hooks.c 151.1 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;
	if (!strict_strtoul(str, 0, &enforcing))
		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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static struct kmem_cache *sel_inode_cache;
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/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
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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 2128 2129 2130

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

2140
	ad.type = LSM_AUDIT_DATA_PATH;
2141
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2142

2143 2144
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2145
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2146

2147 2148
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2149 2150 2151 2152 2153
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2154
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2155 2156 2157 2158
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2159
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2160 2161 2162 2163
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181
		/* 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();
2182
			tracer = ptrace_parent(current);
2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196
			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
2197

2198 2199
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2200 2201 2202 2203 2204
	}

	return 0;
}

2205
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2206
{
2207
	const struct task_security_struct *tsec = current_security();
2208
	u32 sid, osid;
L
Linus Torvalds 已提交
2209 2210
	int atsecure = 0;

2211 2212 2213 2214
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2215 2216 2217
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2218
		atsecure = avc_has_perm(osid, sid,
2219 2220
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2221 2222
	}

2223
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2224 2225
}

A
Al Viro 已提交
2226 2227 2228 2229 2230
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
2231
/* Derived from fs/exec.c:flush_old_files. */
2232 2233
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2234 2235
{
	struct file *file, *devnull = NULL;
2236
	struct tty_struct *tty;
2237
	int drop_tty = 0;
A
Al Viro 已提交
2238
	unsigned n;
L
Linus Torvalds 已提交
2239

2240
	tty = get_current_tty();
L
Linus Torvalds 已提交
2241
	if (tty) {
N
Nick Piggin 已提交
2242
		spin_lock(&tty_files_lock);
2243
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2244
			struct tty_file_private *file_priv;
2245

L
Linus Torvalds 已提交
2246
			/* Revalidate access to controlling tty.
2247 2248 2249 2250
			   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
2251 2252 2253
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2254
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2255
				drop_tty = 1;
L
Linus Torvalds 已提交
2256
		}
N
Nick Piggin 已提交
2257
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2258
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2259
	}
2260 2261 2262
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2263 2264

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2265 2266 2267
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2268

A
Al Viro 已提交
2269
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2270 2271 2272 2273 2274 2275 2276
	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
2277
		fput(devnull);
L
Linus Torvalds 已提交
2278 2279
}

2280 2281 2282 2283
/*
 * 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
2284
{
2285 2286 2287
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2288

2289 2290 2291
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2292

2293 2294
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2295

2296 2297
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2298

2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311
	/* 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) {
2312 2313
		/* protect against do_prlimit() */
		task_lock(current);
2314 2315 2316 2317
		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
2318
		}
2319 2320
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2321 2322 2323 2324
	}
}

/*
2325 2326
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2327
 */
2328
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2329
{
2330
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2331
	struct itimerval itimer;
2332
	u32 osid, sid;
L
Linus Torvalds 已提交
2333 2334
	int rc, i;

2335 2336 2337 2338
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2339 2340
		return;

2341 2342 2343 2344 2345 2346 2347 2348
	/* 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
2349 2350 2351 2352 2353
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2354 2355 2356 2357 2358
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2359 2360 2361
		spin_unlock_irq(&current->sighand->siglock);
	}

2362 2363
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2364
	read_lock(&tasklist_lock);
2365
	__wake_up_parent(current, current->real_parent);
2366
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390
}

/* 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)
{
2391 2392 2393
	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) ||
2394 2395
		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
2396 2397 2398 2399 2400 2401 2402
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2403
	} else
L
Linus Torvalds 已提交
2404 2405 2406 2407 2408
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2409 2410
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2411 2412 2413 2414 2415 2416
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2417
	} else
2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429
		*first = 0;

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

2430
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2431 2432 2433 2434
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2435
	int open_quote = 0;
L
Linus Torvalds 已提交
2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450

	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 {
2451 2452 2453 2454
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2455 2456 2457
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2458
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2459 2460 2461 2462 2463 2464 2465
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2466
	strcpy(in_save, nosec_save);
2467
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2468 2469 2470 2471
out:
	return rc;
}

2472 2473 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
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;

2507
		if (flags[i] == SBLABEL_MNT)
2508 2509
			continue;
		len = strlen(mount_options[i]);
2510 2511
		rc = security_context_to_sid(mount_options[i], len, &sid,
					     GFP_KERNEL);
2512 2513
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2514 2515
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2516 2517 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
			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 "
2553 2554
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2555 2556 2557
	goto out_free_opts;
}

2558
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2559
{
2560
	const struct cred *cred = current_cred();
2561
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2562 2563 2564 2565 2566 2567
	int rc;

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

2568 2569 2570 2571
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2572
	ad.type = LSM_AUDIT_DATA_DENTRY;
2573
	ad.u.dentry = sb->s_root;
2574
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2575 2576
}

2577
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2578
{
2579
	const struct cred *cred = current_cred();
2580
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2581

2582
	ad.type = LSM_AUDIT_DATA_DENTRY;
2583
	ad.u.dentry = dentry->d_sb->s_root;
2584
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2585 2586
}

A
Al Viro 已提交
2587
static int selinux_mount(const char *dev_name,
2588
			 struct path *path,
A
Al Viro 已提交
2589
			 const char *type,
2590 2591
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2592
{
2593
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2594 2595

	if (flags & MS_REMOUNT)
2596
		return superblock_has_perm(cred, path->dentry->d_sb,
2597
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2598
	else
E
Eric Paris 已提交
2599
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2600 2601 2602 2603
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2604
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2605

2606
	return superblock_has_perm(cred, mnt->mnt_sb,
2607
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621
}

/* 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);
}

2622 2623 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
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);
}

2656
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2657 2658
				       const struct qstr *qstr,
				       const char **name,
2659
				       void **value, size_t *len)
2660
{
2661
	const struct task_security_struct *tsec = current_security();
2662 2663
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2664
	u32 sid, newsid, clen;
2665
	int rc;
2666
	char *context;
2667 2668 2669 2670

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

2671 2672 2673
	sid = tsec->sid;
	newsid = tsec->create_sid;

2674 2675 2676
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2677
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2678
		rc = security_transition_sid(sid, dsec->sid,
2679
					     inode_mode_to_security_class(inode->i_mode),
2680
					     qstr, &newsid);
2681 2682 2683 2684
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2685
			       __func__,
2686 2687 2688 2689 2690
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2691
	/* Possibly defer initialization to selinux_complete_init. */
2692
	if (sbsec->flags & SE_SBINITIALIZED) {
2693 2694 2695 2696 2697
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2698

2699
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2700 2701
		return -EOPNOTSUPP;

2702 2703
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2704

2705
	if (value && len) {
2706
		rc = security_sid_to_context_force(newsid, &context, &clen);
2707
		if (rc)
2708 2709 2710
			return rc;
		*value = context;
		*len = clen;
2711 2712 2713 2714 2715
	}

	return 0;
}

A
Al Viro 已提交
2716
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735
{
	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);
}

2736
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2737 2738 2739 2740 2741 2742 2743 2744 2745
{
	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
2746
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2747 2748 2749 2750 2751
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2752
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2753 2754 2755 2756 2757 2758
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2759 2760
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2761
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2762 2763 2764 2765
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2766
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2767

E
Eric Paris 已提交
2768
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2769 2770
}

2771 2772 2773
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2774
{
2775
	struct common_audit_data ad;
2776 2777 2778
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2779
	ad.type = LSM_AUDIT_DATA_INODE;
2780 2781 2782 2783 2784 2785 2786 2787 2788
	ad.u.inode = inode;

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

2789
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2790
{
2791
	const struct cred *cred = current_cred();
2792 2793
	u32 perms;
	bool from_access;
2794
	unsigned flags = mask & MAY_NOT_BLOCK;
2795 2796 2797 2798 2799
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2800

2801
	from_access = mask & MAY_ACCESS;
2802 2803
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2804 2805
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2806 2807
		return 0;

2808
	validate_creds(cred);
2809

2810 2811
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2812 2813 2814

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

2815 2816 2817 2818 2819 2820 2821 2822 2823 2824
	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;

2825
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2826 2827 2828
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2829 2830 2831 2832
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2833
	const struct cred *cred = current_cred();
2834
	unsigned int ia_valid = iattr->ia_valid;
2835
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2836

2837 2838 2839 2840 2841 2842 2843
	/* 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
2844

2845 2846
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2847
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2848

2849
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2850 2851 2852
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2853 2854 2855 2856
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2857
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2858 2859 2860 2861
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2862

E
Eric Paris 已提交
2863
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2864 2865
}

2866
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2867
{
2868 2869
	const struct cred *cred = current_cred();

2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883
	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
2884
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2885 2886
}

2887 2888
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
2889 2890 2891 2892
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2893
	struct common_audit_data ad;
2894
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2895 2896
	int rc = 0;

2897 2898
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2899 2900

	sbsec = inode->i_sb->s_security;
2901
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2902 2903
		return -EOPNOTSUPP;

2904
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2905 2906
		return -EPERM;

2907
	ad.type = LSM_AUDIT_DATA_DENTRY;
2908
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2909

2910
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2911 2912 2913 2914
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

2915
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2916
	if (rc == -EINVAL) {
2917 2918 2919 2920 2921 2922 2923
		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 */
2924 2925 2926 2927 2928 2929 2930 2931 2932 2933
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2934 2935 2936 2937 2938
			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);

2939
			return rc;
2940
		}
2941 2942
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2943 2944 2945
	if (rc)
		return rc;

2946
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2947 2948 2949 2950
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2951
	rc = security_validate_transition(isec->sid, newsid, sid,
2952
					  isec->sclass);
L
Linus Torvalds 已提交
2953 2954 2955 2956 2957 2958 2959 2960 2961 2962
	if (rc)
		return rc;

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

2963
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2964
					const void *value, size_t size,
2965
					int flags)
L
Linus Torvalds 已提交
2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976
{
	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;
	}

2977
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2978
	if (rc) {
2979 2980 2981
		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
2982 2983 2984
		return;
	}

2985
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
2986
	isec->sid = newsid;
2987 2988
	isec->initialized = 1;

L
Linus Torvalds 已提交
2989 2990 2991
	return;
}

2992
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2993
{
2994 2995
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2996
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2997 2998
}

2999
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3000
{
3001 3002
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3003
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3004 3005
}

3006
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3007
{
3008 3009
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3010 3011 3012 3013 3014 3015

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

3016
/*
3017
 * Copy the inode security context value to the user.
3018 3019 3020
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3021
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3022
{
3023 3024 3025
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
3026
	struct inode_security_struct *isec = inode->i_security;
3027

3028 3029
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3030

3031 3032 3033 3034 3035 3036 3037 3038 3039
	/*
	 * 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.
	 */
3040
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3041
				SECURITY_CAP_NOAUDIT);
3042 3043 3044 3045 3046
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3047 3048 3049 3050 3051 3052 3053 3054 3055 3056
	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
3057 3058 3059
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3060
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071
{
	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;

3072
	rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3073 3074 3075
	if (rc)
		return rc;

3076
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3077
	isec->sid = newsid;
3078
	isec->initialized = 1;
L
Linus Torvalds 已提交
3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089
	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;
}

3090 3091 3092 3093 3094 3095
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
3096 3097
/* file security operations */

3098
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3099
{
3100
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3101
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3102 3103 3104 3105 3106

	/* 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;

3107 3108
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3109 3110
}

3111 3112
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3113
	struct inode *inode = file_inode(file);
3114 3115 3116 3117
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3118
	if (!mask)
3119 3120 3121
		/* No permission to check.  Existence test. */
		return 0;

3122 3123
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3124
		/* No change since file_open check. */
3125 3126
		return 0;

3127 3128 3129
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142
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)
{
3143
	const struct cred *cred = current_cred();
3144
	int error = 0;
L
Linus Torvalds 已提交
3145

3146 3147 3148 3149 3150 3151 3152
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3153
	case FS_IOC_GETFLAGS:
3154
	/* fall through */
3155
	case FS_IOC_GETVERSION:
3156 3157
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3158

3159
	case FS_IOC_SETFLAGS:
3160
	/* fall through */
3161
	case FS_IOC_SETVERSION:
3162 3163 3164 3165 3166 3167 3168 3169 3170
		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
3171

3172 3173
	case KDSKBENT:
	case KDSKBSENT:
3174 3175
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3176 3177 3178 3179 3180 3181 3182 3183 3184
		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
3185 3186
}

3187 3188
static int default_noexec;

L
Linus Torvalds 已提交
3189 3190
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3191
	const struct cred *cred = current_cred();
D
David Howells 已提交
3192
	int rc = 0;
3193

3194 3195
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3196 3197 3198 3199 3200
		/*
		 * 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
3201
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3202
		if (rc)
D
David Howells 已提交
3203
			goto error;
L
Linus Torvalds 已提交
3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216
	}

	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;

3217
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3218
	}
D
David Howells 已提交
3219 3220 3221

error:
	return rc;
L
Linus Torvalds 已提交
3222 3223
}

3224
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3225
{
3226 3227 3228 3229 3230 3231
	int rc;

	/* do DAC check on address space usage */
	rc = cap_mmap_addr(addr);
	if (rc)
		return rc;
L
Linus Torvalds 已提交
3232

3233
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3234
		u32 sid = current_sid();
3235 3236
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3237 3238
	}

3239
	return rc;
3240
}
L
Linus Torvalds 已提交
3241

3242 3243 3244
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255
	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)
{
3256
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3257 3258 3259 3260

	if (selinux_checkreqprot)
		prot = reqprot;

3261 3262
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3263
		int rc = 0;
3264 3265
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3266
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3267 3268 3269
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3270
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3271 3272 3273 3274 3275 3276 3277 3278
		} 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
3279
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3280
		}
3281 3282 3283
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3284 3285 3286 3287 3288 3289

	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)
{
3290 3291 3292
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3293 3294 3295 3296 3297
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3298
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3299 3300 3301
	int err = 0;

	switch (cmd) {
3302 3303
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3304
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3305
			break;
3306 3307 3308 3309 3310 3311 3312
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3313
	case F_GETOWNER_UIDS:
3314
		/* Just check FD__USE permission */
3315
		err = file_has_perm(cred, file, 0);
3316 3317 3318 3319
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3320
#if BITS_PER_LONG == 32
3321 3322 3323
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3324
#endif
3325
		err = file_has_perm(cred, file, FILE__LOCK);
3326
		break;
L
Linus Torvalds 已提交
3327 3328 3329 3330 3331 3332 3333 3334 3335 3336
	}

	return err;
}

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

	fsec = file->f_security;
3337
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3338 3339 3340 3341 3342 3343 3344

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3345
	struct file *file;
3346
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3347 3348 3349 3350
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3351
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3352 3353 3354 3355 3356 3357 3358 3359

	fsec = file->f_security;

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

3360
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3361 3362 3363 3364 3365
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3366 3367 3368
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3369 3370
}

3371
static int selinux_file_open(struct file *file, const struct cred *cred)
3372 3373 3374
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3375

3376
	fsec = file->f_security;
A
Al Viro 已提交
3377
	isec = file_inode(file)->i_security;
3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394
	/*
	 * 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.
	 */
3395
	return file_path_has_perm(cred, file, open_file_to_av(file));
3396 3397
}

L
Linus Torvalds 已提交
3398 3399 3400 3401
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3402
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3403 3404
}

3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419
/*
 * 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
3420 3421 3422 3423
/*
 * 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
3424
{
D
David Howells 已提交
3425
	struct task_security_struct *tsec = cred->security;
3426

3427 3428 3429 3430 3431
	/*
	 * 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);
3432
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3433 3434
	kfree(tsec);
}
L
Linus Torvalds 已提交
3435

D
David Howells 已提交
3436 3437 3438 3439 3440 3441 3442 3443
/*
 * 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
3444

D
David Howells 已提交
3445
	old_tsec = old->security;
L
Linus Torvalds 已提交
3446

D
David Howells 已提交
3447 3448 3449
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3450

D
David Howells 已提交
3451
	new->security = tsec;
L
Linus Torvalds 已提交
3452 3453 3454
	return 0;
}

3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465
/*
 * 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;
}

3466 3467 3468 3469 3470 3471 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
/*
 * 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;
3507
	return ret;
3508 3509
}

3510
static int selinux_kernel_module_request(char *kmod_name)
3511
{
3512 3513 3514 3515 3516
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3517
	ad.type = LSM_AUDIT_DATA_KMOD;
3518 3519 3520 3521
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3522 3523
}

L
Linus Torvalds 已提交
3524 3525
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3526
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3527 3528 3529 3530
}

static int selinux_task_getpgid(struct task_struct *p)
{
3531
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3532 3533 3534 3535
}

static int selinux_task_getsid(struct task_struct *p)
{
3536
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3537 3538
}

3539 3540
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3541
	*secid = task_sid(p);
3542 3543
}

L
Linus Torvalds 已提交
3544 3545 3546 3547
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3548
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3549 3550 3551
	if (rc)
		return rc;

3552
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3553 3554
}

3555 3556
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3557 3558
	int rc;

3559
	rc = cap_task_setioprio(p, ioprio);
3560 3561 3562
	if (rc)
		return rc;

3563
	return current_has_perm(p, PROCESS__SETSCHED);
3564 3565
}

3566 3567
static int selinux_task_getioprio(struct task_struct *p)
{
3568
	return current_has_perm(p, PROCESS__GETSCHED);
3569 3570
}

3571 3572
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3573
{
3574
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3575 3576 3577 3578

	/* 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
3579
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3580
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3581
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3582 3583 3584 3585

	return 0;
}

3586
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3587
{
3588 3589
	int rc;

3590
	rc = cap_task_setscheduler(p);
3591 3592 3593
	if (rc)
		return rc;

3594
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3595 3596 3597 3598
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3599
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3600 3601
}

3602 3603
static int selinux_task_movememory(struct task_struct *p)
{
3604
	return current_has_perm(p, PROCESS__SETSCHED);
3605 3606
}

3607 3608
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3609 3610 3611 3612 3613 3614 3615 3616
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3617
	if (secid)
3618 3619
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3620
	else
3621
		rc = current_has_perm(p, perm);
3622
	return rc;
L
Linus Torvalds 已提交
3623 3624 3625 3626
}

static int selinux_task_wait(struct task_struct *p)
{
3627
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3628 3629 3630 3631 3632 3633
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3634
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3635

3636
	isec->sid = sid;
L
Linus Torvalds 已提交
3637 3638 3639 3640
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3641
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3642
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3643 3644 3645 3646
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3647
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3648 3649 3650 3651 3652 3653 3654 3655
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3656 3657
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3658 3659
	ret = 0;

3660 3661 3662
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3663
	switch (ih->protocol) {
3664 3665
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3666

3667 3668
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3669 3670 3671 3672 3673 3674

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

3675 3676
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3677
		break;
3678 3679 3680 3681 3682 3683 3684 3685
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3686
		offset += ihlen;
3687
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3688
		if (uh == NULL)
3689
			break;
L
Linus Torvalds 已提交
3690

3691 3692
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3693 3694
		break;
	}
L
Linus Torvalds 已提交
3695

J
James Morris 已提交
3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706
	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;

3707 3708
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3709
		break;
3710
	}
J
James Morris 已提交
3711

3712 3713 3714
	default:
		break;
	}
L
Linus Torvalds 已提交
3715 3716 3717 3718 3719 3720 3721
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3722
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3723
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3724 3725 3726 3727
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3728
	__be16 frag_off;
L
Linus Torvalds 已提交
3729

3730
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3731 3732 3733 3734
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3735 3736
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3737 3738 3739 3740
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3741
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3742 3743 3744
	if (offset < 0)
		goto out;

3745 3746 3747
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3748 3749
	switch (nexthdr) {
	case IPPROTO_TCP: {
3750
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3751 3752 3753 3754 3755

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

3756 3757
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3758 3759 3760 3761 3762 3763 3764 3765 3766 3767
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3768 3769
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3770 3771 3772
		break;
	}

J
James Morris 已提交
3773 3774 3775 3776 3777 3778 3779
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3780 3781
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3782
		break;
3783
	}
J
James Morris 已提交
3784

L
Linus Torvalds 已提交
3785 3786 3787 3788 3789 3790 3791 3792 3793 3794
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3795
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3796
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3797
{
3798 3799
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3800

3801
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3802
	case PF_INET:
3803
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3804 3805
		if (ret)
			goto parse_error;
3806 3807
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3808
		goto okay;
L
Linus Torvalds 已提交
3809 3810 3811

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3812
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3813 3814
		if (ret)
			goto parse_error;
3815 3816
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3817
		goto okay;
L
Linus Torvalds 已提交
3818 3819
#endif	/* IPV6 */
	default:
3820 3821
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3822 3823
	}

3824 3825 3826 3827
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3828
	return ret;
3829 3830 3831 3832 3833

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3834 3835
}

3836
/**
3837
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3838
 * @skb: the packet
3839
 * @family: protocol family
3840
 * @sid: the packet's peer label SID
3841 3842
 *
 * Description:
3843 3844 3845 3846 3847 3848
 * 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.
3849 3850
 *
 */
3851
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3852
{
3853
	int err;
3854 3855
	u32 xfrm_sid;
	u32 nlbl_sid;
3856
	u32 nlbl_type;
3857

3858
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3859 3860 3861 3862 3863
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3864

3865 3866 3867 3868 3869
	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");
3870
		return -EACCES;
3871
	}
3872 3873

	return 0;
3874 3875
}

3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899
/**
 * 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
3900
/* socket security operations */
3901

3902 3903
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3904
{
3905 3906 3907 3908 3909 3910 3911
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3912 3913
}

3914
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3915
{
3916
	struct sk_security_struct *sksec = sk->sk_security;
3917
	struct common_audit_data ad;
3918
	struct lsm_network_audit net = {0,};
3919
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3920

3921 3922
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3923

3924
	ad.type = LSM_AUDIT_DATA_NET;
3925 3926
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3927

3928
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3929 3930 3931 3932 3933
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3934
	const struct task_security_struct *tsec = current_security();
3935
	u32 newsid;
3936
	u16 secclass;
3937
	int rc;
L
Linus Torvalds 已提交
3938 3939

	if (kern)
3940
		return 0;
3941 3942

	secclass = socket_type_to_security_class(family, type, protocol);
3943 3944 3945 3946
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3947
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3948 3949
}

V
Venkat Yekkirala 已提交
3950 3951
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3952
{
3953
	const struct task_security_struct *tsec = current_security();
3954
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3955
	struct sk_security_struct *sksec;
3956 3957
	int err = 0;

3958 3959
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3960 3961
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3962 3963 3964 3965 3966
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3967

L
Linus Torvalds 已提交
3968 3969
	isec->initialized = 1;

3970 3971 3972
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3973
		sksec->sclass = isec->sclass;
3974
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3975 3976
	}

V
Venkat Yekkirala 已提交
3977
	return err;
L
Linus Torvalds 已提交
3978 3979 3980 3981 3982 3983 3984 3985
}

/* 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)
{
3986
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3987 3988 3989
	u16 family;
	int err;

3990
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3991 3992 3993 3994 3995
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3996 3997
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3998
	 */
3999
	family = sk->sk_family;
L
Linus Torvalds 已提交
4000 4001
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4002
		struct sk_security_struct *sksec = sk->sk_security;
4003
		struct common_audit_data ad;
4004
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4005 4006 4007
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4008
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019

		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;
		}

4020 4021 4022
		if (snum) {
			int low, high;

4023
			inet_get_local_port_range(sock_net(sk), &low, &high);
4024 4025

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
4026 4027
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4028 4029
				if (err)
					goto out;
4030
				ad.type = LSM_AUDIT_DATA_NET;
4031 4032 4033
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4034 4035
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4036 4037 4038 4039
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4040
		}
4041

4042
		switch (sksec->sclass) {
4043
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4044 4045
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4046

4047
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4048 4049
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4050 4051 4052 4053 4054

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4055 4056 4057 4058
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4059

4060
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4061 4062
		if (err)
			goto out;
4063

4064
		ad.type = LSM_AUDIT_DATA_NET;
4065 4066 4067
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4068 4069

		if (family == PF_INET)
4070
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4071
		else
4072
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4073

4074 4075
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4076 4077 4078 4079 4080 4081 4082 4083 4084
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4085
	struct sock *sk = sock->sk;
4086
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4087 4088
	int err;

4089
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4090 4091 4092 4093
	if (err)
		return err;

	/*
J
James Morris 已提交
4094
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4095
	 */
4096 4097
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4098
		struct common_audit_data ad;
4099
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4100 4101 4102
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4103
		u32 sid, perm;
L
Linus Torvalds 已提交
4104 4105 4106

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4107
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4108 4109 4110 4111
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4112
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4113 4114 4115 4116
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4117
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4118 4119 4120
		if (err)
			goto out;

4121
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4122 4123
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4124
		ad.type = LSM_AUDIT_DATA_NET;
4125 4126 4127
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4128
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4129 4130 4131 4132
		if (err)
			goto out;
	}

4133 4134
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4135 4136 4137 4138 4139 4140
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4141
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4142 4143 4144 4145 4146 4147 4148 4149
}

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

4150
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4151 4152 4153 4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164
	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,
4165
				  int size)
L
Linus Torvalds 已提交
4166
{
4167
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4168 4169 4170 4171 4172
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4173
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4174 4175 4176 4177
}

static int selinux_socket_getsockname(struct socket *sock)
{
4178
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4179 4180 4181 4182
}

static int selinux_socket_getpeername(struct socket *sock)
{
4183
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4184 4185
}

4186
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4187
{
4188 4189
	int err;

4190
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4191 4192 4193 4194
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4195 4196 4197 4198 4199
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4200
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4201 4202 4203 4204
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4205
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4206 4207
}

4208 4209
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4210 4211
					      struct sock *newsk)
{
4212 4213
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4214
	struct sk_security_struct *sksec_new = newsk->sk_security;
4215
	struct common_audit_data ad;
4216
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4217 4218
	int err;

4219
	ad.type = LSM_AUDIT_DATA_NET;
4220 4221
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4222

4223 4224
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4225 4226 4227 4228 4229
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4230 4231 4232 4233 4234
	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;
4235

4236 4237 4238 4239
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4240 4241 4242 4243 4244
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4245 4246
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4247
	struct common_audit_data ad;
4248
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4249

4250
	ad.type = LSM_AUDIT_DATA_NET;
4251 4252
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4253

4254 4255
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4256 4257
}

4258 4259
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4260
				    struct common_audit_data *ad)
4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280
{
	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);
}

4281
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4282
				       u16 family)
4283
{
4284
	int err = 0;
4285 4286
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4287
	struct common_audit_data ad;
4288
	struct lsm_network_audit net = {0,};
4289 4290
	char *addrp;

4291
	ad.type = LSM_AUDIT_DATA_NET;
4292 4293 4294
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4295 4296 4297
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4298

4299
	if (selinux_secmark_enabled()) {
4300
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4301
				   PACKET__RECV, &ad);
4302 4303 4304
		if (err)
			return err;
	}
4305

4306 4307 4308 4309
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4310

4311 4312 4313 4314 4315
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4316
	int err;
4317
	struct sk_security_struct *sksec = sk->sk_security;
4318 4319
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4320
	struct common_audit_data ad;
4321
	struct lsm_network_audit net = {0,};
4322
	char *addrp;
4323 4324
	u8 secmark_active;
	u8 peerlbl_active;
4325 4326

	if (family != PF_INET && family != PF_INET6)
4327
		return 0;
4328 4329

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4330
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4331 4332
		family = PF_INET;

4333 4334 4335 4336
	/* 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. */
4337
	if (!selinux_policycap_netpeer)
4338 4339 4340
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4341
	peerlbl_active = selinux_peerlbl_enabled();
4342 4343 4344
	if (!secmark_active && !peerlbl_active)
		return 0;

4345
	ad.type = LSM_AUDIT_DATA_NET;
4346 4347 4348
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4349
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4350
	if (err)
4351
		return err;
4352

4353
	if (peerlbl_active) {
4354 4355 4356
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4357 4358
		if (err)
			return err;
4359
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4360
					       peer_sid, &ad);
4361 4362
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4363
			return err;
4364
		}
4365 4366
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4367
		if (err) {
4368
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4369 4370
			return err;
		}
4371 4372
	}

4373
	if (secmark_active) {
4374 4375 4376 4377 4378 4379
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4380
	return err;
L
Linus Torvalds 已提交
4381 4382
}

C
Catherine Zhang 已提交
4383 4384
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4385 4386 4387 4388
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4389
	struct sk_security_struct *sksec = sock->sk->sk_security;
4390
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4391

4392 4393
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4394
		peer_sid = sksec->peer_sid;
4395 4396
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4397

C
Catherine Zhang 已提交
4398
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4399
	if (err)
4400
		return err;
L
Linus Torvalds 已提交
4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416

	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;
}

4417
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4418
{
4419
	u32 peer_secid = SECSID_NULL;
4420
	u16 family;
C
Catherine Zhang 已提交
4421

4422 4423 4424 4425 4426
	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)
4427 4428 4429 4430 4431
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4432
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4433
	else if (skb)
4434
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4435

4436
out:
4437
	*secid = peer_secid;
4438 4439 4440
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4441 4442
}

A
Al Viro 已提交
4443
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4444
{
4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456
	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
4457 4458 4459 4460
}

static void selinux_sk_free_security(struct sock *sk)
{
4461 4462 4463 4464 4465
	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
4466 4467
}

4468
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4469
{
4470 4471
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4472

4473 4474 4475
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4476

4477
	selinux_netlbl_sk_security_reset(newsksec);
4478 4479
}

V
Venkat Yekkirala 已提交
4480
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4481
{
4482
	if (!sk)
V
Venkat Yekkirala 已提交
4483
		*secid = SECINITSID_ANY_SOCKET;
4484 4485
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4486

V
Venkat Yekkirala 已提交
4487
		*secid = sksec->sid;
4488
	}
4489 4490
}

4491
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4492 4493 4494 4495
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4496 4497 4498
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4499
	sksec->sclass = isec->sclass;
4500 4501
}

4502 4503
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4504 4505 4506
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4507
	u16 family = req->rsk_ops->family;
4508
	u32 connsid;
4509 4510
	u32 peersid;

4511
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4512 4513
	if (err)
		return err;
4514 4515 4516 4517 4518
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4519

4520
	return selinux_netlbl_inet_conn_request(req, family);
4521 4522
}

4523 4524
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4525 4526 4527 4528
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4529
	newsksec->peer_sid = req->peer_secid;
4530 4531 4532 4533
	/* 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. */
4534

P
Paul Moore 已提交
4535 4536
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4537
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4538 4539
}

4540
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4541
{
4542
	u16 family = sk->sk_family;
4543 4544
	struct sk_security_struct *sksec = sk->sk_security;

4545 4546 4547 4548 4549
	/* 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);
4550 4551
}

4552 4553 4554 4555 4556
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577
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);
}

4578 4579
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4580
{
4581
	fl->flowi_secid = req->secid;
4582 4583
}

4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601
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);
}

4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616
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);
}

4617
static int selinux_tun_dev_attach_queue(void *security)
4618
{
4619 4620 4621 4622 4623 4624 4625 4626 4627
	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;
4628 4629 4630 4631 4632 4633 4634 4635 4636
	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 */

4637
	sksec->sid = tunsec->sid;
4638
	sksec->sclass = SECCLASS_TUN_SOCKET;
4639 4640

	return 0;
4641 4642
}

4643
static int selinux_tun_dev_open(void *security)
4644
{
4645
	struct tun_security_struct *tunsec = security;
4646 4647 4648
	u32 sid = current_sid();
	int err;

4649
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4650 4651 4652 4653 4654 4655 4656
			   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;
4657
	tunsec->sid = sid;
4658 4659 4660 4661

	return 0;
}

L
Linus Torvalds 已提交
4662 4663 4664 4665 4666
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4667
	struct sk_security_struct *sksec = sk->sk_security;
4668

4669
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4670 4671 4672
		err = -EINVAL;
		goto out;
	}
4673
	nlh = nlmsg_hdr(skb);
4674

4675
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4676 4677
	if (err) {
		if (err == -EINVAL) {
4678
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4679 4680
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4681
				  nlh->nlmsg_type, sksec->sclass);
4682
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4683 4684 4685 4686 4687 4688 4689 4690 4691
				err = 0;
		}

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

4692
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4693 4694 4695 4696 4697 4698
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4699 4700
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4701
{
4702
	int err;
4703 4704
	char *addrp;
	u32 peer_sid;
4705
	struct common_audit_data ad;
4706
	struct lsm_network_audit net = {0,};
4707
	u8 secmark_active;
4708
	u8 netlbl_active;
4709
	u8 peerlbl_active;
4710

4711 4712
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4713

4714
	secmark_active = selinux_secmark_enabled();
4715
	netlbl_active = netlbl_enabled();
4716
	peerlbl_active = selinux_peerlbl_enabled();
4717 4718
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4719

4720 4721 4722
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4723
	ad.type = LSM_AUDIT_DATA_NET;
4724 4725 4726
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4727 4728 4729
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4730 4731 4732 4733 4734
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4735
			return NF_DROP;
4736 4737
		}
	}
4738 4739 4740 4741 4742 4743

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

4744 4745 4746 4747 4748 4749 4750 4751
	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;

4752 4753 4754
	return NF_ACCEPT;
}

4755
static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4756 4757 4758 4759 4760 4761 4762 4763 4764
					 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)
4765
static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4766 4767 4768 4769 4770 4771 4772 4773 4774
					 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 */

4775 4776 4777
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4778
	struct sock *sk;
4779 4780 4781 4782 4783 4784 4785 4786
	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 */
4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807
	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;
4808 4809 4810 4811 4812 4813 4814 4815 4816
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4817
static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4818 4819 4820 4821 4822 4823 4824 4825
					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);
}

4826 4827
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4828
						u16 family)
4829 4830 4831
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4832
	struct common_audit_data ad;
4833
	struct lsm_network_audit net = {0,};
4834 4835
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4836

4837 4838 4839 4840
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4841
	ad.type = LSM_AUDIT_DATA_NET;
4842 4843 4844
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4845 4846 4847
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4848
	if (selinux_secmark_enabled())
4849
		if (avc_has_perm(sksec->sid, skb->secmark,
4850
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4851
			return NF_DROP_ERR(-ECONNREFUSED);
4852

4853 4854
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4855 4856

	return NF_ACCEPT;
4857 4858
}

4859 4860
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4861
{
4862 4863
	u32 secmark_perm;
	u32 peer_sid;
4864
	struct sock *sk;
4865
	struct common_audit_data ad;
4866
	struct lsm_network_audit net = {0,};
4867 4868 4869
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4870

4871 4872 4873 4874
	/* 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. */
4875
	if (!selinux_policycap_netpeer)
4876
		return selinux_ip_postroute_compat(skb, ifindex, family);
4877 4878 4879 4880 4881 4882 4883 4884

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

	sk = skb->sk;

4885
#ifdef CONFIG_XFRM
4886 4887 4888 4889 4890
	/* 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
4891 4892 4893 4894 4895 4896 4897 4898
	 *       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))
4899
		return NF_ACCEPT;
4900
#endif
4901

4902
	if (sk == NULL) {
4903 4904 4905 4906
		/* 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. */
4907 4908
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4909
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4910
				return NF_DROP;
4911 4912
		} else {
			secmark_perm = PACKET__SEND;
4913
			peer_sid = SECINITSID_KERNEL;
4914
		}
4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928
	} 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;
4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947
		/* 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);
			}
		}
4948 4949 4950
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4951
	} else {
4952 4953
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4954 4955 4956 4957
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4958

4959
	ad.type = LSM_AUDIT_DATA_NET;
4960 4961 4962
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4963
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4964
		return NF_DROP;
4965

4966 4967 4968
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4969
			return NF_DROP_ERR(-ECONNREFUSED);
4970 4971 4972 4973 4974 4975

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4976
			return NF_DROP;
4977 4978
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4979
			return NF_DROP_ERR(-ECONNREFUSED);
4980 4981

		if (sel_netnode_sid(addrp, family, &node_sid))
4982
			return NF_DROP;
4983 4984
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4985
			return NF_DROP_ERR(-ECONNREFUSED);
4986
	}
4987

4988
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4989 4990
}

4991
static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4992 4993 4994 4995
					   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
4996
{
4997
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4998 4999 5000
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5001
static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5002 5003 5004 5005
					   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
5006
{
5007
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
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5008 5009 5010 5011 5012 5013 5014 5015 5016
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

5017
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
5018 5019 5020
	if (err)
		return err;

5021
	return selinux_nlmsg_perm(sk, skb);
L
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5022 5023 5024 5025 5026 5027 5028
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
5029
	u32 sid;
L
Linus Torvalds 已提交
5030

J
James Morris 已提交
5031
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
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5032 5033 5034
	if (!isec)
		return -ENOMEM;

5035
	sid = task_sid(task);
L
Linus Torvalds 已提交
5036
	isec->sclass = sclass;
5037
	isec->sid = sid;
L
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5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053
	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
5054
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072
	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,
5073
			u32 perms)
L
Linus Torvalds 已提交
5074 5075
{
	struct ipc_security_struct *isec;
5076
	struct common_audit_data ad;
5077
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5078 5079 5080

	isec = ipc_perms->security;

5081
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5082 5083
	ad.u.ipc_id = ipc_perms->key;

5084
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100
}

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;
5101
	struct common_audit_data ad;
5102
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5103 5104 5105 5106 5107 5108 5109 5110
	int rc;

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

	isec = msq->q_perm.security;

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

5114
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130
			  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;
5131
	struct common_audit_data ad;
5132
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5133 5134 5135

	isec = msq->q_perm.security;

5136
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5137 5138
	ad.u.ipc_id = msq->q_perm.key;

5139
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5140 5141 5142 5143 5144 5145 5146 5147
			    MSGQ__ASSOCIATE, &ad);
}

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

5148
	switch (cmd) {
L
Linus Torvalds 已提交
5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166
	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;
	}

5167
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5168 5169 5170 5171 5172 5173 5174
	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;
5175
	struct common_audit_data ad;
5176
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189
	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
		 */
5190
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5191
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5192 5193 5194 5195
		if (rc)
			return rc;
	}

5196
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5197 5198 5199
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5200
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5201 5202 5203
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5204 5205
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5206 5207
	if (!rc)
		/* Can the message be put in the queue? */
5208 5209
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5210 5211 5212 5213 5214 5215 5216 5217 5218 5219

	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;
5220
	struct common_audit_data ad;
5221
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5222 5223 5224 5225 5226
	int rc;

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

5227
	ad.type = LSM_AUDIT_DATA_IPC;
5228
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5229

5230
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5231 5232
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5233
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5234 5235 5236 5237 5238 5239 5240 5241
				  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;
5242
	struct common_audit_data ad;
5243
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5244 5245 5246 5247 5248 5249 5250 5251
	int rc;

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

	isec = shp->shm_perm.security;

5252
	ad.type = LSM_AUDIT_DATA_IPC;
5253
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5254

5255
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271
			  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;
5272
	struct common_audit_data ad;
5273
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5274 5275 5276

	isec = shp->shm_perm.security;

5277
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5278 5279
	ad.u.ipc_id = shp->shm_perm.key;

5280
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5281 5282 5283 5284 5285 5286 5287 5288 5289
			    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;

5290
	switch (cmd) {
L
Linus Torvalds 已提交
5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312
	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;
	}

5313
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326
	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;

5327
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5328 5329 5330 5331 5332 5333
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5334
	struct common_audit_data ad;
5335
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5336 5337 5338 5339 5340 5341 5342 5343
	int rc;

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

	isec = sma->sem_perm.security;

5344
	ad.type = LSM_AUDIT_DATA_IPC;
5345
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5346

5347
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363
			  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;
5364
	struct common_audit_data ad;
5365
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5366 5367 5368

	isec = sma->sem_perm.security;

5369
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5370 5371
	ad.u.ipc_id = sma->sem_perm.key;

5372
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5373 5374 5375 5376 5377 5378 5379 5380 5381
			    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;

5382
	switch (cmd) {
L
Linus Torvalds 已提交
5383 5384 5385 5386 5387 5388 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
	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;
	}

5414
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427
	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;

5428
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443
}

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;

5444
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5445 5446
}

5447 5448 5449 5450 5451 5452
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5453
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5454 5455 5456 5457 5458 5459
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5460
			       char *name, char **value)
L
Linus Torvalds 已提交
5461
{
5462
	const struct task_security_struct *__tsec;
5463
	u32 sid;
L
Linus Torvalds 已提交
5464
	int error;
5465
	unsigned len;
L
Linus Torvalds 已提交
5466 5467

	if (current != p) {
5468
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5469 5470 5471 5472
		if (error)
			return error;
	}

5473 5474
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5475 5476

	if (!strcmp(name, "current"))
5477
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5478
	else if (!strcmp(name, "prev"))
5479
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5480
	else if (!strcmp(name, "exec"))
5481
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5482
	else if (!strcmp(name, "fscreate"))
5483
		sid = __tsec->create_sid;
5484
	else if (!strcmp(name, "keycreate"))
5485
		sid = __tsec->keycreate_sid;
5486
	else if (!strcmp(name, "sockcreate"))
5487
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5488
	else
5489 5490
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5491 5492 5493 5494

	if (!sid)
		return 0;

5495 5496 5497 5498
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5499 5500 5501 5502

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5503 5504 5505 5506 5507 5508
}

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
5509
	struct task_struct *tracer;
D
David Howells 已提交
5510 5511
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526
	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"))
5527
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5528
	else if (!strcmp(name, "fscreate"))
5529
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5530
	else if (!strcmp(name, "keycreate"))
5531
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5532
	else if (!strcmp(name, "sockcreate"))
5533
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5534
	else if (!strcmp(name, "current"))
5535
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546
	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--;
		}
5547
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5548
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563
			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);

5564
				return error;
5565
			}
5566 5567 5568
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5569 5570 5571 5572
		if (error)
			return error;
	}

D
David Howells 已提交
5573 5574 5575 5576
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5577 5578 5579
	/* 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
5580
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5581 5582
	   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
5583 5584
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5585
		tsec->exec_sid = sid;
D
David Howells 已提交
5586
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5587
		tsec->create_sid = sid;
D
David Howells 已提交
5588
	} else if (!strcmp(name, "keycreate")) {
5589 5590
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5591
			goto abort_change;
5592
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5593
	} else if (!strcmp(name, "sockcreate")) {
5594
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5595 5596
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5597
		if (sid == 0)
D
David Howells 已提交
5598 5599 5600 5601
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5602
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5603 5604 5605
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5606
		}
L
Linus Torvalds 已提交
5607 5608 5609

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5610
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5611
		if (error)
D
David Howells 已提交
5612
			goto abort_change;
L
Linus Torvalds 已提交
5613 5614 5615

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5616
		ptsid = 0;
5617
		rcu_read_lock();
5618
		tracer = ptrace_parent(p);
D
David Howells 已提交
5619 5620
		if (tracer)
			ptsid = task_sid(tracer);
5621
		rcu_read_unlock();
D
David Howells 已提交
5622 5623 5624 5625

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5626
			if (error)
D
David Howells 已提交
5627
				goto abort_change;
L
Linus Torvalds 已提交
5628 5629
		}

D
David Howells 已提交
5630 5631 5632 5633 5634 5635 5636
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5637
	return size;
D
David Howells 已提交
5638 5639 5640 5641

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5642 5643
}

5644 5645 5646 5647 5648
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5649 5650 5651 5652 5653
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5654
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5655
{
5656
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5657 5658
}

5659 5660
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5661
	kfree(secdata);
5662 5663
}

5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689
/*
 *	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;
}
5690 5691
#ifdef CONFIG_KEYS

D
David Howells 已提交
5692
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5693
			     unsigned long flags)
5694
{
D
David Howells 已提交
5695
	const struct task_security_struct *tsec;
5696 5697 5698 5699 5700 5701
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5702 5703 5704
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5705
	else
D
David Howells 已提交
5706
		ksec->sid = tsec->sid;
5707

5708
	k->security = ksec;
5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720
	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
5721 5722
				  const struct cred *cred,
				  key_perm_t perm)
5723 5724 5725
{
	struct key *key;
	struct key_security_struct *ksec;
5726
	u32 sid;
5727 5728 5729 5730 5731 5732 5733

	/* 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
5734
	sid = cred_sid(cred);
5735 5736 5737 5738 5739

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5740 5741
}

5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755
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;
}

5756 5757
#endif

L
Linus Torvalds 已提交
5758
static struct security_operations selinux_ops = {
5759 5760
	.name =				"selinux",

5761
	.ptrace_access_check =		selinux_ptrace_access_check,
5762
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5763
	.capget =			selinux_capget,
D
David Howells 已提交
5764
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5765 5766 5767 5768 5769 5770 5771 5772
	.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,

5773 5774 5775
	.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
5776 5777 5778 5779 5780
	.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,
5781
	.sb_remount =			selinux_sb_remount,
5782
	.sb_kern_mount =		selinux_sb_kern_mount,
5783
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5784 5785 5786
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5787
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5788
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5789 5790
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5791
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5792 5793 5794

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5795
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813
	.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,
5814 5815 5816
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5817
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5818 5819 5820 5821 5822

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5823 5824
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5825 5826 5827 5828 5829 5830 5831
	.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,

5832
	.file_open =			selinux_file_open,
5833

L
Linus Torvalds 已提交
5834
	.task_create =			selinux_task_create,
5835
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5836
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5837
	.cred_prepare =			selinux_cred_prepare,
5838
	.cred_transfer =		selinux_cred_transfer,
5839 5840
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5841
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5842 5843
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5844
	.task_getsid =			selinux_task_getsid,
5845
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5846
	.task_setnice =			selinux_task_setnice,
5847
	.task_setioprio =		selinux_task_setioprio,
5848
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5849 5850 5851
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5852
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5853 5854
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5855
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5856 5857

	.ipc_permission =		selinux_ipc_permission,
5858
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875

	.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,

5876 5877
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5878 5879 5880 5881
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5882
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5883

5884 5885
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5886

5887
	.ismaclabel =			selinux_ismaclabel,
5888
	.secid_to_secctx =		selinux_secid_to_secctx,
5889
	.secctx_to_secid =		selinux_secctx_to_secid,
5890
	.release_secctx =		selinux_release_secctx,
5891 5892 5893
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5894

5895
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5896 5897 5898 5899 5900 5901 5902 5903 5904 5905 5906 5907 5908 5909 5910 5911
	.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
5912 5913
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5914 5915
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5916
	.sk_clone_security =		selinux_sk_clone_security,
5917
	.sk_getsecid =			selinux_sk_getsecid,
5918 5919 5920
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5921
	.inet_conn_established =	selinux_inet_conn_established,
5922 5923 5924
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5925
	.req_classify_flow =		selinux_req_classify_flow,
5926 5927
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5928
	.tun_dev_create =		selinux_tun_dev_create,
5929
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5930
	.tun_dev_attach =		selinux_tun_dev_attach,
5931
	.tun_dev_open =			selinux_tun_dev_open,
5932
	.skb_owned_by =			selinux_skb_owned_by,
5933 5934 5935 5936 5937

#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
5938
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5939 5940
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5941
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5942
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5943
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5944 5945
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5946
#endif
5947 5948

#ifdef CONFIG_KEYS
5949 5950 5951
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5952
	.key_getsecurity =		selinux_key_getsecurity,
5953
#endif
5954 5955 5956 5957 5958 5959 5960

#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
5961 5962 5963 5964
};

static __init int selinux_init(void)
{
5965 5966 5967 5968 5969
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5970 5971 5972 5973 5974 5975 5976 5977
	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
5978
	cred_init_security();
L
Linus Torvalds 已提交
5979

5980 5981
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5982 5983
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5984
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5985 5986
	avc_init();

5987
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5988 5989
		panic("SELinux: Unable to register with kernel.\n");

5990
	if (selinux_enforcing)
5991
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5992
	else
5993
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5994

L
Linus Torvalds 已提交
5995 5996 5997
	return 0;
}

5998 5999 6000 6001 6002
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
6003 6004
void selinux_complete_init(void)
{
6005
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
6006 6007

	/* Set up any superblocks initialized prior to the policy load. */
6008
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6009
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
6010 6011 6012 6013 6014 6015
}

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

6016
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
6017

6018 6019 6020 6021
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
6022
		.pf =		NFPROTO_IPV4,
6023 6024 6025 6026 6027 6028
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
6029
		.pf =		NFPROTO_IPV4,
6030 6031
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6032 6033 6034 6035
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6036
		.pf =		NFPROTO_IPV4,
6037 6038
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6039
	}
L
Linus Torvalds 已提交
6040 6041 6042 6043
};

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

6044 6045 6046 6047
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6048
		.pf =		NFPROTO_IPV6,
6049 6050 6051 6052 6053 6054
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6055
		.pf =		NFPROTO_IPV6,
6056 6057 6058
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
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6059 6060 6061 6062 6063 6064 6065 6066 6067 6068
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
6069 6070 6071

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

6072 6073 6074
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
6075 6076

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6077 6078 6079
	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
6080
#endif	/* IPV6 */
6081

L
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6082 6083 6084 6085 6086 6087 6088 6089 6090
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6091
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6092

6093
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
6094
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6095
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
6096 6097 6098 6099
#endif	/* IPV6 */
}
#endif

6100
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6101 6102 6103 6104 6105

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6106
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6107 6108

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6109 6110
static int selinux_disabled;

L
Linus Torvalds 已提交
6111 6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124 6125
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;
6126
	selinux_enabled = 0;
L
Linus Torvalds 已提交
6127

6128
	reset_security_ops();
L
Linus Torvalds 已提交
6129

6130 6131 6132
	/* Try to destroy the avc node cache */
	avc_disable();

L
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6133 6134 6135 6136 6137 6138 6139 6140 6141
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif