xnu-1699.22.81.tar.gz

[apple/xnu.git] / iokit / Kernel / i386 / IOKeyStoreHelper.cpp

/*
 * Copyright (c) 2010 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#include <sys/cdefs.h>
#include <stdbool.h>

#include <IOKit/assert.h>
#include <IOKit/system.h>
#include <IOKit/IOLib.h>
#include <IOKit/IOMemoryDescriptor.h>
#include <IOKit/IOKitDebug.h>

__BEGIN_DECLS

#include <pexpert/pexpert.h>

static volatile UInt32 alreadyFetched = 0;
static IOMemoryDescriptor * newData;

IOMemoryDescriptor *
IOGetBootKeyStoreData(void);
void
IOSetKeyStoreData(IOMemoryDescriptor * data);

__END_DECLS

#if 1
#define DEBG(fmt, args...)  	{ kprintf(fmt, ## args); }
#else
#define DEBG(fmt, args...)  	{}
#endif

void
IOSetKeyStoreData(IOMemoryDescriptor * data)
{
    newData = data;
    alreadyFetched = 0;
}

IOMemoryDescriptor *
IOGetBootKeyStoreData(void)
{
  IOMemoryDescriptor *memoryDescriptor;
  boot_args *args = (boot_args *)PE_state.bootArgs;
  IOOptionBits options;
  IOAddressRange ranges;

  if (!OSCompareAndSwap(0, 1, &alreadyFetched))
    return (NULL);

  if (newData)
  {
    IOMemoryDescriptor * data = newData;
    newData = NULL;
    return (data);
  }  

  DEBG("%s: data at address %u size %u\n", __func__,
       args->keyStoreDataStart,
       args->keyStoreDataSize);

  if (args->keyStoreDataStart == 0)
    return (NULL);

  ranges.address = args->keyStoreDataStart;
  ranges.length = args->keyStoreDataSize;

  options = kIODirectionInOut | kIOMemoryTypePhysical64;
  
  memoryDescriptor = IOMemoryDescriptor::withOptions(&ranges,
						     1,
						     0,
						     NULL,
						     options);

  DEBG("%s: memory descriptor %p\n", __func__, memoryDescriptor);

  return memoryDescriptor;
}