hooks.c 151.2 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/sock.h>
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#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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#include <net/inet_connection_sock.h>
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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 */
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#include <net/netlink.h>
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#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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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;
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	if (!kstrtoul(str, 0, &enforcing))
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		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;
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	if (!kstrtoul(str, 0, &enabled))
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		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
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 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 * policy capability is enabled, SECMARK is always considered enabled.
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 *
 */
static int selinux_secmark_enabled(void)
{
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	return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
}

/**
 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 *
 * Description:
 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 * (1) if any are enabled or false (0) if neither are enabled.  If the
 * always_check_network policy capability is enabled, peer labeling
 * is always considered enabled.
 *
 */
static int selinux_peerlbl_enabled(void)
{
	return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
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}

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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;
}

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static void inode_free_rcu(struct rcu_head *head)
{
	struct inode_security_struct *isec;

	isec = container_of(head, struct inode_security_struct, rcu);
	kmem_cache_free(sel_inode_cache, isec);
}

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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);

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	/*
	 * The inode may still be referenced in a path walk and
	 * a call to selinux_inode_permission() can be made
	 * after inode_free_security() is called. Ideally, the VFS
	 * wouldn't do this, but fixing that is a much harder
	 * job. For now, simply free the i_security via RCU, and
	 * leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&isec->rcu, inode_free_rcu);
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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[7] = {
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	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
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	"uses native labeling",
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};

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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	Opt_nextmntopt = 6,
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};

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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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 selinux_is_sblabel_mnt(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

	if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
	    sbsec->behavior == SECURITY_FS_USE_TRANS ||
	    sbsec->behavior == SECURITY_FS_USE_TASK)
		return 1;

	/* Special handling for sysfs. Is genfs but also has setxattr handler*/
	if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
		return 1;

	/*
	 * Special handling for rootfs. Is genfs but supports
	 * setting SELinux context on in-core inodes.
	 */
	if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
		return 1;

	return 0;
}

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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) {
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			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
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			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 "
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				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
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			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
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				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
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			goto out;
		}
	}
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	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
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		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
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	else
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		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
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		       labeling_behaviors[sbsec->behavior-1]);
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	sbsec->flags |= SE_SBINITIALIZED;
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	if (selinux_is_sblabel_mnt(sb))
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		sbsec->flags |= SBLABEL_MNT;
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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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	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

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	tmp = sbsec->flags & SE_MNTMASK;
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	/* count the number of mount options for this sb */
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	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
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		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 */
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	if (sbsec->flags & SBLABEL_MNT)
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		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;
566 567
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
568
	}
569
	if (sbsec->flags & SBLABEL_MNT) {
570
		opts->mnt_opts[i] = NULL;
571
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
572
	}
L
Linus Torvalds 已提交
573

574
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
575

576 577 578
	return 0;

out_free:
579
	security_free_mnt_opts(opts);
580 581
	return rc;
}
L
Linus Torvalds 已提交
582

583 584 585
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
586 587
	char mnt_flags = sbsec->flags & SE_MNTMASK;

588
	/* check if the old mount command had the same options */
589
	if (sbsec->flags & SE_SBINITIALIZED)
590 591 592 593 594 595 596
		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
	 */
597 598
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
599 600 601
			return 1;
	return 0;
}
602

603 604 605 606
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
607
static int selinux_set_mnt_opts(struct super_block *sb,
608 609 610
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
611
{
612
	const struct cred *cred = current_cred();
613 614
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
615
	const char *name = sb->s_type->name;
616 617
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
618 619
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
620 621 622
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
623 624 625 626 627 628 629 630 631 632 633

	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
634 635
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
636
		goto out;
637
	}
638 639 640 641 642 643
	if (kern_flags && !set_kern_flags) {
		/* Specifying internal flags without providing a place to
		 * place the results is not allowed */
		rc = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
644

645 646 647 648 649 650 651 652 653 654 655
	/*
	 * 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)
	 */
656
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
657
	    && (num_opts == 0))
658
		goto out;
659

660 661 662 663 664 665 666
	/*
	 * 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;
667

668
		if (flags[i] == SBLABEL_MNT)
669
			continue;
670
		rc = security_context_to_sid(mount_options[i],
671
					     strlen(mount_options[i]), &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
672 673
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
674 675
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719
			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
720
		}
721 722
	}

723
	if (sbsec->flags & SE_SBINITIALIZED) {
724
		/* previously mounted with options, but not on this attempt? */
725
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
726 727 728 729 730
			goto out_double_mount;
		rc = 0;
		goto out;
	}

731
	if (strcmp(sb->s_type->name, "proc") == 0)
732
		sbsec->flags |= SE_SBPROC;
733

734 735 736 737 738
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
739
		rc = security_fs_use(sb);
740 741 742 743 744 745
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
746 747 748
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
749
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
750
		if (rc)
751
			goto out;
L
Linus Torvalds 已提交
752

753
		sbsec->sid = fscontext_sid;
754 755 756 757 758 759 760
	}

	/*
	 * 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.
	 */
761 762 763 764 765
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

766 767
	if (context_sid) {
		if (!fscontext_sid) {
768 769
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
770
			if (rc)
771 772
				goto out;
			sbsec->sid = context_sid;
773
		} else {
774 775
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
776
			if (rc)
777
				goto out;
778
		}
779 780
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
781

782
		sbsec->mntpoint_sid = context_sid;
783
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
784 785
	}

786
	if (rootcontext_sid) {
787 788
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
789
		if (rc)
790
			goto out;
791

792 793
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
794 795
	}

796
	if (defcontext_sid) {
797 798
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
799 800 801 802
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
803 804
		}

805 806
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
807
							     sbsec, cred);
808 809 810
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
811

812
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
813 814
	}

815
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
816
out:
817
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
818
	return rc;
819 820 821
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
822
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
823
	goto out;
L
Linus Torvalds 已提交
824 825
}

826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856
static int selinux_cmp_sb_context(const struct super_block *oldsb,
				    const struct super_block *newsb)
{
	struct superblock_security_struct *old = oldsb->s_security;
	struct superblock_security_struct *new = newsb->s_security;
	char oldflags = old->flags & SE_MNTMASK;
	char newflags = new->flags & SE_MNTMASK;

	if (oldflags != newflags)
		goto mismatch;
	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
		goto mismatch;
	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
		goto mismatch;
	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
		goto mismatch;
	if (oldflags & ROOTCONTEXT_MNT) {
		struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
		struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
			    "different security settings for (dev %s, "
			    "type %s)\n", newsb->s_id, newsb->s_type->name);
	return -EBUSY;
}

static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
857
					struct super_block *newsb)
L
Linus Torvalds 已提交
858
{
859 860
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
861

862 863 864
	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
865

866 867
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
868
	 * mount options.  thus we can safely deal with this superblock later
869
	 */
870
	if (!ss_initialized)
871
		return 0;
872 873

	/* how can we clone if the old one wasn't set up?? */
874
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
875

876
	/* if fs is reusing a sb, make sure that the contexts match */
877
	if (newsbsec->flags & SE_SBINITIALIZED)
878
		return selinux_cmp_sb_context(oldsb, newsb);
879

880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898
	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
899
	}
900 901 902 903 904
	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
905

906
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
907 908
	}

909 910
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
911
	return 0;
912 913
}

914 915
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
916
{
917
	char *p;
918 919
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
920
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
921

922
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
923

924 925 926 927
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
928

929 930
		if (!*p)
			continue;
L
Linus Torvalds 已提交
931

932
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
933

934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985
		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;
986 987
		case Opt_labelsupport:
			break;
988 989 990 991
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
992 993 994

		}
	}
995

996 997 998 999 1000 1001 1002 1003 1004 1005 1006
	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;
	}

1007
	if (fscontext) {
1008 1009
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1010 1011
	}
	if (context) {
1012 1013
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1014 1015
	}
	if (rootcontext) {
1016 1017
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1018 1019
	}
	if (defcontext) {
1020 1021
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1022 1023
	}

1024 1025 1026
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1027 1028 1029 1030 1031
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1032 1033
	return rc;
}
1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054
/*
 * 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:
1055
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1056 1057 1058 1059 1060

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1061

A
Adrian Bunk 已提交
1062 1063
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1064 1065 1066 1067 1068
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1069 1070 1071 1072 1073 1074
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088

		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;
1089
		case SBLABEL_MNT:
1090 1091 1092
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1093 1094
		default:
			BUG();
1095
			return;
1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113
		};
		/* 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);
1114 1115 1116 1117
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1118
		return rc;
1119
	}
1120 1121 1122 1123 1124 1125 1126 1127

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150
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;
}

1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
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
1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176
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:
1177 1178 1179 1180
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1181
		case SOCK_DGRAM:
1182 1183 1184 1185
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1186 1187
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1188
		default:
L
Linus Torvalds 已提交
1189 1190 1191 1192 1193 1194 1195 1196 1197
			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;
1198
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211
			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;
1212 1213
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
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Linus Torvalds 已提交
1214 1215 1216 1217 1218 1219 1220
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1221 1222
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
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Linus Torvalds 已提交
1223 1224 1225 1226 1227 1228
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1229
static int selinux_proc_get_sid(struct dentry *dentry,
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Linus Torvalds 已提交
1230 1231 1232
				u16 tclass,
				u32 *sid)
{
1233 1234
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1235

1236
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1237 1238 1239
	if (!buffer)
		return -ENOMEM;

1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251
	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
1252 1253 1254 1255 1256
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1257
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279
				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;

1280
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1281
	if (isec->initialized)
1282
		goto out_unlock;
L
Linus Torvalds 已提交
1283 1284

	sbsec = inode->i_sb->s_security;
1285
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1286 1287 1288 1289 1290 1291 1292
		/* 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);
1293
		goto out_unlock;
L
Linus Torvalds 已提交
1294 1295 1296
	}

	switch (sbsec->behavior) {
1297 1298
	case SECURITY_FS_USE_NATIVE:
		break;
L
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1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314
	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) {
1315 1316 1317 1318 1319 1320 1321 1322 1323
			/*
			 * 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.
			 */
1324
			goto out_unlock;
L
Linus Torvalds 已提交
1325 1326 1327
		}

		len = INITCONTEXTLEN;
1328
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1329 1330 1331
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1332
			goto out_unlock;
L
Linus Torvalds 已提交
1333
		}
1334
		context[len] = '\0';
L
Linus Torvalds 已提交
1335 1336 1337
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1338 1339
			kfree(context);

L
Linus Torvalds 已提交
1340 1341 1342 1343 1344
			/* 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);
1345
				goto out_unlock;
L
Linus Torvalds 已提交
1346 1347
			}
			len = rc;
1348
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1349 1350 1351
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1352
				goto out_unlock;
L
Linus Torvalds 已提交
1353
			}
1354
			context[len] = '\0';
L
Linus Torvalds 已提交
1355 1356 1357 1358 1359 1360 1361
			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
1362
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1363
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1364 1365
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1366
				goto out_unlock;
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1367 1368 1369 1370 1371
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1372
			rc = security_context_to_sid_default(context, rc, &sid,
1373 1374
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1375
			if (rc) {
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
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Linus Torvalds 已提交
1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406
				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);
1407 1408
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
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Linus Torvalds 已提交
1409
		if (rc)
1410
			goto out_unlock;
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Linus Torvalds 已提交
1411 1412
		isec->sid = sid;
		break;
1413 1414 1415
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1416
	default:
1417
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1418 1419
		isec->sid = sbsec->sid;

1420
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447
			/* We must have a dentry to determine the label on
			 * procfs inodes */
			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);
			/*
			 * This 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.
			 */
			if (!dentry)
				goto out_unlock;
			isec->sclass = inode_mode_to_security_class(inode->i_mode);
			rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
			dput(dentry);
			if (rc)
				goto out_unlock;
			isec->sid = sid;
L
Linus Torvalds 已提交
1448 1449 1450 1451 1452 1453
		}
		break;
	}

	isec->initialized = 1;

1454 1455
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488
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
1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501
/*
 * 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);
}

1502
/*
1503
 * Check permission between a pair of tasks, e.g. signal checks,
1504 1505
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1506
 * - this uses the default subjective creds of tsk1
1507 1508 1509
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1510 1511
			 u32 perms)
{
1512 1513
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1514

1515 1516 1517 1518 1519
	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
1520 1521
}

1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
/*
 * 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);
}

1538 1539 1540 1541
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1542
/* Check whether a task is allowed to use a capability. */
1543
static int cred_has_capability(const struct cred *cred,
1544
			       int cap, int audit)
L
Linus Torvalds 已提交
1545
{
1546
	struct common_audit_data ad;
1547
	struct av_decision avd;
1548
	u16 sclass;
1549
	u32 sid = cred_sid(cred);
1550
	u32 av = CAP_TO_MASK(cap);
1551
	int rc;
L
Linus Torvalds 已提交
1552

1553
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1554 1555
	ad.u.cap = cap;

1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566
	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();
1567
		return -EINVAL;
1568
	}
1569

1570
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1571
	if (audit == SECURITY_CAP_AUDIT) {
1572
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1573 1574 1575
		if (rc2)
			return rc2;
	}
1576
	return rc;
L
Linus Torvalds 已提交
1577 1578 1579 1580 1581 1582
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1583
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1584

1585
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1586 1587 1588 1589 1590 1591
			    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). */
1592
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1593 1594
			  struct inode *inode,
			  u32 perms,
1595
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1596 1597
{
	struct inode_security_struct *isec;
1598
	u32 sid;
L
Linus Torvalds 已提交
1599

1600 1601
	validate_creds(cred);

1602
	if (unlikely(IS_PRIVATE(inode)))
1603 1604
		return 0;

1605
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1606 1607
	isec = inode->i_security;

1608
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1609 1610 1611 1612 1613
}

/* 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. */
1614
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1615 1616 1617 1618
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1619
	struct common_audit_data ad;
1620

1621
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1622
	ad.u.dentry = dentry;
1623
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635
}

/* 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;

1636
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1637
	ad.u.path = *path;
1638
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1639 1640
}

1641 1642 1643 1644 1645 1646 1647 1648 1649
/* Same as path_has_perm, but uses the inode from the file struct. */
static inline int file_path_has_perm(const struct cred *cred,
				     struct file *file,
				     u32 av)
{
	struct common_audit_data ad;

	ad.type = LSM_AUDIT_DATA_PATH;
	ad.u.path = file->f_path;
1650
	return inode_has_perm(cred, file_inode(file), av, &ad);
1651 1652
}

L
Linus Torvalds 已提交
1653 1654 1655 1656 1657 1658 1659 1660
/* 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. */
1661 1662 1663
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1664 1665
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1666
	struct inode *inode = file_inode(file);
1667
	struct common_audit_data ad;
1668
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1669 1670
	int rc;

1671
	ad.type = LSM_AUDIT_DATA_PATH;
1672
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1673

1674 1675
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1676 1677 1678 1679
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1680
			goto out;
L
Linus Torvalds 已提交
1681 1682 1683
	}

	/* av is zero if only checking access to the descriptor. */
1684
	rc = 0;
L
Linus Torvalds 已提交
1685
	if (av)
1686
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1687

1688 1689
out:
	return rc;
L
Linus Torvalds 已提交
1690 1691 1692 1693 1694 1695 1696
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1697
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1698 1699
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1700
	u32 sid, newsid;
1701
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1702 1703 1704 1705 1706
	int rc;

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

1707 1708 1709
	sid = tsec->sid;
	newsid = tsec->create_sid;

1710
	ad.type = LSM_AUDIT_DATA_DENTRY;
1711
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1712

1713
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1714 1715 1716 1717 1718
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1719
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1720 1721
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1722 1723 1724 1725
		if (rc)
			return rc;
	}

1726
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1727 1728 1729 1730 1731 1732 1733 1734
	if (rc)
		return rc;

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

1735 1736 1737 1738
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1739
	u32 sid = task_sid(ctx);
1740

1741
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1742 1743
}

1744 1745 1746
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1747 1748 1749 1750 1751 1752 1753 1754

/* 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;
1755
	struct common_audit_data ad;
1756
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1757 1758 1759 1760 1761 1762
	u32 av;
	int rc;

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

1763
	ad.type = LSM_AUDIT_DATA_DENTRY;
1764
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1765 1766 1767

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1768
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782
	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
1783 1784
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1785 1786 1787
		return 0;
	}

1788
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1789 1790 1791 1792 1793 1794 1795 1796 1797
	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;
1798
	struct common_audit_data ad;
1799
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1800 1801 1802 1803 1804 1805 1806 1807 1808
	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;

1809
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1810

1811
	ad.u.dentry = old_dentry;
1812
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1813 1814 1815
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1816
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1817 1818 1819 1820
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1821
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1822 1823 1824 1825 1826
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1827
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1828 1829 1830
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1831
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1832 1833 1834 1835 1836
	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);
1837
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1838 1839 1840 1841 1842 1843 1844 1845 1846 1847
				  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. */
1848
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1849 1850
			       struct super_block *sb,
			       u32 perms,
1851
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1852 1853
{
	struct superblock_security_struct *sbsec;
1854
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1855 1856

	sbsec = sb->s_security;
1857
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1858 1859 1860 1861 1862 1863 1864
}

/* 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
1865
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887
		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;
}

1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910
/* 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
1911
/*
1912
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1913 1914
 * open permission.
 */
1915
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1916
{
1917
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1918

1919 1920 1921
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1922 1923 1924
	return av;
}

L
Linus Torvalds 已提交
1925 1926
/* Hook functions begin here. */

1927
static int selinux_ptrace_access_check(struct task_struct *child,
1928
				     unsigned int mode)
L
Linus Torvalds 已提交
1929 1930 1931
{
	int rc;

1932
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1933 1934 1935
	if (rc)
		return rc;

1936
	if (mode & PTRACE_MODE_READ) {
1937 1938 1939
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1940 1941
	}

1942
	return current_has_perm(child, PROCESS__PTRACE);
1943 1944 1945 1946 1947 1948
}

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

1949
	rc = cap_ptrace_traceme(parent);
1950 1951 1952 1953
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1954 1955 1956
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1957
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1958 1959 1960
{
	int error;

1961
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1962 1963 1964
	if (error)
		return error;

1965
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1966 1967
}

D
David Howells 已提交
1968 1969 1970 1971
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
1972 1973 1974
{
	int error;

1975
	error = cap_capset(new, old,
D
David Howells 已提交
1976
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1977 1978 1979
	if (error)
		return error;

D
David Howells 已提交
1980
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1981 1982
}

1983 1984 1985 1986 1987 1988 1989 1990 1991 1992
/*
 * (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.
 */

1993 1994
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1995 1996 1997
{
	int rc;

1998
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1999 2000 2001
	if (rc)
		return rc;

2002
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
2003 2004 2005 2006
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2007
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2008 2009 2010 2011 2012 2013
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2014 2015 2016 2017 2018
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2019
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2020 2021 2022 2023
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2024
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2025 2026 2027 2028
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2029 2030 2031 2032 2033 2034
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2035 2036
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2037
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2038 2039
}

2040
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2041 2042 2043 2044
{
	int rc;

	switch (type) {
2045 2046
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2047 2048
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2049 2050 2051 2052
	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:
2053 2054
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2055 2056 2057 2058 2059
	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 */
2060 2061 2062
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074
	}
	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.
 */
2075
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2076 2077 2078
{
	int rc, cap_sys_admin = 0;

2079
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2080
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2081 2082 2083
	if (rc == 0)
		cap_sys_admin = 1;

2084
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2085 2086 2087 2088
}

/* binprm security operations */

2089
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2090
{
2091 2092
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2093
	struct inode_security_struct *isec;
2094
	struct common_audit_data ad;
A
Al Viro 已提交
2095
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2096 2097
	int rc;

2098
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2099 2100 2101
	if (rc)
		return rc;

2102 2103 2104
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2105 2106
		return 0;

2107 2108
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2109 2110 2111
	isec = inode->i_security;

	/* Default to the current task SID. */
2112 2113
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2114

2115
	/* Reset fs, key, and sock SIDs on execve. */
2116 2117 2118
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2119

2120 2121
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2122
		/* Reset exec SID on execve. */
2123
		new_tsec->exec_sid = 0;
2124 2125

		/*
2126 2127
		 * Minimize confusion: if no_new_privs or nosuid and a
		 * transition is explicitly requested, then fail the exec.
2128 2129 2130
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
2131 2132
		if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
			return -EACCES;
L
Linus Torvalds 已提交
2133 2134
	} else {
		/* Check for a default transition on this program. */
2135
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2136 2137
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2138 2139 2140 2141
		if (rc)
			return rc;
	}

2142
	ad.type = LSM_AUDIT_DATA_PATH;
2143
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2144

2145 2146
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2147
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2148

2149 2150
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2151 2152 2153 2154 2155
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2156
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2157 2158 2159 2160
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2161
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2162 2163 2164 2165
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183
		/* 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();
2184
			tracer = ptrace_parent(current);
2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198
			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
2199

2200 2201
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2202 2203 2204 2205 2206
	}

	return 0;
}

2207
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2208
{
2209
	const struct task_security_struct *tsec = current_security();
2210
	u32 sid, osid;
L
Linus Torvalds 已提交
2211 2212
	int atsecure = 0;

2213 2214 2215 2216
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2217 2218 2219
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2220
		atsecure = avc_has_perm(osid, sid,
2221 2222
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2223 2224
	}

2225
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2226 2227
}

A
Al Viro 已提交
2228 2229 2230 2231 2232
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
2233
/* Derived from fs/exec.c:flush_old_files. */
2234 2235
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2236 2237
{
	struct file *file, *devnull = NULL;
2238
	struct tty_struct *tty;
2239
	int drop_tty = 0;
A
Al Viro 已提交
2240
	unsigned n;
L
Linus Torvalds 已提交
2241

2242
	tty = get_current_tty();
L
Linus Torvalds 已提交
2243
	if (tty) {
N
Nick Piggin 已提交
2244
		spin_lock(&tty_files_lock);
2245
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2246
			struct tty_file_private *file_priv;
2247

L
Linus Torvalds 已提交
2248
			/* Revalidate access to controlling tty.
2249 2250 2251 2252
			   Use file_path_has_perm on the tty path directly
			   rather than using file_has_perm, as this particular
			   open file may belong to another process and we are
			   only interested in the inode-based check here. */
N
Nick Piggin 已提交
2253 2254 2255
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2256
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2257
				drop_tty = 1;
L
Linus Torvalds 已提交
2258
		}
N
Nick Piggin 已提交
2259
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2260
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2261
	}
2262 2263 2264
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2265 2266

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2267 2268 2269
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2270

A
Al Viro 已提交
2271
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2272 2273 2274 2275 2276 2277 2278
	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
2279
		fput(devnull);
L
Linus Torvalds 已提交
2280 2281
}

2282 2283 2284 2285
/*
 * 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
2286
{
2287 2288 2289
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2290

2291 2292 2293
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2294

2295 2296
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2297

2298 2299
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2300

2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313
	/* 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) {
2314 2315
		/* protect against do_prlimit() */
		task_lock(current);
2316 2317 2318 2319
		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
2320
		}
2321 2322
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2323 2324 2325 2326
	}
}

/*
2327 2328
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2329
 */
2330
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2331
{
2332
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2333
	struct itimerval itimer;
2334
	u32 osid, sid;
L
Linus Torvalds 已提交
2335 2336
	int rc, i;

2337 2338 2339 2340
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2341 2342
		return;

2343 2344 2345 2346 2347 2348 2349 2350
	/* 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
2351 2352 2353 2354 2355
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2356 2357 2358 2359 2360
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2361 2362 2363
		spin_unlock_irq(&current->sighand->siglock);
	}

2364 2365
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2366
	read_lock(&tasklist_lock);
2367
	__wake_up_parent(current, current->real_parent);
2368
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392
}

/* 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)
{
2393 2394 2395
	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) ||
2396 2397
		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
2398 2399 2400 2401 2402 2403 2404
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2405
	} else
L
Linus Torvalds 已提交
2406 2407 2408 2409 2410
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2411 2412
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2413 2414 2415 2416 2417 2418
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2419
	} else
2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431
		*first = 0;

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

2432
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2433 2434 2435 2436
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2437
	int open_quote = 0;
L
Linus Torvalds 已提交
2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452

	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 {
2453 2454 2455 2456
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2457 2458 2459
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2460
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2461 2462 2463 2464 2465 2466 2467
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2468
	strcpy(in_save, nosec_save);
2469
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2470 2471 2472 2473
out:
	return rc;
}

2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508
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;

2509
		if (flags[i] == SBLABEL_MNT)
2510 2511
			continue;
		len = strlen(mount_options[i]);
2512 2513
		rc = security_context_to_sid(mount_options[i], len, &sid,
					     GFP_KERNEL);
2514 2515
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2516 2517
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554
			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 "
2555 2556
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2557 2558 2559
	goto out_free_opts;
}

2560
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2561
{
2562
	const struct cred *cred = current_cred();
2563
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2564 2565 2566 2567 2568 2569
	int rc;

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

2570 2571 2572 2573
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2574
	ad.type = LSM_AUDIT_DATA_DENTRY;
2575
	ad.u.dentry = sb->s_root;
2576
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2577 2578
}

2579
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2580
{
2581
	const struct cred *cred = current_cred();
2582
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2583

2584
	ad.type = LSM_AUDIT_DATA_DENTRY;
2585
	ad.u.dentry = dentry->d_sb->s_root;
2586
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2587 2588
}

A
Al Viro 已提交
2589
static int selinux_mount(const char *dev_name,
2590
			 struct path *path,
A
Al Viro 已提交
2591
			 const char *type,
2592 2593
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2594
{
2595
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2596 2597

	if (flags & MS_REMOUNT)
2598
		return superblock_has_perm(cred, path->dentry->d_sb,
2599
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2600
	else
E
Eric Paris 已提交
2601
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2602 2603 2604 2605
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2606
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2607

2608
	return superblock_has_perm(cred, mnt->mnt_sb,
2609
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623
}

/* 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);
}

2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
					struct qstr *name, void **ctx,
					u32 *ctxlen)
{
	const struct cred *cred = current_cred();
	struct task_security_struct *tsec;
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
	struct inode *dir = dentry->d_parent->d_inode;
	u32 newsid;
	int rc;

	tsec = cred->security;
	dsec = dir->i_security;
	sbsec = dir->i_sb->s_security;

	if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
		newsid = tsec->create_sid;
	} else {
		rc = security_transition_sid(tsec->sid, dsec->sid,
					     inode_mode_to_security_class(mode),
					     name,
					     &newsid);
		if (rc) {
			printk(KERN_WARNING
				"%s: security_transition_sid failed, rc=%d\n",
			       __func__, -rc);
			return rc;
		}
	}

	return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}

2658
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2659 2660
				       const struct qstr *qstr,
				       const char **name,
2661
				       void **value, size_t *len)
2662
{
2663
	const struct task_security_struct *tsec = current_security();
2664 2665
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2666
	u32 sid, newsid, clen;
2667
	int rc;
2668
	char *context;
2669 2670 2671 2672

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

2673 2674 2675
	sid = tsec->sid;
	newsid = tsec->create_sid;

2676 2677 2678
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2679
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2680
		rc = security_transition_sid(sid, dsec->sid,
2681
					     inode_mode_to_security_class(inode->i_mode),
2682
					     qstr, &newsid);
2683 2684 2685 2686
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2687
			       __func__,
2688 2689 2690 2691 2692
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2693
	/* Possibly defer initialization to selinux_complete_init. */
2694
	if (sbsec->flags & SE_SBINITIALIZED) {
2695 2696 2697 2698 2699
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2700

2701
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2702 2703
		return -EOPNOTSUPP;

2704 2705
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2706

2707
	if (value && len) {
2708
		rc = security_sid_to_context_force(newsid, &context, &clen);
2709
		if (rc)
2710 2711 2712
			return rc;
		*value = context;
		*len = clen;
2713 2714 2715 2716 2717
	}

	return 0;
}

A
Al Viro 已提交
2718
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737
{
	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);
}

2738
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2739 2740 2741 2742 2743 2744 2745 2746 2747
{
	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
2748
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2749 2750 2751 2752 2753
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2754
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2755 2756 2757 2758 2759 2760
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2761 2762
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2763
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2764 2765 2766 2767
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2768
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2769

E
Eric Paris 已提交
2770
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2771 2772
}

2773 2774
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
2775
					   int result,
2776
					   unsigned flags)
L
Linus Torvalds 已提交
2777
{
2778
	struct common_audit_data ad;
2779 2780 2781
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2782
	ad.type = LSM_AUDIT_DATA_INODE;
2783 2784 2785
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2786
			    audited, denied, result, &ad, flags);
2787 2788 2789 2790 2791
	if (rc)
		return rc;
	return 0;
}

2792
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2793
{
2794
	const struct cred *cred = current_cred();
2795 2796
	u32 perms;
	bool from_access;
2797
	unsigned flags = mask & MAY_NOT_BLOCK;
2798 2799 2800 2801 2802
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2803

2804
	from_access = mask & MAY_ACCESS;
2805 2806
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2807 2808
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2809 2810
		return 0;

2811
	validate_creds(cred);
2812

2813 2814
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2815 2816 2817

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

2818 2819 2820 2821 2822 2823 2824 2825 2826 2827
	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;

2828
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2829 2830 2831
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2832 2833 2834 2835
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2836
	const struct cred *cred = current_cred();
2837
	unsigned int ia_valid = iattr->ia_valid;
2838
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2839

2840 2841 2842 2843 2844 2845 2846
	/* 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
2847

2848 2849
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2850
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2851

2852
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2853 2854 2855
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2856 2857 2858 2859
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2860
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2861 2862 2863 2864
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2865

E
Eric Paris 已提交
2866
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2867 2868
}

2869
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2870
{
2871 2872
	const struct cred *cred = current_cred();

2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886
	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
2887
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2888 2889
}

2890 2891
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
2892 2893 2894 2895
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2896
	struct common_audit_data ad;
2897
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2898 2899
	int rc = 0;

2900 2901
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2902 2903

	sbsec = inode->i_sb->s_security;
2904
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2905 2906
		return -EOPNOTSUPP;

2907
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2908 2909
		return -EPERM;

2910
	ad.type = LSM_AUDIT_DATA_DENTRY;
2911
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2912

2913
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2914 2915 2916 2917
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

2918
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2919
	if (rc == -EINVAL) {
2920 2921 2922 2923 2924 2925 2926
		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 */
2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2937 2938 2939 2940 2941
			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);

2942
			return rc;
2943
		}
2944 2945
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2946 2947 2948
	if (rc)
		return rc;

2949
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2950 2951 2952 2953
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2954
	rc = security_validate_transition(isec->sid, newsid, sid,
2955
					  isec->sclass);
L
Linus Torvalds 已提交
2956 2957 2958 2959 2960 2961 2962 2963 2964 2965
	if (rc)
		return rc;

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

2966
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2967
					const void *value, size_t size,
2968
					int flags)
L
Linus Torvalds 已提交
2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979
{
	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;
	}

2980
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2981
	if (rc) {
2982 2983 2984
		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
2985 2986 2987
		return;
	}

2988
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
2989
	isec->sid = newsid;
2990 2991
	isec->initialized = 1;

L
Linus Torvalds 已提交
2992 2993 2994
	return;
}

2995
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2996
{
2997 2998
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2999
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3000 3001
}

3002
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3003
{
3004 3005
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3006
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3007 3008
}

3009
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3010
{
3011 3012
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3013 3014 3015 3016 3017 3018

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

3019
/*
3020
 * Copy the inode security context value to the user.
3021 3022 3023
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3024
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3025
{
3026 3027 3028
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
3029
	struct inode_security_struct *isec = inode->i_security;
3030

3031 3032
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3033

3034 3035 3036 3037 3038 3039 3040 3041 3042
	/*
	 * 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.
	 */
3043
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3044
				SECURITY_CAP_NOAUDIT);
3045 3046 3047 3048 3049
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3050 3051 3052 3053 3054 3055 3056 3057 3058 3059
	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
3060 3061 3062
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3063
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3064 3065 3066 3067 3068 3069 3070 3071 3072 3073 3074
{
	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;

3075
	rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3076 3077 3078
	if (rc)
		return rc;

3079
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3080
	isec->sid = newsid;
3081
	isec->initialized = 1;
L
Linus Torvalds 已提交
3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092
	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;
}

3093 3094 3095 3096 3097 3098
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
3099 3100
/* file security operations */

3101
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3102
{
3103
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3104
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3105 3106 3107 3108 3109

	/* 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;

3110 3111
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3112 3113
}

3114 3115
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3116
	struct inode *inode = file_inode(file);
3117 3118 3119 3120
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3121
	if (!mask)
3122 3123 3124
		/* No permission to check.  Existence test. */
		return 0;

3125 3126
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3127
		/* No change since file_open check. */
3128 3129
		return 0;

3130 3131 3132
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145
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)
{
3146
	const struct cred *cred = current_cred();
3147
	int error = 0;
L
Linus Torvalds 已提交
3148

3149 3150 3151 3152 3153 3154 3155
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3156
	case FS_IOC_GETFLAGS:
3157
	/* fall through */
3158
	case FS_IOC_GETVERSION:
3159 3160
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3161

3162
	case FS_IOC_SETFLAGS:
3163
	/* fall through */
3164
	case FS_IOC_SETVERSION:
3165 3166 3167 3168 3169 3170 3171 3172 3173
		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
3174

3175 3176
	case KDSKBENT:
	case KDSKBSENT:
3177 3178
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3179 3180 3181 3182 3183 3184 3185 3186 3187
		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
3188 3189
}

3190 3191
static int default_noexec;

L
Linus Torvalds 已提交
3192 3193
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3194
	const struct cred *cred = current_cred();
D
David Howells 已提交
3195
	int rc = 0;
3196

3197 3198
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3199 3200 3201 3202 3203
		/*
		 * 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
3204
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3205
		if (rc)
D
David Howells 已提交
3206
			goto error;
L
Linus Torvalds 已提交
3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219
	}

	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;

3220
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3221
	}
D
David Howells 已提交
3222 3223 3224

error:
	return rc;
L
Linus Torvalds 已提交
3225 3226
}

3227
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3228
{
3229 3230 3231 3232 3233 3234
	int rc;

	/* do DAC check on address space usage */
	rc = cap_mmap_addr(addr);
	if (rc)
		return rc;
L
Linus Torvalds 已提交
3235

3236
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3237
		u32 sid = current_sid();
3238 3239
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3240 3241
	}

3242
	return rc;
3243
}
L
Linus Torvalds 已提交
3244

3245 3246 3247
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258
	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)
{
3259
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3260 3261 3262 3263

	if (selinux_checkreqprot)
		prot = reqprot;

3264 3265
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3266
		int rc = 0;
3267 3268
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3269
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3270 3271 3272
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3273
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3274 3275 3276 3277 3278 3279 3280 3281
		} 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
3282
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3283
		}
3284 3285 3286
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3287 3288 3289 3290 3291 3292

	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)
{
3293 3294 3295
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3296 3297 3298 3299 3300
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3301
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3302 3303 3304
	int err = 0;

	switch (cmd) {
3305 3306
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3307
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3308
			break;
3309 3310 3311 3312 3313 3314 3315
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3316
	case F_GETOWNER_UIDS:
3317
		/* Just check FD__USE permission */
3318
		err = file_has_perm(cred, file, 0);
3319 3320 3321 3322
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3323 3324 3325
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3326
#if BITS_PER_LONG == 32
3327 3328 3329
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3330
#endif
3331
		err = file_has_perm(cred, file, FILE__LOCK);
3332
		break;
L
Linus Torvalds 已提交
3333 3334 3335 3336 3337 3338 3339 3340 3341 3342
	}

	return err;
}

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

	fsec = file->f_security;
3343
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3344 3345 3346 3347 3348 3349 3350

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3351
	struct file *file;
3352
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3353 3354 3355 3356
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3357
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3358 3359 3360 3361 3362 3363 3364 3365

	fsec = file->f_security;

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

3366
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3367 3368 3369 3370 3371
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3372 3373 3374
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3375 3376
}

3377
static int selinux_file_open(struct file *file, const struct cred *cred)
3378 3379 3380
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3381

3382
	fsec = file->f_security;
A
Al Viro 已提交
3383
	isec = file_inode(file)->i_security;
3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400
	/*
	 * 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.
	 */
3401
	return file_path_has_perm(cred, file, open_file_to_av(file));
3402 3403
}

L
Linus Torvalds 已提交
3404 3405 3406 3407
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3408
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3409 3410
}

3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425
/*
 * 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
3426 3427 3428 3429
/*
 * 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
3430
{
D
David Howells 已提交
3431
	struct task_security_struct *tsec = cred->security;
3432

3433 3434 3435 3436 3437
	/*
	 * 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);
3438
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3439 3440
	kfree(tsec);
}
L
Linus Torvalds 已提交
3441

D
David Howells 已提交
3442 3443 3444 3445 3446 3447 3448 3449
/*
 * 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
3450

D
David Howells 已提交
3451
	old_tsec = old->security;
L
Linus Torvalds 已提交
3452

D
David Howells 已提交
3453 3454 3455
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3456

D
David Howells 已提交
3457
	new->security = tsec;
L
Linus Torvalds 已提交
3458 3459 3460
	return 0;
}

3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471
/*
 * 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;
}

3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512
/*
 * 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;
3513
	return ret;
3514 3515
}

3516
static int selinux_kernel_module_request(char *kmod_name)
3517
{
3518 3519 3520 3521 3522
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3523
	ad.type = LSM_AUDIT_DATA_KMOD;
3524 3525 3526 3527
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3528 3529
}

L
Linus Torvalds 已提交
3530 3531
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3532
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3533 3534 3535 3536
}

static int selinux_task_getpgid(struct task_struct *p)
{
3537
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3538 3539 3540 3541
}

static int selinux_task_getsid(struct task_struct *p)
{
3542
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3543 3544
}

3545 3546
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3547
	*secid = task_sid(p);
3548 3549
}

L
Linus Torvalds 已提交
3550 3551 3552 3553
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3554
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3555 3556 3557
	if (rc)
		return rc;

3558
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3559 3560
}

3561 3562
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3563 3564
	int rc;

3565
	rc = cap_task_setioprio(p, ioprio);
3566 3567 3568
	if (rc)
		return rc;

3569
	return current_has_perm(p, PROCESS__SETSCHED);
3570 3571
}

3572 3573
static int selinux_task_getioprio(struct task_struct *p)
{
3574
	return current_has_perm(p, PROCESS__GETSCHED);
3575 3576
}

3577 3578
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3579
{
3580
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3581 3582 3583 3584

	/* 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
3585
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3586
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3587
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3588 3589 3590 3591

	return 0;
}

3592
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3593
{
3594 3595
	int rc;

3596
	rc = cap_task_setscheduler(p);
3597 3598 3599
	if (rc)
		return rc;

3600
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3601 3602 3603 3604
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3605
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3606 3607
}

3608 3609
static int selinux_task_movememory(struct task_struct *p)
{
3610
	return current_has_perm(p, PROCESS__SETSCHED);
3611 3612
}

3613 3614
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3615 3616 3617 3618 3619 3620 3621 3622
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3623
	if (secid)
3624 3625
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3626
	else
3627
		rc = current_has_perm(p, perm);
3628
	return rc;
L
Linus Torvalds 已提交
3629 3630 3631 3632
}

static int selinux_task_wait(struct task_struct *p)
{
3633
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3634 3635 3636 3637 3638 3639
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3640
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3641

3642
	isec->sid = sid;
L
Linus Torvalds 已提交
3643 3644 3645 3646
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3647
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3648
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3649 3650 3651 3652
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3653
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3654 3655 3656 3657 3658 3659 3660 3661
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3662 3663
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3664 3665
	ret = 0;

3666 3667 3668
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3669
	switch (ih->protocol) {
3670 3671
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3672

3673 3674
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3675 3676 3677 3678 3679 3680

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

3681 3682
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3683
		break;
3684 3685 3686 3687 3688 3689 3690 3691
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3692
		offset += ihlen;
3693
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3694
		if (uh == NULL)
3695
			break;
L
Linus Torvalds 已提交
3696

3697 3698
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3699 3700
		break;
	}
L
Linus Torvalds 已提交
3701

J
James Morris 已提交
3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712
	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;

3713 3714
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3715
		break;
3716
	}
J
James Morris 已提交
3717

3718 3719 3720
	default:
		break;
	}
L
Linus Torvalds 已提交
3721 3722 3723 3724 3725 3726 3727
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3728
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3729
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3730 3731 3732 3733
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3734
	__be16 frag_off;
L
Linus Torvalds 已提交
3735

3736
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3737 3738 3739 3740
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3741 3742
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3743 3744 3745 3746
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3747
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3748 3749 3750
	if (offset < 0)
		goto out;

3751 3752 3753
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3754 3755
	switch (nexthdr) {
	case IPPROTO_TCP: {
3756
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3757 3758 3759 3760 3761

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

3762 3763
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3764 3765 3766 3767 3768 3769 3770 3771 3772 3773
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3774 3775
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3776 3777 3778
		break;
	}

J
James Morris 已提交
3779 3780 3781 3782 3783 3784 3785
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3786 3787
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3788
		break;
3789
	}
J
James Morris 已提交
3790

L
Linus Torvalds 已提交
3791 3792 3793 3794 3795 3796 3797 3798 3799 3800
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3801
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3802
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3803
{
3804 3805
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3806

3807
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3808
	case PF_INET:
3809
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3810 3811
		if (ret)
			goto parse_error;
3812 3813
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3814
		goto okay;
L
Linus Torvalds 已提交
3815 3816 3817

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3818
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3819 3820
		if (ret)
			goto parse_error;
3821 3822
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3823
		goto okay;
L
Linus Torvalds 已提交
3824 3825
#endif	/* IPV6 */
	default:
3826 3827
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3828 3829
	}

3830 3831 3832 3833
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3834
	return ret;
3835 3836 3837 3838 3839

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3840 3841
}

3842
/**
3843
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3844
 * @skb: the packet
3845
 * @family: protocol family
3846
 * @sid: the packet's peer label SID
3847 3848
 *
 * Description:
3849 3850 3851 3852 3853 3854
 * 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.
3855 3856
 *
 */
3857
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3858
{
3859
	int err;
3860 3861
	u32 xfrm_sid;
	u32 nlbl_sid;
3862
	u32 nlbl_type;
3863

3864
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3865 3866 3867 3868 3869
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3870

3871 3872 3873 3874 3875
	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");
3876
		return -EACCES;
3877
	}
3878 3879

	return 0;
3880 3881
}

3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905
/**
 * selinux_conn_sid - Determine the child socket label for a connection
 * @sk_sid: the parent socket's SID
 * @skb_sid: the packet's SID
 * @conn_sid: the resulting connection SID
 *
 * If @skb_sid is valid then the user:role:type information from @sk_sid is
 * combined with the MLS information from @skb_sid in order to create
 * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
 * of @sk_sid.  Returns zero on success, negative values on failure.
 *
 */
static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
{
	int err = 0;

	if (skb_sid != SECSID_NULL)
		err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
	else
		*conn_sid = sk_sid;

	return err;
}

L
Linus Torvalds 已提交
3906
/* socket security operations */
3907

3908 3909
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3910
{
3911 3912 3913 3914 3915 3916 3917
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3918 3919
}

3920
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3921
{
3922
	struct sk_security_struct *sksec = sk->sk_security;
3923
	struct common_audit_data ad;
3924
	struct lsm_network_audit net = {0,};
3925
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3926

3927 3928
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3929

3930
	ad.type = LSM_AUDIT_DATA_NET;
3931 3932
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3933

3934
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3935 3936 3937 3938 3939
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3940
	const struct task_security_struct *tsec = current_security();
3941
	u32 newsid;
3942
	u16 secclass;
3943
	int rc;
L
Linus Torvalds 已提交
3944 3945

	if (kern)
3946
		return 0;
3947 3948

	secclass = socket_type_to_security_class(family, type, protocol);
3949 3950 3951 3952
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3953
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3954 3955
}

V
Venkat Yekkirala 已提交
3956 3957
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3958
{
3959
	const struct task_security_struct *tsec = current_security();
3960
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3961
	struct sk_security_struct *sksec;
3962 3963
	int err = 0;

3964 3965
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3966 3967
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3968 3969 3970 3971 3972
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3973

L
Linus Torvalds 已提交
3974 3975
	isec->initialized = 1;

3976 3977 3978
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3979
		sksec->sclass = isec->sclass;
3980
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3981 3982
	}

V
Venkat Yekkirala 已提交
3983
	return err;
L
Linus Torvalds 已提交
3984 3985 3986 3987 3988 3989 3990 3991
}

/* 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)
{
3992
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3993 3994 3995
	u16 family;
	int err;

3996
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3997 3998 3999 4000 4001
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4002 4003
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4004
	 */
4005
	family = sk->sk_family;
L
Linus Torvalds 已提交
4006 4007
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4008
		struct sk_security_struct *sksec = sk->sk_security;
4009
		struct common_audit_data ad;
4010
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4011 4012 4013
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4014
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025

		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;
		}

4026 4027 4028
		if (snum) {
			int low, high;

4029
			inet_get_local_port_range(sock_net(sk), &low, &high);
4030 4031

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
4032 4033
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4034 4035
				if (err)
					goto out;
4036
				ad.type = LSM_AUDIT_DATA_NET;
4037 4038 4039
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4040 4041
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4042 4043 4044 4045
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4046
		}
4047

4048
		switch (sksec->sclass) {
4049
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4050 4051
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4052

4053
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4054 4055
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4056 4057 4058 4059 4060

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4061 4062 4063 4064
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4065

4066
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4067 4068
		if (err)
			goto out;
4069

4070
		ad.type = LSM_AUDIT_DATA_NET;
4071 4072 4073
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4074 4075

		if (family == PF_INET)
4076
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4077
		else
4078
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4079

4080 4081
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4082 4083 4084 4085 4086 4087 4088 4089 4090
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4091
	struct sock *sk = sock->sk;
4092
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4093 4094
	int err;

4095
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4096 4097 4098 4099
	if (err)
		return err;

	/*
J
James Morris 已提交
4100
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4101
	 */
4102 4103
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4104
		struct common_audit_data ad;
4105
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4106 4107 4108
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4109
		u32 sid, perm;
L
Linus Torvalds 已提交
4110 4111 4112

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4113
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4114 4115 4116 4117
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4118
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4119 4120 4121 4122
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4123
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4124 4125 4126
		if (err)
			goto out;

4127
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4128 4129
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4130
		ad.type = LSM_AUDIT_DATA_NET;
4131 4132 4133
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4134
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4135 4136 4137 4138
		if (err)
			goto out;
	}

4139 4140
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4141 4142 4143 4144 4145 4146
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4147
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4148 4149 4150 4151 4152 4153 4154 4155
}

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

4156
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170
	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,
4171
				  int size)
L
Linus Torvalds 已提交
4172
{
4173
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4174 4175 4176 4177 4178
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4179
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4180 4181 4182 4183
}

static int selinux_socket_getsockname(struct socket *sock)
{
4184
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4185 4186 4187 4188
}

static int selinux_socket_getpeername(struct socket *sock)
{
4189
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4190 4191
}

4192
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4193
{
4194 4195
	int err;

4196
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4197 4198 4199 4200
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4201 4202 4203 4204 4205
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4206
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4207 4208 4209 4210
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4211
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4212 4213
}

4214 4215
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4216 4217
					      struct sock *newsk)
{
4218 4219
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4220
	struct sk_security_struct *sksec_new = newsk->sk_security;
4221
	struct common_audit_data ad;
4222
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4223 4224
	int err;

4225
	ad.type = LSM_AUDIT_DATA_NET;
4226 4227
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4228

4229 4230
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4231 4232 4233 4234 4235
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4236 4237 4238 4239 4240
	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;
4241

4242 4243 4244 4245
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4246 4247 4248 4249 4250
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4251 4252
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4253
	struct common_audit_data ad;
4254
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4255

4256
	ad.type = LSM_AUDIT_DATA_NET;
4257 4258
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4259

4260 4261
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4262 4263
}

4264 4265
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4266
				    struct common_audit_data *ad)
4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286
{
	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);
}

4287
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4288
				       u16 family)
4289
{
4290
	int err = 0;
4291 4292
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4293
	struct common_audit_data ad;
4294
	struct lsm_network_audit net = {0,};
4295 4296
	char *addrp;

4297
	ad.type = LSM_AUDIT_DATA_NET;
4298 4299 4300
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4301 4302 4303
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4304

4305
	if (selinux_secmark_enabled()) {
4306
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4307
				   PACKET__RECV, &ad);
4308 4309 4310
		if (err)
			return err;
	}
4311

4312 4313 4314 4315
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4316

4317 4318 4319 4320 4321
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4322
	int err;
4323
	struct sk_security_struct *sksec = sk->sk_security;
4324 4325
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4326
	struct common_audit_data ad;
4327
	struct lsm_network_audit net = {0,};
4328
	char *addrp;
4329 4330
	u8 secmark_active;
	u8 peerlbl_active;
4331 4332

	if (family != PF_INET && family != PF_INET6)
4333
		return 0;
4334 4335

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4336
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4337 4338
		family = PF_INET;

4339 4340 4341 4342
	/* 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. */
4343
	if (!selinux_policycap_netpeer)
4344 4345 4346
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4347
	peerlbl_active = selinux_peerlbl_enabled();
4348 4349 4350
	if (!secmark_active && !peerlbl_active)
		return 0;

4351
	ad.type = LSM_AUDIT_DATA_NET;
4352 4353 4354
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4355
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4356
	if (err)
4357
		return err;
4358

4359
	if (peerlbl_active) {
4360 4361 4362
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4363 4364
		if (err)
			return err;
4365
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4366
					       peer_sid, &ad);
4367 4368
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4369
			return err;
4370
		}
4371 4372
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4373
		if (err) {
4374
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4375 4376
			return err;
		}
4377 4378
	}

4379
	if (secmark_active) {
4380 4381 4382 4383 4384 4385
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4386
	return err;
L
Linus Torvalds 已提交
4387 4388
}

C
Catherine Zhang 已提交
4389 4390
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4391 4392 4393 4394
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4395
	struct sk_security_struct *sksec = sock->sk->sk_security;
4396
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4397

4398 4399
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4400
		peer_sid = sksec->peer_sid;
4401 4402
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4403

C
Catherine Zhang 已提交
4404
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4405
	if (err)
4406
		return err;
L
Linus Torvalds 已提交
4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422

	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;
}

4423
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4424
{
4425
	u32 peer_secid = SECSID_NULL;
4426
	u16 family;
C
Catherine Zhang 已提交
4427

4428 4429 4430 4431 4432
	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)
4433 4434 4435 4436 4437
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4438
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4439
	else if (skb)
4440
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4441

4442
out:
4443
	*secid = peer_secid;
4444 4445 4446
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4447 4448
}

A
Al Viro 已提交
4449
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4450
{
4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462
	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
4463 4464 4465 4466
}

static void selinux_sk_free_security(struct sock *sk)
{
4467 4468 4469 4470 4471
	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
4472 4473
}

4474
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4475
{
4476 4477
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4478

4479 4480 4481
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4482

4483
	selinux_netlbl_sk_security_reset(newsksec);
4484 4485
}

V
Venkat Yekkirala 已提交
4486
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4487
{
4488
	if (!sk)
V
Venkat Yekkirala 已提交
4489
		*secid = SECINITSID_ANY_SOCKET;
4490 4491
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4492

V
Venkat Yekkirala 已提交
4493
		*secid = sksec->sid;
4494
	}
4495 4496
}

4497
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4498 4499 4500 4501
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4502 4503 4504
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4505
	sksec->sclass = isec->sclass;
4506 4507
}

4508 4509
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4510 4511 4512
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4513
	u16 family = req->rsk_ops->family;
4514
	u32 connsid;
4515 4516
	u32 peersid;

4517
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4518 4519
	if (err)
		return err;
4520 4521 4522 4523 4524
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4525

4526
	return selinux_netlbl_inet_conn_request(req, family);
4527 4528
}

4529 4530
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4531 4532 4533 4534
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4535
	newsksec->peer_sid = req->peer_secid;
4536 4537 4538 4539
	/* 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. */
4540

P
Paul Moore 已提交
4541 4542
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4543
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4544 4545
}

4546
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4547
{
4548
	u16 family = sk->sk_family;
4549 4550
	struct sk_security_struct *sksec = sk->sk_security;

4551 4552 4553 4554 4555
	/* 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);
4556 4557
}

4558 4559 4560 4561 4562
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583
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);
}

4584 4585
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4586
{
4587
	fl->flowi_secid = req->secid;
4588 4589
}

4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607
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);
}

4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622
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);
}

4623
static int selinux_tun_dev_attach_queue(void *security)
4624
{
4625 4626 4627 4628 4629 4630 4631 4632 4633
	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;
4634 4635 4636 4637 4638 4639 4640 4641 4642
	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 */

4643
	sksec->sid = tunsec->sid;
4644
	sksec->sclass = SECCLASS_TUN_SOCKET;
4645 4646

	return 0;
4647 4648
}

4649
static int selinux_tun_dev_open(void *security)
4650
{
4651
	struct tun_security_struct *tunsec = security;
4652 4653 4654
	u32 sid = current_sid();
	int err;

4655
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4656 4657 4658 4659 4660 4661 4662
			   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;
4663
	tunsec->sid = sid;
4664 4665 4666 4667

	return 0;
}

L
Linus Torvalds 已提交
4668 4669 4670 4671 4672
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4673
	struct sk_security_struct *sksec = sk->sk_security;
4674

4675
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4676 4677 4678
		err = -EINVAL;
		goto out;
	}
4679
	nlh = nlmsg_hdr(skb);
4680

4681
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4682 4683
	if (err) {
		if (err == -EINVAL) {
4684
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4685 4686
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4687
				  nlh->nlmsg_type, sksec->sclass);
4688
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4689 4690 4691 4692 4693 4694 4695 4696 4697
				err = 0;
		}

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

4698
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4699 4700 4701 4702 4703 4704
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4705 4706
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4707
{
4708
	int err;
4709 4710
	char *addrp;
	u32 peer_sid;
4711
	struct common_audit_data ad;
4712
	struct lsm_network_audit net = {0,};
4713
	u8 secmark_active;
4714
	u8 netlbl_active;
4715
	u8 peerlbl_active;
4716

4717 4718
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4719

4720
	secmark_active = selinux_secmark_enabled();
4721
	netlbl_active = netlbl_enabled();
4722
	peerlbl_active = selinux_peerlbl_enabled();
4723 4724
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4725

4726 4727 4728
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4729
	ad.type = LSM_AUDIT_DATA_NET;
4730 4731 4732
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4733 4734 4735
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4736 4737 4738 4739 4740
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4741
			return NF_DROP;
4742 4743
		}
	}
4744 4745 4746 4747 4748 4749

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

4750 4751 4752 4753 4754 4755 4756 4757
	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;

4758 4759 4760
	return NF_ACCEPT;
}

4761
static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4762 4763 4764 4765 4766 4767 4768 4769 4770
					 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)
4771
static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4772 4773 4774 4775 4776 4777 4778 4779 4780
					 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 */

4781 4782 4783
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4784
	struct sock *sk;
4785 4786 4787 4788 4789 4790 4791 4792
	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 */
4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

		if (sk->sk_state == TCP_LISTEN)
			/* if the socket is the listening state then this
			 * packet is a SYN-ACK packet which means it needs to
			 * be labeled based on the connection/request_sock and
			 * not the parent socket.  unfortunately, we can't
			 * lookup the request_sock yet as it isn't queued on
			 * the parent socket until after the SYN-ACK is sent.
			 * the "solution" is to simply pass the packet as-is
			 * as any IP option based labeling should be copied
			 * from the initial connection request (in the IP
			 * layer).  it is far from ideal, but until we get a
			 * security label in the packet itself this is the
			 * best we can do. */
			return NF_ACCEPT;

		/* standard practice, label using the parent socket */
		sksec = sk->sk_security;
4814 4815 4816 4817 4818 4819 4820 4821 4822
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4823
static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4824 4825 4826 4827 4828 4829 4830 4831
					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);
}

4832 4833
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4834
						u16 family)
4835 4836 4837
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4838
	struct common_audit_data ad;
4839
	struct lsm_network_audit net = {0,};
4840 4841
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4842

4843 4844 4845 4846
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4847
	ad.type = LSM_AUDIT_DATA_NET;
4848 4849 4850
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4851 4852 4853
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4854
	if (selinux_secmark_enabled())
4855
		if (avc_has_perm(sksec->sid, skb->secmark,
4856
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4857
			return NF_DROP_ERR(-ECONNREFUSED);
4858

4859 4860
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4861 4862

	return NF_ACCEPT;
4863 4864
}

4865 4866
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4867
{
4868 4869
	u32 secmark_perm;
	u32 peer_sid;
4870
	struct sock *sk;
4871
	struct common_audit_data ad;
4872
	struct lsm_network_audit net = {0,};
4873 4874 4875
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4876

4877 4878 4879 4880
	/* 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. */
4881
	if (!selinux_policycap_netpeer)
4882
		return selinux_ip_postroute_compat(skb, ifindex, family);
4883 4884 4885 4886 4887 4888 4889 4890

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = selinux_peerlbl_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

	sk = skb->sk;

4891
#ifdef CONFIG_XFRM
4892 4893 4894 4895 4896
	/* 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
4897 4898 4899 4900 4901 4902 4903 4904
	 *       is NULL, in this case go ahead and apply access control.
	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
	 *       TCP listening state we cannot wait until the XFRM processing
	 *       is done as we will miss out on the SA label if we do;
	 *       unfortunately, this means more work, but it is only once per
	 *       connection. */
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
	    !(sk != NULL && sk->sk_state == TCP_LISTEN))
4905
		return NF_ACCEPT;
4906
#endif
4907

4908
	if (sk == NULL) {
4909 4910 4911 4912
		/* Without an associated socket the packet is either coming
		 * from the kernel or it is being forwarded; check the packet
		 * to determine which and if the packet is being forwarded
		 * query the packet directly to determine the security label. */
4913 4914
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4915
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4916
				return NF_DROP;
4917 4918
		} else {
			secmark_perm = PACKET__SEND;
4919
			peer_sid = SECINITSID_KERNEL;
4920
		}
4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934
	} else if (sk->sk_state == TCP_LISTEN) {
		/* Locally generated packet but the associated socket is in the
		 * listening state which means this is a SYN-ACK packet.  In
		 * this particular case the correct security label is assigned
		 * to the connection/request_sock but unfortunately we can't
		 * query the request_sock as it isn't queued on the parent
		 * socket until after the SYN-ACK packet is sent; the only
		 * viable choice is to regenerate the label like we do in
		 * selinux_inet_conn_request().  See also selinux_ip_output()
		 * for similar problems. */
		u32 skb_sid;
		struct sk_security_struct *sksec = sk->sk_security;
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953
		/* At this point, if the returned skb peerlbl is SECSID_NULL
		 * and the packet has been through at least one XFRM
		 * transformation then we must be dealing with the "final"
		 * form of labeled IPsec packet; since we've already applied
		 * all of our access controls on this packet we can safely
		 * pass the packet. */
		if (skb_sid == SECSID_NULL) {
			switch (family) {
			case PF_INET:
				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
				break;
			case PF_INET6:
				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
4954 4955 4956
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4957
	} else {
4958 4959
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4960 4961 4962 4963
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4964

4965
	ad.type = LSM_AUDIT_DATA_NET;
4966 4967 4968
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4969
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4970
		return NF_DROP;
4971

4972 4973 4974
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4975
			return NF_DROP_ERR(-ECONNREFUSED);
4976 4977 4978 4979 4980 4981

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4982
			return NF_DROP;
4983 4984
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4985
			return NF_DROP_ERR(-ECONNREFUSED);
4986 4987

		if (sel_netnode_sid(addrp, family, &node_sid))
4988
			return NF_DROP;
4989 4990
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4991
			return NF_DROP_ERR(-ECONNREFUSED);
4992
	}
4993

4994
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4995 4996
}

4997
static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4998 4999 5000 5001
					   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
5002
{
5003
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
5004 5005 5006
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5007
static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5008 5009 5010 5011
					   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
5012
{
5013
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
5014 5015 5016 5017 5018 5019 5020 5021 5022
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

5023
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
5024 5025 5026
	if (err)
		return err;

5027
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5028 5029 5030 5031 5032 5033 5034
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
5035
	u32 sid;
L
Linus Torvalds 已提交
5036

J
James Morris 已提交
5037
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5038 5039 5040
	if (!isec)
		return -ENOMEM;

5041
	sid = task_sid(task);
L
Linus Torvalds 已提交
5042
	isec->sclass = sclass;
5043
	isec->sid = sid;
L
Linus Torvalds 已提交
5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059
	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
5060
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078
	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,
5079
			u32 perms)
L
Linus Torvalds 已提交
5080 5081
{
	struct ipc_security_struct *isec;
5082
	struct common_audit_data ad;
5083
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5084 5085 5086

	isec = ipc_perms->security;

5087
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5088 5089
	ad.u.ipc_id = ipc_perms->key;

5090
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102 5103 5104 5105 5106
}

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;
5107
	struct common_audit_data ad;
5108
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5109 5110 5111 5112 5113 5114 5115 5116
	int rc;

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

	isec = msq->q_perm.security;

5117
	ad.type = LSM_AUDIT_DATA_IPC;
5118
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5119

5120
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136
			  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;
5137
	struct common_audit_data ad;
5138
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5139 5140 5141

	isec = msq->q_perm.security;

5142
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5143 5144
	ad.u.ipc_id = msq->q_perm.key;

5145
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5146 5147 5148 5149 5150 5151 5152 5153
			    MSGQ__ASSOCIATE, &ad);
}

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

5154
	switch (cmd) {
L
Linus Torvalds 已提交
5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172
	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;
	}

5173
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5174 5175 5176 5177 5178 5179 5180
	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;
5181
	struct common_audit_data ad;
5182
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195
	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
		 */
5196
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5197
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5198 5199 5200 5201
		if (rc)
			return rc;
	}

5202
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5203 5204 5205
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5206
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5207 5208 5209
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5210 5211
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5212 5213
	if (!rc)
		/* Can the message be put in the queue? */
5214 5215
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5216 5217 5218 5219 5220 5221 5222 5223 5224 5225

	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;
5226
	struct common_audit_data ad;
5227
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5228 5229 5230 5231 5232
	int rc;

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

5233
	ad.type = LSM_AUDIT_DATA_IPC;
5234
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5235

5236
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5237 5238
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5239
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5240 5241 5242 5243 5244 5245 5246 5247
				  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;
5248
	struct common_audit_data ad;
5249
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5250 5251 5252 5253 5254 5255 5256 5257
	int rc;

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

	isec = shp->shm_perm.security;

5258
	ad.type = LSM_AUDIT_DATA_IPC;
5259
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5260

5261
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277
			  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;
5278
	struct common_audit_data ad;
5279
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5280 5281 5282

	isec = shp->shm_perm.security;

5283
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5284 5285
	ad.u.ipc_id = shp->shm_perm.key;

5286
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5287 5288 5289 5290 5291 5292 5293 5294 5295
			    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;

5296
	switch (cmd) {
L
Linus Torvalds 已提交
5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318
	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;
	}

5319
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332
	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;

5333
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5334 5335 5336 5337 5338 5339
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5340
	struct common_audit_data ad;
5341
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5342 5343 5344 5345 5346 5347 5348 5349
	int rc;

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

	isec = sma->sem_perm.security;

5350
	ad.type = LSM_AUDIT_DATA_IPC;
5351
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5352

5353
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369
			  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;
5370
	struct common_audit_data ad;
5371
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5372 5373 5374

	isec = sma->sem_perm.security;

5375
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5376 5377
	ad.u.ipc_id = sma->sem_perm.key;

5378
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5379 5380 5381 5382 5383 5384 5385 5386 5387
			    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;

5388
	switch (cmd) {
L
Linus Torvalds 已提交
5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419
	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;
	}

5420
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433
	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;

5434
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446 5447 5448 5449
}

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;

5450
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5451 5452
}

5453 5454 5455 5456 5457 5458
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5459
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5460 5461 5462 5463 5464 5465
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5466
			       char *name, char **value)
L
Linus Torvalds 已提交
5467
{
5468
	const struct task_security_struct *__tsec;
5469
	u32 sid;
L
Linus Torvalds 已提交
5470
	int error;
5471
	unsigned len;
L
Linus Torvalds 已提交
5472 5473

	if (current != p) {
5474
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5475 5476 5477 5478
		if (error)
			return error;
	}

5479 5480
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5481 5482

	if (!strcmp(name, "current"))
5483
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5484
	else if (!strcmp(name, "prev"))
5485
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5486
	else if (!strcmp(name, "exec"))
5487
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5488
	else if (!strcmp(name, "fscreate"))
5489
		sid = __tsec->create_sid;
5490
	else if (!strcmp(name, "keycreate"))
5491
		sid = __tsec->keycreate_sid;
5492
	else if (!strcmp(name, "sockcreate"))
5493
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5494
	else
5495 5496
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5497 5498 5499 5500

	if (!sid)
		return 0;

5501 5502 5503 5504
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5505 5506 5507 5508

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5509 5510 5511 5512 5513 5514
}

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
5515
	struct task_struct *tracer;
D
David Howells 已提交
5516 5517
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532
	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"))
5533
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5534
	else if (!strcmp(name, "fscreate"))
5535
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5536
	else if (!strcmp(name, "keycreate"))
5537
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5538
	else if (!strcmp(name, "sockcreate"))
5539
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5540
	else if (!strcmp(name, "current"))
5541
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552
	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--;
		}
5553
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5554
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569
			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);

5570
				return error;
5571
			}
5572 5573 5574
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5575 5576 5577 5578
		if (error)
			return error;
	}

D
David Howells 已提交
5579 5580 5581 5582
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5583 5584 5585
	/* 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
5586
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5587 5588
	   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
5589 5590
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5591
		tsec->exec_sid = sid;
D
David Howells 已提交
5592
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5593
		tsec->create_sid = sid;
D
David Howells 已提交
5594
	} else if (!strcmp(name, "keycreate")) {
5595 5596
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5597
			goto abort_change;
5598
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5599
	} else if (!strcmp(name, "sockcreate")) {
5600
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5601 5602
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5603
		if (sid == 0)
D
David Howells 已提交
5604 5605 5606 5607
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5608
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5609 5610 5611
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5612
		}
L
Linus Torvalds 已提交
5613 5614 5615

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5616
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5617
		if (error)
D
David Howells 已提交
5618
			goto abort_change;
L
Linus Torvalds 已提交
5619 5620 5621

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5622
		ptsid = 0;
5623
		rcu_read_lock();
5624
		tracer = ptrace_parent(p);
D
David Howells 已提交
5625 5626
		if (tracer)
			ptsid = task_sid(tracer);
5627
		rcu_read_unlock();
D
David Howells 已提交
5628 5629 5630 5631

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5632
			if (error)
D
David Howells 已提交
5633
				goto abort_change;
L
Linus Torvalds 已提交
5634 5635
		}

D
David Howells 已提交
5636 5637 5638 5639 5640 5641 5642
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5643
	return size;
D
David Howells 已提交
5644 5645 5646 5647

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5648 5649
}

5650 5651 5652 5653 5654
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5655 5656 5657 5658 5659
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5660
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5661
{
5662
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5663 5664
}

5665 5666
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5667
	kfree(secdata);
5668 5669
}

5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695
/*
 *	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;
}
5696 5697
#ifdef CONFIG_KEYS

D
David Howells 已提交
5698
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5699
			     unsigned long flags)
5700
{
D
David Howells 已提交
5701
	const struct task_security_struct *tsec;
5702 5703 5704 5705 5706 5707
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5708 5709 5710
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5711
	else
D
David Howells 已提交
5712
		ksec->sid = tsec->sid;
5713

5714
	k->security = ksec;
5715 5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726
	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
5727 5728
				  const struct cred *cred,
				  key_perm_t perm)
5729 5730 5731
{
	struct key *key;
	struct key_security_struct *ksec;
5732
	u32 sid;
5733 5734 5735 5736 5737 5738 5739

	/* 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
5740
	sid = cred_sid(cred);
5741 5742 5743 5744 5745

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5746 5747
}

5748 5749 5750 5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761
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;
}

5762 5763
#endif

L
Linus Torvalds 已提交
5764
static struct security_operations selinux_ops = {
5765 5766
	.name =				"selinux",

5767
	.ptrace_access_check =		selinux_ptrace_access_check,
5768
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5769
	.capget =			selinux_capget,
D
David Howells 已提交
5770
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5771 5772 5773 5774 5775 5776 5777 5778
	.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,

5779 5780 5781
	.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
5782 5783 5784 5785 5786
	.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,
5787
	.sb_remount =			selinux_sb_remount,
5788
	.sb_kern_mount =		selinux_sb_kern_mount,
5789
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5790 5791 5792
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5793
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5794
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5795 5796
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5797
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5798 5799 5800

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5801
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819
	.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,
5820 5821 5822
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5823
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5824 5825 5826 5827 5828

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5829 5830
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5831 5832 5833 5834 5835 5836 5837
	.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,

5838
	.file_open =			selinux_file_open,
5839

L
Linus Torvalds 已提交
5840
	.task_create =			selinux_task_create,
5841
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5842
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5843
	.cred_prepare =			selinux_cred_prepare,
5844
	.cred_transfer =		selinux_cred_transfer,
5845 5846
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5847
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5848 5849
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5850
	.task_getsid =			selinux_task_getsid,
5851
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5852
	.task_setnice =			selinux_task_setnice,
5853
	.task_setioprio =		selinux_task_setioprio,
5854
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5855 5856 5857
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5858
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5859 5860
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5861
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5862 5863

	.ipc_permission =		selinux_ipc_permission,
5864
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881

	.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,

5882 5883
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5884 5885 5886 5887
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5888
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5889

5890 5891
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5892

5893
	.ismaclabel =			selinux_ismaclabel,
5894
	.secid_to_secctx =		selinux_secid_to_secctx,
5895
	.secctx_to_secid =		selinux_secctx_to_secid,
5896
	.release_secctx =		selinux_release_secctx,
5897 5898 5899
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5900

5901
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912 5913 5914 5915 5916 5917
	.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
5918 5919
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5920 5921
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5922
	.sk_clone_security =		selinux_sk_clone_security,
5923
	.sk_getsecid =			selinux_sk_getsecid,
5924 5925 5926
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5927
	.inet_conn_established =	selinux_inet_conn_established,
5928 5929 5930
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5931
	.req_classify_flow =		selinux_req_classify_flow,
5932 5933
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5934
	.tun_dev_create =		selinux_tun_dev_create,
5935
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5936
	.tun_dev_attach =		selinux_tun_dev_attach,
5937
	.tun_dev_open =			selinux_tun_dev_open,
5938
	.skb_owned_by =			selinux_skb_owned_by,
5939 5940 5941 5942 5943

#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
5944
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5945 5946
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5947
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5948
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5949
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5950 5951
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5952
#endif
5953 5954

#ifdef CONFIG_KEYS
5955 5956 5957
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5958
	.key_getsecurity =		selinux_key_getsecurity,
5959
#endif
5960 5961 5962 5963 5964 5965 5966

#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
5967 5968 5969 5970
};

static __init int selinux_init(void)
{
5971 5972 5973 5974 5975
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5976 5977 5978 5979 5980 5981 5982 5983
	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
5984
	cred_init_security();
L
Linus Torvalds 已提交
5985

5986 5987
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5988 5989
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5990
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5991 5992
	avc_init();

5993
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5994 5995
		panic("SELinux: Unable to register with kernel.\n");

5996
	if (selinux_enforcing)
5997
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5998
	else
5999
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6000

L
Linus Torvalds 已提交
6001 6002 6003
	return 0;
}

6004 6005 6006 6007 6008
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
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void selinux_complete_init(void)
{
6011
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
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	/* Set up any superblocks initialized prior to the policy load. */
6014
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6015
	iterate_supers(delayed_superblock_init, NULL);
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}

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

6022
#if defined(CONFIG_NETFILTER)
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6024 6025 6026 6027
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
6028
		.pf =		NFPROTO_IPV4,
6029 6030 6031 6032 6033 6034
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
6035
		.pf =		NFPROTO_IPV4,
6036 6037
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6038 6039 6040 6041
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6042
		.pf =		NFPROTO_IPV4,
6043 6044
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6045
	}
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};

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

6050 6051 6052 6053
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6054
		.pf =		NFPROTO_IPV6,
6055 6056 6057 6058 6059 6060
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6061
		.pf =		NFPROTO_IPV6,
6062 6063 6064
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
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};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
6075 6076 6077

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

6078 6079 6080
	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
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6083 6084 6085
	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
6086
#endif	/* IPV6 */
6087

L
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out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6097
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6098

6099
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
6100
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6101
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
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6102 6103 6104 6105
#endif	/* IPV6 */
}
#endif

6106
#else /* CONFIG_NETFILTER */
L
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6107 6108 6109 6110 6111

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6112
#endif /* CONFIG_NETFILTER */
L
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6113 6114

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6115 6116
static int selinux_disabled;

L
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6117 6118 6119 6120 6121 6122 6123 6124 6125 6126 6127 6128 6129 6130 6131
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;
6132
	selinux_enabled = 0;
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Linus Torvalds 已提交
6133

6134
	reset_security_ops();
L
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6135

6136 6137 6138
	/* Try to destroy the avc node cache */
	avc_disable();

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6139 6140 6141 6142 6143 6144 6145 6146 6147
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif