DPAPI Configuration

The component accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

DPAPI Configuration Settings

ProtectionFlags: Used to specify additional options.

Additional options are available to restrict or change the behavior of the protect and unprotect operations.

By default no additional settings are specified (the value is 0). You may set this property to the binary 'OR' of one or more of the following values:


1 (0x1)	CRYPTPROTECT_UI_FORBIDDEN	This flag is used for remote situations where presenting a user interface (UI) is not an option. When this flag is set and a UI is specified for either the protect or unprotect operation, the operation fails.
4 (0x4)	CRYPTPROTECT_LOCAL_MACHINE	When this flag is set, it associates the data encrypted with the current computer instead of with an individual user. This is only applicable when calling Protect.
8 (0x8)	CRYPTPROTECT_CRED_SYNC	When this flag is used, no data is actually protected. Instead all MasterKeys are queried from disk, which will cause re-encryption in memory, presumably under a changed password. This is only applicable when calling Protect.
16 (0x10)	CRYPTPROTECT_AUDIT	This flag causes DPAPI to generate an audit when this data is protected or unprotected. This is only applicable when calling Protect.
64 (0x40)	CRYPTPROTECT_VERIFY_PROTECTION	If the protected data blob would be better protected under a new call to the internal protect function and this call succeeds, then GetLastError will return a CRYPT_I_NEW_PROTECTION_REQUIRED status code. This is only applicable when calling Unprotect.
536870912 (0x20000000)	CRYPTPROTECT_SYSTEM	If data was protected with this flag set, then this flag must be set to unprotect the data.

CloseInputStreamAfterProcessing: Determines whether or not the input stream is closed after processing.

Determines whether or not the input stream set by SetInputStream is closed after processing is complete. The default value is True.

CloseOutputStreamAfterProcessing: Determines whether or not the output stream is closed after processing.

Determines whether or not the output stream set by SetOutputStream is closed after processing is complete. The default value is True.

Base Configuration Settings


	GUIAvailable: Tells the component whether or not a message loop is available for processing events. In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The component will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation. In some non-GUI applications an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GuiAvailable to false will ensure that the component does not attempt to process external events.
	UseBackgroundThread: Whether threads created by the component are background threads. If set to True, when the component creates a thread the thread's IsBackground property will be explicitly set to True. By default this setting is False.
	UseManagedSecurityAPI: Tells the component whether or not to use the system security libraries or a managed implementation. By default the component will use the system security libraries to perform cryptographic functions. This means calls to unmanaged code will be made. In certain environments this is not desirable. To use a completely managed security implementation set this setting to True. Setting this to True tells the component to use the internal managed implementation instead of using the system's security API. Note that when this value is set the product's system dll is no longer required as a reference, as all unmanaged code is stored in this file.