andream16 / gocrackerino

Go Meet in The Middle Key Cracker

GoCrackerino

Golang Key Cracker Which Implements Meet In the Middle Strategy.

Given a known cipher-text and a known plain-text, it finds two keys k1 and k2 in a way that Ek1(plain) == Dk2(cipher) where E is the encryption function and D is the decryption function.

It tries all the possible keys in the range of 24/28/32 bits and prints which are the keys to be used for the encryption and decryption.

Keys can only be 6/7/8 Digits HEX and Cipher/Plain can only be 16 Digits HEX.

This cracker was written in Golang since I needed to run both Encryption and Decryption in parallel and goroutines made it easy.

What you need to run the project:

- Go   : ~1.7
- Ocaml: ~4.03.0
- AWK  : ~4.0.1
- Grep : ~2.x

Download the project, extract the contents of sp-network for challenge mitm.zip, then run make on its folder, two executables and more files will be generated. Move encrypt and decrypt executables to the main project's folder or just make sure to specify their paths on go-crackerino.go.

You can run encryption using: ./encrypt -s key cipherText and decryption using ./decrypt -s key plainText.

- 24-bit:   000000 -   FFFFFF
- 28-bit:  0000000 -  FFFFFFF
- 32-bit: 00000000 - FFFFFFFF

Plain/Cipher couples to be used to test the application:

- 24-bit: C330C9CBD01DFBA0 - E10C65124518DB05
- 28-bit: 492A5BB83F8A3F95 - 47090A6AC4A56798
- 32-bit: FFC7C9E5694ABFF7 - 98AC59F25448FFAC

Make sure to have ~20GB of free space for the 32-bit challenge since it will write huge amounts of couples key cipher in a file.

When Ek1(C) == Dk2(P) you found the right keys k1, k2 to read all encrypted messages.