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The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8 with debug enabled.

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package org.bouncycastle.crypto.generators;

import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.PBEParametersGenerator;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.crypto.params.ParametersWithIV;
import org.bouncycastle.crypto.util.DigestFactory;

/**
 * Generator for PBE derived keys and ivs as usd by OpenSSL.
 * 

* The scheme is a simple extension of PKCS 5 V2.0 Scheme 1 using MD5 with an * iteration count of 1. *

*/ public class OpenSSLPBEParametersGenerator extends PBEParametersGenerator { private Digest digest = DigestFactory.createMD5(); /** * Construct a OpenSSL Parameters generator. */ public OpenSSLPBEParametersGenerator() { } /** * Initialise - note the iteration count for this algorithm is fixed at 1. * * @param password password to use. * @param salt salt to use. */ public void init( byte[] password, byte[] salt) { super.init(password, salt, 1); } /** * the derived key function, the ith hash of the password and the salt. */ private byte[] generateDerivedKey( int bytesNeeded) { byte[] buf = new byte[digest.getDigestSize()]; byte[] key = new byte[bytesNeeded]; int offset = 0; for (;;) { digest.update(password, 0, password.length); digest.update(salt, 0, salt.length); digest.doFinal(buf, 0); int len = (bytesNeeded > buf.length) ? buf.length : bytesNeeded; System.arraycopy(buf, 0, key, offset, len); offset += len; // check if we need any more bytesNeeded -= len; if (bytesNeeded == 0) { break; } // do another round digest.reset(); digest.update(buf, 0, buf.length); } return key; } /** * Generate a key parameter derived from the password, salt, and iteration * count we are currently initialised with. * * @param keySize the size of the key we want (in bits) * @return a KeyParameter object. * @exception IllegalArgumentException if the key length larger than the base hash size. */ public CipherParameters generateDerivedParameters( int keySize) { keySize = keySize / 8; byte[] dKey = generateDerivedKey(keySize); return new KeyParameter(dKey, 0, keySize); } /** * Generate a key with initialisation vector parameter derived from * the password, salt, and iteration count we are currently initialised * with. * * @param keySize the size of the key we want (in bits) * @param ivSize the size of the iv we want (in bits) * @return a ParametersWithIV object. * @exception IllegalArgumentException if keySize + ivSize is larger than the base hash size. */ public CipherParameters generateDerivedParameters( int keySize, int ivSize) { keySize = keySize / 8; ivSize = ivSize / 8; byte[] dKey = generateDerivedKey(keySize + ivSize); return new ParametersWithIV(new KeyParameter(dKey, 0, keySize), dKey, keySize, ivSize); } /** * Generate a key parameter for use with a MAC derived from the password, * salt, and iteration count we are currently initialised with. * * @param keySize the size of the key we want (in bits) * @return a KeyParameter object. * @exception IllegalArgumentException if the key length larger than the base hash size. */ public CipherParameters generateDerivedMacParameters( int keySize) { return generateDerivedParameters(keySize); } }





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