FetchTimeStampToken

Digital signatures

Description

Obtains an RFC 3161 TimeStampToken for a digest from the configured authority.

Syntax

Delphi

Function TPDFlib.FetchTimeStampToken(Const MessageDigestHex: AnsiString): AnsiString;

Parameters

MessageDigestHex	Hex digest of the data being stamped. Its length must match the algorithm set by SetTimeStampOptions.

Return values

Token	The TimeStampToken as DER bytes.
Empty string	The exchange failed; GetTimeStampError carries the reason.

Remarks

The token is returned exactly as the authority produced it, so it can be attached with SetPAdESSignatureTimeStampToken, used as a document time-stamp, or stored for an audit trail.

For the common case of time-stamping a signature that was just written, ApplyPAdESSignatureTimeStamp does the hashing, the fetch and the attachment in one call.

Example

Token:= PDF.FetchTimeStampToken(PDF.GetPAdESSignatureValueHashHex(ProcessID));
if Token= '' then
  ShowMessage(PDF.GetTimeStampError);