/go-ciphers

Go implementation of: RC4 and ECB / CBC Advanced Encryption Standard (AES) modes of operation

Primary LanguageGoBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

Cipher Implementations

This project is an implementation of the following ciphers - RC4 and two Advanced Encryption Standards (AES) modes of operation, namely ECB and CBC.

Setup

Requirements

Install go

  • cd setup
  • bash install-go.sh
  • export PATH=$PATH:/usr/local/go/bin

Test:

  • go version
  • go env

Uninstall go

  • cd setup
  • sudo bash uninstall-go.sh

RC4

RC4 (also known as ARC4 or ARCFOUR) is a stream cipher. Even though RC4 has now been proven to be cryptographically insecure, it's an interesting cipher that have historically been wildly used in protocols such as WEP.

Build

  • Run go build gorc4/*.go to compile all RC4-related .go files

Run

  • Run ./rc4 -en -in=<input_file> -out=<output_file> -key=<password> for encryption
  • Run ./rc4 -de -in=<input_file> -out=<output_file> -key=<password> for decryption
  • Optionally, you can also:
    • Specify the preferred offset, i.e. number of bytes of the key stream to be discarded in the beginning. By default, offset is set to 1536 bytes as recommended in RFC4345
    • Use the -hex flag to encode encrypted ciphertext to hex encoding, or decode ciphertext for decription from hex encoding.

Help

  • For more info run ./rc4 -h

Tests

This project also implements Test Vectors for the RC4 (RFC6229, see Resource).

  • Navigate to gorc4: cd gorc4
  • Run the tests: go test

References

Other implementations

AES - ECB, CBC

AES is a U.S. National Insitute of Standards and Technology (NIST) specification for the encryption of electronic data. For this project, I chose 2 modes of operation, namely ECB and CBC. CBC is arguably the most common. ECB is not a secure mode of operation and serves solely as demonstration.

Build

  • Run go build goaes/*.go to compile all AES-related .go files

Run

  • Run ./aes -en -in=<input_file> -out=<output_file> -key=<password> for encryption
  • Run ./aes -de -in=<input_file> -out=<output_file> -key=<password> for decryption
  • Optionally, you can also:
    • Specify the preferred mode of operation ("ecb" or "cbc"). By default, "cbc" is used as "ecb" is NOT a secure mode of operation.
    • Use the -hex flag to encode encrypted ciphertext to hex encoding, or decode ciphertext for decription from hex encoding.

Please note that password must be either 128, 192 or 256 bits long, i.e. 16, 24 or 32 bytes / characters long.

Help

  • For more info run ./aes -h

Tests

This project also implements official AES Known Answer Tests (KAT) downloaded from here

  • Download the .zip archive containing KAT files from here. Make sure it is in the goaes/jsontests directory.
  • Run bash setup/aes-tests.sh to extract and parse the KAT files
  • Navigate to goaes: cd goaes
  • Run the tests: go test

References

Other implementations