hooks.c 151.6 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

#include <linux/init.h>
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#include <linux/kd.h>
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#include <linux/kernel.h>
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#include <linux/tracehook.h>
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#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
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#include <linux/proc_fs.h>
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#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
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#include <linux/dcache.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
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#include <net/ip.h>		/* for local_port_range[] */
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#include <net/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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static int selinux_netcache_avc_callback(u32 event)
{
	if (event == AVC_CALLBACK_RESET) {
		sel_netif_flush();
		sel_netnode_flush();
		sel_netport_flush();
		synchronize_net();
	}
	return 0;
}

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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	/*
	 * The inode may still be referenced in a path walk and
	 * a call to selinux_inode_permission() can be made
	 * after inode_free_security() is called. Ideally, the VFS
	 * wouldn't do this, but fixing that is a much harder
	 * job. For now, simply free the i_security via RCU, and
	 * leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&isec->rcu, inode_free_rcu);
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}

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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static const char *labeling_behaviors[7] = {
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	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
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	"uses native labeling",
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};

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

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

enum {
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	Opt_error = -1,
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	Opt_context = 1,
	Opt_fscontext = 2,
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	Opt_defcontext = 3,
	Opt_rootcontext = 4,
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	Opt_labelsupport = 5,
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	Opt_nextmntopt = 6,
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};

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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

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

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static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
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			const struct cred *cred)
372
{
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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)
389
{
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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;
569 570 571 572
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
573

574 575 576
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
577 578
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
579
	}
580
	if (sbsec->flags & SBLABEL_MNT) {
581
		opts->mnt_opts[i] = NULL;
582
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
583
	}
L
Linus Torvalds 已提交
584

585
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
586

587 588 589
	return 0;

out_free:
590
	security_free_mnt_opts(opts);
591 592
	return rc;
}
L
Linus Torvalds 已提交
593

594 595 596
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
597 598
	char mnt_flags = sbsec->flags & SE_MNTMASK;

599
	/* check if the old mount command had the same options */
600
	if (sbsec->flags & SE_SBINITIALIZED)
601 602 603 604 605 606 607
		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
	 */
608 609
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
610 611 612
			return 1;
	return 0;
}
613

614 615 616 617
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
618
static int selinux_set_mnt_opts(struct super_block *sb,
619 620 621
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
622
{
623
	const struct cred *cred = current_cred();
624 625
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
626
	const char *name = sb->s_type->name;
627 628
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
629 630
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
631 632 633
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
634 635 636 637 638 639 640 641 642 643 644

	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
645 646
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
647
		goto out;
648
	}
649 650 651 652 653 654
	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
655

656 657 658 659 660 661 662 663 664 665 666
	/*
	 * 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)
	 */
667
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
668
	    && (num_opts == 0))
669
		goto out;
670

671 672 673 674 675 676 677
	/*
	 * 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;
678

679
		if (flags[i] == SBLABEL_MNT)
680
			continue;
681
		rc = security_context_to_sid(mount_options[i],
682
					     strlen(mount_options[i]), &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
683 684
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
685 686
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730
			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
731
		}
732 733
	}

734
	if (sbsec->flags & SE_SBINITIALIZED) {
735
		/* previously mounted with options, but not on this attempt? */
736
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
737 738 739 740 741
			goto out_double_mount;
		rc = 0;
		goto out;
	}

742
	if (strcmp(sb->s_type->name, "proc") == 0)
743
		sbsec->flags |= SE_SBPROC;
744

745 746 747 748 749
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
750
		rc = security_fs_use(sb);
751 752 753 754 755 756
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
757 758 759
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
760
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
761
		if (rc)
762
			goto out;
L
Linus Torvalds 已提交
763

764
		sbsec->sid = fscontext_sid;
765 766 767 768 769 770 771
	}

	/*
	 * 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.
	 */
772 773 774 775 776
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

777 778
	if (context_sid) {
		if (!fscontext_sid) {
779 780
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
781
			if (rc)
782 783
				goto out;
			sbsec->sid = context_sid;
784
		} else {
785 786
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
787
			if (rc)
788
				goto out;
789
		}
790 791
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
792

793
		sbsec->mntpoint_sid = context_sid;
794
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
795 796
	}

797
	if (rootcontext_sid) {
798 799
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
800
		if (rc)
801
			goto out;
802

803 804
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
805 806
	}

807
	if (defcontext_sid) {
808 809
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
810 811 812 813
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
814 815
		}

816 817
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
818
							     sbsec, cred);
819 820 821
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
822

823
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
824 825
	}

826
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
827
out:
828
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
829
	return rc;
830 831 832
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
833
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
834
	goto out;
L
Linus Torvalds 已提交
835 836
}

837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867
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,
868
					struct super_block *newsb)
L
Linus Torvalds 已提交
869
{
870 871
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
872

873 874 875
	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
876

877 878
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
879
	 * mount options.  thus we can safely deal with this superblock later
880
	 */
881
	if (!ss_initialized)
882
		return 0;
883 884

	/* how can we clone if the old one wasn't set up?? */
885
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
886

887
	/* if fs is reusing a sb, make sure that the contexts match */
888
	if (newsbsec->flags & SE_SBINITIALIZED)
889
		return selinux_cmp_sb_context(oldsb, newsb);
890

891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909
	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
910
	}
911 912 913 914 915
	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
916

917
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
918 919
	}

920 921
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
922
	return 0;
923 924
}

925 926
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
927
{
928
	char *p;
929 930
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
931
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
932

933
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
934

935 936 937 938
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
939

940 941
		if (!*p)
			continue;
L
Linus Torvalds 已提交
942

943
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
944

945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996
		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;
997 998
		case Opt_labelsupport:
			break;
999 1000 1001 1002
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
1003 1004 1005

		}
	}
1006

1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
	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;
	}

1018
	if (fscontext) {
1019 1020
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1021 1022
	}
	if (context) {
1023 1024
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1025 1026
	}
	if (rootcontext) {
1027 1028
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1029 1030
	}
	if (defcontext) {
1031 1032
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1033 1034
	}

1035 1036 1037
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1038 1039 1040 1041 1042
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1043 1044
	return rc;
}
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065
/*
 * 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:
1066
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1067 1068 1069 1070 1071

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1072

A
Adrian Bunk 已提交
1073 1074
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1075 1076 1077 1078 1079
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1080 1081 1082 1083 1084 1085
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099

		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;
1100
		case SBLABEL_MNT:
1101 1102 1103
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1104 1105
		default:
			BUG();
1106
			return;
1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124
		};
		/* 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);
1125 1126 1127 1128
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1129
		return rc;
1130
	}
1131 1132 1133 1134 1135 1136 1137 1138

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161
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;
}

1162 1163 1164 1165 1166 1167 1168 1169 1170 1171
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
1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187
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:
1188 1189 1190 1191
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1192
		case SOCK_DGRAM:
1193 1194 1195 1196
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1197 1198
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1199
		default:
L
Linus Torvalds 已提交
1200 1201 1202 1203 1204 1205 1206 1207 1208
			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;
1209
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222
			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;
1223 1224
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1225 1226 1227 1228 1229 1230 1231
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1232 1233
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1234 1235 1236 1237 1238 1239
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1240
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1241 1242 1243
				u16 tclass,
				u32 *sid)
{
1244 1245
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1246

1247
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1248 1249 1250
	if (!buffer)
		return -ENOMEM;

1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262
	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
1263 1264 1265 1266 1267
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1268
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290
				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;

1291
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1292
	if (isec->initialized)
1293
		goto out_unlock;
L
Linus Torvalds 已提交
1294 1295

	sbsec = inode->i_sb->s_security;
1296
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1297 1298 1299 1300 1301 1302 1303
		/* 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);
1304
		goto out_unlock;
L
Linus Torvalds 已提交
1305 1306 1307
	}

	switch (sbsec->behavior) {
1308 1309
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325
	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) {
1326 1327 1328 1329 1330 1331 1332 1333 1334
			/*
			 * 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.
			 */
1335
			goto out_unlock;
L
Linus Torvalds 已提交
1336 1337 1338
		}

		len = INITCONTEXTLEN;
1339
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1340 1341 1342
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1343
			goto out_unlock;
L
Linus Torvalds 已提交
1344
		}
1345
		context[len] = '\0';
L
Linus Torvalds 已提交
1346 1347 1348
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1349 1350
			kfree(context);

L
Linus Torvalds 已提交
1351 1352 1353 1354 1355
			/* 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);
1356
				goto out_unlock;
L
Linus Torvalds 已提交
1357 1358
			}
			len = rc;
1359
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1360 1361 1362
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1363
				goto out_unlock;
L
Linus Torvalds 已提交
1364
			}
1365
			context[len] = '\0';
L
Linus Torvalds 已提交
1366 1367 1368 1369 1370 1371 1372
			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
1373
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1374
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1375 1376
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1377
				goto out_unlock;
L
Linus Torvalds 已提交
1378 1379 1380 1381 1382
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1383
			rc = security_context_to_sid_default(context, rc, &sid,
1384 1385
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1386
			if (rc) {
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399
				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
1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417
				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);
1418 1419
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1420
		if (rc)
1421
			goto out_unlock;
L
Linus Torvalds 已提交
1422 1423
		isec->sid = sid;
		break;
1424 1425 1426
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1427
	default:
1428
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1429 1430
		isec->sid = sbsec->sid;

1431
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458
			/* We must have a dentry to determine the label on
			 * procfs inodes */
			if (opt_dentry)
				/* Called from d_instantiate or
				 * d_splice_alias. */
				dentry = dget(opt_dentry);
			else
				/* Called from selinux_complete_init, try to
				 * find a dentry. */
				dentry = d_find_alias(inode);
			/*
			 * This can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as
			 * these will get fixed up the next time we go through
			 * inode_doinit() with a dentry, before these inodes
			 * could be used again by userspace.
			 */
			if (!dentry)
				goto out_unlock;
			isec->sclass = inode_mode_to_security_class(inode->i_mode);
			rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
			dput(dentry);
			if (rc)
				goto out_unlock;
			isec->sid = sid;
L
Linus Torvalds 已提交
1459 1460 1461 1462 1463 1464
		}
		break;
	}

	isec->initialized = 1;

1465 1466
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499
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
1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
/*
 * 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);
}

1513
/*
1514
 * Check permission between a pair of tasks, e.g. signal checks,
1515 1516
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1517
 * - this uses the default subjective creds of tsk1
1518 1519 1520
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1521 1522
			 u32 perms)
{
1523 1524
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1525

1526 1527 1528 1529 1530
	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
1531 1532
}

1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548
/*
 * 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);
}

1549 1550 1551 1552
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1553
/* Check whether a task is allowed to use a capability. */
1554
static int cred_has_capability(const struct cred *cred,
1555
			       int cap, int audit)
L
Linus Torvalds 已提交
1556
{
1557
	struct common_audit_data ad;
1558
	struct av_decision avd;
1559
	u16 sclass;
1560
	u32 sid = cred_sid(cred);
1561
	u32 av = CAP_TO_MASK(cap);
1562
	int rc;
L
Linus Torvalds 已提交
1563

1564
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1565 1566
	ad.u.cap = cap;

1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577
	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();
1578
		return -EINVAL;
1579
	}
1580

1581
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1582
	if (audit == SECURITY_CAP_AUDIT) {
1583
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1584 1585 1586
		if (rc2)
			return rc2;
	}
1587
	return rc;
L
Linus Torvalds 已提交
1588 1589 1590 1591 1592 1593
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1594
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1595

1596
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1597 1598 1599 1600 1601 1602
			    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). */
1603
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1604 1605
			  struct inode *inode,
			  u32 perms,
1606
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1607 1608
{
	struct inode_security_struct *isec;
1609
	u32 sid;
L
Linus Torvalds 已提交
1610

1611 1612
	validate_creds(cred);

1613
	if (unlikely(IS_PRIVATE(inode)))
1614 1615
		return 0;

1616
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1617 1618
	isec = inode->i_security;

1619
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1620 1621 1622 1623 1624
}

/* 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. */
1625
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1626 1627 1628 1629
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1630
	struct common_audit_data ad;
1631

1632
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1633
	ad.u.dentry = dentry;
1634
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646
}

/* 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;

1647
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1648
	ad.u.path = *path;
1649
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1650 1651
}

1652 1653 1654 1655 1656 1657 1658 1659 1660
/* 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;
1661
	return inode_has_perm(cred, file_inode(file), av, &ad);
1662 1663
}

L
Linus Torvalds 已提交
1664 1665 1666 1667 1668 1669 1670 1671
/* 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. */
1672 1673 1674
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1675 1676
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1677
	struct inode *inode = file_inode(file);
1678
	struct common_audit_data ad;
1679
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1680 1681
	int rc;

1682
	ad.type = LSM_AUDIT_DATA_PATH;
1683
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1684

1685 1686
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1687 1688 1689 1690
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1691
			goto out;
L
Linus Torvalds 已提交
1692 1693 1694
	}

	/* av is zero if only checking access to the descriptor. */
1695
	rc = 0;
L
Linus Torvalds 已提交
1696
	if (av)
1697
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1698

1699 1700
out:
	return rc;
L
Linus Torvalds 已提交
1701 1702 1703 1704 1705 1706 1707
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1708
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1709 1710
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1711
	u32 sid, newsid;
1712
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1713 1714 1715 1716 1717
	int rc;

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

1718 1719 1720
	sid = tsec->sid;
	newsid = tsec->create_sid;

1721
	ad.type = LSM_AUDIT_DATA_DENTRY;
1722
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1723

1724
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1725 1726 1727 1728 1729
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1730
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1731 1732
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1733 1734 1735 1736
		if (rc)
			return rc;
	}

1737
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1738 1739 1740 1741 1742 1743 1744 1745
	if (rc)
		return rc;

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

1746 1747 1748 1749
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1750
	u32 sid = task_sid(ctx);
1751

1752
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1753 1754
}

1755 1756 1757
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1758 1759 1760 1761 1762 1763 1764 1765

/* 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;
1766
	struct common_audit_data ad;
1767
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1768 1769 1770 1771 1772 1773
	u32 av;
	int rc;

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

1774
	ad.type = LSM_AUDIT_DATA_DENTRY;
1775
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1776 1777 1778

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1779
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793
	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
1794 1795
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1796 1797 1798
		return 0;
	}

1799
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1800 1801 1802 1803 1804 1805 1806 1807 1808
	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;
1809
	struct common_audit_data ad;
1810
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1811 1812 1813 1814 1815 1816 1817 1818 1819
	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;

1820
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1821

1822
	ad.u.dentry = old_dentry;
1823
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1824 1825 1826
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1827
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1828 1829 1830 1831
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1832
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1833 1834 1835 1836 1837
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1838
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1839 1840 1841
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1842
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1843 1844 1845 1846 1847
	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);
1848
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
				  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. */
1859
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1860 1861
			       struct super_block *sb,
			       u32 perms,
1862
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1863 1864
{
	struct superblock_security_struct *sbsec;
1865
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1866 1867

	sbsec = sb->s_security;
1868
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1869 1870 1871 1872 1873 1874 1875
}

/* 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
1876
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898
		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;
}

1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921
/* 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
1922
/*
1923
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1924 1925
 * open permission.
 */
1926
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1927
{
1928
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1929

1930 1931 1932
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1933 1934 1935
	return av;
}

L
Linus Torvalds 已提交
1936 1937
/* Hook functions begin here. */

1938
static int selinux_ptrace_access_check(struct task_struct *child,
1939
				     unsigned int mode)
L
Linus Torvalds 已提交
1940 1941 1942
{
	int rc;

1943
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1944 1945 1946
	if (rc)
		return rc;

1947
	if (mode & PTRACE_MODE_READ) {
1948 1949 1950
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1951 1952
	}

1953
	return current_has_perm(child, PROCESS__PTRACE);
1954 1955 1956 1957 1958 1959
}

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

1960
	rc = cap_ptrace_traceme(parent);
1961 1962 1963 1964
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1965 1966 1967
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1968
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1969 1970 1971
{
	int error;

1972
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1973 1974 1975
	if (error)
		return error;

1976
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1977 1978
}

D
David Howells 已提交
1979 1980 1981 1982
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
1983 1984 1985
{
	int error;

1986
	error = cap_capset(new, old,
D
David Howells 已提交
1987
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1988 1989 1990
	if (error)
		return error;

D
David Howells 已提交
1991
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1992 1993
}

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
/*
 * (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.
 */

2004 2005
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
2006 2007 2008
{
	int rc;

2009
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
2010 2011 2012
	if (rc)
		return rc;

2013
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
2014 2015 2016 2017
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2018
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2019 2020 2021 2022 2023 2024
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2025 2026 2027 2028 2029
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2030
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2031 2032 2033 2034
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2035
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2036 2037 2038 2039
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2040 2041 2042 2043 2044 2045
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2046 2047
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2048
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2049 2050
}

2051
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2052 2053 2054 2055
{
	int rc;

	switch (type) {
2056 2057
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2058 2059
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2060 2061 2062 2063
	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:
2064 2065
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2066 2067 2068 2069 2070
	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 */
2071 2072 2073
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085
	}
	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.
 */
2086
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2087 2088 2089
{
	int rc, cap_sys_admin = 0;

2090
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2091
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2092 2093 2094
	if (rc == 0)
		cap_sys_admin = 1;

2095
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2096 2097 2098 2099
}

/* binprm security operations */

2100
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2101
{
2102 2103
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2104
	struct inode_security_struct *isec;
2105
	struct common_audit_data ad;
A
Al Viro 已提交
2106
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2107 2108
	int rc;

2109
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2110 2111 2112
	if (rc)
		return rc;

2113 2114 2115
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2116 2117
		return 0;

2118 2119
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2120 2121 2122
	isec = inode->i_security;

	/* Default to the current task SID. */
2123 2124
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2125

2126
	/* Reset fs, key, and sock SIDs on execve. */
2127 2128 2129
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2130

2131 2132
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2133
		/* Reset exec SID on execve. */
2134
		new_tsec->exec_sid = 0;
2135 2136

		/*
2137 2138
		 * Minimize confusion: if no_new_privs or nosuid and a
		 * transition is explicitly requested, then fail the exec.
2139 2140 2141
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
2142 2143
		if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
			return -EACCES;
L
Linus Torvalds 已提交
2144 2145
	} else {
		/* Check for a default transition on this program. */
2146
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2147 2148
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2149 2150 2151 2152
		if (rc)
			return rc;
	}

2153
	ad.type = LSM_AUDIT_DATA_PATH;
2154
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2155

2156 2157
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2158
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2159

2160 2161
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2162 2163 2164 2165 2166
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2167
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2168 2169 2170 2171
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2172
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2173 2174 2175 2176
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194
		/* 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();
2195
			tracer = ptrace_parent(current);
2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209
			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
2210

2211 2212
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2213 2214 2215 2216 2217
	}

	return 0;
}

2218
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2219
{
2220
	const struct task_security_struct *tsec = current_security();
2221
	u32 sid, osid;
L
Linus Torvalds 已提交
2222 2223
	int atsecure = 0;

2224 2225 2226 2227
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2228 2229 2230
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2231
		atsecure = avc_has_perm(osid, sid,
2232 2233
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2234 2235
	}

2236
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2237 2238
}

A
Al Viro 已提交
2239 2240 2241 2242 2243
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
2244
/* Derived from fs/exec.c:flush_old_files. */
2245 2246
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2247 2248
{
	struct file *file, *devnull = NULL;
2249
	struct tty_struct *tty;
2250
	int drop_tty = 0;
A
Al Viro 已提交
2251
	unsigned n;
L
Linus Torvalds 已提交
2252

2253
	tty = get_current_tty();
L
Linus Torvalds 已提交
2254
	if (tty) {
N
Nick Piggin 已提交
2255
		spin_lock(&tty_files_lock);
2256
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2257
			struct tty_file_private *file_priv;
2258

L
Linus Torvalds 已提交
2259
			/* Revalidate access to controlling tty.
2260 2261 2262 2263
			   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
2264 2265 2266
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2267
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2268
				drop_tty = 1;
L
Linus Torvalds 已提交
2269
		}
N
Nick Piggin 已提交
2270
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2271
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2272
	}
2273 2274 2275
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2276 2277

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2278 2279 2280
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2281

A
Al Viro 已提交
2282
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2283 2284 2285 2286 2287 2288 2289
	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
2290
		fput(devnull);
L
Linus Torvalds 已提交
2291 2292
}

2293 2294 2295 2296
/*
 * 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
2297
{
2298 2299 2300
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2301

2302 2303 2304
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2305

2306 2307
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2308

2309 2310
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2311

2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
	/* 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) {
2325 2326
		/* protect against do_prlimit() */
		task_lock(current);
2327 2328 2329 2330
		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
2331
		}
2332 2333
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2334 2335 2336 2337
	}
}

/*
2338 2339
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2340
 */
2341
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2342
{
2343
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2344
	struct itimerval itimer;
2345
	u32 osid, sid;
L
Linus Torvalds 已提交
2346 2347
	int rc, i;

2348 2349 2350 2351
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2352 2353
		return;

2354 2355 2356 2357 2358 2359 2360 2361
	/* 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
2362 2363 2364 2365 2366
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2367 2368 2369 2370 2371
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2372 2373 2374
		spin_unlock_irq(&current->sighand->siglock);
	}

2375 2376
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2377
	read_lock(&tasklist_lock);
2378
	__wake_up_parent(current, current->real_parent);
2379
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403
}

/* 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)
{
2404 2405 2406
	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) ||
2407 2408
		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
2409 2410 2411 2412 2413 2414 2415
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2416
	} else
L
Linus Torvalds 已提交
2417 2418 2419 2420 2421
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2422 2423
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2424 2425 2426 2427 2428 2429
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2430
	} else
2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442
		*first = 0;

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

2443
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2444 2445 2446 2447
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2448
	int open_quote = 0;
L
Linus Torvalds 已提交
2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463

	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 {
2464 2465 2466 2467
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2468 2469 2470
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2471
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2472 2473 2474 2475 2476 2477 2478
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2479
	strcpy(in_save, nosec_save);
2480
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2481 2482 2483 2484
out:
	return rc;
}

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 2518 2519
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;

2520
		if (flags[i] == SBLABEL_MNT)
2521 2522
			continue;
		len = strlen(mount_options[i]);
2523 2524
		rc = security_context_to_sid(mount_options[i], len, &sid,
					     GFP_KERNEL);
2525 2526
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2527 2528
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565
			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 "
2566 2567
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2568 2569 2570
	goto out_free_opts;
}

2571
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2572
{
2573
	const struct cred *cred = current_cred();
2574
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2575 2576 2577 2578 2579 2580
	int rc;

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

2581 2582 2583 2584
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2585
	ad.type = LSM_AUDIT_DATA_DENTRY;
2586
	ad.u.dentry = sb->s_root;
2587
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2588 2589
}

2590
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2591
{
2592
	const struct cred *cred = current_cred();
2593
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2594

2595
	ad.type = LSM_AUDIT_DATA_DENTRY;
2596
	ad.u.dentry = dentry->d_sb->s_root;
2597
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2598 2599
}

A
Al Viro 已提交
2600
static int selinux_mount(const char *dev_name,
2601
			 struct path *path,
A
Al Viro 已提交
2602
			 const char *type,
2603 2604
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2605
{
2606
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2607 2608

	if (flags & MS_REMOUNT)
2609
		return superblock_has_perm(cred, path->dentry->d_sb,
2610
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2611
	else
E
Eric Paris 已提交
2612
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2613 2614 2615 2616
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2617
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2618

2619
	return superblock_has_perm(cred, mnt->mnt_sb,
2620
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634
}

/* 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);
}

2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668
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);
}

2669
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2670 2671
				       const struct qstr *qstr,
				       const char **name,
2672
				       void **value, size_t *len)
2673
{
2674
	const struct task_security_struct *tsec = current_security();
2675 2676
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2677
	u32 sid, newsid, clen;
2678
	int rc;
2679
	char *context;
2680 2681 2682 2683

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

2684 2685 2686
	sid = tsec->sid;
	newsid = tsec->create_sid;

2687 2688 2689
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2690
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2691
		rc = security_transition_sid(sid, dsec->sid,
2692
					     inode_mode_to_security_class(inode->i_mode),
2693
					     qstr, &newsid);
2694 2695 2696 2697
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2698
			       __func__,
2699 2700 2701 2702 2703
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2704
	/* Possibly defer initialization to selinux_complete_init. */
2705
	if (sbsec->flags & SE_SBINITIALIZED) {
2706 2707 2708 2709 2710
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2711

2712
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2713 2714
		return -EOPNOTSUPP;

2715 2716
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2717

2718
	if (value && len) {
2719
		rc = security_sid_to_context_force(newsid, &context, &clen);
2720
		if (rc)
2721 2722 2723
			return rc;
		*value = context;
		*len = clen;
2724 2725 2726 2727 2728
	}

	return 0;
}

A
Al Viro 已提交
2729
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748
{
	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);
}

2749
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2750 2751 2752 2753 2754 2755 2756 2757 2758
{
	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
2759
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2760 2761 2762 2763 2764
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2765
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2766 2767 2768 2769 2770 2771
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2772 2773
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2774
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2775 2776 2777 2778
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2779
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2780

E
Eric Paris 已提交
2781
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2782 2783
}

2784 2785
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
2786
					   int result,
2787
					   unsigned flags)
L
Linus Torvalds 已提交
2788
{
2789
	struct common_audit_data ad;
2790 2791 2792
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2793
	ad.type = LSM_AUDIT_DATA_INODE;
2794 2795 2796
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2797
			    audited, denied, result, &ad, flags);
2798 2799 2800 2801 2802
	if (rc)
		return rc;
	return 0;
}

2803
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2804
{
2805
	const struct cred *cred = current_cred();
2806 2807
	u32 perms;
	bool from_access;
2808
	unsigned flags = mask & MAY_NOT_BLOCK;
2809 2810 2811 2812 2813
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2814

2815
	from_access = mask & MAY_ACCESS;
2816 2817
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2818 2819
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2820 2821
		return 0;

2822
	validate_creds(cred);
2823

2824 2825
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2826 2827 2828

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

2829 2830 2831 2832 2833 2834 2835 2836 2837 2838
	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;

2839
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
2840 2841 2842
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2843 2844 2845 2846
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2847
	const struct cred *cred = current_cred();
2848
	unsigned int ia_valid = iattr->ia_valid;
2849
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2850

2851 2852 2853 2854 2855 2856 2857
	/* 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
2858

2859 2860
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2861
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2862

2863
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2864 2865 2866
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2867 2868 2869 2870
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2871
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2872 2873 2874 2875
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2876

E
Eric Paris 已提交
2877
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2878 2879
}

2880
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2881
{
2882 2883
	const struct cred *cred = current_cred();

2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897
	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
2898
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2899 2900
}

2901 2902
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
2903 2904 2905 2906
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2907
	struct common_audit_data ad;
2908
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2909 2910
	int rc = 0;

2911 2912
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2913 2914

	sbsec = inode->i_sb->s_security;
2915
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2916 2917
		return -EOPNOTSUPP;

2918
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2919 2920
		return -EPERM;

2921
	ad.type = LSM_AUDIT_DATA_DENTRY;
2922
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2923

2924
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2925 2926 2927 2928
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

2929
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2930
	if (rc == -EINVAL) {
2931 2932 2933 2934 2935 2936 2937
		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 */
2938 2939 2940 2941 2942 2943 2944 2945 2946 2947
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2948 2949 2950 2951 2952
			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);

2953
			return rc;
2954
		}
2955 2956
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2957 2958 2959
	if (rc)
		return rc;

2960
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2961 2962 2963 2964
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2965
	rc = security_validate_transition(isec->sid, newsid, sid,
2966
					  isec->sclass);
L
Linus Torvalds 已提交
2967 2968 2969 2970 2971 2972 2973 2974 2975 2976
	if (rc)
		return rc;

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

2977
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2978
					const void *value, size_t size,
2979
					int flags)
L
Linus Torvalds 已提交
2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990
{
	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;
	}

2991
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2992
	if (rc) {
2993 2994 2995
		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
2996 2997 2998
		return;
	}

2999
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3000
	isec->sid = newsid;
3001 3002
	isec->initialized = 1;

L
Linus Torvalds 已提交
3003 3004 3005
	return;
}

3006
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3007
{
3008 3009
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3010
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3011 3012
}

3013
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3014
{
3015 3016
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3017
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3018 3019
}

3020
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3021
{
3022 3023
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
3024 3025 3026 3027 3028 3029

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

3030
/*
3031
 * Copy the inode security context value to the user.
3032 3033 3034
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3035
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3036
{
3037 3038 3039
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
3040
	struct inode_security_struct *isec = inode->i_security;
3041

3042 3043
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3044

3045 3046 3047 3048 3049 3050 3051 3052 3053
	/*
	 * 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.
	 */
3054
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3055
				SECURITY_CAP_NOAUDIT);
3056 3057 3058 3059 3060
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3061 3062 3063 3064 3065 3066 3067 3068 3069 3070
	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
3071 3072 3073
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3074
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085
{
	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;

3086
	rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3087 3088 3089
	if (rc)
		return rc;

3090
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3091
	isec->sid = newsid;
3092
	isec->initialized = 1;
L
Linus Torvalds 已提交
3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103
	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;
}

3104 3105 3106 3107 3108 3109
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
3110 3111
/* file security operations */

3112
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3113
{
3114
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3115
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3116 3117 3118 3119 3120

	/* 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;

3121 3122
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3123 3124
}

3125 3126
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3127
	struct inode *inode = file_inode(file);
3128 3129 3130 3131
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3132
	if (!mask)
3133 3134 3135
		/* No permission to check.  Existence test. */
		return 0;

3136 3137
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3138
		/* No change since file_open check. */
3139 3140
		return 0;

3141 3142 3143
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156
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)
{
3157
	const struct cred *cred = current_cred();
3158
	int error = 0;
L
Linus Torvalds 已提交
3159

3160 3161 3162 3163 3164 3165 3166
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3167
	case FS_IOC_GETFLAGS:
3168
	/* fall through */
3169
	case FS_IOC_GETVERSION:
3170 3171
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3172

3173
	case FS_IOC_SETFLAGS:
3174
	/* fall through */
3175
	case FS_IOC_SETVERSION:
3176 3177 3178 3179 3180 3181 3182 3183 3184
		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
3185

3186 3187
	case KDSKBENT:
	case KDSKBSENT:
3188 3189
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3190 3191 3192 3193 3194 3195 3196 3197 3198
		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
3199 3200
}

3201 3202
static int default_noexec;

L
Linus Torvalds 已提交
3203 3204
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3205
	const struct cred *cred = current_cred();
D
David Howells 已提交
3206
	int rc = 0;
3207

3208 3209
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3210 3211 3212 3213 3214
		/*
		 * 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
3215
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3216
		if (rc)
D
David Howells 已提交
3217
			goto error;
L
Linus Torvalds 已提交
3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230
	}

	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;

3231
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3232
	}
D
David Howells 已提交
3233 3234 3235

error:
	return rc;
L
Linus Torvalds 已提交
3236 3237
}

3238
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3239
{
3240 3241 3242 3243 3244 3245
	int rc;

	/* do DAC check on address space usage */
	rc = cap_mmap_addr(addr);
	if (rc)
		return rc;
L
Linus Torvalds 已提交
3246

3247
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3248
		u32 sid = current_sid();
3249 3250
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3251 3252
	}

3253
	return rc;
3254
}
L
Linus Torvalds 已提交
3255

3256 3257 3258
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269
	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)
{
3270
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3271 3272 3273 3274

	if (selinux_checkreqprot)
		prot = reqprot;

3275 3276
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3277
		int rc = 0;
3278 3279
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3280
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3281 3282 3283
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3284
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3285 3286 3287 3288 3289 3290 3291 3292
		} 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
3293
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3294
		}
3295 3296 3297
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3298 3299 3300 3301 3302 3303

	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)
{
3304 3305 3306
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3307 3308 3309 3310 3311
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3312
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3313 3314 3315
	int err = 0;

	switch (cmd) {
3316 3317
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3318
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3319
			break;
3320 3321 3322 3323 3324 3325 3326
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3327
	case F_GETOWNER_UIDS:
3328
		/* Just check FD__USE permission */
3329
		err = file_has_perm(cred, file, 0);
3330 3331 3332 3333
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3334 3335 3336
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3337
#if BITS_PER_LONG == 32
3338 3339 3340
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3341
#endif
3342
		err = file_has_perm(cred, file, FILE__LOCK);
3343
		break;
L
Linus Torvalds 已提交
3344 3345 3346 3347 3348 3349 3350 3351 3352 3353
	}

	return err;
}

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

	fsec = file->f_security;
3354
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3355 3356 3357 3358 3359 3360 3361

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3362
	struct file *file;
3363
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3364 3365 3366 3367
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3368
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3369 3370 3371 3372 3373 3374 3375 3376

	fsec = file->f_security;

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

3377
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3378 3379 3380 3381 3382
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3383 3384 3385
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3386 3387
}

3388
static int selinux_file_open(struct file *file, const struct cred *cred)
3389 3390 3391
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3392

3393
	fsec = file->f_security;
A
Al Viro 已提交
3394
	isec = file_inode(file)->i_security;
3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411
	/*
	 * 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.
	 */
3412
	return file_path_has_perm(cred, file, open_file_to_av(file));
3413 3414
}

L
Linus Torvalds 已提交
3415 3416 3417 3418
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3419
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3420 3421
}

3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436
/*
 * 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
3437 3438 3439 3440
/*
 * 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
3441
{
D
David Howells 已提交
3442
	struct task_security_struct *tsec = cred->security;
3443

3444 3445 3446 3447 3448
	/*
	 * 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);
3449
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3450 3451
	kfree(tsec);
}
L
Linus Torvalds 已提交
3452

D
David Howells 已提交
3453 3454 3455 3456 3457 3458 3459 3460
/*
 * 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
3461

D
David Howells 已提交
3462
	old_tsec = old->security;
L
Linus Torvalds 已提交
3463

D
David Howells 已提交
3464 3465 3466
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3467

D
David Howells 已提交
3468
	new->security = tsec;
L
Linus Torvalds 已提交
3469 3470 3471
	return 0;
}

3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482
/*
 * 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;
}

3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523
/*
 * 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;
3524
	return ret;
3525 3526
}

3527
static int selinux_kernel_module_request(char *kmod_name)
3528
{
3529 3530 3531 3532 3533
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3534
	ad.type = LSM_AUDIT_DATA_KMOD;
3535 3536 3537 3538
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3539 3540
}

L
Linus Torvalds 已提交
3541 3542
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3543
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3544 3545 3546 3547
}

static int selinux_task_getpgid(struct task_struct *p)
{
3548
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3549 3550 3551 3552
}

static int selinux_task_getsid(struct task_struct *p)
{
3553
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3554 3555
}

3556 3557
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3558
	*secid = task_sid(p);
3559 3560
}

L
Linus Torvalds 已提交
3561 3562 3563 3564
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3565
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3566 3567 3568
	if (rc)
		return rc;

3569
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3570 3571
}

3572 3573
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3574 3575
	int rc;

3576
	rc = cap_task_setioprio(p, ioprio);
3577 3578 3579
	if (rc)
		return rc;

3580
	return current_has_perm(p, PROCESS__SETSCHED);
3581 3582
}

3583 3584
static int selinux_task_getioprio(struct task_struct *p)
{
3585
	return current_has_perm(p, PROCESS__GETSCHED);
3586 3587
}

3588 3589
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3590
{
3591
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3592 3593 3594 3595

	/* 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
3596
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3597
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3598
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3599 3600 3601 3602

	return 0;
}

3603
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3604
{
3605 3606
	int rc;

3607
	rc = cap_task_setscheduler(p);
3608 3609 3610
	if (rc)
		return rc;

3611
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3612 3613 3614 3615
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3616
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3617 3618
}

3619 3620
static int selinux_task_movememory(struct task_struct *p)
{
3621
	return current_has_perm(p, PROCESS__SETSCHED);
3622 3623
}

3624 3625
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3626 3627 3628 3629 3630 3631 3632 3633
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3634
	if (secid)
3635 3636
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3637
	else
3638
		rc = current_has_perm(p, perm);
3639
	return rc;
L
Linus Torvalds 已提交
3640 3641 3642 3643
}

static int selinux_task_wait(struct task_struct *p)
{
3644
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3645 3646 3647 3648 3649 3650
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3651
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3652

3653
	isec->sid = sid;
L
Linus Torvalds 已提交
3654 3655 3656 3657
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3658
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3659
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3660 3661 3662 3663
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3664
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3665 3666 3667 3668 3669 3670 3671 3672
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3673 3674
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3675 3676
	ret = 0;

3677 3678 3679
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3680
	switch (ih->protocol) {
3681 3682
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3683

3684 3685
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3686 3687 3688 3689 3690 3691

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

3692 3693
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3694
		break;
3695 3696 3697 3698 3699 3700 3701 3702
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3703
		offset += ihlen;
3704
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3705
		if (uh == NULL)
3706
			break;
L
Linus Torvalds 已提交
3707

3708 3709
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3710 3711
		break;
	}
L
Linus Torvalds 已提交
3712

J
James Morris 已提交
3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723
	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;

3724 3725
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3726
		break;
3727
	}
J
James Morris 已提交
3728

3729 3730 3731
	default:
		break;
	}
L
Linus Torvalds 已提交
3732 3733 3734 3735 3736 3737 3738
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3739
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3740
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3741 3742 3743 3744
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3745
	__be16 frag_off;
L
Linus Torvalds 已提交
3746

3747
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3748 3749 3750 3751
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3752 3753
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3754 3755 3756 3757
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3758
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3759 3760 3761
	if (offset < 0)
		goto out;

3762 3763 3764
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3765 3766
	switch (nexthdr) {
	case IPPROTO_TCP: {
3767
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3768 3769 3770 3771 3772

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

3773 3774
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3775 3776 3777 3778 3779 3780 3781 3782 3783 3784
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3785 3786
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3787 3788 3789
		break;
	}

J
James Morris 已提交
3790 3791 3792 3793 3794 3795 3796
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3797 3798
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3799
		break;
3800
	}
J
James Morris 已提交
3801

L
Linus Torvalds 已提交
3802 3803 3804 3805 3806 3807 3808 3809 3810 3811
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3812
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3813
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3814
{
3815 3816
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3817

3818
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3819
	case PF_INET:
3820
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3821 3822
		if (ret)
			goto parse_error;
3823 3824
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3825
		goto okay;
L
Linus Torvalds 已提交
3826 3827 3828

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3829
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3830 3831
		if (ret)
			goto parse_error;
3832 3833
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3834
		goto okay;
L
Linus Torvalds 已提交
3835 3836
#endif	/* IPV6 */
	default:
3837 3838
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3839 3840
	}

3841 3842 3843 3844
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3845
	return ret;
3846 3847 3848 3849 3850

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3851 3852
}

3853
/**
3854
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3855
 * @skb: the packet
3856
 * @family: protocol family
3857
 * @sid: the packet's peer label SID
3858 3859
 *
 * Description:
3860 3861 3862 3863 3864 3865
 * 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.
3866 3867
 *
 */
3868
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3869
{
3870
	int err;
3871 3872
	u32 xfrm_sid;
	u32 nlbl_sid;
3873
	u32 nlbl_type;
3874

3875
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3876 3877 3878 3879 3880
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3881

3882 3883 3884 3885 3886
	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");
3887
		return -EACCES;
3888
	}
3889 3890

	return 0;
3891 3892
}

3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916
/**
 * 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
3917
/* socket security operations */
3918

3919 3920
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3921
{
3922 3923 3924 3925 3926 3927 3928
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3929 3930
}

3931
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3932
{
3933
	struct sk_security_struct *sksec = sk->sk_security;
3934
	struct common_audit_data ad;
3935
	struct lsm_network_audit net = {0,};
3936
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3937

3938 3939
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3940

3941
	ad.type = LSM_AUDIT_DATA_NET;
3942 3943
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3944

3945
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3946 3947 3948 3949 3950
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3951
	const struct task_security_struct *tsec = current_security();
3952
	u32 newsid;
3953
	u16 secclass;
3954
	int rc;
L
Linus Torvalds 已提交
3955 3956

	if (kern)
3957
		return 0;
3958 3959

	secclass = socket_type_to_security_class(family, type, protocol);
3960 3961 3962 3963
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3964
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3965 3966
}

V
Venkat Yekkirala 已提交
3967 3968
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3969
{
3970
	const struct task_security_struct *tsec = current_security();
3971
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3972
	struct sk_security_struct *sksec;
3973 3974
	int err = 0;

3975 3976
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3977 3978
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3979 3980 3981 3982 3983
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3984

L
Linus Torvalds 已提交
3985 3986
	isec->initialized = 1;

3987 3988 3989
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3990
		sksec->sclass = isec->sclass;
3991
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3992 3993
	}

V
Venkat Yekkirala 已提交
3994
	return err;
L
Linus Torvalds 已提交
3995 3996 3997 3998 3999 4000 4001 4002
}

/* 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)
{
4003
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
4004 4005 4006
	u16 family;
	int err;

4007
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
4008 4009 4010 4011 4012
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4013 4014
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4015
	 */
4016
	family = sk->sk_family;
L
Linus Torvalds 已提交
4017 4018
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4019
		struct sk_security_struct *sksec = sk->sk_security;
4020
		struct common_audit_data ad;
4021
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4022 4023 4024
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4025
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036

		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;
		}

4037 4038 4039
		if (snum) {
			int low, high;

4040
			inet_get_local_port_range(sock_net(sk), &low, &high);
4041 4042

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
4043 4044
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4045 4046
				if (err)
					goto out;
4047
				ad.type = LSM_AUDIT_DATA_NET;
4048 4049 4050
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4051 4052
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4053 4054 4055 4056
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4057
		}
4058

4059
		switch (sksec->sclass) {
4060
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4061 4062
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4063

4064
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4065 4066
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4067 4068 4069 4070 4071

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4072 4073 4074 4075
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4076

4077
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4078 4079
		if (err)
			goto out;
4080

4081
		ad.type = LSM_AUDIT_DATA_NET;
4082 4083 4084
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4085 4086

		if (family == PF_INET)
4087
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4088
		else
4089
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4090

4091 4092
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4093 4094 4095 4096 4097 4098 4099 4100 4101
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4102
	struct sock *sk = sock->sk;
4103
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4104 4105
	int err;

4106
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4107 4108 4109 4110
	if (err)
		return err;

	/*
J
James Morris 已提交
4111
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4112
	 */
4113 4114
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4115
		struct common_audit_data ad;
4116
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4117 4118 4119
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4120
		u32 sid, perm;
L
Linus Torvalds 已提交
4121 4122 4123

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4124
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4125 4126 4127 4128
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4129
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4130 4131 4132 4133
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4134
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4135 4136 4137
		if (err)
			goto out;

4138
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4139 4140
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4141
		ad.type = LSM_AUDIT_DATA_NET;
4142 4143 4144
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4145
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4146 4147 4148 4149
		if (err)
			goto out;
	}

4150 4151
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4152 4153 4154 4155 4156 4157
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4158
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4159 4160 4161 4162 4163 4164 4165 4166
}

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

4167
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181
	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,
4182
				  int size)
L
Linus Torvalds 已提交
4183
{
4184
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4185 4186 4187 4188 4189
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4190
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4191 4192 4193 4194
}

static int selinux_socket_getsockname(struct socket *sock)
{
4195
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4196 4197 4198 4199
}

static int selinux_socket_getpeername(struct socket *sock)
{
4200
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4201 4202
}

4203
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4204
{
4205 4206
	int err;

4207
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4208 4209 4210 4211
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4212 4213 4214 4215 4216
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4217
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4218 4219 4220 4221
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4222
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4223 4224
}

4225 4226
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4227 4228
					      struct sock *newsk)
{
4229 4230
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4231
	struct sk_security_struct *sksec_new = newsk->sk_security;
4232
	struct common_audit_data ad;
4233
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4234 4235
	int err;

4236
	ad.type = LSM_AUDIT_DATA_NET;
4237 4238
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4239

4240 4241
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4242 4243 4244 4245 4246
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4247 4248 4249 4250 4251
	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;
4252

4253 4254 4255 4256
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4257 4258 4259 4260 4261
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4262 4263
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4264
	struct common_audit_data ad;
4265
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4266

4267
	ad.type = LSM_AUDIT_DATA_NET;
4268 4269
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4270

4271 4272
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4273 4274
}

4275 4276
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4277
				    struct common_audit_data *ad)
4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297
{
	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);
}

4298
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4299
				       u16 family)
4300
{
4301
	int err = 0;
4302 4303
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4304
	struct common_audit_data ad;
4305
	struct lsm_network_audit net = {0,};
4306 4307
	char *addrp;

4308
	ad.type = LSM_AUDIT_DATA_NET;
4309 4310 4311
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4312 4313 4314
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4315

4316
	if (selinux_secmark_enabled()) {
4317
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4318
				   PACKET__RECV, &ad);
4319 4320 4321
		if (err)
			return err;
	}
4322

4323 4324 4325 4326
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4327

4328 4329 4330 4331 4332
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4333
	int err;
4334
	struct sk_security_struct *sksec = sk->sk_security;
4335 4336
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4337
	struct common_audit_data ad;
4338
	struct lsm_network_audit net = {0,};
4339
	char *addrp;
4340 4341
	u8 secmark_active;
	u8 peerlbl_active;
4342 4343

	if (family != PF_INET && family != PF_INET6)
4344
		return 0;
4345 4346

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4347
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4348 4349
		family = PF_INET;

4350 4351 4352 4353
	/* 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. */
4354
	if (!selinux_policycap_netpeer)
4355 4356 4357
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4358
	peerlbl_active = selinux_peerlbl_enabled();
4359 4360 4361
	if (!secmark_active && !peerlbl_active)
		return 0;

4362
	ad.type = LSM_AUDIT_DATA_NET;
4363 4364 4365
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4366
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4367
	if (err)
4368
		return err;
4369

4370
	if (peerlbl_active) {
4371 4372 4373
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4374 4375
		if (err)
			return err;
4376
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4377
					       peer_sid, &ad);
4378 4379
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4380
			return err;
4381
		}
4382 4383
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4384
		if (err) {
4385
			selinux_netlbl_err(skb, err, 0);
C
Chad Hanson 已提交
4386 4387
			return err;
		}
4388 4389
	}

4390
	if (secmark_active) {
4391 4392 4393 4394 4395 4396
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4397
	return err;
L
Linus Torvalds 已提交
4398 4399
}

C
Catherine Zhang 已提交
4400 4401
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4402 4403 4404 4405
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4406
	struct sk_security_struct *sksec = sock->sk->sk_security;
4407
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4408

4409 4410
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4411
		peer_sid = sksec->peer_sid;
4412 4413
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4414

C
Catherine Zhang 已提交
4415
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4416
	if (err)
4417
		return err;
L
Linus Torvalds 已提交
4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433

	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;
}

4434
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4435
{
4436
	u32 peer_secid = SECSID_NULL;
4437
	u16 family;
C
Catherine Zhang 已提交
4438

4439 4440 4441 4442 4443
	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)
4444 4445 4446 4447 4448
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4449
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4450
	else if (skb)
4451
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4452

4453
out:
4454
	*secid = peer_secid;
4455 4456 4457
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4458 4459
}

A
Al Viro 已提交
4460
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4461
{
4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473
	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
4474 4475 4476 4477
}

static void selinux_sk_free_security(struct sock *sk)
{
4478 4479 4480 4481 4482
	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
4483 4484
}

4485
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4486
{
4487 4488
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4489

4490 4491 4492
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4493

4494
	selinux_netlbl_sk_security_reset(newsksec);
4495 4496
}

V
Venkat Yekkirala 已提交
4497
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4498
{
4499
	if (!sk)
V
Venkat Yekkirala 已提交
4500
		*secid = SECINITSID_ANY_SOCKET;
4501 4502
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4503

V
Venkat Yekkirala 已提交
4504
		*secid = sksec->sid;
4505
	}
4506 4507
}

4508
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4509 4510 4511 4512
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4513 4514
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
4515
		isec->sid = sksec->sid;
4516
	sksec->sclass = isec->sclass;
4517 4518
}

4519 4520
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4521 4522 4523
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4524
	u16 family = req->rsk_ops->family;
4525
	u32 connsid;
4526 4527
	u32 peersid;

4528
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4529 4530
	if (err)
		return err;
4531 4532 4533 4534 4535
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4536

4537
	return selinux_netlbl_inet_conn_request(req, family);
4538 4539
}

4540 4541
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4542 4543 4544 4545
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4546
	newsksec->peer_sid = req->peer_secid;
4547 4548 4549 4550
	/* 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. */
4551

P
Paul Moore 已提交
4552 4553
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4554
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4555 4556
}

4557
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4558
{
4559
	u16 family = sk->sk_family;
4560 4561
	struct sk_security_struct *sksec = sk->sk_security;

4562 4563 4564 4565 4566
	/* 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);
4567 4568
}

4569 4570 4571 4572 4573
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594
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);
}

4595 4596
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4597
{
4598
	fl->flowi_secid = req->secid;
4599 4600
}

4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618
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);
}

4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633
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);
}

4634
static int selinux_tun_dev_attach_queue(void *security)
4635
{
4636 4637 4638 4639 4640 4641 4642 4643 4644
	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;
4645 4646 4647 4648 4649 4650 4651 4652 4653
	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 */

4654
	sksec->sid = tunsec->sid;
4655
	sksec->sclass = SECCLASS_TUN_SOCKET;
4656 4657

	return 0;
4658 4659
}

4660
static int selinux_tun_dev_open(void *security)
4661
{
4662
	struct tun_security_struct *tunsec = security;
4663 4664 4665
	u32 sid = current_sid();
	int err;

4666
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4667 4668 4669 4670 4671 4672 4673
			   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;
4674
	tunsec->sid = sid;
4675 4676 4677 4678

	return 0;
}

L
Linus Torvalds 已提交
4679 4680 4681 4682 4683
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4684
	struct sk_security_struct *sksec = sk->sk_security;
4685

4686
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4687 4688 4689
		err = -EINVAL;
		goto out;
	}
4690
	nlh = nlmsg_hdr(skb);
4691

4692
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4693 4694
	if (err) {
		if (err == -EINVAL) {
4695
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4696 4697
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4698
				  nlh->nlmsg_type, sksec->sclass);
4699
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4700 4701 4702 4703 4704 4705 4706 4707 4708
				err = 0;
		}

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

4709
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4710 4711 4712 4713 4714 4715
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4716 4717
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4718
{
4719
	int err;
4720 4721
	char *addrp;
	u32 peer_sid;
4722
	struct common_audit_data ad;
4723
	struct lsm_network_audit net = {0,};
4724
	u8 secmark_active;
4725
	u8 netlbl_active;
4726
	u8 peerlbl_active;
4727

4728 4729
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4730

4731
	secmark_active = selinux_secmark_enabled();
4732
	netlbl_active = netlbl_enabled();
4733
	peerlbl_active = selinux_peerlbl_enabled();
4734 4735
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4736

4737 4738 4739
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4740
	ad.type = LSM_AUDIT_DATA_NET;
4741 4742 4743
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4744 4745 4746
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4747 4748 4749 4750 4751
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4752
			return NF_DROP;
4753 4754
		}
	}
4755 4756 4757 4758 4759 4760

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

4761 4762 4763 4764 4765 4766 4767 4768
	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;

4769 4770 4771
	return NF_ACCEPT;
}

4772
static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4773 4774 4775 4776 4777 4778 4779 4780 4781
					 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)
4782
static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4783 4784 4785 4786 4787 4788 4789 4790 4791
					 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 */

4792 4793 4794
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4795
	struct sock *sk;
4796 4797 4798 4799 4800 4801 4802 4803
	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 */
4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824
	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;
4825 4826 4827 4828 4829 4830 4831 4832 4833
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

4834
static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4835 4836 4837 4838 4839 4840 4841 4842
					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);
}

4843 4844
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4845
						u16 family)
4846 4847 4848
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4849
	struct common_audit_data ad;
4850
	struct lsm_network_audit net = {0,};
4851 4852
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4853

4854 4855 4856 4857
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4858
	ad.type = LSM_AUDIT_DATA_NET;
4859 4860 4861
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4862 4863 4864
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4865
	if (selinux_secmark_enabled())
4866
		if (avc_has_perm(sksec->sid, skb->secmark,
4867
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4868
			return NF_DROP_ERR(-ECONNREFUSED);
4869

4870 4871
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4872 4873

	return NF_ACCEPT;
4874 4875
}

4876 4877
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4878
{
4879 4880
	u32 secmark_perm;
	u32 peer_sid;
4881
	struct sock *sk;
4882
	struct common_audit_data ad;
4883
	struct lsm_network_audit net = {0,};
4884 4885 4886
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4887

4888 4889 4890 4891
	/* 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. */
4892
	if (!selinux_policycap_netpeer)
4893
		return selinux_ip_postroute_compat(skb, ifindex, family);
4894 4895 4896 4897 4898 4899 4900 4901

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

	sk = skb->sk;

4902
#ifdef CONFIG_XFRM
4903 4904 4905 4906 4907
	/* 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
4908 4909 4910 4911 4912 4913 4914 4915
	 *       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))
4916
		return NF_ACCEPT;
4917
#endif
4918

4919
	if (sk == NULL) {
4920 4921 4922 4923
		/* 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. */
4924 4925
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4926
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4927
				return NF_DROP;
4928 4929
		} else {
			secmark_perm = PACKET__SEND;
4930
			peer_sid = SECINITSID_KERNEL;
4931
		}
4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945
	} 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;
4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964
		/* 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);
			}
		}
4965 4966 4967
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4968
	} else {
4969 4970
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4971 4972 4973 4974
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4975

4976
	ad.type = LSM_AUDIT_DATA_NET;
4977 4978 4979
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4980
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4981
		return NF_DROP;
4982

4983 4984 4985
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4986
			return NF_DROP_ERR(-ECONNREFUSED);
4987 4988 4989 4990 4991 4992

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4993
			return NF_DROP;
4994 4995
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4996
			return NF_DROP_ERR(-ECONNREFUSED);
4997 4998

		if (sel_netnode_sid(addrp, family, &node_sid))
4999
			return NF_DROP;
5000 5001
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
5002
			return NF_DROP_ERR(-ECONNREFUSED);
5003
	}
5004

5005
	return NF_ACCEPT;
L
Linus Torvalds 已提交
5006 5007
}

5008
static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
5009 5010 5011 5012
					   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
5013
{
5014
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
5015 5016 5017
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5018
static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5019 5020 5021 5022
					   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
5023
{
5024
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
5025 5026 5027 5028 5029 5030 5031 5032 5033
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

5034
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
5035 5036 5037
	if (err)
		return err;

5038
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5039 5040 5041 5042 5043 5044 5045
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
5046
	u32 sid;
L
Linus Torvalds 已提交
5047

J
James Morris 已提交
5048
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5049 5050 5051
	if (!isec)
		return -ENOMEM;

5052
	sid = task_sid(task);
L
Linus Torvalds 已提交
5053
	isec->sclass = sclass;
5054
	isec->sid = sid;
L
Linus Torvalds 已提交
5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070
	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
5071
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089
	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,
5090
			u32 perms)
L
Linus Torvalds 已提交
5091 5092
{
	struct ipc_security_struct *isec;
5093
	struct common_audit_data ad;
5094
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5095 5096 5097

	isec = ipc_perms->security;

5098
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5099 5100
	ad.u.ipc_id = ipc_perms->key;

5101
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117
}

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;
5118
	struct common_audit_data ad;
5119
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5120 5121 5122 5123 5124 5125 5126 5127
	int rc;

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

	isec = msq->q_perm.security;

5128
	ad.type = LSM_AUDIT_DATA_IPC;
5129
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5130

5131
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147
			  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;
5148
	struct common_audit_data ad;
5149
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5150 5151 5152

	isec = msq->q_perm.security;

5153
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5154 5155
	ad.u.ipc_id = msq->q_perm.key;

5156
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5157 5158 5159 5160 5161 5162 5163 5164
			    MSGQ__ASSOCIATE, &ad);
}

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

5165
	switch (cmd) {
L
Linus Torvalds 已提交
5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183
	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;
	}

5184
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5185 5186 5187 5188 5189 5190 5191
	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;
5192
	struct common_audit_data ad;
5193
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206
	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
		 */
5207
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5208
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5209 5210 5211 5212
		if (rc)
			return rc;
	}

5213
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5214 5215 5216
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5217
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5218 5219 5220
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5221 5222
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5223 5224
	if (!rc)
		/* Can the message be put in the queue? */
5225 5226
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5227 5228 5229 5230 5231 5232 5233 5234 5235 5236

	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;
5237
	struct common_audit_data ad;
5238
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5239 5240 5241 5242 5243
	int rc;

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

5244
	ad.type = LSM_AUDIT_DATA_IPC;
5245
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5246

5247
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5248 5249
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5250
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5251 5252 5253 5254 5255 5256 5257 5258
				  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;
5259
	struct common_audit_data ad;
5260
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5261 5262 5263 5264 5265 5266 5267 5268
	int rc;

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

	isec = shp->shm_perm.security;

5269
	ad.type = LSM_AUDIT_DATA_IPC;
5270
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5271

5272
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288
			  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;
5289
	struct common_audit_data ad;
5290
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5291 5292 5293

	isec = shp->shm_perm.security;

5294
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5295 5296
	ad.u.ipc_id = shp->shm_perm.key;

5297
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5298 5299 5300 5301 5302 5303 5304 5305 5306
			    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;

5307
	switch (cmd) {
L
Linus Torvalds 已提交
5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329
	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;
	}

5330
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343
	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;

5344
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5345 5346 5347 5348 5349 5350
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5351
	struct common_audit_data ad;
5352
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5353 5354 5355 5356 5357 5358 5359 5360
	int rc;

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

	isec = sma->sem_perm.security;

5361
	ad.type = LSM_AUDIT_DATA_IPC;
5362
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5363

5364
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380
			  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;
5381
	struct common_audit_data ad;
5382
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5383 5384 5385

	isec = sma->sem_perm.security;

5386
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5387 5388
	ad.u.ipc_id = sma->sem_perm.key;

5389
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5390 5391 5392 5393 5394 5395 5396 5397 5398
			    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;

5399
	switch (cmd) {
L
Linus Torvalds 已提交
5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430
	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;
	}

5431
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444
	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;

5445
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460
}

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;

5461
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5462 5463
}

5464 5465 5466 5467 5468 5469
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5470
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5471 5472 5473 5474 5475 5476
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5477
			       char *name, char **value)
L
Linus Torvalds 已提交
5478
{
5479
	const struct task_security_struct *__tsec;
5480
	u32 sid;
L
Linus Torvalds 已提交
5481
	int error;
5482
	unsigned len;
L
Linus Torvalds 已提交
5483 5484

	if (current != p) {
5485
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5486 5487 5488 5489
		if (error)
			return error;
	}

5490 5491
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5492 5493

	if (!strcmp(name, "current"))
5494
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5495
	else if (!strcmp(name, "prev"))
5496
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5497
	else if (!strcmp(name, "exec"))
5498
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5499
	else if (!strcmp(name, "fscreate"))
5500
		sid = __tsec->create_sid;
5501
	else if (!strcmp(name, "keycreate"))
5502
		sid = __tsec->keycreate_sid;
5503
	else if (!strcmp(name, "sockcreate"))
5504
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5505
	else
5506 5507
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5508 5509 5510 5511

	if (!sid)
		return 0;

5512 5513 5514 5515
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5516 5517 5518 5519

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5520 5521 5522 5523 5524 5525
}

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
5526
	struct task_struct *tracer;
D
David Howells 已提交
5527 5528
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543
	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"))
5544
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5545
	else if (!strcmp(name, "fscreate"))
5546
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5547
	else if (!strcmp(name, "keycreate"))
5548
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5549
	else if (!strcmp(name, "sockcreate"))
5550
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5551
	else if (!strcmp(name, "current"))
5552
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563
	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--;
		}
5564
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5565
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580
			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);

5581
				return error;
5582
			}
5583 5584 5585
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5586 5587 5588 5589
		if (error)
			return error;
	}

D
David Howells 已提交
5590 5591 5592 5593
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5594 5595 5596
	/* 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
5597
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5598 5599
	   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
5600 5601
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5602
		tsec->exec_sid = sid;
D
David Howells 已提交
5603
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5604
		tsec->create_sid = sid;
D
David Howells 已提交
5605
	} else if (!strcmp(name, "keycreate")) {
5606 5607
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5608
			goto abort_change;
5609
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5610
	} else if (!strcmp(name, "sockcreate")) {
5611
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5612 5613
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5614
		if (sid == 0)
D
David Howells 已提交
5615 5616 5617 5618
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5619
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5620 5621 5622
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5623
		}
L
Linus Torvalds 已提交
5624 5625 5626

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5627
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5628
		if (error)
D
David Howells 已提交
5629
			goto abort_change;
L
Linus Torvalds 已提交
5630 5631 5632

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5633
		ptsid = 0;
5634
		rcu_read_lock();
5635
		tracer = ptrace_parent(p);
D
David Howells 已提交
5636 5637
		if (tracer)
			ptsid = task_sid(tracer);
5638
		rcu_read_unlock();
D
David Howells 已提交
5639 5640 5641 5642

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5643
			if (error)
D
David Howells 已提交
5644
				goto abort_change;
L
Linus Torvalds 已提交
5645 5646
		}

D
David Howells 已提交
5647 5648 5649 5650 5651 5652 5653
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5654
	return size;
D
David Howells 已提交
5655 5656 5657 5658

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5659 5660
}

5661 5662 5663 5664 5665
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5666 5667 5668 5669 5670
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5671
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5672
{
5673
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5674 5675
}

5676 5677
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5678
	kfree(secdata);
5679 5680
}

5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699 5700 5701 5702 5703 5704 5705 5706
/*
 *	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;
}
5707 5708
#ifdef CONFIG_KEYS

D
David Howells 已提交
5709
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5710
			     unsigned long flags)
5711
{
D
David Howells 已提交
5712
	const struct task_security_struct *tsec;
5713 5714 5715 5716 5717 5718
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5719 5720 5721
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5722
	else
D
David Howells 已提交
5723
		ksec->sid = tsec->sid;
5724

5725
	k->security = ksec;
5726 5727 5728 5729 5730 5731 5732 5733 5734 5735 5736 5737
	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
5738
				  const struct cred *cred,
5739
				  unsigned perm)
5740 5741 5742
{
	struct key *key;
	struct key_security_struct *ksec;
5743
	u32 sid;
5744 5745 5746 5747 5748 5749 5750

	/* 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
5751
	sid = cred_sid(cred);
5752 5753 5754 5755 5756

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5757 5758
}

5759 5760 5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772
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;
}

5773 5774
#endif

L
Linus Torvalds 已提交
5775
static struct security_operations selinux_ops = {
5776 5777
	.name =				"selinux",

5778
	.ptrace_access_check =		selinux_ptrace_access_check,
5779
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5780
	.capget =			selinux_capget,
D
David Howells 已提交
5781
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5782 5783 5784 5785 5786 5787 5788 5789
	.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,

5790 5791 5792
	.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
5793 5794 5795 5796 5797
	.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,
5798
	.sb_remount =			selinux_sb_remount,
5799
	.sb_kern_mount =		selinux_sb_kern_mount,
5800
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5801 5802 5803
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5804
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5805
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5806 5807
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5808
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5809 5810 5811

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5812
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830
	.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,
5831 5832 5833
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5834
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5835 5836 5837 5838 5839

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5840 5841
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5842 5843 5844 5845 5846 5847 5848
	.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,

5849
	.file_open =			selinux_file_open,
5850

L
Linus Torvalds 已提交
5851
	.task_create =			selinux_task_create,
5852
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5853
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5854
	.cred_prepare =			selinux_cred_prepare,
5855
	.cred_transfer =		selinux_cred_transfer,
5856 5857
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5858
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5859 5860
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5861
	.task_getsid =			selinux_task_getsid,
5862
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5863
	.task_setnice =			selinux_task_setnice,
5864
	.task_setioprio =		selinux_task_setioprio,
5865
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5866 5867 5868
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5869
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5870 5871
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5872
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5873 5874

	.ipc_permission =		selinux_ipc_permission,
5875
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892

	.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,

5893 5894
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5895 5896 5897 5898
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5899
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5900

5901 5902
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5903

5904
	.ismaclabel =			selinux_ismaclabel,
5905
	.secid_to_secctx =		selinux_secid_to_secctx,
5906
	.secctx_to_secid =		selinux_secctx_to_secid,
5907
	.release_secctx =		selinux_release_secctx,
5908 5909 5910
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5911

5912
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926 5927 5928
	.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
5929 5930
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5931 5932
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5933
	.sk_clone_security =		selinux_sk_clone_security,
5934
	.sk_getsecid =			selinux_sk_getsecid,
5935 5936 5937
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5938
	.inet_conn_established =	selinux_inet_conn_established,
5939 5940 5941
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5942
	.req_classify_flow =		selinux_req_classify_flow,
5943 5944
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5945
	.tun_dev_create =		selinux_tun_dev_create,
5946
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5947
	.tun_dev_attach =		selinux_tun_dev_attach,
5948
	.tun_dev_open =			selinux_tun_dev_open,
5949
	.skb_owned_by =			selinux_skb_owned_by,
5950 5951 5952 5953 5954

#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
5955
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5956 5957
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5958
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5959
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5960
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5961 5962
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5963
#endif
5964 5965

#ifdef CONFIG_KEYS
5966 5967 5968
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5969
	.key_getsecurity =		selinux_key_getsecurity,
5970
#endif
5971 5972 5973 5974 5975 5976 5977

#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
5978 5979 5980 5981
};

static __init int selinux_init(void)
{
5982 5983 5984 5985 5986
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5987 5988 5989 5990 5991 5992 5993 5994
	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
5995
	cred_init_security();
L
Linus Torvalds 已提交
5996

5997 5998
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5999 6000
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
6001
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
6002 6003
	avc_init();

6004
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
6005 6006
		panic("SELinux: Unable to register with kernel.\n");

6007 6008 6009
	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC netcache callback\n");

6010
	if (selinux_enforcing)
6011
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6012
	else
6013
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6014

L
Linus Torvalds 已提交
6015 6016 6017
	return 0;
}

6018 6019 6020 6021 6022
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
6023 6024
void selinux_complete_init(void)
{
6025
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
6026 6027

	/* Set up any superblocks initialized prior to the policy load. */
6028
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6029
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
6030 6031 6032 6033 6034 6035
}

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

6036
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
6037

6038 6039 6040 6041
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
6042
		.pf =		NFPROTO_IPV4,
6043 6044 6045 6046 6047 6048
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
6049
		.pf =		NFPROTO_IPV4,
6050 6051
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6052 6053 6054 6055
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6056
		.pf =		NFPROTO_IPV4,
6057 6058
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6059
	}
L
Linus Torvalds 已提交
6060 6061 6062 6063
};

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

6064 6065 6066 6067
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6068
		.pf =		NFPROTO_IPV6,
6069 6070 6071 6072 6073 6074
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6075
		.pf =		NFPROTO_IPV6,
6076 6077 6078
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
6079 6080 6081 6082 6083 6084 6085 6086 6087 6088
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
6089 6090 6091

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

6092 6093 6094
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
6095 6096

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6097 6098 6099
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
6100
#endif	/* IPV6 */
6101

L
Linus Torvalds 已提交
6102 6103 6104 6105 6106 6107 6108 6109 6110
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6111
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6112

6113
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
6114
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6115
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
6116 6117 6118 6119
#endif	/* IPV6 */
}
#endif

6120
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6121 6122 6123 6124 6125

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6126
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6127 6128

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6129 6130
static int selinux_disabled;

L
Linus Torvalds 已提交
6131 6132 6133 6134 6135 6136 6137 6138 6139 6140 6141 6142 6143 6144 6145
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;
6146
	selinux_enabled = 0;
L
Linus Torvalds 已提交
6147

6148
	reset_security_ops();
L
Linus Torvalds 已提交
6149

6150 6151 6152
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
6153 6154 6155 6156 6157 6158 6159 6160 6161
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif