WMRMHeader.SetCheckSum

The SetCheckSum method specifies the checksum used for key verification.

Syntax

WMRMHeader.SetCheckSum(bstrKey)

Parameters

bstrKey

[in] String containing the symmetric key.

Return Values

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

Remarks

The checksum is used to verify that the key delivered in the license is the same as the key used to encrypt content.

Example Code

' Declare variables and objects.

    Dim sKID, sCID, sSeed, sKey, sHeader
    Dim sPrivKey, sPubKey
    Dim HeaderObj
    Dim KeysObj
    Dim ProtectObj

' Create objects.

    Set HeaderObj = Server.CreateObject("Wmrmobjs.WMRMHeader")
    Set KeysObj = Server.CreateObject("Wmrmobjs.WMRMKeys")
    Set ProtectObj = Server.CreateObject("Wmrmobjs.WMRMProtect")

' Create the key ID and content ID, and key. Set the key ID and ' the content ID into the header. Store the key in a secure manner.    sKID = KeysObj.GenerateKeyID()    sCID = KeysObj.GenerateKeyID()    KeysObj.KeyID = sKID    HeaderObj.KeyID = sKID    HeaderObj.ContentID = sCID'  Replace XXX with the license key seed.    sSeed = "XXX"    KeysObj.Seed = sSeed' Generate the key.    sKey = KeysObj.GenerateKey()

' Require individualization version 2.2.
' Version numbers change. Verify that this number is up to date.

    HeaderObj.IndividualizedVersion="2.2"

' Specify the URL of the license issuer, and set it into' the header.    sURL = "https://www.LicenseIssuer.com/getlicense.asp"    HeaderObj.LicenseAcqURL = sURL' Set name-value pairs describing the content into the header.    HeaderObj.Attribute("Author") = "name of the author"    HeaderObj.Attribute("ContentDistributor") = "name of the distributor"    HeaderObj.Attribute("ContentType") = "type of content distributed"    HeaderObj.Attribute("Title") = "title of the content"' Set the checksum.HeaderObj.SetCheckSum(sKey)

' Replace XXX with the packaging server's private key. 

    sPrivKey = "XXX"

' Sign the header.

    HeaderObj.Sign(sPrivKey)

' Retrieve the string containing the header.

    sHeader = HeaderObj.Header

' Set the header string into the WMRMProtect object.

    ProtectObj.Header = sHeader

' Set the key into the WMRMProtect object.

    ProtectObj.Key = sKey

' Specify the name of the file to be protected.

    ProtectObj.InputFile = "c:\input_file.wmv"

' Generate a protected file.

    ProtectObj.ProtectFile("c:\output_file_1.wmv")

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

• WMRMHeader Object