WMRMChallenge.Challenge

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WMRMChallenge.Challenge

The Challenge property specifies and retrieves the license request.

Syntax

  WMRMChallenge
  .Challenge
  
  =
  
  String
String
  
  =
  
  Challenge

Parameters

This property takes no parameters.

Return Values

If the property succeeds, it returns a String containing the challenge from the consumer. If it fails, it returns a number in the error object.

Return code Description
0x80004005 An unspecified error occurred.
0x80070057 The specified parameter is not valid.

Remarks

A challenge contains the following information:

  • Version 10 content header (backward compatible with version 7.1).
    • The key ID used to create a key.
    • An optional content ID to uniquely identify the encrypted content.
    • Optional attributes that identify the content.
    • A URL identifying the Internet address of the license issuer.
  • Information about the consumer's computer.
    • An encrypted client ID.
    • The version of Windows Media Rights Manager on the consumer's computer.
    • The individualized version number on the consumer's computer.
  • Action list indicating the rights requested by the consumer.
  • An optional Windows Media Rights Manager version 1 challenge This is included because versions of the player earlier than version 7 cannot process version 7 or later licenses. However, it is not included when a license is predelivered.

Example Code

' Assume that the content packager has sent encrypted content and 
' a header to a consumer. The consumer's computer determines that 
' a license is needed and 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.
'
' For more information about the header, see the WMRMHeader object.


' Declare variables and objects.

    Dim sHeader, sClientInfo, sPubKey, lResult, dwActionCnt
    Dim sLicRequest, lIndex, sVerClient, sVerSecurity, sAppSecurity
    Dim sAction()
    Dim HeaderObj
    Dim ChallengeObj

' Create objects.

    Set HeaderObj = Server.CreateObject("Wmrmobjs.WMRMHeader")
    Set ChallengeObj = Server.CreateObject("Wmrmobjs.WMRMChallenge")
  
' 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

' 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

' Retrieve attributes from the client.

    sVerClient = ChallengeObj.ClientAttribute("CLIENTVERSION" )
        ' Perform actions based on the DRM component
        ' version installed on the client computer.

    sVerSecurity = ChallengeObj.ClientAttribute("SECURITYVERSION")
        ' Perform actions based on the security version number.

    sAppSecurity  = ChallengeObj.ClientAttribute("APPSECURITY")
        ' Perform actions based on the security level of the 
        ' application on which the Windows Media file is to
        ' be played.

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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