hooks.c 141.4 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
 *	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>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
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#include <linux/ext2_fs.h>
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#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#define NUM_SEL_MNT_OPTS 5
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extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);

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

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

/* The 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. */

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	/* check if we were passed the same options twice,
	 * aka someone passed context=a,context=b
	 */
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	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
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			return 1;
	return 0;
}
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/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
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static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
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{
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	const struct cred *cred = current_cred();
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	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
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	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
564 565
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
566 567 568
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
569 570 571 572 573 574 575 576 577 578 579

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
580 581
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
582
		goto out;
583
	}
L
Linus Torvalds 已提交
584

585 586 587 588 589 590 591 592 593 594 595
	/*
	 * 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)
	 */
596
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597
	    && (num_opts == 0))
598
		goto out;
599

600 601 602 603 604 605 606
	/*
	 * 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;
607 608 609

		if (flags[i] == SE_SBLABELSUPP)
			continue;
610 611
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
612 613 614
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659
			       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
660
		}
661 662
	}

663
	if (sbsec->flags & SE_SBINITIALIZED) {
664
		/* previously mounted with options, but not on this attempt? */
665
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 667 668 669 670
			goto out_double_mount;
		rc = 0;
		goto out;
	}

671
	if (strcmp(sb->s_type->name, "proc") == 0)
672
		sbsec->flags |= SE_SBPROC;
673 674

	/* Determine the labeling behavior to use for this filesystem type. */
675
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 677
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678
		       __func__, sb->s_type->name, rc);
679 680
		goto out;
	}
L
Linus Torvalds 已提交
681

682 683
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
684
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
685
		if (rc)
686
			goto out;
L
Linus Torvalds 已提交
687

688
		sbsec->sid = fscontext_sid;
689 690 691 692 693 694 695
	}

	/*
	 * 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.
	 */
696 697
	if (context_sid) {
		if (!fscontext_sid) {
698 699
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
700
			if (rc)
701 702
				goto out;
			sbsec->sid = context_sid;
703
		} else {
704 705
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
706
			if (rc)
707
				goto out;
708
		}
709 710
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
711

712
		sbsec->mntpoint_sid = context_sid;
713
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
714 715
	}

716
	if (rootcontext_sid) {
717 718
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
719
		if (rc)
720
			goto out;
721

722 723
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
724 725
	}

726 727 728 729 730 731
	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
732 733
		}

734 735
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
736
							     sbsec, cred);
737 738 739
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
740

741
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
742 743
	}

744
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
745
out:
746
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
747
	return rc;
748 749 750 751 752
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
753 754
}

755 756
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
757
{
758 759
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
760

761 762 763
	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
764

765 766
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
767
	 * mount options.  thus we can safely deal with this superblock later
768
	 */
769
	if (!ss_initialized)
770
		return;
771 772

	/* how can we clone if the old one wasn't set up?? */
773
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774

775
	/* if fs is reusing a sb, just let its options stand... */
776
	if (newsbsec->flags & SE_SBINITIALIZED)
777 778
		return;

779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797
	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
798
	}
799 800 801 802 803
	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
804

805
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
806 807
	}

808 809 810 811
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

812 813
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
814
{
815
	char *p;
816 817
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
818
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
819

820
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
821

822 823 824 825
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
826

827 828
		if (!*p)
			continue;
L
Linus Torvalds 已提交
829

830
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
831

832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883
		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;
884 885
		case Opt_labelsupport:
			break;
886 887 888 889
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
890 891 892

		}
	}
893

894 895 896 897 898 899 900 901 902 903 904
	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;
	}

905
	if (fscontext) {
906 907
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 909
	}
	if (context) {
910 911
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 913
	}
	if (rootcontext) {
914 915
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 917
	}
	if (defcontext) {
918 919
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 921
	}

922 923 924
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

925 926 927 928 929
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
930 931
	return rc;
}
932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958
/*
 * 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
959

A
Adrian Bunk 已提交
960 961
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
962 963 964 965 966
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
967 968 969 970 971 972
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
973 974 975 976 977 978 979 980 981 982 983 984 985 986

		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;
987 988 989 990
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
991 992
		default:
			BUG();
993
			return;
994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011
		};
		/* 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);
1012 1013 1014 1015
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1016
		return rc;
1017
	}
1018 1019 1020 1021 1022 1023 1024 1025

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048
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;
}

1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
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
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074
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:
1075 1076 1077 1078
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1079
		case SOCK_DGRAM:
1080 1081 1082 1083
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1084 1085
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1086
		default:
L
Linus Torvalds 已提交
1087 1088 1089 1090 1091 1092 1093 1094 1095
			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;
1096
		case NETLINK_INET_DIAG:
L
Linus Torvalds 已提交
1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
			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;
1110 1111
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1112 1113 1114 1115 1116 1117 1118
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1119 1120
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1121 1122 1123 1124 1125 1126
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1127
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1128 1129 1130
				u16 tclass,
				u32 *sid)
{
1131 1132
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1133

1134
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1135 1136 1137
	if (!buffer)
		return -ENOMEM;

1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
		/* each process gets a /proc/PID/ entry. Strip off the
		 * PID part to get a valid selinux labeling.
		 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
		while (path[1] >= '0' && path[1] <= '9') {
			path[1] = '/';
			path++;
		}
		rc = security_genfs_sid("proc", path, tclass, sid);
L
Linus Torvalds 已提交
1150 1151 1152 1153 1154
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1155
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177
				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;

1178
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1179
	if (isec->initialized)
1180
		goto out_unlock;
L
Linus Torvalds 已提交
1181 1182

	sbsec = inode->i_sb->s_security;
1183
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1184 1185 1186 1187 1188 1189 1190
		/* 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);
1191
		goto out_unlock;
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1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210
	}

	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) {
1211 1212 1213 1214 1215 1216 1217 1218 1219
			/*
			 * this is can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as these
			 * will get fixed up the next time we go through
			 * inode_doinit with a dentry, before these inodes could
			 * be used again by userspace.
			 */
1220
			goto out_unlock;
L
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1221 1222 1223
		}

		len = INITCONTEXTLEN;
1224
		context = kmalloc(len+1, GFP_NOFS);
L
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1225 1226 1227
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1228
			goto out_unlock;
L
Linus Torvalds 已提交
1229
		}
1230
		context[len] = '\0';
L
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1231 1232 1233
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1234 1235
			kfree(context);

L
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1236 1237 1238 1239 1240
			/* 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);
1241
				goto out_unlock;
L
Linus Torvalds 已提交
1242 1243
			}
			len = rc;
1244
			context = kmalloc(len+1, GFP_NOFS);
L
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1245 1246 1247
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1248
				goto out_unlock;
L
Linus Torvalds 已提交
1249
			}
1250
			context[len] = '\0';
L
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1251 1252 1253 1254 1255 1256 1257
			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
1258
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1259
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1260 1261
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1262
				goto out_unlock;
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1263 1264 1265 1266 1267
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1268
			rc = security_context_to_sid_default(context, rc, &sid,
1269 1270
							     sbsec->def_sid,
							     GFP_NOFS);
L
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1271
			if (rc) {
1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
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1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302
				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);
1303 1304
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
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1305
		if (rc)
1306
			goto out_unlock;
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1307 1308
		isec->sid = sid;
		break;
1309 1310 1311
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
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1312
	default:
1313
		/* Default to the fs superblock SID. */
L
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1314 1315
		isec->sid = sbsec->sid;

1316
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317
			if (opt_dentry) {
L
Linus Torvalds 已提交
1318
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319
				rc = selinux_proc_get_sid(opt_dentry,
L
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1320 1321 1322
							  isec->sclass,
							  &sid);
				if (rc)
1323
					goto out_unlock;
L
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1324 1325 1326 1327 1328 1329 1330 1331
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1332 1333
out_unlock:
	mutex_unlock(&isec->lock);
L
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1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366
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
1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379
/*
 * 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);
}

1380
/*
1381
 * Check permission between a pair of tasks, e.g. signal checks,
1382 1383
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1384
 * - this uses the default subjective creds of tsk1
1385 1386 1387
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1388 1389
			 u32 perms)
{
1390 1391
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1392

1393 1394 1395 1396 1397
	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
1398 1399
}

1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415
/*
 * 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);
}

1416 1417 1418 1419
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1420 1421
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
1422
			       const struct cred *cred,
1423
			       int cap, int audit)
L
Linus Torvalds 已提交
1424
{
1425
	struct common_audit_data ad;
1426
	struct av_decision avd;
1427
	u16 sclass;
1428
	u32 sid = cred_sid(cred);
1429
	u32 av = CAP_TO_MASK(cap);
1430
	int rc;
L
Linus Torvalds 已提交
1431

1432
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
L
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1433 1434 1435
	ad.tsk = tsk;
	ad.u.cap = cap;

1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446
	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();
1447
		return -EINVAL;
1448
	}
1449

1450
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 1452 1453 1454 1455
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1456
	return rc;
L
Linus Torvalds 已提交
1457 1458 1459 1460 1461 1462
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1463
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1464

1465
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
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1466 1467 1468 1469 1470 1471
			    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). */
1472
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1473 1474
			  struct inode *inode,
			  u32 perms,
1475 1476
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1477 1478
{
	struct inode_security_struct *isec;
1479
	u32 sid;
L
Linus Torvalds 已提交
1480

1481 1482
	validate_creds(cred);

1483
	if (unlikely(IS_PRIVATE(inode)))
1484 1485
		return 0;

1486
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1487 1488
	isec = inode->i_security;

1489
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1490 1491
}

1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
static int inode_has_perm_noadp(const struct cred *cred,
				struct inode *inode,
				u32 perms,
				unsigned flags)
{
	struct common_audit_data ad;

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

L
Linus Torvalds 已提交
1504 1505 1506
/* 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. */
1507
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1508 1509 1510 1511
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1512
	struct common_audit_data ad;
1513

E
Eric Paris 已提交
1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
	return inode_has_perm(cred, inode, av, &ad, 0);
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the path to help the auditing code to more easily generate the
   pathname if needed. */
static inline int path_has_perm(const struct cred *cred,
				struct path *path,
				u32 av)
{
	struct inode *inode = path->dentry->d_inode;
	struct common_audit_data ad;

1529
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
E
Eric Paris 已提交
1530
	ad.u.path = *path;
1531
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1532 1533 1534 1535 1536 1537 1538 1539 1540 1541
}

/* 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. */
1542 1543 1544
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1545 1546
{
	struct file_security_struct *fsec = file->f_security;
1547
	struct inode *inode = file->f_path.dentry->d_inode;
1548
	struct common_audit_data ad;
1549
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1550 1551
	int rc;

1552 1553
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1554

1555 1556
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1557 1558 1559 1560
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1561
			goto out;
L
Linus Torvalds 已提交
1562 1563 1564
	}

	/* av is zero if only checking access to the descriptor. */
1565
	rc = 0;
L
Linus Torvalds 已提交
1566
	if (av)
1567
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1568

1569 1570
out:
	return rc;
L
Linus Torvalds 已提交
1571 1572 1573 1574 1575 1576 1577
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1578
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1579 1580
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1581
	u32 sid, newsid;
1582
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1583 1584 1585 1586 1587
	int rc;

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

1588 1589 1590
	sid = tsec->sid;
	newsid = tsec->create_sid;

1591 1592
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1593

1594
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1595 1596 1597 1598 1599
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1600
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 1602
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1603 1604 1605 1606
		if (rc)
			return rc;
	}

1607
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1608 1609 1610 1611 1612 1613 1614 1615
	if (rc)
		return rc;

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

1616 1617 1618 1619
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1620
	u32 sid = task_sid(ctx);
1621

1622
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623 1624
}

1625 1626 1627
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1628 1629 1630 1631 1632 1633 1634 1635

/* 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;
1636
	struct common_audit_data ad;
1637
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1638 1639 1640 1641 1642 1643
	u32 av;
	int rc;

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

1644 1645
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1646 1647 1648

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663
	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
1664 1665
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1666 1667 1668
		return 0;
	}

1669
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1670 1671 1672 1673 1674 1675 1676 1677 1678
	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;
1679
	struct common_audit_data ad;
1680
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1681 1682 1683 1684 1685 1686 1687 1688 1689
	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;

1690
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
L
Linus Torvalds 已提交
1691

1692
	ad.u.dentry = old_dentry;
1693
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1694 1695 1696
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1697
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1698 1699 1700 1701
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1702
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1703 1704 1705 1706 1707
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1708
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1709 1710 1711
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1712
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1713 1714 1715 1716 1717
	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);
1718
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1719 1720 1721 1722 1723 1724 1725 1726 1727 1728
				  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. */
1729
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1730 1731
			       struct super_block *sb,
			       u32 perms,
1732
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1733 1734
{
	struct superblock_security_struct *sbsec;
1735
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1736 1737

	sbsec = sb->s_security;
1738
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768
}

/* 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;
}

1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791
/* 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
1792
/*
1793
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1794 1795
 * open permission.
 */
1796
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1797
{
1798
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1799

1800 1801 1802
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1803 1804 1805
	return av;
}

L
Linus Torvalds 已提交
1806 1807
/* Hook functions begin here. */

1808
static int selinux_ptrace_access_check(struct task_struct *child,
1809
				     unsigned int mode)
L
Linus Torvalds 已提交
1810 1811 1812
{
	int rc;

1813
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1814 1815 1816
	if (rc)
		return rc;

1817
	if (mode == PTRACE_MODE_READ) {
1818 1819 1820
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 1822
	}

1823
	return current_has_perm(child, PROCESS__PTRACE);
1824 1825 1826 1827 1828 1829
}

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

1830
	rc = cap_ptrace_traceme(parent);
1831 1832 1833 1834
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1835 1836 1837
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1839 1840 1841
{
	int error;

1842
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1843 1844 1845
	if (error)
		return error;

1846
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1847 1848
}

D
David Howells 已提交
1849 1850 1851 1852
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
1853 1854 1855
{
	int error;

1856
	error = cap_capset(new, old,
D
David Howells 已提交
1857
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1858 1859 1860
	if (error)
		return error;

D
David Howells 已提交
1861
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1862 1863
}

1864 1865 1866 1867 1868 1869 1870 1871 1872 1873
/*
 * (This comment used to live with the selinux_task_setuid hook,
 * which was removed).
 *
 * Since setuid only affects the current process, and since the SELinux
 * controls are not based on the Linux identity attributes, SELinux does not
 * need to control this operation.  However, SELinux does control the use of
 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
 */

1874
static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875
			   struct user_namespace *ns, int cap, int audit)
L
Linus Torvalds 已提交
1876 1877 1878
{
	int rc;

1879
	rc = cap_capable(tsk, cred, ns, cap, audit);
L
Linus Torvalds 已提交
1880 1881 1882
	if (rc)
		return rc;

1883
	return task_has_capability(tsk, cred, cap, audit);
L
Linus Torvalds 已提交
1884 1885 1886 1887
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1888
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1889 1890 1891 1892 1893 1894
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1895 1896 1897 1898 1899
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1900
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 1902 1903 1904
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1905
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 1907 1908 1909
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914 1915
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1916 1917
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1918
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1919 1920
}

1921
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1922 1923 1924 1925
{
	int rc;

	switch (type) {
1926 1927
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1928 1929
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1930 1931 1932 1933
	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
	/* Set level of messages printed to console */
	case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 1935
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1936 1937 1938 1939 1940
	case SYSLOG_ACTION_CLOSE:	/* Close log */
	case SYSLOG_ACTION_OPEN:	/* Open log */
	case SYSLOG_ACTION_READ:	/* Read from log */
	case SYSLOG_ACTION_READ_CLEAR:	/* Read/clear last kernel messages */
	case SYSLOG_ACTION_CLEAR:	/* Clear ring buffer */
1941 1942 1943
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955
	}
	return rc;
}

/*
 * Check that a process has enough memory to allocate a new virtual
 * mapping. 0 means there is enough memory for the allocation to
 * succeed and -ENOMEM implies there is not.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
1956
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1957 1958 1959
{
	int rc, cap_sys_admin = 0;

1960 1961
	rc = selinux_capable(current, current_cred(),
			     &init_user_ns, CAP_SYS_ADMIN,
1962
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1963 1964 1965
	if (rc == 0)
		cap_sys_admin = 1;

1966
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1967 1968 1969 1970
}

/* binprm security operations */

1971
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1972
{
1973 1974
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1975
	struct inode_security_struct *isec;
1976
	struct common_audit_data ad;
1977
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1978 1979
	int rc;

1980
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1981 1982 1983
	if (rc)
		return rc;

1984 1985 1986
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
1987 1988
		return 0;

1989 1990
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
1991 1992 1993
	isec = inode->i_security;

	/* Default to the current task SID. */
1994 1995
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
1996

1997
	/* Reset fs, key, and sock SIDs on execve. */
1998 1999 2000
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2001

2002 2003
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2004
		/* Reset exec SID on execve. */
2005
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2006 2007
	} else {
		/* Check for a default transition on this program. */
2008
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 2010
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2011 2012 2013 2014
		if (rc)
			return rc;
	}

2015 2016
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2017

J
Josef Sipek 已提交
2018
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2020

2021 2022
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2023 2024 2025 2026 2027
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2028
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2029 2030 2031 2032
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2033
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2034 2035 2036 2037
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055
		/* 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();
2056
			tracer = ptrace_parent(current);
2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070
			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
2071

2072 2073
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2074 2075 2076 2077 2078
	}

	return 0;
}

2079
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2080
{
2081
	const struct task_security_struct *tsec = current_security();
2082
	u32 sid, osid;
L
Linus Torvalds 已提交
2083 2084
	int atsecure = 0;

2085 2086 2087 2088
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2089 2090 2091
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2092
		atsecure = avc_has_perm(osid, sid,
2093 2094
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2095 2096
	}

2097
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2098 2099 2100 2101 2102 2103
}

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

/* Derived from fs/exec.c:flush_old_files. */
2104 2105
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2106
{
2107
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2108
	struct file *file, *devnull = NULL;
2109
	struct tty_struct *tty;
2110
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2111
	long j = -1;
2112
	int drop_tty = 0;
L
Linus Torvalds 已提交
2113

2114
	tty = get_current_tty();
L
Linus Torvalds 已提交
2115
	if (tty) {
N
Nick Piggin 已提交
2116
		spin_lock(&tty_files_lock);
2117
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2118
			struct tty_file_private *file_priv;
2119 2120
			struct inode *inode;

L
Linus Torvalds 已提交
2121 2122 2123 2124 2125
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode directly rather
			   than using file_has_perm, as this particular open
			   file may belong to another process and we are only
			   interested in the inode-based check here. */
N
Nick Piggin 已提交
2126 2127 2128
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2129
			inode = file->f_path.dentry->d_inode;
2130 2131
			if (inode_has_perm_noadp(cred, inode,
					   FILE__READ | FILE__WRITE, 0)) {
2132
				drop_tty = 1;
L
Linus Torvalds 已提交
2133 2134
			}
		}
N
Nick Piggin 已提交
2135
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2136
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2137
	}
2138 2139 2140
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2141 2142 2143

	/* Revalidate access to inherited open files. */

2144
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
L
Linus Torvalds 已提交
2145 2146 2147 2148 2149 2150 2151 2152

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

		j++;
		i = j * __NFDBITS;
2153
		fdt = files_fdtable(files);
2154
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2155
			break;
2156
		set = fdt->open_fds->fds_bits[j];
L
Linus Torvalds 已提交
2157 2158 2159
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2160
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2161 2162 2163 2164
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2165
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
						  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) {
2177
						get_file(devnull);
L
Linus Torvalds 已提交
2178
					} else {
2179 2180 2181 2182
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2183 2184
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2201 2202 2203 2204
/*
 * 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
2205
{
2206 2207 2208
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2209

2210 2211 2212
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2213

2214 2215
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2216

2217 2218
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2219

2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232
	/* 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) {
2233 2234
		/* protect against do_prlimit() */
		task_lock(current);
2235 2236 2237 2238
		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
2239
		}
2240 2241
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2242 2243 2244 2245
	}
}

/*
2246 2247
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2248
 */
2249
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2250
{
2251
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2252
	struct itimerval itimer;
2253
	u32 osid, sid;
L
Linus Torvalds 已提交
2254 2255
	int rc, i;

2256 2257 2258 2259
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2260 2261
		return;

2262 2263 2264 2265 2266 2267 2268 2269
	/* 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
2270 2271 2272 2273 2274
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2275 2276 2277 2278 2279
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2280 2281 2282
		spin_unlock_irq(&current->sighand->siglock);
	}

2283 2284
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2285
	read_lock(&tasklist_lock);
2286
	__wake_up_parent(current, current->real_parent);
2287
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311
}

/* 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)
{
2312 2313 2314
	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) ||
2315 2316
		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
2317 2318 2319 2320 2321 2322 2323
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2324
	} else
L
Linus Torvalds 已提交
2325 2326 2327 2328 2329
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2330 2331
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2332 2333 2334 2335 2336 2337
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2338
	} else
2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350
		*first = 0;

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

2351
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2352 2353 2354 2355
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2356
	int open_quote = 0;
L
Linus Torvalds 已提交
2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371

	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 {
2372 2373 2374 2375
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2376 2377 2378
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2379
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2380 2381 2382 2383 2384 2385 2386
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2387
	strcpy(in_save, nosec_save);
2388
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2389 2390 2391 2392
out:
	return rc;
}

2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

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

	if (!data)
		return 0;

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

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

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

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

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

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

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

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

2478
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2479
{
2480
	const struct cred *cred = current_cred();
2481
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2482 2483 2484 2485 2486 2487
	int rc;

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

2488 2489 2490 2491
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2492 2493
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = sb->s_root;
2494
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2495 2496
}

2497
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2498
{
2499
	const struct cred *cred = current_cred();
2500
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2501

2502 2503
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry->d_sb->s_root;
2504
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2505 2506
}

2507
static int selinux_mount(char *dev_name,
2508
			 struct path *path,
2509 2510 2511
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2512
{
2513
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2514 2515

	if (flags & MS_REMOUNT)
2516
		return superblock_has_perm(cred, path->mnt->mnt_sb,
2517
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2518
	else
E
Eric Paris 已提交
2519
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2520 2521 2522 2523
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2524
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2525

2526
	return superblock_has_perm(cred, mnt->mnt_sb,
2527
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541
}

/* 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);
}

2542
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 2544
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2545
{
2546
	const struct task_security_struct *tsec = current_security();
2547 2548
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2549
	u32 sid, newsid, clen;
2550
	int rc;
2551
	char *namep = NULL, *context;
2552 2553 2554 2555

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

2556 2557 2558
	sid = tsec->sid;
	newsid = tsec->create_sid;

2559 2560 2561 2562
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563
		rc = security_transition_sid(sid, dsec->sid,
2564
					     inode_mode_to_security_class(inode->i_mode),
2565
					     qstr, &newsid);
2566 2567 2568 2569
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2570
			       __func__,
2571 2572 2573 2574 2575
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2576
	/* Possibly defer initialization to selinux_complete_init. */
2577
	if (sbsec->flags & SE_SBINITIALIZED) {
2578 2579 2580 2581 2582
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2583

2584
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 2586
		return -EOPNOTSUPP;

2587
	if (name) {
2588
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 2590 2591 2592
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2593

2594
	if (value && len) {
2595
		rc = security_sid_to_context_force(newsid, &context, &clen);
2596 2597 2598 2599 2600 2601
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2602 2603 2604 2605 2606
	}

	return 0;
}

L
Linus Torvalds 已提交
2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

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

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

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

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

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

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

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2644 2645 2646 2647 2648 2649
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2650 2651
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2652
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2653 2654 2655 2656
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2657
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2658

E
Eric Paris 已提交
2659
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2660 2661
}

2662
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2663
{
2664
	const struct cred *cred = current_cred();
2665 2666 2667
	struct common_audit_data ad;
	u32 perms;
	bool from_access;
2668
	unsigned flags = mask & MAY_NOT_BLOCK;
L
Linus Torvalds 已提交
2669

2670
	from_access = mask & MAY_ACCESS;
2671 2672
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2673 2674
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2675 2676
		return 0;

2677 2678
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
2679 2680 2681 2682 2683 2684

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

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

2685
	return inode_has_perm(cred, inode, perms, &ad, flags);
L
Linus Torvalds 已提交
2686 2687 2688 2689
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2690
	const struct cred *cred = current_cred();
2691
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2692

2693 2694 2695 2696 2697 2698 2699
	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
	if (ia_valid & ATTR_FORCE) {
		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
			      ATTR_FORCE);
		if (!ia_valid)
			return 0;
	}
L
Linus Torvalds 已提交
2700

2701 2702
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2703
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2704

E
Eric Paris 已提交
2705
	return dentry_has_perm(cred, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2706 2707 2708 2709
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2710
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2711 2712 2713 2714
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2715

E
Eric Paris 已提交
2716
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2717 2718
}

2719
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2720
{
2721 2722
	const struct cred *cred = current_cred();

2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736
	if (!strncmp(name, XATTR_SECURITY_PREFIX,
		     sizeof XATTR_SECURITY_PREFIX - 1)) {
		if (!strcmp(name, XATTR_NAME_CAPS)) {
			if (!capable(CAP_SETFCAP))
				return -EPERM;
		} else if (!capable(CAP_SYS_ADMIN)) {
			/* A different attribute in the security namespace.
			   Restrict to administrator. */
			return -EPERM;
		}
	}

	/* Not an attribute we recognize, so just check the
	   ordinary setattr permission. */
E
Eric Paris 已提交
2737
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2738 2739
}

2740 2741
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
2742 2743 2744 2745
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2746
	struct common_audit_data ad;
2747
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2748 2749
	int rc = 0;

2750 2751
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2752 2753

	sbsec = inode->i_sb->s_security;
2754
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2755 2756
		return -EOPNOTSUPP;

2757
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2758 2759
		return -EPERM;

2760 2761
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2762

2763
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2764 2765 2766 2767 2768
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2769 2770 2771 2772 2773
	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
2774 2775 2776
	if (rc)
		return rc;

2777
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2778 2779 2780 2781
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2782
	rc = security_validate_transition(isec->sid, newsid, sid,
2783
					  isec->sclass);
L
Linus Torvalds 已提交
2784 2785 2786 2787 2788 2789 2790 2791 2792 2793
	if (rc)
		return rc;

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

2794
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2795
					const void *value, size_t size,
2796
					int flags)
L
Linus Torvalds 已提交
2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807
{
	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;
	}

2808
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2809
	if (rc) {
2810 2811 2812
		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
2813 2814 2815 2816 2817 2818 2819
		return;
	}

	isec->sid = newsid;
	return;
}

2820
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2821
{
2822 2823
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2824
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2825 2826
}

2827
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2828
{
2829 2830
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2831
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2832 2833
}

2834
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2835
{
2836 2837
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2838 2839 2840 2841 2842 2843

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

2844
/*
2845
 * Copy the inode security context value to the user.
2846 2847 2848
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2849
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2850
{
2851 2852 2853
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2854
	struct inode_security_struct *isec = inode->i_security;
2855

2856 2857
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2858

2859 2860 2861 2862 2863 2864 2865 2866 2867
	/*
	 * 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.
	 */
2868 2869
	error = selinux_capable(current, current_cred(),
				&init_user_ns, CAP_MAC_ADMIN,
2870
				SECURITY_CAP_NOAUDIT);
2871 2872 2873 2874 2875
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2876 2877 2878 2879 2880 2881 2882 2883 2884 2885
	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
2886 2887 2888
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2889
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900
{
	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;

2901
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2902 2903 2904 2905
	if (rc)
		return rc;

	isec->sid = newsid;
2906
	isec->initialized = 1;
L
Linus Torvalds 已提交
2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917
	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;
}

2918 2919 2920 2921 2922 2923
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
2924 2925
/* file security operations */

2926
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2927
{
2928
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2929
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2930 2931 2932 2933 2934

	/* 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;

2935 2936
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2937 2938
}

2939 2940
static int selinux_file_permission(struct file *file, int mask)
{
2941 2942 2943 2944 2945
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2946
	if (!mask)
2947 2948 2949
		/* No permission to check.  Existence test. */
		return 0;

2950 2951 2952 2953 2954
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2955 2956 2957
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970
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)
{
2971
	const struct cred *cred = current_cred();
2972
	int error = 0;
L
Linus Torvalds 已提交
2973

2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
	case EXT2_IOC_GETFLAGS:
	/* fall through */
	case EXT2_IOC_GETVERSION:
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
2986

2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998
	case EXT2_IOC_SETFLAGS:
	/* fall through */
	case EXT2_IOC_SETVERSION:
		error = file_has_perm(cred, file, FILE__SETATTR);
		break;

	/* sys_ioctl() checks */
	case FIONBIO:
	/* fall through */
	case FIOASYNC:
		error = file_has_perm(cred, file, 0);
		break;
L
Linus Torvalds 已提交
2999

3000 3001 3002
	case KDSKBENT:
	case KDSKBSENT:
		error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3003
					SECURITY_CAP_AUDIT);
3004 3005 3006 3007 3008 3009 3010 3011 3012
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
		error = file_has_perm(cred, file, FILE__IOCTL);
	}
	return error;
L
Linus Torvalds 已提交
3013 3014
}

3015 3016
static int default_noexec;

L
Linus Torvalds 已提交
3017 3018
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3019
	const struct cred *cred = current_cred();
D
David Howells 已提交
3020
	int rc = 0;
3021

3022 3023
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3024 3025 3026 3027 3028
		/*
		 * 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
3029
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3030
		if (rc)
D
David Howells 已提交
3031
			goto error;
L
Linus Torvalds 已提交
3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044
	}

	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;

3045
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3046
	}
D
David Howells 已提交
3047 3048 3049

error:
	return rc;
L
Linus Torvalds 已提交
3050 3051 3052
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3053 3054
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3055
{
3056
	int rc = 0;
3057
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3058

3059 3060 3061 3062 3063 3064
	/*
	 * notice that we are intentionally putting the SELinux check before
	 * the secondary cap_file_mmap check.  This is such a likely attempt
	 * at bad behaviour/exploit that we always want to get the AVC, even
	 * if DAC would have also denied the operation.
	 */
3065
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3066 3067
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3068 3069 3070 3071 3072 3073
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3074
	if (rc || addr_only)
L
Linus Torvalds 已提交
3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087
		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)
{
3088
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3089 3090 3091 3092

	if (selinux_checkreqprot)
		prot = reqprot;

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

	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)
{
3122 3123 3124
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3125 3126 3127 3128 3129
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3130
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3131 3132 3133
	int err = 0;

	switch (cmd) {
3134 3135 3136 3137 3138
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3139

3140
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3141
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3142
			break;
3143 3144 3145 3146 3147 3148 3149 3150
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3151
		err = file_has_perm(cred, file, 0);
3152 3153 3154 3155
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3156
#if BITS_PER_LONG == 32
3157 3158 3159
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3160
#endif
3161 3162
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3163
			break;
3164
		}
3165
		err = file_has_perm(cred, file, FILE__LOCK);
3166
		break;
L
Linus Torvalds 已提交
3167 3168 3169 3170 3171 3172 3173 3174 3175 3176
	}

	return err;
}

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

	fsec = file->f_security;
3177
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3178 3179 3180 3181 3182 3183 3184

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3185
	struct file *file;
3186
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3187 3188 3189 3190
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3191
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3192 3193 3194 3195 3196 3197 3198 3199

	fsec = file->f_security;

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

3200
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3201 3202 3203 3204 3205
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3206 3207 3208
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3209 3210
}

3211
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3212 3213 3214 3215
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3216

3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236
	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.
	 */
3237
	return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3238 3239
}

L
Linus Torvalds 已提交
3240 3241 3242 3243
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3244
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3245 3246
}

3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261
/*
 * allocate the SELinux part of blank credentials
 */
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
	struct task_security_struct *tsec;

	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;

	cred->security = tsec;
	return 0;
}

D
David Howells 已提交
3262 3263 3264 3265
/*
 * 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
3266
{
D
David Howells 已提交
3267
	struct task_security_struct *tsec = cred->security;
3268

3269 3270 3271 3272 3273
	/*
	 * cred->security == NULL if security_cred_alloc_blank() or
	 * security_prepare_creds() returned an error.
	 */
	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3274
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3275 3276
	kfree(tsec);
}
L
Linus Torvalds 已提交
3277

D
David Howells 已提交
3278 3279 3280 3281 3282 3283 3284 3285
/*
 * 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
3286

D
David Howells 已提交
3287
	old_tsec = old->security;
L
Linus Torvalds 已提交
3288

D
David Howells 已提交
3289 3290 3291
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3292

D
David Howells 已提交
3293
	new->security = tsec;
L
Linus Torvalds 已提交
3294 3295 3296
	return 0;
}

3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307
/*
 * transfer the SELinux data to a blank set of creds
 */
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
{
	const struct task_security_struct *old_tsec = old->security;
	struct task_security_struct *tsec = new->security;

	*tsec = *old_tsec;
}

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
/*
 * 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;
3349
	return ret;
3350 3351
}

3352
static int selinux_kernel_module_request(char *kmod_name)
3353
{
3354 3355 3356 3357 3358 3359 3360 3361 3362 3363
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

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

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3364 3365
}

L
Linus Torvalds 已提交
3366 3367
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3368
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3369 3370 3371 3372
}

static int selinux_task_getpgid(struct task_struct *p)
{
3373
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3374 3375 3376 3377
}

static int selinux_task_getsid(struct task_struct *p)
{
3378
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3379 3380
}

3381 3382
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3383
	*secid = task_sid(p);
3384 3385
}

L
Linus Torvalds 已提交
3386 3387 3388 3389
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3390
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3391 3392 3393
	if (rc)
		return rc;

3394
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3395 3396
}

3397 3398
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3399 3400
	int rc;

3401
	rc = cap_task_setioprio(p, ioprio);
3402 3403 3404
	if (rc)
		return rc;

3405
	return current_has_perm(p, PROCESS__SETSCHED);
3406 3407
}

3408 3409
static int selinux_task_getioprio(struct task_struct *p)
{
3410
	return current_has_perm(p, PROCESS__GETSCHED);
3411 3412
}

3413 3414
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3415
{
3416
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3417 3418 3419 3420

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

	return 0;
}

3428
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3429
{
3430 3431
	int rc;

3432
	rc = cap_task_setscheduler(p);
3433 3434 3435
	if (rc)
		return rc;

3436
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3437 3438 3439 3440
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3441
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3442 3443
}

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

3449 3450
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3451 3452 3453 3454 3455 3456 3457 3458
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3459
	if (secid)
3460 3461
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3462
	else
3463
		rc = current_has_perm(p, perm);
3464
	return rc;
L
Linus Torvalds 已提交
3465 3466 3467 3468
}

static int selinux_task_wait(struct task_struct *p)
{
3469
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3470 3471 3472 3473 3474 3475
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3476
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3477

3478
	isec->sid = sid;
L
Linus Torvalds 已提交
3479 3480 3481 3482
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3483
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3484
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3485 3486 3487 3488
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3489
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501
	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;

3502 3503 3504
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3505
	switch (ih->protocol) {
3506 3507
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3508

3509 3510
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3511 3512 3513 3514 3515 3516 3517 3518 3519

		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;
3520 3521 3522 3523 3524 3525 3526 3527
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3528
		offset += ihlen;
3529
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3530
		if (uh == NULL)
3531
			break;
L
Linus Torvalds 已提交
3532

3533 3534 3535 3536
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3537

J
James Morris 已提交
3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551
	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;
3552
	}
J
James Morris 已提交
3553

3554 3555 3556
	default:
		break;
	}
L
Linus Torvalds 已提交
3557 3558 3559 3560 3561 3562 3563
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3564
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3565
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3566 3567 3568 3569 3570
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;

3571
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3572 3573 3574 3575 3576 3577 3578 3579 3580 3581
	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);
3582
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
L
Linus Torvalds 已提交
3583 3584 3585
	if (offset < 0)
		goto out;

3586 3587 3588
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3589 3590
	switch (nexthdr) {
	case IPPROTO_TCP: {
3591
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613

		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
3614 3615 3616 3617 3618 3619 3620 3621 3622 3623
	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;
3624
	}
J
James Morris 已提交
3625

L
Linus Torvalds 已提交
3626 3627 3628 3629 3630 3631 3632 3633 3634 3635
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3636
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3637
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3638
{
3639 3640
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3641 3642 3643

	switch (ad->u.net.family) {
	case PF_INET:
3644
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3645 3646 3647 3648 3649
		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
3650 3651 3652

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3653
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3654 3655 3656 3657 3658
		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
3659 3660
#endif	/* IPV6 */
	default:
3661 3662
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3663 3664
	}

3665 3666 3667 3668
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3669
	return ret;
3670 3671 3672 3673 3674

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3675 3676
}

3677
/**
3678
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3679
 * @skb: the packet
3680
 * @family: protocol family
3681
 * @sid: the packet's peer label SID
3682 3683
 *
 * Description:
3684 3685 3686 3687 3688 3689
 * 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.
3690 3691
 *
 */
3692
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3693
{
3694
	int err;
3695 3696
	u32 xfrm_sid;
	u32 nlbl_sid;
3697
	u32 nlbl_type;
3698 3699

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3700
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3701

3702 3703 3704 3705 3706
	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");
3707
		return -EACCES;
3708
	}
3709 3710

	return 0;
3711 3712
}

L
Linus Torvalds 已提交
3713
/* socket security operations */
3714

3715 3716
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3717
{
3718 3719 3720 3721 3722 3723 3724
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3725 3726
}

3727
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3728
{
3729
	struct sk_security_struct *sksec = sk->sk_security;
3730
	struct common_audit_data ad;
3731
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3732

3733 3734
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3735

3736
	COMMON_AUDIT_DATA_INIT(&ad, NET);
3737
	ad.u.net.sk = sk;
L
Linus Torvalds 已提交
3738

3739
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3740 3741 3742 3743 3744
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3745
	const struct task_security_struct *tsec = current_security();
3746
	u32 newsid;
3747
	u16 secclass;
3748
	int rc;
L
Linus Torvalds 已提交
3749 3750

	if (kern)
3751
		return 0;
3752 3753

	secclass = socket_type_to_security_class(family, type, protocol);
3754 3755 3756 3757
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3758
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3759 3760
}

V
Venkat Yekkirala 已提交
3761 3762
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3763
{
3764
	const struct task_security_struct *tsec = current_security();
3765
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3766
	struct sk_security_struct *sksec;
3767 3768
	int err = 0;

3769 3770
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3771 3772
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3773 3774 3775 3776 3777
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3778

L
Linus Torvalds 已提交
3779 3780
	isec->initialized = 1;

3781 3782 3783
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3784
		sksec->sclass = isec->sclass;
3785
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3786 3787
	}

V
Venkat Yekkirala 已提交
3788
	return err;
L
Linus Torvalds 已提交
3789 3790 3791 3792 3793 3794 3795 3796
}

/* 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)
{
3797
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3798 3799 3800
	u16 family;
	int err;

3801
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3802 3803 3804 3805 3806
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3807 3808
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3809
	 */
3810
	family = sk->sk_family;
L
Linus Torvalds 已提交
3811 3812
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3813
		struct sk_security_struct *sksec = sk->sk_security;
3814
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3815 3816 3817
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3818
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829

		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;
		}

3830 3831 3832 3833 3834 3835
		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
3836 3837
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3838 3839
				if (err)
					goto out;
3840
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3841 3842
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
3843 3844
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3845 3846 3847 3848
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3849
		}
3850

3851
		switch (sksec->sclass) {
3852
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3853 3854
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3855

3856
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3857 3858
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3859 3860 3861 3862 3863

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3864 3865 3866 3867
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3868

3869
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3870 3871
		if (err)
			goto out;
3872

3873
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3874 3875 3876 3877 3878 3879 3880 3881
		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);

3882 3883
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3884 3885 3886 3887 3888 3889 3890 3891 3892
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3893
	struct sock *sk = sock->sk;
3894
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3895 3896
	int err;

3897
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3898 3899 3900 3901
	if (err)
		return err;

	/*
J
James Morris 已提交
3902
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3903
	 */
3904 3905
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3906
		struct common_audit_data ad;
L
Linus Torvalds 已提交
3907 3908 3909
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3910
		u32 sid, perm;
L
Linus Torvalds 已提交
3911 3912 3913

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3914
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3915 3916 3917 3918
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3919
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3920 3921 3922 3923
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3924
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3925 3926 3927
		if (err)
			goto out;

3928
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3929 3930
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3931
		COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
3932 3933
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
3934
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3935 3936 3937 3938
		if (err)
			goto out;
	}

3939 3940
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3941 3942 3943 3944 3945 3946
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3947
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3948 3949 3950 3951 3952 3953 3954 3955
}

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

3956
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970
	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,
3971
				  int size)
L
Linus Torvalds 已提交
3972
{
3973
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
3974 3975 3976 3977 3978
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
3979
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
3980 3981 3982 3983
}

static int selinux_socket_getsockname(struct socket *sock)
{
3984
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3985 3986 3987 3988
}

static int selinux_socket_getpeername(struct socket *sock)
{
3989
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3990 3991
}

3992
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3993
{
3994 3995
	int err;

3996
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3997 3998 3999 4000
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4001 4002 4003 4004 4005
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4006
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4007 4008 4009 4010
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4011
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4012 4013
}

4014 4015
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4016 4017
					      struct sock *newsk)
{
4018 4019
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4020
	struct sk_security_struct *sksec_new = newsk->sk_security;
4021
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4022 4023
	int err;

4024
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4025
	ad.u.net.sk = other;
L
Linus Torvalds 已提交
4026

4027 4028
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4029 4030 4031 4032 4033
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4034 4035 4036 4037 4038
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4039

4040 4041 4042 4043
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4044 4045 4046 4047 4048
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4049 4050
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4051
	struct common_audit_data ad;
L
Linus Torvalds 已提交
4052

4053
	COMMON_AUDIT_DATA_INIT(&ad, NET);
L
Linus Torvalds 已提交
4054 4055
	ad.u.net.sk = other->sk;

4056 4057
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4058 4059
}

4060 4061
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4062
				    struct common_audit_data *ad)
4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082
{
	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);
}

4083
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4084
				       u16 family)
4085
{
4086
	int err = 0;
4087 4088
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4089
	struct common_audit_data ad;
4090 4091
	char *addrp;

4092
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4093
	ad.u.net.netif = skb->skb_iif;
4094 4095 4096 4097
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4098

4099
	if (selinux_secmark_enabled()) {
4100
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4101
				   PACKET__RECV, &ad);
4102 4103 4104
		if (err)
			return err;
	}
4105

4106 4107 4108 4109
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4110

4111 4112 4113 4114 4115
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4116
	int err;
4117
	struct sk_security_struct *sksec = sk->sk_security;
4118 4119
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4120
	struct common_audit_data ad;
4121
	char *addrp;
4122 4123
	u8 secmark_active;
	u8 peerlbl_active;
4124 4125

	if (family != PF_INET && family != PF_INET6)
4126
		return 0;
4127 4128

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4129
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4130 4131
		family = PF_INET;

4132 4133 4134 4135
	/* 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. */
4136
	if (!selinux_policycap_netpeer)
4137 4138 4139 4140 4141 4142 4143
		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;

4144
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4145
	ad.u.net.netif = skb->skb_iif;
4146
	ad.u.net.family = family;
4147
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4148
	if (err)
4149
		return err;
4150

4151
	if (peerlbl_active) {
4152 4153 4154
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4155 4156
		if (err)
			return err;
4157
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4158
					       peer_sid, &ad);
4159 4160
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4161
			return err;
4162
		}
4163 4164
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4165 4166
		if (err)
			selinux_netlbl_err(skb, err, 0);
4167 4168
	}

4169
	if (secmark_active) {
4170 4171 4172 4173 4174 4175
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4176
	return err;
L
Linus Torvalds 已提交
4177 4178
}

C
Catherine Zhang 已提交
4179 4180
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4181 4182 4183 4184
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4185
	struct sk_security_struct *sksec = sock->sk->sk_security;
4186
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4187

4188 4189
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4190
		peer_sid = sksec->peer_sid;
4191 4192
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4193

C
Catherine Zhang 已提交
4194
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4195
	if (err)
4196
		return err;
L
Linus Torvalds 已提交
4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212

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

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

out_len:
	if (put_user(scontext_len, optlen))
		err = -EFAULT;
	kfree(scontext);
	return err;
}

4213
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4214
{
4215
	u32 peer_secid = SECSID_NULL;
4216
	u16 family;
C
Catherine Zhang 已提交
4217

4218 4219 4220 4221 4222
	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)
4223 4224 4225 4226 4227
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4228
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4229
	else if (skb)
4230
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4231

4232
out:
4233
	*secid = peer_secid;
4234 4235 4236
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4237 4238
}

A
Al Viro 已提交
4239
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4240
{
4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252
	struct sk_security_struct *sksec;

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

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4253 4254 4255 4256
}

static void selinux_sk_free_security(struct sock *sk)
{
4257 4258 4259 4260 4261
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4262 4263
}

4264
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4265
{
4266 4267
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4268

4269 4270 4271
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4272

4273
	selinux_netlbl_sk_security_reset(newsksec);
4274 4275
}

V
Venkat Yekkirala 已提交
4276
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4277
{
4278
	if (!sk)
V
Venkat Yekkirala 已提交
4279
		*secid = SECINITSID_ANY_SOCKET;
4280 4281
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4282

V
Venkat Yekkirala 已提交
4283
		*secid = sksec->sid;
4284
	}
4285 4286
}

4287
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4288 4289 4290 4291
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4292 4293 4294
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4295
	sksec->sclass = isec->sclass;
4296 4297
}

4298 4299
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4300 4301 4302
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4303
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4304
	u32 newsid;
4305 4306
	u32 peersid;

4307 4308 4309 4310 4311
	/* 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);
4312 4313
	if (err)
		return err;
4314 4315
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4316
		req->peer_secid = SECSID_NULL;
4317 4318 4319 4320 4321 4322
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4323 4324
	}

4325
	return selinux_netlbl_inet_conn_request(req, family);
4326 4327
}

4328 4329
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4330 4331 4332 4333
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4334
	newsksec->peer_sid = req->peer_secid;
4335 4336 4337 4338
	/* 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. */
4339

P
Paul Moore 已提交
4340 4341
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4342
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4343 4344
}

4345
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4346
{
4347
	u16 family = sk->sk_family;
4348 4349
	struct sk_security_struct *sksec = sk->sk_security;

4350 4351 4352 4353 4354
	/* 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);
4355 4356
}

4357 4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377
static int selinux_secmark_relabel_packet(u32 sid)
{
	const struct task_security_struct *__tsec;
	u32 tsid;

	__tsec = current_security();
	tsid = __tsec->sid;

	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
}

static void selinux_secmark_refcount_inc(void)
{
	atomic_inc(&selinux_secmark_refcount);
}

static void selinux_secmark_refcount_dec(void)
{
	atomic_dec(&selinux_secmark_refcount);
}

4378 4379
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4380
{
4381
	fl->flowi_secid = req->secid;
4382 4383
}

4384 4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

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

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

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

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

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

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

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

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

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4437 4438 4439 4440 4441
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4442
	struct sk_security_struct *sksec = sk->sk_security;
4443

L
Linus Torvalds 已提交
4444 4445 4446 4447
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4448
	nlh = nlmsg_hdr(skb);
4449

4450
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4451 4452
	if (err) {
		if (err == -EINVAL) {
4453
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4454 4455
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4456
				  nlh->nlmsg_type, sksec->sclass);
4457
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4458 4459 4460 4461 4462 4463 4464 4465 4466
				err = 0;
		}

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

4467
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4468 4469 4470 4471 4472 4473
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4474 4475
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4476
{
4477
	int err;
4478 4479
	char *addrp;
	u32 peer_sid;
4480
	struct common_audit_data ad;
4481
	u8 secmark_active;
4482
	u8 netlbl_active;
4483
	u8 peerlbl_active;
4484

4485 4486
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4487

4488
	secmark_active = selinux_secmark_enabled();
4489 4490
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4491 4492
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4493

4494 4495 4496
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4497
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4498 4499 4500 4501 4502
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4503 4504 4505 4506 4507
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4508
			return NF_DROP;
4509 4510
		}
	}
4511 4512 4513 4514 4515 4516

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

4517 4518 4519 4520 4521 4522 4523 4524
	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;

4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547
	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 */

4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578
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);
}

4579 4580
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4581
						u16 family)
4582 4583 4584
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4585
	struct common_audit_data ad;
4586 4587
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4588

4589 4590 4591 4592
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4593
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4594 4595 4596 4597 4598
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4599
	if (selinux_secmark_enabled())
4600
		if (avc_has_perm(sksec->sid, skb->secmark,
4601
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4602
			return NF_DROP_ERR(-ECONNREFUSED);
4603

4604 4605
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4606 4607

	return NF_ACCEPT;
4608 4609
}

4610 4611
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4612
{
4613 4614
	u32 secmark_perm;
	u32 peer_sid;
4615
	struct sock *sk;
4616
	struct common_audit_data ad;
4617 4618 4619
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4620

4621 4622 4623 4624
	/* 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. */
4625
	if (!selinux_policycap_netpeer)
4626
		return selinux_ip_postroute_compat(skb, ifindex, family);
4627
#ifdef CONFIG_XFRM
4628 4629 4630 4631 4632 4633
	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
	 *       is NULL, in this case go ahead and apply access control. */
E
Eric Dumazet 已提交
4634
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4635
		return NF_ACCEPT;
4636
#endif
4637 4638 4639 4640 4641
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4642 4643 4644 4645
	/* 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 */
4646
	sk = skb->sk;
4647
	if (sk == NULL) {
4648 4649
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4650
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4651
				return NF_DROP;
4652 4653
		} else {
			secmark_perm = PACKET__SEND;
4654
			peer_sid = SECINITSID_KERNEL;
4655
		}
4656
	} else {
4657 4658 4659 4660
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4661

4662
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4663 4664 4665
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4666
		return NF_DROP;
4667

4668 4669 4670
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4671
			return NF_DROP_ERR(-ECONNREFUSED);
4672 4673 4674 4675 4676 4677

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4678
			return NF_DROP;
4679 4680
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4681
			return NF_DROP_ERR(-ECONNREFUSED);
4682 4683

		if (sel_netnode_sid(addrp, family, &node_sid))
4684
			return NF_DROP;
4685 4686
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4687
			return NF_DROP_ERR(-ECONNREFUSED);
4688
	}
4689

4690
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4691 4692
}

4693 4694 4695 4696 4697
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
4698
{
4699
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4700 4701 4702
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4703 4704 4705 4706 4707
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
4708
{
4709
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4710 4711 4712 4713 4714 4715 4716 4717 4718
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4719
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4720 4721 4722
	if (err)
		return err;

4723
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4724 4725
}

4726
static int selinux_netlink_recv(struct sk_buff *skb, int capability)
L
Linus Torvalds 已提交
4727
{
4728
	int err;
4729
	struct common_audit_data ad;
4730
	u32 sid;
4731

4732
	err = cap_netlink_recv(skb, capability);
4733 4734 4735
	if (err)
		return err;

4736
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
4737 4738
	ad.u.cap = capability;

4739 4740 4741
	security_task_getsecid(current, &sid);
	return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
			    CAP_TO_MASK(capability), &ad);
L
Linus Torvalds 已提交
4742 4743 4744 4745 4746 4747 4748
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4749
	u32 sid;
L
Linus Torvalds 已提交
4750

J
James Morris 已提交
4751
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4752 4753 4754
	if (!isec)
		return -ENOMEM;

4755
	sid = task_sid(task);
L
Linus Torvalds 已提交
4756
	isec->sclass = sclass;
4757
	isec->sid = sid;
L
Linus Torvalds 已提交
4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773
	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
4774
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792
	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,
4793
			u32 perms)
L
Linus Torvalds 已提交
4794 4795
{
	struct ipc_security_struct *isec;
4796
	struct common_audit_data ad;
4797
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4798 4799 4800

	isec = ipc_perms->security;

4801
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4802 4803
	ad.u.ipc_id = ipc_perms->key;

4804
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820
}

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;
4821
	struct common_audit_data ad;
4822
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4823 4824 4825 4826 4827 4828 4829 4830
	int rc;

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

	isec = msq->q_perm.security;

4831
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4833

4834
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850
			  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;
4851
	struct common_audit_data ad;
4852
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4853 4854 4855

	isec = msq->q_perm.security;

4856
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4857 4858
	ad.u.ipc_id = msq->q_perm.key;

4859
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4860 4861 4862 4863 4864 4865 4866 4867
			    MSGQ__ASSOCIATE, &ad);
}

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

4868
	switch (cmd) {
L
Linus Torvalds 已提交
4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886
	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;
	}

4887
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4888 4889 4890 4891 4892 4893 4894
	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;
4895
	struct common_audit_data ad;
4896
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909
	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
		 */
4910
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4912 4913 4914 4915
		if (rc)
			return rc;
	}

4916
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4917 4918 4919
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4920
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4921 4922 4923
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4924 4925
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4926 4927
	if (!rc)
		/* Can the message be put in the queue? */
4928 4929
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4930 4931 4932 4933 4934 4935 4936 4937 4938 4939

	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;
4940
	struct common_audit_data ad;
4941
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4942 4943 4944 4945 4946
	int rc;

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

4947
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4949

4950
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4951 4952
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4953
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4954 4955 4956 4957 4958 4959 4960 4961
				  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;
4962
	struct common_audit_data ad;
4963
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4964 4965 4966 4967 4968 4969 4970 4971
	int rc;

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

	isec = shp->shm_perm.security;

4972
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4974

4975
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4976 4977 4978 4979 4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991
			  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;
4992
	struct common_audit_data ad;
4993
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4994 4995 4996

	isec = shp->shm_perm.security;

4997
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
4998 4999
	ad.u.ipc_id = shp->shm_perm.key;

5000
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5001 5002 5003 5004 5005 5006 5007 5008 5009
			    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;

5010
	switch (cmd) {
L
Linus Torvalds 已提交
5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032
	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;
	}

5033
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046
	return err;
}

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

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

5047
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5048 5049 5050 5051 5052 5053
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5054
	struct common_audit_data ad;
5055
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5056 5057 5058 5059 5060 5061 5062 5063
	int rc;

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

	isec = sma->sem_perm.security;

5064
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5066

5067
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083
			  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;
5084
	struct common_audit_data ad;
5085
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5086 5087 5088

	isec = sma->sem_perm.security;

5089
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
L
Linus Torvalds 已提交
5090 5091
	ad.u.ipc_id = sma->sem_perm.key;

5092
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5093 5094 5095 5096 5097 5098 5099 5100 5101
			    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;

5102
	switch (cmd) {
L
Linus Torvalds 已提交
5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133
	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;
	}

5134
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147
	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;

5148
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163
}

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;

5164
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5165 5166
}

5167 5168 5169 5170 5171 5172
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5173
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5174 5175 5176 5177 5178 5179
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5180
			       char *name, char **value)
L
Linus Torvalds 已提交
5181
{
5182
	const struct task_security_struct *__tsec;
5183
	u32 sid;
L
Linus Torvalds 已提交
5184
	int error;
5185
	unsigned len;
L
Linus Torvalds 已提交
5186 5187

	if (current != p) {
5188
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5189 5190 5191 5192
		if (error)
			return error;
	}

5193 5194
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5195 5196

	if (!strcmp(name, "current"))
5197
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5198
	else if (!strcmp(name, "prev"))
5199
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5200
	else if (!strcmp(name, "exec"))
5201
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5202
	else if (!strcmp(name, "fscreate"))
5203
		sid = __tsec->create_sid;
5204
	else if (!strcmp(name, "keycreate"))
5205
		sid = __tsec->keycreate_sid;
5206
	else if (!strcmp(name, "sockcreate"))
5207
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5208
	else
5209 5210
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5211 5212 5213 5214

	if (!sid)
		return 0;

5215 5216 5217 5218
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5219 5220 5221 5222

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5223 5224 5225 5226 5227 5228
}

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
5229
	struct task_struct *tracer;
D
David Howells 已提交
5230 5231
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246
	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"))
5247
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5248
	else if (!strcmp(name, "fscreate"))
5249
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5250
	else if (!strcmp(name, "keycreate"))
5251
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252
	else if (!strcmp(name, "sockcreate"))
5253
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5254
	else if (!strcmp(name, "current"))
5255
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267
	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);
5268 5269 5270 5271 5272 5273
		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
5274 5275 5276 5277
		if (error)
			return error;
	}

D
David Howells 已提交
5278 5279 5280 5281
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5282 5283 5284
	/* 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
5285
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5286 5287
	   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
5288 5289
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5290
		tsec->exec_sid = sid;
D
David Howells 已提交
5291
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5292
		tsec->create_sid = sid;
D
David Howells 已提交
5293
	} else if (!strcmp(name, "keycreate")) {
5294 5295
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5296
			goto abort_change;
5297
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5298
	} else if (!strcmp(name, "sockcreate")) {
5299
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5300 5301
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5302
		if (sid == 0)
D
David Howells 已提交
5303 5304 5305 5306
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5307
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5308 5309 5310
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5311
		}
L
Linus Torvalds 已提交
5312 5313 5314

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5316
		if (error)
D
David Howells 已提交
5317
			goto abort_change;
L
Linus Torvalds 已提交
5318 5319 5320

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5321
		ptsid = 0;
L
Linus Torvalds 已提交
5322
		task_lock(p);
5323
		tracer = ptrace_parent(p);
D
David Howells 已提交
5324 5325 5326 5327 5328 5329 5330
		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
5331
			if (error)
D
David Howells 已提交
5332
				goto abort_change;
L
Linus Torvalds 已提交
5333 5334
		}

D
David Howells 已提交
5335 5336 5337 5338 5339 5340 5341
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5342
	return size;
D
David Howells 已提交
5343 5344 5345 5346

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5347 5348
}

5349 5350 5351 5352 5353
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5354
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355 5356 5357 5358
{
	return security_context_to_sid(secdata, seclen, secid);
}

5359 5360
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5361
	kfree(secdata);
5362 5363
}

5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389
/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
}

/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
}

static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
	int len = 0;
	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
						ctx, true);
	if (len < 0)
		return len;
	*ctxlen = len;
	return 0;
}
5390 5391
#ifdef CONFIG_KEYS

D
David Howells 已提交
5392
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393
			     unsigned long flags)
5394
{
D
David Howells 已提交
5395
	const struct task_security_struct *tsec;
5396 5397 5398 5399 5400 5401
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5402 5403 5404
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5405
	else
D
David Howells 已提交
5406
		ksec->sid = tsec->sid;
5407

5408
	k->security = ksec;
5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420
	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
5421 5422
				  const struct cred *cred,
				  key_perm_t perm)
5423 5424 5425
{
	struct key *key;
	struct key_security_struct *ksec;
5426
	u32 sid;
5427 5428 5429 5430 5431 5432 5433

	/* 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
5434
	sid = cred_sid(cred);
5435 5436 5437 5438 5439

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440 5441
}

5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455
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;
}

5456 5457
#endif

L
Linus Torvalds 已提交
5458
static struct security_operations selinux_ops = {
5459 5460
	.name =				"selinux",

5461
	.ptrace_access_check =		selinux_ptrace_access_check,
5462
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5463
	.capget =			selinux_capget,
D
David Howells 已提交
5464
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5465 5466 5467 5468 5469 5470 5471
	.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,
5472
	.netlink_recv =			selinux_netlink_recv,
L
Linus Torvalds 已提交
5473

5474 5475 5476
	.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
5477 5478 5479 5480 5481
	.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,
5482
	.sb_remount =			selinux_sb_remount,
5483
	.sb_kern_mount =		selinux_sb_kern_mount,
5484
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5485 5486 5487
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5488
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5489
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5490 5491
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5492 5493 5494

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5495
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513
	.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,
5514 5515 5516
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5517
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530

	.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,

5531
	.dentry_open =			selinux_dentry_open,
5532

L
Linus Torvalds 已提交
5533
	.task_create =			selinux_task_create,
5534
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5535
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5536
	.cred_prepare =			selinux_cred_prepare,
5537
	.cred_transfer =		selinux_cred_transfer,
5538 5539
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5540
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5541 5542
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5543
	.task_getsid =			selinux_task_getsid,
5544
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5545
	.task_setnice =			selinux_task_setnice,
5546
	.task_setioprio =		selinux_task_setioprio,
5547
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5548 5549 5550
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5551
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5552 5553
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5554
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5555 5556

	.ipc_permission =		selinux_ipc_permission,
5557
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574

	.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,

5575 5576
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5577 5578 5579 5580
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5581
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5582

5583 5584
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5585

5586
	.secid_to_secctx =		selinux_secid_to_secctx,
5587
	.secctx_to_secid =		selinux_secctx_to_secid,
5588
	.release_secctx =		selinux_release_secctx,
5589 5590 5591
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5592

5593
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609
	.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
5610 5611
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5612 5613
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5614
	.sk_clone_security =		selinux_sk_clone_security,
5615
	.sk_getsecid =			selinux_sk_getsecid,
5616 5617 5618
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5619
	.inet_conn_established =	selinux_inet_conn_established,
5620 5621 5622
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5623
	.req_classify_flow =		selinux_req_classify_flow,
5624 5625 5626
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5627 5628 5629 5630 5631

#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
5632
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5633 5634
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5635
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5636
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5637 5638
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5639
#endif
5640 5641

#ifdef CONFIG_KEYS
5642 5643 5644
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5645
	.key_getsecurity =		selinux_key_getsecurity,
5646
#endif
5647 5648 5649 5650 5651 5652 5653

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
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5654 5655 5656 5657
};

static __init int selinux_init(void)
{
5658 5659 5660 5661 5662
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
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5663 5664 5665 5666 5667 5668 5669 5670
	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
5671
	cred_init_security();
L
Linus Torvalds 已提交
5672

5673 5674
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5675 5676
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5677
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5678 5679
	avc_init();

5680
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5681 5682
		panic("SELinux: Unable to register with kernel.\n");

5683
	if (selinux_enforcing)
5684
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5685
	else
5686
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5687

L
Linus Torvalds 已提交
5688 5689 5690
	return 0;
}

5691 5692 5693 5694 5695
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5696 5697
void selinux_complete_init(void)
{
5698
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5699 5700

	/* Set up any superblocks initialized prior to the policy load. */
5701
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5702
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5703 5704 5705 5706 5707 5708
}

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

5709
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5710

5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724
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,
5725 5726 5727 5728 5729 5730 5731
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5732
	}
L
Linus Torvalds 已提交
5733 5734 5735 5736
};

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

5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751
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
5752 5753 5754 5755 5756 5757 5758 5759 5760 5761
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5762 5763 5764

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

5765 5766 5767
	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
5768 5769

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5770 5771 5772
	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
5773
#endif	/* IPV6 */
5774

L
Linus Torvalds 已提交
5775 5776 5777 5778 5779 5780 5781 5782 5783
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5784
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5785

5786
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5787
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5788
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5789 5790 5791 5792
#endif	/* IPV6 */
}
#endif

5793
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5794 5795 5796 5797 5798

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5799
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5800 5801

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5802 5803
static int selinux_disabled;

L
Linus Torvalds 已提交
5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819 5820
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;
5821
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5822

5823
	reset_security_ops();
L
Linus Torvalds 已提交
5824

5825 5826 5827
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5828 5829 5830 5831 5832 5833 5834 5835 5836
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif