From 99c5a56a4f05cd48a2066243bc5e614e3e523d65 Mon Sep 17 00:00:00 2001 From: LoRd_MuldeR Date: Sun, 13 Nov 2022 20:30:35 +0100 Subject: [PATCH] Updated README file. --- README.md | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/README.md b/README.md index 544eef0..fd784e9 100644 --- a/README.md +++ b/README.md @@ -1,5 +1,5 @@ --- -title: "![SlunkCrypt](etc/img/SlunkCrypt-Logo.png)" +title: "![SlunkCrypt 🐔](etc/img/SlunkCrypt-Logo.png)" --- @@ -201,7 +201,14 @@ Here are some examples on how to use the SlunkCrypt command-line application: Encryption algorithm ==================== -SlunkCrypt is based on concepts of the well-known [**Enigma**](https://en.wikipedia.org/wiki/Enigma_machine) machine, but with numerous "modern" improvements, largely inspired by [***“A Modern Rotor Machine”***](https://rdcu.be/cBo8y): +SlunkCrypt is based on concepts of the well-known [**Enigma**](https://en.wikipedia.org/wiki/Enigma_machine) machine, but with significant improvements, largely inspired by [***Ross Anderson – “A Modern Rotor Machine”***](https://rdcu.be/cBo8y). + +A great explanation and visualization of how the *original* Enigma machine works can be found in [***this***](https://www.youtube.com/watch?v=ybkkiGtJmkM) video. + +Overview +-------- + +This section summarizes the improvements that have been implemented in SlunkCrypt: - The original Enigma machine had only *three* (or, in some models, *four*) rotors, plus a static "reflector" wheel. In SlunkCrypt, we uses **256** simulated rotors for an improved security. Furthermore, the original Enigma machine supported only 26 distinct symbols, i.e. the letters `A` to `Z`. In SlunkCrypt, we use **256** distinct symbols, i.e. the byte values `0x00` to `0xFF`, which allows the encryption (and decryption) of arbitrary streams of bytes, rather than just plain text. Of course, SlunkCrypt can encrypt (and decrypt) text files as well. @@ -209,14 +216,14 @@ SlunkCrypt is based on concepts of the well-known [**Enigma**](https://en.wikipe - In the original Enigma machine, the rightmost rotor was moved, by one step, after every symbol. Meanwhile, all other rotors were moved, by one step, *only* when their right-hand neighbor had completed a full turn – much like the odometer in a car. The fact that most of the rotors remained in the same "static" position most of the time was an important weakness of the Enigma machine. Also, the sequence of the Enigma's rotor positions started to repeat after only 16,900 characters. SlunkCrypt employs an improved stepping algorithm, based on a ***linear-feedback shift register* (LSFR)**, ensuring that *all* rotors move frequently and in a "randomized" unpredictable pattern. The rotor positions of SlunkCrypt practically *never* repeat. -- The internal wiring of each of the original Enigma machine's rotors was *fixed*. Each rotor "type" came with a different internal wiring (i.e. permutation). Some models had up to eight rotor "types" to choose from, but only three or four rotors were used at a time. Nonetheless, the internal wiring (i.e. permutation) of each of the supplied rotors was **not** modifiable. This severely restricted the key space of the Enigma machine, as far as the rotors are concerned, because *only* the order of the rotors and the initial position of each rotor could be varied. In SlunkCrypt, a fully *randomized* wiring (i.e. permutation) is generated from the password for each of the 256 simulated rotors. The initial rotor positions are *randomized* as well. +- The internal wiring of each of the original Enigma machine's rotors was *fixed*. Each rotor "type" came with a different internal wiring (i.e. permutation). Some models had up to eight rotor "types" to choose from, but only three or four rotors were used at a time. Nonetheless, the internal wiring (i.e. permutation) of each of the supplied rotors was **not** modifiable. This severely restricted the key space of the Enigma machine, as far as the rotors are concerned, because *only* the order of the rotors and the initial position of each rotor could be varied. In SlunkCrypt, a fully *randomized* wiring (i.e. permutation) is generated from the passphrase for each of the 256 simulated rotors. The initial rotor positions are *randomized* as well. -- SlunkCrypt does **not** currently implement the *plugboard* (“Steckerbrett”) of the original Enigma machine. That is because, even though the plugboard has a large key space, it is just a *fixed* substitution cipher that does *not* contribute much to the cryptographic strength of the Enigma machine. In fact, the plugboard could be "erased" by Welchman's [diagonal board](https://en.wikipedia.org/wiki/Bombe#Stecker_values). +- SlunkCrypt does **not** currently implement the *plugboard* (“Steckerbrett”). Even though the plugboard significantly contributed to the key space of the original Engima machine, it was simply a *fixed* substitution cipher. SlunkCrypt already has a ***much*** bigger key space than that of the original Engine machine, because the number of rotors is substantially larger and because the internal wiring of these rotors is completely key-dependant. Therefore, adding a plugboard would *not* contribute notably to SlunkCrypt's cryptographic strength. Details ------- -This section explains some implementation details of the SlunkCrypt library: +This section explains some crucial implementation details of the SlunkCrypt library: * **DRBG:** The *deterministic random bit generator* (DRBG) employed by SlunkCrypt is called [*Xorwow*](https://en.wikipedia.org/wiki/Xorshift#xorwow), an enhanced variant of *Xorshift* , i.e. a form of *linear-feedback shift registers (LSFR)*.