hooks.c 149.7 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/sock.h>
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#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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#include <net/inet_connection_sock.h>
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#include <net/net_namespace.h>
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#include <net/netlabel.h>
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
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#include <net/netlink.h>
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#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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extern struct security_operations *security_ops;
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/* SECMARK reference count */
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static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
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#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
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int selinux_enforcing;
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static int __init enforcing_setup(char *str)
{
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	unsigned long enforcing;
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	if (!kstrtoul(str, 0, &enforcing))
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		selinux_enforcing = enforcing ? 1 : 0;
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	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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static const char *labeling_behaviors[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;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
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	}
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	if (sbsec->flags & SBLABEL_MNT) {
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		opts->mnt_opts[i] = NULL;
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		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
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	}
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	BUG_ON(i != opts->num_mnt_opts);
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	return 0;

out_free:
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	security_free_mnt_opts(opts);
564 565
	return rc;
}
L
Linus Torvalds 已提交
566

567 568 569
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
570 571
	char mnt_flags = sbsec->flags & SE_MNTMASK;

572
	/* check if the old mount command had the same options */
573
	if (sbsec->flags & SE_SBINITIALIZED)
574 575 576 577 578 579 580
		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
	 */
581 582
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
583 584 585
			return 1;
	return 0;
}
586

587 588 589 590
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
591
static int selinux_set_mnt_opts(struct super_block *sb,
592 593 594
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
595
{
596
	const struct cred *cred = current_cred();
597 598
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
599
	const char *name = sb->s_type->name;
600 601
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
602 603
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
604 605 606
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
607 608 609 610 611 612 613 614 615 616 617

	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
618 619
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
620
		goto out;
621
	}
622 623 624 625 626 627
	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
628

629 630 631 632 633 634 635 636 637 638 639
	/*
	 * 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)
	 */
640
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
641
	    && (num_opts == 0))
642
		goto out;
643

644 645 646 647 648 649 650
	/*
	 * 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;
651

652
		if (flags[i] == SBLABEL_MNT)
653
			continue;
654 655
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
656 657
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
658 659
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703
			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
704
		}
705 706
	}

707
	if (sbsec->flags & SE_SBINITIALIZED) {
708
		/* previously mounted with options, but not on this attempt? */
709
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
710 711 712 713 714
			goto out_double_mount;
		rc = 0;
		goto out;
	}

715
	if (strcmp(sb->s_type->name, "proc") == 0)
716
		sbsec->flags |= SE_SBPROC;
717

718 719 720 721 722
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
723
		rc = security_fs_use(sb);
724 725 726 727 728 729
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
730 731 732
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
733
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
734
		if (rc)
735
			goto out;
L
Linus Torvalds 已提交
736

737
		sbsec->sid = fscontext_sid;
738 739 740 741 742 743 744
	}

	/*
	 * 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.
	 */
745 746 747 748 749
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

750 751
	if (context_sid) {
		if (!fscontext_sid) {
752 753
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
754
			if (rc)
755 756
				goto out;
			sbsec->sid = context_sid;
757
		} else {
758 759
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
760
			if (rc)
761
				goto out;
762
		}
763 764
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
765

766
		sbsec->mntpoint_sid = context_sid;
767
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
768 769
	}

770
	if (rootcontext_sid) {
771 772
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
773
		if (rc)
774
			goto out;
775

776 777
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
778 779
	}

780
	if (defcontext_sid) {
781 782
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
783 784 785 786
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
787 788
		}

789 790
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
791
							     sbsec, cred);
792 793 794
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
795

796
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
797 798
	}

799
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
800
out:
801
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
802
	return rc;
803 804 805
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
806
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
807
	goto out;
L
Linus Torvalds 已提交
808 809
}

810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
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,
841
					struct super_block *newsb)
L
Linus Torvalds 已提交
842
{
843 844
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
845

846 847 848
	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
849

850 851
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
852
	 * mount options.  thus we can safely deal with this superblock later
853
	 */
854
	if (!ss_initialized)
855
		return 0;
856 857

	/* how can we clone if the old one wasn't set up?? */
858
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
859

860
	/* if fs is reusing a sb, make sure that the contexts match */
861
	if (newsbsec->flags & SE_SBINITIALIZED)
862
		return selinux_cmp_sb_context(oldsb, newsb);
863

864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882
	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
883
	}
884 885 886 887 888
	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
889

890
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
891 892
	}

893 894
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
895
	return 0;
896 897
}

898 899
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
900
{
901
	char *p;
902 903
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
904
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
905

906
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
907

908 909 910 911
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
912

913 914
		if (!*p)
			continue;
L
Linus Torvalds 已提交
915

916
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
917

918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
		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;
970 971
		case Opt_labelsupport:
			break;
972 973 974 975
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
976 977 978

		}
	}
979

980 981 982 983 984 985 986 987 988 989 990
	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;
	}

991
	if (fscontext) {
992 993
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
994 995
	}
	if (context) {
996 997
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
998 999
	}
	if (rootcontext) {
1000 1001
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1002 1003
	}
	if (defcontext) {
1004 1005
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1006 1007
	}

1008 1009 1010
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1011 1012 1013 1014 1015
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1016 1017
	return rc;
}
1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
/*
 * 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:
1039
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1040 1041 1042 1043 1044

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1045

A
Adrian Bunk 已提交
1046 1047
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1048 1049 1050 1051 1052
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1053 1054 1055 1056 1057 1058
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072

		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;
1073
		case SBLABEL_MNT:
1074 1075 1076
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1077 1078
		default:
			BUG();
1079
			return;
1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
		};
		/* 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);
1098 1099 1100 1101
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1102
		return rc;
1103
	}
1104 1105 1106 1107 1108 1109 1110 1111

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134
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;
}

1135 1136 1137 1138 1139 1140 1141 1142 1143 1144
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
1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160
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:
1161 1162 1163 1164
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1165
		case SOCK_DGRAM:
1166 1167 1168 1169
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1170 1171
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1172
		default:
L
Linus Torvalds 已提交
1173 1174 1175 1176 1177 1178 1179 1180 1181
			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;
1182
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
			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;
1196 1197
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1198 1199 1200 1201 1202 1203 1204
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1205 1206
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1207 1208 1209 1210 1211 1212
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1213
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1214 1215 1216
				u16 tclass,
				u32 *sid)
{
1217 1218
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1219

1220
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1221 1222 1223
	if (!buffer)
		return -ENOMEM;

1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235
	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
1236 1237 1238 1239 1240
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1241
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
				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;

1264
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1265
	if (isec->initialized)
1266
		goto out_unlock;
L
Linus Torvalds 已提交
1267 1268

	sbsec = inode->i_sb->s_security;
1269
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1270 1271 1272 1273 1274 1275 1276
		/* 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);
1277
		goto out_unlock;
L
Linus Torvalds 已提交
1278 1279 1280
	}

	switch (sbsec->behavior) {
1281 1282
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298
	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) {
1299 1300 1301 1302 1303 1304 1305 1306 1307
			/*
			 * 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.
			 */
1308
			goto out_unlock;
L
Linus Torvalds 已提交
1309 1310 1311
		}

		len = INITCONTEXTLEN;
1312
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1313 1314 1315
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1316
			goto out_unlock;
L
Linus Torvalds 已提交
1317
		}
1318
		context[len] = '\0';
L
Linus Torvalds 已提交
1319 1320 1321
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1322 1323
			kfree(context);

L
Linus Torvalds 已提交
1324 1325 1326 1327 1328
			/* 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);
1329
				goto out_unlock;
L
Linus Torvalds 已提交
1330 1331
			}
			len = rc;
1332
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1333 1334 1335
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1336
				goto out_unlock;
L
Linus Torvalds 已提交
1337
			}
1338
			context[len] = '\0';
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345
			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
1346
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1347
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1348 1349
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1350
				goto out_unlock;
L
Linus Torvalds 已提交
1351 1352 1353 1354 1355
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1356
			rc = security_context_to_sid_default(context, rc, &sid,
1357 1358
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1359
			if (rc) {
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390
				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);
1391 1392
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1393
		if (rc)
1394
			goto out_unlock;
L
Linus Torvalds 已提交
1395 1396
		isec->sid = sid;
		break;
1397 1398 1399
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1400
	default:
1401
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1402 1403
		isec->sid = sbsec->sid;

1404
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1405
			if (opt_dentry) {
L
Linus Torvalds 已提交
1406
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1407
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1408 1409 1410
							  isec->sclass,
							  &sid);
				if (rc)
1411
					goto out_unlock;
L
Linus Torvalds 已提交
1412 1413 1414 1415 1416 1417 1418 1419
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1420 1421
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
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 1448 1449 1450 1451 1452 1453 1454
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
1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467
/*
 * 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);
}

1468
/*
1469
 * Check permission between a pair of tasks, e.g. signal checks,
1470 1471
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1472
 * - this uses the default subjective creds of tsk1
1473 1474 1475
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1476 1477
			 u32 perms)
{
1478 1479
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1480

1481 1482 1483 1484 1485
	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
1486 1487
}

1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503
/*
 * 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);
}

1504 1505 1506 1507
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1508
/* Check whether a task is allowed to use a capability. */
1509
static int cred_has_capability(const struct cred *cred,
1510
			       int cap, int audit)
L
Linus Torvalds 已提交
1511
{
1512
	struct common_audit_data ad;
1513
	struct av_decision avd;
1514
	u16 sclass;
1515
	u32 sid = cred_sid(cred);
1516
	u32 av = CAP_TO_MASK(cap);
1517
	int rc;
L
Linus Torvalds 已提交
1518

1519
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1520 1521
	ad.u.cap = cap;

1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532
	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();
1533
		return -EINVAL;
1534
	}
1535

1536
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1537
	if (audit == SECURITY_CAP_AUDIT) {
1538
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1539 1540 1541
		if (rc2)
			return rc2;
	}
1542
	return rc;
L
Linus Torvalds 已提交
1543 1544 1545 1546 1547 1548
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1549
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1550

1551
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1552 1553 1554 1555 1556 1557
			    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). */
1558
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1559 1560
			  struct inode *inode,
			  u32 perms,
1561
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1562 1563
{
	struct inode_security_struct *isec;
1564
	u32 sid;
L
Linus Torvalds 已提交
1565

1566 1567
	validate_creds(cred);

1568
	if (unlikely(IS_PRIVATE(inode)))
1569 1570
		return 0;

1571
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1572 1573
	isec = inode->i_security;

1574
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1575 1576 1577 1578 1579
}

/* 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. */
1580
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1581 1582 1583 1584
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1585
	struct common_audit_data ad;
1586

1587
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1588
	ad.u.dentry = dentry;
1589
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601
}

/* 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;

1602
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1603
	ad.u.path = *path;
1604
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1605 1606
}

1607 1608 1609 1610 1611 1612 1613 1614 1615
/* 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;
1616
	return inode_has_perm(cred, file_inode(file), av, &ad);
1617 1618
}

L
Linus Torvalds 已提交
1619 1620 1621 1622 1623 1624 1625 1626
/* 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. */
1627 1628 1629
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1630 1631
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1632
	struct inode *inode = file_inode(file);
1633
	struct common_audit_data ad;
1634
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1635 1636
	int rc;

1637
	ad.type = LSM_AUDIT_DATA_PATH;
1638
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1639

1640 1641
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1642 1643 1644 1645
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1646
			goto out;
L
Linus Torvalds 已提交
1647 1648 1649
	}

	/* av is zero if only checking access to the descriptor. */
1650
	rc = 0;
L
Linus Torvalds 已提交
1651
	if (av)
1652
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1653

1654 1655
out:
	return rc;
L
Linus Torvalds 已提交
1656 1657 1658 1659 1660 1661 1662
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1663
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1664 1665
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1666
	u32 sid, newsid;
1667
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1668 1669 1670 1671 1672
	int rc;

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

1673 1674 1675
	sid = tsec->sid;
	newsid = tsec->create_sid;

1676
	ad.type = LSM_AUDIT_DATA_DENTRY;
1677
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1678

1679
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1680 1681 1682 1683 1684
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1685
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1686 1687
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1688 1689 1690 1691
		if (rc)
			return rc;
	}

1692
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1693 1694 1695 1696 1697 1698 1699 1700
	if (rc)
		return rc;

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

1701 1702 1703 1704
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1705
	u32 sid = task_sid(ctx);
1706

1707
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1708 1709
}

1710 1711 1712
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1713 1714 1715 1716 1717 1718 1719 1720

/* 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;
1721
	struct common_audit_data ad;
1722
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1723 1724 1725 1726 1727 1728
	u32 av;
	int rc;

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

1729
	ad.type = LSM_AUDIT_DATA_DENTRY;
1730
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1731 1732 1733

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1734
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748
	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
1749 1750
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1751 1752 1753
		return 0;
	}

1754
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1755 1756 1757 1758 1759 1760 1761 1762 1763
	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;
1764
	struct common_audit_data ad;
1765
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1766 1767 1768 1769 1770 1771 1772 1773 1774
	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;

1775
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1776

1777
	ad.u.dentry = old_dentry;
1778
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1779 1780 1781
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1782
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1783 1784 1785 1786
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1787
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1788 1789 1790 1791 1792
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1793
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1794 1795 1796
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1797
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1798 1799 1800 1801 1802
	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);
1803
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1804 1805 1806 1807 1808 1809 1810 1811 1812 1813
				  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. */
1814
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1815 1816
			       struct super_block *sb,
			       u32 perms,
1817
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1818 1819
{
	struct superblock_security_struct *sbsec;
1820
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1821 1822

	sbsec = sb->s_security;
1823
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1824 1825 1826 1827 1828 1829 1830
}

/* 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
1831
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853
		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;
}

1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876
/* 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
1877
/*
1878
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1879 1880
 * open permission.
 */
1881
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1882
{
1883
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1884

1885 1886 1887
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1888 1889 1890
	return av;
}

L
Linus Torvalds 已提交
1891 1892
/* Hook functions begin here. */

1893
static int selinux_ptrace_access_check(struct task_struct *child,
1894
				     unsigned int mode)
L
Linus Torvalds 已提交
1895 1896 1897
{
	int rc;

1898
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1899 1900 1901
	if (rc)
		return rc;

1902
	if (mode & PTRACE_MODE_READ) {
1903 1904 1905
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1906 1907
	}

1908
	return current_has_perm(child, PROCESS__PTRACE);
1909 1910 1911 1912 1913 1914
}

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

1915
	rc = cap_ptrace_traceme(parent);
1916 1917 1918 1919
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1920 1921 1922
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1923
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1924 1925 1926
{
	int error;

1927
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1928 1929 1930
	if (error)
		return error;

1931
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1932 1933
}

D
David Howells 已提交
1934 1935 1936 1937
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
1938 1939 1940
{
	int error;

1941
	error = cap_capset(new, old,
D
David Howells 已提交
1942
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1943 1944 1945
	if (error)
		return error;

D
David Howells 已提交
1946
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1947 1948
}

1949 1950 1951 1952 1953 1954 1955 1956 1957 1958
/*
 * (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.
 */

1959 1960
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1961 1962 1963
{
	int rc;

1964
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1965 1966 1967
	if (rc)
		return rc;

1968
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1969 1970 1971 1972
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1973
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1974 1975 1976 1977 1978 1979
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1980 1981 1982 1983 1984
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1985
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1986 1987 1988 1989
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1990
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1991 1992 1993 1994
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1995 1996 1997 1998 1999 2000
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2001 2002
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2003
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2004 2005
}

2006
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2007 2008 2009 2010
{
	int rc;

	switch (type) {
2011 2012
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2013 2014
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2015 2016 2017 2018
	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:
2019 2020
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2021 2022 2023 2024 2025
	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 */
2026 2027 2028
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
	}
	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.
 */
2041
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2042 2043 2044
{
	int rc, cap_sys_admin = 0;

2045
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2046
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2047 2048 2049
	if (rc == 0)
		cap_sys_admin = 1;

2050
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2051 2052 2053 2054
}

/* binprm security operations */

2055
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2056
{
2057 2058
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2059
	struct inode_security_struct *isec;
2060
	struct common_audit_data ad;
A
Al Viro 已提交
2061
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2062 2063
	int rc;

2064
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2065 2066 2067
	if (rc)
		return rc;

2068 2069 2070
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2071 2072
		return 0;

2073 2074
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2075 2076 2077
	isec = inode->i_security;

	/* Default to the current task SID. */
2078 2079
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2080

2081
	/* Reset fs, key, and sock SIDs on execve. */
2082 2083 2084
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2085

2086 2087
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2088
		/* Reset exec SID on execve. */
2089
		new_tsec->exec_sid = 0;
2090 2091 2092 2093 2094 2095 2096

		/*
		 * 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
2097 2098
	} else {
		/* Check for a default transition on this program. */
2099
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2100 2101
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2102 2103 2104 2105
		if (rc)
			return rc;
	}

2106
	ad.type = LSM_AUDIT_DATA_PATH;
2107
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2108

2109 2110
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2111
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2112

2113 2114
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2115 2116 2117 2118 2119
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2120
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2121 2122 2123 2124
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2125
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2126 2127 2128 2129
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147
		/* 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();
2148
			tracer = ptrace_parent(current);
2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
			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
2163

2164 2165
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2166 2167 2168 2169 2170
	}

	return 0;
}

2171
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2172
{
2173
	const struct task_security_struct *tsec = current_security();
2174
	u32 sid, osid;
L
Linus Torvalds 已提交
2175 2176
	int atsecure = 0;

2177 2178 2179 2180
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2181 2182 2183
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2184
		atsecure = avc_has_perm(osid, sid,
2185 2186
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2187 2188
	}

2189
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2190 2191
}

A
Al Viro 已提交
2192 2193 2194 2195 2196
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
2197
/* Derived from fs/exec.c:flush_old_files. */
2198 2199
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2200 2201
{
	struct file *file, *devnull = NULL;
2202
	struct tty_struct *tty;
2203
	int drop_tty = 0;
A
Al Viro 已提交
2204
	unsigned n;
L
Linus Torvalds 已提交
2205

2206
	tty = get_current_tty();
L
Linus Torvalds 已提交
2207
	if (tty) {
N
Nick Piggin 已提交
2208
		spin_lock(&tty_files_lock);
2209
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2210
			struct tty_file_private *file_priv;
2211

L
Linus Torvalds 已提交
2212
			/* Revalidate access to controlling tty.
2213 2214 2215 2216
			   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
2217 2218 2219
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2220
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2221
				drop_tty = 1;
L
Linus Torvalds 已提交
2222
		}
N
Nick Piggin 已提交
2223
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2224
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2225
	}
2226 2227 2228
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2229 2230

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2231 2232 2233
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2234

A
Al Viro 已提交
2235
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2236 2237 2238 2239 2240 2241 2242
	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
2243
		fput(devnull);
L
Linus Torvalds 已提交
2244 2245
}

2246 2247 2248 2249
/*
 * 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
2250
{
2251 2252 2253
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2254

2255 2256 2257
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2258

2259 2260
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2261

2262 2263
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2264

2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277
	/* 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) {
2278 2279
		/* protect against do_prlimit() */
		task_lock(current);
2280 2281 2282 2283
		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
2284
		}
2285 2286
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2287 2288 2289 2290
	}
}

/*
2291 2292
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2293
 */
2294
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2295
{
2296
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2297
	struct itimerval itimer;
2298
	u32 osid, sid;
L
Linus Torvalds 已提交
2299 2300
	int rc, i;

2301 2302 2303 2304
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2305 2306
		return;

2307 2308 2309 2310 2311 2312 2313 2314
	/* 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
2315 2316 2317 2318 2319
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2320 2321 2322 2323 2324
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2325 2326 2327
		spin_unlock_irq(&current->sighand->siglock);
	}

2328 2329
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2330
	read_lock(&tasklist_lock);
2331
	__wake_up_parent(current, current->real_parent);
2332
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356
}

/* 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)
{
2357 2358 2359
	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) ||
2360 2361
		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
2362 2363 2364 2365 2366 2367 2368
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2369
	} else
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2375 2376
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2377 2378 2379 2380 2381 2382
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2383
	} else
2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395
		*first = 0;

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

2396
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2397 2398 2399 2400
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2401
	int open_quote = 0;
L
Linus Torvalds 已提交
2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416

	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 {
2417 2418 2419 2420
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2421 2422 2423
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2424
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2425 2426 2427 2428 2429 2430 2431
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2432
	strcpy(in_save, nosec_save);
2433
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2434 2435 2436 2437
out:
	return rc;
}

2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472
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;

2473
		if (flags[i] == SBLABEL_MNT)
2474 2475 2476 2477 2478
			continue;
		len = strlen(mount_options[i]);
		rc = security_context_to_sid(mount_options[i], len, &sid);
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2479 2480
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517
			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 "
2518 2519
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2520 2521 2522
	goto out_free_opts;
}

2523
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2524
{
2525
	const struct cred *cred = current_cred();
2526
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2527 2528 2529 2530 2531 2532
	int rc;

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

2533 2534 2535 2536
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2537
	ad.type = LSM_AUDIT_DATA_DENTRY;
2538
	ad.u.dentry = sb->s_root;
2539
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2540 2541
}

2542
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2543
{
2544
	const struct cred *cred = current_cred();
2545
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2546

2547
	ad.type = LSM_AUDIT_DATA_DENTRY;
2548
	ad.u.dentry = dentry->d_sb->s_root;
2549
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2550 2551
}

A
Al Viro 已提交
2552
static int selinux_mount(const char *dev_name,
2553
			 struct path *path,
A
Al Viro 已提交
2554
			 const char *type,
2555 2556
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2557
{
2558
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2559 2560

	if (flags & MS_REMOUNT)
2561
		return superblock_has_perm(cred, path->dentry->d_sb,
2562
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2563
	else
E
Eric Paris 已提交
2564
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2565 2566 2567 2568
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2569
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2570

2571
	return superblock_has_perm(cred, mnt->mnt_sb,
2572
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586
}

/* 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);
}

2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620
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);
}

2621
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2622 2623
				       const struct qstr *qstr,
				       const char **name,
2624
				       void **value, size_t *len)
2625
{
2626
	const struct task_security_struct *tsec = current_security();
2627 2628
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2629
	u32 sid, newsid, clen;
2630
	int rc;
2631
	char *context;
2632 2633 2634 2635

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

2636 2637 2638
	sid = tsec->sid;
	newsid = tsec->create_sid;

2639 2640 2641
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2642
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2643
		rc = security_transition_sid(sid, dsec->sid,
2644
					     inode_mode_to_security_class(inode->i_mode),
2645
					     qstr, &newsid);
2646 2647 2648 2649
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2650
			       __func__,
2651 2652 2653 2654 2655
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2656
	/* Possibly defer initialization to selinux_complete_init. */
2657
	if (sbsec->flags & SE_SBINITIALIZED) {
2658 2659 2660 2661 2662
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2663

2664
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2665 2666
		return -EOPNOTSUPP;

2667 2668
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2669

2670
	if (value && len) {
2671
		rc = security_sid_to_context_force(newsid, &context, &clen);
2672
		if (rc)
2673 2674 2675
			return rc;
		*value = context;
		*len = clen;
2676 2677 2678 2679 2680
	}

	return 0;
}

A
Al Viro 已提交
2681
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700
{
	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);
}

2701
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2702 2703 2704 2705 2706 2707 2708 2709 2710
{
	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
2711
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2712 2713 2714 2715 2716
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2717
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2718 2719 2720 2721 2722 2723
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2724 2725
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2726
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2727 2728 2729 2730
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2731
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2732

E
Eric Paris 已提交
2733
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2734 2735
}

2736 2737 2738
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2739
{
2740
	struct common_audit_data ad;
2741 2742 2743
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2744
	ad.type = LSM_AUDIT_DATA_INODE;
2745 2746 2747 2748 2749 2750 2751 2752 2753
	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;
}

2754
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2755
{
2756
	const struct cred *cred = current_cred();
2757 2758
	u32 perms;
	bool from_access;
2759
	unsigned flags = mask & MAY_NOT_BLOCK;
2760 2761 2762 2763 2764
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2765

2766
	from_access = mask & MAY_ACCESS;
2767 2768
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2769 2770
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2771 2772
		return 0;

2773
	validate_creds(cred);
2774

2775 2776
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2777 2778 2779

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

2780 2781 2782 2783 2784 2785 2786 2787 2788 2789
	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;

2790
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2791 2792 2793
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2794 2795 2796 2797
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2798
	const struct cred *cred = current_cred();
2799
	unsigned int ia_valid = iattr->ia_valid;
2800
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2801

2802 2803 2804 2805 2806 2807 2808
	/* 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
2809

2810 2811
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2812
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2813

2814
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2815 2816 2817
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2818 2819 2820 2821
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2822
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2823 2824 2825 2826
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2827

E
Eric Paris 已提交
2828
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2829 2830
}

2831
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2832
{
2833 2834
	const struct cred *cred = current_cred();

2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848
	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
2849
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2850 2851
}

2852 2853
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
2854 2855 2856 2857
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2858
	struct common_audit_data ad;
2859
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2860 2861
	int rc = 0;

2862 2863
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2864 2865

	sbsec = inode->i_sb->s_security;
2866
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2867 2868
		return -EOPNOTSUPP;

2869
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2870 2871
		return -EPERM;

2872
	ad.type = LSM_AUDIT_DATA_DENTRY;
2873
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2874

2875
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2876 2877 2878 2879 2880
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2881
	if (rc == -EINVAL) {
2882 2883 2884 2885 2886 2887 2888
		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 */
2889 2890 2891 2892 2893 2894 2895 2896 2897 2898
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2899 2900 2901 2902 2903
			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);

2904
			return rc;
2905
		}
2906 2907
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2908 2909 2910
	if (rc)
		return rc;

2911
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2912 2913 2914 2915
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2916
	rc = security_validate_transition(isec->sid, newsid, sid,
2917
					  isec->sclass);
L
Linus Torvalds 已提交
2918 2919 2920 2921 2922 2923 2924 2925 2926 2927
	if (rc)
		return rc;

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

2928
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2929
					const void *value, size_t size,
2930
					int flags)
L
Linus Torvalds 已提交
2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941
{
	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;
	}

2942
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2943
	if (rc) {
2944 2945 2946
		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
2947 2948 2949
		return;
	}

2950
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
2951
	isec->sid = newsid;
2952 2953
	isec->initialized = 1;

L
Linus Torvalds 已提交
2954 2955 2956
	return;
}

2957
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2958
{
2959 2960
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2961
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2962 2963
}

2964
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2965
{
2966 2967
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2968
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2969 2970
}

2971
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2972
{
2973 2974
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2975 2976 2977 2978 2979 2980

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

2981
/*
2982
 * Copy the inode security context value to the user.
2983 2984 2985
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2986
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2987
{
2988 2989 2990
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2991
	struct inode_security_struct *isec = inode->i_security;
2992

2993 2994
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2995

2996 2997 2998 2999 3000 3001 3002 3003 3004
	/*
	 * 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.
	 */
3005
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3006
				SECURITY_CAP_NOAUDIT);
3007 3008 3009 3010 3011
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3012 3013 3014 3015 3016 3017 3018 3019 3020 3021
	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
3022 3023 3024
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3025
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036
{
	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;

3037
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
3038 3039 3040
	if (rc)
		return rc;

3041
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3042
	isec->sid = newsid;
3043
	isec->initialized = 1;
L
Linus Torvalds 已提交
3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054
	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;
}

3055 3056 3057 3058 3059 3060
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
3061 3062
/* file security operations */

3063
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3064
{
3065
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3066
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3067 3068 3069 3070 3071

	/* 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;

3072 3073
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3074 3075
}

3076 3077
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3078
	struct inode *inode = file_inode(file);
3079 3080 3081 3082
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3083
	if (!mask)
3084 3085 3086
		/* No permission to check.  Existence test. */
		return 0;

3087 3088
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3089
		/* No change since file_open check. */
3090 3091
		return 0;

3092 3093 3094
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
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)
{
3108
	const struct cred *cred = current_cred();
3109
	int error = 0;
L
Linus Torvalds 已提交
3110

3111 3112 3113 3114 3115 3116 3117
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3118
	case FS_IOC_GETFLAGS:
3119
	/* fall through */
3120
	case FS_IOC_GETVERSION:
3121 3122
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3123

3124
	case FS_IOC_SETFLAGS:
3125
	/* fall through */
3126
	case FS_IOC_SETVERSION:
3127 3128 3129 3130 3131 3132 3133 3134 3135
		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
3136

3137 3138
	case KDSKBENT:
	case KDSKBSENT:
3139 3140
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3141 3142 3143 3144 3145 3146 3147 3148 3149
		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
3150 3151
}

3152 3153
static int default_noexec;

L
Linus Torvalds 已提交
3154 3155
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3156
	const struct cred *cred = current_cred();
D
David Howells 已提交
3157
	int rc = 0;
3158

3159 3160
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3161 3162 3163 3164 3165
		/*
		 * 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
3166
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3167
		if (rc)
D
David Howells 已提交
3168
			goto error;
L
Linus Torvalds 已提交
3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181
	}

	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;

3182
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3183
	}
D
David Howells 已提交
3184 3185 3186

error:
	return rc;
L
Linus Torvalds 已提交
3187 3188
}

3189
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3190
{
3191 3192 3193 3194 3195 3196
	int rc;

	/* do DAC check on address space usage */
	rc = cap_mmap_addr(addr);
	if (rc)
		return rc;
L
Linus Torvalds 已提交
3197

3198
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3199
		u32 sid = current_sid();
3200 3201
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3202 3203
	}

3204
	return rc;
3205
}
L
Linus Torvalds 已提交
3206

3207 3208 3209
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220
	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)
{
3221
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3222 3223 3224 3225

	if (selinux_checkreqprot)
		prot = reqprot;

3226 3227
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3228
		int rc = 0;
3229 3230
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3231
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3232 3233 3234
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3235
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3236 3237 3238 3239 3240 3241 3242 3243
		} 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
3244
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3245
		}
3246 3247 3248
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3249 3250 3251 3252 3253 3254

	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)
{
3255 3256 3257
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3258 3259 3260 3261 3262
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3263
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3264 3265 3266
	int err = 0;

	switch (cmd) {
3267 3268
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3269
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3270
			break;
3271 3272 3273 3274 3275 3276 3277
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3278
	case F_GETOWNER_UIDS:
3279
		/* Just check FD__USE permission */
3280
		err = file_has_perm(cred, file, 0);
3281 3282 3283 3284
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3285
#if BITS_PER_LONG == 32
3286 3287 3288
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3289
#endif
3290
		err = file_has_perm(cred, file, FILE__LOCK);
3291
		break;
L
Linus Torvalds 已提交
3292 3293 3294 3295 3296 3297 3298 3299 3300 3301
	}

	return err;
}

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

	fsec = file->f_security;
3302
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3303 3304 3305 3306 3307 3308 3309

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3310
	struct file *file;
3311
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3312 3313 3314 3315
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3316
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3317 3318 3319 3320 3321 3322 3323 3324

	fsec = file->f_security;

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

3325
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3326 3327 3328 3329 3330
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3331 3332 3333
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3334 3335
}

3336
static int selinux_file_open(struct file *file, const struct cred *cred)
3337 3338 3339
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3340

3341
	fsec = file->f_security;
A
Al Viro 已提交
3342
	isec = file_inode(file)->i_security;
3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359
	/*
	 * 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.
	 */
3360
	return file_path_has_perm(cred, file, open_file_to_av(file));
3361 3362
}

L
Linus Torvalds 已提交
3363 3364 3365 3366
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3367
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3368 3369
}

3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384
/*
 * 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
3385 3386 3387 3388
/*
 * 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
3389
{
D
David Howells 已提交
3390
	struct task_security_struct *tsec = cred->security;
3391

3392 3393 3394 3395 3396
	/*
	 * 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);
3397
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3398 3399
	kfree(tsec);
}
L
Linus Torvalds 已提交
3400

D
David Howells 已提交
3401 3402 3403 3404 3405 3406 3407 3408
/*
 * 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
3409

D
David Howells 已提交
3410
	old_tsec = old->security;
L
Linus Torvalds 已提交
3411

D
David Howells 已提交
3412 3413 3414
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3415

D
David Howells 已提交
3416
	new->security = tsec;
L
Linus Torvalds 已提交
3417 3418 3419
	return 0;
}

3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430
/*
 * 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;
}

3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471
/*
 * 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;
3472
	return ret;
3473 3474
}

3475
static int selinux_kernel_module_request(char *kmod_name)
3476
{
3477 3478 3479 3480 3481
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3482
	ad.type = LSM_AUDIT_DATA_KMOD;
3483 3484 3485 3486
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3487 3488
}

L
Linus Torvalds 已提交
3489 3490
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3491
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3492 3493 3494 3495
}

static int selinux_task_getpgid(struct task_struct *p)
{
3496
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3497 3498 3499 3500
}

static int selinux_task_getsid(struct task_struct *p)
{
3501
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3502 3503
}

3504 3505
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3506
	*secid = task_sid(p);
3507 3508
}

L
Linus Torvalds 已提交
3509 3510 3511 3512
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3513
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3514 3515 3516
	if (rc)
		return rc;

3517
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3518 3519
}

3520 3521
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3522 3523
	int rc;

3524
	rc = cap_task_setioprio(p, ioprio);
3525 3526 3527
	if (rc)
		return rc;

3528
	return current_has_perm(p, PROCESS__SETSCHED);
3529 3530
}

3531 3532
static int selinux_task_getioprio(struct task_struct *p)
{
3533
	return current_has_perm(p, PROCESS__GETSCHED);
3534 3535
}

3536 3537
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3538
{
3539
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3540 3541 3542 3543

	/* 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
3544
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3545
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3546
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3547 3548 3549 3550

	return 0;
}

3551
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3552
{
3553 3554
	int rc;

3555
	rc = cap_task_setscheduler(p);
3556 3557 3558
	if (rc)
		return rc;

3559
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3560 3561 3562 3563
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3564
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3565 3566
}

3567 3568
static int selinux_task_movememory(struct task_struct *p)
{
3569
	return current_has_perm(p, PROCESS__SETSCHED);
3570 3571
}

3572 3573
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3574 3575 3576 3577 3578 3579 3580 3581
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3582
	if (secid)
3583 3584
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3585
	else
3586
		rc = current_has_perm(p, perm);
3587
	return rc;
L
Linus Torvalds 已提交
3588 3589 3590 3591
}

static int selinux_task_wait(struct task_struct *p)
{
3592
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3593 3594 3595 3596 3597 3598
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3599
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3600

3601
	isec->sid = sid;
L
Linus Torvalds 已提交
3602 3603 3604 3605
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3606
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3607
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3608 3609 3610 3611
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3612
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3613 3614 3615 3616 3617 3618 3619 3620
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3621 3622
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3623 3624
	ret = 0;

3625 3626 3627
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3628
	switch (ih->protocol) {
3629 3630
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3631

3632 3633
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3634 3635 3636 3637 3638 3639

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

3640 3641
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3642
		break;
3643 3644 3645 3646 3647 3648 3649 3650
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3651
		offset += ihlen;
3652
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3653
		if (uh == NULL)
3654
			break;
L
Linus Torvalds 已提交
3655

3656 3657
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3658 3659
		break;
	}
L
Linus Torvalds 已提交
3660

J
James Morris 已提交
3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671
	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;

3672 3673
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3674
		break;
3675
	}
J
James Morris 已提交
3676

3677 3678 3679
	default:
		break;
	}
L
Linus Torvalds 已提交
3680 3681 3682 3683 3684 3685 3686
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3687
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3688
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3689 3690 3691 3692
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3693
	__be16 frag_off;
L
Linus Torvalds 已提交
3694

3695
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3696 3697 3698 3699
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3700 3701
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3702 3703 3704 3705
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3706
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3707 3708 3709
	if (offset < 0)
		goto out;

3710 3711 3712
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3713 3714
	switch (nexthdr) {
	case IPPROTO_TCP: {
3715
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3716 3717 3718 3719 3720

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

3721 3722
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3723 3724 3725 3726 3727 3728 3729 3730 3731 3732
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3733 3734
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3735 3736 3737
		break;
	}

J
James Morris 已提交
3738 3739 3740 3741 3742 3743 3744
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3745 3746
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3747
		break;
3748
	}
J
James Morris 已提交
3749

L
Linus Torvalds 已提交
3750 3751 3752 3753 3754 3755 3756 3757 3758 3759
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3760
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3761
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3762
{
3763 3764
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3765

3766
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3767
	case PF_INET:
3768
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3769 3770
		if (ret)
			goto parse_error;
3771 3772
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3773
		goto okay;
L
Linus Torvalds 已提交
3774 3775 3776

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3777
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3778 3779
		if (ret)
			goto parse_error;
3780 3781
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3782
		goto okay;
L
Linus Torvalds 已提交
3783 3784
#endif	/* IPV6 */
	default:
3785 3786
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3787 3788
	}

3789 3790 3791 3792
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3793
	return ret;
3794 3795 3796 3797 3798

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3799 3800
}

3801
/**
3802
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3803
 * @skb: the packet
3804
 * @family: protocol family
3805
 * @sid: the packet's peer label SID
3806 3807
 *
 * Description:
3808 3809 3810 3811 3812 3813
 * 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.
3814 3815
 *
 */
3816
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3817
{
3818
	int err;
3819 3820
	u32 xfrm_sid;
	u32 nlbl_sid;
3821
	u32 nlbl_type;
3822

3823
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3824 3825 3826 3827 3828
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3829

3830 3831 3832 3833 3834
	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");
3835
		return -EACCES;
3836
	}
3837 3838

	return 0;
3839 3840
}

3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864
/**
 * 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
3865
/* socket security operations */
3866

3867 3868
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3869
{
3870 3871 3872 3873 3874 3875 3876
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3877 3878
}

3879
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3880
{
3881
	struct sk_security_struct *sksec = sk->sk_security;
3882
	struct common_audit_data ad;
3883
	struct lsm_network_audit net = {0,};
3884
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3885

3886 3887
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3888

3889
	ad.type = LSM_AUDIT_DATA_NET;
3890 3891
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3892

3893
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3894 3895 3896 3897 3898
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3899
	const struct task_security_struct *tsec = current_security();
3900
	u32 newsid;
3901
	u16 secclass;
3902
	int rc;
L
Linus Torvalds 已提交
3903 3904

	if (kern)
3905
		return 0;
3906 3907

	secclass = socket_type_to_security_class(family, type, protocol);
3908 3909 3910 3911
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3912
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3913 3914
}

V
Venkat Yekkirala 已提交
3915 3916
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3917
{
3918
	const struct task_security_struct *tsec = current_security();
3919
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3920
	struct sk_security_struct *sksec;
3921 3922
	int err = 0;

3923 3924
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3925 3926
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3927 3928 3929 3930 3931
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3932

L
Linus Torvalds 已提交
3933 3934
	isec->initialized = 1;

3935 3936 3937
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3938
		sksec->sclass = isec->sclass;
3939
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3940 3941
	}

V
Venkat Yekkirala 已提交
3942
	return err;
L
Linus Torvalds 已提交
3943 3944 3945 3946 3947 3948 3949 3950
}

/* 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)
{
3951
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3952 3953 3954
	u16 family;
	int err;

3955
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3956 3957 3958 3959 3960
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3961 3962
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3963
	 */
3964
	family = sk->sk_family;
L
Linus Torvalds 已提交
3965 3966
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3967
		struct sk_security_struct *sksec = sk->sk_security;
3968
		struct common_audit_data ad;
3969
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3970 3971 3972
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3973
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984

		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;
		}

3985 3986 3987
		if (snum) {
			int low, high;

3988
			inet_get_local_port_range(sock_net(sk), &low, &high);
3989 3990

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
3991 3992
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3993 3994
				if (err)
					goto out;
3995
				ad.type = LSM_AUDIT_DATA_NET;
3996 3997 3998
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
3999 4000
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4001 4002 4003 4004
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4005
		}
4006

4007
		switch (sksec->sclass) {
4008
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4009 4010
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4011

4012
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4013 4014
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4015 4016 4017 4018 4019

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4020 4021 4022 4023
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4024

4025
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4026 4027
		if (err)
			goto out;
4028

4029
		ad.type = LSM_AUDIT_DATA_NET;
4030 4031 4032
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4033 4034

		if (family == PF_INET)
4035
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4036
		else
4037
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4038

4039 4040
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4041 4042 4043 4044 4045 4046 4047 4048 4049
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4050
	struct sock *sk = sock->sk;
4051
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4052 4053
	int err;

4054
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4055 4056 4057 4058
	if (err)
		return err;

	/*
J
James Morris 已提交
4059
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4060
	 */
4061 4062
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4063
		struct common_audit_data ad;
4064
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4065 4066 4067
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4068
		u32 sid, perm;
L
Linus Torvalds 已提交
4069 4070 4071

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4072
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4073 4074 4075 4076
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4077
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4078 4079 4080 4081
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4082
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4083 4084 4085
		if (err)
			goto out;

4086
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4087 4088
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4089
		ad.type = LSM_AUDIT_DATA_NET;
4090 4091 4092
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4093
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4094 4095 4096 4097
		if (err)
			goto out;
	}

4098 4099
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4100 4101 4102 4103 4104 4105
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4106
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4107 4108 4109 4110 4111 4112 4113 4114
}

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

4115
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129
	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,
4130
				  int size)
L
Linus Torvalds 已提交
4131
{
4132
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4133 4134 4135 4136 4137
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4138
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4139 4140 4141 4142
}

static int selinux_socket_getsockname(struct socket *sock)
{
4143
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4144 4145 4146 4147
}

static int selinux_socket_getpeername(struct socket *sock)
{
4148
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4149 4150
}

4151
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4152
{
4153 4154
	int err;

4155
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4156 4157 4158 4159
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4160 4161 4162 4163 4164
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4165
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4166 4167 4168 4169
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4170
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4171 4172
}

4173 4174
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4175 4176
					      struct sock *newsk)
{
4177 4178
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4179
	struct sk_security_struct *sksec_new = newsk->sk_security;
4180
	struct common_audit_data ad;
4181
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4182 4183
	int err;

4184
	ad.type = LSM_AUDIT_DATA_NET;
4185 4186
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4187

4188 4189
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4190 4191 4192 4193 4194
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4195 4196 4197 4198 4199
	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;
4200

4201 4202 4203 4204
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4205 4206 4207 4208 4209
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4210 4211
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4212
	struct common_audit_data ad;
4213
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4214

4215
	ad.type = LSM_AUDIT_DATA_NET;
4216 4217
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4218

4219 4220
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4221 4222
}

4223 4224
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4225
				    struct common_audit_data *ad)
4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245
{
	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);
}

4246
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4247
				       u16 family)
4248
{
4249
	int err = 0;
4250 4251
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4252
	struct common_audit_data ad;
4253
	struct lsm_network_audit net = {0,};
4254 4255
	char *addrp;

4256
	ad.type = LSM_AUDIT_DATA_NET;
4257 4258 4259
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4260 4261 4262
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4263

4264
	if (selinux_secmark_enabled()) {
4265
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4266
				   PACKET__RECV, &ad);
4267 4268 4269
		if (err)
			return err;
	}
4270

4271 4272 4273 4274
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4275

4276 4277 4278 4279 4280
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4281
	int err;
4282
	struct sk_security_struct *sksec = sk->sk_security;
4283 4284
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4285
	struct common_audit_data ad;
4286
	struct lsm_network_audit net = {0,};
4287
	char *addrp;
4288 4289
	u8 secmark_active;
	u8 peerlbl_active;
4290 4291

	if (family != PF_INET && family != PF_INET6)
4292
		return 0;
4293 4294

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4295
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4296 4297
		family = PF_INET;

4298 4299 4300 4301
	/* 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. */
4302
	if (!selinux_policycap_netpeer)
4303 4304 4305
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4306
	peerlbl_active = selinux_peerlbl_enabled();
4307 4308 4309
	if (!secmark_active && !peerlbl_active)
		return 0;

4310
	ad.type = LSM_AUDIT_DATA_NET;
4311 4312 4313
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4314
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4315
	if (err)
4316
		return err;
4317

4318
	if (peerlbl_active) {
4319 4320 4321
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4322 4323
		if (err)
			return err;
4324
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4325
					       peer_sid, &ad);
4326 4327
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4328
			return err;
4329
		}
4330 4331
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4332
		if (err) {
4333
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4334 4335
			return err;
		}
4336 4337
	}

4338
	if (secmark_active) {
4339 4340 4341 4342 4343 4344
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4345
	return err;
L
Linus Torvalds 已提交
4346 4347
}

C
Catherine Zhang 已提交
4348 4349
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4350 4351 4352 4353
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4354
	struct sk_security_struct *sksec = sock->sk->sk_security;
4355
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4356

4357 4358
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4359
		peer_sid = sksec->peer_sid;
4360 4361
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4362

C
Catherine Zhang 已提交
4363
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4364
	if (err)
4365
		return err;
L
Linus Torvalds 已提交
4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381

	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;
}

4382
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4383
{
4384
	u32 peer_secid = SECSID_NULL;
4385
	u16 family;
C
Catherine Zhang 已提交
4386

4387 4388 4389 4390 4391
	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)
4392 4393 4394 4395 4396
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4397
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4398
	else if (skb)
4399
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4400

4401
out:
4402
	*secid = peer_secid;
4403 4404 4405
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4406 4407
}

A
Al Viro 已提交
4408
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4409
{
4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421
	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
4422 4423 4424 4425
}

static void selinux_sk_free_security(struct sock *sk)
{
4426 4427 4428 4429 4430
	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
4431 4432
}

4433
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4434
{
4435 4436
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4437

4438 4439 4440
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4441

4442
	selinux_netlbl_sk_security_reset(newsksec);
4443 4444
}

V
Venkat Yekkirala 已提交
4445
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4446
{
4447
	if (!sk)
V
Venkat Yekkirala 已提交
4448
		*secid = SECINITSID_ANY_SOCKET;
4449 4450
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4451

V
Venkat Yekkirala 已提交
4452
		*secid = sksec->sid;
4453
	}
4454 4455
}

4456
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4457 4458 4459 4460
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4461 4462 4463
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4464
	sksec->sclass = isec->sclass;
4465 4466
}

4467 4468
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4469 4470 4471
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4472
	u16 family = req->rsk_ops->family;
4473
	u32 connsid;
4474 4475
	u32 peersid;

4476
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4477 4478
	if (err)
		return err;
4479 4480 4481 4482 4483
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4484

4485
	return selinux_netlbl_inet_conn_request(req, family);
4486 4487
}

4488 4489
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4490 4491 4492 4493
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4494
	newsksec->peer_sid = req->peer_secid;
4495 4496 4497 4498
	/* 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. */
4499

P
Paul Moore 已提交
4500 4501
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4502
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4503 4504
}

4505
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4506
{
4507
	u16 family = sk->sk_family;
4508 4509
	struct sk_security_struct *sksec = sk->sk_security;

4510 4511 4512 4513 4514
	/* 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);
4515 4516
}

4517 4518 4519 4520 4521
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542
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);
}

4543 4544
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4545
{
4546
	fl->flowi_secid = req->secid;
4547 4548
}

4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566
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);
}

4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581
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);
}

4582
static int selinux_tun_dev_attach_queue(void *security)
4583
{
4584 4585 4586 4587 4588 4589 4590 4591 4592
	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;
4593 4594 4595 4596 4597 4598 4599 4600 4601
	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 */

4602
	sksec->sid = tunsec->sid;
4603
	sksec->sclass = SECCLASS_TUN_SOCKET;
4604 4605

	return 0;
4606 4607
}

4608
static int selinux_tun_dev_open(void *security)
4609
{
4610
	struct tun_security_struct *tunsec = security;
4611 4612 4613
	u32 sid = current_sid();
	int err;

4614
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4615 4616 4617 4618 4619 4620 4621
			   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;
4622
	tunsec->sid = sid;
4623 4624 4625 4626

	return 0;
}

L
Linus Torvalds 已提交
4627 4628 4629 4630 4631
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4632
	struct sk_security_struct *sksec = sk->sk_security;
4633

4634
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4635 4636 4637
		err = -EINVAL;
		goto out;
	}
4638
	nlh = nlmsg_hdr(skb);
4639

4640
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4641 4642
	if (err) {
		if (err == -EINVAL) {
4643
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4644 4645
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4646
				  nlh->nlmsg_type, sksec->sclass);
4647
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4648 4649 4650 4651 4652 4653 4654 4655 4656
				err = 0;
		}

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

4657
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4658 4659 4660 4661 4662 4663
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4664 4665
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4666
{
4667
	int err;
4668 4669
	char *addrp;
	u32 peer_sid;
4670
	struct common_audit_data ad;
4671
	struct lsm_network_audit net = {0,};
4672
	u8 secmark_active;
4673
	u8 netlbl_active;
4674
	u8 peerlbl_active;
4675

4676 4677
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4678

4679
	secmark_active = selinux_secmark_enabled();
4680
	netlbl_active = netlbl_enabled();
4681
	peerlbl_active = selinux_peerlbl_enabled();
4682 4683
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4684

4685 4686 4687
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4688
	ad.type = LSM_AUDIT_DATA_NET;
4689 4690 4691
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4692 4693 4694
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4695 4696 4697 4698 4699
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4700
			return NF_DROP;
4701 4702
		}
	}
4703 4704 4705 4706 4707 4708

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

4709 4710 4711 4712 4713 4714 4715 4716
	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;

4717 4718 4719
	return NF_ACCEPT;
}

4720
static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4721 4722 4723 4724 4725 4726 4727 4728 4729
					 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)
4730
static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4731 4732 4733 4734 4735 4736 4737 4738 4739
					 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 */

4740 4741 4742
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4743
	struct sock *sk;
4744 4745 4746 4747 4748 4749 4750 4751
	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 */
4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772
	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;
4773 4774 4775 4776 4777 4778 4779 4780 4781
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4782
static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4783 4784 4785 4786 4787 4788 4789 4790
					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);
}

4791 4792
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4793
						u16 family)
4794 4795 4796
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4797
	struct common_audit_data ad;
4798
	struct lsm_network_audit net = {0,};
4799 4800
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4801

4802 4803 4804 4805
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4806
	ad.type = LSM_AUDIT_DATA_NET;
4807 4808 4809
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4810 4811 4812
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4813
	if (selinux_secmark_enabled())
4814
		if (avc_has_perm(sksec->sid, skb->secmark,
4815
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4816
			return NF_DROP_ERR(-ECONNREFUSED);
4817

4818 4819
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4820 4821

	return NF_ACCEPT;
4822 4823
}

4824 4825
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4826
{
4827 4828
	u32 secmark_perm;
	u32 peer_sid;
4829
	struct sock *sk;
4830
	struct common_audit_data ad;
4831
	struct lsm_network_audit net = {0,};
4832 4833 4834
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4835

4836 4837 4838 4839
	/* 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. */
4840
	if (!selinux_policycap_netpeer)
4841
		return selinux_ip_postroute_compat(skb, ifindex, family);
4842 4843 4844 4845 4846 4847 4848 4849

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

	sk = skb->sk;

4850
#ifdef CONFIG_XFRM
4851 4852 4853 4854 4855
	/* 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
4856 4857 4858 4859 4860 4861 4862 4863
	 *       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))
4864
		return NF_ACCEPT;
4865
#endif
4866

4867
	if (sk == NULL) {
4868 4869 4870 4871
		/* 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. */
4872 4873
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4874
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4875
				return NF_DROP;
4876 4877
		} else {
			secmark_perm = PACKET__SEND;
4878
			peer_sid = SECINITSID_KERNEL;
4879
		}
4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893
	} 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;
4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912
		/* 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);
			}
		}
4913 4914 4915
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4916
	} else {
4917 4918
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4919 4920 4921 4922
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4923

4924
	ad.type = LSM_AUDIT_DATA_NET;
4925 4926 4927
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4928
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4929
		return NF_DROP;
4930

4931 4932 4933
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4934
			return NF_DROP_ERR(-ECONNREFUSED);
4935 4936 4937 4938 4939 4940

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4941
			return NF_DROP;
4942 4943
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4944
			return NF_DROP_ERR(-ECONNREFUSED);
4945 4946

		if (sel_netnode_sid(addrp, family, &node_sid))
4947
			return NF_DROP;
4948 4949
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4950
			return NF_DROP_ERR(-ECONNREFUSED);
4951
	}
4952

4953
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4954 4955
}

4956
static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4957 4958 4959 4960
					   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
4961
{
4962
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4963 4964 4965
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4966
static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
4967 4968 4969 4970
					   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
4971
{
4972
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4973 4974 4975 4976 4977 4978 4979 4980 4981
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4982
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4983 4984 4985
	if (err)
		return err;

4986
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4987 4988 4989 4990 4991 4992 4993
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4994
	u32 sid;
L
Linus Torvalds 已提交
4995

J
James Morris 已提交
4996
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4997 4998 4999
	if (!isec)
		return -ENOMEM;

5000
	sid = task_sid(task);
L
Linus Torvalds 已提交
5001
	isec->sclass = sclass;
5002
	isec->sid = sid;
L
Linus Torvalds 已提交
5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018
	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
5019
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037
	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,
5038
			u32 perms)
L
Linus Torvalds 已提交
5039 5040
{
	struct ipc_security_struct *isec;
5041
	struct common_audit_data ad;
5042
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5043 5044 5045

	isec = ipc_perms->security;

5046
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5047 5048
	ad.u.ipc_id = ipc_perms->key;

5049
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065
}

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;
5066
	struct common_audit_data ad;
5067
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5068 5069 5070 5071 5072 5073 5074 5075
	int rc;

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

	isec = msq->q_perm.security;

5076
	ad.type = LSM_AUDIT_DATA_IPC;
5077
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5078

5079
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095
			  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;
5096
	struct common_audit_data ad;
5097
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5098 5099 5100

	isec = msq->q_perm.security;

5101
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5102 5103
	ad.u.ipc_id = msq->q_perm.key;

5104
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5105 5106 5107 5108 5109 5110 5111 5112
			    MSGQ__ASSOCIATE, &ad);
}

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

5113
	switch (cmd) {
L
Linus Torvalds 已提交
5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131
	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;
	}

5132
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5133 5134 5135 5136 5137 5138 5139
	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;
5140
	struct common_audit_data ad;
5141
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153 5154
	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
		 */
5155
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5156
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5157 5158 5159 5160
		if (rc)
			return rc;
	}

5161
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5162 5163 5164
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5165
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5166 5167 5168
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5169 5170
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5171 5172
	if (!rc)
		/* Can the message be put in the queue? */
5173 5174
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5175 5176 5177 5178 5179 5180 5181 5182 5183 5184

	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;
5185
	struct common_audit_data ad;
5186
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5187 5188 5189 5190 5191
	int rc;

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

5192
	ad.type = LSM_AUDIT_DATA_IPC;
5193
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5194

5195
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5196 5197
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5198
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5199 5200 5201 5202 5203 5204 5205 5206
				  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;
5207
	struct common_audit_data ad;
5208
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5209 5210 5211 5212 5213 5214 5215 5216
	int rc;

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

	isec = shp->shm_perm.security;

5217
	ad.type = LSM_AUDIT_DATA_IPC;
5218
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5219

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

	isec = shp->shm_perm.security;

5242
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5243 5244
	ad.u.ipc_id = shp->shm_perm.key;

5245
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5246 5247 5248 5249 5250 5251 5252 5253 5254
			    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;

5255
	switch (cmd) {
L
Linus Torvalds 已提交
5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277
	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;
	}

5278
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291
	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;

5292
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5293 5294 5295 5296 5297 5298
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5299
	struct common_audit_data ad;
5300
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5301 5302 5303 5304 5305 5306 5307 5308
	int rc;

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

	isec = sma->sem_perm.security;

5309
	ad.type = LSM_AUDIT_DATA_IPC;
5310
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5311

5312
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328
			  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;
5329
	struct common_audit_data ad;
5330
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5331 5332 5333

	isec = sma->sem_perm.security;

5334
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5335 5336
	ad.u.ipc_id = sma->sem_perm.key;

5337
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5338 5339 5340 5341 5342 5343 5344 5345 5346
			    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;

5347
	switch (cmd) {
L
Linus Torvalds 已提交
5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378
	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;
	}

5379
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392
	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;

5393
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408
}

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;

5409
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5410 5411
}

5412 5413 5414 5415 5416 5417
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5418
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5419 5420 5421 5422 5423 5424
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5425
			       char *name, char **value)
L
Linus Torvalds 已提交
5426
{
5427
	const struct task_security_struct *__tsec;
5428
	u32 sid;
L
Linus Torvalds 已提交
5429
	int error;
5430
	unsigned len;
L
Linus Torvalds 已提交
5431 5432

	if (current != p) {
5433
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5434 5435 5436 5437
		if (error)
			return error;
	}

5438 5439
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5440 5441

	if (!strcmp(name, "current"))
5442
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5443
	else if (!strcmp(name, "prev"))
5444
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5445
	else if (!strcmp(name, "exec"))
5446
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5447
	else if (!strcmp(name, "fscreate"))
5448
		sid = __tsec->create_sid;
5449
	else if (!strcmp(name, "keycreate"))
5450
		sid = __tsec->keycreate_sid;
5451
	else if (!strcmp(name, "sockcreate"))
5452
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5453
	else
5454 5455
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5456 5457 5458 5459

	if (!sid)
		return 0;

5460 5461 5462 5463
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5464 5465 5466 5467

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5468 5469 5470 5471 5472 5473
}

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
5474
	struct task_struct *tracer;
D
David Howells 已提交
5475 5476
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491
	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"))
5492
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5493
	else if (!strcmp(name, "fscreate"))
5494
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5495
	else if (!strcmp(name, "keycreate"))
5496
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5497
	else if (!strcmp(name, "sockcreate"))
5498
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5499
	else if (!strcmp(name, "current"))
5500
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
	if (size && str[1] && str[1] != '\n') {
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
		error = security_context_to_sid(value, size, &sid);
5513
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528
			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);

5529
				return error;
5530
			}
5531 5532 5533
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5534 5535 5536 5537
		if (error)
			return error;
	}

D
David Howells 已提交
5538 5539 5540 5541
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5542 5543 5544
	/* 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
5545
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5546 5547
	   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
5548 5549
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5550
		tsec->exec_sid = sid;
D
David Howells 已提交
5551
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5552
		tsec->create_sid = sid;
D
David Howells 已提交
5553
	} else if (!strcmp(name, "keycreate")) {
5554 5555
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5556
			goto abort_change;
5557
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5558
	} else if (!strcmp(name, "sockcreate")) {
5559
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5560 5561
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5562
		if (sid == 0)
D
David Howells 已提交
5563 5564 5565 5566
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5567
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5568 5569 5570
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5571
		}
L
Linus Torvalds 已提交
5572 5573 5574

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5575
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5576
		if (error)
D
David Howells 已提交
5577
			goto abort_change;
L
Linus Torvalds 已提交
5578 5579 5580

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5581
		ptsid = 0;
5582
		rcu_read_lock();
5583
		tracer = ptrace_parent(p);
D
David Howells 已提交
5584 5585
		if (tracer)
			ptsid = task_sid(tracer);
5586
		rcu_read_unlock();
D
David Howells 已提交
5587 5588 5589 5590

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5591
			if (error)
D
David Howells 已提交
5592
				goto abort_change;
L
Linus Torvalds 已提交
5593 5594
		}

D
David Howells 已提交
5595 5596 5597 5598 5599 5600 5601
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5602
	return size;
D
David Howells 已提交
5603 5604 5605 5606

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5607 5608
}

5609 5610 5611 5612 5613
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5614 5615 5616 5617 5618
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5619
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5620 5621 5622 5623
{
	return security_context_to_sid(secdata, seclen, secid);
}

5624 5625
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5626
	kfree(secdata);
5627 5628
}

5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654
/*
 *	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;
}
5655 5656
#ifdef CONFIG_KEYS

D
David Howells 已提交
5657
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5658
			     unsigned long flags)
5659
{
D
David Howells 已提交
5660
	const struct task_security_struct *tsec;
5661 5662 5663 5664 5665 5666
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5667 5668 5669
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5670
	else
D
David Howells 已提交
5671
		ksec->sid = tsec->sid;
5672

5673
	k->security = ksec;
5674 5675 5676 5677 5678 5679 5680 5681 5682 5683 5684 5685
	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
5686 5687
				  const struct cred *cred,
				  key_perm_t perm)
5688 5689 5690
{
	struct key *key;
	struct key_security_struct *ksec;
5691
	u32 sid;
5692 5693 5694 5695 5696 5697 5698

	/* 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
5699
	sid = cred_sid(cred);
5700 5701 5702 5703 5704

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5705 5706
}

5707 5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720
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;
}

5721 5722
#endif

L
Linus Torvalds 已提交
5723
static struct security_operations selinux_ops = {
5724 5725
	.name =				"selinux",

5726
	.ptrace_access_check =		selinux_ptrace_access_check,
5727
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5728
	.capget =			selinux_capget,
D
David Howells 已提交
5729
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5730 5731 5732 5733 5734 5735 5736 5737
	.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,

5738 5739 5740
	.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
5741 5742 5743 5744 5745
	.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,
5746
	.sb_remount =			selinux_sb_remount,
5747
	.sb_kern_mount =		selinux_sb_kern_mount,
5748
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5749 5750 5751
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5752
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5753
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5754 5755
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5756
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5757 5758 5759

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5760
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778
	.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,
5779 5780 5781
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5782
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5783 5784 5785 5786 5787

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5788 5789
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5790 5791 5792 5793 5794 5795 5796
	.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,

5797
	.file_open =			selinux_file_open,
5798

L
Linus Torvalds 已提交
5799
	.task_create =			selinux_task_create,
5800
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5801
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5802
	.cred_prepare =			selinux_cred_prepare,
5803
	.cred_transfer =		selinux_cred_transfer,
5804 5805
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5806
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5807 5808
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5809
	.task_getsid =			selinux_task_getsid,
5810
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5811
	.task_setnice =			selinux_task_setnice,
5812
	.task_setioprio =		selinux_task_setioprio,
5813
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5814 5815 5816
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5817
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5818 5819
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5820
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5821 5822

	.ipc_permission =		selinux_ipc_permission,
5823
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840

	.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,

5841 5842
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5843 5844 5845 5846
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5847
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5848

5849 5850
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5851

5852
	.ismaclabel =			selinux_ismaclabel,
5853
	.secid_to_secctx =		selinux_secid_to_secctx,
5854
	.secctx_to_secid =		selinux_secctx_to_secid,
5855
	.release_secctx =		selinux_release_secctx,
5856 5857 5858
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5859

5860
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874 5875 5876
	.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
5877 5878
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5879 5880
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5881
	.sk_clone_security =		selinux_sk_clone_security,
5882
	.sk_getsecid =			selinux_sk_getsecid,
5883 5884 5885
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5886
	.inet_conn_established =	selinux_inet_conn_established,
5887 5888 5889
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5890
	.req_classify_flow =		selinux_req_classify_flow,
5891 5892
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5893
	.tun_dev_create =		selinux_tun_dev_create,
5894
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5895
	.tun_dev_attach =		selinux_tun_dev_attach,
5896
	.tun_dev_open =			selinux_tun_dev_open,
5897
	.skb_owned_by =			selinux_skb_owned_by,
5898 5899 5900 5901 5902

#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
5903
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5904 5905
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5906
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5907
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5908
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5909 5910
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5911
#endif
5912 5913

#ifdef CONFIG_KEYS
5914 5915 5916
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5917
	.key_getsecurity =		selinux_key_getsecurity,
5918
#endif
5919 5920 5921 5922 5923 5924 5925

#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
5926 5927 5928 5929
};

static __init int selinux_init(void)
{
5930 5931 5932 5933 5934
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5935 5936 5937 5938 5939 5940 5941 5942
	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
5943
	cred_init_security();
L
Linus Torvalds 已提交
5944

5945 5946
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5947 5948
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5949
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5950 5951
	avc_init();

5952
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5953 5954
		panic("SELinux: Unable to register with kernel.\n");

5955
	if (selinux_enforcing)
5956
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5957
	else
5958
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5959

L
Linus Torvalds 已提交
5960 5961 5962
	return 0;
}

5963 5964 5965 5966 5967
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5968 5969
void selinux_complete_init(void)
{
5970
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5971 5972

	/* Set up any superblocks initialized prior to the policy load. */
5973
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5974
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5975 5976 5977 5978 5979 5980
}

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

5981
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5982

5983 5984 5985 5986
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5987
		.pf =		NFPROTO_IPV4,
5988 5989 5990 5991 5992 5993
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
5994
		.pf =		NFPROTO_IPV4,
5995 5996
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5997 5998 5999 6000
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6001
		.pf =		NFPROTO_IPV4,
6002 6003
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6004
	}
L
Linus Torvalds 已提交
6005 6006 6007 6008
};

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

6009 6010 6011 6012
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6013
		.pf =		NFPROTO_IPV6,
6014 6015 6016 6017 6018 6019
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6020
		.pf =		NFPROTO_IPV6,
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		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
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};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
6034 6035 6036

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

6037 6038 6039
	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);
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6042 6043 6044
	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);
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#endif	/* IPV6 */
6046

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out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6056
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
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6058
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6060
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
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#endif	/* IPV6 */
}
#endif

6065
#else /* CONFIG_NETFILTER */
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6071
#endif /* CONFIG_NETFILTER */
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6074 6075
static int selinux_disabled;

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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;
6091
	selinux_enabled = 0;
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6093
	reset_security_ops();
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6095 6096 6097
	/* Try to destroy the avc node cache */
	avc_disable();

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	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif