Description

This is a utility to encrypt/decrypt using AES/CBC/PKCS5Padding algorithm

• Most common error_: "Invalid Key Size" error is most likely caused by not updating JCE strength policy, see above
• https://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters NOTE: This example is built using JDK8, ultimate strength JCE (JDK8) and Maven 3.x

Getting Started:

git clone https://github.com/quantum-fusion/aes-256-encryption-utility

cd aes-256-encryption-utility

mvn clean install

Installation

===================

- Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files 8 Download

http://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html

- JDK must have the unlimited strength policy for the JDK version

Extract the jar files from the zip and save them in ${java.home}/jre/lib/security/.

To Run

====================

mvn clean test

To Use

====================

# Key stored in JCEKS formatted Java keystore
Key key = ....; // see tests pulling key from keystore
// alternative is to hard-code key in string
AESCipher cipher = new AESCipher(key);

String encryptedMessage = cipher.getEncryptedMessage("this is message");
String decryptedMessage = cipher.getDecryptedMessage(encryptedMessage);

AESCipher cipherWithIv = new AESCipher(key, "0123456789012345".getBytes());
String encryptedMessage = cipherWithIv.getEncryptedMessage("this is message");
String decryptedMessage = cipherWithIv.getDecryptedMessage(encryptedMessage);

Generate an AES-256 Key

======================

keytool -genseckey -alias jceksaes -keyalg AES -keysize 256 -storetype JCEKS -keypass mykeypass -storetype jceks -keystore aes-

keystore.jck -storepass mystorepass

Android key generation example

https://developer.android.com/studio/publish/app-signing.html#signing-manually

keytool -genkey -v -keystore my-release-key.jks -keyalg RSA -keysize 2048 -validity 10000 -alias my-alias

View AES-256 Key from command line

======================

mvn clean package // generate executable JAR file java -Dkeystore=main-aes-keystore.jck -Dstorepass=mystorepass -Dalias=jceksaes -Dkeypass=mykeypass -jar target/example-encryption-util.jar <COMMAND like 'showKey'>

// or optionally with Maven (using the above defaults) mvn exec:java

Encrypt / Decrypt AES-256 from command line

======================

// Generate executable JAR with: mvn package

// Ideally the IV passed in (0000000000000000) would be randomly generated java -Dkeystore=main-aes-keystore.jck -Dstorepass=mystorepass -Dalias=jceksaes -Dkeypass=mykeypass -jar target/example-encryption-util.jar encrypt blahblahblah 0000000000000000

java -Dkeystore=main-aes-keystore.jck -Dstorepass=mystorepass -Dalias=jceksaes -Dkeypass=mykeypass -jar target/example-encryption-util.jar decrypt baN3CIAcVgq+AQr7lvKmLw== 0000000000000000

java -Dkeystore=main-aes-keystore.jck -Dstorepass=mystorepass -Dalias=jceksaes -Dkeypass=mykeypass -jar target/example-encryption-util.jar encrypt blahblahblah 0000000000000001

java -Dkeystore=main-aes-keystore.jck -Dstorepass=mystorepass -Dalias=jceksaes -Dkeypass=mykeypass -jar target/example-encryption-util.jar decrypt Wcaov8LNN4GJvp1bvOTJ0g== 0000000000000001

Other references

===================

Android integration frameworks (See https://www.whatsapp.com/security/WhatsApp-Security-Whitepaper.pdf )

AESCrypt Android (https://github.com/quantum-fusion/AESCrypt-Android)

Whisper Systems Android encrypt (https://github.com/quantum-fusion/libsignal-service-java)

quantum-fusion Copyright 2018 - Use of this code and it's concepts are considered a Proof-of-concept and should not be used directly in any environment