Subsections

• 1.1 What is Ganzúa?
• 1.2 List of Features

1. Introduction

1.1 What is Ganzúa?

Ganzúa (picklock in Spanish) is a cryptanalysis tool for classical ciphers (monoalphabetic and polyalphabetic) that lets the user define almost completely arbitrary cipher and plain alphabets, allowing for the proper cryptanalysis of cryptograms obtained from non-English texts.

Ganzúa is an internationalized Java application, localized for English and Spanish. In other words, Ganzúa is a platform-independent computer program that can be adapted to various languages and regions without engineering changes, and as of this version it features English and Spanish interfaces from which to choose. It provides an environment for the cryptanalysis of monoalphabetic and polyalphabetic ciphers and was written to be used as a tool in an introductory cryptology course.

Ganzúa is open source software covered by the General Public License (GPL), which grants you many more rights than most software licenses, including access to the source code and freedom to change it.

Ganzúa was written in the Java programming language with the GNU EMACS editor in GNU/Linux and Mac OS X.

1.2 List of Features

• Features present for all ciphers:
  • Use almost arbitrary plain and cipher alphabets.
  • Obtain and display the standard relative frequencies of characters, bigrams and trigrams of languages.
  • Calculate the index of coincidence of cryptograms and languages.
  • Estimate the number of alphabets used to generate a cryptogram, based on the index of coincidence of the ciphertext and the one of the language.
  • Enforced injective character substitution.
  • Save and load ongoing cryptanalysis projects.
• Monoalphabetic cryptanalysis features:
  • Alphabet-wide substitution tools for the Caesar shift cipher and other monoalphabetic ciphers.
  • Obtain and display the relative frequencies of the characters, bigrams and trigrams of cryptograms.
• Polyalphabetic cryptanalysis features:
  • Alphabet-wide substitution tools for the Vigenère or Alberti ciphers.
  • Obtain and display the relative frequencies of the characters ciphered using each alphabet.
  • Perform the Kasiski Test on cryptograms.