J-Crypt

By JayMar921

Encryption/Decryption - University Project

J-Crypt is a Java Program that encrypt/decrypts a String. You can use your own key for strong encryption, there is also an option for generating a key. For best Encryption, I highly recommend to make your own keys that is 15 up characters in length, it should contain Symbols, Upper/Lower case Characters and numbers. example: Th!$key1$N0t$3cur3d_54. The more characters you add, the complexity of character obfuscation increases.

If you are using windows

• install git and download this. Run it with Powershell

Clone

• git clone https://github.com/jaymar921/J-Crypt

go to directory

• cd J-Crypt

Run the Jar

There are two options to run the Jar file

• run the executeJar.sh
• run it in console with this command java -jar JCrypt.jar -cli -ansi

Options

• Encrypt and Decrypt text option, the String will be typed by the user. The encryption and decription will use the key that was generated/entered upon program start.
• Encrypt and Decrypt file option, the user will provide an absolute path for the file to use. The encryption and decription will use the key that was generated/entered upon program start.
• Try Decrypt text option, the String will be typed by the user, the user can provide a key dictionary or just use random for decryption process to start.
• Try Decrypt file option, it will require an absolute path for the file to use, the user can use a key dictionary or random keys for decryption process, you can provide a word dictionary that is space separated for matching purpose. You can set the match percentage, 5% to 100%, I recommend at least (80%)

NOTE:

• use the 'Try Decrypt Text/File' option if you think that the encrypted file uses the program generated key.

Use this program in your system?

Maven Repository

<repositories>
	<repository>
		 <id>jitpack.io</id>
		 <url>https://jitpack.io</url>
	</repository>
</repositories>

Maven Dependency

<dependency>
	 <groupId>com.github.jaymar921</groupId>
	 <artifactId>J-Crypt</artifactId>
	 <version>-41f854c657-1</version>
</dependency>

Gradle, put this at the end of your repositories

allprojects {
	repositories {
		...
		maven { url 'https://jitpack.io' }
	}
}

Gradle, add the dependency

dependencies {
	 implementation 'com.github.jaymar921:J-Crypt:-41f854c657-1'
}

Using the Encryptor

Encryptor encryptor; //create a variable encryptor from Encryptor class
encryptor = new Encryptor(8); // Generates a random key with 8 characters, it prompts when it generates a key
encryptor = new Encryptor(8, true); // Generates a random key with 8 characters, it will not prompt when it generates a key
encryptor = new Encryptor("Anonymous155"); // Provides a key 'Anonymous155', the program promts if it's a good key else it will generate a random
encryptor = new Encryptor("Anonymous155", true); // Provides a key 'Anonymous155', the program will not prompt if its a good key, it will not generate a random key

Encrypt a string

String message = "Hello World"; //'Hello World' will be the test message to encrypt
String encrypted_message = encryptor.getEncryption(message); // the getEncryption(str) returns the encrypted value from the string argument
System.out.println(encrypted_message); //print the encrypted message

Encrypted message of Hello World will be 58 29 36 36 119 § 73 119 42 36 28 using the key Anonymous155

Decrypt a string

String message = "58 29 36 36 119 § 73 119 42 36 28"; //'58 29 36 36 119 § 73 119 42 36 28' will be the test message to decrypt
String decrypted_message = encryptor.getDecryption(message); //the getDecryption(str) returns the decrypted value from the string argument
System.out.println(decrypted_message); //print the decrypted message

Decrypted message of 58 29 36 36 119 § 73 119 42 36 28 will be Hello World using the key Anonymous155

Using HexConvert

you can use hex values as a key

/*
  Using the hex value as a key, passing true on second parameter to turn off
  key checking
*/
String hex_key = HexConvert.toHex("Anonymous155"); //Convert String to hex values
encryptor = new Encryptor(hex_key, true);
/*
  Convert back the hex value to original String
*/
String original_string = HexConvert.fromHex("416e6f6e796d6f7573313535");