crypto/weakcryptospi/source/random/randomshim.cpp
author Mikko Sunikka <mikko.sunikka@nokia.com>
Fri, 06 Nov 2009 13:21:00 +0200
changeset 19 cd501b96611d
child 41 9b5a3a9fddf8
permissions -rw-r--r--
Revision: 200945 Kit: 200945
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
19
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     1
/*
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     2
* Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     3
* All rights reserved.
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     4
* This component and the accompanying materials are made available
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     5
* under the terms of the License "Eclipse Public License v1.0"
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     6
* which accompanies this distribution, and is available
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     7
* at the URL "http://www.eclipse.org/legal/epl-v10.html".
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     8
*
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
     9
* Initial Contributors:
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    10
* Nokia Corporation - initial contribution.
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    11
*
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    12
* Contributors:
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    13
*
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    14
* Description: 
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    15
* random shim implementation
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    16
* random shim implementation
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    17
*
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    18
*/
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    19
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    20
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    21
/**
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    22
 @file
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    23
*/
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    24
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    25
#include "randomshim.h"
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    26
#include <cryptospi/cryptospidef.h>
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    27
#include <cryptospi/cryptorandomapi.h>
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    28
#include <cryptospi/plugincharacteristics.h>
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    29
#include "keys.h"
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    30
#include <e32debug.h>
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    31
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    32
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    33
using namespace CryptoSpi;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    34
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    35
_LIT(KRandomFail, "Cannot obtain randomness");
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    36
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    37
//
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    38
// Random shim implementation
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    39
//
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    40
CRandomShim* CRandomShim::NewL()
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    41
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    42
	CRandomShim* self = CRandomShim::NewLC();
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    43
	CleanupStack::Pop();
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    44
	return self;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    45
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    46
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    47
CRandomShim* CRandomShim::NewLC()
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    48
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    49
	CRandomShim* self = new(ELeave) CRandomShim();
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    50
	CleanupStack::PushL(self);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    51
	self->ConstructL();
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    52
	return self;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    53
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    54
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    55
void CRandomShim::GenerateBytesL(TDes8& aDest)
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    56
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    57
	iRandomImpl->GenerateRandomBytesL(aDest);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    58
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    59
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    60
CRandomShim::CRandomShim()
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    61
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    62
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    63
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    64
CRandomShim::~CRandomShim()
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    65
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    66
	delete iRandomImpl;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    67
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    68
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    69
void CRandomShim::ConstructL()
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    70
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    71
	CRandomFactory::CreateRandomL(iRandomImpl, KRandomUid, NULL);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    72
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    73
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    74
/**
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    75
 * @deprecated Use RandomL() instead
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    76
 * @panic This function can panic under low memory conditions
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    77
 * See PDEF097319: TRandom::Random panics during OOM
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    78
 * This method is preserved only for BC reasons
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    79
 */
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    80
void TRandomShim::Random(TDes8& aDest)
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    81
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    82
	CRandomShim* rand = NULL;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    83
	TRAPD(ret, rand = CRandomShim::NewL());
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    84
	if (ret != KErrNone)
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    85
		{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    86
		User::Panic(KRandomFail, ret);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    87
		}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    88
	TRAPD(ret2, rand->GenerateBytesL(aDest));
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    89
	delete rand;
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    90
	if (ret2 != KErrNone)
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    91
		{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    92
		// this method can't leave so the cleanup stack can't be used (because of PushL()) 
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    93
		// so we just delete the randon shim here if GenerateBytesL() leaves
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    94
		User::Panic(KRandomFail, ret);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    95
		}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    96
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    97
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    98
void TRandomShim::RandomL(TDes8& aDest)
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
    99
	{
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   100
	CRandomShim* rand = CRandomShim::NewL();
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   101
	CleanupStack::PushL(rand);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   102
	rand->GenerateBytesL(aDest);
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   103
	CleanupStack::PopAndDestroy(rand); // Use a singleton, avoid new overhead?
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   104
	}
cd501b96611d Revision: 200945
Mikko Sunikka <mikko.sunikka@nokia.com>
parents:
diff changeset
   105