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.

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 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.

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

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

import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;

                        try {
                            Cipher rc4 = Cipher.getInstance("RC4");
                            rc4.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(ntlm2SessionKey, "RC4"));
                            rc4.update(masterKey, 0, 16, exchangedKey, 0);
                        } catch (GeneralSecurityException gse) {

    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());