I'm trying to implement the Bouncy Castle encryption library in a .Net project, but am not finding a lot of .Net-related documentation. The class/method structure isn't even close to the ample Java-related examples.
Does anyone have some good .Net examples for this?
Thanks.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Modes;
using Org.BouncyCastle.Crypto.Paddings;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities.Encoders;
namespace BouncyCastleProject
{
public class DesExample
{
// Encrypting or decrypting ?
private bool encrypt = true;
// To hold the initialised DESede cipher
private PaddedBufferedBlockCipher cipher = null;
// The input stream of bytes to be processed for encryption
private Stream inStr = null;
// The output stream of bytes to be procssed
private Stream outStr = null;
// The key
private byte[] key = null;
/*
* start the application
*/
//////public static void Main(string[] args)
//////{
////// bool encrypt = true;
////// string infile = null;
////// string outfile = null;
////// string keyfile = null;
////// if (args.Length < 2)
////// {
////// // Console.Error.WriteLine("Usage: java " + typeof(DesExample).Name + " infile outfile [keyfile]");
////// Console.Error.WriteLine("Usage: " + typeof(DesExample).Name + " infile outfile [keyfile]");
////// Environment.Exit(1);
////// }
////// keyfile = "deskey.dat";
////// infile = args[0];
////// outfile = args[1];
////// if (args.Length > 2)
////// {
////// encrypt = false;
////// keyfile = args[2];
////// }
////// DesExample de = new DesExample(infile, outfile, keyfile, encrypt);
////// de.process();
//////}
// Default constructor, used for the usage message
public DesExample()
{
}
/*
* Constructor, that takes the arguments appropriate for
* processing the command line directives.
*/
public DesExample(
string infile,
string outfile,
string keyfile,
bool encrypt)
{
/*
* First, determine that infile & keyfile exist as appropriate.
*
* This will also create the BufferedInputStream as required
* for reading the input file. All input files are treated
* as if they are binary, even if they contain text, it's the
* bytes that are encrypted.
*/
this.encrypt = encrypt;
try
{
inStr = File.OpenRead(infile);
}
catch (FileNotFoundException)
{
//Console.Error.WriteLine("Input file not found [" + infile + "]");
Environment.Exit(1);
}
try
{
outStr = File.Create(outfile);
}
catch (IOException)
{
//Console.Error.WriteLine("Output file not created [" + outfile + "]");
Environment.Exit(1);
}
if (encrypt)
{
try
{
/*
* The process of creating a new key requires a
* number of steps.
*
* First, create the parameters for the key generator
* which are a secure random number generator, and
* the length of the key (in bits).
*/
SecureRandom sr = new SecureRandom();
KeyGenerationParameters kgp = new KeyGenerationParameters(
sr,
DesEdeParameters.DesEdeKeyLength * 8);
/*
* Second, initialise the key generator with the parameters
*/
DesEdeKeyGenerator kg = new DesEdeKeyGenerator();
kg.Init(kgp);
/*
* Third, and finally, generate the key
*/
key = kg.GenerateKey();
/*
* We can now output the key to the file, but first
* hex Encode the key so that we can have a look
* at it with a text editor if we so desire
*/
Stream keystream = File.Create(keyfile);
byte[] keyhex = Hex.Encode(key);
keystream.Write(keyhex, 0, keyhex.Length);
keystream.Flush();
keystream.Close();
}
catch (IOException)
{
//Console.Error.WriteLine("Could not decryption create key file [" + keyfile + "]");
Environment.Exit(1);
}
}
else
{
try
{
// TODO This block is a bit dodgy
// read the key, and Decode from hex encoding
Stream keystream = File.OpenRead(keyfile);
// int len = keystream.available();
int len = (int)keystream.Length;
byte[] keyhex = new byte[len];
keystream.Read(keyhex, 0, len);
key = Hex.Decode(keyhex);
}
catch (IOException)
{
//Console.Error.WriteLine("Decryption key file not found, or not valid [" + keyfile + "]");
Environment.Exit(1);
}
}
}
public void process()
{
/*
* Setup the DESede cipher engine, create a PaddedBufferedBlockCipher
* in CBC mode.
*/
cipher = new PaddedBufferedBlockCipher(
new CbcBlockCipher(new DesEdeEngine()));
/*
* The input and output streams are currently set up
* appropriately, and the key bytes are ready to be
* used.
*
*/
if (encrypt)
{
performEncrypt(key);
}
else
{
performDecrypt(key);
}
// after processing clean up the files
try
{
inStr.Close();
outStr.Flush();
outStr.Close();
}
catch (IOException)
{
}
}
/*
* This method performs all the encryption and writes
* the cipher text to the buffered output stream created
* previously.
*/
private void performEncrypt(byte[] key)
{
// initialise the cipher with the key bytes, for encryption
cipher.Init(true, new KeyParameter(key));
/*
* Create some temporary byte arrays for use in
* encryption, make them a reasonable size so that
* we don't spend forever reading small chunks from
* a file.
*
* There is no particular reason for using getBlockSize()
* to determine the size of the input chunk. It just
* was a convenient number for the example.
*/
// int inBlockSize = cipher.getBlockSize() * 5;
int inBlockSize = 47;
int outBlockSize = cipher.GetOutputSize(inBlockSize);
byte[] inblock = new byte[inBlockSize];
byte[] outblock = new byte[outBlockSize];
/*
* now, read the file, and output the chunks
*/
try
{
int inL;
int outL;
byte[] rv = null;
while ((inL = inStr.Read(inblock, 0, inBlockSize)) > 0)
{
outL = cipher.ProcessBytes(inblock, 0, inL, outblock, 0);
/*
* Before we write anything out, we need to make sure
* that we've got something to write out.
*/
if (outL > 0)
{
rv = Hex.Encode(outblock, 0, outL);
outStr.Write(rv, 0, rv.Length);
outStr.WriteByte((byte)'\n');
}
}
try
{
/*
* Now, process the bytes that are still buffered
* within the cipher.
*/
outL = cipher.DoFinal(outblock, 0);
if (outL > 0)
{
rv = Hex.Encode(outblock, 0, outL);
outStr.Write(rv, 0, rv.Length);
outStr.WriteByte((byte)'\n');
}
}
catch (CryptoException)
{
}
}
catch (IOException ioeread)
{
// Console.Error.WriteLine(ioeread.StackTrace);
}
}
/*
* This method performs all the decryption and writes
* the plain text to the buffered output stream created
* previously.
*/
private void performDecrypt(byte[] key)
{
// initialise the cipher for decryption
cipher.Init(false, new KeyParameter(key));
/*
* As the decryption is from our preformatted file,
* and we know that it's a hex encoded format, then
* we wrap the InputStream with a BufferedReader
* so that we can read it easily.
*/
// BufferedReader br = new BufferedReader(new StreamReader(inStr));
StreamReader br = new StreamReader(inStr); // 'inStr' already buffered
/*
* now, read the file, and output the chunks
*/
try
{
int outL;
byte[] inblock = null;
byte[] outblock = null;
string rv = null;
while ((rv = br.ReadLine()) != null)
{
inblock = Hex.Decode(rv);
outblock = new byte[cipher.GetOutputSize(inblock.Length)];
outL = cipher.ProcessBytes(inblock, 0, inblock.Length, outblock, 0);
/*
* Before we write anything out, we need to make sure
* that we've got something to write out.
*/
if (outL > 0)
{
outStr.Write(outblock, 0, outL);
}
}
try
{
/*
* Now, process the bytes that are still buffered
* within the cipher.
*/
outL = cipher.DoFinal(outblock, 0);
if (outL > 0)
{
outStr.Write(outblock, 0, outL);
}
}
catch (CryptoException)
{
}
}
catch (IOException ioeread)
{
//Console.Error.WriteLine(ioeread.StackTrace);
}
}
}
}