我正在创建一个客户机/服务器程序来执行256位aes加密。我从ecdh那里得到我的钥匙。我发送用于表示各种键和字符串的字节数组的大小。我遇到的问题是，当我试图将加密字符串的大小从客户端发送到服务器时，服务器会说我发送的大小比实际发送的要大得多。发送大小适用于所有其他需要发送的字节数组。从客户端发送的加密字符串的大小为16字节。服务器接收的整数大小为276032497字节。我已经检查，我实际上是从客户端发送16字节。
你知道问题是什么吗？


服务器代码：

//generate public key for server
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("EC");
        kpg.initialize(256);
        KeyPair kp = kpg.generateKeyPair();
        byte[] ourPk = kp.getPublic().getEncoded();
        String format = kp.getPublic().getFormat();
        int ourPkLength = ourPk.length;

        int arrSize;

        //send client our pk 
        out.writeInt(ourPkLength);
        out.write(ourPk);
        System.out.println("sent PK!");

        //receive pk from client
        arrSize = fromClient.readInt();
        byte[] otherPk = new byte[arrSize];
        fromClient.read(otherPk);
        System.out.println("recived client PK!");

        KeyFactory kf = KeyFactory.getInstance("EC");
        X509EncodedKeySpec pkSpec = new X509EncodedKeySpec(otherPk);
        PublicKey otherPublicKey = kf.generatePublic(pkSpec);

        //Perform key agreement 
        KeyAgreement ka = KeyAgreement.getInstance("ECDH");
        ka.init(kp.getPrivate());
        ka.doPhase(otherPublicKey, true);

        // Send shared secret
        byte[] sharedSecret = ka.generateSecret();

        // Derive a key from the shared secret and both public keys
        MessageDigest hash = MessageDigest.getInstance("SHA-256");
        hash.update(sharedSecret);
        // Simple deterministic ordering
        List<ByteBuffer> keys = Arrays.asList(ByteBuffer.wrap(ourPk), ByteBuffer.wrap(otherPk));
        Collections.sort(keys);
        hash.update(keys.get(0));
        hash.update(keys.get(1));

        byte[] derivedKey = hash.digest();

        System.out.println("derived key: " + derivedKey + "  length: " + derivedKey.length);

        //Convert byte [] to secret key
        //Define cipher
        SecretKeySpec symmetricKey = new SecretKeySpec(derivedKey, 0, 32, "AES");
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, symmetricKey, new IvParameterSpec(new byte[16]));

        //receive encrypted message from client and try to decrypt. 
        arrSize = fromClient.readInt();
        System.out.println("array size sent: " + arrSize);
        byte[] decryptArr = new byte[arrSize];
        fromClient.read(decryptArr);
        System.out.println("Recieved encrypted string: " + decryptArr + "    length:   " + decryptArr.length);
        String decryptStr = Base64.getEncoder().encodeToString(cipher.doFinal(decryptArr));

        System.out.println("Decrypted String: " + decryptStr);

客户代码：

//generate public key for client
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("EC");
        kpg.initialize(256);
        KeyPair kp = kpg.generateKeyPair();
        byte[] ourPk = kp.getPublic().getEncoded();
        //String format = kp.getPublic().getFormat();
        int ourPkLength = ourPk.length;

    int arrSize;

    //Receive generated public key from the Server
    arrSize = fromServ.readInt();
    byte[] otherPk = new byte[arrSize];
    fromServ.read(otherPk);
    System.out.println("recived server PK!");

    //Send the server our public key 
    out.writeInt(ourPkLength);
    out.write(ourPk);
    System.out.println("sent PK!");

    KeyFactory kf = KeyFactory.getInstance("EC");
    X509EncodedKeySpec pkSpec = new X509EncodedKeySpec(otherPk);
    PublicKey otherPublicKey = kf.generatePublic(pkSpec);

    //Perform key agreement 
    KeyAgreement ka = KeyAgreement.getInstance("ECDH");
    ka.init(kp.getPrivate());
    ka.doPhase(otherPublicKey, true);

    // Generate a shared secret
    byte[] sharedSecret = ka.generateSecret();

    // Derive a key from the shared secret and both public keys
    MessageDigest hash = MessageDigest.getInstance("SHA-256");
    hash.update(sharedSecret);
    // Simple deterministic ordering
    List<ByteBuffer> keys = Arrays.asList(ByteBuffer.wrap(ourPk), ByteBuffer.wrap(otherPk));
    Collections.sort(keys);
    hash.update(keys.get(0));
    hash.update(keys.get(1));

    byte[] derivedKey = hash.digest();   
    System.out.println("derived key: " + derivedKey + "  length: " + derivedKey.length);

    //Convert the derivedkey from a byte array to a Secret key Spec of type AES
    SecretKeySpec secretKey = new SecretKeySpec(derivedKey, 0, 32, "AES");
    Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    cipher.init(Cipher.ENCRYPT_MODE, secretKey, new IvParameterSpec(new byte[16]));
    String plainText = "Testing!";
    byte[] cipherText = cipher.doFinal(plainText.getBytes());
    System.out.println("Encrypted str: " + cipherText + "    length: "+ cipherText.length);

    //Send encrypted string to Server
    int len = cipherText.length;
    System.out.println("length: " + len);
    out.write(len);
    out.write(cipherText);
    System.out.println("Sent encrypted string!");