hooks.c 143.0 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/tcp.h>		/* struct or_callable used in sock_rcv_skb */
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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 */
#include <linux/netlink.h>
#include <linux/tcp.h>
#include <linux/udp.h>
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#include <linux/dccp.h>
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#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
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#include <linux/string.h>
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#include <linux/selinux.h>
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#include <linux/mutex.h>
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#include <linux/posix-timers.h>
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#include <linux/syslog.h>
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#include <linux/user_namespace.h>
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#include <linux/export.h>
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#include <linux/msg.h>
#include <linux/shm.h>
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#include "avc.h"
#include "objsec.h"
#include "netif.h"
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#include "netnode.h"
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#include "netport.h"
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#include "xfrm.h"
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#include "netlabel.h"
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#include "audit.h"
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#include "avc_ss.h"
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#define NUM_SEL_MNT_OPTS 5
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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
 * enabled, false (0) if SECMARK is disabled.
 *
 */
static int selinux_secmark_enabled(void)
{
	return (atomic_read(&selinux_secmark_refcount) > 0);
}

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

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

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

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

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

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

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

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

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

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

	return 0;
}

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[6] = {
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	"uses xattr",
	"uses transition SIDs",
	"uses task SIDs",
	"uses genfs_contexts",
	"not configured for labeling",
	"uses mountpoint labeling",
};

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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};

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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 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) {
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
			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 "
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
			goto out;
		}
	}
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	sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
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	if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
		       sb->s_id, sb->s_type->name);
	else
		printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
		       sb->s_id, sb->s_type->name,
		       labeling_behaviors[sbsec->behavior-1]);
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	if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
	    sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
	    sbsec->behavior == SECURITY_FS_USE_NONE ||
	    sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
		sbsec->flags &= ~SE_SBLABELSUPP;

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

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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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	tmp = sbsec->flags & SE_MNTMASK;
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	/* count the number of mount options for this sb */
	for (i = 0; i < 8; i++) {
		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 */
	if (sbsec->flags & SE_SBLABELSUPP)
		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 & SE_SBLABELSUPP) {
		opts->mnt_opts[i] = NULL;
		opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
	}
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	BUG_ON(i != opts->num_mnt_opts);
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	return 0;

out_free:
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	security_free_mnt_opts(opts);
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	return rc;
}
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static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
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	char mnt_flags = sbsec->flags & SE_MNTMASK;

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	/* check if the old mount command had the same options */
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	if (sbsec->flags & SE_SBINITIALIZED)
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		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
	 */
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	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
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			return 1;
	return 0;
}
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/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
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static int selinux_set_mnt_opts(struct super_block *sb,
				struct security_mnt_opts *opts)
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{
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	const struct cred *cred = current_cred();
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	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	const char *name = sb->s_type->name;
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	struct inode *inode = sbsec->sb->s_root->d_inode;
	struct inode_security_struct *root_isec = inode->i_security;
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	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
564 565 566
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
567 568 569 570 571 572 573 574 575 576 577

	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
578 579
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
580
		goto out;
581
	}
L
Linus Torvalds 已提交
582

583 584 585 586 587 588 589 590 591 592 593
	/*
	 * 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)
	 */
594
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
595
	    && (num_opts == 0))
596
		goto out;
597

598 599 600 601 602 603 604
	/*
	 * 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;
605 606 607

		if (flags[i] == SE_SBLABELSUPP)
			continue;
608 609
		rc = security_context_to_sid(mount_options[i],
					     strlen(mount_options[i]), &sid);
L
Linus Torvalds 已提交
610 611 612
		if (rc) {
			printk(KERN_WARNING "SELinux: security_context_to_sid"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657
			       mount_options[i], sb->s_id, name, rc);
			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
658
		}
659 660
	}

661
	if (sbsec->flags & SE_SBINITIALIZED) {
662
		/* previously mounted with options, but not on this attempt? */
663
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
664 665 666 667 668
			goto out_double_mount;
		rc = 0;
		goto out;
	}

669
	if (strcmp(sb->s_type->name, "proc") == 0)
670
		sbsec->flags |= SE_SBPROC;
671 672

	/* Determine the labeling behavior to use for this filesystem type. */
673
	rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
674 675
	if (rc) {
		printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
676
		       __func__, sb->s_type->name, rc);
677 678
		goto out;
	}
L
Linus Torvalds 已提交
679

680 681
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
682
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
683
		if (rc)
684
			goto out;
L
Linus Torvalds 已提交
685

686
		sbsec->sid = fscontext_sid;
687 688 689 690 691 692 693
	}

	/*
	 * 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.
	 */
694 695
	if (context_sid) {
		if (!fscontext_sid) {
696 697
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
698
			if (rc)
699 700
				goto out;
			sbsec->sid = context_sid;
701
		} else {
702 703
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
704
			if (rc)
705
				goto out;
706
		}
707 708
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
709

710
		sbsec->mntpoint_sid = context_sid;
711
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
712 713
	}

714
	if (rootcontext_sid) {
715 716
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
717
		if (rc)
718
			goto out;
719

720 721
		root_isec->sid = rootcontext_sid;
		root_isec->initialized = 1;
722 723
	}

724 725 726 727 728 729
	if (defcontext_sid) {
		if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
730 731
		}

732 733
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
734
							     sbsec, cred);
735 736 737
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
738

739
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
740 741
	}

742
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
743
out:
744
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
745
	return rc;
746 747 748 749 750
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
	goto out;
L
Linus Torvalds 已提交
751 752
}

753 754
static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
					struct super_block *newsb)
L
Linus Torvalds 已提交
755
{
756 757
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
758

759 760 761
	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
762

763 764
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
765
	 * mount options.  thus we can safely deal with this superblock later
766
	 */
767
	if (!ss_initialized)
768
		return;
769 770

	/* how can we clone if the old one wasn't set up?? */
771
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
772

773
	/* if fs is reusing a sb, just let its options stand... */
774
	if (newsbsec->flags & SE_SBINITIALIZED)
775 776
		return;

777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795
	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
796
	}
797 798 799 800 801
	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
802

803
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
804 805
	}

806 807 808 809
	sb_finish_set_opts(newsb);
	mutex_unlock(&newsbsec->lock);
}

810 811
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
812
{
813
	char *p;
814 815
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
816
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
817

818
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
819

820 821 822 823
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
824

825 826
		if (!*p)
			continue;
L
Linus Torvalds 已提交
827

828
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
829

830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
		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;
882 883
		case Opt_labelsupport:
			break;
884 885 886 887
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
888 889 890

		}
	}
891

892 893 894 895 896 897 898 899 900 901 902
	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;
	}

903
	if (fscontext) {
904 905
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
906 907
	}
	if (context) {
908 909
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
910 911
	}
	if (rootcontext) {
912 913
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
914 915
	}
	if (defcontext) {
916 917
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
918 919
	}

920 921 922
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

923 924 925 926 927
out_err:
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
928 929
	return rc;
}
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
/*
 * 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:
	rc = selinux_set_mnt_opts(sb, &opts);

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
957

A
Adrian Bunk 已提交
958 959
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
960 961 962 963 964
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
965 966 967 968 969 970
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
971 972 973 974 975 976 977 978 979 980 981 982 983 984

		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;
985 986 987 988
		case SE_SBLABELSUPP:
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
989 990
		default:
			BUG();
991
			return;
992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009
		};
		/* 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);
1010 1011 1012 1013
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1014
		return rc;
1015
	}
1016 1017 1018 1019 1020 1021 1022 1023

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046
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;
}

1047 1048 1049 1050 1051 1052 1053 1054 1055 1056
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
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072
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:
1073 1074 1075 1076
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1077
		case SOCK_DGRAM:
1078 1079 1080 1081
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1082 1083
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1084
		default:
L
Linus Torvalds 已提交
1085 1086 1087 1088 1089 1090 1091 1092 1093
			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;
1094
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107
			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;
1108 1109
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
L
Linus Torvalds 已提交
1110 1111 1112 1113 1114 1115 1116
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1117 1118
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1119 1120 1121 1122 1123 1124
	}

	return SECCLASS_SOCKET;
}

#ifdef CONFIG_PROC_FS
1125
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1126 1127 1128
				u16 tclass,
				u32 *sid)
{
1129 1130
	int rc;
	char *buffer, *path;
L
Linus Torvalds 已提交
1131

1132
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1133 1134 1135
	if (!buffer)
		return -ENOMEM;

1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147
	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
1148 1149 1150 1151 1152
	}
	free_page((unsigned long)buffer);
	return rc;
}
#else
1153
static int selinux_proc_get_sid(struct dentry *dentry,
L
Linus Torvalds 已提交
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175
				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;

1176
	mutex_lock(&isec->lock);
L
Linus Torvalds 已提交
1177
	if (isec->initialized)
1178
		goto out_unlock;
L
Linus Torvalds 已提交
1179 1180

	sbsec = inode->i_sb->s_security;
1181
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1182 1183 1184 1185 1186 1187 1188
		/* 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);
1189
		goto out_unlock;
L
Linus Torvalds 已提交
1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
	}

	switch (sbsec->behavior) {
	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) {
1209 1210 1211 1212 1213 1214 1215 1216 1217
			/*
			 * 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.
			 */
1218
			goto out_unlock;
L
Linus Torvalds 已提交
1219 1220 1221
		}

		len = INITCONTEXTLEN;
1222
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1223 1224 1225
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1226
			goto out_unlock;
L
Linus Torvalds 已提交
1227
		}
1228
		context[len] = '\0';
L
Linus Torvalds 已提交
1229 1230 1231
		rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
					   context, len);
		if (rc == -ERANGE) {
1232 1233
			kfree(context);

L
Linus Torvalds 已提交
1234 1235 1236 1237 1238
			/* 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);
1239
				goto out_unlock;
L
Linus Torvalds 已提交
1240 1241
			}
			len = rc;
1242
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1243 1244 1245
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1246
				goto out_unlock;
L
Linus Torvalds 已提交
1247
			}
1248
			context[len] = '\0';
L
Linus Torvalds 已提交
1249 1250 1251 1252 1253 1254 1255
			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
1256
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1257
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1258 1259
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1260
				goto out_unlock;
L
Linus Torvalds 已提交
1261 1262 1263 1264 1265
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1266
			rc = security_context_to_sid_default(context, rc, &sid,
1267 1268
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1269
			if (rc) {
1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282
				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
1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
				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);
1301 1302
		rc = security_transition_sid(isec->task_sid, sbsec->sid,
					     isec->sclass, NULL, &sid);
L
Linus Torvalds 已提交
1303
		if (rc)
1304
			goto out_unlock;
L
Linus Torvalds 已提交
1305 1306
		isec->sid = sid;
		break;
1307 1308 1309
	case SECURITY_FS_USE_MNTPOINT:
		isec->sid = sbsec->mntpoint_sid;
		break;
L
Linus Torvalds 已提交
1310
	default:
1311
		/* Default to the fs superblock SID. */
L
Linus Torvalds 已提交
1312 1313
		isec->sid = sbsec->sid;

1314
		if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1315
			if (opt_dentry) {
L
Linus Torvalds 已提交
1316
				isec->sclass = inode_mode_to_security_class(inode->i_mode);
1317
				rc = selinux_proc_get_sid(opt_dentry,
L
Linus Torvalds 已提交
1318 1319 1320
							  isec->sclass,
							  &sid);
				if (rc)
1321
					goto out_unlock;
L
Linus Torvalds 已提交
1322 1323 1324 1325 1326 1327 1328 1329
				isec->sid = sid;
			}
		}
		break;
	}

	isec->initialized = 1;

1330 1331
out_unlock:
	mutex_unlock(&isec->lock);
L
Linus Torvalds 已提交
1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364
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
1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377
/*
 * 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);
}

1378
/*
1379
 * Check permission between a pair of tasks, e.g. signal checks,
1380 1381
 * fork check, ptrace check, etc.
 * tsk1 is the actor and tsk2 is the target
1382
 * - this uses the default subjective creds of tsk1
1383 1384 1385
 */
static int task_has_perm(const struct task_struct *tsk1,
			 const struct task_struct *tsk2,
L
Linus Torvalds 已提交
1386 1387
			 u32 perms)
{
1388 1389
	const struct task_security_struct *__tsec1, *__tsec2;
	u32 sid1, sid2;
L
Linus Torvalds 已提交
1390

1391 1392 1393 1394 1395
	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
1396 1397
}

1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413
/*
 * 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);
}

1414 1415 1416 1417
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1418
/* Check whether a task is allowed to use a capability. */
1419
static int cred_has_capability(const struct cred *cred,
1420
			       int cap, int audit)
L
Linus Torvalds 已提交
1421
{
1422
	struct common_audit_data ad;
1423
	struct selinux_audit_data sad = {0,};
1424
	struct av_decision avd;
1425
	u16 sclass;
1426
	u32 sid = cred_sid(cred);
1427
	u32 av = CAP_TO_MASK(cap);
1428
	int rc;
L
Linus Torvalds 已提交
1429

1430
	COMMON_AUDIT_DATA_INIT(&ad, CAP);
1431
	ad.selinux_audit_data = &sad;
1432
	ad.tsk = current;
L
Linus Torvalds 已提交
1433 1434
	ad.u.cap = cap;

1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445
	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();
1446
		return -EINVAL;
1447
	}
1448

1449
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1450 1451 1452 1453 1454
	if (audit == SECURITY_CAP_AUDIT) {
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
		if (rc2)
			return rc2;
	}
1455
	return rc;
L
Linus Torvalds 已提交
1456 1457 1458 1459 1460 1461
}

/* Check whether a task is allowed to use a system operation. */
static int task_has_system(struct task_struct *tsk,
			   u32 perms)
{
1462
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
1463

1464
	return avc_has_perm(sid, SECINITSID_KERNEL,
L
Linus Torvalds 已提交
1465 1466 1467 1468 1469 1470
			    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). */
1471
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1472 1473
			  struct inode *inode,
			  u32 perms,
1474 1475
			  struct common_audit_data *adp,
			  unsigned flags)
L
Linus Torvalds 已提交
1476 1477
{
	struct inode_security_struct *isec;
1478
	u32 sid;
L
Linus Torvalds 已提交
1479

1480 1481
	validate_creds(cred);

1482
	if (unlikely(IS_PRIVATE(inode)))
1483 1484
		return 0;

1485
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1486 1487
	isec = inode->i_security;

1488
	return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
L
Linus Torvalds 已提交
1489 1490
}

1491 1492 1493 1494 1495 1496
static int inode_has_perm_noadp(const struct cred *cred,
				struct inode *inode,
				u32 perms,
				unsigned flags)
{
	struct common_audit_data ad;
1497
	struct selinux_audit_data sad = {0,};
1498 1499 1500

	COMMON_AUDIT_DATA_INIT(&ad, INODE);
	ad.u.inode = inode;
1501
	ad.selinux_audit_data = &sad;
1502 1503 1504
	return inode_has_perm(cred, inode, perms, &ad, flags);
}

L
Linus Torvalds 已提交
1505 1506 1507
/* 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. */
1508
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1509 1510 1511 1512
				  struct dentry *dentry,
				  u32 av)
{
	struct inode *inode = dentry->d_inode;
1513
	struct common_audit_data ad;
1514
	struct selinux_audit_data sad = {0,};
1515

E
Eric Paris 已提交
1516 1517
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
1518
	ad.selinux_audit_data = &sad;
E
Eric Paris 已提交
1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530
	return inode_has_perm(cred, inode, av, &ad, 0);
}

/* 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;
1531
	struct selinux_audit_data sad = {0,};
E
Eric Paris 已提交
1532

1533
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
E
Eric Paris 已提交
1534
	ad.u.path = *path;
1535
	ad.selinux_audit_data = &sad;
1536
	return inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546
}

/* 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. */
1547 1548 1549
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1550 1551
{
	struct file_security_struct *fsec = file->f_security;
1552
	struct inode *inode = file->f_path.dentry->d_inode;
1553
	struct common_audit_data ad;
1554
	struct selinux_audit_data sad = {0,};
1555
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1556 1557
	int rc;

1558 1559
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
	ad.u.path = file->f_path;
1560
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
1561

1562 1563
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1564 1565 1566 1567
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1568
			goto out;
L
Linus Torvalds 已提交
1569 1570 1571
	}

	/* av is zero if only checking access to the descriptor. */
1572
	rc = 0;
L
Linus Torvalds 已提交
1573
	if (av)
1574
		rc = inode_has_perm(cred, inode, av, &ad, 0);
L
Linus Torvalds 已提交
1575

1576 1577
out:
	return rc;
L
Linus Torvalds 已提交
1578 1579 1580 1581 1582 1583 1584
}

/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1585
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1586 1587
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1588
	u32 sid, newsid;
1589
	struct common_audit_data ad;
1590
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
1591 1592 1593 1594 1595
	int rc;

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

1596 1597 1598
	sid = tsec->sid;
	newsid = tsec->create_sid;

1599 1600
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
1601
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
1602

1603
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1604 1605 1606 1607 1608
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1609
	if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1610 1611
		rc = security_transition_sid(sid, dsec->sid, tclass,
					     &dentry->d_name, &newsid);
L
Linus Torvalds 已提交
1612 1613 1614 1615
		if (rc)
			return rc;
	}

1616
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1617 1618 1619 1620 1621 1622 1623 1624
	if (rc)
		return rc;

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

1625 1626 1627 1628
/* Check whether a task can create a key. */
static int may_create_key(u32 ksid,
			  struct task_struct *ctx)
{
1629
	u32 sid = task_sid(ctx);
1630

1631
	return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1632 1633
}

1634 1635 1636
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1637 1638 1639 1640 1641 1642 1643 1644

/* 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;
1645
	struct common_audit_data ad;
1646
	struct selinux_audit_data sad = {0,};
1647
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1648 1649 1650 1651 1652 1653
	u32 av;
	int rc;

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

1654 1655
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
	ad.u.dentry = dentry;
1656
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
1657 1658 1659

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1660
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674
	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
1675 1676
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1677 1678 1679
		return 0;
	}

1680
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1681 1682 1683 1684 1685 1686 1687 1688 1689
	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;
1690
	struct common_audit_data ad;
1691
	struct selinux_audit_data sad = {0,};
1692
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1693 1694 1695 1696 1697 1698 1699 1700 1701
	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;

1702
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1703
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
1704

1705
	ad.u.dentry = old_dentry;
1706
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1707 1708 1709
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1710
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1711 1712 1713 1714
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1715
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

1721
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
1722 1723 1724
	av = DIR__ADD_NAME | DIR__SEARCH;
	if (new_dentry->d_inode)
		av |= DIR__REMOVE_NAME;
1725
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1726 1727 1728 1729 1730
	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);
1731
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
1732 1733 1734 1735 1736 1737 1738 1739 1740 1741
				  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. */
1742
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1743 1744
			       struct super_block *sb,
			       u32 perms,
1745
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
1746 1747
{
	struct superblock_security_struct *sbsec;
1748
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1749 1750

	sbsec = sb->s_security;
1751
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
1752 1753 1754 1755 1756 1757 1758
}

/* 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
1759
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781
		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;
}

1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804
/* 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
1805
/*
1806
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
1807 1808
 * open permission.
 */
1809
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
1810
{
1811
	u32 av = file_to_av(file);
E
Eric Paris 已提交
1812

1813 1814 1815
	if (selinux_policycap_openperm)
		av |= FILE__OPEN;

E
Eric Paris 已提交
1816 1817 1818
	return av;
}

L
Linus Torvalds 已提交
1819 1820
/* Hook functions begin here. */

1821
static int selinux_ptrace_access_check(struct task_struct *child,
1822
				     unsigned int mode)
L
Linus Torvalds 已提交
1823 1824 1825
{
	int rc;

1826
	rc = cap_ptrace_access_check(child, mode);
L
Linus Torvalds 已提交
1827 1828 1829
	if (rc)
		return rc;

1830
	if (mode & PTRACE_MODE_READ) {
1831 1832 1833
		u32 sid = current_sid();
		u32 csid = task_sid(child);
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1834 1835
	}

1836
	return current_has_perm(child, PROCESS__PTRACE);
1837 1838 1839 1840 1841 1842
}

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

1843
	rc = cap_ptrace_traceme(parent);
1844 1845 1846 1847
	if (rc)
		return rc;

	return task_has_perm(parent, current, PROCESS__PTRACE);
L
Linus Torvalds 已提交
1848 1849 1850
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1851
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
1852 1853 1854
{
	int error;

1855
	error = current_has_perm(target, PROCESS__GETCAP);
L
Linus Torvalds 已提交
1856 1857 1858
	if (error)
		return error;

1859
	return cap_capget(target, effective, inheritable, permitted);
L
Linus Torvalds 已提交
1860 1861
}

D
David Howells 已提交
1862 1863 1864 1865
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
1866 1867 1868
{
	int error;

1869
	error = cap_capset(new, old,
D
David Howells 已提交
1870
				      effective, inheritable, permitted);
L
Linus Torvalds 已提交
1871 1872 1873
	if (error)
		return error;

D
David Howells 已提交
1874
	return cred_has_perm(old, new, PROCESS__SETCAP);
L
Linus Torvalds 已提交
1875 1876
}

1877 1878 1879 1880 1881 1882 1883 1884 1885 1886
/*
 * (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.
 */

1887 1888
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
1889 1890 1891
{
	int rc;

1892
	rc = cap_capable(cred, ns, cap, audit);
L
Linus Torvalds 已提交
1893 1894 1895
	if (rc)
		return rc;

1896
	return cred_has_capability(cred, cap, audit);
L
Linus Torvalds 已提交
1897 1898 1899 1900
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
1901
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
1902 1903 1904 1905 1906 1907
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
1908 1909 1910 1911 1912
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
1913
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1914 1915 1916 1917
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
1918
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1919 1920 1921 1922
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
1923 1924 1925 1926 1927 1928
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
1929 1930
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
1931
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
1932 1933
}

1934
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
1935 1936 1937 1938
{
	int rc;

	switch (type) {
1939 1940
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
1941 1942
		rc = task_has_system(current, SYSTEM__SYSLOG_READ);
		break;
1943 1944 1945 1946
	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:
1947 1948
		rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
		break;
1949 1950 1951 1952 1953
	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 */
1954 1955 1956
	default:
		rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
		break;
L
Linus Torvalds 已提交
1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968
	}
	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.
 */
1969
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
1970 1971 1972
{
	int rc, cap_sys_admin = 0;

1973
	rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
1974
			     SECURITY_CAP_NOAUDIT);
L
Linus Torvalds 已提交
1975 1976 1977
	if (rc == 0)
		cap_sys_admin = 1;

1978
	return __vm_enough_memory(mm, pages, cap_sys_admin);
L
Linus Torvalds 已提交
1979 1980 1981 1982
}

/* binprm security operations */

1983
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
1984
{
1985 1986
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
1987
	struct inode_security_struct *isec;
1988
	struct common_audit_data ad;
1989
	struct selinux_audit_data sad = {0,};
1990
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1991 1992
	int rc;

1993
	rc = cap_bprm_set_creds(bprm);
L
Linus Torvalds 已提交
1994 1995 1996
	if (rc)
		return rc;

1997 1998 1999
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
	if (bprm->cred_prepared)
L
Linus Torvalds 已提交
2000 2001
		return 0;

2002 2003
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
L
Linus Torvalds 已提交
2004 2005 2006
	isec = inode->i_security;

	/* Default to the current task SID. */
2007 2008
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2009

2010
	/* Reset fs, key, and sock SIDs on execve. */
2011 2012 2013
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2014

2015 2016
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2017
		/* Reset exec SID on execve. */
2018
		new_tsec->exec_sid = 0;
L
Linus Torvalds 已提交
2019 2020
	} else {
		/* Check for a default transition on this program. */
2021
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2022 2023
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2024 2025 2026 2027
		if (rc)
			return rc;
	}

2028
	COMMON_AUDIT_DATA_INIT(&ad, PATH);
2029
	ad.selinux_audit_data = &sad;
2030
	ad.u.path = bprm->file->f_path;
L
Linus Torvalds 已提交
2031

J
Josef Sipek 已提交
2032
	if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2033
		new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2034

2035 2036
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2037 2038 2039 2040 2041
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2042
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2043 2044 2045 2046
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2047
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2048 2049 2050 2051
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069
		/* 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();
2070
			tracer = ptrace_parent(current);
2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084
			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
2085

2086 2087
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
L
Linus Torvalds 已提交
2088 2089 2090 2091 2092
	}

	return 0;
}

2093
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2094
{
2095
	const struct task_security_struct *tsec = current_security();
2096
	u32 sid, osid;
L
Linus Torvalds 已提交
2097 2098
	int atsecure = 0;

2099 2100 2101 2102
	sid = tsec->sid;
	osid = tsec->osid;

	if (osid != sid) {
L
Linus Torvalds 已提交
2103 2104 2105
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2106
		atsecure = avc_has_perm(osid, sid,
2107 2108
					SECCLASS_PROCESS,
					PROCESS__NOATSECURE, NULL);
L
Linus Torvalds 已提交
2109 2110
	}

2111
	return (atsecure || cap_bprm_secureexec(bprm));
L
Linus Torvalds 已提交
2112 2113 2114
}

/* Derived from fs/exec.c:flush_old_files. */
2115 2116
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2117
{
2118
	struct common_audit_data ad;
2119
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
2120
	struct file *file, *devnull = NULL;
2121
	struct tty_struct *tty;
2122
	struct fdtable *fdt;
L
Linus Torvalds 已提交
2123
	long j = -1;
2124
	int drop_tty = 0;
L
Linus Torvalds 已提交
2125

2126
	tty = get_current_tty();
L
Linus Torvalds 已提交
2127
	if (tty) {
N
Nick Piggin 已提交
2128
		spin_lock(&tty_files_lock);
2129
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2130
			struct tty_file_private *file_priv;
2131 2132
			struct inode *inode;

L
Linus Torvalds 已提交
2133 2134 2135 2136 2137
			/* Revalidate access to controlling tty.
			   Use inode_has_perm on the tty inode 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
2138 2139 2140
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2141
			inode = file->f_path.dentry->d_inode;
2142 2143
			if (inode_has_perm_noadp(cred, inode,
					   FILE__READ | FILE__WRITE, 0)) {
2144
				drop_tty = 1;
L
Linus Torvalds 已提交
2145 2146
			}
		}
N
Nick Piggin 已提交
2147
		spin_unlock(&tty_files_lock);
A
Alan Cox 已提交
2148
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2149
	}
2150 2151 2152
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2153 2154 2155

	/* Revalidate access to inherited open files. */

2156
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
2157
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
2158 2159 2160 2161 2162 2163 2164 2165

	spin_lock(&files->file_lock);
	for (;;) {
		unsigned long set, i;
		int fd;

		j++;
		i = j * __NFDBITS;
2166
		fdt = files_fdtable(files);
2167
		if (i >= fdt->max_fds)
L
Linus Torvalds 已提交
2168
			break;
2169
		set = fdt->open_fds[j];
L
Linus Torvalds 已提交
2170 2171 2172
		if (!set)
			continue;
		spin_unlock(&files->file_lock);
2173
		for ( ; set ; i++, set >>= 1) {
L
Linus Torvalds 已提交
2174 2175 2176 2177
			if (set & 1) {
				file = fget(i);
				if (!file)
					continue;
2178
				if (file_has_perm(cred,
L
Linus Torvalds 已提交
2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189
						  file,
						  file_to_av(file))) {
					sys_close(i);
					fd = get_unused_fd();
					if (fd != i) {
						if (fd >= 0)
							put_unused_fd(fd);
						fput(file);
						continue;
					}
					if (devnull) {
2190
						get_file(devnull);
L
Linus Torvalds 已提交
2191
					} else {
2192 2193 2194 2195
						devnull = dentry_open(
							dget(selinux_null),
							mntget(selinuxfs_mount),
							O_RDWR, cred);
2196 2197
						if (IS_ERR(devnull)) {
							devnull = NULL;
L
Linus Torvalds 已提交
2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213
							put_unused_fd(fd);
							fput(file);
							continue;
						}
					}
					fd_install(fd, devnull);
				}
				fput(file);
			}
		}
		spin_lock(&files->file_lock);

	}
	spin_unlock(&files->file_lock);
}

2214 2215 2216 2217
/*
 * 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
2218
{
2219 2220 2221
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2222

2223 2224 2225
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2226

2227 2228
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2229

2230 2231
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2232

2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245
	/* 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) {
2246 2247
		/* protect against do_prlimit() */
		task_lock(current);
2248 2249 2250 2251
		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
2252
		}
2253 2254
		task_unlock(current);
		update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2255 2256 2257 2258
	}
}

/*
2259 2260
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2261
 */
2262
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2263
{
2264
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2265
	struct itimerval itimer;
2266
	u32 osid, sid;
L
Linus Torvalds 已提交
2267 2268
	int rc, i;

2269 2270 2271 2272
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2273 2274
		return;

2275 2276 2277 2278 2279 2280 2281 2282
	/* 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
2283 2284 2285 2286 2287
	if (rc) {
		memset(&itimer, 0, sizeof itimer);
		for (i = 0; i < 3; i++)
			do_setitimer(i, &itimer, NULL);
		spin_lock_irq(&current->sighand->siglock);
2288 2289 2290 2291 2292
		if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
			__flush_signals(current);
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
		}
L
Linus Torvalds 已提交
2293 2294 2295
		spin_unlock_irq(&current->sighand->siglock);
	}

2296 2297
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2298
	read_lock(&tasklist_lock);
2299
	__wake_up_parent(current, current->real_parent);
2300
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
}

/* 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)
{
2325 2326 2327
	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) ||
2328 2329
		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
2330 2331 2332 2333 2334 2335 2336
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2337
	} else
L
Linus Torvalds 已提交
2338 2339 2340 2341 2342
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2343 2344
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2345 2346 2347 2348 2349 2350
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2351
	} else
2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363
		*first = 0;

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

2364
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2365 2366 2367 2368
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2369
	int open_quote = 0;
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384

	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 {
2385 2386 2387 2388
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2389 2390 2391
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2392
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2393 2394 2395 2396 2397 2398 2399
			else
				take_option(&nosec, in_curr, &fnosec, len);

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

2400
	strcpy(in_save, nosec_save);
2401
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2402 2403 2404 2405
out:
	return rc;
}

2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490
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;

		if (flags[i] == SE_SBLABELSUPP)
			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"
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
			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 "
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
	goto out_free_opts;
}

2491
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2492
{
2493
	const struct cred *cred = current_cred();
2494
	struct common_audit_data ad;
2495
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
2496 2497 2498 2499 2500 2501
	int rc;

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

2502 2503 2504 2505
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2506
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2507
	ad.selinux_audit_data = &sad;
2508
	ad.u.dentry = sb->s_root;
2509
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2510 2511
}

2512
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2513
{
2514
	const struct cred *cred = current_cred();
2515
	struct common_audit_data ad;
2516
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
2517

2518
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2519
	ad.selinux_audit_data = &sad;
2520
	ad.u.dentry = dentry->d_sb->s_root;
2521
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2522 2523
}

2524
static int selinux_mount(char *dev_name,
2525
			 struct path *path,
2526 2527 2528
			 char *type,
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2529
{
2530
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2531 2532

	if (flags & MS_REMOUNT)
2533
		return superblock_has_perm(cred, path->dentry->d_sb,
2534
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2535
	else
E
Eric Paris 已提交
2536
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2537 2538 2539 2540
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2541
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2542

2543
	return superblock_has_perm(cred, mnt->mnt_sb,
2544
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558
}

/* 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);
}

2559
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2560 2561
				       const struct qstr *qstr, char **name,
				       void **value, size_t *len)
2562
{
2563
	const struct task_security_struct *tsec = current_security();
2564 2565
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
2566
	u32 sid, newsid, clen;
2567
	int rc;
2568
	char *namep = NULL, *context;
2569 2570 2571 2572

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

2573 2574 2575
	sid = tsec->sid;
	newsid = tsec->create_sid;

2576 2577 2578 2579
	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
		newsid = sbsec->mntpoint_sid;
	else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2580
		rc = security_transition_sid(sid, dsec->sid,
2581
					     inode_mode_to_security_class(inode->i_mode),
2582
					     qstr, &newsid);
2583 2584 2585 2586
		if (rc) {
			printk(KERN_WARNING "%s:  "
			       "security_transition_sid failed, rc=%d (dev=%s "
			       "ino=%ld)\n",
2587
			       __func__,
2588 2589 2590 2591 2592
			       -rc, inode->i_sb->s_id, inode->i_ino);
			return rc;
		}
	}

2593
	/* Possibly defer initialization to selinux_complete_init. */
2594
	if (sbsec->flags & SE_SBINITIALIZED) {
2595 2596 2597 2598 2599
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
		isec->initialized = 1;
	}
2600

2601
	if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2602 2603
		return -EOPNOTSUPP;

2604
	if (name) {
2605
		namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2606 2607 2608 2609
		if (!namep)
			return -ENOMEM;
		*name = namep;
	}
2610

2611
	if (value && len) {
2612
		rc = security_sid_to_context_force(newsid, &context, &clen);
2613 2614 2615 2616 2617 2618
		if (rc) {
			kfree(namep);
			return rc;
		}
		*value = context;
		*len = clen;
2619 2620 2621 2622 2623
	}

	return 0;
}

A
Al Viro 已提交
2624
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643
{
	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);
}

2644
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2645 2646 2647 2648 2649 2650 2651 2652 2653
{
	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
2654
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2655 2656 2657 2658 2659
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2660
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2661 2662 2663 2664 2665 2666
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
2667 2668
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2669
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2670 2671 2672 2673
}

static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
{
2674
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2675

E
Eric Paris 已提交
2676
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
2677 2678
}

2679
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
2680
{
2681
	const struct cred *cred = current_cred();
2682
	struct common_audit_data ad;
2683
	struct selinux_audit_data sad = {0,};
2684 2685
	u32 perms;
	bool from_access;
2686
	unsigned flags = mask & MAY_NOT_BLOCK;
L
Linus Torvalds 已提交
2687

2688
	from_access = mask & MAY_ACCESS;
2689 2690
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

2691 2692
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
2693 2694
		return 0;

2695
	COMMON_AUDIT_DATA_INIT(&ad, INODE);
2696
	ad.selinux_audit_data = &sad;
2697
	ad.u.inode = inode;
2698 2699

	if (from_access)
2700
		ad.selinux_audit_data->auditdeny |= FILE__AUDIT_ACCESS;
2701 2702 2703

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

2704
	return inode_has_perm(cred, inode, perms, &ad, flags);
L
Linus Torvalds 已提交
2705 2706 2707 2708
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
2709
	const struct cred *cred = current_cred();
2710
	unsigned int ia_valid = iattr->ia_valid;
L
Linus Torvalds 已提交
2711

2712 2713 2714 2715 2716 2717 2718
	/* 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
2719

2720 2721
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
2722
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
2723

E
Eric Paris 已提交
2724
	return dentry_has_perm(cred, dentry, FILE__WRITE);
L
Linus Torvalds 已提交
2725 2726 2727 2728
}

static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
{
2729
	const struct cred *cred = current_cred();
E
Eric Paris 已提交
2730 2731 2732 2733
	struct path path;

	path.dentry = dentry;
	path.mnt = mnt;
2734

E
Eric Paris 已提交
2735
	return path_has_perm(cred, &path, FILE__GETATTR);
L
Linus Torvalds 已提交
2736 2737
}

2738
static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2739
{
2740 2741
	const struct cred *cred = current_cred();

2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755
	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
2756
	return dentry_has_perm(cred, dentry, FILE__SETATTR);
2757 2758
}

2759 2760
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
2761 2762 2763 2764
{
	struct inode *inode = dentry->d_inode;
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec;
2765
	struct common_audit_data ad;
2766
	struct selinux_audit_data sad = {0,};
2767
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
2768 2769
	int rc = 0;

2770 2771
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2772 2773

	sbsec = inode->i_sb->s_security;
2774
	if (!(sbsec->flags & SE_SBLABELSUPP))
L
Linus Torvalds 已提交
2775 2776
		return -EOPNOTSUPP;

2777
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
2778 2779
		return -EPERM;

2780
	COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2781
	ad.selinux_audit_data = &sad;
2782
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
2783

2784
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
2785 2786 2787 2788 2789
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

	rc = security_context_to_sid(value, size, &newsid);
2790 2791 2792 2793 2794
	if (rc == -EINVAL) {
		if (!capable(CAP_MAC_ADMIN))
			return rc;
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
2795 2796 2797
	if (rc)
		return rc;

2798
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
2799 2800 2801 2802
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

2803
	rc = security_validate_transition(isec->sid, newsid, sid,
2804
					  isec->sclass);
L
Linus Torvalds 已提交
2805 2806 2807 2808 2809 2810 2811 2812 2813 2814
	if (rc)
		return rc;

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

2815
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2816
					const void *value, size_t size,
2817
					int flags)
L
Linus Torvalds 已提交
2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828
{
	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;
	}

2829
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
2830
	if (rc) {
2831 2832 2833
		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
2834 2835 2836 2837 2838 2839 2840
		return;
	}

	isec->sid = newsid;
	return;
}

2841
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2842
{
2843 2844
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2845
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2846 2847
}

2848
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
2849
{
2850 2851
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2852
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
2853 2854
}

2855
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
2856
{
2857 2858
	if (strcmp(name, XATTR_NAME_SELINUX))
		return selinux_inode_setotherxattr(dentry, name);
L
Linus Torvalds 已提交
2859 2860 2861 2862 2863 2864

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

2865
/*
2866
 * Copy the inode security context value to the user.
2867 2868 2869
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
2870
static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
2871
{
2872 2873 2874
	u32 size;
	int error;
	char *context = NULL;
L
Linus Torvalds 已提交
2875
	struct inode_security_struct *isec = inode->i_security;
2876

2877 2878
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
2879

2880 2881 2882 2883 2884 2885 2886 2887 2888
	/*
	 * 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.
	 */
2889
	error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2890
				SECURITY_CAP_NOAUDIT);
2891 2892 2893 2894 2895
	if (!error)
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
2896 2897 2898 2899 2900 2901 2902 2903 2904 2905
	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
2906 2907 2908
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2909
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
{
	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;

2921
	rc = security_context_to_sid((void *)value, size, &newsid);
L
Linus Torvalds 已提交
2922 2923 2924 2925
	if (rc)
		return rc;

	isec->sid = newsid;
2926
	isec->initialized = 1;
L
Linus Torvalds 已提交
2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937
	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;
}

2938 2939 2940 2941 2942 2943
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
2944 2945
/* file security operations */

2946
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
2947
{
2948
	const struct cred *cred = current_cred();
J
Josef Sipek 已提交
2949
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
2950 2951 2952 2953 2954

	/* 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;

2955 2956
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
2957 2958
}

2959 2960
static int selinux_file_permission(struct file *file, int mask)
{
2961 2962 2963 2964 2965
	struct inode *inode = file->f_path.dentry->d_inode;
	struct file_security_struct *fsec = file->f_security;
	struct inode_security_struct *isec = inode->i_security;
	u32 sid = current_sid();

2966
	if (!mask)
2967 2968 2969
		/* No permission to check.  Existence test. */
		return 0;

2970 2971 2972 2973 2974
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
		/* No change since dentry_open check. */
		return 0;

2975 2976 2977
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990
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)
{
2991
	const struct cred *cred = current_cred();
2992
	int error = 0;
L
Linus Torvalds 已提交
2993

2994 2995 2996 2997 2998 2999 3000
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3001
	case FS_IOC_GETFLAGS:
3002
	/* fall through */
3003
	case FS_IOC_GETVERSION:
3004 3005
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3006

3007
	case FS_IOC_SETFLAGS:
3008
	/* fall through */
3009
	case FS_IOC_SETVERSION:
3010 3011 3012 3013 3014 3015 3016 3017 3018
		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
3019

3020 3021
	case KDSKBENT:
	case KDSKBSENT:
3022 3023
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
					    SECURITY_CAP_AUDIT);
3024 3025 3026 3027 3028 3029 3030 3031 3032
		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
3033 3034
}

3035 3036
static int default_noexec;

L
Linus Torvalds 已提交
3037 3038
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3039
	const struct cred *cred = current_cred();
D
David Howells 已提交
3040
	int rc = 0;
3041

3042 3043
	if (default_noexec &&
	    (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3044 3045 3046 3047 3048
		/*
		 * 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
3049
		rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
L
Linus Torvalds 已提交
3050
		if (rc)
D
David Howells 已提交
3051
			goto error;
L
Linus Torvalds 已提交
3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064
	}

	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;

3065
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3066
	}
D
David Howells 已提交
3067 3068 3069

error:
	return rc;
L
Linus Torvalds 已提交
3070 3071 3072
}

static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3073 3074
			     unsigned long prot, unsigned long flags,
			     unsigned long addr, unsigned long addr_only)
L
Linus Torvalds 已提交
3075
{
3076
	int rc = 0;
3077
	u32 sid = current_sid();
L
Linus Torvalds 已提交
3078

3079 3080 3081 3082 3083 3084
	/*
	 * 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.
	 */
3085
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3086 3087
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3088 3089 3090 3091 3092 3093
		if (rc)
			return rc;
	}

	/* do DAC check on address space usage */
	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3094
	if (rc || addr_only)
L
Linus Torvalds 已提交
3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
		return rc;

	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)
{
3108
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3109 3110 3111 3112

	if (selinux_checkreqprot)
		prot = reqprot;

3113 3114
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3115
		int rc = 0;
3116 3117
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
D
David Howells 已提交
3118
			rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3119 3120 3121
		} else if (!vma->vm_file &&
			   vma->vm_start <= vma->vm_mm->start_stack &&
			   vma->vm_end >= vma->vm_mm->start_stack) {
3122
			rc = current_has_perm(current, PROCESS__EXECSTACK);
3123 3124 3125 3126 3127 3128 3129 3130
		} 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
3131
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3132
		}
3133 3134 3135
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3136 3137 3138 3139 3140 3141

	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)
{
3142 3143 3144
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3145 3146 3147 3148 3149
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3150
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3151 3152 3153
	int err = 0;

	switch (cmd) {
3154 3155 3156 3157 3158
	case F_SETFL:
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
			break;
		}
L
Linus Torvalds 已提交
3159

3160
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3161
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3162
			break;
3163 3164 3165 3166 3167 3168 3169 3170
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
		/* Just check FD__USE permission */
3171
		err = file_has_perm(cred, file, 0);
3172 3173 3174 3175
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
L
Linus Torvalds 已提交
3176
#if BITS_PER_LONG == 32
3177 3178 3179
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3180
#endif
3181 3182
		if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
			err = -EINVAL;
L
Linus Torvalds 已提交
3183
			break;
3184
		}
3185
		err = file_has_perm(cred, file, FILE__LOCK);
3186
		break;
L
Linus Torvalds 已提交
3187 3188 3189 3190 3191 3192 3193 3194 3195 3196
	}

	return err;
}

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

	fsec = file->f_security;
3197
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3198 3199 3200 3201 3202 3203 3204

	return 0;
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3205
	struct file *file;
3206
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3207 3208 3209 3210
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3211
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3212 3213 3214 3215 3216 3217 3218 3219

	fsec = file->f_security;

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

3220
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3221 3222 3223 3224 3225
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3226 3227 3228
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3229 3230
}

3231
static int selinux_dentry_open(struct file *file, const struct cred *cred)
3232 3233 3234 3235
{
	struct file_security_struct *fsec;
	struct inode *inode;
	struct inode_security_struct *isec;
D
David Howells 已提交
3236

3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256
	inode = file->f_path.dentry->d_inode;
	fsec = file->f_security;
	isec = inode->i_security;
	/*
	 * 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.
	 */
3257
	return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3258 3259
}

L
Linus Torvalds 已提交
3260 3261 3262 3263
/* task security operations */

static int selinux_task_create(unsigned long clone_flags)
{
3264
	return current_has_perm(current, PROCESS__FORK);
L
Linus Torvalds 已提交
3265 3266
}

3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281
/*
 * 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
3282 3283 3284 3285
/*
 * 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
3286
{
D
David Howells 已提交
3287
	struct task_security_struct *tsec = cred->security;
3288

3289 3290 3291 3292 3293
	/*
	 * 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);
3294
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3295 3296
	kfree(tsec);
}
L
Linus Torvalds 已提交
3297

D
David Howells 已提交
3298 3299 3300 3301 3302 3303 3304 3305
/*
 * 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
3306

D
David Howells 已提交
3307
	old_tsec = old->security;
L
Linus Torvalds 已提交
3308

D
David Howells 已提交
3309 3310 3311
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3312

D
David Howells 已提交
3313
	new->security = tsec;
L
Linus Torvalds 已提交
3314 3315 3316
	return 0;
}

3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327
/*
 * 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;
}

3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368
/*
 * 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;
3369
	return ret;
3370 3371
}

3372
static int selinux_kernel_module_request(char *kmod_name)
3373
{
3374 3375
	u32 sid;
	struct common_audit_data ad;
3376
	struct selinux_audit_data sad = {0,};
3377 3378 3379 3380

	sid = task_sid(current);

	COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3381
	ad.selinux_audit_data = &sad;
3382 3383 3384 3385
	ad.u.kmod_name = kmod_name;

	return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
			    SYSTEM__MODULE_REQUEST, &ad);
3386 3387
}

L
Linus Torvalds 已提交
3388 3389
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3390
	return current_has_perm(p, PROCESS__SETPGID);
L
Linus Torvalds 已提交
3391 3392 3393 3394
}

static int selinux_task_getpgid(struct task_struct *p)
{
3395
	return current_has_perm(p, PROCESS__GETPGID);
L
Linus Torvalds 已提交
3396 3397 3398 3399
}

static int selinux_task_getsid(struct task_struct *p)
{
3400
	return current_has_perm(p, PROCESS__GETSESSION);
L
Linus Torvalds 已提交
3401 3402
}

3403 3404
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3405
	*secid = task_sid(p);
3406 3407
}

L
Linus Torvalds 已提交
3408 3409 3410 3411
static int selinux_task_setnice(struct task_struct *p, int nice)
{
	int rc;

3412
	rc = cap_task_setnice(p, nice);
L
Linus Torvalds 已提交
3413 3414 3415
	if (rc)
		return rc;

3416
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3417 3418
}

3419 3420
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3421 3422
	int rc;

3423
	rc = cap_task_setioprio(p, ioprio);
3424 3425 3426
	if (rc)
		return rc;

3427
	return current_has_perm(p, PROCESS__SETSCHED);
3428 3429
}

3430 3431
static int selinux_task_getioprio(struct task_struct *p)
{
3432
	return current_has_perm(p, PROCESS__GETSCHED);
3433 3434
}

3435 3436
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3437
{
3438
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3439 3440 3441 3442

	/* 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
3443
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3444
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3445
		return current_has_perm(p, PROCESS__SETRLIMIT);
L
Linus Torvalds 已提交
3446 3447 3448 3449

	return 0;
}

3450
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
3451
{
3452 3453
	int rc;

3454
	rc = cap_task_setscheduler(p);
3455 3456 3457
	if (rc)
		return rc;

3458
	return current_has_perm(p, PROCESS__SETSCHED);
L
Linus Torvalds 已提交
3459 3460 3461 3462
}

static int selinux_task_getscheduler(struct task_struct *p)
{
3463
	return current_has_perm(p, PROCESS__GETSCHED);
L
Linus Torvalds 已提交
3464 3465
}

3466 3467
static int selinux_task_movememory(struct task_struct *p)
{
3468
	return current_has_perm(p, PROCESS__SETSCHED);
3469 3470
}

3471 3472
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
3473 3474 3475 3476 3477 3478 3479 3480
{
	u32 perm;
	int rc;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
3481
	if (secid)
3482 3483
		rc = avc_has_perm(secid, task_sid(p),
				  SECCLASS_PROCESS, perm, NULL);
3484
	else
3485
		rc = current_has_perm(p, perm);
3486
	return rc;
L
Linus Torvalds 已提交
3487 3488 3489 3490
}

static int selinux_task_wait(struct task_struct *p)
{
3491
	return task_has_perm(p, current, PROCESS__SIGCHLD);
L
Linus Torvalds 已提交
3492 3493 3494 3495 3496 3497
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
3498
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
3499

3500
	isec->sid = sid;
L
Linus Torvalds 已提交
3501 3502 3503 3504
	isec->initialized = 1;
}

/* Returns error only if unable to parse addresses */
3505
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3506
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3507 3508 3509 3510
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

3511
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

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

	ad->u.net.v4info.saddr = ih->saddr;
	ad->u.net.v4info.daddr = ih->daddr;
	ret = 0;

3524 3525 3526
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
3527
	switch (ih->protocol) {
3528 3529
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3530

3531 3532
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
3533 3534 3535 3536 3537 3538 3539 3540 3541

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

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
3542 3543 3544 3545 3546 3547 3548 3549
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

L
Linus Torvalds 已提交
3550
		offset += ihlen;
3551
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
3552
		if (uh == NULL)
3553
			break;
L
Linus Torvalds 已提交
3554

3555 3556 3557 3558
		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}
L
Linus Torvalds 已提交
3559

J
James Morris 已提交
3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573
	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;

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3574
	}
J
James Morris 已提交
3575

3576 3577 3578
	default:
		break;
	}
L
Linus Torvalds 已提交
3579 3580 3581 3582 3583 3584 3585
out:
	return ret;
}

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

/* Returns error only if unable to parse addresses */
3586
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3587
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
3588 3589 3590 3591
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
3592
	__be16 frag_off;
L
Linus Torvalds 已提交
3593

3594
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
3595 3596 3597 3598
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

A
Alexey Dobriyan 已提交
3599 3600
	ad->u.net.v6info.saddr = ip6->saddr;
	ad->u.net.v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
3601 3602 3603 3604
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
3605
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
3606 3607 3608
	if (offset < 0)
		goto out;

3609 3610 3611
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
3612 3613
	switch (nexthdr) {
	case IPPROTO_TCP: {
3614
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636

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

		ad->u.net.sport = th->source;
		ad->u.net.dport = th->dest;
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

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

		ad->u.net.sport = uh->source;
		ad->u.net.dport = uh->dest;
		break;
	}

J
James Morris 已提交
3637 3638 3639 3640 3641 3642 3643 3644 3645 3646
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

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

		ad->u.net.sport = dh->dccph_sport;
		ad->u.net.dport = dh->dccph_dport;
		break;
3647
	}
J
James Morris 已提交
3648

L
Linus Torvalds 已提交
3649 3650 3651 3652 3653 3654 3655 3656 3657 3658
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

3659
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3660
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
3661
{
3662 3663
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
3664 3665 3666

	switch (ad->u.net.family) {
	case PF_INET:
3667
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
3668 3669 3670 3671 3672
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v4info.saddr :
				       &ad->u.net.v4info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3673 3674 3675

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	case PF_INET6:
3676
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
3677 3678 3679 3680 3681
		if (ret)
			goto parse_error;
		addrp = (char *)(src ? &ad->u.net.v6info.saddr :
				       &ad->u.net.v6info.daddr);
		goto okay;
L
Linus Torvalds 已提交
3682 3683
#endif	/* IPV6 */
	default:
3684 3685
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
3686 3687
	}

3688 3689 3690 3691
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
3692
	return ret;
3693 3694 3695 3696 3697

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
3698 3699
}

3700
/**
3701
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3702
 * @skb: the packet
3703
 * @family: protocol family
3704
 * @sid: the packet's peer label SID
3705 3706
 *
 * Description:
3707 3708 3709 3710 3711 3712
 * 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.
3713 3714
 *
 */
3715
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3716
{
3717
	int err;
3718 3719
	u32 xfrm_sid;
	u32 nlbl_sid;
3720
	u32 nlbl_type;
3721 3722

	selinux_skb_xfrm_sid(skb, &xfrm_sid);
3723
	selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3724

3725 3726 3727 3728 3729
	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");
3730
		return -EACCES;
3731
	}
3732 3733

	return 0;
3734 3735
}

L
Linus Torvalds 已提交
3736
/* socket security operations */
3737

3738 3739
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
3740
{
3741 3742 3743 3744 3745 3746 3747
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
3748 3749
}

3750
static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
3751
{
3752
	struct sk_security_struct *sksec = sk->sk_security;
3753
	struct common_audit_data ad;
3754
	struct selinux_audit_data sad = {0,};
3755
	u32 tsid = task_sid(task);
L
Linus Torvalds 已提交
3756

3757 3758
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
3759

3760
	COMMON_AUDIT_DATA_INIT(&ad, NET);
3761
	ad.selinux_audit_data = &sad;
3762
	ad.u.net.sk = sk;
L
Linus Torvalds 已提交
3763

3764
	return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
L
Linus Torvalds 已提交
3765 3766 3767 3768 3769
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
3770
	const struct task_security_struct *tsec = current_security();
3771
	u32 newsid;
3772
	u16 secclass;
3773
	int rc;
L
Linus Torvalds 已提交
3774 3775

	if (kern)
3776
		return 0;
3777 3778

	secclass = socket_type_to_security_class(family, type, protocol);
3779 3780 3781 3782
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

3783
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
3784 3785
}

V
Venkat Yekkirala 已提交
3786 3787
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
3788
{
3789
	const struct task_security_struct *tsec = current_security();
3790
	struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3791
	struct sk_security_struct *sksec;
3792 3793
	int err = 0;

3794 3795
	isec->sclass = socket_type_to_security_class(family, type, protocol);

3796 3797
	if (kern)
		isec->sid = SECINITSID_KERNEL;
3798 3799 3800 3801 3802
	else {
		err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
		if (err)
			return err;
	}
3803

L
Linus Torvalds 已提交
3804 3805
	isec->initialized = 1;

3806 3807 3808
	if (sock->sk) {
		sksec = sock->sk->sk_security;
		sksec->sid = isec->sid;
3809
		sksec->sclass = isec->sclass;
3810
		err = selinux_netlbl_socket_post_create(sock->sk, family);
3811 3812
	}

V
Venkat Yekkirala 已提交
3813
	return err;
L
Linus Torvalds 已提交
3814 3815 3816 3817 3818 3819 3820 3821
}

/* 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)
{
3822
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
3823 3824 3825
	u16 family;
	int err;

3826
	err = sock_has_perm(current, sk, SOCKET__BIND);
L
Linus Torvalds 已提交
3827 3828 3829 3830 3831
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
3832 3833
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
3834
	 */
3835
	family = sk->sk_family;
L
Linus Torvalds 已提交
3836 3837
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
3838
		struct sk_security_struct *sksec = sk->sk_security;
3839
		struct common_audit_data ad;
3840
		struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
3841 3842 3843
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
3844
		u32 sid, node_perm;
L
Linus Torvalds 已提交
3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855

		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;
		}

3856 3857 3858 3859 3860 3861
		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
3862 3863
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
3864 3865
				if (err)
					goto out;
3866
				COMMON_AUDIT_DATA_INIT(&ad, NET);
3867
				ad.selinux_audit_data = &sad;
3868 3869
				ad.u.net.sport = htons(snum);
				ad.u.net.family = family;
3870 3871
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
3872 3873 3874 3875
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
3876
		}
3877

3878
		switch (sksec->sclass) {
3879
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
3880 3881
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
3882

3883
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
3884 3885
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
3886 3887 3888 3889 3890

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
3891 3892 3893 3894
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
3895

3896
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
3897 3898
		if (err)
			goto out;
3899

3900
		COMMON_AUDIT_DATA_INIT(&ad, NET);
3901
		ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
3902 3903 3904 3905 3906 3907
		ad.u.net.sport = htons(snum);
		ad.u.net.family = family;

		if (family == PF_INET)
			ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
		else
A
Alexey Dobriyan 已提交
3908
			ad.u.net.v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
3909

3910 3911
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
3912 3913 3914 3915 3916 3917 3918 3919 3920
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
3921
	struct sock *sk = sock->sk;
3922
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
3923 3924
	int err;

3925
	err = sock_has_perm(current, sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
3926 3927 3928 3929
	if (err)
		return err;

	/*
J
James Morris 已提交
3930
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
3931
	 */
3932 3933
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
3934
		struct common_audit_data ad;
3935
		struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
3936 3937 3938
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
3939
		u32 sid, perm;
L
Linus Torvalds 已提交
3940 3941 3942

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
3943
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
3944 3945 3946 3947
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
3948
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
3949 3950 3951 3952
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
3953
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
3954 3955 3956
		if (err)
			goto out;

3957
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
3958 3959
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

3960
		COMMON_AUDIT_DATA_INIT(&ad, NET);
3961
		ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
3962 3963
		ad.u.net.dport = htons(snum);
		ad.u.net.family = sk->sk_family;
3964
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
3965 3966 3967 3968
		if (err)
			goto out;
	}

3969 3970
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
3971 3972 3973 3974 3975 3976
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
3977
	return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
3978 3979 3980 3981 3982 3983 3984 3985
}

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

3986
	err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
3987 3988 3989 3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000
	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,
4001
				  int size)
L
Linus Torvalds 已提交
4002
{
4003
	return sock_has_perm(current, sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4004 4005 4006 4007 4008
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4009
	return sock_has_perm(current, sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4010 4011 4012 4013
}

static int selinux_socket_getsockname(struct socket *sock)
{
4014
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4015 4016 4017 4018
}

static int selinux_socket_getpeername(struct socket *sock)
{
4019
	return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4020 4021
}

4022
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4023
{
4024 4025
	int err;

4026
	err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4027 4028 4029 4030
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4031 4032 4033 4034 4035
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4036
	return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4037 4038 4039 4040
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4041
	return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4042 4043
}

4044 4045
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4046 4047
					      struct sock *newsk)
{
4048 4049
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4050
	struct sk_security_struct *sksec_new = newsk->sk_security;
4051
	struct common_audit_data ad;
4052
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
4053 4054
	int err;

4055
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4056
	ad.selinux_audit_data = &sad;
4057
	ad.u.net.sk = other;
L
Linus Torvalds 已提交
4058

4059 4060
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4061 4062 4063 4064 4065
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4066 4067 4068 4069 4070
	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;
4071

4072 4073 4074 4075
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4076 4077 4078 4079 4080
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4081 4082
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4083
	struct common_audit_data ad;
4084
	struct selinux_audit_data sad = {0,};
L
Linus Torvalds 已提交
4085

4086
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4087
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
4088 4089
	ad.u.net.sk = other->sk;

4090 4091
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4092 4093
}

4094 4095
static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
				    u32 peer_sid,
4096
				    struct common_audit_data *ad)
4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116
{
	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);
}

4117
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4118
				       u16 family)
4119
{
4120
	int err = 0;
4121 4122
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4123
	struct common_audit_data ad;
4124
	struct selinux_audit_data sad = {0,};
4125 4126
	char *addrp;

4127
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4128
	ad.selinux_audit_data = &sad;
4129
	ad.u.net.netif = skb->skb_iif;
4130 4131 4132 4133
	ad.u.net.family = family;
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4134

4135
	if (selinux_secmark_enabled()) {
4136
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4137
				   PACKET__RECV, &ad);
4138 4139 4140
		if (err)
			return err;
	}
4141

4142 4143 4144 4145
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4146

4147 4148 4149 4150 4151
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4152
	int err;
4153
	struct sk_security_struct *sksec = sk->sk_security;
4154 4155
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4156
	struct common_audit_data ad;
4157
	struct selinux_audit_data sad = {0,};
4158
	char *addrp;
4159 4160
	u8 secmark_active;
	u8 peerlbl_active;
4161 4162

	if (family != PF_INET && family != PF_INET6)
4163
		return 0;
4164 4165

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4166
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4167 4168
		family = PF_INET;

4169 4170 4171 4172
	/* 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. */
4173
	if (!selinux_policycap_netpeer)
4174 4175 4176 4177 4178 4179 4180
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return 0;

4181
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4182
	ad.selinux_audit_data = &sad;
4183
	ad.u.net.netif = skb->skb_iif;
4184
	ad.u.net.family = family;
4185
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4186
	if (err)
4187
		return err;
4188

4189
	if (peerlbl_active) {
4190 4191 4192
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4193 4194
		if (err)
			return err;
4195
		err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4196
					       peer_sid, &ad);
4197 4198
		if (err) {
			selinux_netlbl_err(skb, err, 0);
4199
			return err;
4200
		}
4201 4202
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
4203 4204
		if (err)
			selinux_netlbl_err(skb, err, 0);
4205 4206
	}

4207
	if (secmark_active) {
4208 4209 4210 4211 4212 4213
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4214
	return err;
L
Linus Torvalds 已提交
4215 4216
}

C
Catherine Zhang 已提交
4217 4218
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4219 4220 4221 4222
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4223
	struct sk_security_struct *sksec = sock->sk->sk_security;
4224
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4225

4226 4227
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4228
		peer_sid = sksec->peer_sid;
4229 4230
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4231

C
Catherine Zhang 已提交
4232
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4233
	if (err)
4234
		return err;
L
Linus Torvalds 已提交
4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250

	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;
}

4251
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4252
{
4253
	u32 peer_secid = SECSID_NULL;
4254
	u16 family;
C
Catherine Zhang 已提交
4255

4256 4257 4258 4259 4260
	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)
4261 4262 4263 4264 4265
		family = sock->sk->sk_family;
	else
		goto out;

	if (sock && family == PF_UNIX)
4266
		selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4267
	else if (skb)
4268
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4269

4270
out:
4271
	*secid = peer_secid;
4272 4273 4274
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4275 4276
}

A
Al Viro 已提交
4277
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4278
{
4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290
	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
4291 4292 4293 4294
}

static void selinux_sk_free_security(struct sock *sk)
{
4295 4296 4297 4298 4299
	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
4300 4301
}

4302
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4303
{
4304 4305
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4306

4307 4308 4309
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4310

4311
	selinux_netlbl_sk_security_reset(newsksec);
4312 4313
}

V
Venkat Yekkirala 已提交
4314
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4315
{
4316
	if (!sk)
V
Venkat Yekkirala 已提交
4317
		*secid = SECINITSID_ANY_SOCKET;
4318 4319
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4320

V
Venkat Yekkirala 已提交
4321
		*secid = sksec->sid;
4322
	}
4323 4324
}

4325
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4326 4327 4328 4329
{
	struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
	struct sk_security_struct *sksec = sk->sk_security;

4330 4331 4332
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
		isec->sid = sksec->sid;
4333
	sksec->sclass = isec->sclass;
4334 4335
}

4336 4337
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4338 4339 4340
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4341
	u16 family = sk->sk_family;
V
Venkat Yekkirala 已提交
4342
	u32 newsid;
4343 4344
	u32 peersid;

4345 4346 4347 4348 4349
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4350 4351
	if (err)
		return err;
4352 4353
	if (peersid == SECSID_NULL) {
		req->secid = sksec->sid;
4354
		req->peer_secid = SECSID_NULL;
4355 4356 4357 4358 4359 4360
	} else {
		err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
		if (err)
			return err;
		req->secid = newsid;
		req->peer_secid = peersid;
4361 4362
	}

4363
	return selinux_netlbl_inet_conn_request(req, family);
4364 4365
}

4366 4367
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4368 4369 4370 4371
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4372
	newsksec->peer_sid = req->peer_secid;
4373 4374 4375 4376
	/* 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. */
4377

P
Paul Moore 已提交
4378 4379
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4380
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4381 4382
}

4383
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4384
{
4385
	u16 family = sk->sk_family;
4386 4387
	struct sk_security_struct *sksec = sk->sk_security;

4388 4389 4390 4391 4392
	/* 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);
4393 4394
}

4395 4396 4397 4398 4399 4400 4401 4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415
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);
}

4416 4417
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
4418
{
4419
	fl->flowi_secid = req->secid;
4420 4421
}

4422 4423 4424 4425 4426 4427 4428 4429 4430 4431 4432 4433 4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474
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);
}

static void selinux_tun_dev_post_create(struct sock *sk)
{
	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 */

	/* see the comments in selinux_tun_dev_create() about why we don't use
	 * the sockcreate SID here */

	sksec->sid = current_sid();
	sksec->sclass = SECCLASS_TUN_SOCKET;
}

static int selinux_tun_dev_attach(struct sock *sk)
{
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sid = current_sid();
	int err;

	err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
			   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;

	sksec->sid = sid;

	return 0;
}

L
Linus Torvalds 已提交
4475 4476 4477 4478 4479
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
4480
	struct sk_security_struct *sksec = sk->sk_security;
4481

L
Linus Torvalds 已提交
4482 4483 4484 4485
	if (skb->len < NLMSG_SPACE(0)) {
		err = -EINVAL;
		goto out;
	}
4486
	nlh = nlmsg_hdr(skb);
4487

4488
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
4489 4490
	if (err) {
		if (err == -EINVAL) {
4491
			audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
L
Linus Torvalds 已提交
4492 4493
				  "SELinux:  unrecognized netlink message"
				  " type=%hu for sclass=%hu\n",
4494
				  nlh->nlmsg_type, sksec->sclass);
4495
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
4496 4497 4498 4499 4500 4501 4502 4503 4504
				err = 0;
		}

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

4505
	err = sock_has_perm(current, sk, perm);
L
Linus Torvalds 已提交
4506 4507 4508 4509 4510 4511
out:
	return err;
}

#ifdef CONFIG_NETFILTER

4512 4513
static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
				       u16 family)
L
Linus Torvalds 已提交
4514
{
4515
	int err;
4516 4517
	char *addrp;
	u32 peer_sid;
4518
	struct common_audit_data ad;
4519
	struct selinux_audit_data sad = {0,};
4520
	u8 secmark_active;
4521
	u8 netlbl_active;
4522
	u8 peerlbl_active;
4523

4524 4525
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
4526

4527
	secmark_active = selinux_secmark_enabled();
4528 4529
	netlbl_active = netlbl_enabled();
	peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4530 4531
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
4532

4533 4534 4535
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

4536
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4537
	ad.selinux_audit_data = &sad;
4538 4539 4540 4541 4542
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

4543 4544 4545 4546 4547
	if (peerlbl_active) {
		err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
					       peer_sid, &ad);
		if (err) {
			selinux_netlbl_err(skb, err, 1);
4548
			return NF_DROP;
4549 4550
		}
	}
4551 4552 4553 4554 4555 4556

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

4557 4558 4559 4560 4561 4562 4563 4564
	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;

4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587
	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 */

4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
	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 */
	if (skb->sk) {
		struct sk_security_struct *sksec = skb->sk->sk_security;
		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);
}

4619 4620
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
4621
						u16 family)
4622 4623 4624
{
	struct sock *sk = skb->sk;
	struct sk_security_struct *sksec;
4625
	struct common_audit_data ad;
4626
	struct selinux_audit_data sad = {0,};
4627 4628
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
4629

4630 4631 4632 4633
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

4634
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4635
	ad.selinux_audit_data = &sad;
4636 4637 4638 4639 4640
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

4641
	if (selinux_secmark_enabled())
4642
		if (avc_has_perm(sksec->sid, skb->secmark,
4643
				 SECCLASS_PACKET, PACKET__SEND, &ad))
4644
			return NF_DROP_ERR(-ECONNREFUSED);
4645

4646 4647
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
4648 4649

	return NF_ACCEPT;
4650 4651
}

4652 4653
static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
					 u16 family)
4654
{
4655 4656
	u32 secmark_perm;
	u32 peer_sid;
4657
	struct sock *sk;
4658
	struct common_audit_data ad;
4659
	struct selinux_audit_data sad = {0,};
4660 4661 4662
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
4663

4664 4665 4666 4667
	/* 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. */
4668
	if (!selinux_policycap_netpeer)
4669
		return selinux_ip_postroute_compat(skb, ifindex, family);
4670
#ifdef CONFIG_XFRM
4671 4672 4673 4674 4675 4676
	/* 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
	 *       is NULL, in this case go ahead and apply access control. */
E
Eric Dumazet 已提交
4677
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4678
		return NF_ACCEPT;
4679
#endif
4680 4681 4682 4683 4684
	secmark_active = selinux_secmark_enabled();
	peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

4685 4686 4687 4688
	/* if the packet is being forwarded then get the peer label from the
	 * packet itself; otherwise check to see if it is from a local
	 * application or the kernel, if from an application get the peer label
	 * from the sending socket, otherwise use the kernel's sid */
4689
	sk = skb->sk;
4690
	if (sk == NULL) {
4691 4692
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
4693
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4694
				return NF_DROP;
4695 4696
		} else {
			secmark_perm = PACKET__SEND;
4697
			peer_sid = SECINITSID_KERNEL;
4698
		}
4699
	} else {
4700 4701 4702 4703
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
4704

4705
	COMMON_AUDIT_DATA_INIT(&ad, NET);
4706
	ad.selinux_audit_data = &sad;
4707 4708 4709
	ad.u.net.netif = ifindex;
	ad.u.net.family = family;
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4710
		return NF_DROP;
4711

4712 4713 4714
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
4715
			return NF_DROP_ERR(-ECONNREFUSED);
4716 4717 4718 4719 4720 4721

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

		if (sel_netif_sid(ifindex, &if_sid))
4722
			return NF_DROP;
4723 4724
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4725
			return NF_DROP_ERR(-ECONNREFUSED);
4726 4727

		if (sel_netnode_sid(addrp, family, &node_sid))
4728
			return NF_DROP;
4729 4730
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
4731
			return NF_DROP_ERR(-ECONNREFUSED);
4732
	}
4733

4734
	return NF_ACCEPT;
L
Linus Torvalds 已提交
4735 4736
}

4737 4738 4739 4740 4741
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
4742
{
4743
	return selinux_ip_postroute(skb, out->ifindex, PF_INET);
L
Linus Torvalds 已提交
4744 4745 4746
}

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4747 4748 4749 4750 4751
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
4752
{
4753
	return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
L
Linus Torvalds 已提交
4754 4755 4756 4757 4758 4759 4760 4761 4762
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

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

4763
	err = cap_netlink_send(sk, skb);
L
Linus Torvalds 已提交
4764 4765 4766
	if (err)
		return err;

4767
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
4768 4769 4770 4771 4772 4773 4774
}

static int ipc_alloc_security(struct task_struct *task,
			      struct kern_ipc_perm *perm,
			      u16 sclass)
{
	struct ipc_security_struct *isec;
4775
	u32 sid;
L
Linus Torvalds 已提交
4776

J
James Morris 已提交
4777
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4778 4779 4780
	if (!isec)
		return -ENOMEM;

4781
	sid = task_sid(task);
L
Linus Torvalds 已提交
4782
	isec->sclass = sclass;
4783
	isec->sid = sid;
L
Linus Torvalds 已提交
4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799
	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
4800
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
4801 4802 4803 4804 4805 4806 4807 4808 4809 4810 4811 4812 4813 4814 4815 4816 4817 4818
	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,
4819
			u32 perms)
L
Linus Torvalds 已提交
4820 4821
{
	struct ipc_security_struct *isec;
4822
	struct common_audit_data ad;
4823
	struct selinux_audit_data sad = {0,};
4824
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4825 4826 4827

	isec = ipc_perms->security;

4828
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4829
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
4830 4831
	ad.u.ipc_id = ipc_perms->key;

4832
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848
}

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;
4849
	struct common_audit_data ad;
4850
	struct selinux_audit_data sad = {0,};
4851
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4852 4853 4854 4855 4856 4857 4858 4859
	int rc;

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

	isec = msq->q_perm.security;

4860
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4861
	ad.selinux_audit_data = &sad;
4862
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4863

4864
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880
			  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;
4881
	struct common_audit_data ad;
4882
	struct selinux_audit_data sad = {0,};
4883
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4884 4885 4886

	isec = msq->q_perm.security;

4887
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4888
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
4889 4890
	ad.u.ipc_id = msq->q_perm.key;

4891
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4892 4893 4894 4895 4896 4897 4898 4899
			    MSGQ__ASSOCIATE, &ad);
}

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

4900
	switch (cmd) {
L
Linus Torvalds 已提交
4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918
	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;
	}

4919
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
4920 4921 4922 4923 4924 4925 4926
	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;
4927
	struct common_audit_data ad;
4928
	struct selinux_audit_data sad = {0,};
4929
	u32 sid = current_sid();
L
Linus Torvalds 已提交
4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942
	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
		 */
4943
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4944
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
4945 4946 4947 4948
		if (rc)
			return rc;
	}

4949
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4950
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
4951 4952 4953
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
4954
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
4955 4956 4957
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
4958 4959
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
4960 4961
	if (!rc)
		/* Can the message be put in the queue? */
4962 4963
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
4964 4965 4966 4967 4968 4969 4970 4971 4972 4973

	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;
4974
	struct common_audit_data ad;
4975
	struct selinux_audit_data sad = {0,};
4976
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
4977 4978 4979 4980 4981
	int rc;

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

4982
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
4983
	ad.selinux_audit_data = &sad;
4984
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
4985

4986
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
4987 4988
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
4989
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
4990 4991 4992 4993 4994 4995 4996 4997
				  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;
4998
	struct common_audit_data ad;
4999
	struct selinux_audit_data sad = {0,};
5000
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5001 5002 5003 5004 5005 5006 5007 5008
	int rc;

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

	isec = shp->shm_perm.security;

5009
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5010
	ad.selinux_audit_data = &sad;
5011
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5012

5013
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029
			  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;
5030
	struct common_audit_data ad;
5031
	struct selinux_audit_data sad = {0,};
5032
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5033 5034 5035

	isec = shp->shm_perm.security;

5036
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5037
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
5038 5039
	ad.u.ipc_id = shp->shm_perm.key;

5040
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5041 5042 5043 5044 5045 5046 5047 5048 5049
			    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;

5050
	switch (cmd) {
L
Linus Torvalds 已提交
5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072
	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;
	}

5073
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084 5085 5086
	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;

5087
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5088 5089 5090 5091 5092 5093
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5094
	struct common_audit_data ad;
5095
	struct selinux_audit_data sad = {0,};
5096
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5097 5098 5099 5100 5101 5102 5103 5104
	int rc;

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

	isec = sma->sem_perm.security;

5105
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5106
	ad.selinux_audit_data = &sad;
5107
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5108

5109
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122 5123 5124 5125
			  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;
5126
	struct common_audit_data ad;
5127
	struct selinux_audit_data sad = {0,};
5128
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5129 5130 5131

	isec = sma->sem_perm.security;

5132
	COMMON_AUDIT_DATA_INIT(&ad, IPC);
5133
	ad.selinux_audit_data = &sad;
L
Linus Torvalds 已提交
5134 5135
	ad.u.ipc_id = sma->sem_perm.key;

5136
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5137 5138 5139 5140 5141 5142 5143 5144 5145
			    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;

5146
	switch (cmd) {
L
Linus Torvalds 已提交
5147 5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177
	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;
	}

5178
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191
	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;

5192
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5193 5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207
}

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;

5208
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5209 5210
}

5211 5212 5213 5214 5215 5216
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5217
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5218 5219 5220 5221 5222 5223
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5224
			       char *name, char **value)
L
Linus Torvalds 已提交
5225
{
5226
	const struct task_security_struct *__tsec;
5227
	u32 sid;
L
Linus Torvalds 已提交
5228
	int error;
5229
	unsigned len;
L
Linus Torvalds 已提交
5230 5231

	if (current != p) {
5232
		error = current_has_perm(p, PROCESS__GETATTR);
L
Linus Torvalds 已提交
5233 5234 5235 5236
		if (error)
			return error;
	}

5237 5238
	rcu_read_lock();
	__tsec = __task_cred(p)->security;
L
Linus Torvalds 已提交
5239 5240

	if (!strcmp(name, "current"))
5241
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5242
	else if (!strcmp(name, "prev"))
5243
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5244
	else if (!strcmp(name, "exec"))
5245
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5246
	else if (!strcmp(name, "fscreate"))
5247
		sid = __tsec->create_sid;
5248
	else if (!strcmp(name, "keycreate"))
5249
		sid = __tsec->keycreate_sid;
5250
	else if (!strcmp(name, "sockcreate"))
5251
		sid = __tsec->sockcreate_sid;
L
Linus Torvalds 已提交
5252
	else
5253 5254
		goto invalid;
	rcu_read_unlock();
L
Linus Torvalds 已提交
5255 5256 5257 5258

	if (!sid)
		return 0;

5259 5260 5261 5262
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5263 5264 5265 5266

invalid:
	rcu_read_unlock();
	return -EINVAL;
L
Linus Torvalds 已提交
5267 5268 5269 5270 5271 5272
}

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
5273
	struct task_struct *tracer;
D
David Howells 已提交
5274 5275
	struct cred *new;
	u32 sid = 0, ptsid;
L
Linus Torvalds 已提交
5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290
	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"))
5291
		error = current_has_perm(p, PROCESS__SETEXEC);
L
Linus Torvalds 已提交
5292
	else if (!strcmp(name, "fscreate"))
5293
		error = current_has_perm(p, PROCESS__SETFSCREATE);
5294
	else if (!strcmp(name, "keycreate"))
5295
		error = current_has_perm(p, PROCESS__SETKEYCREATE);
5296
	else if (!strcmp(name, "sockcreate"))
5297
		error = current_has_perm(p, PROCESS__SETSOCKCREATE);
L
Linus Torvalds 已提交
5298
	else if (!strcmp(name, "current"))
5299
		error = current_has_perm(p, PROCESS__SETCURRENT);
L
Linus Torvalds 已提交
5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311
	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);
5312 5313 5314 5315 5316 5317
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
			if (!capable(CAP_MAC_ADMIN))
				return error;
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5318 5319 5320 5321
		if (error)
			return error;
	}

D
David Howells 已提交
5322 5323 5324 5325
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5326 5327 5328
	/* 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
5329
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
5330 5331
	   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
5332 5333
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
5334
		tsec->exec_sid = sid;
D
David Howells 已提交
5335
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
5336
		tsec->create_sid = sid;
D
David Howells 已提交
5337
	} else if (!strcmp(name, "keycreate")) {
5338 5339
		error = may_create_key(sid, p);
		if (error)
D
David Howells 已提交
5340
			goto abort_change;
5341
		tsec->keycreate_sid = sid;
D
David Howells 已提交
5342
	} else if (!strcmp(name, "sockcreate")) {
5343
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
5344 5345
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
5346
		if (sid == 0)
D
David Howells 已提交
5347 5348 5349 5350
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
5351
		if (!current_is_single_threaded()) {
D
David Howells 已提交
5352 5353 5354
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
5355
		}
L
Linus Torvalds 已提交
5356 5357 5358

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5359
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
5360
		if (error)
D
David Howells 已提交
5361
			goto abort_change;
L
Linus Torvalds 已提交
5362 5363 5364

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
D
David Howells 已提交
5365
		ptsid = 0;
L
Linus Torvalds 已提交
5366
		task_lock(p);
5367
		tracer = ptrace_parent(p);
D
David Howells 已提交
5368 5369 5370 5371 5372 5373 5374
		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
5375
			if (error)
D
David Howells 已提交
5376
				goto abort_change;
L
Linus Torvalds 已提交
5377 5378
		}

D
David Howells 已提交
5379 5380 5381 5382 5383 5384 5385
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
5386
	return size;
D
David Howells 已提交
5387 5388 5389 5390

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
5391 5392
}

5393 5394 5395 5396 5397
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

5398
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5399 5400 5401 5402
{
	return security_context_to_sid(secdata, seclen, secid);
}

5403 5404
static void selinux_release_secctx(char *secdata, u32 seclen)
{
5405
	kfree(secdata);
5406 5407
}

5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433
/*
 *	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;
}
5434 5435
#ifdef CONFIG_KEYS

D
David Howells 已提交
5436
static int selinux_key_alloc(struct key *k, const struct cred *cred,
5437
			     unsigned long flags)
5438
{
D
David Howells 已提交
5439
	const struct task_security_struct *tsec;
5440 5441 5442 5443 5444 5445
	struct key_security_struct *ksec;

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

D
David Howells 已提交
5446 5447 5448
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
5449
	else
D
David Howells 已提交
5450
		ksec->sid = tsec->sid;
5451

5452
	k->security = ksec;
5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464
	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
5465 5466
				  const struct cred *cred,
				  key_perm_t perm)
5467 5468 5469
{
	struct key *key;
	struct key_security_struct *ksec;
5470
	u32 sid;
5471 5472 5473 5474 5475 5476 5477

	/* 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
5478
	sid = cred_sid(cred);
5479 5480 5481 5482 5483

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

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5484 5485
}

5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499
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;
}

5500 5501
#endif

L
Linus Torvalds 已提交
5502
static struct security_operations selinux_ops = {
5503 5504
	.name =				"selinux",

5505
	.ptrace_access_check =		selinux_ptrace_access_check,
5506
	.ptrace_traceme =		selinux_ptrace_traceme,
L
Linus Torvalds 已提交
5507
	.capget =			selinux_capget,
D
David Howells 已提交
5508
	.capset =			selinux_capset,
L
Linus Torvalds 已提交
5509 5510 5511 5512 5513 5514 5515 5516
	.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,

5517 5518 5519
	.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
5520 5521 5522 5523 5524
	.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,
5525
	.sb_remount =			selinux_sb_remount,
5526
	.sb_kern_mount =		selinux_sb_kern_mount,
5527
	.sb_show_options =		selinux_sb_show_options,
L
Linus Torvalds 已提交
5528 5529 5530
	.sb_statfs =			selinux_sb_statfs,
	.sb_mount =			selinux_mount,
	.sb_umount =			selinux_umount,
5531
	.sb_set_mnt_opts =		selinux_set_mnt_opts,
5532
	.sb_clone_mnt_opts =		selinux_sb_clone_mnt_opts,
5533 5534
	.sb_parse_opts_str = 		selinux_parse_opts_str,

L
Linus Torvalds 已提交
5535 5536 5537

	.inode_alloc_security =		selinux_inode_alloc_security,
	.inode_free_security =		selinux_inode_free_security,
5538
	.inode_init_security =		selinux_inode_init_security,
L
Linus Torvalds 已提交
5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556
	.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,
5557 5558 5559
	.inode_getsecurity =		selinux_inode_getsecurity,
	.inode_setsecurity =		selinux_inode_setsecurity,
	.inode_listsecurity =		selinux_inode_listsecurity,
5560
	.inode_getsecid =		selinux_inode_getsecid,
L
Linus Torvalds 已提交
5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573

	.file_permission =		selinux_file_permission,
	.file_alloc_security =		selinux_file_alloc_security,
	.file_free_security =		selinux_file_free_security,
	.file_ioctl =			selinux_file_ioctl,
	.file_mmap =			selinux_file_mmap,
	.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,

5574
	.dentry_open =			selinux_dentry_open,
5575

L
Linus Torvalds 已提交
5576
	.task_create =			selinux_task_create,
5577
	.cred_alloc_blank =		selinux_cred_alloc_blank,
5578
	.cred_free =			selinux_cred_free,
D
David Howells 已提交
5579
	.cred_prepare =			selinux_cred_prepare,
5580
	.cred_transfer =		selinux_cred_transfer,
5581 5582
	.kernel_act_as =		selinux_kernel_act_as,
	.kernel_create_files_as =	selinux_kernel_create_files_as,
5583
	.kernel_module_request =	selinux_kernel_module_request,
L
Linus Torvalds 已提交
5584 5585
	.task_setpgid =			selinux_task_setpgid,
	.task_getpgid =			selinux_task_getpgid,
5586
	.task_getsid =			selinux_task_getsid,
5587
	.task_getsecid =		selinux_task_getsecid,
L
Linus Torvalds 已提交
5588
	.task_setnice =			selinux_task_setnice,
5589
	.task_setioprio =		selinux_task_setioprio,
5590
	.task_getioprio =		selinux_task_getioprio,
L
Linus Torvalds 已提交
5591 5592 5593
	.task_setrlimit =		selinux_task_setrlimit,
	.task_setscheduler =		selinux_task_setscheduler,
	.task_getscheduler =		selinux_task_getscheduler,
5594
	.task_movememory =		selinux_task_movememory,
L
Linus Torvalds 已提交
5595 5596
	.task_kill =			selinux_task_kill,
	.task_wait =			selinux_task_wait,
5597
	.task_to_inode =		selinux_task_to_inode,
L
Linus Torvalds 已提交
5598 5599

	.ipc_permission =		selinux_ipc_permission,
5600
	.ipc_getsecid =			selinux_ipc_getsecid,
L
Linus Torvalds 已提交
5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617

	.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,

5618 5619
	.sem_alloc_security =		selinux_sem_alloc_security,
	.sem_free_security =		selinux_sem_free_security,
L
Linus Torvalds 已提交
5620 5621 5622 5623
	.sem_associate =		selinux_sem_associate,
	.sem_semctl =			selinux_sem_semctl,
	.sem_semop =			selinux_sem_semop,

5624
	.d_instantiate =		selinux_d_instantiate,
L
Linus Torvalds 已提交
5625

5626 5627
	.getprocattr =			selinux_getprocattr,
	.setprocattr =			selinux_setprocattr,
L
Linus Torvalds 已提交
5628

5629
	.secid_to_secctx =		selinux_secid_to_secctx,
5630
	.secctx_to_secid =		selinux_secctx_to_secid,
5631
	.release_secctx =		selinux_release_secctx,
5632 5633 5634
	.inode_notifysecctx =		selinux_inode_notifysecctx,
	.inode_setsecctx =		selinux_inode_setsecctx,
	.inode_getsecctx =		selinux_inode_getsecctx,
5635

5636
	.unix_stream_connect =		selinux_socket_unix_stream_connect,
L
Linus Torvalds 已提交
5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650 5651 5652
	.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
5653 5654
	.socket_getpeersec_stream =	selinux_socket_getpeersec_stream,
	.socket_getpeersec_dgram =	selinux_socket_getpeersec_dgram,
L
Linus Torvalds 已提交
5655 5656
	.sk_alloc_security =		selinux_sk_alloc_security,
	.sk_free_security =		selinux_sk_free_security,
5657
	.sk_clone_security =		selinux_sk_clone_security,
5658
	.sk_getsecid =			selinux_sk_getsecid,
5659 5660 5661
	.sock_graft =			selinux_sock_graft,
	.inet_conn_request =		selinux_inet_conn_request,
	.inet_csk_clone =		selinux_inet_csk_clone,
5662
	.inet_conn_established =	selinux_inet_conn_established,
5663 5664 5665
	.secmark_relabel_packet =	selinux_secmark_relabel_packet,
	.secmark_refcount_inc =		selinux_secmark_refcount_inc,
	.secmark_refcount_dec =		selinux_secmark_refcount_dec,
5666
	.req_classify_flow =		selinux_req_classify_flow,
5667 5668 5669
	.tun_dev_create =		selinux_tun_dev_create,
	.tun_dev_post_create = 		selinux_tun_dev_post_create,
	.tun_dev_attach =		selinux_tun_dev_attach,
5670 5671 5672 5673 5674

#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
5675
	.xfrm_policy_delete_security =	selinux_xfrm_policy_delete,
5676 5677
	.xfrm_state_alloc_security =	selinux_xfrm_state_alloc,
	.xfrm_state_free_security =	selinux_xfrm_state_free,
C
Catherine Zhang 已提交
5678
	.xfrm_state_delete_security =	selinux_xfrm_state_delete,
5679
	.xfrm_policy_lookup =		selinux_xfrm_policy_lookup,
5680 5681
	.xfrm_state_pol_flow_match =	selinux_xfrm_state_pol_flow_match,
	.xfrm_decode_session =		selinux_xfrm_decode_session,
L
Linus Torvalds 已提交
5682
#endif
5683 5684

#ifdef CONFIG_KEYS
5685 5686 5687
	.key_alloc =			selinux_key_alloc,
	.key_free =			selinux_key_free,
	.key_permission =		selinux_key_permission,
5688
	.key_getsecurity =		selinux_key_getsecurity,
5689
#endif
5690 5691 5692 5693 5694 5695 5696

#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
5697 5698 5699 5700
};

static __init int selinux_init(void)
{
5701 5702 5703 5704 5705
	if (!security_module_enable(&selinux_ops)) {
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
5706 5707 5708 5709 5710 5711 5712 5713
	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
5714
	cred_init_security();
L
Linus Torvalds 已提交
5715

5716 5717
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

5718 5719
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
5720
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
5721 5722
	avc_init();

5723
	if (register_security(&selinux_ops))
L
Linus Torvalds 已提交
5724 5725
		panic("SELinux: Unable to register with kernel.\n");

5726
	if (selinux_enforcing)
5727
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5728
	else
5729
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5730

L
Linus Torvalds 已提交
5731 5732 5733
	return 0;
}

5734 5735 5736 5737 5738
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
5739 5740
void selinux_complete_init(void)
{
5741
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
5742 5743

	/* Set up any superblocks initialized prior to the policy load. */
5744
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5745
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
5746 5747 5748 5749 5750 5751
}

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

5752
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
5753

5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767
static struct nf_hook_ops selinux_ipv4_ops[] = {
	{
		.hook =		selinux_ipv4_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5768 5769 5770 5771 5772 5773 5774
	},
	{
		.hook =		selinux_ipv4_output,
		.owner =	THIS_MODULE,
		.pf =		PF_INET,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
5775
	}
L
Linus Torvalds 已提交
5776 5777 5778 5779
};

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

5780 5781 5782 5783 5784 5785 5786 5787 5788 5789 5790 5791 5792 5793 5794
static struct nf_hook_ops selinux_ipv6_ops[] = {
	{
		.hook =		selinux_ipv6_postroute,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
		.owner =	THIS_MODULE,
		.pf =		PF_INET6,
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	}
L
Linus Torvalds 已提交
5795 5796 5797 5798 5799 5800 5801 5802 5803 5804
};

#endif	/* IPV6 */

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

	if (!selinux_enabled)
		goto out;
5805 5806 5807

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

5808 5809 5810
	err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
L
Linus Torvalds 已提交
5811 5812

#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5813 5814 5815
	err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
	if (err)
		panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
L
Linus Torvalds 已提交
5816
#endif	/* IPV6 */
5817

L
Linus Torvalds 已提交
5818 5819 5820 5821 5822 5823 5824 5825 5826
out:
	return err;
}

__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
5827
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
5828

5829
	nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
L
Linus Torvalds 已提交
5830
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5831
	nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
L
Linus Torvalds 已提交
5832 5833 5834 5835
#endif	/* IPV6 */
}
#endif

5836
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5837 5838 5839 5840 5841

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

5842
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
5843 5844

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5845 5846
static int selinux_disabled;

L
Linus Torvalds 已提交
5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861
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;
5862
	selinux_enabled = 0;
L
Linus Torvalds 已提交
5863

5864
	reset_security_ops();
L
Linus Torvalds 已提交
5865

5866 5867 5868
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
5869 5870 5871 5872 5873 5874 5875 5876 5877
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif