WMRMLicGen.SetKey

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WMRMLicGen.SetKey

The SetKey method specifies the encoded key to use in the license.

Syntax

  WMRMLicGen
  .SetKey(
  bstrType
  , bstrKey)

Parameters

bstrType

[in] String containing the type of the algorithm used to store the key in the license. This parameter is provided so that you can make changes later to accommodate longer keys. This can also be an empty string. By default, the value is "MSDRM."

bstrKey

[in] String containing the encoded key to be used in the license. Use the WMRMKeys object to generate the key.

Return Values

If the method succeeds, it returns S_OK. If it fails, it returns a number in the error object.

Return code Description
0x80048001 A parameter is not valid.
0x80048002 Memory cannot be allocated.
0x80048003 The object cannot be initialized.
0x80048004 An internal error occurred.
0x8004800C The specified key is not valid.
0x8004800D The key cannot be encoded.
0x80048011 The encrypting algorithm is not supported.

Example Code

' Assume that the content packager has sent encrypted content and 
' a header to a consumer. The client computer posts a challenge to 
' the license issuer. The challenge contains the header sent by the 
' content packager, actions requested by the client, and information 
' about the client computer. To issue a license, perform the 
' following steps.
'

' Declare variables and objects.

    Dim sHeader, sClientInfo, sPubKey, lResult, dwActionCnt
    Dim sLicRequest, lIndex, sRights, sKeyID, sSeed, sKey 
    Dim varCategory, varVersion, sLicense, sLicResponse
    Dim strRevinfo, ContainsRevinfo, strClientCRLs
    Dim sAction
    Dim HeaderObj
    Dim ChallengeObj
    Dim Rights Obj
    Dim LicGenObj
    Dim ResponseObj

' Create objects.

    Set HeaderObj = Server.CreateObject("Wmrmobjs.WMRMHeader")
    Set ChallengeObj = Server.CreateObject("Wmrmobjs.WMRMChallenge")
    Set RightsObj = Server.CreateObject("Wmrmobjs.WMRMRights")
    Set LicGenObj = Server.CreateObject("Wmrmobjs.WMRMLicGen")
    Set KeysObj = Server.CreateObject("Wmrmobjs.WMRMKeys")
    Set ResponseObj = Server.CreateObject("Wmrmobjs.WMRMResponse")
  
' Retrieve the license request from the client computer.

    sLicRequest = request.Form("challenge")

' Set the license request into the WMRMChallenge object.

    ChallengeObj.Challenge = sLicRequest

' Retrieve the header from the challenge.

    sHeader = ChallengeObj.Header

' Check for revocation information.

    strRevinfo = ChallengeObj.RevInfo
    ContainsRevinfo = ChallengeObj.RevInfoPresent

' Set the header into the WMRMHeader object.

    HeaderObj.Header = sHeader

' Verify the header with the public key created by the content
' packager.

    lResult = HeaderObj.Verify(sPubKey)
    if (lResult = 0) then
        ' The header has been corrupted.
    end if

' Retrieve the client information section of the challenge.

    sClientInfo = ChallengeObj.ClientInfo

' Define the additional rights to be granted to the consumer.

    RightsObj.Reset
    RightsObj.AllowBackupRestore = True
    RightsObj.AllowCopy = False
    RightsObj.BeginDate = "#20050101Z#"
    RightsObj.ExpirationDate = "#20051231Z#"
    RightsObj.DisableOnClockRollback = True
    
' Retrieve the string containing the defined rights, and set 
' the rights into the license.

    sRights = RightsObj.GetAllRights()
    LicGenObj.Rights = sRights

' Set the client information into the license.

    LicGenObj.ClientInfo = sClientInfo

' Check the individualized version of Windows Media Rights Manager
' running on the client computer.

    LicGenObj.GetClientVersion varCategory, varVersion
    Select Case varCategory
      Case 0
          ' Client is not individualized.
      case 1
          ' Client is individualized.
      Case Else
          ' Invalid client category.
    End Select

' Call the BindToPubKey property to send the client a public
' key used to verify the license. When the license contains a 
' public key, Windows Media Rights Manager on the client computer 
' verifies the license. The public key is included in the certificate
' sent to the license issuer by Windows Media License Service.

    LicGenObj.BindToPubKey = sPubKey 

' Set the name of the licensing server into the license.

    LicGenObj.Attribute("Author") = "name of the author"
    LicGenObj.Attribute("ContentDistributor") = "name of the distributor"
    LicGenObj.Attribute("ContentType") = "type of content distributed"
    LicGenObj.Attribute("Title") = "title of the content"

' Set the priority into the license. 

    LicGenObj.Priority = 10

' Retrieve the key ID from the header, and set it into the license.

    sKeyID = HeaderObj.KeyID
    LicGenObj.KeyID = sKeyID

' Use the key ID and your stored license key seed to create the 
' key, and set the key into the license. The license key seed is a
' shared secret between the content packager and the license issuer.

    KeysObj.KeyID = sKeyID
    KeysObj.Seed = sSeed
    sKey = KeysObj.GenerateKey()
    LicGenObj.SetKey("MSDRM", sKey)

' Get the certificate revocation lists that are supported by the client.
    strClientCRLs = LicGenObj.SupportedCRLS

' Create a license.

    sLicense = LicGen.GetLicenseToDeliver()

' Add this license to the license response.

    Call ResponseObj.AddLicense("2.0.0.0", sLicense)
    Call ResponseObj.AddRevocationData(strRevinfo, strClientCRLs, ContainsRevinfo)

' Retrieve a string containing the license response.

    sLicResponse = Response.GetLicenseResponse()

Requirements

Version: Windows Media Rights Manager 7 SDK or later

Reference: wmrmobjs 1.0 Type Library

Library: wmrmobjs.dll

Platform: Windows Server 2003

See Also

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