<?xml version="1.0" encoding="utf-8"?>

<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

<!-- This component and the accompanying materials are made available under the terms of the License 

"Eclipse Public License v1.0" which accompanies this distribution, 

and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

<!-- Initial Contributors:

    Nokia Corporation - initial contribution.

Contributors: 

-->

<!DOCTYPE task

  PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">

<task id="GUID-EFF8D1A1-00D5-5F96-8285-414DC0044AB8" xml:lang="en"><title>Setting

Use Policies</title><shortdesc>A use policy denotes the security check required to use the key.

The policy can be set to check capabilities or the Secure ID associated with

the calling process. The calling process should have a <codeph>WriteUserData</codeph> capability. </shortdesc><prolog><metadata><keywords/></metadata></prolog><taskbody>

for a key:</p></context>

session using an <codeph>RFs</codeph> object. </cmd>

</step>

<info>Create an object of type CUnifiedKeyStore using <xref href="GUID-818689D6-EB99-382E-A435-D9C6C5D464DE.dita#GUID-818689D6-EB99-382E-A435-D9C6C5D464DE/GUID-C7A96153-4179-3B3F-878D-1EAA64A98D39"><apiname>CUnifiedKeyStore::NewL()</apiname></xref> or <xref href="GUID-818689D6-EB99-382E-A435-D9C6C5D464DE.dita#GUID-818689D6-EB99-382E-A435-D9C6C5D464DE/GUID-217FBB3B-CEF5-36F2-A612-EDDA0982053C"><apiname>CUnifiedKeyStore::NewLC()</apiname></xref>. </info>

</step>

<info>Initialise the member functions and keystore using the asynchronous

function <xref href="GUID-818689D6-EB99-382E-A435-D9C6C5D464DE.dita#GUID-818689D6-EB99-382E-A435-D9C6C5D464DE/GUID-6C5D732C-1FD1-3EF0-AC90-87690F891B8D"><apiname>CUnifiedKeyStore::Initialize()</apiname></xref>. </info>

</step>

<step id="GUID-B1DD3DB8-90D9-52F7-96B5-B2AD5AE3E1F8"><cmd/>

<info>List all keys in the keystore using the <xref href="GUID-818689D6-EB99-382E-A435-D9C6C5D464DE.dita#GUID-818689D6-EB99-382E-A435-D9C6C5D464DE/GUID-8B22E1BC-D779-32DC-9C0A-CA37E4C0A81B"><apiname>CUnifiedKeyStore::List()</apiname></xref> function.

Retrieve the handle of the key for which the use policy needs to be set. </info>

</step>

<info>Set the use policy for the key using the <xref href="GUID-818689D6-EB99-382E-A435-D9C6C5D464DE.dita#GUID-818689D6-EB99-382E-A435-D9C6C5D464DE/GUID-CC8814B6-569C-3426-A319-BFB631211B07"><apiname>CUnifiedKeyStore::SetUsePolicy()</apiname></xref> function. </info>

</step>

</steps>

RFs iFs;

CleanupClosePushL(&iFs);

...

// Initialise the keystore and member functions

CUnifiedKeyStore* keyStore = CUnifiedKeyStore::NewL(fs);

keyStore->Initialize(iStatus); //iStatus is a TRequestStatus object

...

// Retrieve the handle of the key for which use policy has to be set

TCTKeyAttributeFilter  filter.iUsage = EPKCS15UsageAll;

RPointerArray<CCTKeyInfo> iKeys; // This variable will contain the result of the set use policy operation

keyStore->List(iKeys, filter, iStatus);

...

// Retrieve the key handle of the appropriate key

_LIT(KLabel,”keylabel”);

// Select the key with the label you are looking for

TInt keyIndex;

for (TInt j = 0; j < iKeys.Count(); j++)

    {

    if (iKeys[j]->Label() == KLabel) 

        {

        keyIndex = j;

        break;

        }

    }

...

// Set the use policy

TSecurityPolicy usePolicy;

TUint secureId = 0x101FFFFF;

TCapability caps[3];

caps[0] = ECapabilityWriteUserData;

caps[1] = ECapabilityDRM;

caps[2] = ECapabilityReadUserData;

usePolicy = TSecurityPolicy(TSecureId(secureId), caps[0], caps[1], caps[2]);

keyStore->SetUsePolicy(*iKeys, usePolicy, iStatus);

// Clean up

CleanupStack::PopAndDestroy(); // iFs</codeblock> </example>

</taskbody><related-links>

<link href="GUID-60141F31-6061-5C65-809D-FE7A4F8414F7.dita"><linktext>Set Management

Policies</linktext></link>

</related-links></task>