[Cryptix-users] Problem decrypt large file

[Stefania V. <ste...@en...>]

=20
Hello,

 I have written a java class using the cryptix libraries for the =
signature/encryption and decryption/verification of files.

 I used these classes for the streams and everything worked properly as =
long as the files were not to large. =20

 However, when I tried to decrypt a 400MB file it took about 30 minutes.

 I used the example of the "StreamDecryptVerify" libraries to implement =
my class but I would like to know if something is out of place or if it =
is possible to improve the efficiency of the class.

My code:

      java.security.Security.addProvider( new =
cryptix.jce.provider.CryptixCrypto() );
        java.security.Security.addProvider( new =
cryptix.openpgp.provider.CryptixOpenPGP() );

        =
//**********************************************************************
        // First read the keys.
        =
//**********************************************************************
        try {
            FileInputStream in; Collection msgs; KeyBundleMessage kbm;

            MessageFactory mf =3D MessageFactory.getInstance("OpenPGP");

            in =3D new FileInputStream("privatekey.pgp");
            msgs =3D mf.generateMessages(in);
            kbm =3D (KeyBundleMessage)msgs.iterator().next();
            secretBob =3D (PGPKeyBundle)kbm.getKeyBundle();
            in.close();

            in =3D new FileInputStream("pubkey.pgp");
            msgs =3D mf.generateMessages(in);
            kbm =3D (KeyBundleMessage)msgs.iterator().next();
            publicAlice =3D (PGPKeyBundle)kbm.getKeyBundle();
            in.close();
        } catch (IOException ioe) {
            System.err.println("IOException... You did remember to run =
the "+
                "GenerateAndWriteKey example first, right?");
            ioe.printStackTrace();
            System.exit(-1);
        } catch (NoSuchAlgorithmException nsae) {
            System.err.println("Cannot find the OpenPGP MessageFactory. =
"+
                "This usually means that the Cryptix OpenPGP provider is =
not "+
                "installed correctly.");
            nsae.printStackTrace();
            System.exit(-1);
        } catch (MessageException me) {
            System.err.println("Reading keybundle failed.");
            me.printStackTrace();
            System.exit(-1);
        }


        =
//**********************************************************************
        //  The actual stream decryption and verification.
        =
//**********************************************************************
        try {
            FileInputStream fileInputStream =3D
                new FileInputStream(fileToDecrypt);
            FileOutputStream fileOutputStream =3D
                new FileOutputStream(fileDecrypted);
            DecodedMessageInputStream decodedInputStream =3D
                DecodedMessageInputStream.getInstance("OpenPGP");


            decodedInputStream.init(fileInputStream, this, this);

            System.out.println("Decoding message...");


            long inizio =3D System.currentTimeMillis();
            System.out.println("inizio=3D"+inizio);

            byte[] buf =3D new byte[4096];

            int len =3D decodedInputStream.read(buf);
            while (len > 0) {
                fileOutputStream.write(buf, 0, len);
                len =3D decodedInputStream.read(buf);
            }
           =20
            long fine =3D System.currentTimeMillis();
            System.out.println("fine=3D"+fine);
            System.out.println("Tempo impiegato =3D =
"+(fine-inizio)+"millisecondi");
            System.out.println("Tempo impiegato =3D =
"+((fine-inizio)/1000)+" secondi --> ("+(((fine-inizio)/1000)/60)+" =
minuti)");
            decodedInputStream.close();
            fileInputStream.close();
            fileOutputStream.flush();
            fileOutputStream.close();

            System.out.println("Decoding done.");

            switch(decodedInputStream.getVerificationResult()) {
                case DecodedMessageInputStream.VERIFICATION_NOT_SIGNED:
                    System.out.println("Message was not signed.");
                    break;
                case =
DecodedMessageInputStream.VERIFICATION_GOOD_SIGNATURE:
                    System.out.println("Message has a GOOD signature.");
                    break;
                case =
DecodedMessageInputStream.VERIFICATION_BAD_SIGNATURE:
                    System.out.println("Message has a BAD signature.");
                    break;
                default:
                    System.out.println("Unknown verification result.");
                    break;
            }

            switch(decodedInputStream.getIntegrityResult()) {
                case DecodedMessageInputStream.INTEGRITY_NOT_PROTECTED:
                    System.out.println("Message was not integrity =
protected.");
                    break;
                case DecodedMessageInputStream.INTEGRITY_GOOD:
                    System.out.println("Message integrity preserved.");
                    break;
                case DecodedMessageInputStream.INTEGRITY_VIOLATED:
                    System.out.println("Message integrity VIOLATED.");
                    break;
                default:
                    System.out.println("Unknown intregrity result.");
                    break;
            }

        } catch (NoSuchAlgorithmException nsae) {
            System.err.println("Cannot find OpenPGP implementation."+
                " This usually means that the Cryptix OpenPGP provider =
is not "+
                "installed correctly.");
            nsae.printStackTrace();
            System.exit(-1);
        } catch (MessageStreamException me) {
            System.err.println("Streaming the message failed.");
            me.printStackTrace();
            System.exit(-1);
        } catch (IOException ioe) {
            System.err.println("IO error.");
            ioe.printStackTrace();
            System.exit(-1);
        }

 Thanks again,

Stefania