Package com.cedarsoftware.util

Class EncryptionUtilities

  • public class EncryptionUtilities
extends Object
    Useful encryption utilities that simplify tasks like getting an encrypted String return value (or MD5 hash String) for String or Stream input.
    Author:
    John DeRegnaucourt ([email protected])
    Copyright (c) Cedar Software LLC

    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

    • Method Detail

      • fastMD5

        public static String fastMD5​(File file)
        Super-fast MD5 calculation from entire file. Uses FileChannel and direct ByteBuffer (internal JVM memory).
        Parameters:
        file - File that from which to compute the MD5
        Returns:
        String MD5 value.

      • fastSHA1

        public static String fastSHA1​(File file)
        Super-fast SHA-1 calculation from entire file. Uses FileChannel and direct ByteBuffer (internal JVM memory).
        Parameters:
        file - File that from which to compute the SHA-1
        Returns:
        String SHA-1 value.

      • fastSHA256

        public static String fastSHA256​(File file)
        Super-fast SHA-256 calculation from entire file. Uses FileChannel and direct ByteBuffer (internal JVM memory).
        Parameters:
        file - File that from which to compute the SHA-256
        Returns:
        String SHA-256 value.

      • fastSHA512

        public static String fastSHA512​(File file)
        Super-fast SHA-512 calculation from entire file. Uses FileChannel and direct ByteBuffer (internal JVM memory).
        Parameters:
        file - File that from which to compute the SHA-512
        Returns:
        String SHA-512 value.

      • calculateMD5Hash

        public static String calculateMD5Hash​(byte[] bytes)
        Calculate an MD5 Hash String from the passed in byte[].
        Parameters:
        bytes - byte[] for which to obtain the MD5 hash.
        Returns:
        String of hex digits representing MD5 hash.

      • calculateSHA1Hash

        public static String calculateSHA1Hash​(byte[] bytes)
        Calculate an MD5 Hash String from the passed in byte[].
        Parameters:
        bytes - byte[] of bytes for which to compute the SHA1
        Returns:
        the SHA-1 as a String of HEX digits

      • calculateSHA256Hash

        public static String calculateSHA256Hash​(byte[] bytes)
        Calculate an SHA-256 Hash String from the passed in byte[].
        Parameters:
        bytes - byte[] for which to compute the SHA-2 (SHA-256)
        Returns:
        the SHA-2 as a String of HEX digits

      • getSHA256Digest

        public static MessageDigest getSHA256Digest()

      • calculateSHA512Hash

        public static String calculateSHA512Hash​(byte[] bytes)
        Calculate an SHA-512 Hash String from the passed in byte[].
        Parameters:
        bytes - byte[] for which to compute the SHA-3 (SHA-512)
        Returns:
        the SHA-3 as a String of HEX digits

      • getSHA512Digest

        public static MessageDigest getSHA512Digest()

      • createCipherBytes

        public static byte[] createCipherBytes​(String key,
                                       int bitsNeeded)

      • createAesCipher

        public static Cipher createAesCipher​(Key key,
                                     int mode)
                              throws Exception
        Creates a Cipher from the passed in key, using the passed in mode.
        Parameters:
        key - SecretKeySpec
        mode - Cipher.ENCRYPT_MODE or Cipher.DECRYPT_MODE
        Returns:
        Cipher instance created with the passed in key and mode.
        Throws:
        Exception - if the requested Cipher instance does not exist.

      • encrypt

        public static String encrypt​(String key,
                             String content)
        Get hex String of content String encrypted.
        Parameters:
        key - String value of the encryption key (passphrase)
        content - String value of the content to be encrypted using the passed in encryption key
        Returns:
        String of the encrypted content (HEX characters), using AES-128

      • encryptBytes

        public static String encryptBytes​(String key,
                                  byte[] content)

      • decrypt

        public static String decrypt​(String key,
                             String hexStr)
        Get unencrypted String from encrypted hex String
        Parameters:
        key - String encryption key that was used to encryption the passed in hexStr of characters.
        hexStr - String encrypted bytes (as a HEX string)
        Returns:
        String of original content, decrypted using the passed in encryption/decryption key against the passed in hex String.

      • decryptBytes

        public static byte[] decryptBytes​(String key,
                                  String hexStr)
        Get unencrypted byte[] from encrypted hex String
        Parameters:
        key - String encryption/decryption key
        hexStr - String of HEX bytes that were encrypted with an encryption key
        Returns:
        byte[] of original bytes (if the same key to encrypt the bytes was passed to decrypt the bytes).

      • calculateHash

        public static String calculateHash​(MessageDigest d,
                                   byte[] bytes)
        Calculate a hash String from the passed in byte[].
        Parameters:
        d - MessageDigest to update with the passed in bytes
        bytes - byte[] of bytes to hash
        Returns:
        String hash of the passed in MessageDigest, after being updated with the passed in bytes, as a HEX string.