// When
        Cipher encryptCipher = Crypto.getArcfour(key);
        encryptCipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key, "RC4"));
        byte[] encrypted = encryptCipher.doFinal(plaintext);

        Cipher decryptCipher = Crypto.getArcfour(key);
        decryptCipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key, "RC4"));
        byte[] decrypted = decryptCipher.doFinal(encrypted);

        // Then

import java.security.MessageDigest;
import java.util.Arrays;
import java.util.Map;

import javax.crypto.Cipher;
import javax.crypto.Mac;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import javax.security.auth.kerberos.KerberosKey;

/**
 * Utility class for calculating and verifying PAC (Privilege Attribute Certificate) message authentication codes.

   * SHA-1 (160 hash bits) hash function and a {@link SecretKeySpec} created from the given byte
   * array and the SHA-1 algorithm.
   *
   * @param key the key material of the secret key
   * @since 20.0
   */
  public static HashFunction hmacSha1(byte[] key) {
    return hmacSha1(new SecretKeySpec(checkNotNull(key), "HmacSHA1"));
  }

  /**

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Provider;

import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import jcifs.CIFSUnsupportedCryptoException;

/**
 * Cryptographic utility class providing encryption and decryption functionality for jCIFS.

     */
    protected Cipher pollEncryptoCipher() {
        Cipher cipher = encryptoQueue.poll();
        if (cipher == null) {
            try {
                final SecretKeySpec sksSpec = new SecretKeySpec(key.getBytes(charsetName), algorithm);
                cipher = Cipher.getInstance(algorithm);
                cipher.init(Cipher.ENCRYPT_MODE, sksSpec);
            } catch (final InvalidKeyException e) {

            }

            // Create cipher with the copy - algorithm is just "AES" for SecretKeySpec
            final SecretKeySpec keySpec = new SecretKeySpec(keyCopy, "AES");
            final Cipher cipher = Cipher.getInstance(transformation);
            final GCMParameterSpec gcmSpec = new GCMParameterSpec(getAuthTagLength() * 8, nonce);

package jcifs.internal.smb2;

import java.security.GeneralSecurityException;
import java.security.MessageDigest;
import java.util.concurrent.locks.ReentrantLock;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import jcifs.internal.CommonServerMessageBlock;
import jcifs.internal.SMBSigningDigest;
import jcifs.internal.util.SMBUtil;
import jcifs.util.Crypto;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import javax.security.auth.DestroyFailedException;
import javax.security.auth.Destroyable;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Secure credential storage with encryption at rest.

import java.security.SecureRandom;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.security.auth.DestroyFailedException;
import javax.security.auth.Destroyable;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Secure key management for SMB encryption.

    public byte[] generateChannelBindingHash(ChannelInfo channel) throws GeneralSecurityException {
        // Use HMAC-SHA256 for channel binding
        Mac mac = Mac.getInstance("HmacSHA256");
        SecretKeySpec keySpec = new SecretKeySpec(sessionKey, "HmacSHA256");
        mac.init(keySpec);
        
        // Include channel-specific data
        mac.update(channel.getLocalInterface().getAddress().getAddress());