/* keyctl.c: userspace keyctl operations
*
* Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/syscalls.h>
#include <linux/keyctl.h>
#include <linux/fs.h>
#include <linux/capability.h>
#include <linux/string.h>
#include <linux/err.h>
#include <linux/vmalloc.h>
#include <linux/security.h>
#include <asm/uaccess.h>
#include "internal.h"
static int key_get_type_from_user(char *type,
const char __user *_type,
unsigned len)
{
int ret;
ret = strncpy_from_user(type, _type, len);
if (ret < 0)
return -EFAULT;
if (ret == 0 || ret >= len)
return -EINVAL;
if (type[0] == '.')
return -EPERM;
type[len - 1] = '\0';
return 0;
}
/*****************************************************************************/
/*
* extract the description of a new key from userspace and either add it as a
* new key to the specified keyring or update a matching key in that keyring
* - the keyring must be writable
* - returns the new key's serial number
* - implements add_key()
*/
asmlinkage long sys_add_key(const char __user *_type,
const char __user *_description,
const void __user *_payload,
size_t plen,
key_serial_t ringid)
{
key_ref_t keyring_ref, key_ref;
char type[32], *description;
void *payload;
long ret;
bool vm;
ret = -EINVAL;
if (plen > 1024 * 1024 - 1)
goto error;
/* draw all the data into kernel space */
ret = key_get_type_from_user(type, _type, sizeof(type));
if (ret < 0)
goto error;
description = strndup_user(_description, PAGE_SIZE);
if (IS_ERR(description)) {
ret = PTR_ERR(description);
goto error;
}
/* pull the payload in if one was supplied */
payload = NULL;
vm = false;
if (_payload) {
ret = -ENOMEM;
payload = kmalloc(plen, GFP_KERNEL);
if 