
3272 3273 3274
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3275

D
David Howells 已提交
3276
	new->security = tsec;
L
Linus Torvalds 已提交
3277 3278 3279
	return 0;
}

3280
/*
D
David Howells 已提交
3281
 * commit new credentials
3282
 */
D
David Howells 已提交
3283
static void selinux_cred_commit(struct cred *new, const struct cred *old)
L
Linus Torvalds 已提交
3284
{
D
David Howells 已提交
3285
	secondary_ops->cred_commit(new, old);
L
Linus Torvalds 已提交
3286 3287
}

3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331
/*
 * 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
3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342
static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
{
	/* 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. */
	return 0;
}

D
David Howells 已提交
3343 3344
static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
				   int flags)
L
Linus Torvalds 已提交
3345
{
D
David Howells 已提交
3346
	return secondary_ops->task_fix_setuid(new, old, flags);
L
Linus Torvalds 已提交
3347 3348 3349 3350 3351 3352 3353 3354 3355 3356
}

static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
{
	/* See the comment for setuid above. */
	return 0;
}

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

static int selinux_task_getpgid(struct task_struct *p)
{
3362
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3363 3364 3365 3366
}

static int selinux_task_getsid(struct task_struct *p)
{
3367
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3368 3369
}

3370 3371
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3372
	*secid = task_sid(p);
3373 3374
}

L
Linus Torvalds 已提交
3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388
static int selinux_task_setgroups(struct group_info *group_info)
{
	/* See the comment for setuid above. */
	return 0;
}

static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

	rc = secondary_ops->task_setnice(p, nice);
	if (rc)
		return rc;

3389
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3390 3391
}

3392 3393
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3394 3395 3396 3397 3398 3399
	int rc;

	rc = secondary_ops->task_setioprio(p, ioprio);
	if (rc)
		return rc;

3400
	return current_has_perm(p, PROCESS__SETSCHED);
3401 3402
}

3403 3404
static int selinux_task_getioprio(struct task_struct *p)
{
3405
	return current_has_perm(p, PROCESS__GETSCHED);
3406 3407
}

L
Linus Torvalds 已提交
3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419
static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim)
{
	struct rlimit *old_rlim = current->signal->rlim + resource;
	int rc;

	rc = secondary_ops->task_setrlimit(resource, new_rlim);
	if (rc)
		return rc;

	/* 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
3420
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3421
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3422
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3423 3424 3425 3426 3427 3428

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3429 3430 3431 3432 3433 3434
	int rc;

	rc = secondary_ops->task_setscheduler(p, policy, lp);
	if (rc)
		return rc;

3435
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3436 3437 3438 3439
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3440
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3441 3442
}

3443 3444
static int selinux_task_movememory(struct task_struct *p)
{
3445
	return current_has_perm(p, PROCESS__SETSCHED);
3446 3447
}

3448 3449
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3450 3451 3452 3453
{
	u32 perm;
	int rc;

3454
	rc = secondary_ops->task_kill(p, info, sig, secid);
L
Linus Torvalds 已提交
3455 3456 3457 3458 3459 3460 3461
	if (rc)
		return rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3462
	if (secid)
3463 3464
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3465
	else
3466
		rc = current_has_perm(p, perm);
3467
	return rc;
L
Linus Torvalds 已提交
3468 3469 3470 3471 3472 3473
}

static int selinux_task_prctl(int option,
			      unsigned long arg2,
			      unsigned long arg3,
			      unsigned long arg4,
D
David Howells 已提交
3474
			      unsigned long arg5)
L
Linus Torvalds 已提交
3475 3476 3477 3478
{
	/* The current prctl operations do not appear to require
	   any SELinux controls since they merely observe or modify
	   the state of the current process. */
D
David Howells 已提交
3479
	return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
L
Linus Torvalds 已提交
3480 3481 3482 3483
}

static int selinux_task_wait(struct task_struct *p)
{
3484
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3485 3486 3487 3488 3489 3490
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3491
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3492

3493
	isec->sid = sid;
L
Linus Torvalds 已提交
3494 3495 3496 3497
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3498 3499
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3500 3501 3502 3503
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3504
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516
	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;

3517 3518 3519
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3520
	switch (ih->protocol) {
3521 3522
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3523

3524 3525
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3526 3527 3528 3529 3530 3531 3532 3533 3534

		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;
3535 3536 3537 3538 3539 3540 3541 3542
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3543
		offset += ihlen;
3544
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3545
		if (uh == NULL)
3546
			break;
L
Linus Torvalds 已提交
3547

3548 3549 3550 3551
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3552

J
James Morris 已提交
3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566
	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;
3567
	}
J
James Morris 已提交
3568

3569 3570 3571
	default:
		break;
	}
L
Linus Torvalds 已提交
3572 3573 3574 3575 3576 3577 3578
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3579 3580
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3581 3582 3583 3584 3585
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3586
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3587 3588 3589 3590 3591 3592 3593 3594 3595 3596
	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);
3597
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3598 3599 3600
	if (offset < 0)
		goto out;

3601 3602 3603
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3604 3605
	switch (nexthdr) {
	case IPPROTO_TCP: {
3606
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628

		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
3629 3630 3631 3632 3633 3634 3635 3636 3637 3638
	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;
3639
	}
J
James Morris 已提交
3640

L
Linus Torvalds 已提交
3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3652
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3653
{
3654 3655
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3656 3657 3658

	switch (ad->u.net.family) {
	case PF_INET:
3659
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3660 3661 3662 3663 3664
		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
3665 3666 3667

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3668
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3669 3670 3671 3672 3673
		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
3674 3675
#endif	/* IPV6 */
	default:
3676 3677
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3678 3679
	}

3680 3681 3682 3683
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3684
	return ret;
3685 3686 3687 3688 3689

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3690 3691
}

3692
/**
3693
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3694
 * @skb: the packet
3695
 * @family: protocol family
3696
 * @sid: the packet's peer label SID
3697 3698
 *
 * Description:
3699 3700 3701 3702 3703 3704
 * 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.
3705 3706
 *
 */
3707
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3708
{
3709
	int err;
3710 3711
	u32 xfrm_sid;
	u32 nlbl_sid;
3712
	u32 nlbl_type;
3713 3714

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3715
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3716

3717 3718 3719 3720 3721
	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");
3722
		return -EACCES;
3723
	}
3724 3725

	return 0;
3726 3727
}

L
Linus Torvalds 已提交
3728 3729 3730 3731 3732 3733
/* 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;
3734
	u32 sid;
L
Linus Torvalds 已提交
3735 3736 3737 3738 3739 3740
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3741
	sid = task_sid(task);
L
Linus Torvalds 已提交
3742

3743
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3744
	ad.u.net.sk = sock->sk;
3745
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3746 3747 3748 3749 3750 3751 3752 3753

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3754 3755 3756 3757
	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
3758 3759 3760 3761 3762
	int err = 0;

	if (kern)
		goto out;

3763 3764 3765 3766 3767
	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
3768 3769 3770 3771 3772

out:
	return err;
}

V
Venkat Yekkirala 已提交
3773 3774
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3775
{
3776 3777
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3778
	struct inode_security_struct *isec;
3779
	struct sk_security_struct *sksec;
3780 3781 3782 3783 3784
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3785 3786 3787

	isec = SOCK_INODE(sock)->i_security;

3788 3789 3790 3791 3792 3793 3794
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3795 3796 3797
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3798 3799 3800
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3801
		sksec->sclass = isec->sclass;
P
Paul Moore 已提交
3802
		err = selinux_netlbl_socket_post_create(sock);
3803 3804
	}

V
Venkat Yekkirala 已提交
3805
	return err;
L
Linus Torvalds 已提交
3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822
}

/* 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.
3823 3824
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3825 3826 3827 3828 3829 3830 3831 3832 3833 3834
	 */
	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;
3835
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848

		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;
		}

3849 3850 3851 3852 3853 3854
		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
3855 3856
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3857 3858
				if (err)
					goto out;
3859
				AVC_AUDIT_DATA_INIT(&ad, NET);
3860 3861 3862 3863 3864 3865 3866 3867
				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
3868
		}
3869 3870

		switch (isec->sclass) {
3871
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3872 3873
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3874

3875
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3876 3877
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3878 3879 3880 3881 3882

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3883 3884 3885 3886
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3887

3888
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3889 3890
		if (err)
			goto out;
3891 3892

		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3893 3894 3895 3896 3897 3898 3899 3900 3901
		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,
3902
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3903 3904 3905 3906 3907 3908 3909 3910 3911
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3912
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3913 3914 3915 3916 3917 3918 3919 3920
	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
3921
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3922 3923
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3924 3925
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
L
Linus Torvalds 已提交
3926 3927 3928 3929
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3930
		u32 sid, perm;
L
Linus Torvalds 已提交
3931 3932 3933

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3934
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3935 3936 3937 3938
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3939
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3940 3941 3942 3943
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3944
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3945 3946 3947
		if (err)
			goto out;

J
James Morris 已提交
3948 3949 3950
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3951
		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3952 3953
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3954
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3955 3956 3957 3958
		if (err)
			goto out;
	}

3959 3960
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990
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,
3991
				  int size)
L
Linus Torvalds 已提交
3992
{
V
Venkat Yekkirala 已提交
3993 3994 3995 3996 3997 3998 3999
	int rc;

	rc = socket_has_perm(current, sock, SOCKET__WRITE);
	if (rc)
		return rc;

	return selinux_netlbl_inode_permission(SOCK_INODE(sock), MAY_WRITE);
L
Linus Torvalds 已提交
4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017
}

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);
}

4018
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4019
{
4020 4021 4022 4023 4024 4025 4026
	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
4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056
}

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;

	err = secondary_ops->unix_stream_connect(sock, other, newsk);
	if (err)
		return err;

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

4057
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068
	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;
4069

L
Linus Torvalds 已提交
4070 4071 4072
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
4073 4074 4075
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088
}

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;

4089
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4090 4091 4092 4093 4094 4095 4096 4097 4098 4099
	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;
}

4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122
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);
}

4123 4124 4125 4126 4127
static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
						struct sk_buff *skb,
						struct avc_audit_data *ad,
						u16 family,
						char *addrp)
L
Linus Torvalds 已提交
4128
{
4129 4130 4131 4132 4133
	int err;
	struct sk_security_struct *sksec = sk->sk_security;
	u16 sk_class;
	u32 netif_perm, node_perm, recv_perm;
	u32 port_sid, node_sid, if_sid, sk_sid;
L
Linus Torvalds 已提交
4134

4135 4136
	sk_sid = sksec->sid;
	sk_class = sksec->sclass;
L
Linus Torvalds 已提交
4137

4138
	switch (sk_class) {
L
Linus Torvalds 已提交
4139 4140 4141 4142 4143 4144 4145 4146 4147 4148
	case SECCLASS_UDP_SOCKET:
		netif_perm = NETIF__UDP_RECV;
		node_perm = NODE__UDP_RECV;
		recv_perm = UDP_SOCKET__RECV_MSG;
		break;
	case SECCLASS_TCP_SOCKET:
		netif_perm = NETIF__TCP_RECV;
		node_perm = NODE__TCP_RECV;
		recv_perm = TCP_SOCKET__RECV_MSG;
		break;
J
James Morris 已提交
4149 4150 4151 4152 4153
	case SECCLASS_DCCP_SOCKET:
		netif_perm = NETIF__DCCP_RECV;
		node_perm = NODE__DCCP_RECV;
		recv_perm = DCCP_SOCKET__RECV_MSG;
		break;
L
Linus Torvalds 已提交
4154 4155 4156
	default:
		netif_perm = NETIF__RAWIP_RECV;
		node_perm = NODE__RAWIP_RECV;
4157
		recv_perm = 0;
L
Linus Torvalds 已提交
4158 4159 4160
		break;
	}

4161
	err = sel_netif_sid(skb->iif, &if_sid);
L
Linus Torvalds 已提交
4162
	if (err)
4163 4164 4165 4166
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
	if (err)
		return err;
4167

4168
	err = sel_netnode_sid(addrp, family, &node_sid);
L
Linus Torvalds 已提交
4169
	if (err)
4170 4171
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
L
Linus Torvalds 已提交
4172
	if (err)
4173
		return err;
L
Linus Torvalds 已提交
4174

4175 4176
	if (!recv_perm)
		return 0;
P
Paul Moore 已提交
4177 4178
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.sport), &port_sid);
4179 4180 4181 4182 4183
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_sock_rcv_skb_iptables_compat(),"
		       " network port label not found\n");
4184
		return err;
4185
	}
4186 4187
	return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
}
L
Linus Torvalds 已提交
4188

4189
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4190
				       u16 family)
4191
{
4192
	int err = 0;
4193 4194 4195
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4196 4197 4198 4199 4200 4201 4202 4203 4204
	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
4205

4206
	if (selinux_compat_net)
4207
		err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4208
							   family, addrp);
4209
	else if (selinux_secmark_enabled())
4210
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4211
				   PACKET__RECV, &ad);
4212 4213 4214 4215 4216 4217 4218 4219
	if (err)
		return err;

	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,
4220
				   SECCLASS_PEER, PEER__RECV, &ad);
4221 4222
		if (err)
			selinux_netlbl_err(skb, err, 0);
4223
	} else {
4224
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4225 4226
		if (err)
			return err;
4227
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4228
	}
4229

4230 4231 4232 4233 4234
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4235
	int err;
4236
	struct sk_security_struct *sksec = sk->sk_security;
4237 4238 4239 4240
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
	struct avc_audit_data ad;
	char *addrp;
4241 4242
	u8 secmark_active;
	u8 peerlbl_active;
4243 4244

	if (family != PF_INET && family != PF_INET6)
4245
		return 0;
4246 4247

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4248
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4249 4250
		family = PF_INET;

4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262
	/* 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. */
	if (selinux_compat_net || !selinux_policycap_netpeer)
		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;

4263
	AVC_AUDIT_DATA_INIT(&ad, NET);
4264
	ad.u.net.netif = skb->iif;
4265
	ad.u.net.family = family;
4266
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4267
	if (err)
4268
		return err;
4269

4270
	if (peerlbl_active) {
4271 4272 4273
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4274 4275 4276 4277
		if (err)
			return err;
		err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
					       peer_sid, &ad);
4278 4279
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4280
			return err;
4281
		}
4282 4283
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4284 4285
		if (err)
			selinux_netlbl_err(skb, err, 0);
4286 4287
	}

4288
	if (secmark_active) {
4289 4290 4291 4292 4293 4294
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4295
	return err;
L
Linus Torvalds 已提交
4296 4297
}

C
Catherine Zhang 已提交
4298 4299
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4300 4301 4302 4303 4304 4305
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4306
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4307 4308

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4309

4310 4311
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4312 4313 4314
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4315
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4316 4317 4318 4319
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4320 4321
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337
	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);
4338
out:
L
Linus Torvalds 已提交
4339 4340 4341
	return err;
}

4342
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4343
{
4344
	u32 peer_secid = SECSID_NULL;
4345
	u16 family;
C
Catherine Zhang 已提交
4346

4347 4348 4349 4350 4351
	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)
4352 4353 4354 4355 4356
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4357
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4358
	else if (skb)
4359
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4360

4361
out:
4362
	*secid = peer_secid;
4363 4364 4365
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4366 4367
}

A
Al Viro 已提交
4368
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4369 4370 4371 4372 4373 4374 4375 4376 4377
{
	return sk_alloc_security(sk, family, priority);
}

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

4378
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4379
{
4380 4381
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4382

4383 4384
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4385
	newssec->sclass = ssec->sclass;
4386

4387
	selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4388 4389
}

V
Venkat Yekkirala 已提交
4390
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4391
{
4392
	if (!sk)
V
Venkat Yekkirala 已提交
4393
		*secid = SECINITSID_ANY_SOCKET;
4394 4395
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4396

V
Venkat Yekkirala 已提交
4397
		*secid = sksec->sid;
4398
	}
4399 4400
}

4401
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4402 4403 4404 4405
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4406 4407 4408
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4409
	sksec->sclass = isec->sclass;
4410 4411
}

4412 4413
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4414 4415 4416
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4417
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4418
	u32 newsid;
4419 4420
	u32 peersid;

4421 4422 4423 4424 4425
	/* 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);
4426 4427
	if (err)
		return err;
4428 4429
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4430
		req->peer_secid = SECSID_NULL;
4431 4432 4433
		return 0;
	}

4434 4435 4436 4437 4438
	err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
	if (err)
		return err;

	req->secid = newsid;
4439
	req->peer_secid = peersid;
4440 4441 4442
	return 0;
}

4443 4444
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4445 4446 4447 4448
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4449
	newsksec->peer_sid = req->peer_secid;
4450 4451 4452 4453
	/* 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. */
4454

P
Paul Moore 已提交
4455 4456 4457
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
	selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
4458 4459
}

4460
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4461
{
4462
	u16 family = sk->sk_family;
4463 4464
	struct sk_security_struct *sksec = sk->sk_security;

4465 4466 4467 4468 4469
	/* 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);
4470 4471

	selinux_netlbl_inet_conn_established(sk, family);
4472 4473
}

4474 4475
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4476 4477 4478 4479
{
	fl->secid = req->secid;
}

L
Linus Torvalds 已提交
4480 4481 4482 4483 4484 4485 4486
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;
4487

L
Linus Torvalds 已提交
4488 4489 4490 4491
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4492
	nlh = nlmsg_hdr(skb);
4493

L
Linus Torvalds 已提交
4494 4495 4496
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4497
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4498 4499 4500
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4501
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517
				err = 0;
		}

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

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

#ifdef CONFIG_NETFILTER

4518 4519
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4520
{
4521
	int err;
4522 4523 4524 4525
	char *addrp;
	u32 peer_sid;
	struct avc_audit_data ad;
	u8 secmark_active;
4526
	u8 netlbl_active;
4527
	u8 peerlbl_active;
4528

4529 4530
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4531

4532
	secmark_active = selinux_secmark_enabled();
4533 4534
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4535 4536
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4537

4538 4539 4540
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4541 4542 4543 4544 4545 4546
	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;

4547 4548 4549 4550 4551
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4552
			return NF_DROP;
4553 4554
		}
	}
4555 4556 4557 4558 4559 4560

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

4561 4562 4563 4564 4565 4566 4567 4568
	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;

4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591
	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 */

4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622
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);
}

4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635
static int selinux_ip_postroute_iptables_compat(struct sock *sk,
						int ifindex,
						struct avc_audit_data *ad,
						u16 family, char *addrp)
{
	int err;
	struct sk_security_struct *sksec = sk->sk_security;
	u16 sk_class;
	u32 netif_perm, node_perm, send_perm;
	u32 port_sid, node_sid, if_sid, sk_sid;

	sk_sid = sksec->sid;
	sk_class = sksec->sclass;
L
Linus Torvalds 已提交
4636

4637
	switch (sk_class) {
L
Linus Torvalds 已提交
4638 4639 4640 4641 4642 4643 4644 4645 4646 4647
	case SECCLASS_UDP_SOCKET:
		netif_perm = NETIF__UDP_SEND;
		node_perm = NODE__UDP_SEND;
		send_perm = UDP_SOCKET__SEND_MSG;
		break;
	case SECCLASS_TCP_SOCKET:
		netif_perm = NETIF__TCP_SEND;
		node_perm = NODE__TCP_SEND;
		send_perm = TCP_SOCKET__SEND_MSG;
		break;
J
James Morris 已提交
4648 4649 4650 4651 4652
	case SECCLASS_DCCP_SOCKET:
		netif_perm = NETIF__DCCP_SEND;
		node_perm = NODE__DCCP_SEND;
		send_perm = DCCP_SOCKET__SEND_MSG;
		break;
L
Linus Torvalds 已提交
4653 4654 4655
	default:
		netif_perm = NETIF__RAWIP_SEND;
		node_perm = NODE__RAWIP_SEND;
4656
		send_perm = 0;
L
Linus Torvalds 已提交
4657 4658 4659
		break;
	}

4660
	err = sel_netif_sid(ifindex, &if_sid);
4661
	if (err)
4662 4663 4664
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
		return err;
4665

4666
	err = sel_netnode_sid(addrp, family, &node_sid);
4667
	if (err)
4668 4669
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4670
	if (err)
4671
		return err;
L
Linus Torvalds 已提交
4672

4673 4674 4675
	if (send_perm != 0)
		return 0;

P
Paul Moore 已提交
4676 4677
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.dport), &port_sid);
4678 4679 4680 4681 4682
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_ip_postroute_iptables_compat(),"
		       " network port label not found\n");
4683
		return err;
4684
	}
4685 4686 4687 4688 4689
	return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
}

static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4690
						u16 family)
4691 4692 4693
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4694 4695 4696
	struct avc_audit_data ad;
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4697

4698 4699 4700 4701
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4702 4703 4704 4705 4706 4707
	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;

4708 4709
	if (selinux_compat_net) {
		if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4710
							 &ad, family, addrp))
4711
			return NF_DROP;
4712
	} else if (selinux_secmark_enabled()) {
4713
		if (avc_has_perm(sksec->sid, skb->secmark,
4714
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4715
			return NF_DROP;
L
Linus Torvalds 已提交
4716
	}
4717 4718

	if (selinux_policycap_netpeer)
4719
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4720 4721 4722
			return NF_DROP;

	return NF_ACCEPT;
4723 4724
}

4725 4726
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4727
{
4728 4729
	u32 secmark_perm;
	u32 peer_sid;
4730 4731
	struct sock *sk;
	struct avc_audit_data ad;
4732 4733 4734
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4735

4736 4737 4738 4739 4740
	/* 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. */
	if (selinux_compat_net || !selinux_policycap_netpeer)
4741
		return selinux_ip_postroute_compat(skb, ifindex, family);
4742
#ifdef CONFIG_XFRM
4743 4744 4745 4746 4747 4748 4749 4750
	/* 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;
4751
#endif
4752 4753 4754 4755 4756
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4757 4758 4759 4760
	/* 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 */
4761
	sk = skb->sk;
4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784
	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 {
4785 4786 4787 4788
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4789

4790 4791 4792 4793 4794 4795
	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;

4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816
	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;
	}
4817

4818
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4819 4820
}

4821 4822 4823 4824 4825
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
4826
{
4827
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4828 4829 4830
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4831 4832 4833 4834 4835
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
4836
{
4837
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

	err = secondary_ops->netlink_send(sk, skb);
	if (err)
		return err;

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

	return err;
}

4857
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4858
{
4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869
	int err;
	struct avc_audit_data ad;

	err = secondary_ops->netlink_recv(skb, capability);
	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,
4870
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4871 4872 4873 4874 4875 4876 4877
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4878
	u32 sid;
L
Linus Torvalds 已提交
4879

J
James Morris 已提交
4880
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4881 4882 4883
	if (!isec)
		return -ENOMEM;

4884
	sid = task_sid(task);
L
Linus Torvalds 已提交
4885
	isec->sclass = sclass;
4886
	isec->sid = sid;
L
Linus Torvalds 已提交
4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902
	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
4903
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921
	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,
4922
			u32 perms)
L
Linus Torvalds 已提交
4923 4924 4925
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4926
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4927 4928 4929 4930 4931 4932

	isec = ipc_perms->security;

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

4933
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950
}

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;
4951
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4952 4953 4954 4955 4956 4957 4958 4959 4960
	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);
4961
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4962

4963
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980
			  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;
4981
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4982 4983 4984 4985 4986 4987

	isec = msq->q_perm.security;

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

4988
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4989 4990 4991 4992 4993 4994 4995 4996
			    MSGQ__ASSOCIATE, &ad);
}

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

4997
	switch (cmd) {
L
Linus Torvalds 已提交
4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015
	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;
	}

5016
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5017 5018 5019 5020 5021 5022 5023 5024
	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;
5025
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038
	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
		 */
5039
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
5040 5041 5042 5043 5044 5045 5046 5047 5048
					     &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? */
5049
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5050 5051 5052
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5053 5054
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5055 5056
	if (!rc)
		/* Can the message be put in the queue? */
5057 5058
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069

	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;
5070
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5071 5072 5073 5074 5075 5076
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, IPC);
5077
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5078

5079
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5080 5081
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5082
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5083 5084 5085 5086 5087 5088 5089 5090 5091
				  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;
5092
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5093 5094 5095 5096 5097 5098 5099 5100 5101
	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);
5102
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5103

5104
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121
			  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;
5122
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5123 5124 5125 5126 5127 5128

	isec = shp->shm_perm.security;

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

5129
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5130 5131 5132 5133 5134 5135 5136 5137 5138
			    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;

5139
	switch (cmd) {
L
Linus Torvalds 已提交
5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161
	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;
	}

5162
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180
	return err;
}

static int selinux_shm_shmat(struct shmid_kernel *shp,
			     char __user *shmaddr, int shmflg)
{
	u32 perms;
	int rc;

	rc = secondary_ops->shm_shmat(shp, shmaddr, shmflg);
	if (rc)
		return rc;

	if (shmflg & SHM_RDONLY)
		perms = SHM__READ;
	else
		perms = SHM__READ | SHM__WRITE;

5181
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5182 5183 5184 5185 5186 5187 5188
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5189
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5190 5191 5192 5193 5194 5195 5196 5197 5198
	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);
5199
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5200

5201
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218
			  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;
5219
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5220 5221 5222 5223 5224 5225

	isec = sma->sem_perm.security;

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

5226
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5227 5228 5229 5230 5231 5232 5233 5234 5235
			    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;

5236
	switch (cmd) {
L
Linus Torvalds 已提交
5237 5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267
	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;
	}

5268
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281
	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;

5282
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297
}

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;

5298
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5299 5300
}

5301 5302 5303 5304 5305 5306
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5307
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5308 5309 5310 5311 5312 5313
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5314
			       char *name, char **value)
L
Linus Torvalds 已提交
5315
{
5316
	const struct task_security_struct *__tsec;
5317
	u32 sid;
L
Linus Torvalds 已提交
5318
	int error;
5319
	unsigned len;
L
Linus Torvalds 已提交
5320 5321

	if (current != p) {
5322
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5323 5324 5325 5326
		if (error)
			return error;
	}

5327 5328
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5329 5330

	if (!strcmp(name, "current"))
5331
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5332
	else if (!strcmp(name, "prev"))
5333
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5334
	else if (!strcmp(name, "exec"))
5335
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5336
	else if (!strcmp(name, "fscreate"))
5337
		sid = __tsec->create_sid;
5338
	else if (!strcmp(name, "keycreate"))
5339
		sid = __tsec->keycreate_sid;
5340
	else if (!strcmp(name, "sockcreate"))
5341
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5342
	else
5343 5344
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5345 5346 5347 5348

	if (!sid)
		return 0;

5349 5350 5351 5352
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5353 5354 5355 5356

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5357 5358 5359 5360 5361 5362
}

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
5363
	struct task_struct *tracer;
D
David Howells 已提交
5364 5365
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380
	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"))
5381
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5382
	else if (!strcmp(name, "fscreate"))
5383
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5384
	else if (!strcmp(name, "keycreate"))
5385
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5386
	else if (!strcmp(name, "sockcreate"))
5387
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5388
	else if (!strcmp(name, "current"))
5389
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401
	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);
5402 5403 5404 5405 5406 5407
		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
5408 5409 5410 5411
		if (error)
			return error;
	}

D
David Howells 已提交
5412 5413 5414 5415
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5416 5417 5418
	/* 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
5419
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5420 5421
	   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
5422 5423
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5424
		tsec->exec_sid = sid;
D
David Howells 已提交
5425
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5426
		tsec->create_sid = sid;
D
David Howells 已提交
5427
	} else if (!strcmp(name, "keycreate")) {
5428 5429
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5430
			goto abort_change;
5431
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5432
	} else if (!strcmp(name, "sockcreate")) {
5433
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5434 5435
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5436
		if (sid == 0)
D
David Howells 已提交
5437 5438 5439 5440 5441 5442 5443 5444
			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;
5445
		}
L
Linus Torvalds 已提交
5446 5447 5448

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5449
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5450
		if (error)
D
David Howells 已提交
5451
			goto abort_change;
L
Linus Torvalds 已提交
5452 5453 5454

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5455
		ptsid = 0;
L
Linus Torvalds 已提交
5456
		task_lock(p);
5457
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5458 5459 5460 5461 5462 5463 5464
		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
5465
			if (error)
D
David Howells 已提交
5466
				goto abort_change;
L
Linus Torvalds 已提交
5467 5468
		}

D
David Howells 已提交
5469 5470 5471 5472 5473 5474 5475
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5476
	return size;
D
David Howells 已提交
5477 5478 5479 5480

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5481 5482
}

5483 5484 5485 5486 5487
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5488
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5489 5490 5491 5492
{
	return security_context_to_sid(secdata, seclen, secid);
}

5493 5494
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5495
	kfree(secdata);
5496 5497
}

5498 5499
#ifdef CONFIG_KEYS

D
David Howells 已提交
5500
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5501
			     unsigned long flags)
5502
{
D
David Howells 已提交
5503
	const struct task_security_struct *tsec;
5504 5505 5506 5507 5508 5509
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5510 5511 5512
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5513
	else
D
David Howells 已提交
5514
		ksec->sid = tsec->sid;
5515

5516
	k->security = ksec;
5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528
	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
5529 5530
				  const struct cred *cred,
				  key_perm_t perm)
5531 5532 5533
{
	struct key *key;
	struct key_security_struct *ksec;
5534
	u32 sid;
5535 5536 5537 5538 5539 5540 5541

	/* 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
5542
	sid = cred_sid(cred);
5543 5544 5545 5546 5547

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5548 5549
}

5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563
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;
}

5564 5565
#endif

L
Linus Torvalds 已提交
5566
static struct security_operations selinux_ops = {
5567 5568
	.name =				"selinux",

5569 5570
	.ptrace_may_access =		selinux_ptrace_may_access,
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5571
	.capget =			selinux_capget,
D
David Howells 已提交
5572
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5573 5574 5575 5576 5577 5578 5579 5580
	.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,
5581
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5582

5583
	.bprm_set_creds =		selinux_bprm_set_creds,
L
Linus Torvalds 已提交
5584
	.bprm_check_security =		selinux_bprm_check_security,
5585 5586
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5587 5588 5589 5590 5591
	.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,
5592
	.sb_kern_mount =		selinux_sb_kern_mount,
5593
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5594 5595 5596
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5597
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5598
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5599 5600
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5601 5602 5603

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5604
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622
	.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,
5623 5624 5625
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5626 5627
	.inode_need_killpriv =		selinux_inode_need_killpriv,
	.inode_killpriv =		selinux_inode_killpriv,
5628
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641

	.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,

5642
	.dentry_open =			selinux_dentry_open,
5643

L
Linus Torvalds 已提交
5644
	.task_create =			selinux_task_create,
5645
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5646 5647
	.cred_prepare =			selinux_cred_prepare,
	.cred_commit =			selinux_cred_commit,
5648 5649
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
L
Linus Torvalds 已提交
5650
	.task_setuid =			selinux_task_setuid,
D
David Howells 已提交
5651
	.task_fix_setuid =		selinux_task_fix_setuid,
L
Linus Torvalds 已提交
5652 5653 5654
	.task_setgid =			selinux_task_setgid,
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5655
	.task_getsid =			selinux_task_getsid,
5656
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5657 5658
	.task_setgroups =		selinux_task_setgroups,
	.task_setnice =			selinux_task_setnice,
5659
	.task_setioprio =		selinux_task_setioprio,
5660
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5661 5662 5663
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5664
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5665 5666 5667
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
	.task_prctl =			selinux_task_prctl,
5668
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5669 5670

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

	.msg_msg_alloc_security =	selinux_msg_msg_alloc_security,
	.msg_msg_free_security =	selinux_msg_msg_free_security,

	.msg_queue_alloc_security =	selinux_msg_queue_alloc_security,
	.msg_queue_free_security =	selinux_msg_queue_free_security,
	.msg_queue_associate =		selinux_msg_queue_associate,
	.msg_queue_msgctl =		selinux_msg_queue_msgctl,
	.msg_queue_msgsnd =		selinux_msg_queue_msgsnd,
	.msg_queue_msgrcv =		selinux_msg_queue_msgrcv,

	.shm_alloc_security =		selinux_shm_alloc_security,
	.shm_free_security =		selinux_shm_free_security,
	.shm_associate =		selinux_shm_associate,
	.shm_shmctl =			selinux_shm_shmctl,
	.shm_shmat =			selinux_shm_shmat,

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

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

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

5700
	.secid_to_secctx =		selinux_secid_to_secctx,
5701
	.secctx_to_secid =		selinux_secctx_to_secid,
5702 5703
	.release_secctx =		selinux_release_secctx,

5704
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5705 5706 5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720
	.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
5721 5722
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5723 5724
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5725
	.sk_clone_security =		selinux_sk_clone_security,
5726
	.sk_getsecid =			selinux_sk_getsecid,
5727 5728 5729
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5730
	.inet_conn_established =	selinux_inet_conn_established,
5731
	.req_classify_flow =		selinux_req_classify_flow,
5732 5733 5734 5735 5736

#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
5737
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5738 5739
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5740
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5741
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5742 5743
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5744
#endif
5745 5746

#ifdef CONFIG_KEYS
5747 5748 5749
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5750
	.key_getsecurity =		selinux_key_getsecurity,
5751
#endif
5752 5753 5754 5755 5756 5757 5758

#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
5759 5760 5761 5762
};

static __init int selinux_init(void)
{
5763 5764 5765 5766 5767
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5768 5769 5770 5771 5772 5773 5774 5775
	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
5776
	cred_init_security();
L
Linus Torvalds 已提交
5777

5778 5779
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5780
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5781 5782
	avc_init();

5783
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5784
	if (!secondary_ops)
5785 5786
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5787 5788
		panic("SELinux: Unable to register with kernel.\n");

5789
	if (selinux_enforcing)
5790
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5791
	else
5792
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5793

L
Linus Torvalds 已提交
5794 5795 5796 5797 5798
	return 0;
}

void selinux_complete_init(void)
{
5799
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5800 5801

	/* Set up any superblocks initialized prior to the policy load. */
5802
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5803
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5804 5805 5806 5807 5808
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5809 5810
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5811 5812 5813
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5814
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5815 5816 5817 5818
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5819
		spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5820 5821 5822 5823 5824
		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5825
	spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5826 5827 5828 5829 5830 5831
}

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

5832
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5833

5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844 5845 5846 5847
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,
5848 5849 5850 5851 5852 5853 5854
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5855
	}
L
Linus Torvalds 已提交
5856 5857 5858 5859
};

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

5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5875 5876 5877 5878 5879 5880 5881 5882 5883 5884
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5885 5886 5887

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

5888 5889 5890
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
5891 5892

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5893 5894 5895
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
5896
#endif	/* IPV6 */
5897

L
Linus Torvalds 已提交
5898 5899 5900 5901 5902 5903 5904 5905 5906
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5907
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5908

5909
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5910
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5911
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5912 5913 5914 5915
#endif	/* IPV6 */
}
#endif

5916
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5917 5918 5919 5920 5921

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5922
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5923 5924

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5925 5926
static int selinux_disabled;

L
Linus Torvalds 已提交
5927 5928 5929 5930 5931 5932 5933 5934 5935 5936 5937 5938 5939 5940 5941 5942 5943
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;
5944
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957

	/* 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