hooks.c 142.6 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#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 <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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#define NUM_SEL_MNT_OPTS 5
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	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
578 579
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
580
		goto out;
581
	}
L
Linus Torvalds 已提交
582

583 584 585 586 587 588 589 590 591 592 593
	/*
	 * 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)
	 */
594
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
595
	    && (num_opts == 0))
596
		goto out;
597

598 599 600 601 602 603 604
	/*
	 * 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;
605 606 607

		if (flags[i] == SE_SBLABELSUPP)
			continue;
608 609
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
610 611 612
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657
			       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
658
		}
659 660
	}

661
	if (sbsec->flags & SE_SBINITIALIZED) {
662
		/* previously mounted with options, but not on this attempt? */
663
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
664 665 666 667 668
			goto out_double_mount;
		rc = 0;
		goto out;
	}

669
	if (strcmp(sb->s_type->name, "proc") == 0)
670
		sbsec->flags |= SE_SBPROC;
671 672

	/* Determine the labeling behavior to use for this filesystem type. */
673
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
674 675
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
676
		       __func__, sb->s_type->name, rc);
677 678
		goto out;
	}
L
Linus Torvalds 已提交
679

680 681
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
682
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
683
		if (rc)
684
			goto out;
L
Linus Torvalds 已提交
685

686
		sbsec->sid = fscontext_sid;
687 688 689 690 691 692 693
	}

	/*
	 * 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.
	 */
694 695
	if (context_sid) {
		if (!fscontext_sid) {
696 697
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
698
			if (rc)
699 700
				goto out;
			sbsec->sid = context_sid;
701
		} else {
702 703
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
704
			if (rc)
705
				goto out;
706
		}
707 708
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
709

710
		sbsec->mntpoint_sid = context_sid;
711
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
712 713
	}

714
	if (rootcontext_sid) {
715 716
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
717
		if (rc)
718
			goto out;
719

720 721
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
722 723
	}

724 725 726 727 728 729
	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
730 731
		}

732 733
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
734
							     sbsec, cred);
735 736 737
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
738

739
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
740 741
	}

742
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
743
out:
744
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
745
	return rc;
746 747 748 749 750
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
751 752
}

753 754
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
755
{
756 757
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
758

759 760 761
	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
762

763 764
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
765
	 * mount options.  thus we can safely deal with this superblock later
766
	 */
767
	if (!ss_initialized)
768
		return;
769 770

	/* how can we clone if the old one wasn't set up?? */
771
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
772

773
	/* if fs is reusing a sb, just let its options stand... */
774
	if (newsbsec->flags & SE_SBINITIALIZED)
775 776
		return;

777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795
	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
796
	}
797 798 799 800 801
	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
802

803
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
804 805
	}

806 807 808 809
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

810 811
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
812
{
813
	char *p;
814 815
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
816
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
817

818
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
819

820 821 822 823
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
824

825 826
		if (!*p)
			continue;
L
Linus Torvalds 已提交
827

828
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
829

830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
		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;
882 883
		case Opt_labelsupport:
			break;
884 885 886 887
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
888 889 890

		}
	}
891

892 893 894 895 896 897 898 899 900 901 902
	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;
	}

903
	if (fscontext) {
904 905
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
906 907
	}
	if (context) {
908 909
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
910 911
	}
	if (rootcontext) {
912 913
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
914 915
	}
	if (defcontext) {
916 917
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
918 919
	}

920 921 922
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

923 924 925 926 927
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
928 929
	return rc;
}
930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956
/*
 * 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
957

A
Adrian Bunk 已提交
958 959
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
960 961 962 963 964
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
965 966 967 968 969 970
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
971 972 973 974 975 976 977 978 979 980 981 982 983 984

		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;
985 986 987 988
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
989 990
		default:
			BUG();
991
			return;
992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009
		};
		/* 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);
1010 1011 1012 1013
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1014
		return rc;
1015
	}
1016 1017 1018 1019 1020 1021 1022 1023

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046
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;
}

1047 1048 1049 1050 1051 1052 1053 1054 1055 1056
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
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072
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:
1073 1074 1075 1076
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1077
		case SOCK_DGRAM:
1078 1079 1080 1081
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1082 1083
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1084
		default:
L
Linus Torvalds 已提交
1085 1086 1087 1088 1089 1090 1091 1092 1093
			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;
1094
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107
			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;
1108 1109
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1110 1111 1112 1113 1114 1115 1116
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1117 1118
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1119 1120 1121 1122 1123 1124
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1125
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1126 1127 1128
				u16 tclass,
				u32 *sid)
{
1129 1130
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1131

1132
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1133 1134 1135
	if (!buffer)
		return -ENOMEM;

1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147
	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
1148 1149 1150 1151 1152
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1153
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175
				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;

1176
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1177
	if (isec->initialized)
1178
		goto out_unlock;
L
Linus Torvalds 已提交
1179 1180

	sbsec = inode->i_sb->s_security;
1181
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
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1182 1183 1184 1185 1186 1187 1188
		/* 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);
1189
		goto out_unlock;
L
Linus Torvalds 已提交
1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
	}

	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) {
1209 1210 1211 1212 1213 1214 1215 1216 1217
			/*
			 * 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.
			 */
1218
			goto out_unlock;
L
Linus Torvalds 已提交
1219 1220 1221
		}

		len = INITCONTEXTLEN;
1222
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1223 1224 1225
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1226
			goto out_unlock;
L
Linus Torvalds 已提交
1227
		}
1228
		context[len] = '\0';
L
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1229 1230 1231
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1232 1233
			kfree(context);

L
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1234 1235 1236 1237 1238
			/* 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);
1239
				goto out_unlock;
L
Linus Torvalds 已提交
1240 1241
			}
			len = rc;
1242
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1243 1244 1245
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1246
				goto out_unlock;
L
Linus Torvalds 已提交
1247
			}
1248
			context[len] = '\0';
L
Linus Torvalds 已提交
1249 1250 1251 1252 1253 1254 1255
			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
1256
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1257
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1258 1259
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1260
				goto out_unlock;
L
Linus Torvalds 已提交
1261 1262 1263 1264 1265
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1266
			rc = security_context_to_sid_default(context, rc, &sid,
1267 1268
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1269
			if (rc) {
1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
				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);
1301 1302
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1303
		if (rc)
1304
			goto out_unlock;
L
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1305 1306
		isec->sid = sid;
		break;
1307 1308 1309
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1310
	default:
1311
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1312 1313
		isec->sid = sbsec->sid;

1314
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1315
			if (opt_dentry) {
L
Linus Torvalds 已提交
1316
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1317
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1318 1319 1320
							  isec->sclass,
							  &sid);
				if (rc)
1321
					goto out_unlock;
L
Linus Torvalds 已提交
1322 1323 1324 1325 1326 1327 1328 1329
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1330 1331
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364
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
1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377
/*
 * 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);
}

1378
/*
1379
 * Check permission between a pair of tasks, e.g. signal checks,
1380 1381
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1382
 * - this uses the default subjective creds of tsk1
1383 1384 1385
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1386 1387
			 u32 perms)
{
1388 1389
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1390

1391 1392 1393 1394 1395
	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
1396 1397
}

1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413
/*
 * 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);
}

1414 1415 1416 1417
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1418
/* Check whether a task is allowed to use a capability. */
1419
static int cred_has_capability(const struct cred *cred,
1420
			       int cap, int audit)
L
Linus Torvalds 已提交
1421
{
1422
	struct common_audit_data ad;
1423
	struct av_decision avd;
1424
	u16 sclass;
1425
	u32 sid = cred_sid(cred);
1426
	u32 av = CAP_TO_MASK(cap);
1427
	int rc;
L
Linus Torvalds 已提交
1428

1429
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1430 1431
	ad.u.cap = cap;

1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442
	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();
1443
		return -EINVAL;
1444
	}
1445

1446
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1447 1448 1449 1450 1451
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1452
	return rc;
L
Linus Torvalds 已提交
1453 1454 1455 1456 1457 1458
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1459
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1460

1461
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1462 1463 1464 1465 1466 1467
			    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). */
1468
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1469 1470
			  struct inode *inode,
			  u32 perms,
1471 1472
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1473 1474
{
	struct inode_security_struct *isec;
1475
	u32 sid;
L
Linus Torvalds 已提交
1476

1477 1478
	validate_creds(cred);

1479
	if (unlikely(IS_PRIVATE(inode)))
1480 1481
		return 0;

1482
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1483 1484
	isec = inode->i_security;

1485
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1486 1487 1488 1489 1490
}

/* 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. */
1491
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1492 1493 1494 1495
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1496
	struct common_audit_data ad;
1497

1498
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
	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;

1513
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1514
	ad.u.path = *path;
1515
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1516 1517 1518 1519 1520 1521 1522 1523 1524 1525
}

/* 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. */
1526 1527 1528
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1529 1530
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1531
	struct inode *inode = file_inode(file);
1532
	struct common_audit_data ad;
1533
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1534 1535
	int rc;

1536
	ad.type = LSM_AUDIT_DATA_PATH;
1537
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1538

1539 1540
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1541 1542 1543 1544
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1545
			goto out;
L
Linus Torvalds 已提交
1546 1547 1548
	}

	/* av is zero if only checking access to the descriptor. */
1549
	rc = 0;
L
Linus Torvalds 已提交
1550
	if (av)
1551
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1552

1553 1554
out:
	return rc;
L
Linus Torvalds 已提交
1555 1556 1557 1558 1559 1560 1561
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1562
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1563 1564
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1565
	u32 sid, newsid;
1566
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1567 1568 1569 1570 1571
	int rc;

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

1572 1573 1574
	sid = tsec->sid;
	newsid = tsec->create_sid;

1575
	ad.type = LSM_AUDIT_DATA_DENTRY;
1576
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1577

1578
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1579 1580 1581 1582 1583
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1584
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1585 1586
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1587 1588 1589 1590
		if (rc)
			return rc;
	}

1591
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1592 1593 1594 1595 1596 1597 1598 1599
	if (rc)
		return rc;

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

1600 1601 1602 1603
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1604
	u32 sid = task_sid(ctx);
1605

1606
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1607 1608
}

1609 1610 1611
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1612 1613 1614 1615 1616 1617 1618 1619

/* 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;
1620
	struct common_audit_data ad;
1621
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1622 1623 1624 1625 1626 1627
	u32 av;
	int rc;

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

1628
	ad.type = LSM_AUDIT_DATA_DENTRY;
1629
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1630 1631 1632

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1633
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647
	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
1648 1649
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1650 1651 1652
		return 0;
	}

1653
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1654 1655 1656 1657 1658 1659 1660 1661 1662
	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;
1663
	struct common_audit_data ad;
1664
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1665 1666 1667 1668 1669 1670 1671 1672 1673
	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;

1674
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1675

1676
	ad.u.dentry = old_dentry;
1677
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1678 1679 1680
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1681
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1682 1683 1684 1685
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1686
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1687 1688 1689 1690 1691
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1692
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1693 1694 1695
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1696
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1697 1698 1699 1700 1701
	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);
1702
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1703 1704 1705 1706 1707 1708 1709 1710 1711 1712
				  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. */
1713
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1714 1715
			       struct super_block *sb,
			       u32 perms,
1716
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1717 1718
{
	struct superblock_security_struct *sbsec;
1719
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1720 1721

	sbsec = sb->s_security;
1722
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1723 1724 1725 1726 1727 1728 1729
}

/* 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;

A
Al Viro 已提交
1730
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752
		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;
}

1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775
/* 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
1776
/*
1777
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1778 1779
 * open permission.
 */
1780
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1781
{
1782
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1783

1784 1785 1786
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1787 1788 1789
	return av;
}

L
Linus Torvalds 已提交
1790 1791
/* Hook functions begin here. */

1792
static int selinux_ptrace_access_check(struct task_struct *child,
1793
				     unsigned int mode)
L
Linus Torvalds 已提交
1794 1795 1796
{
	int rc;

1797
	rc = cap_ptrace_access_check(child, mode);
L
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1798 1799 1800
	if (rc)
		return rc;

1801
	if (mode & PTRACE_MODE_READ) {
1802 1803 1804
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1805 1806
	}

1807
	return current_has_perm(child, PROCESS__PTRACE);
1808 1809 1810 1811 1812 1813
}

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

1814
	rc = cap_ptrace_traceme(parent);
1815 1816 1817 1818
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1819 1820 1821
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1822
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1823 1824 1825
{
	int error;

1826
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1827 1828 1829
	if (error)
		return error;

1830
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1831 1832
}

D
David Howells 已提交
1833 1834 1835 1836
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
1837 1838 1839
{
	int error;

1840
	error = cap_capset(new, old,
D
David Howells 已提交
1841
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1842 1843 1844
	if (error)
		return error;

D
David Howells 已提交
1845
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1846 1847
}

1848 1849 1850 1851 1852 1853 1854 1855 1856 1857
/*
 * (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.
 */

1858 1859
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1860 1861 1862
{
	int rc;

1863
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1864 1865 1866
	if (rc)
		return rc;

1867
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1868 1869 1870 1871
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1872
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1873 1874 1875 1876 1877 1878
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1879 1880 1881 1882 1883
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1884
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1885 1886 1887 1888
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1889
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1890 1891 1892 1893
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1894 1895 1896 1897 1898 1899
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1900 1901
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1902
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1903 1904
}

1905
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1906 1907 1908 1909
{
	int rc;

	switch (type) {
1910 1911
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1912 1913
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1914 1915 1916 1917
	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:
1918 1919
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1920 1921 1922 1923 1924
	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 */
1925 1926 1927
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939
	}
	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.
 */
1940
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1941 1942 1943
{
	int rc, cap_sys_admin = 0;

1944
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1945
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1946 1947 1948
	if (rc == 0)
		cap_sys_admin = 1;

1949
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1950 1951 1952 1953
}

/* binprm security operations */

1954
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1955
{
1956 1957
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1958
	struct inode_security_struct *isec;
1959
	struct common_audit_data ad;
A
Al Viro 已提交
1960
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
1961 1962
	int rc;

1963
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1964 1965 1966
	if (rc)
		return rc;

1967 1968 1969
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
1970 1971
		return 0;

1972 1973
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
1974 1975 1976
	isec = inode->i_security;

	/* Default to the current task SID. */
1977 1978
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
1979

1980
	/* Reset fs, key, and sock SIDs on execve. */
1981 1982 1983
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
1984

1985 1986
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
1987
		/* Reset exec SID on execve. */
1988
		new_tsec->exec_sid = 0;
1989 1990 1991 1992 1993 1994 1995

		/*
		 * Minimize confusion: if no_new_privs and a transition is
		 * explicitly requested, then fail the exec.
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
L
Linus Torvalds 已提交
1996 1997
	} else {
		/* Check for a default transition on this program. */
1998
		rc = security_transition_sid(old_tsec->sid, isec->sid,
1999 2000
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2001 2002 2003 2004
		if (rc)
			return rc;
	}

2005
	ad.type = LSM_AUDIT_DATA_PATH;
2006
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2007

2008 2009
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2010
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2011

2012 2013
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2014 2015 2016 2017 2018
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2019
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2020 2021 2022 2023
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2024
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2025 2026 2027 2028
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046
		/* 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();
2047
			tracer = ptrace_parent(current);
2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061
			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
2062

2063 2064
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2065 2066 2067 2068 2069
	}

	return 0;
}

2070
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2071
{
2072
	const struct task_security_struct *tsec = current_security();
2073
	u32 sid, osid;
L
Linus Torvalds 已提交
2074 2075
	int atsecure = 0;

2076 2077 2078 2079
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2080 2081 2082
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2083
		atsecure = avc_has_perm(osid, sid,
2084 2085
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2086 2087
	}

2088
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2089 2090
}

A
Al Viro 已提交
2091 2092 2093 2094 2095
static int match_file(const void *p, struct file *file, unsigned fd)
{
	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
}

L
Linus Torvalds 已提交
2096
/* Derived from fs/exec.c:flush_old_files. */
2097 2098
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2099 2100
{
	struct file *file, *devnull = NULL;
2101
	struct tty_struct *tty;
2102
	int drop_tty = 0;
A
Al Viro 已提交
2103
	unsigned n;
L
Linus Torvalds 已提交
2104

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

L
Linus Torvalds 已提交
2111
			/* Revalidate access to controlling tty.
2112
			   Use path_has_perm on the tty path directly rather
L
Linus Torvalds 已提交
2113 2114 2115
			   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
2116 2117 2118
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2119
			if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2120
				drop_tty = 1;
L
Linus Torvalds 已提交
2121
		}
N
Nick Piggin 已提交
2122
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2123
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2124
	}
2125 2126 2127
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2128 2129

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2130 2131 2132
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2133

A
Al Viro 已提交
2134
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2135 2136 2137 2138 2139 2140 2141
	if (IS_ERR(devnull))
		devnull = NULL;
	/* replace all the matching ones with this */
	do {
		replace_fd(n - 1, devnull, 0);
	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
	if (devnull)
A
Al Viro 已提交
2142
		fput(devnull);
L
Linus Torvalds 已提交
2143 2144
}

2145 2146 2147 2148
/*
 * 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
2149
{
2150 2151 2152
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2153

2154 2155 2156
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2157

2158 2159
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2160

2161 2162
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2163

2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
	/* 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) {
2177 2178
		/* protect against do_prlimit() */
		task_lock(current);
2179 2180 2181 2182
		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
2183
		}
2184 2185
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2186 2187 2188 2189
	}
}

/*
2190 2191
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2192
 */
2193
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2194
{
2195
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2196
	struct itimerval itimer;
2197
	u32 osid, sid;
L
Linus Torvalds 已提交
2198 2199
	int rc, i;

2200 2201 2202 2203
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2204 2205
		return;

2206 2207 2208 2209 2210 2211 2212 2213
	/* 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
2214 2215 2216 2217 2218
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2219 2220 2221 2222 2223
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2224 2225 2226
		spin_unlock_irq(&current->sighand->siglock);
	}

2227 2228
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2229
	read_lock(&tasklist_lock);
2230
	__wake_up_parent(current, current->real_parent);
2231
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255
}

/* 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)
{
2256 2257 2258
	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) ||
2259 2260
		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
2261 2262 2263 2264 2265 2266 2267
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2268
	} else
L
Linus Torvalds 已提交
2269 2270 2271 2272 2273
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2274 2275
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2276 2277 2278 2279 2280 2281
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2282
	} else
2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
		*first = 0;

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

2295
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2296 2297 2298 2299
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2300
	int open_quote = 0;
L
Linus Torvalds 已提交
2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315

	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 {
2316 2317 2318 2319
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2320 2321 2322
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2323
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2324 2325 2326 2327 2328 2329 2330
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2331
	strcpy(in_save, nosec_save);
2332
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2333 2334 2335 2336
out:
	return rc;
}

2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421
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;
}

2422
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2423
{
2424
	const struct cred *cred = current_cred();
2425
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2426 2427 2428 2429 2430 2431
	int rc;

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

2432 2433 2434 2435
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2436
	ad.type = LSM_AUDIT_DATA_DENTRY;
2437
	ad.u.dentry = sb->s_root;
2438
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2439 2440
}

2441
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2442
{
2443
	const struct cred *cred = current_cred();
2444
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2445

2446
	ad.type = LSM_AUDIT_DATA_DENTRY;
2447
	ad.u.dentry = dentry->d_sb->s_root;
2448
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2449 2450
}

A
Al Viro 已提交
2451
static int selinux_mount(const char *dev_name,
2452
			 struct path *path,
A
Al Viro 已提交
2453
			 const char *type,
2454 2455
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2456
{
2457
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2458 2459

	if (flags & MS_REMOUNT)
2460
		return superblock_has_perm(cred, path->dentry->d_sb,
2461
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2462
	else
E
Eric Paris 已提交
2463
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2464 2465 2466 2467
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2468
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2469

2470
	return superblock_has_perm(cred, mnt->mnt_sb,
2471
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485
}

/* 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);
}

2486
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2487 2488
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2489
{
2490
	const struct task_security_struct *tsec = current_security();
2491 2492
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2493
	u32 sid, newsid, clen;
2494
	int rc;
2495
	char *namep = NULL, *context;
2496 2497 2498 2499

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

2500 2501 2502
	sid = tsec->sid;
	newsid = tsec->create_sid;

2503 2504 2505 2506
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2507
		rc = security_transition_sid(sid, dsec->sid,
2508
					     inode_mode_to_security_class(inode->i_mode),
2509
					     qstr, &newsid);
2510 2511 2512 2513
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2514
			       __func__,
2515 2516 2517 2518 2519
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2520
	/* Possibly defer initialization to selinux_complete_init. */
2521
	if (sbsec->flags & SE_SBINITIALIZED) {
2522 2523 2524 2525 2526
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2527

2528
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2529 2530
		return -EOPNOTSUPP;

2531
	if (name) {
2532
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2533 2534 2535 2536
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2537

2538
	if (value && len) {
2539
		rc = security_sid_to_context_force(newsid, &context, &clen);
2540 2541 2542 2543 2544 2545
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2546 2547 2548 2549 2550
	}

	return 0;
}

A
Al Viro 已提交
2551
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570
{
	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);
}

2571
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2572 2573 2574 2575 2576 2577 2578 2579 2580
{
	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);
}

A
Al Viro 已提交
2581
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2582 2583 2584 2585 2586
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2587
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2588 2589 2590 2591 2592 2593
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2594 2595
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2596
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2597 2598 2599 2600
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2601
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2602

E
Eric Paris 已提交
2603
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2604 2605
}

2606 2607 2608
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2609
{
2610
	struct common_audit_data ad;
2611 2612 2613
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2614
	ad.type = LSM_AUDIT_DATA_INODE;
2615 2616 2617 2618 2619 2620 2621 2622 2623
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
			    audited, denied, &ad, flags);
	if (rc)
		return rc;
	return 0;
}

2624
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2625
{
2626
	const struct cred *cred = current_cred();
2627 2628
	u32 perms;
	bool from_access;
2629
	unsigned flags = mask & MAY_NOT_BLOCK;
2630 2631 2632 2633 2634
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2635

2636
	from_access = mask & MAY_ACCESS;
2637 2638
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2639 2640
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2641 2642
		return 0;

2643
	validate_creds(cred);
2644

2645 2646
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2647 2648 2649

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

2650 2651 2652 2653 2654 2655 2656 2657 2658 2659
	sid = cred_sid(cred);
	isec = inode->i_security;

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
	audited = avc_audit_required(perms, &avd, rc,
				     from_access ? FILE__AUDIT_ACCESS : 0,
				     &denied);
	if (likely(!audited))
		return rc;

2660
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2661 2662 2663
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2664 2665 2666 2667
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2668
	const struct cred *cred = current_cred();
2669
	unsigned int ia_valid = iattr->ia_valid;
2670
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2671

2672 2673 2674 2675 2676 2677 2678
	/* 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
2679

2680 2681
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2682
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2683

2684
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2685 2686 2687
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2688 2689 2690 2691
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2692
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2693 2694 2695 2696
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2697

E
Eric Paris 已提交
2698
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2699 2700
}

2701
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2702
{
2703 2704
	const struct cred *cred = current_cred();

2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718
	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
2719
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2720 2721
}

2722 2723
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
2724 2725 2726 2727
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2728
	struct common_audit_data ad;
2729
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2730 2731
	int rc = 0;

2732 2733
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2734 2735

	sbsec = inode->i_sb->s_security;
2736
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2737 2738
		return -EOPNOTSUPP;

2739
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2740 2741
		return -EPERM;

2742
	ad.type = LSM_AUDIT_DATA_DENTRY;
2743
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2744

2745
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2746 2747 2748 2749 2750
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2751
	if (rc == -EINVAL) {
2752 2753 2754 2755 2756 2757 2758
		if (!capable(CAP_MAC_ADMIN)) {
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
2759 2760 2761 2762 2763 2764 2765 2766 2767 2768
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2769 2770 2771 2772 2773
			ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
			audit_log_format(ab, "op=setxattr invalid_context=");
			audit_log_n_untrustedstring(ab, value, audit_size);
			audit_log_end(ab);

2774
			return rc;
2775
		}
2776 2777
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2778 2779 2780
	if (rc)
		return rc;

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

2786
	rc = security_validate_transition(isec->sid, newsid, sid,
2787
					  isec->sclass);
L
Linus Torvalds 已提交
2788 2789 2790 2791 2792 2793 2794 2795 2796 2797
	if (rc)
		return rc;

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

2798
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2799
					const void *value, size_t size,
2800
					int flags)
L
Linus Torvalds 已提交
2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811
{
	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;
	}

2812
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2813
	if (rc) {
2814 2815 2816
		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
2817 2818 2819 2820 2821 2822 2823
		return;
	}

	isec->sid = newsid;
	return;
}

2824
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2825
{
2826 2827
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2828
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2829 2830
}

2831
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2832
{
2833 2834
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2835
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2836 2837
}

2838
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2839
{
2840 2841
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2842 2843 2844 2845 2846 2847

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

2848
/*
2849
 * Copy the inode security context value to the user.
2850 2851 2852
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2853
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2854
{
2855 2856 2857
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2858
	struct inode_security_struct *isec = inode->i_security;
2859

2860 2861
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2862

2863 2864 2865 2866 2867 2868 2869 2870 2871
	/*
	 * 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.
	 */
2872
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2873
				SECURITY_CAP_NOAUDIT);
2874 2875 2876 2877 2878
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2879 2880 2881 2882 2883 2884 2885 2886 2887 2888
	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
2889 2890 2891
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2892
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903
{
	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;

2904
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2905 2906 2907 2908
	if (rc)
		return rc;

	isec->sid = newsid;
2909
	isec->initialized = 1;
L
Linus Torvalds 已提交
2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
	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;
}

2921 2922 2923 2924 2925 2926
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
2927 2928
/* file security operations */

2929
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2930
{
2931
	const struct cred *cred = current_cred();
A
Al Viro 已提交
2932
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
2933 2934 2935 2936 2937

	/* 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;

2938 2939
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2940 2941
}

2942 2943
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
2944
	struct inode *inode = file_inode(file);
2945 2946 2947 2948
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2949
	if (!mask)
2950 2951 2952
		/* No permission to check.  Existence test. */
		return 0;

2953 2954
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
2955
		/* No change since file_open check. */
2956 2957
		return 0;

2958 2959 2960
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973
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)
{
2974
	const struct cred *cred = current_cred();
2975
	int error = 0;
L
Linus Torvalds 已提交
2976

2977 2978 2979 2980 2981 2982 2983
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
2984
	case FS_IOC_GETFLAGS:
2985
	/* fall through */
2986
	case FS_IOC_GETVERSION:
2987 2988
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
2989

2990
	case FS_IOC_SETFLAGS:
2991
	/* fall through */
2992
	case FS_IOC_SETVERSION:
2993 2994 2995 2996 2997 2998 2999 3000 3001
		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
3002

3003 3004
	case KDSKBENT:
	case KDSKBSENT:
3005 3006
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3007 3008 3009 3010 3011 3012 3013 3014 3015
		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
3016 3017
}

3018 3019
static int default_noexec;

L
Linus Torvalds 已提交
3020 3021
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3022
	const struct cred *cred = current_cred();
D
David Howells 已提交
3023
	int rc = 0;
3024

3025 3026
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3027 3028 3029 3030 3031
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
D
David Howells 已提交
3032
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3033
		if (rc)
D
David Howells 已提交
3034
			goto error;
L
Linus Torvalds 已提交
3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047
	}

	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;

3048
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3049
	}
D
David Howells 已提交
3050 3051 3052

error:
	return rc;
L
Linus Torvalds 已提交
3053 3054
}

3055
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3056
{
3057
	int rc = 0;
3058
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3059

3060 3061 3062 3063 3064 3065
	/*
	 * 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.
	 */
3066
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3067 3068
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3069 3070 3071 3072 3073
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3074 3075
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3076

3077 3078 3079
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090
	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)
{
3091
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3092 3093 3094 3095

	if (selinux_checkreqprot)
		prot = reqprot;

3096 3097
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3098
		int rc = 0;
3099 3100
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3101
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3102 3103 3104
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3105
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3106 3107 3108 3109 3110 3111 3112 3113
		} 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
3114
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3115
		}
3116 3117 3118
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3119 3120 3121 3122 3123 3124

	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)
{
3125 3126 3127
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3128 3129 3130 3131 3132
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3133
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3134 3135 3136
	int err = 0;

	switch (cmd) {
3137 3138
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3139
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3140
			break;
3141 3142 3143 3144 3145 3146 3147
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3148
	case F_GETOWNER_UIDS:
3149
		/* Just check FD__USE permission */
3150
		err = file_has_perm(cred, file, 0);
3151 3152 3153 3154
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3155
#if BITS_PER_LONG == 32
3156 3157 3158
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3159
#endif
3160
		err = file_has_perm(cred, file, FILE__LOCK);
3161
		break;
L
Linus Torvalds 已提交
3162 3163 3164 3165 3166 3167 3168 3169 3170 3171
	}

	return err;
}

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

	fsec = file->f_security;
3172
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3173 3174 3175 3176 3177 3178 3179

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3180
	struct file *file;
3181
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3182 3183 3184 3185
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3186
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3187 3188 3189 3190 3191 3192 3193 3194

	fsec = file->f_security;

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

3195
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3196 3197 3198 3199 3200
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3201 3202 3203
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3204 3205
}

3206
static int selinux_file_open(struct file *file, const struct cred *cred)
3207 3208 3209
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3210

3211
	fsec = file->f_security;
A
Al Viro 已提交
3212
	isec = file_inode(file)->i_security;
3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229
	/*
	 * 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.
	 */
3230
	return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3231 3232
}

L
Linus Torvalds 已提交
3233 3234 3235 3236
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3237
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3238 3239
}

3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254
/*
 * 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
3255 3256 3257 3258
/*
 * 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
3259
{
D
David Howells 已提交
3260
	struct task_security_struct *tsec = cred->security;
3261

3262 3263 3264 3265 3266
	/*
	 * 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);
3267
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3268 3269
	kfree(tsec);
}
L
Linus Torvalds 已提交
3270

D
David Howells 已提交
3271 3272 3273 3274 3275 3276 3277 3278
/*
 * 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
3279

D
David Howells 已提交
3280
	old_tsec = old->security;
L
Linus Torvalds 已提交
3281

D
David Howells 已提交
3282 3283 3284
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3285

D
David Howells 已提交
3286
	new->security = tsec;
L
Linus Torvalds 已提交
3287 3288 3289
	return 0;
}

3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300
/*
 * 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;
}

3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341
/*
 * 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;
3342
	return ret;
3343 3344
}

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

	sid = task_sid(current);

3352
	ad.type = LSM_AUDIT_DATA_KMOD;
3353 3354 3355 3356
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3357 3358
}

L
Linus Torvalds 已提交
3359 3360
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3361
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3362 3363 3364 3365
}

static int selinux_task_getpgid(struct task_struct *p)
{
3366
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3367 3368 3369 3370
}

static int selinux_task_getsid(struct task_struct *p)
{
3371
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3372 3373
}

3374 3375
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3376
	*secid = task_sid(p);
3377 3378
}

L
Linus Torvalds 已提交
3379 3380 3381 3382
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3383
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3384 3385 3386
	if (rc)
		return rc;

3387
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3388 3389
}

3390 3391
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3392 3393
	int rc;

3394
	rc = cap_task_setioprio(p, ioprio);
3395 3396 3397
	if (rc)
		return rc;

3398
	return current_has_perm(p, PROCESS__SETSCHED);
3399 3400
}

3401 3402
static int selinux_task_getioprio(struct task_struct *p)
{
3403
	return current_has_perm(p, PROCESS__GETSCHED);
3404 3405
}

3406 3407
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3408
{
3409
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3410 3411 3412 3413

	/* 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
3414
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3415
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3416
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3417 3418 3419 3420

	return 0;
}

3421
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3422
{
3423 3424
	int rc;

3425
	rc = cap_task_setscheduler(p);
3426 3427 3428
	if (rc)
		return rc;

3429
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3430 3431 3432 3433
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3434
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3435 3436
}

3437 3438
static int selinux_task_movememory(struct task_struct *p)
{
3439
	return current_has_perm(p, PROCESS__SETSCHED);
3440 3441
}

3442 3443
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3444 3445 3446 3447 3448 3449 3450 3451
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3452
	if (secid)
3453 3454
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3455
	else
3456
		rc = current_has_perm(p, perm);
3457
	return rc;
L
Linus Torvalds 已提交
3458 3459 3460 3461
}

static int selinux_task_wait(struct task_struct *p)
{
3462
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3463 3464 3465 3466 3467 3468
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3469
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3470

3471
	isec->sid = sid;
L
Linus Torvalds 已提交
3472 3473 3474 3475
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3476
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3477
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3478 3479 3480 3481
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

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

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

3491 3492
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3493 3494
	ret = 0;

3495 3496 3497
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3498
	switch (ih->protocol) {
3499 3500
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3501

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

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

3510 3511
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3512
		break;
3513 3514 3515 3516 3517 3518 3519 3520
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3521
		offset += ihlen;
3522
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3523
		if (uh == NULL)
3524
			break;
L
Linus Torvalds 已提交
3525

3526 3527
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3528 3529
		break;
	}
L
Linus Torvalds 已提交
3530

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

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

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

3542 3543
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3544
		break;
3545
	}
J
James Morris 已提交
3546

3547 3548 3549
	default:
		break;
	}
L
Linus Torvalds 已提交
3550 3551 3552 3553 3554 3555 3556
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3557
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3558
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3559 3560 3561 3562
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3563
	__be16 frag_off;
L
Linus Torvalds 已提交
3564

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

3570 3571
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3572 3573 3574 3575
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3576
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3577 3578 3579
	if (offset < 0)
		goto out;

3580 3581 3582
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3583 3584
	switch (nexthdr) {
	case IPPROTO_TCP: {
3585
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3586 3587 3588 3589 3590

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

3591 3592
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3593 3594 3595 3596 3597 3598 3599 3600 3601 3602
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3603 3604
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3605 3606 3607
		break;
	}

J
James Morris 已提交
3608 3609 3610 3611 3612 3613 3614
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3615 3616
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3617
		break;
3618
	}
J
James Morris 已提交
3619

L
Linus Torvalds 已提交
3620 3621 3622 3623 3624 3625 3626 3627 3628 3629
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3630
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3631
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3632
{
3633 3634
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3635

3636
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3637
	case PF_INET:
3638
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3639 3640
		if (ret)
			goto parse_error;
3641 3642
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3643
		goto okay;
L
Linus Torvalds 已提交
3644 3645 3646

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3647
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3648 3649
		if (ret)
			goto parse_error;
3650 3651
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3652
		goto okay;
L
Linus Torvalds 已提交
3653 3654
#endif	/* IPV6 */
	default:
3655 3656
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3657 3658
	}

3659 3660 3661 3662
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3663
	return ret;
3664 3665 3666 3667 3668

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3669 3670
}

3671
/**
3672
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3673
 * @skb: the packet
3674
 * @family: protocol family
3675
 * @sid: the packet's peer label SID
3676 3677
 *
 * Description:
3678 3679 3680 3681 3682 3683
 * 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.
3684 3685
 *
 */
3686
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3687
{
3688
	int err;
3689 3690
	u32 xfrm_sid;
	u32 nlbl_sid;
3691
	u32 nlbl_type;
3692 3693

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3694
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3695

3696 3697 3698 3699 3700
	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");
3701
		return -EACCES;
3702
	}
3703 3704

	return 0;
3705 3706
}

L
Linus Torvalds 已提交
3707
/* socket security operations */
3708

3709 3710
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3711
{
3712 3713 3714 3715 3716 3717 3718
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3719 3720
}

3721
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3722
{
3723
	struct sk_security_struct *sksec = sk->sk_security;
3724
	struct common_audit_data ad;
3725
	struct lsm_network_audit net = {0,};
3726
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3727

3728 3729
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3730

3731
	ad.type = LSM_AUDIT_DATA_NET;
3732 3733
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3734

3735
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3736 3737 3738 3739 3740
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3741
	const struct task_security_struct *tsec = current_security();
3742
	u32 newsid;
3743
	u16 secclass;
3744
	int rc;
L
Linus Torvalds 已提交
3745 3746

	if (kern)
3747
		return 0;
3748 3749

	secclass = socket_type_to_security_class(family, type, protocol);
3750 3751 3752 3753
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3754
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3755 3756
}

V
Venkat Yekkirala 已提交
3757 3758
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3759
{
3760
	const struct task_security_struct *tsec = current_security();
3761
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3762
	struct sk_security_struct *sksec;
3763 3764
	int err = 0;

3765 3766
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3767 3768
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3769 3770 3771 3772 3773
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3774

L
Linus Torvalds 已提交
3775 3776
	isec->initialized = 1;

3777 3778 3779
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3780
		sksec->sclass = isec->sclass;
3781
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3782 3783
	}

V
Venkat Yekkirala 已提交
3784
	return err;
L
Linus Torvalds 已提交
3785 3786 3787 3788 3789 3790 3791 3792
}

/* 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)
{
3793
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3794 3795 3796
	u16 family;
	int err;

3797
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3798 3799 3800 3801 3802
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3803 3804
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3805
	 */
3806
	family = sk->sk_family;
L
Linus Torvalds 已提交
3807 3808
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3809
		struct sk_security_struct *sksec = sk->sk_security;
3810
		struct common_audit_data ad;
3811
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3812 3813 3814
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3815
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826

		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;
		}

3827 3828 3829 3830 3831 3832
		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
3833 3834
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3835 3836
				if (err)
					goto out;
3837
				ad.type = LSM_AUDIT_DATA_NET;
3838 3839 3840
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
3841 3842
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3843 3844 3845 3846
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3847
		}
3848

3849
		switch (sksec->sclass) {
3850
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3851 3852
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3853

3854
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3855 3856
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3857 3858 3859 3860 3861

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3862 3863 3864 3865
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3866

3867
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3868 3869
		if (err)
			goto out;
3870

3871
		ad.type = LSM_AUDIT_DATA_NET;
3872 3873 3874
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
3875 3876

		if (family == PF_INET)
3877
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
3878
		else
3879
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3880

3881 3882
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3883 3884 3885 3886 3887 3888 3889 3890 3891
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3892
	struct sock *sk = sock->sk;
3893
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3894 3895
	int err;

3896
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3897 3898 3899 3900
	if (err)
		return err;

	/*
J
James Morris 已提交
3901
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3902
	 */
3903 3904
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3905
		struct common_audit_data ad;
3906
		struct lsm_network_audit net = {0,};
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
		ad.type = LSM_AUDIT_DATA_NET;
3932 3933 3934
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
3935
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3936 3937 3938 3939
		if (err)
			goto out;
	}

3940 3941
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3942 3943 3944 3945 3946 3947
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3948
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3949 3950 3951 3952 3953 3954 3955 3956
}

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

3957
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971
	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,
3972
				  int size)
L
Linus Torvalds 已提交
3973
{
3974
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
3975 3976 3977 3978 3979
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
3980
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
3981 3982 3983 3984
}

static int selinux_socket_getsockname(struct socket *sock)
{
3985
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3986 3987 3988 3989
}

static int selinux_socket_getpeername(struct socket *sock)
{
3990
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
3991 3992
}

3993
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
3994
{
3995 3996
	int err;

3997
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3998 3999 4000 4001
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4002 4003 4004 4005 4006
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4007
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4008 4009 4010 4011
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4012
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4013 4014
}

4015 4016
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4017 4018
					      struct sock *newsk)
{
4019 4020
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4021
	struct sk_security_struct *sksec_new = newsk->sk_security;
4022
	struct common_audit_data ad;
4023
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4024 4025
	int err;

4026
	ad.type = LSM_AUDIT_DATA_NET;
4027 4028
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4029

4030 4031
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4032 4033 4034 4035 4036
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4037 4038 4039 4040 4041
	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;
4042

4043 4044 4045 4046
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4047 4048 4049 4050 4051
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4052 4053
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4054
	struct common_audit_data ad;
4055
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4056

4057
	ad.type = LSM_AUDIT_DATA_NET;
4058 4059
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4060

4061 4062
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4063 4064
}

4065 4066
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4067
				    struct common_audit_data *ad)
4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087
{
	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);
}

4088
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4089
				       u16 family)
4090
{
4091
	int err = 0;
4092 4093
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4094
	struct common_audit_data ad;
4095
	struct lsm_network_audit net = {0,};
4096 4097
	char *addrp;

4098
	ad.type = LSM_AUDIT_DATA_NET;
4099 4100 4101
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4102 4103 4104
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4105

4106
	if (selinux_secmark_enabled()) {
4107
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4108
				   PACKET__RECV, &ad);
4109 4110 4111
		if (err)
			return err;
	}
4112

4113 4114 4115 4116
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4117

4118 4119 4120 4121 4122
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4123
	int err;
4124
	struct sk_security_struct *sksec = sk->sk_security;
4125 4126
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4127
	struct common_audit_data ad;
4128
	struct lsm_network_audit net = {0,};
4129
	char *addrp;
4130 4131
	u8 secmark_active;
	u8 peerlbl_active;
4132 4133

	if (family != PF_INET && family != PF_INET6)
4134
		return 0;
4135 4136

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4137
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4138 4139
		family = PF_INET;

4140 4141 4142 4143
	/* 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. */
4144
	if (!selinux_policycap_netpeer)
4145 4146 4147 4148 4149 4150 4151
		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;

4152
	ad.type = LSM_AUDIT_DATA_NET;
4153 4154 4155
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4156
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4157
	if (err)
4158
		return err;
4159

4160
	if (peerlbl_active) {
4161 4162 4163
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4164 4165
		if (err)
			return err;
4166
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4167
					       peer_sid, &ad);
4168 4169
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4170
			return err;
4171
		}
4172 4173
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4174 4175
		if (err)
			selinux_netlbl_err(skb, err, 0);
4176 4177
	}

4178
	if (secmark_active) {
4179 4180 4181 4182 4183 4184
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4185
	return err;
L
Linus Torvalds 已提交
4186 4187
}

C
Catherine Zhang 已提交
4188 4189
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4190 4191 4192 4193
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4194
	struct sk_security_struct *sksec = sock->sk->sk_security;
4195
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4196

4197 4198
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4199
		peer_sid = sksec->peer_sid;
4200 4201
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4202

C
Catherine Zhang 已提交
4203
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4204
	if (err)
4205
		return err;
L
Linus Torvalds 已提交
4206 4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221

	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;
}

4222
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4223
{
4224
	u32 peer_secid = SECSID_NULL;
4225
	u16 family;
C
Catherine Zhang 已提交
4226

4227 4228 4229 4230 4231
	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)
4232 4233 4234 4235 4236
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4237
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4238
	else if (skb)
4239
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4240

4241
out:
4242
	*secid = peer_secid;
4243 4244 4245
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4246 4247
}

A
Al Viro 已提交
4248
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4249
{
4250 4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261
	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
4262 4263 4264 4265
}

static void selinux_sk_free_security(struct sock *sk)
{
4266 4267 4268 4269 4270
	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
4271 4272
}

4273
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4274
{
4275 4276
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4277

4278 4279 4280
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4281

4282
	selinux_netlbl_sk_security_reset(newsksec);
4283 4284
}

V
Venkat Yekkirala 已提交
4285
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4286
{
4287
	if (!sk)
V
Venkat Yekkirala 已提交
4288
		*secid = SECINITSID_ANY_SOCKET;
4289 4290
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4291

V
Venkat Yekkirala 已提交
4292
		*secid = sksec->sid;
4293
	}
4294 4295
}

4296
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4297 4298 4299 4300
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4301 4302 4303
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4304
	sksec->sclass = isec->sclass;
4305 4306
}

4307 4308
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4309 4310 4311
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4312
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4313
	u32 newsid;
4314 4315
	u32 peersid;

4316 4317 4318 4319 4320
	/* 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);
4321 4322
	if (err)
		return err;
4323 4324
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4325
		req->peer_secid = SECSID_NULL;
4326 4327 4328 4329 4330 4331
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4332 4333
	}

4334
	return selinux_netlbl_inet_conn_request(req, family);
4335 4336
}

4337 4338
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4339 4340 4341 4342
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4343
	newsksec->peer_sid = req->peer_secid;
4344 4345 4346 4347
	/* 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. */
4348

P
Paul Moore 已提交
4349 4350
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4351
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4352 4353
}

4354
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4355
{
4356
	u16 family = sk->sk_family;
4357 4358
	struct sk_security_struct *sksec = sk->sk_security;

4359 4360 4361 4362 4363
	/* 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);
4364 4365
}

4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386
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);
}

4387 4388
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4389
{
4390
	fl->flowi_secid = req->secid;
4391 4392
}

4393 4394 4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410
static int selinux_tun_dev_alloc_security(void **security)
{
	struct tun_security_struct *tunsec;

	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
	if (!tunsec)
		return -ENOMEM;
	tunsec->sid = current_sid();

	*security = tunsec;
	return 0;
}

static void selinux_tun_dev_free_security(void *security)
{
	kfree(security);
}

4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422 4423 4424 4425
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);
}

4426
static int selinux_tun_dev_attach_queue(void *security)
4427
{
4428 4429 4430 4431 4432 4433 4434 4435 4436
	struct tun_security_struct *tunsec = security;

	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
			    TUN_SOCKET__ATTACH_QUEUE, NULL);
}

static int selinux_tun_dev_attach(struct sock *sk, void *security)
{
	struct tun_security_struct *tunsec = security;
4437 4438 4439 4440 4441 4442 4443 4444 4445
	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 */

4446
	sksec->sid = tunsec->sid;
4447
	sksec->sclass = SECCLASS_TUN_SOCKET;
4448 4449

	return 0;
4450 4451
}

4452
static int selinux_tun_dev_open(void *security)
4453
{
4454
	struct tun_security_struct *tunsec = security;
4455 4456 4457
	u32 sid = current_sid();
	int err;

4458
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4459 4460 4461 4462 4463 4464 4465
			   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;
4466
	tunsec->sid = sid;
4467 4468 4469 4470

	return 0;
}

L
Linus Torvalds 已提交
4471 4472 4473 4474 4475
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4476
	struct sk_security_struct *sksec = sk->sk_security;
4477

L
Linus Torvalds 已提交
4478 4479 4480 4481
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4482
	nlh = nlmsg_hdr(skb);
4483

4484
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4485 4486
	if (err) {
		if (err == -EINVAL) {
4487
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4488 4489
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4490
				  nlh->nlmsg_type, sksec->sclass);
4491
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4492 4493 4494 4495 4496 4497 4498 4499 4500
				err = 0;
		}

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

4501
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4502 4503 4504 4505 4506 4507
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4508 4509
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4510
{
4511
	int err;
4512 4513
	char *addrp;
	u32 peer_sid;
4514
	struct common_audit_data ad;
4515
	struct lsm_network_audit net = {0,};
4516
	u8 secmark_active;
4517
	u8 netlbl_active;
4518
	u8 peerlbl_active;
4519

4520 4521
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4522

4523
	secmark_active = selinux_secmark_enabled();
4524 4525
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4526 4527
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4528

4529 4530 4531
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4532
	ad.type = LSM_AUDIT_DATA_NET;
4533 4534 4535
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4536 4537 4538
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4539 4540 4541 4542 4543
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4544
			return NF_DROP;
4545 4546
		}
	}
4547 4548 4549 4550 4551 4552

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

4553 4554 4555 4556 4557 4558 4559 4560
	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;

4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583
	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 */

4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614
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);
}

4615 4616
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4617
						u16 family)
4618 4619 4620
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4621
	struct common_audit_data ad;
4622
	struct lsm_network_audit net = {0,};
4623 4624
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4625

4626 4627 4628 4629
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4630
	ad.type = LSM_AUDIT_DATA_NET;
4631 4632 4633
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4634 4635 4636
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4637
	if (selinux_secmark_enabled())
4638
		if (avc_has_perm(sksec->sid, skb->secmark,
4639
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4640
			return NF_DROP_ERR(-ECONNREFUSED);
4641

4642 4643
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4644 4645

	return NF_ACCEPT;
4646 4647
}

4648 4649
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4650
{
4651 4652
	u32 secmark_perm;
	u32 peer_sid;
4653
	struct sock *sk;
4654
	struct common_audit_data ad;
4655
	struct lsm_network_audit net = {0,};
4656 4657 4658
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4659

4660 4661 4662 4663
	/* 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. */
4664
	if (!selinux_policycap_netpeer)
4665
		return selinux_ip_postroute_compat(skb, ifindex, family);
4666
#ifdef CONFIG_XFRM
4667 4668 4669 4670 4671 4672
	/* 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
4673
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4674
		return NF_ACCEPT;
4675
#endif
4676 4677 4678 4679 4680
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4681 4682 4683 4684
	/* 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 */
4685
	sk = skb->sk;
4686
	if (sk == NULL) {
4687 4688
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4689
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4690
				return NF_DROP;
4691 4692
		} else {
			secmark_perm = PACKET__SEND;
4693
			peer_sid = SECINITSID_KERNEL;
4694
		}
4695
	} else {
4696 4697 4698 4699
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4700

4701
	ad.type = LSM_AUDIT_DATA_NET;
4702 4703 4704
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4705
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4706
		return NF_DROP;
4707

4708 4709 4710
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4711
			return NF_DROP_ERR(-ECONNREFUSED);
4712 4713 4714 4715 4716 4717

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4718
			return NF_DROP;
4719 4720
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4721
			return NF_DROP_ERR(-ECONNREFUSED);
4722 4723

		if (sel_netnode_sid(addrp, family, &node_sid))
4724
			return NF_DROP;
4725 4726
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4727
			return NF_DROP_ERR(-ECONNREFUSED);
4728
	}
4729

4730
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4731 4732
}

4733 4734 4735 4736 4737
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
4738
{
4739
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4740 4741 4742
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4743 4744 4745 4746 4747
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
4748
{
4749
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4750 4751 4752 4753 4754 4755 4756 4757 4758
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4759
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4760 4761 4762
	if (err)
		return err;

4763
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4764 4765 4766 4767 4768 4769 4770
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4771
	u32 sid;
L
Linus Torvalds 已提交
4772

J
James Morris 已提交
4773
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4774 4775 4776
	if (!isec)
		return -ENOMEM;

4777
	sid = task_sid(task);
L
Linus Torvalds 已提交
4778
	isec->sclass = sclass;
4779
	isec->sid = sid;
L
Linus Torvalds 已提交
4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795
	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
4796
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814
	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,
4815
			u32 perms)
L
Linus Torvalds 已提交
4816 4817
{
	struct ipc_security_struct *isec;
4818
	struct common_audit_data ad;
4819
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4820 4821 4822

	isec = ipc_perms->security;

4823
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4824 4825
	ad.u.ipc_id = ipc_perms->key;

4826
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842
}

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;
4843
	struct common_audit_data ad;
4844
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4845 4846 4847 4848 4849 4850 4851 4852
	int rc;

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

	isec = msq->q_perm.security;

4853
	ad.type = LSM_AUDIT_DATA_IPC;
4854
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4855

4856
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872
			  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;
4873
	struct common_audit_data ad;
4874
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4875 4876 4877

	isec = msq->q_perm.security;

4878
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4879 4880
	ad.u.ipc_id = msq->q_perm.key;

4881
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4882 4883 4884 4885 4886 4887 4888 4889
			    MSGQ__ASSOCIATE, &ad);
}

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

4890
	switch (cmd) {
L
Linus Torvalds 已提交
4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908
	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;
	}

4909
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4910 4911 4912 4913 4914 4915 4916
	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;
4917
	struct common_audit_data ad;
4918
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931
	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
		 */
4932
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4933
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4934 4935 4936 4937
		if (rc)
			return rc;
	}

4938
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
4939 4940 4941
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4942
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4943 4944 4945
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4946 4947
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4948 4949
	if (!rc)
		/* Can the message be put in the queue? */
4950 4951
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4952 4953 4954 4955 4956 4957 4958 4959 4960 4961

	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;
4962
	struct common_audit_data ad;
4963
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4964 4965 4966 4967 4968
	int rc;

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

4969
	ad.type = LSM_AUDIT_DATA_IPC;
4970
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4971

4972
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4973 4974
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4975
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4976 4977 4978 4979 4980 4981 4982 4983
				  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;
4984
	struct common_audit_data ad;
4985
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4986 4987 4988 4989 4990 4991 4992 4993
	int rc;

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

	isec = shp->shm_perm.security;

4994
	ad.type = LSM_AUDIT_DATA_IPC;
4995
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
4996

4997
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013
			  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;
5014
	struct common_audit_data ad;
5015
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5016 5017 5018

	isec = shp->shm_perm.security;

5019
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5020 5021
	ad.u.ipc_id = shp->shm_perm.key;

5022
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5023 5024 5025 5026 5027 5028 5029 5030 5031
			    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;

5032
	switch (cmd) {
L
Linus Torvalds 已提交
5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054
	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;
	}

5055
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068
	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;

5069
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5070 5071 5072 5073 5074 5075
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5076
	struct common_audit_data ad;
5077
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5078 5079 5080 5081 5082 5083 5084 5085
	int rc;

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

	isec = sma->sem_perm.security;

5086
	ad.type = LSM_AUDIT_DATA_IPC;
5087
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5088

5089
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105
			  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;
5106
	struct common_audit_data ad;
5107
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5108 5109 5110

	isec = sma->sem_perm.security;

5111
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5112 5113
	ad.u.ipc_id = sma->sem_perm.key;

5114
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5115 5116 5117 5118 5119 5120 5121 5122 5123
			    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;

5124
	switch (cmd) {
L
Linus Torvalds 已提交
5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154 5155
	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;
	}

5156
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169
	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;

5170
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185
}

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;

5186
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5187 5188
}

5189 5190 5191 5192 5193 5194
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5195
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5196 5197 5198 5199 5200 5201
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5202
			       char *name, char **value)
L
Linus Torvalds 已提交
5203
{
5204
	const struct task_security_struct *__tsec;
5205
	u32 sid;
L
Linus Torvalds 已提交
5206
	int error;
5207
	unsigned len;
L
Linus Torvalds 已提交
5208 5209

	if (current != p) {
5210
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5211 5212 5213 5214
		if (error)
			return error;
	}

5215 5216
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5217 5218

	if (!strcmp(name, "current"))
5219
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5220
	else if (!strcmp(name, "prev"))
5221
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5222
	else if (!strcmp(name, "exec"))
5223
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5224
	else if (!strcmp(name, "fscreate"))
5225
		sid = __tsec->create_sid;
5226
	else if (!strcmp(name, "keycreate"))
5227
		sid = __tsec->keycreate_sid;
5228
	else if (!strcmp(name, "sockcreate"))
5229
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5230
	else
5231 5232
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5233 5234 5235 5236

	if (!sid)
		return 0;

5237 5238 5239 5240
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5241 5242 5243 5244

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5245 5246 5247 5248 5249 5250
}

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
5251
	struct task_struct *tracer;
D
David Howells 已提交
5252 5253
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268
	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"))
5269
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5270
	else if (!strcmp(name, "fscreate"))
5271
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5272
	else if (!strcmp(name, "keycreate"))
5273
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5274
	else if (!strcmp(name, "sockcreate"))
5275
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5276
	else if (!strcmp(name, "current"))
5277
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289
	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);
5290
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305
			if (!capable(CAP_MAC_ADMIN)) {
				struct audit_buffer *ab;
				size_t audit_size;

				/* We strip a nul only if it is at the end, otherwise the
				 * context contains a nul and we should audit that */
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
				ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
				audit_log_format(ab, "op=fscreate invalid_context=");
				audit_log_n_untrustedstring(ab, value, audit_size);
				audit_log_end(ab);

5306
				return error;
5307
			}
5308 5309 5310
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5311 5312 5313 5314
		if (error)
			return error;
	}

D
David Howells 已提交
5315 5316 5317 5318
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5319 5320 5321
	/* 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
5322
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5323 5324
	   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
5325 5326
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5327
		tsec->exec_sid = sid;
D
David Howells 已提交
5328
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5329
		tsec->create_sid = sid;
D
David Howells 已提交
5330
	} else if (!strcmp(name, "keycreate")) {
5331 5332
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5333
			goto abort_change;
5334
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5335
	} else if (!strcmp(name, "sockcreate")) {
5336
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5337 5338
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5339
		if (sid == 0)
D
David Howells 已提交
5340 5341 5342 5343
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5344
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5345 5346 5347
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5348
		}
L
Linus Torvalds 已提交
5349 5350 5351

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5352
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5353
		if (error)
D
David Howells 已提交
5354
			goto abort_change;
L
Linus Torvalds 已提交
5355 5356 5357

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5358
		ptsid = 0;
L
Linus Torvalds 已提交
5359
		task_lock(p);
5360
		tracer = ptrace_parent(p);
D
David Howells 已提交
5361 5362 5363 5364 5365 5366 5367
		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
5368
			if (error)
D
David Howells 已提交
5369
				goto abort_change;
L
Linus Torvalds 已提交
5370 5371
		}

D
David Howells 已提交
5372 5373 5374 5375 5376 5377 5378
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5379
	return size;
D
David Howells 已提交
5380 5381 5382 5383

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5384 5385
}

5386 5387 5388 5389 5390
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5391
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5392 5393 5394 5395
{
	return security_context_to_sid(secdata, seclen, secid);
}

5396 5397
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5398
	kfree(secdata);
5399 5400
}

5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426
/*
 *	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;
}
5427 5428
#ifdef CONFIG_KEYS

D
David Howells 已提交
5429
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5430
			     unsigned long flags)
5431
{
D
David Howells 已提交
5432
	const struct task_security_struct *tsec;
5433 5434 5435 5436 5437 5438
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5439 5440 5441
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5442
	else
D
David Howells 已提交
5443
		ksec->sid = tsec->sid;
5444

5445
	k->security = ksec;
5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457
	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
5458 5459
				  const struct cred *cred,
				  key_perm_t perm)
5460 5461 5462
{
	struct key *key;
	struct key_security_struct *ksec;
5463
	u32 sid;
5464 5465 5466 5467 5468 5469 5470

	/* 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
5471
	sid = cred_sid(cred);
5472 5473 5474 5475 5476

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5477 5478
}

5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492
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;
}

5493 5494
#endif

L
Linus Torvalds 已提交
5495
static struct security_operations selinux_ops = {
5496 5497
	.name =				"selinux",

5498
	.ptrace_access_check =		selinux_ptrace_access_check,
5499
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5500
	.capget =			selinux_capget,
D
David Howells 已提交
5501
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5502 5503 5504 5505 5506 5507 5508 5509
	.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,

5510 5511 5512
	.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
5513 5514 5515 5516 5517
	.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,
5518
	.sb_remount =			selinux_sb_remount,
5519
	.sb_kern_mount =		selinux_sb_kern_mount,
5520
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5521 5522 5523
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5524
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5525
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5526 5527
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5528 5529 5530

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5531
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549
	.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,
5550 5551 5552
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5553
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5554 5555 5556 5557 5558

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5559 5560
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5561 5562 5563 5564 5565 5566 5567
	.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,

5568
	.file_open =			selinux_file_open,
5569

L
Linus Torvalds 已提交
5570
	.task_create =			selinux_task_create,
5571
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5572
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5573
	.cred_prepare =			selinux_cred_prepare,
5574
	.cred_transfer =		selinux_cred_transfer,
5575 5576
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5577
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5578 5579
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5580
	.task_getsid =			selinux_task_getsid,
5581
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5582
	.task_setnice =			selinux_task_setnice,
5583
	.task_setioprio =		selinux_task_setioprio,
5584
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5585 5586 5587
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5588
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5589 5590
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5591
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5592 5593

	.ipc_permission =		selinux_ipc_permission,
5594
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611

	.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,

5612 5613
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5614 5615 5616 5617
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5618
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5619

5620 5621
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5622

5623
	.secid_to_secctx =		selinux_secid_to_secctx,
5624
	.secctx_to_secid =		selinux_secctx_to_secid,
5625
	.release_secctx =		selinux_release_secctx,
5626 5627 5628
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5629

5630
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646
	.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
5647 5648
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5649 5650
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5651
	.sk_clone_security =		selinux_sk_clone_security,
5652
	.sk_getsecid =			selinux_sk_getsecid,
5653 5654 5655
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5656
	.inet_conn_established =	selinux_inet_conn_established,
5657 5658 5659
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5660
	.req_classify_flow =		selinux_req_classify_flow,
5661 5662
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5663
	.tun_dev_create =		selinux_tun_dev_create,
5664
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5665
	.tun_dev_attach =		selinux_tun_dev_attach,
5666
	.tun_dev_open =			selinux_tun_dev_open,
5667 5668 5669 5670 5671

#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
5672
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5673 5674
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5675
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5676
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5677 5678
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5679
#endif
5680 5681

#ifdef CONFIG_KEYS
5682 5683 5684
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5685
	.key_getsecurity =		selinux_key_getsecurity,
5686
#endif
5687 5688 5689 5690 5691 5692 5693

#ifdef CONFIG_AUDIT
	.audit_rule_init =		selinux_audit_rule_init,
	.audit_rule_known =		selinux_audit_rule_known,
	.audit_rule_match =		selinux_audit_rule_match,
	.audit_rule_free =		selinux_audit_rule_free,
#endif
L
Linus Torvalds 已提交
5694 5695 5696 5697
};

static __init int selinux_init(void)
{
5698 5699 5700 5701 5702
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5703 5704 5705 5706 5707 5708 5709 5710
	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
5711
	cred_init_security();
L
Linus Torvalds 已提交
5712

5713 5714
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5715 5716
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5717
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5718 5719
	avc_init();

5720
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5721 5722
		panic("SELinux: Unable to register with kernel.\n");

5723
	if (selinux_enforcing)
5724
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5725
	else
5726
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5727

L
Linus Torvalds 已提交
5728 5729 5730
	return 0;
}

5731 5732 5733 5734 5735
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5736 5737
void selinux_complete_init(void)
{
5738
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5739 5740

	/* Set up any superblocks initialized prior to the policy load. */
5741
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5742
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5743 5744 5745 5746 5747 5748
}

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

5749
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5750

5751 5752 5753 5754
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5755
		.pf =		NFPROTO_IPV4,
5756 5757 5758 5759 5760 5761
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5762
		.pf =		NFPROTO_IPV4,
5763 5764
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5765 5766 5767 5768
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
5769
		.pf =		NFPROTO_IPV4,
5770 5771
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5772
	}
L
Linus Torvalds 已提交
5773 5774 5775 5776
};

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

5777 5778 5779 5780
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
5781
		.pf =		NFPROTO_IPV6,
5782 5783 5784 5785 5786 5787
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
5788
		.pf =		NFPROTO_IPV6,
5789 5790 5791
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5792 5793 5794 5795 5796 5797 5798 5799 5800 5801
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5802 5803 5804

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

5805 5806 5807
	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
5808 5809

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5810 5811 5812
	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
5813
#endif	/* IPV6 */
5814

L
Linus Torvalds 已提交
5815 5816 5817 5818 5819 5820 5821 5822 5823
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5824
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5825

5826
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5827
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5828
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5829 5830 5831 5832
#endif	/* IPV6 */
}
#endif

5833
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5834 5835 5836 5837 5838

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5839
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5840 5841

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5842 5843
static int selinux_disabled;

L
Linus Torvalds 已提交
5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858
int selinux_disable(void)
{
	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

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

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

	selinux_disabled = 1;
5859
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5860

5861
	reset_security_ops();
L
Linus Torvalds 已提交
5862

5863 5864 5865
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5866 5867 5868 5869 5870 5871 5872 5873 5874
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif