hooks.c 150.2 KB
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/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
 *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
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 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
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 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
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 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
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 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
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 *			    <dgoeddel@trustedcs.com>
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 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
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 *	Paul Moore <paul@paul-moore.com>
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 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
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 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
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 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
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 *	as published by the Free Software Foundation.
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 */

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

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

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

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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

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

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

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

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

	return 0;
}

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

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

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

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

	return 0;
}

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

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

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

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

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

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

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#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

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

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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static int sb_finish_set_opts(struct super_block *sb)
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{
	struct superblock_security_struct *sbsec = sb->s_security;
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	struct dentry *root = sb->s_root;
	struct inode *root_inode = root->d_inode;
	int rc = 0;
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	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
		if (!root_inode->i_op->getxattr) {
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			printk(KERN_WARNING "SELinux: (dev %s, type "SB_TYPE_FMT") has no "
			       "xattr support\n", sb->s_id, SB_TYPE_ARGS(sb));
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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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				       SB_TYPE_FMT") has no security xattr handler\n",
				       sb->s_id, SB_TYPE_ARGS(sb));
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			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
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				       SB_TYPE_FMT") getxattr errno %d\n", sb->s_id,
				       SB_TYPE_ARGS(sb), -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 "SB_TYPE_FMT"), unknown behavior\n",
		       sb->s_id, SB_TYPE_ARGS(sb));
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	else
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		printk(KERN_DEBUG "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), %s\n",
		       sb->s_id, SB_TYPE_ARGS(sb),
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		       labeling_behaviors[sbsec->behavior-1]);
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	sbsec->flags |= SE_SBINITIALIZED;
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	if (selinux_is_sblabel_mnt(sb))
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		sbsec->flags |= SBLABEL_MNT;
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	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
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	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		list_del_init(&isec->list);
		goto next_inode;
	}
	spin_unlock(&sbsec->isec_lock);
out:
	return rc;
}
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/*
 * This function should allow an FS to ask what it's mount security
 * options were so it can use those later for submounts, displaying
 * mount options, or whatever.
 */
static int selinux_get_mnt_opts(const struct super_block *sb,
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				struct security_mnt_opts *opts)
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{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
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	security_init_mnt_opts(opts);
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	if (!(sbsec->flags & SE_SBINITIALIZED))
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		return -EINVAL;
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	if (!ss_initialized)
		return -EINVAL;
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	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

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	tmp = sbsec->flags & SE_MNTMASK;
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	/* count the number of mount options for this sb */
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	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
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		if (tmp & 0x01)
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			opts->num_mnt_opts++;
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		tmp >>= 1;
	}
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	/* Check if the Label support flag is set */
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	if (sbsec->flags & SBLABEL_MNT)
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		opts->num_mnt_opts++;
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	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
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		rc = -ENOMEM;
		goto out_free;
	}
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	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
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		rc = -ENOMEM;
		goto out_free;
	}
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	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
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	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
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	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
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	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
		struct inode *root = sbsec->sb->s_root->d_inode;
		struct inode_security_struct *isec = root->i_security;
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		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
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		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
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	}
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	if (sbsec->flags & SBLABEL_MNT) {
559
		opts->mnt_opts[i] = NULL;
560
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
561
	}
L
Linus Torvalds 已提交
562

563
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
564

565 566 567
	return 0;

out_free:
568
	security_free_mnt_opts(opts);
569 570
	return rc;
}
L
Linus Torvalds 已提交
571

572 573 574
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
575 576
	char mnt_flags = sbsec->flags & SE_MNTMASK;

577
	/* check if the old mount command had the same options */
578
	if (sbsec->flags & SE_SBINITIALIZED)
579 580 581 582 583 584 585
		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
	 */
586 587
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
588 589 590
			return 1;
	return 0;
}
591

592 593 594 595
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
596
static int selinux_set_mnt_opts(struct super_block *sb,
597 598 599
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
600
{
601
	const struct cred *cred = current_cred();
602 603
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
604 605
	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
606 607
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
608 609 610
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
611 612 613 614 615 616 617 618 619 620 621

	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
622 623
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
624
		goto out;
625
	}
626 627 628 629 630 631
	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
632

633 634 635 636 637 638 639 640 641 642 643
	/*
	 * 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)
	 */
644
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
645
	    && (num_opts == 0))
646
		goto out;
647

648 649 650 651 652 653 654
	/*
	 * 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;
655

656
		if (flags[i] == SBLABEL_MNT)
657
			continue;
658 659
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
660 661
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
662 663
			       "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
			       mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707
			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
708
		}
709 710
	}

711
	if (sbsec->flags & SE_SBINITIALIZED) {
712
		/* previously mounted with options, but not on this attempt? */
713
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
714 715 716 717 718
			goto out_double_mount;
		rc = 0;
		goto out;
	}

719
	if (strcmp(sb->s_type->name, "proc") == 0)
720
		sbsec->flags |= SE_SBPROC;
721

722 723 724 725 726
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
727
		rc = security_fs_use(sb);
728 729 730 731 732 733
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
734 735 736
	}
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
737
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
738
		if (rc)
739
			goto out;
L
Linus Torvalds 已提交
740

741
		sbsec->sid = fscontext_sid;
742 743 744 745 746 747 748
	}

	/*
	 * 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.
	 */
749 750 751 752 753
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

754 755
	if (context_sid) {
		if (!fscontext_sid) {
756 757
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
758
			if (rc)
759 760
				goto out;
			sbsec->sid = context_sid;
761
		} else {
762 763
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
764
			if (rc)
765
				goto out;
766
		}
767 768
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
769

770
		sbsec->mntpoint_sid = context_sid;
771
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
772 773
	}

774
	if (rootcontext_sid) {
775 776
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
777
		if (rc)
778
			goto out;
779

780 781
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
782 783
	}

784
	if (defcontext_sid) {
785 786
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
787 788 789 790
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
791 792
		}

793 794
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
795
							     sbsec, cred);
796 797 798
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
799

800
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
801 802
	}

803
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
804
out:
805
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
806
	return rc;
807 808 809
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
810 811
	       "security settings for (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
	       SB_TYPE_ARGS(sb));
812
	goto out;
L
Linus Torvalds 已提交
813 814
}

815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845
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,
846
					struct super_block *newsb)
L
Linus Torvalds 已提交
847
{
848 849
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
850

851 852 853
	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
854

855 856
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
857
	 * mount options.  thus we can safely deal with this superblock later
858
	 */
859
	if (!ss_initialized)
860
		return 0;
861 862

	/* how can we clone if the old one wasn't set up?? */
863
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
864

865
	/* if fs is reusing a sb, make sure that the contexts match */
866
	if (newsbsec->flags & SE_SBINITIALIZED)
867
		return selinux_cmp_sb_context(oldsb, newsb);
868

869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887
	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
888
	}
889 890 891 892 893
	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
894

895
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
896 897
	}

898 899
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
900
	return 0;
901 902
}

903 904
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
905
{
906
	char *p;
907 908
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
909
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
910

911
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
912

913 914 915 916
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
917

918 919
		if (!*p)
			continue;
L
Linus Torvalds 已提交
920

921
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
922

923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974
		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;
975 976
		case Opt_labelsupport:
			break;
977 978 979 980
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
981 982 983

		}
	}
984

985 986 987 988 989 990 991 992 993 994 995
	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;
	}

996
	if (fscontext) {
997 998
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
999 1000
	}
	if (context) {
1001 1002
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1003 1004
	}
	if (rootcontext) {
1005 1006
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1007 1008
	}
	if (defcontext) {
1009 1010
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1011 1012
	}

1013 1014 1015
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1016 1017 1018 1019 1020
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1021 1022
	return rc;
}
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043
/*
 * 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:
1044
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1045 1046 1047 1048 1049

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1050

A
Adrian Bunk 已提交
1051 1052
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1053 1054 1055 1056 1057
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1058 1059 1060 1061 1062 1063
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077

		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;
1078
		case SBLABEL_MNT:
1079 1080 1081
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1082 1083
		default:
			BUG();
1084
			return;
1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102
		};
		/* 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);
1103 1104 1105 1106
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1107
		return rc;
1108
	}
1109 1110 1111 1112 1113 1114 1115 1116

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139
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;
}

1140 1141 1142 1143 1144 1145 1146 1147 1148 1149
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
1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165
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:
1166 1167 1168 1169
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1170
		case SOCK_DGRAM:
1171 1172 1173 1174
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1175 1176
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1177
		default:
L
Linus Torvalds 已提交
1178 1179 1180 1181 1182 1183 1184 1185 1186
			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;
1187
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200
			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;
1201 1202
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1203 1204 1205 1206 1207 1208 1209
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1210 1211
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1212 1213 1214 1215 1216 1217
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1218
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1219 1220 1221
				u16 tclass,
				u32 *sid)
{
1222 1223
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1224

1225
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1226 1227 1228
	if (!buffer)
		return -ENOMEM;

1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240
	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
1241 1242 1243 1244 1245
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1246
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268
				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;

1269
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1270
	if (isec->initialized)
1271
		goto out_unlock;
L
Linus Torvalds 已提交
1272 1273

	sbsec = inode->i_sb->s_security;
1274
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1275 1276 1277 1278 1279 1280 1281
		/* 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);
1282
		goto out_unlock;
L
Linus Torvalds 已提交
1283 1284 1285
	}

	switch (sbsec->behavior) {
1286 1287
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303
	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) {
1304 1305 1306 1307 1308 1309 1310 1311 1312
			/*
			 * 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.
			 */
1313
			goto out_unlock;
L
Linus Torvalds 已提交
1314 1315 1316
		}

		len = INITCONTEXTLEN;
1317
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1318 1319 1320
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1321
			goto out_unlock;
L
Linus Torvalds 已提交
1322
		}
1323
		context[len] = '\0';
L
Linus Torvalds 已提交
1324 1325 1326
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1327 1328
			kfree(context);

L
Linus Torvalds 已提交
1329 1330 1331 1332 1333
			/* 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);
1334
				goto out_unlock;
L
Linus Torvalds 已提交
1335 1336
			}
			len = rc;
1337
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1338 1339 1340
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1341
				goto out_unlock;
L
Linus Torvalds 已提交
1342
			}
1343
			context[len] = '\0';
L
Linus Torvalds 已提交
1344 1345 1346 1347 1348 1349 1350
			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
1351
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1352
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1353 1354
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1355
				goto out_unlock;
L
Linus Torvalds 已提交
1356 1357 1358 1359 1360
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1361
			rc = security_context_to_sid_default(context, rc, &sid,
1362 1363
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1364
			if (rc) {
1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377
				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
1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395
				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);
1396 1397
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1398
		if (rc)
1399
			goto out_unlock;
L
Linus Torvalds 已提交
1400 1401
		isec->sid = sid;
		break;
1402 1403 1404
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1405
	default:
1406
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1407 1408
		isec->sid = sbsec->sid;

1409
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1410
			if (opt_dentry) {
L
Linus Torvalds 已提交
1411
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1412
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1413 1414 1415
							  isec->sclass,
							  &sid);
				if (rc)
1416
					goto out_unlock;
L
Linus Torvalds 已提交
1417 1418 1419 1420 1421 1422 1423 1424
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1425 1426
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459
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
1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472
/*
 * 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);
}

1473
/*
1474
 * Check permission between a pair of tasks, e.g. signal checks,
1475 1476
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1477
 * - this uses the default subjective creds of tsk1
1478 1479 1480
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1481 1482
			 u32 perms)
{
1483 1484
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1485

1486 1487 1488 1489 1490
	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
1491 1492
}

1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508
/*
 * 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);
}

1509 1510 1511 1512
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1513
/* Check whether a task is allowed to use a capability. */
1514
static int cred_has_capability(const struct cred *cred,
1515
			       int cap, int audit)
L
Linus Torvalds 已提交
1516
{
1517
	struct common_audit_data ad;
1518
	struct av_decision avd;
1519
	u16 sclass;
1520
	u32 sid = cred_sid(cred);
1521
	u32 av = CAP_TO_MASK(cap);
1522
	int rc;
L
Linus Torvalds 已提交
1523

1524
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1525 1526
	ad.u.cap = cap;

1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
	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();
1538
		return -EINVAL;
1539
	}
1540

1541
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1542
	if (audit == SECURITY_CAP_AUDIT) {
1543
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1544 1545 1546
		if (rc2)
			return rc2;
	}
1547
	return rc;
L
Linus Torvalds 已提交
1548 1549 1550 1551 1552 1553
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1554
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1555

1556
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1557 1558 1559 1560 1561 1562
			    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). */
1563
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1564 1565
			  struct inode *inode,
			  u32 perms,
1566
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1567 1568
{
	struct inode_security_struct *isec;
1569
	u32 sid;
L
Linus Torvalds 已提交
1570

1571 1572
	validate_creds(cred);

1573
	if (unlikely(IS_PRIVATE(inode)))
1574 1575
		return 0;

1576
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1577 1578
	isec = inode->i_security;

1579
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1580 1581 1582 1583 1584
}

/* 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. */
1585
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1586 1587 1588 1589
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1590
	struct common_audit_data ad;
1591

1592
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1593
	ad.u.dentry = dentry;
1594
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606
}

/* 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;

1607
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1608
	ad.u.path = *path;
1609
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1610 1611
}

1612 1613 1614 1615 1616 1617 1618 1619 1620
/* 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;
1621
	return inode_has_perm(cred, file_inode(file), av, &ad);
1622 1623
}

L
Linus Torvalds 已提交
1624 1625 1626 1627 1628 1629 1630 1631
/* 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. */
1632 1633 1634
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1635 1636
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1637
	struct inode *inode = file_inode(file);
1638
	struct common_audit_data ad;
1639
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1640 1641
	int rc;

1642
	ad.type = LSM_AUDIT_DATA_PATH;
1643
	ad.u.path = file->f_path;
L
Linus Torvalds 已提交
1644

1645 1646
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1647 1648 1649 1650
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1651
			goto out;
L
Linus Torvalds 已提交
1652 1653 1654
	}

	/* av is zero if only checking access to the descriptor. */
1655
	rc = 0;
L
Linus Torvalds 已提交
1656
	if (av)
1657
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1658

1659 1660
out:
	return rc;
L
Linus Torvalds 已提交
1661 1662 1663 1664 1665 1666 1667
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1668
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1669 1670
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1671
	u32 sid, newsid;
1672
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1673 1674 1675 1676 1677
	int rc;

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

1678 1679 1680
	sid = tsec->sid;
	newsid = tsec->create_sid;

1681
	ad.type = LSM_AUDIT_DATA_DENTRY;
1682
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1683

1684
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1685 1686 1687 1688 1689
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1690
	if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1691 1692
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1693 1694 1695 1696
		if (rc)
			return rc;
	}

1697
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1698 1699 1700 1701 1702 1703 1704 1705
	if (rc)
		return rc;

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

1706 1707 1708 1709
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1710
	u32 sid = task_sid(ctx);
1711

1712
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1713 1714
}

1715 1716 1717
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1718 1719 1720 1721 1722 1723 1724 1725

/* 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;
1726
	struct common_audit_data ad;
1727
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1728 1729 1730 1731 1732 1733
	u32 av;
	int rc;

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

1734
	ad.type = LSM_AUDIT_DATA_DENTRY;
1735
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1736 1737 1738

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1739
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753
	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
1754 1755
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1756 1757 1758
		return 0;
	}

1759
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1760 1761 1762 1763 1764 1765 1766 1767 1768
	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;
1769
	struct common_audit_data ad;
1770
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1771 1772 1773 1774 1775 1776 1777 1778 1779
	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;

1780
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1781

1782
	ad.u.dentry = old_dentry;
1783
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1784 1785 1786
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1787
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1788 1789 1790 1791
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1792
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1793 1794 1795 1796 1797
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1798
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1799 1800 1801
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1802
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1803 1804 1805 1806 1807
	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);
1808
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1809 1810 1811 1812 1813 1814 1815 1816 1817 1818
				  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. */
1819
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1820 1821
			       struct super_block *sb,
			       u32 perms,
1822
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1823 1824
{
	struct superblock_security_struct *sbsec;
1825
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1826 1827

	sbsec = sb->s_security;
1828
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1829 1830 1831 1832 1833 1834 1835
}

/* 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
1836
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
		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;
}

1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881
/* 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
1882
/*
1883
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1884 1885
 * open permission.
 */
1886
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1887
{
1888
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1889

1890 1891 1892
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1893 1894 1895
	return av;
}

L
Linus Torvalds 已提交
1896 1897
/* Hook functions begin here. */

1898
static int selinux_ptrace_access_check(struct task_struct *child,
1899
				     unsigned int mode)
L
Linus Torvalds 已提交
1900 1901 1902
{
	int rc;

1903
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1904 1905 1906
	if (rc)
		return rc;

1907
	if (mode & PTRACE_MODE_READ) {
1908 1909 1910
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1911 1912
	}

1913
	return current_has_perm(child, PROCESS__PTRACE);
1914 1915 1916 1917 1918 1919
}

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

1920
	rc = cap_ptrace_traceme(parent);
1921 1922 1923 1924
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1925 1926 1927
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1928
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1929 1930 1931
{
	int error;

1932
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1933 1934 1935
	if (error)
		return error;

1936
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1937 1938
}

D
David Howells 已提交
1939 1940 1941 1942
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
1943 1944 1945
{
	int error;

1946
	error = cap_capset(new, old,
D
David Howells 已提交
1947
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1948 1949 1950
	if (error)
		return error;

D
David Howells 已提交
1951
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1952 1953
}

1954 1955 1956 1957 1958 1959 1960 1961 1962 1963
/*
 * (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.
 */

1964 1965
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1966 1967 1968
{
	int rc;

1969
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1970 1971 1972
	if (rc)
		return rc;

1973
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1974 1975 1976 1977
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1978
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1979 1980 1981 1982 1983 1984
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1985 1986 1987 1988 1989
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1990
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1991 1992 1993 1994
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1995
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1996 1997 1998 1999
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2000 2001 2002 2003 2004 2005
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2006 2007
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2008
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2009 2010
}

2011
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2012 2013 2014 2015
{
	int rc;

	switch (type) {
2016 2017
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2018 2019
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
2020 2021 2022 2023
	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:
2024 2025
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
2026 2027 2028 2029 2030
	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 */
2031 2032 2033
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045
	}
	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.
 */
2046
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2047 2048 2049
{
	int rc, cap_sys_admin = 0;

2050
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2051
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
2052 2053 2054
	if (rc == 0)
		cap_sys_admin = 1;

2055
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
2056 2057 2058 2059
}

/* binprm security operations */

2060
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2061
{
2062 2063
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2064
	struct inode_security_struct *isec;
2065
	struct common_audit_data ad;
A
Al Viro 已提交
2066
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2067 2068
	int rc;

2069
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
2070 2071 2072
	if (rc)
		return rc;

2073 2074 2075
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2076 2077
		return 0;

2078 2079
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2080 2081 2082
	isec = inode->i_security;

	/* Default to the current task SID. */
2083 2084
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2085

2086
	/* Reset fs, key, and sock SIDs on execve. */
2087 2088 2089
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2090

2091 2092
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2093
		/* Reset exec SID on execve. */
2094
		new_tsec->exec_sid = 0;
2095 2096 2097 2098 2099 2100 2101

		/*
		 * Minimize confusion: if no_new_privs and a transition is
		 * explicitly requested, then fail the exec.
		 */
		if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
			return -EPERM;
L
Linus Torvalds 已提交
2102 2103
	} else {
		/* Check for a default transition on this program. */
2104
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2105 2106
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2107 2108 2109 2110
		if (rc)
			return rc;
	}

2111
	ad.type = LSM_AUDIT_DATA_PATH;
2112
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2113

2114 2115
	if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
	    (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2116
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2117

2118 2119
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2120 2121 2122 2123 2124
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2125
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2126 2127 2128 2129
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2130
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2131 2132 2133 2134
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152
		/* 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();
2153
			tracer = ptrace_parent(current);
2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167
			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
2168

2169 2170
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2171 2172 2173 2174 2175
	}

	return 0;
}

2176
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2177
{
2178
	const struct task_security_struct *tsec = current_security();
2179
	u32 sid, osid;
L
Linus Torvalds 已提交
2180 2181
	int atsecure = 0;

2182 2183 2184 2185
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2186 2187 2188
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2189
		atsecure = avc_has_perm(osid, sid,
2190 2191
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2192 2193
	}

2194
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2195 2196
}

A
Al Viro 已提交
2197 2198 2199 2200 2201
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
2202
/* Derived from fs/exec.c:flush_old_files. */
2203 2204
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2205 2206
{
	struct file *file, *devnull = NULL;
2207
	struct tty_struct *tty;
2208
	int drop_tty = 0;
A
Al Viro 已提交
2209
	unsigned n;
L
Linus Torvalds 已提交
2210

2211
	tty = get_current_tty();
L
Linus Torvalds 已提交
2212
	if (tty) {
N
Nick Piggin 已提交
2213
		spin_lock(&tty_files_lock);
2214
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2215
			struct tty_file_private *file_priv;
2216

L
Linus Torvalds 已提交
2217
			/* Revalidate access to controlling tty.
2218 2219 2220 2221
			   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
2222 2223 2224
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2225
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2226
				drop_tty = 1;
L
Linus Torvalds 已提交
2227
		}
N
Nick Piggin 已提交
2228
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2229
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2230
	}
2231 2232 2233
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2234 2235

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2236 2237 2238
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2239

A
Al Viro 已提交
2240
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2241 2242 2243 2244 2245 2246 2247
	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
2248
		fput(devnull);
L
Linus Torvalds 已提交
2249 2250
}

2251 2252 2253 2254
/*
 * 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
2255
{
2256 2257 2258
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2259

2260 2261 2262
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2263

2264 2265
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2266

2267 2268
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2269

2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282
	/* 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) {
2283 2284
		/* protect against do_prlimit() */
		task_lock(current);
2285 2286 2287 2288
		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
2289
		}
2290 2291
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2292 2293 2294 2295
	}
}

/*
2296 2297
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2298
 */
2299
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2300
{
2301
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2302
	struct itimerval itimer;
2303
	u32 osid, sid;
L
Linus Torvalds 已提交
2304 2305
	int rc, i;

2306 2307 2308 2309
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2310 2311
		return;

2312 2313 2314 2315 2316 2317 2318 2319
	/* 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
2320 2321 2322 2323 2324
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2325 2326 2327 2328 2329
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2330 2331 2332
		spin_unlock_irq(&current->sighand->siglock);
	}

2333 2334
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2335
	read_lock(&tasklist_lock);
2336
	__wake_up_parent(current, current->real_parent);
2337
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361
}

/* 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)
{
2362 2363 2364
	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) ||
2365 2366
		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
2367 2368 2369 2370 2371 2372 2373
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2374
	} else
L
Linus Torvalds 已提交
2375 2376 2377 2378 2379
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2380 2381
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2382 2383 2384 2385 2386 2387
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2388
	} else
2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400
		*first = 0;

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

2401
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2402 2403 2404 2405
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2406
	int open_quote = 0;
L
Linus Torvalds 已提交
2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421

	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 {
2422 2423 2424 2425
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2426 2427 2428
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2429
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2430 2431 2432 2433 2434 2435 2436
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2437
	strcpy(in_save, nosec_save);
2438
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2439 2440 2441 2442
out:
	return rc;
}

2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477
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;

2478
		if (flags[i] == SBLABEL_MNT)
2479 2480 2481 2482 2483
			continue;
		len = strlen(mount_options[i]);
		rc = security_context_to_sid(mount_options[i], len, &sid);
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
2484 2485
			       "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
			       mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
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 2520 2521 2522
			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 "
2523 2524
	       "during remount (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
	       SB_TYPE_ARGS(sb));
2525 2526 2527
	goto out_free_opts;
}

2528
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2529
{
2530
	const struct cred *cred = current_cred();
2531
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2532 2533 2534 2535 2536 2537
	int rc;

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

2538 2539 2540 2541
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2542
	ad.type = LSM_AUDIT_DATA_DENTRY;
2543
	ad.u.dentry = sb->s_root;
2544
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2545 2546
}

2547
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2548
{
2549
	const struct cred *cred = current_cred();
2550
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2551

2552
	ad.type = LSM_AUDIT_DATA_DENTRY;
2553
	ad.u.dentry = dentry->d_sb->s_root;
2554
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2555 2556
}

A
Al Viro 已提交
2557
static int selinux_mount(const char *dev_name,
2558
			 struct path *path,
A
Al Viro 已提交
2559
			 const char *type,
2560 2561
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2562
{
2563
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2564 2565

	if (flags & MS_REMOUNT)
2566
		return superblock_has_perm(cred, path->dentry->d_sb,
2567
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2568
	else
E
Eric Paris 已提交
2569
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2570 2571 2572 2573
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2574
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2575

2576
	return superblock_has_perm(cred, mnt->mnt_sb,
2577
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591
}

/* 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);
}

2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625
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);
}

2626
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2627 2628
				       const struct qstr *qstr,
				       const char **name,
2629
				       void **value, size_t *len)
2630
{
2631
	const struct task_security_struct *tsec = current_security();
2632 2633
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2634
	u32 sid, newsid, clen;
2635
	int rc;
2636
	char *context;
2637 2638 2639 2640

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

2641 2642 2643
	sid = tsec->sid;
	newsid = tsec->create_sid;

2644 2645 2646
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
2647
	else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2648
		rc = security_transition_sid(sid, dsec->sid,
2649
					     inode_mode_to_security_class(inode->i_mode),
2650
					     qstr, &newsid);
2651 2652 2653 2654
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2655
			       __func__,
2656 2657 2658 2659 2660
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2661
	/* Possibly defer initialization to selinux_complete_init. */
2662
	if (sbsec->flags & SE_SBINITIALIZED) {
2663 2664 2665 2666 2667
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2668

2669
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2670 2671
		return -EOPNOTSUPP;

2672 2673
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2674

2675
	if (value && len) {
2676
		rc = security_sid_to_context_force(newsid, &context, &clen);
2677
		if (rc)
2678 2679 2680
			return rc;
		*value = context;
		*len = clen;
2681 2682 2683 2684 2685
	}

	return 0;
}

A
Al Viro 已提交
2686
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705
{
	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);
}

2706
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2707 2708 2709 2710 2711 2712 2713 2714 2715
{
	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
2716
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2717 2718 2719 2720 2721
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2722
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2723 2724 2725 2726 2727 2728
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2729 2730
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2731
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2732 2733 2734 2735
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2736
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2737

E
Eric Paris 已提交
2738
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2739 2740
}

2741 2742 2743
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
					   unsigned flags)
L
Linus Torvalds 已提交
2744
{
2745
	struct common_audit_data ad;
2746 2747 2748
	struct inode_security_struct *isec = inode->i_security;
	int rc;

2749
	ad.type = LSM_AUDIT_DATA_INODE;
2750 2751 2752 2753 2754 2755 2756 2757 2758
	ad.u.inode = inode;

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

2759
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2760
{
2761
	const struct cred *cred = current_cred();
2762 2763
	u32 perms;
	bool from_access;
2764
	unsigned flags = mask & MAY_NOT_BLOCK;
2765 2766 2767 2768 2769
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
2770

2771
	from_access = mask & MAY_ACCESS;
2772 2773
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2774 2775
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2776 2777
		return 0;

2778
	validate_creds(cred);
2779

2780 2781
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
2782 2783 2784

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

2785 2786 2787 2788 2789 2790 2791 2792 2793 2794
	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;

2795
	rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2796 2797 2798
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
2799 2800 2801 2802
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2803
	const struct cred *cred = current_cred();
2804
	unsigned int ia_valid = iattr->ia_valid;
2805
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
2806

2807 2808 2809 2810 2811 2812 2813
	/* 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
2814

2815 2816
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2817
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2818

2819
	if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2820 2821 2822
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
2823 2824 2825 2826
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2827
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2828 2829 2830 2831
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2832

E
Eric Paris 已提交
2833
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2834 2835
}

2836
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2837
{
2838 2839
	const struct cred *cred = current_cred();

2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853
	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
2854
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2855 2856
}

2857 2858
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
2859 2860 2861 2862
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2863
	struct common_audit_data ad;
2864
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2865 2866
	int rc = 0;

2867 2868
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2869 2870

	sbsec = inode->i_sb->s_security;
2871
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
2872 2873
		return -EOPNOTSUPP;

2874
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2875 2876
		return -EPERM;

2877
	ad.type = LSM_AUDIT_DATA_DENTRY;
2878
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2879

2880
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2881 2882 2883 2884 2885
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2886
	if (rc == -EINVAL) {
2887 2888 2889 2890 2891 2892 2893
		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 */
2894 2895 2896 2897 2898 2899 2900 2901 2902 2903
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
2904 2905 2906 2907 2908
			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);

2909
			return rc;
2910
		}
2911 2912
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2913 2914 2915
	if (rc)
		return rc;

2916
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2917 2918 2919 2920
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2921
	rc = security_validate_transition(isec->sid, newsid, sid,
2922
					  isec->sclass);
L
Linus Torvalds 已提交
2923 2924 2925 2926 2927 2928 2929 2930 2931 2932
	if (rc)
		return rc;

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

2933
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2934
					const void *value, size_t size,
2935
					int flags)
L
Linus Torvalds 已提交
2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946
{
	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;
	}

2947
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2948
	if (rc) {
2949 2950 2951
		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
2952 2953 2954
		return;
	}

2955
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
2956
	isec->sid = newsid;
2957 2958
	isec->initialized = 1;

L
Linus Torvalds 已提交
2959 2960 2961
	return;
}

2962
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2963
{
2964 2965
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2966
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2967 2968
}

2969
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2970
{
2971 2972
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2973
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2974 2975
}

2976
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2977
{
2978 2979
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2980 2981 2982 2983 2984 2985

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

2986
/*
2987
 * Copy the inode security context value to the user.
2988 2989 2990
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2991
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2992
{
2993 2994 2995
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2996
	struct inode_security_struct *isec = inode->i_security;
2997

2998 2999
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3000

3001 3002 3003 3004 3005 3006 3007 3008 3009
	/*
	 * 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.
	 */
3010
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3011
				SECURITY_CAP_NOAUDIT);
3012 3013 3014 3015 3016
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3017 3018 3019 3020 3021 3022 3023 3024 3025 3026
	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
3027 3028 3029
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3030
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041
{
	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;

3042
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
3043 3044 3045
	if (rc)
		return rc;

3046
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3047
	isec->sid = newsid;
3048
	isec->initialized = 1;
L
Linus Torvalds 已提交
3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059
	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;
}

3060 3061 3062 3063 3064 3065
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
3066 3067
/* file security operations */

3068
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3069
{
3070
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3071
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3072 3073 3074 3075 3076

	/* 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;

3077 3078
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3079 3080
}

3081 3082
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3083
	struct inode *inode = file_inode(file);
3084 3085 3086 3087
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

3088
	if (!mask)
3089 3090 3091
		/* No permission to check.  Existence test. */
		return 0;

3092 3093
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3094
		/* No change since file_open check. */
3095 3096
		return 0;

3097 3098 3099
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112
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)
{
3113
	const struct cred *cred = current_cred();
3114
	int error = 0;
L
Linus Torvalds 已提交
3115

3116 3117 3118 3119 3120 3121 3122
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3123
	case FS_IOC_GETFLAGS:
3124
	/* fall through */
3125
	case FS_IOC_GETVERSION:
3126 3127
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3128

3129
	case FS_IOC_SETFLAGS:
3130
	/* fall through */
3131
	case FS_IOC_SETVERSION:
3132 3133 3134 3135 3136 3137 3138 3139 3140
		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
3141

3142 3143
	case KDSKBENT:
	case KDSKBSENT:
3144 3145
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3146 3147 3148 3149 3150 3151 3152 3153 3154
		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
3155 3156
}

3157 3158
static int default_noexec;

L
Linus Torvalds 已提交
3159 3160
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3161
	const struct cred *cred = current_cred();
D
David Howells 已提交
3162
	int rc = 0;
3163

3164 3165
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3166 3167 3168 3169 3170
		/*
		 * 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
3171
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3172
		if (rc)
D
David Howells 已提交
3173
			goto error;
L
Linus Torvalds 已提交
3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186
	}

	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;

3187
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3188
	}
D
David Howells 已提交
3189 3190 3191

error:
	return rc;
L
Linus Torvalds 已提交
3192 3193
}

3194
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3195
{
3196
	int rc = 0;
3197
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3198

3199 3200 3201 3202 3203 3204
	/*
	 * notice that we are intentionally putting the SELinux check before
	 * the secondary cap_file_mmap check.  This is such a likely attempt
	 * at bad behaviour/exploit that we always want to get the AVC, even
	 * if DAC would have also denied the operation.
	 */
3205
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3206 3207
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3208 3209 3210 3211 3212
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
3213 3214
	return cap_mmap_addr(addr);
}
L
Linus Torvalds 已提交
3215

3216 3217 3218
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
L
Linus Torvalds 已提交
3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229
	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)
{
3230
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3231 3232 3233 3234

	if (selinux_checkreqprot)
		prot = reqprot;

3235 3236
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3237
		int rc = 0;
3238 3239
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3240
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3241 3242 3243
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3244
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3245 3246 3247 3248 3249 3250 3251 3252
		} 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
3253
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3254
		}
3255 3256 3257
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3258 3259 3260 3261 3262 3263

	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)
{
3264 3265 3266
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3267 3268 3269 3270 3271
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3272
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3273 3274 3275
	int err = 0;

	switch (cmd) {
3276 3277
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3278
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3279
			break;
3280 3281 3282 3283 3284 3285 3286
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3287
	case F_GETOWNER_UIDS:
3288
		/* Just check FD__USE permission */
3289
		err = file_has_perm(cred, file, 0);
3290 3291 3292 3293
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3294
#if BITS_PER_LONG == 32
3295 3296 3297
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3298
#endif
3299
		err = file_has_perm(cred, file, FILE__LOCK);
3300
		break;
L
Linus Torvalds 已提交
3301 3302 3303 3304 3305 3306 3307 3308 3309 3310
	}

	return err;
}

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

	fsec = file->f_security;
3311
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3312 3313 3314 3315 3316 3317 3318

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3319
	struct file *file;
3320
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3321 3322 3323 3324
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3325
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3326 3327 3328 3329 3330 3331 3332 3333

	fsec = file->f_security;

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

3334
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3335 3336 3337 3338 3339
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3340 3341 3342
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3343 3344
}

3345
static int selinux_file_open(struct file *file, const struct cred *cred)
3346 3347 3348
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3349

3350
	fsec = file->f_security;
A
Al Viro 已提交
3351
	isec = file_inode(file)->i_security;
3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368
	/*
	 * 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.
	 */
3369
	return file_path_has_perm(cred, file, open_file_to_av(file));
3370 3371
}

L
Linus Torvalds 已提交
3372 3373 3374 3375
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3376
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3377 3378
}

3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393
/*
 * 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
3394 3395 3396 3397
/*
 * 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
3398
{
D
David Howells 已提交
3399
	struct task_security_struct *tsec = cred->security;
3400

3401 3402 3403 3404 3405
	/*
	 * 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);
3406
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3407 3408
	kfree(tsec);
}
L
Linus Torvalds 已提交
3409

D
David Howells 已提交
3410 3411 3412 3413 3414 3415 3416 3417
/*
 * 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
3418

D
David Howells 已提交
3419
	old_tsec = old->security;
L
Linus Torvalds 已提交
3420

D
David Howells 已提交
3421 3422 3423
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3424

D
David Howells 已提交
3425
	new->security = tsec;
L
Linus Torvalds 已提交
3426 3427 3428
	return 0;
}

3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439
/*
 * 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;
}

3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480
/*
 * 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;
3481
	return ret;
3482 3483
}

3484
static int selinux_kernel_module_request(char *kmod_name)
3485
{
3486 3487 3488 3489 3490
	u32 sid;
	struct common_audit_data ad;

	sid = task_sid(current);

3491
	ad.type = LSM_AUDIT_DATA_KMOD;
3492 3493 3494 3495
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3496 3497
}

L
Linus Torvalds 已提交
3498 3499
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3500
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3501 3502 3503 3504
}

static int selinux_task_getpgid(struct task_struct *p)
{
3505
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3506 3507 3508 3509
}

static int selinux_task_getsid(struct task_struct *p)
{
3510
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3511 3512
}

3513 3514
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3515
	*secid = task_sid(p);
3516 3517
}

L
Linus Torvalds 已提交
3518 3519 3520 3521
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3522
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3523 3524 3525
	if (rc)
		return rc;

3526
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3527 3528
}

3529 3530
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3531 3532
	int rc;

3533
	rc = cap_task_setioprio(p, ioprio);
3534 3535 3536
	if (rc)
		return rc;

3537
	return current_has_perm(p, PROCESS__SETSCHED);
3538 3539
}

3540 3541
static int selinux_task_getioprio(struct task_struct *p)
{
3542
	return current_has_perm(p, PROCESS__GETSCHED);
3543 3544
}

3545 3546
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3547
{
3548
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3549 3550 3551 3552

	/* 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
3553
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3554
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3555
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3556 3557 3558 3559

	return 0;
}

3560
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3561
{
3562 3563
	int rc;

3564
	rc = cap_task_setscheduler(p);
3565 3566 3567
	if (rc)
		return rc;

3568
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3569 3570 3571 3572
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3573
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3574 3575
}

3576 3577
static int selinux_task_movememory(struct task_struct *p)
{
3578
	return current_has_perm(p, PROCESS__SETSCHED);
3579 3580
}

3581 3582
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3583 3584 3585 3586 3587 3588 3589 3590
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3591
	if (secid)
3592 3593
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3594
	else
3595
		rc = current_has_perm(p, perm);
3596
	return rc;
L
Linus Torvalds 已提交
3597 3598 3599 3600
}

static int selinux_task_wait(struct task_struct *p)
{
3601
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3602 3603 3604 3605 3606 3607
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3608
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3609

3610
	isec->sid = sid;
L
Linus Torvalds 已提交
3611 3612 3613 3614
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3615
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3616
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3617 3618 3619 3620
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3621
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3622 3623 3624 3625 3626 3627 3628 3629
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

3630 3631
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
3632 3633
	ret = 0;

3634 3635 3636
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3637
	switch (ih->protocol) {
3638 3639
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3640

3641 3642
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3643 3644 3645 3646 3647 3648

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

3649 3650
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3651
		break;
3652 3653 3654 3655 3656 3657 3658 3659
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3660
		offset += ihlen;
3661
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3662
		if (uh == NULL)
3663
			break;
L
Linus Torvalds 已提交
3664

3665 3666
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
3667 3668
		break;
	}
L
Linus Torvalds 已提交
3669

J
James Morris 已提交
3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680
	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;

3681 3682
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3683
		break;
3684
	}
J
James Morris 已提交
3685

3686 3687 3688
	default:
		break;
	}
L
Linus Torvalds 已提交
3689 3690 3691 3692 3693 3694 3695
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3696
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3697
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3698 3699 3700 3701
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3702
	__be16 frag_off;
L
Linus Torvalds 已提交
3703

3704
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3705 3706 3707 3708
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

3709 3710
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3711 3712 3713 3714
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3715
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3716 3717 3718
	if (offset < 0)
		goto out;

3719 3720 3721
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3722 3723
	switch (nexthdr) {
	case IPPROTO_TCP: {
3724
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3725 3726 3727 3728 3729

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

3730 3731
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
3732 3733 3734 3735 3736 3737 3738 3739 3740 3741
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

3742 3743
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
3744 3745 3746
		break;
	}

J
James Morris 已提交
3747 3748 3749 3750 3751 3752 3753
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

3754 3755
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
3756
		break;
3757
	}
J
James Morris 已提交
3758

L
Linus Torvalds 已提交
3759 3760 3761 3762 3763 3764 3765 3766 3767 3768
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3769
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3770
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3771
{
3772 3773
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3774

3775
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
3776
	case PF_INET:
3777
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3778 3779
		if (ret)
			goto parse_error;
3780 3781
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
3782
		goto okay;
L
Linus Torvalds 已提交
3783 3784 3785

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3786
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3787 3788
		if (ret)
			goto parse_error;
3789 3790
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
3791
		goto okay;
L
Linus Torvalds 已提交
3792 3793
#endif	/* IPV6 */
	default:
3794 3795
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3796 3797
	}

3798 3799 3800 3801
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3802
	return ret;
3803 3804 3805 3806 3807

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3808 3809
}

3810
/**
3811
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3812
 * @skb: the packet
3813
 * @family: protocol family
3814
 * @sid: the packet's peer label SID
3815 3816
 *
 * Description:
3817 3818 3819 3820 3821 3822
 * 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.
3823 3824
 *
 */
3825
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3826
{
3827
	int err;
3828 3829
	u32 xfrm_sid;
	u32 nlbl_sid;
3830
	u32 nlbl_type;
3831

3832
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3833 3834 3835 3836 3837
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
3838

3839 3840 3841 3842 3843
	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");
3844
		return -EACCES;
3845
	}
3846 3847

	return 0;
3848 3849
}

3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873
/**
 * 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
3874
/* socket security operations */
3875

3876 3877
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3878
{
3879 3880 3881 3882 3883 3884 3885
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3886 3887
}

3888
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3889
{
3890
	struct sk_security_struct *sksec = sk->sk_security;
3891
	struct common_audit_data ad;
3892
	struct lsm_network_audit net = {0,};
3893
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3894

3895 3896
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3897

3898
	ad.type = LSM_AUDIT_DATA_NET;
3899 3900
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
3901

3902
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3903 3904 3905 3906 3907
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3908
	const struct task_security_struct *tsec = current_security();
3909
	u32 newsid;
3910
	u16 secclass;
3911
	int rc;
L
Linus Torvalds 已提交
3912 3913

	if (kern)
3914
		return 0;
3915 3916

	secclass = socket_type_to_security_class(family, type, protocol);
3917 3918 3919 3920
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3921
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3922 3923
}

V
Venkat Yekkirala 已提交
3924 3925
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3926
{
3927
	const struct task_security_struct *tsec = current_security();
3928
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3929
	struct sk_security_struct *sksec;
3930 3931
	int err = 0;

3932 3933
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3934 3935
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3936 3937 3938 3939 3940
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3941

L
Linus Torvalds 已提交
3942 3943
	isec->initialized = 1;

3944 3945 3946
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3947
		sksec->sclass = isec->sclass;
3948
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3949 3950
	}

V
Venkat Yekkirala 已提交
3951
	return err;
L
Linus Torvalds 已提交
3952 3953 3954 3955 3956 3957 3958 3959
}

/* 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)
{
3960
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3961 3962 3963
	u16 family;
	int err;

3964
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3965 3966 3967 3968 3969
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3970 3971
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3972
	 */
3973
	family = sk->sk_family;
L
Linus Torvalds 已提交
3974 3975
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3976
		struct sk_security_struct *sksec = sk->sk_security;
3977
		struct common_audit_data ad;
3978
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
3979 3980 3981
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3982
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993

		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;
		}

3994 3995 3996 3997 3998 3999
		if (snum) {
			int low, high;

			inet_get_local_port_range(&low, &high);

			if (snum < max(PROT_SOCK, low) || snum > high) {
P
Paul Moore 已提交
4000 4001
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4002 4003
				if (err)
					goto out;
4004
				ad.type = LSM_AUDIT_DATA_NET;
4005 4006 4007
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4008 4009
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4010 4011 4012 4013
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4014
		}
4015

4016
		switch (sksec->sclass) {
4017
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4018 4019
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4020

4021
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4022 4023
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4024 4025 4026 4027 4028

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4029 4030 4031 4032
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4033

4034
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4035 4036
		if (err)
			goto out;
4037

4038
		ad.type = LSM_AUDIT_DATA_NET;
4039 4040 4041
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4042 4043

		if (family == PF_INET)
4044
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4045
		else
4046
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4047

4048 4049
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4050 4051 4052 4053 4054 4055 4056 4057 4058
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4059
	struct sock *sk = sock->sk;
4060
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4061 4062
	int err;

4063
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4064 4065 4066 4067
	if (err)
		return err;

	/*
J
James Morris 已提交
4068
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4069
	 */
4070 4071
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4072
		struct common_audit_data ad;
4073
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4074 4075 4076
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4077
		u32 sid, perm;
L
Linus Torvalds 已提交
4078 4079 4080

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4081
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4082 4083 4084 4085
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4086
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4087 4088 4089 4090
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4091
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4092 4093 4094
		if (err)
			goto out;

4095
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4096 4097
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4098
		ad.type = LSM_AUDIT_DATA_NET;
4099 4100 4101
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4102
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4103 4104 4105 4106
		if (err)
			goto out;
	}

4107 4108
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4109 4110 4111 4112 4113 4114
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4115
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4116 4117 4118 4119 4120 4121 4122 4123
}

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

4124
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138
	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,
4139
				  int size)
L
Linus Torvalds 已提交
4140
{
4141
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4142 4143 4144 4145 4146
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4147
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4148 4149 4150 4151
}

static int selinux_socket_getsockname(struct socket *sock)
{
4152
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4153 4154 4155 4156
}

static int selinux_socket_getpeername(struct socket *sock)
{
4157
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4158 4159
}

4160
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4161
{
4162 4163
	int err;

4164
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4165 4166 4167 4168
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4169 4170 4171 4172 4173
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4174
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4175 4176 4177 4178
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4179
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4180 4181
}

4182 4183
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4184 4185
					      struct sock *newsk)
{
4186 4187
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4188
	struct sk_security_struct *sksec_new = newsk->sk_security;
4189
	struct common_audit_data ad;
4190
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4191 4192
	int err;

4193
	ad.type = LSM_AUDIT_DATA_NET;
4194 4195
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4196

4197 4198
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4199 4200 4201 4202 4203
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4204 4205 4206 4207 4208
	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;
4209

4210 4211 4212 4213
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4214 4215 4216 4217 4218
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4219 4220
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4221
	struct common_audit_data ad;
4222
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4223

4224
	ad.type = LSM_AUDIT_DATA_NET;
4225 4226
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4227

4228 4229
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4230 4231
}

4232 4233
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4234
				    struct common_audit_data *ad)
4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250 4251 4252 4253 4254
{
	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);
}

4255
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4256
				       u16 family)
4257
{
4258
	int err = 0;
4259 4260
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4261
	struct common_audit_data ad;
4262
	struct lsm_network_audit net = {0,};
4263 4264
	char *addrp;

4265
	ad.type = LSM_AUDIT_DATA_NET;
4266 4267 4268
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4269 4270 4271
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4272

4273
	if (selinux_secmark_enabled()) {
4274
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4275
				   PACKET__RECV, &ad);
4276 4277 4278
		if (err)
			return err;
	}
4279

4280 4281 4282 4283
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4284

4285 4286 4287 4288 4289
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4290
	int err;
4291
	struct sk_security_struct *sksec = sk->sk_security;
4292 4293
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4294
	struct common_audit_data ad;
4295
	struct lsm_network_audit net = {0,};
4296
	char *addrp;
4297 4298
	u8 secmark_active;
	u8 peerlbl_active;
4299 4300

	if (family != PF_INET && family != PF_INET6)
4301
		return 0;
4302 4303

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4304
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4305 4306
		family = PF_INET;

4307 4308 4309 4310
	/* 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. */
4311
	if (!selinux_policycap_netpeer)
4312 4313 4314
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4315
	peerlbl_active = selinux_peerlbl_enabled();
4316 4317 4318
	if (!secmark_active && !peerlbl_active)
		return 0;

4319
	ad.type = LSM_AUDIT_DATA_NET;
4320 4321 4322
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4323
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4324
	if (err)
4325
		return err;
4326

4327
	if (peerlbl_active) {
4328 4329 4330
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4331 4332
		if (err)
			return err;
4333
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4334
					       peer_sid, &ad);
4335 4336
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4337
			return err;
4338
		}
4339 4340
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4341 4342
		if (err)
			selinux_netlbl_err(skb, err, 0);
4343 4344
	}

4345
	if (secmark_active) {
4346 4347 4348 4349 4350 4351
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4352
	return err;
L
Linus Torvalds 已提交
4353 4354
}

C
Catherine Zhang 已提交
4355 4356
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4357 4358 4359 4360
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4361
	struct sk_security_struct *sksec = sock->sk->sk_security;
4362
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4363

4364 4365
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4366
		peer_sid = sksec->peer_sid;
4367 4368
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4369

C
Catherine Zhang 已提交
4370
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4371
	if (err)
4372
		return err;
L
Linus Torvalds 已提交
4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388

	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;
}

4389
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4390
{
4391
	u32 peer_secid = SECSID_NULL;
4392
	u16 family;
C
Catherine Zhang 已提交
4393

4394 4395 4396 4397 4398
	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)
4399 4400 4401 4402 4403
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4404
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4405
	else if (skb)
4406
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4407

4408
out:
4409
	*secid = peer_secid;
4410 4411 4412
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4413 4414
}

A
Al Viro 已提交
4415
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4416
{
4417 4418 4419 4420 4421 4422 4423 4424 4425 4426 4427 4428
	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
4429 4430 4431 4432
}

static void selinux_sk_free_security(struct sock *sk)
{
4433 4434 4435 4436 4437
	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
4438 4439
}

4440
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4441
{
4442 4443
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4444

4445 4446 4447
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4448

4449
	selinux_netlbl_sk_security_reset(newsksec);
4450 4451
}

V
Venkat Yekkirala 已提交
4452
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4453
{
4454
	if (!sk)
V
Venkat Yekkirala 已提交
4455
		*secid = SECINITSID_ANY_SOCKET;
4456 4457
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4458

V
Venkat Yekkirala 已提交
4459
		*secid = sksec->sid;
4460
	}
4461 4462
}

4463
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4464 4465 4466 4467
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4468 4469 4470
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4471
	sksec->sclass = isec->sclass;
4472 4473
}

4474 4475
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4476 4477 4478
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4479
	u16 family = req->rsk_ops->family;
4480
	u32 connsid;
4481 4482
	u32 peersid;

4483
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4484 4485
	if (err)
		return err;
4486 4487 4488 4489 4490
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4491

4492
	return selinux_netlbl_inet_conn_request(req, family);
4493 4494
}

4495 4496
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4497 4498 4499 4500
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4501
	newsksec->peer_sid = req->peer_secid;
4502 4503 4504 4505
	/* 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. */
4506

P
Paul Moore 已提交
4507 4508
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4509
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4510 4511
}

4512
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4513
{
4514
	u16 family = sk->sk_family;
4515 4516
	struct sk_security_struct *sksec = sk->sk_security;

4517 4518 4519 4520 4521
	/* 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);
4522 4523
}

4524 4525 4526 4527 4528
static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
	skb_set_owner_w(skb, sk);
}

4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549
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);
}

4550 4551
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4552
{
4553
	fl->flowi_secid = req->secid;
4554 4555
}

4556 4557 4558 4559 4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573
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);
}

4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588
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);
}

4589
static int selinux_tun_dev_attach_queue(void *security)
4590
{
4591 4592 4593 4594 4595 4596 4597 4598 4599
	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;
4600 4601 4602 4603 4604 4605 4606 4607 4608
	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 */

4609
	sksec->sid = tunsec->sid;
4610
	sksec->sclass = SECCLASS_TUN_SOCKET;
4611 4612

	return 0;
4613 4614
}

4615
static int selinux_tun_dev_open(void *security)
4616
{
4617
	struct tun_security_struct *tunsec = security;
4618 4619 4620
	u32 sid = current_sid();
	int err;

4621
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4622 4623 4624 4625 4626 4627 4628
			   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;
4629
	tunsec->sid = sid;
4630 4631 4632 4633

	return 0;
}

L
Linus Torvalds 已提交
4634 4635 4636 4637 4638
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4639
	struct sk_security_struct *sksec = sk->sk_security;
4640

4641
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
4642 4643 4644
		err = -EINVAL;
		goto out;
	}
4645
	nlh = nlmsg_hdr(skb);
4646

4647
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4648 4649
	if (err) {
		if (err == -EINVAL) {
4650
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4651 4652
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4653
				  nlh->nlmsg_type, sksec->sclass);
4654
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4655 4656 4657 4658 4659 4660 4661 4662 4663
				err = 0;
		}

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

4664
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4665 4666 4667 4668 4669 4670
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4671 4672
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4673
{
4674
	int err;
4675 4676
	char *addrp;
	u32 peer_sid;
4677
	struct common_audit_data ad;
4678
	struct lsm_network_audit net = {0,};
4679
	u8 secmark_active;
4680
	u8 netlbl_active;
4681
	u8 peerlbl_active;
4682

4683 4684
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4685

4686
	secmark_active = selinux_secmark_enabled();
4687
	netlbl_active = netlbl_enabled();
4688
	peerlbl_active = selinux_peerlbl_enabled();
4689 4690
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4691

4692 4693 4694
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4695
	ad.type = LSM_AUDIT_DATA_NET;
4696 4697 4698
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4699 4700 4701
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4702 4703 4704 4705 4706
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4707
			return NF_DROP;
4708 4709
		}
	}
4710 4711 4712 4713 4714 4715

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

4716 4717 4718 4719 4720 4721 4722 4723
	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;

4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746
	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET);
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
static unsigned int selinux_ipv6_forward(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	return selinux_ip_forward(skb, in->ifindex, PF_INET6);
}
#endif	/* IPV6 */

4747 4748 4749
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
4750
	struct sock *sk;
4751 4752 4753 4754 4755 4756 4757 4758
	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 */
4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779
	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;
4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

static unsigned int selinux_ipv4_output(unsigned int hooknum,
					struct sk_buff *skb,
					const struct net_device *in,
					const struct net_device *out,
					int (*okfn)(struct sk_buff *))
{
	return selinux_ip_output(skb, PF_INET);
}

4798 4799
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4800
						u16 family)
4801 4802 4803
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4804
	struct common_audit_data ad;
4805
	struct lsm_network_audit net = {0,};
4806 4807
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4808

4809 4810 4811 4812
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4813
	ad.type = LSM_AUDIT_DATA_NET;
4814 4815 4816
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4817 4818 4819
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4820
	if (selinux_secmark_enabled())
4821
		if (avc_has_perm(sksec->sid, skb->secmark,
4822
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4823
			return NF_DROP_ERR(-ECONNREFUSED);
4824

4825 4826
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4827 4828

	return NF_ACCEPT;
4829 4830
}

4831 4832
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4833
{
4834 4835
	u32 secmark_perm;
	u32 peer_sid;
4836
	struct sock *sk;
4837
	struct common_audit_data ad;
4838
	struct lsm_network_audit net = {0,};
4839 4840 4841
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4842

4843 4844 4845 4846
	/* 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. */
4847
	if (!selinux_policycap_netpeer)
4848
		return selinux_ip_postroute_compat(skb, ifindex, family);
4849 4850 4851 4852 4853 4854 4855 4856

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

	sk = skb->sk;

4857
#ifdef CONFIG_XFRM
4858 4859 4860 4861 4862
	/* 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
4863 4864 4865 4866 4867 4868 4869 4870
	 *       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))
4871
		return NF_ACCEPT;
4872
#endif
4873

4874
	if (sk == NULL) {
4875 4876 4877 4878
		/* 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. */
4879 4880
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4881
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4882
				return NF_DROP;
4883 4884
		} else {
			secmark_perm = PACKET__SEND;
4885
			peer_sid = SECINITSID_KERNEL;
4886
		}
4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900
	} 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;
4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919
		/* 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);
			}
		}
4920 4921 4922
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
4923
	} else {
4924 4925
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
4926 4927 4928 4929
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4930

4931
	ad.type = LSM_AUDIT_DATA_NET;
4932 4933 4934
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
4935
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4936
		return NF_DROP;
4937

4938 4939 4940
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4941
			return NF_DROP_ERR(-ECONNREFUSED);
4942 4943 4944 4945 4946 4947

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4948
			return NF_DROP;
4949 4950
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4951
			return NF_DROP_ERR(-ECONNREFUSED);
4952 4953

		if (sel_netnode_sid(addrp, family, &node_sid))
4954
			return NF_DROP;
4955 4956
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4957
			return NF_DROP_ERR(-ECONNREFUSED);
4958
	}
4959

4960
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4961 4962
}

4963 4964 4965 4966 4967
static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4968
{
4969
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4970 4971 4972
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4973 4974 4975 4976 4977
static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
					   struct sk_buff *skb,
					   const struct net_device *in,
					   const struct net_device *out,
					   int (*okfn)(struct sk_buff *))
L
Linus Torvalds 已提交
4978
{
4979
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4980 4981 4982 4983 4984 4985 4986 4987 4988
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4989
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4990 4991 4992
	if (err)
		return err;

4993
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4994 4995 4996 4997 4998 4999 5000
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
5001
	u32 sid;
L
Linus Torvalds 已提交
5002

J
James Morris 已提交
5003
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5004 5005 5006
	if (!isec)
		return -ENOMEM;

5007
	sid = task_sid(task);
L
Linus Torvalds 已提交
5008
	isec->sclass = sclass;
5009
	isec->sid = sid;
L
Linus Torvalds 已提交
5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025
	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
5026
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044
	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,
5045
			u32 perms)
L
Linus Torvalds 已提交
5046 5047
{
	struct ipc_security_struct *isec;
5048
	struct common_audit_data ad;
5049
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5050 5051 5052

	isec = ipc_perms->security;

5053
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5054 5055
	ad.u.ipc_id = ipc_perms->key;

5056
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072
}

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;
5073
	struct common_audit_data ad;
5074
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5075 5076 5077 5078 5079 5080 5081 5082
	int rc;

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

	isec = msq->q_perm.security;

5083
	ad.type = LSM_AUDIT_DATA_IPC;
5084
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5085

5086
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099 5100 5101 5102
			  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;
5103
	struct common_audit_data ad;
5104
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5105 5106 5107

	isec = msq->q_perm.security;

5108
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5109 5110
	ad.u.ipc_id = msq->q_perm.key;

5111
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5112 5113 5114 5115 5116 5117 5118 5119
			    MSGQ__ASSOCIATE, &ad);
}

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

5120
	switch (cmd) {
L
Linus Torvalds 已提交
5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138
	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;
	}

5139
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5140 5141 5142 5143 5144 5145 5146
	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;
5147
	struct common_audit_data ad;
5148
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161
	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
		 */
5162
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5163
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5164 5165 5166 5167
		if (rc)
			return rc;
	}

5168
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5169 5170 5171
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5172
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5173 5174 5175
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5176 5177
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5178 5179
	if (!rc)
		/* Can the message be put in the queue? */
5180 5181
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5182 5183 5184 5185 5186 5187 5188 5189 5190 5191

	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;
5192
	struct common_audit_data ad;
5193
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5194 5195 5196 5197 5198
	int rc;

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

5199
	ad.type = LSM_AUDIT_DATA_IPC;
5200
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5201

5202
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5203 5204
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5205
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5206 5207 5208 5209 5210 5211 5212 5213
				  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;
5214
	struct common_audit_data ad;
5215
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5216 5217 5218 5219 5220 5221 5222 5223
	int rc;

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

	isec = shp->shm_perm.security;

5224
	ad.type = LSM_AUDIT_DATA_IPC;
5225
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5226

5227
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243
			  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;
5244
	struct common_audit_data ad;
5245
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5246 5247 5248

	isec = shp->shm_perm.security;

5249
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5250 5251
	ad.u.ipc_id = shp->shm_perm.key;

5252
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5253 5254 5255 5256 5257 5258 5259 5260 5261
			    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;

5262
	switch (cmd) {
L
Linus Torvalds 已提交
5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284
	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;
	}

5285
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298
	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;

5299
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5300 5301 5302 5303 5304 5305
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5306
	struct common_audit_data ad;
5307
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5308 5309 5310 5311 5312 5313 5314 5315
	int rc;

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

	isec = sma->sem_perm.security;

5316
	ad.type = LSM_AUDIT_DATA_IPC;
5317
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5318

5319
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335
			  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;
5336
	struct common_audit_data ad;
5337
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5338 5339 5340

	isec = sma->sem_perm.security;

5341
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5342 5343
	ad.u.ipc_id = sma->sem_perm.key;

5344
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5345 5346 5347 5348 5349 5350 5351 5352 5353
			    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;

5354
	switch (cmd) {
L
Linus Torvalds 已提交
5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385
	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;
	}

5386
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399
	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;

5400
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415
}

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;

5416
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5417 5418
}

5419 5420 5421 5422 5423 5424
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5425
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5426 5427 5428 5429 5430 5431
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5432
			       char *name, char **value)
L
Linus Torvalds 已提交
5433
{
5434
	const struct task_security_struct *__tsec;
5435
	u32 sid;
L
Linus Torvalds 已提交
5436
	int error;
5437
	unsigned len;
L
Linus Torvalds 已提交
5438 5439

	if (current != p) {
5440
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5441 5442 5443 5444
		if (error)
			return error;
	}

5445 5446
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5447 5448

	if (!strcmp(name, "current"))
5449
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5450
	else if (!strcmp(name, "prev"))
5451
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5452
	else if (!strcmp(name, "exec"))
5453
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5454
	else if (!strcmp(name, "fscreate"))
5455
		sid = __tsec->create_sid;
5456
	else if (!strcmp(name, "keycreate"))
5457
		sid = __tsec->keycreate_sid;
5458
	else if (!strcmp(name, "sockcreate"))
5459
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5460
	else
5461 5462
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5463 5464 5465 5466

	if (!sid)
		return 0;

5467 5468 5469 5470
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5471 5472 5473 5474

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5475 5476 5477 5478 5479 5480
}

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
5481
	struct task_struct *tracer;
D
David Howells 已提交
5482 5483
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498
	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"))
5499
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5500
	else if (!strcmp(name, "fscreate"))
5501
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5502
	else if (!strcmp(name, "keycreate"))
5503
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5504
	else if (!strcmp(name, "sockcreate"))
5505
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5506
	else if (!strcmp(name, "current"))
5507
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
	if (size && str[1] && str[1] != '\n') {
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
		error = security_context_to_sid(value, size, &sid);
5520
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535
			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);

5536
				return error;
5537
			}
5538 5539 5540
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5541 5542 5543 5544
		if (error)
			return error;
	}

D
David Howells 已提交
5545 5546 5547 5548
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5549 5550 5551
	/* 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
5552
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5553 5554
	   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
5555 5556
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5557
		tsec->exec_sid = sid;
D
David Howells 已提交
5558
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5559
		tsec->create_sid = sid;
D
David Howells 已提交
5560
	} else if (!strcmp(name, "keycreate")) {
5561 5562
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5563
			goto abort_change;
5564
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5565
	} else if (!strcmp(name, "sockcreate")) {
5566
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5567 5568
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5569
		if (sid == 0)
D
David Howells 已提交
5570 5571 5572 5573
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5574
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5575 5576 5577
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5578
		}
L
Linus Torvalds 已提交
5579 5580 5581

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5582
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5583
		if (error)
D
David Howells 已提交
5584
			goto abort_change;
L
Linus Torvalds 已提交
5585 5586 5587

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5588
		ptsid = 0;
L
Linus Torvalds 已提交
5589
		task_lock(p);
5590
		tracer = ptrace_parent(p);
D
David Howells 已提交
5591 5592 5593 5594 5595 5596 5597
		if (tracer)
			ptsid = task_sid(tracer);
		task_unlock(p);

		if (tracer) {
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
5598
			if (error)
D
David Howells 已提交
5599
				goto abort_change;
L
Linus Torvalds 已提交
5600 5601
		}

D
David Howells 已提交
5602 5603 5604 5605 5606 5607 5608
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5609
	return size;
D
David Howells 已提交
5610 5611 5612 5613

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5614 5615
}

5616 5617 5618 5619 5620
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

5621 5622 5623 5624 5625
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5626
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5627 5628 5629 5630
{
	return security_context_to_sid(secdata, seclen, secid);
}

5631 5632
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5633
	kfree(secdata);
5634 5635
}

5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661
/*
 *	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;
}
5662 5663
#ifdef CONFIG_KEYS

D
David Howells 已提交
5664
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5665
			     unsigned long flags)
5666
{
D
David Howells 已提交
5667
	const struct task_security_struct *tsec;
5668 5669 5670 5671 5672 5673
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5674 5675 5676
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5677
	else
D
David Howells 已提交
5678
		ksec->sid = tsec->sid;
5679

5680
	k->security = ksec;
5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692
	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
5693 5694
				  const struct cred *cred,
				  key_perm_t perm)
5695 5696 5697
{
	struct key *key;
	struct key_security_struct *ksec;
5698
	u32 sid;
5699 5700 5701 5702 5703 5704 5705

	/* 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
5706
	sid = cred_sid(cred);
5707 5708 5709 5710 5711

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5712 5713
}

5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726 5727
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;
}

5728 5729
#endif

L
Linus Torvalds 已提交
5730
static struct security_operations selinux_ops = {
5731 5732
	.name =				"selinux",

5733
	.ptrace_access_check =		selinux_ptrace_access_check,
5734
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5735
	.capget =			selinux_capget,
D
David Howells 已提交
5736
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5737 5738 5739 5740 5741 5742 5743 5744
	.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,

5745 5746 5747
	.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
5748 5749 5750 5751 5752
	.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,
5753
	.sb_remount =			selinux_sb_remount,
5754
	.sb_kern_mount =		selinux_sb_kern_mount,
5755
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5756 5757 5758
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5759
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5760
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5761 5762
	.sb_parse_opts_str = 		selinux_parse_opts_str,

5763
	.dentry_init_security =		selinux_dentry_init_security,
L
Linus Torvalds 已提交
5764 5765 5766

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5767
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785
	.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,
5786 5787 5788
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5789
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5790 5791 5792 5793 5794

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
5795 5796
	.mmap_file =			selinux_mmap_file,
	.mmap_addr =			selinux_mmap_addr,
L
Linus Torvalds 已提交
5797 5798 5799 5800 5801 5802 5803
	.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,

5804
	.file_open =			selinux_file_open,
5805

L
Linus Torvalds 已提交
5806
	.task_create =			selinux_task_create,
5807
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5808
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5809
	.cred_prepare =			selinux_cred_prepare,
5810
	.cred_transfer =		selinux_cred_transfer,
5811 5812
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5813
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5814 5815
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5816
	.task_getsid =			selinux_task_getsid,
5817
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5818
	.task_setnice =			selinux_task_setnice,
5819
	.task_setioprio =		selinux_task_setioprio,
5820
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5821 5822 5823
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5824
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5825 5826
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5827
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5828 5829

	.ipc_permission =		selinux_ipc_permission,
5830
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844 5845 5846 5847

	.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,

5848 5849
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5850 5851 5852 5853
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5854
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5855

5856 5857
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5858

5859
	.ismaclabel =			selinux_ismaclabel,
5860
	.secid_to_secctx =		selinux_secid_to_secctx,
5861
	.secctx_to_secid =		selinux_secctx_to_secid,
5862
	.release_secctx =		selinux_release_secctx,
5863 5864 5865
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5866

5867
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883
	.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
5884 5885
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5886 5887
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5888
	.sk_clone_security =		selinux_sk_clone_security,
5889
	.sk_getsecid =			selinux_sk_getsecid,
5890 5891 5892
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5893
	.inet_conn_established =	selinux_inet_conn_established,
5894 5895 5896
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5897
	.req_classify_flow =		selinux_req_classify_flow,
5898 5899
	.tun_dev_alloc_security =	selinux_tun_dev_alloc_security,
	.tun_dev_free_security =	selinux_tun_dev_free_security,
5900
	.tun_dev_create =		selinux_tun_dev_create,
5901
	.tun_dev_attach_queue =		selinux_tun_dev_attach_queue,
5902
	.tun_dev_attach =		selinux_tun_dev_attach,
5903
	.tun_dev_open =			selinux_tun_dev_open,
5904
	.skb_owned_by =			selinux_skb_owned_by,
5905 5906 5907 5908 5909

#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
5910
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5911 5912
	.xfrm_state_alloc =		selinux_xfrm_state_alloc,
	.xfrm_state_alloc_acquire =	selinux_xfrm_state_alloc_acquire,
5913
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5914
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5915
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5916 5917
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5918
#endif
5919 5920

#ifdef CONFIG_KEYS
5921 5922 5923
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5924
	.key_getsecurity =		selinux_key_getsecurity,
5925
#endif
5926 5927 5928 5929 5930 5931 5932

#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
5933 5934 5935 5936
};

static __init int selinux_init(void)
{
5937 5938 5939 5940 5941
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5942 5943 5944 5945 5946 5947 5948 5949
	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
5950
	cred_init_security();
L
Linus Torvalds 已提交
5951

5952 5953
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5954 5955
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5956
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5957 5958
	avc_init();

5959
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5960 5961
		panic("SELinux: Unable to register with kernel.\n");

5962
	if (selinux_enforcing)
5963
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5964
	else
5965
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5966

L
Linus Torvalds 已提交
5967 5968 5969
	return 0;
}

5970 5971 5972 5973 5974
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5975 5976
void selinux_complete_init(void)
{
5977
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5978 5979

	/* Set up any superblocks initialized prior to the policy load. */
5980
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5981
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5982 5983 5984 5985 5986 5987
}

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

5988
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5989

5990 5991 5992 5993
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
5994
		.pf =		NFPROTO_IPV4,
5995 5996 5997 5998 5999 6000
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
6001
		.pf =		NFPROTO_IPV4,
6002 6003
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6004 6005 6006 6007
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
6008
		.pf =		NFPROTO_IPV4,
6009 6010
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6011
	}
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};

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

6016 6017 6018 6019
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
6020
		.pf =		NFPROTO_IPV6,
6021 6022 6023 6024 6025 6026
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
6027
		.pf =		NFPROTO_IPV6,
6028 6029 6030
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
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};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
6041 6042 6043

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

6044 6045 6046
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6049 6050 6051
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
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6052
#endif	/* IPV6 */
6053

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out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6063
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
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6064

6065
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
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6066
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6067
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
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#endif	/* IPV6 */
}
#endif

6072
#else /* CONFIG_NETFILTER */
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#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6078
#endif /* CONFIG_NETFILTER */
L
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6079 6080

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6081 6082
static int selinux_disabled;

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int selinux_disable(void)
{
	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

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

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

	selinux_disabled = 1;
6098
	selinux_enabled = 0;
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6099

6100
	reset_security_ops();
L
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6101

6102 6103 6104
	/* Try to destroy the avc node cache */
	avc_disable();

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

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif