WriteProtection.CryptographicProviderTypeExtensibility Property

Definition

Namespace:

DocumentFormat.OpenXml.Wordprocessing

Assembly:

DocumentFormat.OpenXml.dll

Package:

DocumentFormat.OpenXml v3.0.1

Cryptographic Provider Type Extensibility

Represents the following attribute in the schema: w:cryptProviderTypeExt

public DocumentFormat.OpenXml.HexBinaryValue? CryptographicProviderTypeExtensibility { get; set; }

member this.CryptographicProviderTypeExtensibility : DocumentFormat.OpenXml.HexBinaryValue with get, set

Public Property CryptographicProviderTypeExtensibility As HexBinaryValue

Property Value

HexBinaryValue

Returns StringValue.

Remarks

The following information from the ECMA International Standard ECMA-376 can be useful when working with this class.

Specifies that a cryptographic provider type which was not defined by the Office Open XML Standard has been used to generate the hash value stored with this document.

This value, when present, shall be interpreted based on the value of the cryptProviderTypeExtSource attribute in order to determine the provider type used, which shall be application defined. This extensibility affords the fact that with exponentially increasing computing power, documents created in the future will likely need to use as yet undefined cryptographic provider types in order to remain secure.

If this value is present, the cryptProviderType attribute value shall be ignored in favor of the provider type defined by this attribute.

Consider a WordprocessingML document with the following information stored in one of its protection elements:

<w:… w:cryptProviderTypeExt="00A5691D"   
  w:cryptProvideTypeExtSource="Contoso"  
  w:hash="9oN7nWkCAyEZib1RomSJTjmPpCY=" />  

The cryptProviderTypeExt attribute value of 00A5691D specifies that the provider type associated with hex code A5691D shall be used as defined by the Contoso application.

The possible values for this attribute are defined by the ST_LongHexNumber simple type.