com.fasteasytrade.JRandTest.Algo
Class RSACrypt

java.lang.Object
  com.fasteasytrade.JRandTest.Algo.Cipher
      com.fasteasytrade.JRandTest.Algo.RSACrypt

public class RSACrypt

extends Cipher

Java RSA algorithm implementation.

 2 Sep 2003: Zur Aougav
 2 Sep 2003: Copyright (c) 2003 Zur Aougav 
 2 Sep 2003: New RSA java class.
 2 Sep 2003: Use simple securerandom class to generate p & q primes.
 2 Sep 2003: Read and write biginteger to/from streams as object or simple outputstream (with length).
 2 Sep 2003: Vector encrypt(byte[] message) does not handle the last bytes properly. Buffer
		is filled with 0. Decryption will have 0 (nulls) at end of decoded string.
 3 Sep 2003: Add test in main: Shall I compare thee to a summer's day. Shakespeare.
 3 Sep 2003: Add save/loadPublicKey and save/loadPrivateKey.
 3 Sep 2003: Add -g option: to generate and print keys.
 3 Sep 2003: Add -gs option: to generate and save keys in rsapublic.key and rsaprivate.key.
 3 Sep 2003: Add encryptFile(infilename,outfilename) and decryptFile(infilename,outfilename).
 4 Sep 2003: Add GZIP support.
		encryptFileGzip(infilename,outfilename) and decryptFileGzip(infilename,outfilename).
 4 Sep 2003: Changed default e=3 to e=65537.
 17  Mar 2005: encrypt (0 || random 32 bits || data).
 

Author:

Zur Aougav

Field Summary

(package private) BigInteger	d
(package private) BigInteger	e
(package private) int	msglen
(package private) BigInteger	n
(package private) Random	rnd

Constructor Summary

RSACrypt()
Almost null contructor

Method Summary

BigInteger	decrypt(BigInteger message) Decrypt one big integer
void	decryptFile(String infile, String outfile) decrypt infile to outfile.
void	decryptFileGzip(String infile, String outfile)
BigInteger	encrypt(BigInteger message) Encrypt one big integer
Vector	encrypt(byte[] message) encrypt byte[] and returns vector of bigintegers.
Vector	encrypt(byte[] message, int mlen) encrypt byte[] and returns vector of bigintegers.
void	encryptFile(String infile, String outfile) encrypt infile to outfile.
void	encryptFileGzip(String infile, String outfile) encrypt infile to outfile with compression.
void	generateKeys(int bitlen) Generate public and private keys based on two primes, p and q, we make public (n, e), and private (n, d).
int	getMessageLength() Returns message length in bytes.
void	loadPrivateKey(String infilename) Load private key from file
void	loadPublicKey(String infilename) Load public key from file
static void	main(String[] args) Main to test several options of class
static BigInteger	read(DataInputStream in) Read one big integer from inputstream.
static BigInteger	read(ObjectInputStream in) Read one big integer from inputstream, as java object.
static BigInteger	readBigInteger(GZIPInputStream in) Read one big integer from GZIPinputstream.
static int	readInt(GZIPInputStream in) Read int from GZIPinputstream.
void	savePrivateKey(String outfilename) Save private key to file
void	savePublicKey(String outfilename) Save public key to file
static void	test1() Just testing RSA class
static void	usage() Print usage of main RSA class
static void	write(BigInteger v, DataOutputStream out) Write one big integer to outputstream, including length.
static void	write(BigInteger v, GZIPOutputStream out) Write one big integer to GZIPoutputstream, including length.
static void	write(BigInteger v, ObjectOutputStream out) Write one big integer to outputstream, as java object.
static void	write(int v, GZIPOutputStream out) Write int to GZIPOutputStream

Methods inherited from class com.fasteasytrade.JRandTest.Algo.Cipher

compareBytes

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

n

BigInteger n

d

BigInteger d

e

BigInteger e

msglen

int msglen

rnd

Random rnd

Constructor Detail

RSACrypt

public RSACrypt()

Almost null contructor

Method Detail

generateKeys

public void generateKeys(int bitlen)

Generate public and private keys based on two primes, p and q, we make public (n, e), and private (n, d). We discard p and q.

encrypt

public BigInteger encrypt(BigInteger message)

Encrypt one big integer

decrypt

public BigInteger decrypt(BigInteger message)

Decrypt one big integer

encrypt

public Vector encrypt(byte[] message)

encrypt byte[] and returns vector of bigintegers.

encrypt

public Vector encrypt(byte[] message,
                      int mlen)

encrypt byte[] and returns vector of bigintegers. encrypt just the first mlen bytes. Encrypt: byte 0 : 0 byte 1 - 4 = random number byte 5 .. getMessageLen-1 = data

encryptFile

public void encryptFile(String infile,
                        String outfile)
                 throws IOException

encrypt infile to outfile.

Throws:

IOException

decryptFile

public void decryptFile(String infile,
                        String outfile)
                 throws IOException

decrypt infile to outfile.

Throws:

IOException

encryptFileGzip

public void encryptFileGzip(String infile,
                            String outfile)
                     throws IOException

encrypt infile to outfile with compression.

Throws:

IOException

decryptFileGzip

public void decryptFileGzip(String infile,
                            String outfile)
                     throws IOException

Throws:

IOException

getMessageLength

public int getMessageLength()

Returns message length in bytes. Based on n.

write

public static void write(BigInteger v,
                         DataOutputStream out)
                  throws IOException

Write one big integer to outputstream, including length.

Throws:

IOException

write

public static void write(BigInteger v,
                         ObjectOutputStream out)
                  throws IOException

Write one big integer to outputstream, as java object.

Throws:

IOException

write

public static void write(int v,
                         GZIPOutputStream out)
                  throws IOException

Write int to GZIPOutputStream

Throws:

IOException

write

public static void write(BigInteger v,
                         GZIPOutputStream out)
                  throws IOException

Write one big integer to GZIPoutputstream, including length.

Throws:

IOException

read

public static BigInteger read(DataInputStream in)
                       throws IOException

Read one big integer from inputstream. First read length, second read bytes to build the new big integer.

Throws:

IOException

read

public static BigInteger read(ObjectInputStream in)
                       throws IOException,
                              ClassNotFoundException

Read one big integer from inputstream, as java object.

Throws:

IOException

ClassNotFoundException

readInt

public static int readInt(GZIPInputStream in)
                   throws IOException

Read int from GZIPinputstream.

Throws:

IOException

readBigInteger

public static BigInteger readBigInteger(GZIPInputStream in)
                                 throws IOException

Read one big integer from GZIPinputstream. First read length, second read bytes to build the new big integer.

Throws:

IOException

savePublicKey

public void savePublicKey(String outfilename)
                   throws IOException

Save public key to file

Throws:

IOException

loadPublicKey

public void loadPublicKey(String infilename)
                   throws IOException,
                          ClassNotFoundException

Load public key from file

Throws:

IOException

ClassNotFoundException

savePrivateKey

public void savePrivateKey(String outfilename)
                    throws IOException

Save private key to file

Throws:

IOException

loadPrivateKey

public void loadPrivateKey(String infilename)
                    throws IOException,
                           ClassNotFoundException

Load private key from file

Throws:

IOException

ClassNotFoundException

test1

public static void test1()

Just testing RSA class

usage

public static void usage()

Print usage of main RSA class

main

public static void main(String[] args)

Main to test several options of class