com.itextpdf.signatures.ITSAClient Maven / Gradle / Ivy
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2024 Apryse Group NV
Authors: Apryse Software.
This program is offered under a commercial and under the AGPL license.
For commercial licensing, contact us at https://itextpdf.com/sales. For AGPL licensing, see below.
AGPL licensing:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
*/
package com.itextpdf.signatures;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
/**
* Time Stamp Authority client (caller) interface.
*
* Interface used by the PdfPKCS7 digital signature builder to call
* Time Stamp Authority providing RFC 3161 compliant time stamp token.
*/
public interface ITSAClient {
/**
* Get the time stamp estimated token size.
* Implementation must return value large enough to accommodate the
* entire token returned by {@link #getTimeStampToken(byte[])} prior
* to actual {@link #getTimeStampToken(byte[])} call.
*
* @return an estimate of the token size
*/
int getTokenSizeEstimate();
/**
* Returns the {@link MessageDigest} to digest the data imprint
*
* @return The {@link MessageDigest} object.
* @throws GeneralSecurityException the general security exception
*/
MessageDigest getMessageDigest() throws GeneralSecurityException;
/**
* Returns RFC 3161 timeStampToken.
*
* @param imprint byte[] - data imprint to be time-stamped
* @return byte[] - encoded, TSA signed data of the timeStampToken
* @throws Exception - TSA request failed
*/
byte[] getTimeStampToken(byte[] imprint) throws Exception;
}