OnExternalDigestSign

Security and signatures, events

Description

Handles the final digest-signing operation for every externally configured sign process on a TPDFlib instance

Syntax

Delphi

Property OnExternalDigestSign: TPDFlibExternalDigestSignEvent Read FOnExternalDigestSign Write FOnExternalDigestSign;

Type TPDFlibExternalDigestSignEvent = Function(Sender: TObject; SignProcessID: Integer; Const Digest: AnsiString; DigestAlgorithm, SignatureAlgorithm: Integer; Var Signature: AnsiString): Boolean Of Object;

Parameters

Sender	The `TPDFlib` instance performing the operation
SignProcessID	The process whose signature is requested
Digest	Binary digest of the DER-encoded CMS authenticated-attributes set
DigestAlgorithm	Digest code selected by `SetSignProcessDigestAlgorithm`
SignatureAlgorithm	Raw signature format selected by `SetSignProcessExternalDigestSigner`
Signature	Set this output to the raw RSA signature, DER ECDSA signature, or P1363 ECDSA signature requested by `SignatureAlgorithm`

Return value

Return True only after Signature contains a complete result

Remarks

The event runs synchronously during EndSignProcessTo* and is not called during placeholder sizing

Exceptions, a false result, an empty signature, an oversized signature, or a signature that does not verify against the configured certificate cause the sign process to fail