SetCryptFilterConfiguration

Security, Attachments

Description

Atomically selects which PDF object classes use the document standard crypt filter during the next encryption operation

Syntax

Delphi

Function TPDFlib.SetCryptFilterConfiguration(EncryptStrings, EncryptStreams, EncryptEmbeddedFiles: Integer): Integer;

DLL

Function DLSetCryptFilterConfiguration(InstanceID, EncryptStrings, EncryptStreams, EncryptEmbeddedFiles: Integer): Integer; Stdcall;

ActiveX

Function PDFlib::SetCryptFilterConfiguration(EncryptStrings As Long, EncryptStreams As Long, EncryptEmbeddedFiles As Long) As Long

Parameters

EncryptStrings	`1` selects the standard filter for `/StrF`; `0` selects `Identity`
EncryptStreams	`1` selects the standard filter for ordinary streams through `/StmF`; `0` selects `Identity`
EncryptEmbeddedFiles	`1` selects the standard filter for embedded-file streams through `/EFF`; `0` selects `Identity`

Return values

0	A value is not zero or one, all three targets are disabled, no document is selected, or encryption has already begun
1	The complete target configuration was accepted

Remarks

The default is 1, 1, 1, which encrypts strings, ordinary streams, and embedded files

Selective configurations require AES-128, AES-256, AES-256 Acrobat X, or AES-256-GCM and are applied consistently to password, public-key, and fingerprint encryption

The established SetEncryptEmbeddedFilesOnly method maps 1 to 0, 0, 1 and maps 0 back to 1, 1, 1

Example

PDF.SetCryptFilterConfiguration(0, 1, 0);
PDF.Encrypt('owner-password', 'user-password', 2, Permissions);
PDF.SaveToFile('selective-encryption.pdf');