/**
     * Encrypts an 8-byte block using DES
     * @param clearText the 8-byte plaintext block
     * @param cipherText the output 8-byte ciphertext block
     */
    public void encrypt(final byte[] clearText, final byte[] cipherText) {
        encrypt(clearText, 0, cipherText, 0);
    }

    /// Decrypt a block of bytes.
    /**
     * Decrypts an 8-byte block using DES

    /**
     * The queue of ciphers for decryption.
     */
    protected Queue<Cipher> decryptoQueue = new ConcurrentLinkedQueue<>();

    /**
     * Encrypts the given data.
     *
     * @param data
     *            the data to encrypt
     * @return the encrypted data
     */
    public byte[] encrypto(final byte[] data) {

            j = j + key[ki + i % klen] + s[i] & 0xff;
            final byte t = s[i];
            s[i] = s[j];
            s[j] = t;
        }

        i = j = 0;
    }

    /**
     * Encrypts or decrypts data using the RC4 stream cipher.
     * Since RC4 is a stream cipher, the same operation is used for both encryption and decryption.
     *
     * @param src the source data array

	if strings.HasPrefix(kmsID, ARNPrefix) {
		return kmsID
	}
	return ARNPrefix + kmsID
}

// DecryptETags decryptes the ETag of all ObjectInfos using the KMS.
//
// It adjusts the size of all encrypted objects since encrypted
// objects are slightly larger due to encryption overhead.
// Further, it decrypts all single-part SSE-S3 encrypted objects
// and formats ETags of SSE-C / SSE-KMS encrypted objects to
// be AWS S3 compliant.

## Server-Side Encryption

MinIO supports two different types of server-side encryption ([SSE](#sse)):

- **SSE-C**: The MinIO server en/decrypts an object with a secret key provided by the S3 client as part of the HTTP request headers. Therefore, [SSE-C](#ssec) requires TLS/HTTPS.
- **SSE-S3**: The MinIO server en/decrypts an object with a secret key managed by a KMS. Therefore, MinIO requires a valid KMS configuration for [SSE-S3](#sses3).

# KMS Guide [![Slack](https://slack.min.io/slack?type=svg)](https://slack.min.io)

MinIO uses a key-management-system (KMS) to support SSE-S3. If a client requests SSE-S3, or auto-encryption is enabled, the MinIO server encrypts each object with a unique object key which is protected by a master key managed by the KMS.

## Quick Start

	}
	files.OptimizeSize()
	zipInfo, err := files.Serialize()
	if err != nil {
		return nil, err
	}
	at := archiveType
	zipInfoStr := string(zipInfo)
	if opts.EncryptFn != nil {
		at = archiveTypeEnc
		zipInfoStr = string(opts.EncryptFn(archiveTypeEnc, zipInfo))
	}
	srcInfo.UserDefined[archiveTypeMetadataKey] = at
	popts := ObjectOptions{
		MTime:     srcInfo.ModTime,
		VersionID: srcInfo.VersionID,

## FAQ

> Why is this change needed?

Before, there were two separate mechanisms - S3 objects got encrypted using a KMS,
if present, and the IAM / configuration data got encrypted with the root credentials.
Now, MinIO encrypts IAM / configuration and S3 objects with a KMS, if present. This
change unified the key-management aspect within MinIO.

The unified KMS-based approach has several advantages:

		return opts, err
	}
	opts.MTime = mtime
	opts.UserDefined = make(map[string]string)
	// Transfer SSEC key in opts.EncryptFn
	if crypto.SSEC.IsRequested(r.Header) {
		key, err := ParseSSECustomerRequest(r)
		if err == nil {
			// Set EncryptFn to return SSEC key
			opts.EncryptFn = func(baseKey string, data []byte) []byte {
				return key
			}
		}
	}

	kind, _ := crypto.IsEncrypted(fi.Metadata)

	var objectEncryptionKey []byte
	switch kind {
	case crypto.SSEC:
		if checksumType.IsSet() {
			if opts.EncryptFn == nil {
				return oi, crypto.ErrMissingCustomerKey
			}
			baseKey := opts.EncryptFn("", nil)
			if len(baseKey) != 32 {
				return oi, crypto.ErrInvalidCustomerKey
			}