javax.crypto.Cipher - The Secret Key Encryption Class

This section provides a quick introduction of the cipher class, javax.crypto.Cipher, to encrypt input data with a secret key.

In the previous chapter, I learned how to use classes and interfaces in the JCE (Java Cryptography Extension) package to generate and manage secret keys. Now I am ready to learn how to use secret keys to encrypt or cipher any input data using the javax.crypto.Cipher class.

javax.crypto.Cipher is a class that provides functionality of a cryptographic cipher for encryption and decryption. It has the following major methods.

getInstance() - Returns a Cipher object of the specified transformation (algorithm plus options) from the implementation of the specified provider. If provider is not specified, the default implementation is used. This is a static method.

init() - Initializes this cipher for the specified operation mode with the specified key or public key certificate. Two important operation modes are Cipher.ENCRYPT_MODE and Cipher.DECRYPT_MODE.

update() - Feeds additional input data to this cipher and generates partial output data.

doFinal() - Feeds the last part of the input data to this cipher and generates the last part of the output data.

getBlockSize() - Returns the block size of this cipher.

getAlgorithm() - Returns the algorithm name of this cipher.

getProvider() - Returns the provider as a Provider object of this cipher.

See the next section how to use the javax.crypto.Cipher class in a sample program.

Table of Contents

 About This Book

 Cryptography Terminology

 Cryptography Basic Concepts

 Introduction to AES (Advanced Encryption Standard)

 Introduction to DES Algorithm

 DES Algorithm - Illustrated with Java Programs

 DES Algorithm Java Implementation

 DES Algorithm - Java Implementation in JDK JCE

 DES Encryption Operation Modes

 DES in Stream Cipher Modes

 PHP Implementation of DES - mcrypt

 Blowfish - 8-Byte Block Cipher

 Secret Key Generation and Management

Cipher - Secret Key Encryption and Decryption

javax.crypto.Cipher - The Secret Key Encryption Class - Secret Key Encryption Sample Program

 Blowfish Secret Key Encryption Tests

 Introduction of RSA Algorithm

 RSA Implementation using java.math.BigInteger Class

 Introduction of DSA (Digital Signature Algorithm)

 Java Default Implementation of DSA

 Private key and Public Key Pair Generation

 PKCS#8/X.509 Private/Public Encoding Standards

 Cipher - Public Key Encryption and Decryption

 MD5 Mesasge Digest Algorithm

 SHA1 Mesasge Digest Algorithm

 OpenSSL Introduction and Installation

 OpenSSL Generating and Managing RSA Keys

 OpenSSL Managing Certificates

 OpenSSL Generating and Signing CSR

 OpenSSL Validating Certificate Path

 "keytool" and "keystore" from JDK

 "OpenSSL" Signing CSR Generated by "keytool"

 Migrating Keys from "keystore" to "OpenSSL" Key Files

 Certificate X.509 Standard and DER/PEM Formats

 Migrating Keys from "OpenSSL" Key Files to "keystore"

 Using Certificates in IE

 Using Certificates in Google Chrome

 Using Certificates in Firefox

 Archived Tutorials


 Full Version in PDF/EPUB