hooks.c 142.6 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
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 *		Paul Moore <paul.moore@hp.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

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

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#define NUM_SEL_MNT_OPTS 5
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extern unsigned int policydb_loaded_version;
extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
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extern 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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	Opt_labelsupport = 5,
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};

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

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

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

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

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

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static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
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			const struct cred *cred)
390
{
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	const struct task_security_struct *tsec = cred->security;
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	int rc;
	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

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

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

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

out_free:
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	security_free_mnt_opts(opts);
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	return rc;
}
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573 574 575
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
576 577
	char mnt_flags = sbsec->flags & SE_MNTMASK;

578
	/* check if the old mount command had the same options */
579
	if (sbsec->flags & SE_SBINITIALIZED)
580 581 582 583 584 585 586
		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
	 */
587 588
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
589 590 591
			return 1;
	return 0;
}
592

593 594 595 596
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
597 598
static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
599
{
600
	const struct cred *cred = current_cred();
601 602 603
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
604 605
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
606 607
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
608 609 610
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
611 612 613 614 615 616 617 618 619 620 621 622 623 624 625

	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
626 627
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
628
		goto out;
629
	}
L
Linus Torvalds 已提交
630

631 632 633 634 635 636 637 638 639 640 641
	/*
	 * 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)
	 */
642
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
643
	    && (num_opts == 0))
644
		goto out;
645

646 647 648 649 650 651 652
	/*
	 * 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;
653 654 655

		if (flags[i] == SE_SBLABELSUPP)
			continue;
656 657
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
658 659 660
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705
			       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
706
		}
707 708
	}

709
	if (sbsec->flags & SE_SBINITIALIZED) {
710
		/* previously mounted with options, but not on this attempt? */
711
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
712 713 714 715 716
			goto out_double_mount;
		rc = 0;
		goto out;
	}

717
	if (strcmp(sb->s_type->name, "proc") == 0)
718
		sbsec->flags |= SE_SBPROC;
719 720

	/* Determine the labeling behavior to use for this filesystem type. */
721
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
722 723
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
724
		       __func__, sb->s_type->name, rc);
725 726
		goto out;
	}
L
Linus Torvalds 已提交
727

728 729
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
730
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
731
		if (rc)
732
			goto out;
L
Linus Torvalds 已提交
733

734
		sbsec->sid = fscontext_sid;
735 736 737 738 739 740 741
	}

	/*
	 * 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.
	 */
742 743
	if (context_sid) {
		if (!fscontext_sid) {
744 745
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
746
			if (rc)
747 748
				goto out;
			sbsec->sid = context_sid;
749
		} else {
750 751
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
752
			if (rc)
753
				goto out;
754
		}
755 756
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
757

758
		sbsec->mntpoint_sid = context_sid;
759
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
760 761
	}

762
	if (rootcontext_sid) {
763 764
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
765
		if (rc)
766
			goto out;
767

768 769
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
770 771
	}

772 773 774 775 776 777
	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
778 779
		}

780 781
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
782
							     sbsec, cred);
783 784 785
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
786

787
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
788 789
	}

790
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
791
out:
792
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
793
	return rc;
794 795 796 797 798
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
799 800
}

801 802
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
803
{
804 805
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
806

807 808 809
	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
810

811 812 813 814 815 816 817 818 819 820 821 822
	/*
	 * 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;
	}
823 824

	/* how can we clone if the old one wasn't set up?? */
825
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
826

827
	/* if fs is reusing a sb, just let its options stand... */
828
	if (newsbsec->flags & SE_SBINITIALIZED)
829 830
		return;

831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849
	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
850
	}
851 852 853 854 855
	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
856

857
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
858 859
	}

860 861 862 863
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

864 865
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
866
{
867
	char *p;
868 869
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
870
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
871

872
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
873

874 875 876 877
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
878

879 880
		if (!*p)
			continue;
L
Linus Torvalds 已提交
881

882
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
883

884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935
		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;
936 937
		case Opt_labelsupport:
			break;
938 939 940 941
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
942 943 944

		}
	}
945

946 947 948 949 950 951 952 953 954 955 956
	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;
	}

957
	if (fscontext) {
958 959
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
960 961
	}
	if (context) {
962 963
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
964 965
	}
	if (rootcontext) {
966 967
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
968 969
	}
	if (defcontext) {
970 971
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
972 973
	}

974 975 976
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

977 978 979 980 981
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
982 983
	return rc;
}
984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010
/*
 * 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
1011

A
Adrian Bunk 已提交
1012 1013
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1014 1015 1016 1017 1018
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1019 1020 1021 1022 1023 1024
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038

		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;
1039 1040 1041 1042
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062
		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);
1063 1064 1065 1066
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1067
		return rc;
1068
	}
1069 1070 1071 1072 1073 1074 1075 1076

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
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;
}

1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
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
1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125
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:
1126 1127 1128 1129
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1130
		case SOCK_DGRAM:
1131 1132 1133 1134
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1135 1136
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1137
		default:
L
Linus Torvalds 已提交
1138 1139 1140 1141 1142 1143 1144 1145 1146
			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;
1147
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
			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;
1161 1162
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1163 1164 1165 1166 1167 1168 1169
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1170 1171
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
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1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184
	}

	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;

1185
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
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1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232
	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;

1233
	mutex_lock(&isec->lock);
L
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1234
	if (isec->initialized)
1235
		goto out_unlock;
L
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1236 1237

	sbsec = inode->i_sb->s_security;
1238
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1239 1240 1241 1242 1243 1244 1245
		/* 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);
1246
		goto out_unlock;
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1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265
	}

	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
1266
			printk(KERN_WARNING "SELinux: %s:  no dentry for dev=%s "
1267
			       "ino=%ld\n", __func__, inode->i_sb->s_id,
L
Linus Torvalds 已提交
1268
			       inode->i_ino);
1269
			goto out_unlock;
L
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1270 1271 1272
		}

		len = INITCONTEXTLEN;
1273
		context = kmalloc(len, GFP_NOFS);
L
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1274 1275 1276
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1277
			goto out_unlock;
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1278 1279 1280 1281 1282 1283 1284 1285 1286
		}
		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);
1287
				goto out_unlock;
L
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1288 1289 1290
			}
			kfree(context);
			len = rc;
1291
			context = kmalloc(len, GFP_NOFS);
L
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1292 1293 1294
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1295
				goto out_unlock;
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			}
			rc = inode->i_op->getxattr(dentry,
						   XATTR_NAME_SELINUX,
						   context, len);
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
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				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1305
				       "%d for dev=%s ino=%ld\n", __func__,
L
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1306 1307
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1308
				goto out_unlock;
L
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1309 1310 1311 1312 1313
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1314
			rc = security_context_to_sid_default(context, rc, &sid,
1315 1316
							     sbsec->def_sid,
							     GFP_NOFS);
L
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1317
			if (rc) {
E
Eric Paris 已提交
1318
				printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
L
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1319
				       "returned %d for dev=%s ino=%ld\n",
1320
				       __func__, context, -rc,
L
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1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344
				       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)
1345
			goto out_unlock;
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1346 1347
		isec->sid = sid;
		break;
1348 1349 1350
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
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1351
	default:
1352
		/* Default to the fs superblock SID. */
L
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1353 1354
		isec->sid = sbsec->sid;

1355
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
L
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			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)
1363
					goto out_unlock;
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1364 1365 1366 1367 1368 1369 1370 1371
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1372 1373
out_unlock:
	mutex_unlock(&isec->lock);
L
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1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406
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
1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419
/*
 * 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);
}

1420
/*
1421
 * Check permission between a pair of tasks, e.g. signal checks,
1422 1423
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1424
 * - this uses the default subjective creds of tsk1
1425 1426 1427
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
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			 u32 perms)
{
1430 1431
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1432

1433 1434 1435 1436 1437
	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
1438 1439
}

1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455
/*
 * 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);
}

1456 1457 1458 1459
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
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1460 1461
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1462
			       const struct cred *cred,
1463
			       int cap, int audit)
L
Linus Torvalds 已提交
1464 1465
{
	struct avc_audit_data ad;
1466
	struct av_decision avd;
1467
	u16 sclass;
1468
	u32 sid = cred_sid(cred);
1469
	u32 av = CAP_TO_MASK(cap);
1470
	int rc;
L
Linus Torvalds 已提交
1471

1472
	AVC_AUDIT_DATA_INIT(&ad, CAP);
L
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1473 1474 1475
	ad.tsk = tsk;
	ad.u.cap = cap;

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

1489
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1490
	if (audit == SECURITY_CAP_AUDIT)
1491
		avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1492
	return rc;
L
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1493 1494 1495 1496 1497 1498
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1499
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1500

1501
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1502 1503 1504 1505 1506 1507
			    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). */
1508
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1509 1510 1511 1512 1513 1514
			  struct inode *inode,
			  u32 perms,
			  struct avc_audit_data *adp)
{
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
1515
	u32 sid;
L
Linus Torvalds 已提交
1516

1517
	if (unlikely(IS_PRIVATE(inode)))
1518 1519
		return 0;

1520
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1521 1522 1523 1524 1525 1526 1527 1528
	isec = inode->i_security;

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

1529
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1530 1531 1532 1533 1534
}

/* 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. */
1535
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1536 1537 1538 1539 1540 1541
				  struct vfsmount *mnt,
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
	struct avc_audit_data ad;
1542

1543
	AVC_AUDIT_DATA_INIT(&ad, FS);
1544 1545
	ad.u.fs.path.mnt = mnt;
	ad.u.fs.path.dentry = dentry;
1546
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1547 1548 1549 1550 1551 1552 1553 1554 1555 1556
}

/* 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. */
1557 1558 1559
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1560 1561
{
	struct file_security_struct *fsec = file->f_security;
1562
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1563
	struct avc_audit_data ad;
1564
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1565 1566 1567
	int rc;

	AVC_AUDIT_DATA_INIT(&ad, FS);
1568
	ad.u.fs.path = file->f_path;
L
Linus Torvalds 已提交
1569

1570 1571
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1572 1573 1574 1575
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1576
			goto out;
L
Linus Torvalds 已提交
1577 1578 1579
	}

	/* av is zero if only checking access to the descriptor. */
1580
	rc = 0;
L
Linus Torvalds 已提交
1581
	if (av)
1582
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1583

1584 1585
out:
	return rc;
L
Linus Torvalds 已提交
1586 1587 1588 1589 1590 1591 1592
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1593 1594
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
1595 1596
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1597
	u32 sid, newsid;
L
Linus Torvalds 已提交
1598 1599 1600 1601 1602 1603
	struct avc_audit_data ad;
	int rc;

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

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

L
Linus Torvalds 已提交
1607
	AVC_AUDIT_DATA_INIT(&ad, FS);
1608
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1609

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

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

1622
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628 1629 1630
	if (rc)
		return rc;

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

1631 1632 1633 1634
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1635
	u32 sid = task_sid(ctx);
1636

1637
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1638 1639
}

1640 1641 1642
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1643 1644 1645 1646 1647 1648 1649 1650 1651

/* Check whether a task can link, unlink, or rmdir a file/directory. */
static int may_link(struct inode *dir,
		    struct dentry *dentry,
		    int kind)

{
	struct inode_security_struct *dsec, *isec;
	struct avc_audit_data ad;
1652
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1653 1654 1655 1656 1657 1658 1659
	u32 av;
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, FS);
1660
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
1661 1662 1663

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1664
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678
	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
1679 1680
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1681 1682 1683
		return 0;
	}

1684
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1685 1686 1687 1688 1689 1690 1691 1692 1693 1694
	return rc;
}

static inline int may_rename(struct inode *old_dir,
			     struct dentry *old_dentry,
			     struct inode *new_dir,
			     struct dentry *new_dentry)
{
	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
	struct avc_audit_data ad;
1695
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706
	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);

1707
	ad.u.fs.path.dentry = old_dentry;
1708
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1709 1710 1711
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1712
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1713 1714 1715 1716
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1717
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1718 1719 1720 1721 1722
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1723
	ad.u.fs.path.dentry = new_dentry;
L
Linus Torvalds 已提交
1724 1725 1726
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1727
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1728 1729 1730 1731 1732
	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);
1733
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1734 1735 1736 1737 1738 1739 1740 1741 1742 1743
				  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. */
1744
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1745 1746 1747 1748 1749
			       struct super_block *sb,
			       u32 perms,
			       struct avc_audit_data *ad)
{
	struct superblock_security_struct *sbsec;
1750
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1751 1752

	sbsec = sb->s_security;
1753
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783
}

/* 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;
}

1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806
/* 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
1807
/*
1808
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1809 1810
 * open permission.
 */
1811
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1812
{
1813
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1814 1815

	if (selinux_policycap_openperm) {
1816
		mode_t mode = file->f_path.dentry->d_inode->i_mode;
E
Eric Paris 已提交
1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830
		/*
		 * 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
1831
			printk(KERN_ERR "SELinux: WARNING: inside %s with "
1832
				"unknown mode:%o\n", __func__, mode);
E
Eric Paris 已提交
1833 1834 1835 1836
	}
	return av;
}

L
Linus Torvalds 已提交
1837 1838
/* Hook functions begin here. */

1839 1840
static int selinux_ptrace_may_access(struct task_struct *child,
				     unsigned int mode)
L
Linus Torvalds 已提交
1841 1842 1843
{
	int rc;

1844
	rc = secondary_ops->ptrace_may_access(child, mode);
L
Linus Torvalds 已提交
1845 1846 1847
	if (rc)
		return rc;

1848
	if (mode == PTRACE_MODE_READ) {
1849 1850 1851
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1852 1853
	}

1854
	return current_has_perm(child, PROCESS__PTRACE);
1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865
}

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
1866 1867 1868
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1869
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1870 1871 1872
{
	int error;

1873
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1874 1875 1876 1877 1878 1879
	if (error)
		return error;

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

D
David Howells 已提交
1880 1881 1882 1883
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
1884 1885 1886
{
	int error;

D
David Howells 已提交
1887 1888
	error = secondary_ops->capset(new, old,
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1889 1890 1891
	if (error)
		return error;

D
David Howells 已提交
1892
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1893 1894
}

1895 1896
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
			   int cap, int audit)
L
Linus Torvalds 已提交
1897 1898 1899
{
	int rc;

1900
	rc = secondary_ops->capable(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1901 1902 1903
	if (rc)
		return rc;

1904
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1905 1906
}

1907 1908 1909 1910 1911 1912
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
{
	int buflen, rc;
	char *buffer, *path, *end;

	rc = -ENOMEM;
1913
	buffer = (char *)__get_free_page(GFP_KERNEL);
1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934
	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;
	}
1935 1936 1937 1938 1939 1940
	buflen -= 4;
	if (buflen < 0)
		goto out_free;
	end -= 4;
	memcpy(end, "/sys", 4);
	path = end;
1941 1942 1943 1944 1945 1946 1947
	rc = security_genfs_sid("proc", path, tclass, sid);
out_free:
	free_page((unsigned long)buffer);
out:
	return rc;
}

L
Linus Torvalds 已提交
1948 1949 1950 1951
static int selinux_sysctl(ctl_table *table, int op)
{
	int error = 0;
	u32 av;
1952
	u32 tsid, sid;
L
Linus Torvalds 已提交
1953 1954 1955 1956 1957 1958
	int rc;

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

1959
	sid = current_sid();
L
Linus Torvalds 已提交
1960

1961 1962
	rc = selinux_sysctl_get_sid(table, (op == 0001) ?
				    SECCLASS_DIR : SECCLASS_FILE, &tsid);
L
Linus Torvalds 已提交
1963 1964 1965 1966 1967 1968 1969
	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 */
1970
	if (op == 001) {
1971
		error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1972 1973 1974 1975 1976 1977 1978 1979
				     SECCLASS_DIR, DIR__SEARCH, NULL);
	} else {
		av = 0;
		if (op & 004)
			av |= FILE__READ;
		if (op & 002)
			av |= FILE__WRITE;
		if (av)
1980
			error = avc_has_perm(sid, tsid,
L
Linus Torvalds 已提交
1981
					     SECCLASS_FILE, av, NULL);
1982
	}
L
Linus Torvalds 已提交
1983 1984 1985 1986 1987 1988

	return error;
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1989
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1990 1991 1992 1993 1994 1995
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1996 1997 1998 1999 2000
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2001
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2002 2003 2004 2005
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2006
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2007 2008 2009 2010
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2011 2012 2013 2014 2015 2016
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2017 2018 2019
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030
}

static int selinux_syslog(int type)
{
	int rc;

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

	switch (type) {
2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047
	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
2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063
	}
	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.
 */
2064
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2065 2066 2067
{
	int rc, cap_sys_admin = 0;

2068 2069
	rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2070 2071 2072
	if (rc == 0)
		cap_sys_admin = 1;

2073
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2074 2075 2076 2077
}

/* binprm security operations */

2078
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2079
{
2080 2081
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2082 2083
	struct inode_security_struct *isec;
	struct avc_audit_data ad;
2084
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2085 2086
	int rc;

2087
	rc = secondary_ops->bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2088 2089 2090
	if (rc)
		return rc;

2091 2092 2093
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2094 2095
		return 0;

2096 2097
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2098 2099 2100
	isec = inode->i_security;

	/* Default to the current task SID. */
2101 2102
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2103

2104
	/* Reset fs, key, and sock SIDs on execve. */
2105 2106 2107
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2108

2109 2110
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2111
		/* Reset exec SID on execve. */
2112
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2113 2114
	} else {
		/* Check for a default transition on this program. */
2115 2116
		rc = security_transition_sid(old_tsec->sid, isec->sid,
					     SECCLASS_PROCESS, &new_tsec->sid);
L
Linus Torvalds 已提交
2117 2118 2119 2120 2121
		if (rc)
			return rc;
	}

	AVC_AUDIT_DATA_INIT(&ad, FS);
2122
	ad.u.fs.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2123

J
Josef Sipek 已提交
2124
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2125
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2126

2127 2128
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2129 2130 2131 2132 2133
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2134
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2135 2136 2137 2138
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2139
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2140 2141 2142 2143
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
		/* 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
2177

2178 2179
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2180 2181 2182 2183 2184
	}

	return 0;
}

2185
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2186
{
2187 2188 2189
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
	u32 sid, osid;
L
Linus Torvalds 已提交
2190 2191
	int atsecure = 0;

2192 2193 2194 2195
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2196 2197 2198
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2199
		atsecure = avc_has_perm(osid, sid,
2200 2201
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2202 2203 2204 2205 2206 2207 2208 2209 2210
	}

	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. */
2211 2212
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2213 2214 2215
{
	struct avc_audit_data ad;
	struct file *file, *devnull = NULL;
2216
	struct tty_struct *tty;
2217
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2218
	long j = -1;
2219
	int drop_tty = 0;
L
Linus Torvalds 已提交
2220

2221
	tty = get_current_tty();
L
Linus Torvalds 已提交
2222 2223
	if (tty) {
		file_list_lock();
2224 2225 2226
		if (!list_empty(&tty->tty_files)) {
			struct inode *inode;

L
Linus Torvalds 已提交
2227 2228 2229 2230 2231
			/* 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. */
2232 2233
			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
			inode = file->f_path.dentry->d_inode;
2234
			if (inode_has_perm(cred, inode,
L
Linus Torvalds 已提交
2235
					   FILE__READ | FILE__WRITE, NULL)) {
2236
				drop_tty = 1;
L
Linus Torvalds 已提交
2237 2238 2239
			}
		}
		file_list_unlock();
A
Alan Cox 已提交
2240
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2241
	}
2242 2243 2244
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2245 2246 2247

	/* Revalidate access to inherited open files. */

2248
	AVC_AUDIT_DATA_INIT(&ad, FS);
L
Linus Torvalds 已提交
2249 2250 2251 2252 2253 2254 2255 2256

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

		j++;
		i = j * __NFDBITS;
2257
		fdt = files_fdtable(files);
2258
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2259
			break;
2260
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2261 2262 2263
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2264
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2265 2266 2267 2268
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2269
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280
						  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) {
2281
						get_file(devnull);
L
Linus Torvalds 已提交
2282
					} else {
2283 2284 2285 2286
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2287 2288
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2305 2306 2307 2308
/*
 * 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
2309
{
2310 2311 2312
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2313

2314 2315 2316
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2317

2318 2319
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2320

2321 2322
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2323

2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340
	/* 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
2341
		}
2342
		update_rlimit_cpu(rlim->rlim_cur);
L
Linus Torvalds 已提交
2343 2344 2345 2346
	}
}

/*
2347 2348
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2349
 */
2350
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2351
{
2352
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2353
	struct itimerval itimer;
2354
	struct sighand_struct *psig;
2355
	u32 osid, sid;
L
Linus Torvalds 已提交
2356
	int rc, i;
2357
	unsigned long flags;
L
Linus Torvalds 已提交
2358

2359 2360 2361 2362
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2363 2364
		return;

2365 2366 2367 2368 2369 2370 2371 2372
	/* 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
2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384
	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);
	}

2385 2386
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2387 2388 2389
	read_lock_irq(&tasklist_lock);
	psig = current->parent->sighand;
	spin_lock_irqsave(&psig->siglock, flags);
L
Linus Torvalds 已提交
2390
	wake_up_interruptible(&current->parent->signal->wait_chldexit);
2391 2392
	spin_unlock_irqrestore(&psig->siglock, flags);
	read_unlock_irq(&tasklist_lock);
L
Linus Torvalds 已提交
2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416
}

/* 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)
{
2417 2418 2419
	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) ||
2420 2421
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
L
Linus Torvalds 已提交
2422 2423 2424 2425 2426 2427 2428
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2429
	} else
L
Linus Torvalds 已提交
2430 2431 2432 2433 2434
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2435 2436
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2437 2438 2439 2440 2441 2442
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2443
	} else
2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455
		*first = 0;

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

2456
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2457 2458 2459 2460
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2461
	int open_quote = 0;
L
Linus Torvalds 已提交
2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476

	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 {
2477 2478 2479 2480
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2481 2482 2483
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2484
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2485 2486 2487 2488 2489 2490 2491
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2492
	strcpy(in_save, nosec_save);
2493
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2494 2495 2496 2497
out:
	return rc;
}

2498
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2499
{
2500
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2501 2502 2503 2504 2505 2506 2507
	struct avc_audit_data ad;
	int rc;

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

2508 2509 2510 2511
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2512
	AVC_AUDIT_DATA_INIT(&ad, FS);
2513
	ad.u.fs.path.dentry = sb->s_root;
2514
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2515 2516
}

2517
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2518
{
2519
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2520 2521
	struct avc_audit_data ad;

2522
	AVC_AUDIT_DATA_INIT(&ad, FS);
2523
	ad.u.fs.path.dentry = dentry->d_sb->s_root;
2524
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2525 2526
}

2527
static int selinux_mount(char *dev_name,
2528
			 struct path *path,
2529 2530 2531
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2532
{
2533
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2534 2535
	int rc;

2536
	rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
L
Linus Torvalds 已提交
2537 2538 2539 2540
	if (rc)
		return rc;

	if (flags & MS_REMOUNT)
2541
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2542
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2543
	else
2544
		return dentry_has_perm(cred, path->mnt, path->dentry,
2545
				       FILE__MOUNTON);
L
Linus Torvalds 已提交
2546 2547 2548 2549
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2550
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2551 2552 2553 2554 2555 2556
	int rc;

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

2557
	return superblock_has_perm(cred, mnt->mnt_sb,
2558
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572
}

/* 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);
}

2573 2574 2575 2576
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
				       char **name, void **value,
				       size_t *len)
{
2577 2578
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
2579 2580
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2581
	u32 sid, newsid, clen;
2582
	int rc;
2583
	char *namep = NULL, *context;
2584 2585 2586 2587

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

2588 2589 2590
	sid = tsec->sid;
	newsid = tsec->create_sid;

2591
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2592
		rc = security_transition_sid(sid, dsec->sid,
2593 2594 2595 2596 2597 2598
					     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",
2599
			       __func__,
2600 2601 2602 2603 2604
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2605
	/* Possibly defer initialization to selinux_complete_init. */
2606
	if (sbsec->flags & SE_SBINITIALIZED) {
2607 2608 2609 2610 2611
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2612

2613
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2614 2615
		return -EOPNOTSUPP;

2616
	if (name) {
2617
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2618 2619 2620 2621
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2622

2623
	if (value && len) {
2624
		rc = security_sid_to_context_force(newsid, &context, &clen);
2625 2626 2627 2628 2629 2630
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2631 2632 2633 2634 2635
	}

	return 0;
}

L
Linus Torvalds 已提交
2636 2637 2638 2639 2640 2641 2642 2643 2644
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;

2645
	rc = secondary_ops->inode_link(old_dentry, dir, new_dentry);
L
Linus Torvalds 已提交
2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687
	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,
2688
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2689 2690 2691 2692 2693 2694
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2695 2696 2697
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2698 2699 2700 2701
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2702
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2703 2704
	int rc;

2705
	rc = secondary_ops->inode_follow_link(dentry, nameidata);
L
Linus Torvalds 已提交
2706 2707
	if (rc)
		return rc;
2708
	return dentry_has_perm(cred, NULL, dentry, FILE__READ);
L
Linus Torvalds 已提交
2709 2710
}

2711
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2712
{
2713
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2714 2715
	int rc;

2716
	rc = secondary_ops->inode_permission(inode, mask);
L
Linus Torvalds 已提交
2717 2718 2719 2720 2721 2722 2723 2724
	if (rc)
		return rc;

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

2725
	return inode_has_perm(cred, inode,
2726
			      file_mask_to_av(inode->i_mode, mask), NULL);
L
Linus Torvalds 已提交
2727 2728 2729 2730
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2731
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742
	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))
2743
		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2744

2745
	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2746 2747 2748 2749
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2750 2751 2752
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2753 2754
}

2755
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2756
{
2757 2758
	const struct cred *cred = current_cred();

2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772
	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. */
2773
	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2774 2775
}

2776 2777
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
2778 2779 2780 2781 2782
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
	struct avc_audit_data ad;
2783
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2784 2785
	int rc = 0;

2786 2787
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2788 2789

	sbsec = inode->i_sb->s_security;
2790
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2791 2792
		return -EOPNOTSUPP;

2793
	if (!is_owner_or_cap(inode))
L
Linus Torvalds 已提交
2794 2795
		return -EPERM;

2796
	AVC_AUDIT_DATA_INIT(&ad, FS);
2797
	ad.u.fs.path.dentry = dentry;
L
Linus Torvalds 已提交
2798

2799
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2800 2801 2802 2803 2804
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2805 2806 2807 2808 2809
	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
2810 2811 2812
	if (rc)
		return rc;

2813
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2814 2815 2816 2817
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2818
	rc = security_validate_transition(isec->sid, newsid, sid,
2819
					  isec->sclass);
L
Linus Torvalds 已提交
2820 2821 2822 2823 2824 2825 2826 2827 2828 2829
	if (rc)
		return rc;

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

2830
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2831
					const void *value, size_t size,
2832
					int flags)
L
Linus Torvalds 已提交
2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843
{
	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;
	}

2844
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2845
	if (rc) {
2846 2847 2848
		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
2849 2850 2851 2852 2853 2854 2855
		return;
	}

	isec->sid = newsid;
	return;
}

2856
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2857
{
2858 2859 2860
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2861 2862
}

2863
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2864
{
2865 2866 2867
	const struct cred *cred = current_cred();

	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2868 2869
}

2870
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2871
{
2872 2873
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2874 2875 2876 2877 2878 2879

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

2880
/*
2881
 * Copy the inode security context value to the user.
2882 2883 2884
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2885
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2886
{
2887 2888 2889
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2890
	struct inode_security_struct *isec = inode->i_security;
2891

2892 2893
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2894

2895 2896 2897 2898 2899 2900 2901 2902 2903
	/*
	 * 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.
	 */
2904 2905
	error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
				SECURITY_CAP_NOAUDIT);
2906 2907 2908 2909 2910
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
	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
2921 2922 2923
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2924
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935
{
	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;

2936
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951
	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;
}

2952 2953 2954 2955 2956 2957 2958 2959 2960 2961
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);
}

2962 2963 2964 2965 2966 2967
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
2968 2969
/* file security operations */

2970
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2971
{
2972
	const struct cred *cred = current_cred();
V
Venkat Yekkirala 已提交
2973
	int rc;
J
Josef Sipek 已提交
2974
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2975 2976 2977 2978 2979 2980 2981 2982 2983 2984

	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;

2985
	rc = file_has_perm(cred, file,
V
Venkat Yekkirala 已提交
2986 2987 2988 2989 2990
			   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
2991 2992
}

2993 2994 2995 2996 2997
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;
2998
	u32 sid = current_sid();
2999 3000 3001 3002 3003 3004

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

3005
	if (sid == fsec->sid && fsec->isid == isec->sid
3006 3007 3008 3009 3010 3011
	    && 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
3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024
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)
{
3025
	const struct cred *cred = current_cred();
3026
	u32 av = 0;
L
Linus Torvalds 已提交
3027

3028 3029 3030 3031 3032 3033
	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
3034

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

static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3040
	const struct cred *cred = current_cred();
D
David Howells 已提交
3041
	int rc = 0;
3042

L
Linus Torvalds 已提交
3043 3044 3045 3046 3047 3048 3049
#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
3050
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3051
		if (rc)
D
David Howells 已提交
3052
			goto error;
L
Linus Torvalds 已提交
3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066
	}
#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;

3067
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3068
	}
D
David Howells 已提交
3069 3070 3071

error:
	return rc;
L
Linus Torvalds 已提交
3072 3073 3074
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3075 3076
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3077
{
3078
	int rc = 0;
3079
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3080

3081 3082 3083 3084
	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
3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097
		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)
{
3098
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3099 3100 3101 3102 3103 3104 3105 3106 3107 3108
	int rc;

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

	if (selinux_checkreqprot)
		prot = reqprot;

#ifndef CONFIG_PPC32
3109 3110 3111 3112
	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
3113
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3114 3115 3116
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3117
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3118 3119 3120 3121 3122 3123 3124 3125
		} 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
3126
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3127
		}
3128 3129 3130
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3131 3132 3133 3134 3135 3136 3137
#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)
{
3138 3139 3140
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3141 3142 3143 3144 3145
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3146
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3147 3148 3149
	int err = 0;

	switch (cmd) {
3150 3151 3152 3153 3154
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3155

3156
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3157
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3158
			break;
3159 3160 3161 3162 3163 3164 3165 3166
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3167
		err = file_has_perm(cred, file, 0);
3168 3169 3170 3171
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3172
#if BITS_PER_LONG == 32
3173 3174 3175
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3176
#endif
3177 3178
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3179
			break;
3180
		}
3181
		err = file_has_perm(cred, file, FILE__LOCK);
3182
		break;
L
Linus Torvalds 已提交
3183 3184 3185 3186 3187 3188 3189 3190 3191 3192
	}

	return err;
}

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

	fsec = file->f_security;
3193
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3194 3195 3196 3197 3198 3199 3200

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3201
	struct file *file;
3202
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3203 3204 3205 3206
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3207
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3208 3209 3210 3211 3212 3213 3214 3215

	fsec = file->f_security;

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

3216
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3217 3218 3219 3220 3221
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3222 3223 3224
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3225 3226
}

3227
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3228 3229 3230 3231
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3232

3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252
	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.
	 */
3253
	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);
3254 3255
}

L
Linus Torvalds 已提交
3256 3257 3258 3259 3260 3261 3262 3263 3264 3265
/* 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;

3266
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3267 3268
}

D
David Howells 已提交
3269 3270 3271 3272
/*
 * 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
3273
{
D
David Howells 已提交
3274 3275 3276 3277
	struct task_security_struct *tsec = cred->security;
	cred->security = NULL;
	kfree(tsec);
}
L
Linus Torvalds 已提交
3278

D
David Howells 已提交
3279 3280 3281 3282 3283 3284 3285 3286
/*
 * 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
3287

D
David Howells 已提交
3288
	old_tsec = old->security;
L
Linus Torvalds 已提交
3289

D
David Howells 已提交
3290 3291 3292
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3293

D
David Howells 已提交
3294
	new->security = tsec;
L
Linus Torvalds 已提交
3295 3296 3297
	return 0;
}

3298
/*
D
David Howells 已提交
3299
 * commit new credentials
3300
 */
D
David Howells 已提交
3301
static void selinux_cred_commit(struct cred *new, const struct cred *old)
L
Linus Torvalds 已提交
3302
{
D
David Howells 已提交
3303
	secondary_ops->cred_commit(new, old);
L
Linus Torvalds 已提交
3304 3305
}

3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349
/*
 * 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
3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360
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
3361 3362
static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
				   int flags)
L
Linus Torvalds 已提交
3363
{
D
David Howells 已提交
3364
	return secondary_ops->task_fix_setuid(new, old, flags);
L
Linus Torvalds 已提交
3365 3366 3367 3368 3369 3370 3371 3372 3373 3374
}

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)
{
3375
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3376 3377 3378 3379
}

static int selinux_task_getpgid(struct task_struct *p)
{
3380
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3381 3382 3383 3384
}

static int selinux_task_getsid(struct task_struct *p)
{
3385
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3386 3387
}

3388 3389
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3390
	*secid = task_sid(p);
3391 3392
}

L
Linus Torvalds 已提交
3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406
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;

3407
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3408 3409
}

3410 3411
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3412 3413 3414 3415 3416 3417
	int rc;

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

3418
	return current_has_perm(p, PROCESS__SETSCHED);
3419 3420
}

3421 3422
static int selinux_task_getioprio(struct task_struct *p)
{
3423
	return current_has_perm(p, PROCESS__GETSCHED);
3424 3425
}

L
Linus Torvalds 已提交
3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437
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
3438
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3439
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3440
		return current_has_perm(current, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3441 3442 3443 3444 3445 3446

	return 0;
}

static int selinux_task_setscheduler(struct task_struct *p, int policy, struct sched_param *lp)
{
3447 3448 3449 3450 3451 3452
	int rc;

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

3453
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3454 3455 3456 3457
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3458
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3459 3460
}

3461 3462
static int selinux_task_movememory(struct task_struct *p)
{
3463
	return current_has_perm(p, PROCESS__SETSCHED);
3464 3465
}

3466 3467
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3468 3469 3470 3471
{
	u32 perm;
	int rc;

3472
	rc = secondary_ops->task_kill(p, info, sig, secid);
L
Linus Torvalds 已提交
3473 3474 3475 3476 3477 3478 3479
	if (rc)
		return rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3480
	if (secid)
3481 3482
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3483
	else
3484
		rc = current_has_perm(p, perm);
3485
	return rc;
L
Linus Torvalds 已提交
3486 3487 3488 3489 3490 3491
}

static int selinux_task_prctl(int option,
			      unsigned long arg2,
			      unsigned long arg3,
			      unsigned long arg4,
D
David Howells 已提交
3492
			      unsigned long arg5)
L
Linus Torvalds 已提交
3493 3494 3495 3496
{
	/* 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
3497
	return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
L
Linus Torvalds 已提交
3498 3499 3500 3501
}

static int selinux_task_wait(struct task_struct *p)
{
3502
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3503 3504 3505 3506 3507 3508
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3509
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3510

3511
	isec->sid = sid;
L
Linus Torvalds 已提交
3512 3513 3514 3515
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3516 3517
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3518 3519 3520 3521
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3522
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534
	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;

3535 3536 3537
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3538
	switch (ih->protocol) {
3539 3540
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3541

3542 3543
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3544 3545 3546 3547 3548 3549 3550 3551 3552

		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;
3553 3554 3555 3556 3557 3558 3559 3560
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3561
		offset += ihlen;
3562
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3563
		if (uh == NULL)
3564
			break;
L
Linus Torvalds 已提交
3565

3566 3567 3568 3569
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3570

J
James Morris 已提交
3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

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

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

3587 3588 3589
	default:
		break;
	}
L
Linus Torvalds 已提交
3590 3591 3592 3593 3594 3595 3596
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3597 3598
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
			struct avc_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3599 3600 3601 3602 3603
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3604
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3605 3606 3607 3608 3609 3610 3611 3612 3613 3614
	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);
3615
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3616 3617 3618
	if (offset < 0)
		goto out;

3619 3620 3621
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3622 3623
	switch (nexthdr) {
	case IPPROTO_TCP: {
3624
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646

		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
3647 3648 3649 3650 3651 3652 3653 3654 3655 3656
	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;
3657
	}
J
James Morris 已提交
3658

L
Linus Torvalds 已提交
3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
3670
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3671
{
3672 3673
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3674 3675 3676

	switch (ad->u.net.family) {
	case PF_INET:
3677
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3678 3679 3680 3681 3682
		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
3683 3684 3685

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3686
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3687 3688 3689 3690 3691
		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
3692 3693
#endif	/* IPV6 */
	default:
3694 3695
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3696 3697
	}

3698 3699 3700 3701
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3702
	return ret;
3703 3704 3705 3706 3707

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3708 3709
}

3710
/**
3711
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3712
 * @skb: the packet
3713
 * @family: protocol family
3714
 * @sid: the packet's peer label SID
3715 3716
 *
 * Description:
3717 3718 3719 3720 3721 3722
 * 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.
3723 3724
 *
 */
3725
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3726
{
3727
	int err;
3728 3729
	u32 xfrm_sid;
	u32 nlbl_sid;
3730
	u32 nlbl_type;
3731 3732

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3733
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3734

3735 3736 3737 3738 3739
	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");
3740
		return -EACCES;
3741
	}
3742 3743

	return 0;
3744 3745
}

L
Linus Torvalds 已提交
3746 3747 3748 3749 3750 3751
/* 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;
3752
	u32 sid;
L
Linus Torvalds 已提交
3753 3754 3755 3756 3757 3758
	int err = 0;

	isec = SOCK_INODE(sock)->i_security;

	if (isec->sid == SECINITSID_KERNEL)
		goto out;
3759
	sid = task_sid(task);
L
Linus Torvalds 已提交
3760

3761
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3762
	ad.u.net.sk = sock->sk;
3763
	err = avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3764 3765 3766 3767 3768 3769 3770 3771

out:
	return err;
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3772 3773 3774 3775
	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
3776 3777 3778 3779 3780
	int err = 0;

	if (kern)
		goto out;

3781 3782 3783 3784 3785
	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
3786 3787 3788 3789 3790

out:
	return err;
}

V
Venkat Yekkirala 已提交
3791 3792
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3793
{
3794 3795
	const struct cred *cred = current_cred();
	const struct task_security_struct *tsec = cred->security;
L
Linus Torvalds 已提交
3796
	struct inode_security_struct *isec;
3797
	struct sk_security_struct *sksec;
3798 3799 3800 3801 3802
	u32 sid, newsid;
	int err = 0;

	sid = tsec->sid;
	newsid = tsec->sockcreate_sid;
L
Linus Torvalds 已提交
3803 3804 3805

	isec = SOCK_INODE(sock)->i_security;

3806 3807 3808 3809 3810 3811 3812
	if (kern)
		isec->sid = SECINITSID_KERNEL;
	else if (newsid)
		isec->sid = newsid;
	else
		isec->sid = sid;

L
Linus Torvalds 已提交
3813 3814 3815
	isec->sclass = socket_type_to_security_class(family, type, protocol);
	isec->initialized = 1;

3816 3817 3818
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3819
		sksec->sclass = isec->sclass;
P
Paul Moore 已提交
3820
		err = selinux_netlbl_socket_post_create(sock);
3821 3822
	}

V
Venkat Yekkirala 已提交
3823
	return err;
L
Linus Torvalds 已提交
3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840
}

/* 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.
3841 3842
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3843 3844 3845 3846 3847 3848 3849 3850 3851 3852
	 */
	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;
3853
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866

		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;
		}

3867 3868 3869 3870 3871 3872
		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
3873 3874
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3875 3876
				if (err)
					goto out;
3877
				AVC_AUDIT_DATA_INIT(&ad, NET);
3878 3879 3880 3881 3882 3883 3884 3885
				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
3886
		}
3887 3888

		switch (isec->sclass) {
3889
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3890 3891
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3892

3893
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3894 3895
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3896 3897 3898 3899 3900

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3901 3902 3903 3904
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3905

3906
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3907 3908
		if (err)
			goto out;
3909 3910

		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3911 3912 3913 3914 3915 3916 3917 3918 3919
		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,
3920
				   isec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3921 3922 3923 3924 3925 3926 3927 3928 3929
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3930
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3931 3932 3933 3934 3935 3936 3937 3938
	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
3939
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3940 3941
	 */
	isec = SOCK_INODE(sock)->i_security;
J
James Morris 已提交
3942 3943
	if (isec->sclass == SECCLASS_TCP_SOCKET ||
	    isec->sclass == SECCLASS_DCCP_SOCKET) {
L
Linus Torvalds 已提交
3944 3945 3946 3947
		struct avc_audit_data ad;
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3948
		u32 sid, perm;
L
Linus Torvalds 已提交
3949 3950 3951

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3952
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3953 3954 3955 3956
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3957
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3958 3959 3960 3961
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3962
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3963 3964 3965
		if (err)
			goto out;

J
James Morris 已提交
3966 3967 3968
		perm = (isec->sclass == SECCLASS_TCP_SOCKET) ?
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3969
		AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3970 3971
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
J
James Morris 已提交
3972
		err = avc_has_perm(isec->sid, sid, isec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3973 3974 3975 3976
		if (err)
			goto out;
	}

3977 3978
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008
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,
4009
				  int size)
L
Linus Torvalds 已提交
4010
{
V
Venkat Yekkirala 已提交
4011 4012 4013 4014 4015 4016 4017
	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
4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035
}

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);
}

4036
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4037
{
4038 4039 4040 4041 4042 4043 4044
	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
4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074
}

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;

4075
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086
	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;
4087

L
Linus Torvalds 已提交
4088 4089 4090
	/* server child socket */
	ssec = newsk->sk_security;
	ssec->peer_sid = isec->sid;
4091 4092 4093
	err = security_sid_mls_copy(other_isec->sid, ssec->peer_sid, &ssec->sid);

	return err;
L
Linus Torvalds 已提交
4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106
}

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;

4107
	AVC_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4108 4109 4110 4111 4112 4113 4114 4115 4116 4117
	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;
}

4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140
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);
}

4141 4142 4143 4144 4145
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
4146
{
4147 4148 4149 4150 4151
	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
4152

4153 4154
	sk_sid = sksec->sid;
	sk_class = sksec->sclass;
L
Linus Torvalds 已提交
4155

4156
	switch (sk_class) {
L
Linus Torvalds 已提交
4157 4158 4159 4160 4161 4162 4163 4164 4165 4166
	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
4167 4168 4169 4170 4171
	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
4172 4173 4174
	default:
		netif_perm = NETIF__RAWIP_RECV;
		node_perm = NODE__RAWIP_RECV;
4175
		recv_perm = 0;
L
Linus Torvalds 已提交
4176 4177 4178
		break;
	}

4179
	err = sel_netif_sid(skb->iif, &if_sid);
L
Linus Torvalds 已提交
4180
	if (err)
4181 4182 4183 4184
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
	if (err)
		return err;
4185

4186
	err = sel_netnode_sid(addrp, family, &node_sid);
L
Linus Torvalds 已提交
4187
	if (err)
4188 4189
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
L
Linus Torvalds 已提交
4190
	if (err)
4191
		return err;
L
Linus Torvalds 已提交
4192

4193 4194
	if (!recv_perm)
		return 0;
P
Paul Moore 已提交
4195 4196
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.sport), &port_sid);
4197 4198 4199 4200 4201
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_sock_rcv_skb_iptables_compat(),"
		       " network port label not found\n");
4202
		return err;
4203
	}
4204 4205
	return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
}
L
Linus Torvalds 已提交
4206

4207
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4208
				       u16 family)
4209
{
4210
	int err = 0;
4211 4212 4213
	struct sk_security_struct *sksec = sk->sk_security;
	u32 peer_sid;
	u32 sk_sid = sksec->sid;
4214 4215 4216 4217 4218 4219 4220 4221 4222
	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
4223

4224
	if (selinux_compat_net)
4225
		err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
4226
							   family, addrp);
4227
	else if (selinux_secmark_enabled())
4228
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4229
				   PACKET__RECV, &ad);
4230 4231 4232 4233 4234 4235 4236 4237
	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,
4238
				   SECCLASS_PEER, PEER__RECV, &ad);
4239 4240
		if (err)
			selinux_netlbl_err(skb, err, 0);
4241
	} else {
4242
		err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4243 4244
		if (err)
			return err;
4245
		err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
L
Linus Torvalds 已提交
4246
	}
4247

4248 4249 4250 4251 4252
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4253
	int err;
4254
	struct sk_security_struct *sksec = sk->sk_security;
4255 4256 4257 4258
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
	struct avc_audit_data ad;
	char *addrp;
4259 4260
	u8 secmark_active;
	u8 peerlbl_active;
4261 4262

	if (family != PF_INET && family != PF_INET6)
4263
		return 0;
4264 4265

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4266
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4267 4268
		family = PF_INET;

4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280
	/* 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;

4281
	AVC_AUDIT_DATA_INIT(&ad, NET);
4282
	ad.u.net.netif = skb->iif;
4283
	ad.u.net.family = family;
4284
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4285
	if (err)
4286
		return err;
4287

4288
	if (peerlbl_active) {
4289 4290 4291
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4292 4293 4294 4295
		if (err)
			return err;
		err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
					       peer_sid, &ad);
4296 4297
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4298
			return err;
4299
		}
4300 4301
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4302 4303
		if (err)
			selinux_netlbl_err(skb, err, 0);
4304 4305
	}

4306
	if (secmark_active) {
4307 4308 4309 4310 4311 4312
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4313
	return err;
L
Linus Torvalds 已提交
4314 4315
}

C
Catherine Zhang 已提交
4316 4317
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4318 4319 4320 4321 4322 4323
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
	struct sk_security_struct *ssec;
	struct inode_security_struct *isec;
4324
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4325 4326

	isec = SOCK_INODE(sock)->i_security;
C
Catherine Zhang 已提交
4327

4328 4329
	if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    isec->sclass == SECCLASS_TCP_SOCKET) {
C
Catherine Zhang 已提交
4330 4331 4332
		ssec = sock->sk->sk_security;
		peer_sid = ssec->peer_sid;
	}
4333
	if (peer_sid == SECSID_NULL) {
L
Linus Torvalds 已提交
4334 4335 4336 4337
		err = -ENOPROTOOPT;
		goto out;
	}

C
Catherine Zhang 已提交
4338 4339
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);

L
Linus Torvalds 已提交
4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355
	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);
4356
out:
L
Linus Torvalds 已提交
4357 4358 4359
	return err;
}

4360
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4361
{
4362
	u32 peer_secid = SECSID_NULL;
4363
	u16 family;
C
Catherine Zhang 已提交
4364

4365 4366 4367 4368 4369
	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)
4370 4371 4372 4373 4374
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4375
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4376
	else if (skb)
4377
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4378

4379
out:
4380
	*secid = peer_secid;
4381 4382 4383
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4384 4385
}

A
Al Viro 已提交
4386
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4387 4388 4389 4390 4391 4392 4393 4394 4395
{
	return sk_alloc_security(sk, family, priority);
}

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

4396
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4397
{
4398 4399
	struct sk_security_struct *ssec = sk->sk_security;
	struct sk_security_struct *newssec = newsk->sk_security;
4400

4401 4402
	newssec->sid = ssec->sid;
	newssec->peer_sid = ssec->peer_sid;
4403
	newssec->sclass = ssec->sclass;
4404

4405
	selinux_netlbl_sk_security_reset(newssec, newsk->sk_family);
4406 4407
}

V
Venkat Yekkirala 已提交
4408
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4409
{
4410
	if (!sk)
V
Venkat Yekkirala 已提交
4411
		*secid = SECINITSID_ANY_SOCKET;
4412 4413
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4414

V
Venkat Yekkirala 已提交
4415
		*secid = sksec->sid;
4416
	}
4417 4418
}

4419
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4420 4421 4422 4423
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4424 4425 4426
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4427
	sksec->sclass = isec->sclass;
4428 4429
}

4430 4431
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4432 4433 4434
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4435
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4436
	u32 newsid;
4437 4438
	u32 peersid;

4439 4440 4441 4442 4443
	/* 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);
4444 4445
	if (err)
		return err;
4446 4447
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4448
		req->peer_secid = SECSID_NULL;
4449 4450 4451
		return 0;
	}

4452 4453 4454 4455 4456
	err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
	if (err)
		return err;

	req->secid = newsid;
4457
	req->peer_secid = peersid;
4458 4459 4460
	return 0;
}

4461 4462
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4463 4464 4465 4466
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4467
	newsksec->peer_sid = req->peer_secid;
4468 4469 4470 4471
	/* 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. */
4472

P
Paul Moore 已提交
4473 4474 4475
	/* 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);
4476 4477
}

4478
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4479
{
4480
	u16 family = sk->sk_family;
4481 4482
	struct sk_security_struct *sksec = sk->sk_security;

4483 4484 4485 4486 4487
	/* 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);
4488 4489

	selinux_netlbl_inet_conn_established(sk, family);
4490 4491
}

4492 4493
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4494 4495 4496 4497
{
	fl->secid = req->secid;
}

L
Linus Torvalds 已提交
4498 4499 4500 4501 4502 4503 4504
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;
4505

L
Linus Torvalds 已提交
4506 4507 4508 4509
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4510
	nlh = nlmsg_hdr(skb);
4511

L
Linus Torvalds 已提交
4512 4513 4514
	err = selinux_nlmsg_lookup(isec->sclass, nlh->nlmsg_type, &perm);
	if (err) {
		if (err == -EINVAL) {
4515
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4516 4517 4518
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
				  nlh->nlmsg_type, isec->sclass);
4519
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535
				err = 0;
		}

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

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

#ifdef CONFIG_NETFILTER

4536 4537
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4538
{
4539
	int err;
4540 4541 4542 4543
	char *addrp;
	u32 peer_sid;
	struct avc_audit_data ad;
	u8 secmark_active;
4544
	u8 netlbl_active;
4545
	u8 peerlbl_active;
4546

4547 4548
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4549

4550
	secmark_active = selinux_secmark_enabled();
4551 4552
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4553 4554
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4555

4556 4557 4558
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4559 4560 4561 4562 4563 4564
	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;

4565 4566 4567 4568 4569
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4570
			return NF_DROP;
4571 4572
		}
	}
4573 4574 4575 4576 4577 4578

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

4579 4580 4581 4582 4583 4584 4585 4586
	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;

4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609
	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 */

4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640
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);
}

4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653
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
4654

4655
	switch (sk_class) {
L
Linus Torvalds 已提交
4656 4657 4658 4659 4660 4661 4662 4663 4664 4665
	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
4666 4667 4668 4669 4670
	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
4671 4672 4673
	default:
		netif_perm = NETIF__RAWIP_SEND;
		node_perm = NODE__RAWIP_SEND;
4674
		send_perm = 0;
L
Linus Torvalds 已提交
4675 4676 4677
		break;
	}

4678
	err = sel_netif_sid(ifindex, &if_sid);
4679
	if (err)
4680 4681 4682
		return err;
	err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
		return err;
4683

4684
	err = sel_netnode_sid(addrp, family, &node_sid);
4685
	if (err)
4686 4687
		return err;
	err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
4688
	if (err)
4689
		return err;
L
Linus Torvalds 已提交
4690

4691 4692 4693
	if (send_perm != 0)
		return 0;

P
Paul Moore 已提交
4694 4695
	err = sel_netport_sid(sk->sk_protocol,
			      ntohs(ad->u.net.dport), &port_sid);
4696 4697 4698 4699 4700
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in"
		       " selinux_ip_postroute_iptables_compat(),"
		       " network port label not found\n");
4701
		return err;
4702
	}
4703 4704 4705 4706 4707
	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,
4708
						u16 family)
4709 4710 4711
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4712 4713 4714
	struct avc_audit_data ad;
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4715

4716 4717 4718 4719
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4720 4721 4722 4723 4724 4725
	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;

4726 4727
	if (selinux_compat_net) {
		if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
4728
							 &ad, family, addrp))
4729
			return NF_DROP;
4730
	} else if (selinux_secmark_enabled()) {
4731
		if (avc_has_perm(sksec->sid, skb->secmark,
4732
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4733
			return NF_DROP;
L
Linus Torvalds 已提交
4734
	}
4735 4736

	if (selinux_policycap_netpeer)
4737
		if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4738 4739 4740
			return NF_DROP;

	return NF_ACCEPT;
4741 4742
}

4743 4744
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4745
{
4746 4747
	u32 secmark_perm;
	u32 peer_sid;
4748 4749
	struct sock *sk;
	struct avc_audit_data ad;
4750 4751 4752
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4753

4754 4755 4756 4757 4758
	/* 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)
4759
		return selinux_ip_postroute_compat(skb, ifindex, family);
4760
#ifdef CONFIG_XFRM
4761 4762 4763 4764 4765 4766 4767 4768
	/* 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;
4769
#endif
4770 4771 4772 4773 4774
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4775 4776 4777 4778
	/* 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 */
4779
	sk = skb->sk;
4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802
	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 {
4803 4804 4805 4806
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4807

4808 4809 4810 4811 4812 4813
	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;

4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834
	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;
	}
4835

4836
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4837 4838
}

4839 4840 4841 4842 4843
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
4844
{
4845
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4846 4847 4848
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4849 4850 4851 4852 4853
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
4854
{
4855
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874
}
#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;
}

4875
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4876
{
4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887
	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,
4888
			    SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4889 4890 4891 4892 4893 4894 4895
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4896
	u32 sid;
L
Linus Torvalds 已提交
4897

J
James Morris 已提交
4898
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4899 4900 4901
	if (!isec)
		return -ENOMEM;

4902
	sid = task_sid(task);
L
Linus Torvalds 已提交
4903
	isec->sclass = sclass;
4904
	isec->sid = sid;
L
Linus Torvalds 已提交
4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920
	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
4921
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939
	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,
4940
			u32 perms)
L
Linus Torvalds 已提交
4941 4942 4943
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
4944
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4945 4946 4947 4948 4949 4950

	isec = ipc_perms->security;

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

4951
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968
}

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;
4969
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4970 4971 4972 4973 4974 4975 4976 4977 4978
	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);
4979
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4980

4981
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998
			  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;
4999
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5000 5001 5002 5003 5004 5005

	isec = msq->q_perm.security;

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

5006
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5007 5008 5009 5010 5011 5012 5013 5014
			    MSGQ__ASSOCIATE, &ad);
}

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

5015
	switch (cmd) {
L
Linus Torvalds 已提交
5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033
	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;
	}

5034
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5035 5036 5037 5038 5039 5040 5041 5042
	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;
5043
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056
	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
		 */
5057
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
L
Linus Torvalds 已提交
5058 5059 5060 5061 5062 5063 5064 5065 5066
					     &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? */
5067
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5068 5069 5070
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5071 5072
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5073 5074
	if (!rc)
		/* Can the message be put in the queue? */
5075 5076
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087

	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;
5088
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5089 5090 5091 5092 5093 5094
	int rc;

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

	AVC_AUDIT_DATA_INIT(&ad, IPC);
5095
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5096

5097
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5098 5099
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5100
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5101 5102 5103 5104 5105 5106 5107 5108 5109
				  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;
5110
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5111 5112 5113 5114 5115 5116 5117 5118 5119
	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);
5120
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5121

5122
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139
			  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;
5140
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5141 5142 5143 5144 5145 5146

	isec = shp->shm_perm.security;

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

5147
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5148 5149 5150 5151 5152 5153 5154 5155 5156
			    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;

5157
	switch (cmd) {
L
Linus Torvalds 已提交
5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179
	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;
	}

5180
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197 5198
	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;

5199
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5200 5201 5202 5203 5204 5205 5206
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
	struct avc_audit_data ad;
5207
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5208 5209 5210 5211 5212 5213 5214 5215 5216
	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);
5217
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5218

5219
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236
			  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;
5237
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5238 5239 5240 5241 5242 5243

	isec = sma->sem_perm.security;

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

5244
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5245 5246 5247 5248 5249 5250 5251 5252 5253
			    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;

5254
	switch (cmd) {
L
Linus Torvalds 已提交
5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285
	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;
	}

5286
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298 5299
	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;

5300
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315
}

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;

5316
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5317 5318
}

5319 5320 5321 5322 5323 5324
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5325
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5326 5327 5328 5329 5330 5331
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5332
			       char *name, char **value)
L
Linus Torvalds 已提交
5333
{
5334
	const struct task_security_struct *__tsec;
5335
	u32 sid;
L
Linus Torvalds 已提交
5336
	int error;
5337
	unsigned len;
L
Linus Torvalds 已提交
5338 5339

	if (current != p) {
5340
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5341 5342 5343 5344
		if (error)
			return error;
	}

5345 5346
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5347 5348

	if (!strcmp(name, "current"))
5349
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5350
	else if (!strcmp(name, "prev"))
5351
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5352
	else if (!strcmp(name, "exec"))
5353
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5354
	else if (!strcmp(name, "fscreate"))
5355
		sid = __tsec->create_sid;
5356
	else if (!strcmp(name, "keycreate"))
5357
		sid = __tsec->keycreate_sid;
5358
	else if (!strcmp(name, "sockcreate"))
5359
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5360
	else
5361 5362
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5363 5364 5365 5366

	if (!sid)
		return 0;

5367 5368 5369 5370
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5371 5372 5373 5374

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5375 5376 5377 5378 5379 5380
}

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
5381
	struct task_struct *tracer;
D
David Howells 已提交
5382 5383
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398
	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"))
5399
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5400
	else if (!strcmp(name, "fscreate"))
5401
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5402
	else if (!strcmp(name, "keycreate"))
5403
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5404
	else if (!strcmp(name, "sockcreate"))
5405
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5406
	else if (!strcmp(name, "current"))
5407
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419
	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);
5420 5421 5422 5423 5424 5425
		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
5426 5427 5428 5429
		if (error)
			return error;
	}

D
David Howells 已提交
5430 5431 5432 5433
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5434 5435 5436
	/* 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
5437
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5438 5439
	   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
5440 5441
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5442
		tsec->exec_sid = sid;
D
David Howells 已提交
5443
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5444
		tsec->create_sid = sid;
D
David Howells 已提交
5445
	} else if (!strcmp(name, "keycreate")) {
5446 5447
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5448
			goto abort_change;
5449
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5450
	} else if (!strcmp(name, "sockcreate")) {
5451
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5452 5453
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5454
		if (sid == 0)
D
David Howells 已提交
5455 5456 5457 5458 5459 5460 5461 5462
			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;
5463
		}
L
Linus Torvalds 已提交
5464 5465 5466

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5467
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5468
		if (error)
D
David Howells 已提交
5469
			goto abort_change;
L
Linus Torvalds 已提交
5470 5471 5472

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5473
		ptsid = 0;
L
Linus Torvalds 已提交
5474
		task_lock(p);
5475
		tracer = tracehook_tracer_task(p);
D
David Howells 已提交
5476 5477 5478 5479 5480 5481 5482
		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
5483
			if (error)
D
David Howells 已提交
5484
				goto abort_change;
L
Linus Torvalds 已提交
5485 5486
		}

D
David Howells 已提交
5487 5488 5489 5490 5491 5492 5493
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5494
	return size;
D
David Howells 已提交
5495 5496 5497 5498

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5499 5500
}

5501 5502 5503 5504 5505
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5506
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5507 5508 5509 5510
{
	return security_context_to_sid(secdata, seclen, secid);
}

5511 5512
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5513
	kfree(secdata);
5514 5515
}

5516 5517
#ifdef CONFIG_KEYS

D
David Howells 已提交
5518
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5519
			     unsigned long flags)
5520
{
D
David Howells 已提交
5521
	const struct task_security_struct *tsec;
5522 5523 5524 5525 5526 5527
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5528 5529 5530
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5531
	else
D
David Howells 已提交
5532
		ksec->sid = tsec->sid;
5533

5534
	k->security = ksec;
5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546
	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
5547 5548
				  const struct cred *cred,
				  key_perm_t perm)
5549 5550 5551
{
	struct key *key;
	struct key_security_struct *ksec;
5552
	u32 sid;
5553 5554 5555 5556 5557 5558 5559

	/* 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
5560
	sid = cred_sid(cred);
5561 5562 5563 5564 5565

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5566 5567
}

5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580 5581
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;
}

5582 5583
#endif

L
Linus Torvalds 已提交
5584
static struct security_operations selinux_ops = {
5585 5586
	.name =				"selinux",

5587 5588
	.ptrace_may_access =		selinux_ptrace_may_access,
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5589
	.capget =			selinux_capget,
D
David Howells 已提交
5590
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5591 5592 5593 5594 5595 5596 5597 5598
	.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,
5599
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5600

5601 5602 5603
	.bprm_set_creds =		selinux_bprm_set_creds,
	.bprm_committing_creds =	selinux_bprm_committing_creds,
	.bprm_committed_creds =		selinux_bprm_committed_creds,
L
Linus Torvalds 已提交
5604 5605 5606 5607 5608
	.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,
5609
	.sb_kern_mount =		selinux_sb_kern_mount,
5610
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5611 5612 5613
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5614
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5615
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5616 5617
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5618 5619 5620

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5621
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639
	.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,
5640 5641 5642
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5643 5644
	.inode_need_killpriv =		selinux_inode_need_killpriv,
	.inode_killpriv =		selinux_inode_killpriv,
5645
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658

	.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,

5659
	.dentry_open =			selinux_dentry_open,
5660

L
Linus Torvalds 已提交
5661
	.task_create =			selinux_task_create,
5662
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5663 5664
	.cred_prepare =			selinux_cred_prepare,
	.cred_commit =			selinux_cred_commit,
5665 5666
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
L
Linus Torvalds 已提交
5667
	.task_setuid =			selinux_task_setuid,
D
David Howells 已提交
5668
	.task_fix_setuid =		selinux_task_fix_setuid,
L
Linus Torvalds 已提交
5669 5670 5671
	.task_setgid =			selinux_task_setgid,
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5672
	.task_getsid =			selinux_task_getsid,
5673
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5674 5675
	.task_setgroups =		selinux_task_setgroups,
	.task_setnice =			selinux_task_setnice,
5676
	.task_setioprio =		selinux_task_setioprio,
5677
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5678 5679 5680
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5681
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5682 5683 5684
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
	.task_prctl =			selinux_task_prctl,
5685
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5686 5687

	.ipc_permission =		selinux_ipc_permission,
5688
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703 5704 5705

	.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,

5706 5707
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5708 5709 5710 5711
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5712
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5713

5714 5715
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5716

5717
	.secid_to_secctx =		selinux_secid_to_secctx,
5718
	.secctx_to_secid =		selinux_secctx_to_secid,
5719 5720
	.release_secctx =		selinux_release_secctx,

5721
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737
	.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
5738 5739
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5740 5741
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5742
	.sk_clone_security =		selinux_sk_clone_security,
5743
	.sk_getsecid =			selinux_sk_getsecid,
5744 5745 5746
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5747
	.inet_conn_established =	selinux_inet_conn_established,
5748
	.req_classify_flow =		selinux_req_classify_flow,
5749 5750 5751 5752 5753

#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
5754
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5755 5756
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5757
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5758
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5759 5760
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5761
#endif
5762 5763

#ifdef CONFIG_KEYS
5764 5765 5766
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5767
	.key_getsecurity =		selinux_key_getsecurity,
5768
#endif
5769 5770 5771 5772 5773 5774 5775

#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
5776 5777 5778 5779
};

static __init int selinux_init(void)
{
5780 5781 5782 5783 5784
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5785 5786 5787 5788 5789 5790 5791 5792
	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
5793
	cred_init_security();
L
Linus Torvalds 已提交
5794

5795 5796
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5797
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5798 5799
	avc_init();

5800
	secondary_ops = security_ops;
L
Linus Torvalds 已提交
5801
	if (!secondary_ops)
5802 5803
		panic("SELinux: No initial security operations\n");
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5804 5805
		panic("SELinux: Unable to register with kernel.\n");

5806
	if (selinux_enforcing)
5807
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5808
	else
5809
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5810

L
Linus Torvalds 已提交
5811 5812 5813 5814 5815
	return 0;
}

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

	/* Set up any superblocks initialized prior to the policy load. */
5819
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5820
	spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5821 5822 5823 5824 5825
	spin_lock(&sb_security_lock);
next_sb:
	if (!list_empty(&superblock_security_head)) {
		struct superblock_security_struct *sbsec =
				list_entry(superblock_security_head.next,
5826 5827
					   struct superblock_security_struct,
					   list);
L
Linus Torvalds 已提交
5828 5829 5830
		struct super_block *sb = sbsec->sb;
		sb->s_count++;
		spin_unlock(&sb_security_lock);
5831
		spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5832 5833 5834 5835
		down_read(&sb->s_umount);
		if (sb->s_root)
			superblock_doinit(sb, NULL);
		drop_super(sb);
5836
		spin_lock(&sb_lock);
L
Linus Torvalds 已提交
5837 5838 5839 5840 5841
		spin_lock(&sb_security_lock);
		list_del_init(&sbsec->list);
		goto next_sb;
	}
	spin_unlock(&sb_security_lock);
5842
	spin_unlock(&sb_lock);
L
Linus Torvalds 已提交
5843 5844 5845 5846 5847 5848
}

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

5849
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5850

5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864
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,
5865 5866 5867 5868 5869 5870 5871
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5872
	}
L
Linus Torvalds 已提交
5873 5874 5875 5876
};

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

5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891
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
5892 5893 5894 5895 5896 5897 5898 5899 5900 5901
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5902 5903 5904

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

5905 5906 5907
	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
5908 5909

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5910 5911 5912
	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
5913
#endif	/* IPV6 */
5914

L
Linus Torvalds 已提交
5915 5916 5917 5918 5919 5920 5921 5922 5923
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5924
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5925

5926
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5927
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5928
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5929 5930 5931 5932
#endif	/* IPV6 */
}
#endif

5933
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5934 5935 5936 5937 5938

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5939
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5940 5941

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5942 5943
static int selinux_disabled;

L
Linus Torvalds 已提交
5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960
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;
5961
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974

	/* 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