hr.tstrelar.pdfsigcheck.helpers.DocumentRevision.java Source code

Introduction

Here is the source code for hr.tstrelar.pdfsigcheck.helpers.DocumentRevision.java

Source

/* This program is free software. It comes without any warranty, to
 * the extent permitted by applicable law. You can redistribute it
 * and/or modify it under the terms of the Do What The Fuck You Want
 * To Public License, Version 2, as published by Sam Hocevar. See
 * http://sam.zoy.org/wtfpl/COPYING for more details. */

package hr.tstrelar.pdfsigcheck.helpers;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.KeyStore;
import java.security.SignatureException;
import java.security.cert.Certificate;
import java.security.cert.CertificateEncodingException;
import java.security.cert.X509Certificate;
import java.util.Calendar;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.itextpdf.text.pdf.AcroFields;
import com.itextpdf.text.pdf.PdfPKCS7;
import com.itextpdf.text.pdf.PdfPKCS7.X509Name;

public class DocumentRevision {
    private AcroFields af;
    private String signatureName;
    private PdfPKCS7 pk;
    private KeyStore kall;
    private Logger logger = Logger.getLogger(this.getClass().getCanonicalName());
    private static int revisionNo;

    protected DocumentRevision(AcroFields af, KeyStore kall, String signatureName) {
        this.af = af;
        this.kall = kall;
        this.signatureName = signatureName;
        pk = af.verifySignature(signatureName);

    }

    public void extract() {
        try {
            FileOutputStream out = null;
            InputStream ip = null;
            try {
                out = new FileOutputStream("revision_" + signatureName + ".pdf");
                byte bb[] = new byte[8192];
                ip = af.extractRevision(signatureName);
                int n = 0;
                while ((n = ip.read(bb)) > 0)
                    out.write(bb, 0, n);

            } finally {
                if (out != null)
                    out.close();
                if (ip != null)
                    ip.close();
            }
        } catch (IOException ioex) {
            logIt(Level.SEVERE, ioex.getLocalizedMessage());
        }
    }

    public X509Name getSubject() {
        return PdfPKCS7.getSubjectFields(pk.getSigningCertificate());
    }

    public boolean isDocumentModified() throws SignatureException {
        boolean verify = pk.verify();
        Level level = verify ? Level.INFO : Level.WARNING;
        logIt(level, "Verify OK: " + verify);
        return !verify;
    }

    public Object verify(String certFile) throws FileNotFoundException {
        logIt(Level.INFO, ((X509Certificate) pk.getSigningCertificate()).toString());

        Calendar cal = pk.getSignDate();
        Certificate pkc[] = pk.getCertificates();

        Object fails[] = PdfPKCS7.verifyCertificates(pkc, kall, null, cal);

        Object retValue = null;
        if (fails == null) {
            logIt(Level.INFO, "Certificates verified against the KeyStore");
        } else {
            logIt(Level.WARNING, "Certificate failed: " + fails[1]);
            retValue = fails[1];
        }

        if (certFile != null) {
            writeFiles(certFile);
        }
        revisionNo++;

        return retValue;
    }

    public Object verify() { //ne treba FileNotFoundException jer nema fajla
        Object retValue = null;
        try {
            retValue = verify(null);
        } catch (FileNotFoundException e) {
            assert (false); //nemogue da ovdje bude exception
        }
        return retValue;

    }

    private void writeFiles(String certFile) {
        Certificate[] certChain = pk.getSignCertificateChain();
        int i = 0;
        String certFileName;
        String certFileExt = "";
        if (certFile.contains(".")) {
            int columnIdx = certFile.indexOf('.');
            certFileName = certFile.substring(0, columnIdx);
            certFileExt = certFile.substring(columnIdx);
        } else {
            certFileName = certFile;
        }
        try {
            for (Certificate cert : certChain) {
                System.out.println(cert.toString());
                if (i == 0) {
                    doWrite(new File(certFileName + "_rev" + revisionNo + certFileExt), cert.getEncoded());
                } else {
                    doWrite(new File(certFileName + i + "_rev" + revisionNo + certFileExt), cert.getEncoded());

                }
                i++;
            }
        } catch (IOException ioex) {
            logIt(Level.SEVERE, ioex.getLocalizedMessage());
        } catch (CertificateEncodingException ceex) {
            logIt(Level.SEVERE, ceex.getLocalizedMessage());
        }
    }

    private void doWrite(File file, byte[] data) throws IOException {
        FileOutputStream fos = null;
        BufferedOutputStream out = null;

        try {
            fos = new FileOutputStream(file);
            out = new BufferedOutputStream(fos);
            out.write(data);
        } finally {
            out.flush();
            out.close();
            fos.close();
        }

    }

    public String getSignatureName() {
        return signatureName;
    }

    public boolean signatureCoversWholeDocument() {
        boolean covers = af.signatureCoversWholeDocument(signatureName);
        logIt(Level.INFO, "Signature covers whole document: " + covers);
        return covers;
    }

    public int getRevisionNumber() {
        int revNum = af.getRevision(signatureName);
        logIt(Level.INFO, "Revision number " + revNum);
        return revNum;
    }

    private void logIt(Level level, String msg) {
        logger.log(level, signatureName + ": " + msg);
    }

}