/*
* $Id: LtvTimestamp.java 5400 2012-09-12 10:12:17Z blowagie $
*
* This file is part of the iText (R) project.
* Copyright (c) 1998-2012 1T3XT BVBA
* Authors: Bruno Lowagie, Paulo Soares, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
* 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
*
* 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 http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: sales@itextpdf.com
*/
package com.itextpdf.text.pdf.security;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Rectangle;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfSignature;
import com.itextpdf.text.pdf.PdfSignatureAppearance;
import com.itextpdf.text.pdf.PdfString;
import java.io.IOException;
import java.io.InputStream;
import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.util.HashMap;
/**
* PAdES-LTV Timestamp
* @author Paulo Soares
*/
public class LtvTimestamp {
/**
* Signs a document with a PAdES-LTV Timestamp. The document is closed at the end.
* @param sap the signature appearance
* @param tsa the timestamp generator
* @param signatureName the signature name or null to have a name generated
* automatically
* @throws DocumentException
* @throws IOException
* @throws GeneralSecurityException
*/
public static void timestamp(PdfSignatureAppearance sap, TSAClient tsa, String signatureName) throws IOException, DocumentException, GeneralSecurityException {
int contentEstimated = tsa.getTokenSizeEstimate();
sap.setVisibleSignature(new Rectangle(0,0,0,0), 1, signatureName);
PdfSignature dic = new PdfSignature(PdfName.ADOBE_PPKLITE, PdfName.ETSI_RFC3161);
dic.put(PdfName.TYPE, PdfName.DOCTIMESTAMP);
sap.setCryptoDictionary(dic);
HashMap<PdfName,Integer> exc = new HashMap<PdfName,Integer>();
exc.put(PdfName.CONTENTS, new Integer(contentEstimated * 2 + 2));
sap.preClose(exc);
InputStream data = sap.getRangeStream();
MessageDigest messageDigest = tsa.getMessageDigest();
byte[] buf = new byte[4096];
int n;
while ((n = data.read(buf)) > 0) {
messageDigest.update(buf, 0, n);
}
byte[] tsImprint = messageDigest.digest();
byte[] tsToken;
try {
tsToken = tsa.getTimeStampToken(tsImprint);
}
catch(Exception e) {
throw new GeneralSecurityException(e);
}
if (contentEstimated + 2 < tsToken.length)
throw new IOException("Not enough space");
byte[] paddedSig = new byte[contentEstimated];
System.arraycopy(tsToken, 0, paddedSig, 0, tsToken.length);
PdfDictionary dic2 = new PdfDictionary();
dic2.put(PdfName.CONTENTS, new PdfString(paddedSig).setHexWriting(true));
sap.close(dic2);
}
}