Add MultiBombe

Runs the Bombe multiple times with different rotor specs.
Edits the core BombeMachine a little to add the ability to switch rotors
without rewiring everything
This commit is contained in:
s2224834 2019-01-10 18:04:02 +00:00
parent 8c757d1e03
commit 3eb44708e5
7 changed files with 411 additions and 13 deletions

View File

@ -104,7 +104,8 @@
"Citrix CTX1 Decode",
"Pseudo-Random Number Generator",
"Enigma",
"Bombe"
"Bombe",
"Multiple Bombe"
]
},
{

View File

@ -92,14 +92,24 @@ class SharedScrambler {
* @param {Object} reflector - The reflector in use.
*/
constructor(rotors, reflector) {
this.reflector = reflector;
this.rotors = rotors;
this.rotorsRev = [].concat(rotors).reverse();
this.lowerCache = new Array(26);
this.higherCache = new Array(26);
for (let i=0; i<26; i++) {
this.higherCache[i] = new Array(26);
}
this.changeRotors(rotors, reflector);
}
/**
* Replace the rotors and reflector in this SharedScrambler.
* This takes care of flushing caches as well.
* @param {Object[]} rotors - List of rotors in the shared state _only_.
* @param {Object} reflector - The reflector in use.
*/
changeRotors(rotors, reflector) {
this.reflector = reflector;
this.rotors = rotors;
this.rotorsRev = [].concat(rotors).reverse();
this.cacheGen();
}
@ -195,13 +205,22 @@ class Scrambler {
*/
constructor(base, rotor, pos, end1, end2) {
this.baseScrambler = base;
this.rotor = rotor;
this.initialPos = pos;
this.rotor.pos += pos;
this.changeRotor(rotor);
this.end1 = end1;
this.end2 = end2;
}
/**
* Replace the rotor in this scrambler.
* The position is reset automatically.
* @param {Object} rotor - New rotor
*/
changeRotor(rotor) {
this.rotor = rotor;
this.rotor.pos += this.initialPos;
}
/**
* Step the rotors forward.
*
@ -304,12 +323,7 @@ export class BombeMachine {
}
this.ciphertext = ciphertext;
this.crib = crib;
// This is ordered from the Enigma fast rotor to the slow, so bottom to top for the Bombe
this.baseRotors = [];
for (const rstr of rotors) {
const rotor = new CopyRotor(rstr, "", "A", "A");
this.baseRotors.push(rotor);
}
this.initRotors(rotors);
this.updateFn = update;
const [mostConnected, edges] = this.makeMenu();
@ -355,6 +369,33 @@ export class BombeMachine {
}
}
/**
* Build Rotor objects from list of rotor wiring strings.
* @param {string[]} rotors - List of rotor wiring strings
*/
initRotors(rotors) {
// This is ordered from the Enigma fast rotor to the slow, so bottom to top for the Bombe
this.baseRotors = [];
for (const rstr of rotors) {
const rotor = new CopyRotor(rstr, "", "A", "A");
this.baseRotors.push(rotor);
}
}
/**
* Replace the rotors and reflector in all components of this Bombe.
* @param {string[]} rotors - List of rotor wiring strings
* @param {Object} reflector - Reflector object
*/
changeRotors(rotors, reflector) {
// At the end of the run, the rotors are all back in the same position they started
this.initRotors(rotors);
this.sharedScrambler.changeRotors(this.baseRotors.slice(1), reflector);
for (const scrambler of this.allScramblers) {
scrambler.changeRotor(this.baseRotors[0].copy());
}
}
/**
* If we have a way of sending status messages, do so.
* @param {string} msg - Message to send.

View File

@ -171,6 +171,7 @@ class PairMapBase {
constructor(pairs, name="PairMapBase") {
// I've chosen to make whitespace significant here to make a) code and
// b) inputs easier to read
this.pairs = pairs;
this.map = {};
if (pairs === "") {
return;

View File

@ -0,0 +1,307 @@
/**
* Emulation of the Bombe machine.
* This version carries out multiple Bombe runs to handle unknown rotor configurations.
*
* @author s2224834
* @copyright Crown Copyright 2019
* @license Apache-2.0
*/
import Operation from "../Operation";
import OperationError from "../errors/OperationError";
import {BombeMachine} from "../lib/Bombe";
import {ROTORS, REFLECTORS, Reflector} from "../lib/Enigma";
/**
* Convenience method for flattening the preset ROTORS object into a newline-separated string.
* @param {Object[]} - Preset rotors object
* @param {number} s - Start index
* @param {number} n - End index
* @returns {string}
*/
function rotorsFormat(rotors, s, n) {
const res = [];
for (const i of rotors.slice(s, n)) {
res.push(i.value);
}
return res.join("\n");
}
/**
* Combinatorics choose function
* @param {number} n
* @param {number} k
* @returns number
*/
function choose(n, k) {
let res = 1;
for (let i=1; i<=k; i++) {
res *= (n + 1 - i) / i;
}
return res;
}
/**
* Bombe operation
*/
class MultipleBombe extends Operation {
/**
* Bombe constructor
*/
constructor() {
super();
this.name = "Multiple Bombe";
this.module = "Default";
this.description = "Emulation of the Bombe machine used to attack Enigma. This version carries out multiple Bombe runs to handle unknown rotor configurations.<br><br>You should test your menu on the single Bombe operation before running it here. See the description of the Bombe operation for instructions on choosing a crib.";
this.infoURL = "https://wikipedia.org/wiki/Bombe";
this.inputType = "string";
this.outputType = "string";
this.args = [
{
"name": "Standard Enigmas",
"type": "populateOption",
"value": [
{
name: "German Service Enigma (First - 3 rotor)",
value: rotorsFormat(ROTORS, 0, 5)
},
{
name: "German Service Enigma (Second - 3 rotor)",
value: rotorsFormat(ROTORS, 0, 8)
},
{
name: "German Service Enigma (Third - 4 rotor)",
value: rotorsFormat(ROTORS, 0, 8)
},
{
name: "German Service Enigma (Fourth - 4 rotor)",
value: rotorsFormat(ROTORS, 0, 8)
},
{
name: "User defined",
value: ""
},
],
"target": 1
},
{
name: "Main rotors",
type: "text",
value: ""
},
{
"name": "Standard Enigmas",
"type": "populateOption",
"value": [
{
name: "German Service Enigma (First - 3 rotor)",
value: ""
},
{
name: "German Service Enigma (Second - 3 rotor)",
value: ""
},
{
name: "German Service Enigma (Third - 4 rotor)",
value: rotorsFormat(ROTORS, 8, 9)
},
{
name: "German Service Enigma (Fourth - 4 rotor)",
value: rotorsFormat(ROTORS, 8, 10)
},
{
name: "User defined",
value: ""
},
],
"target": 3
},
{
name: "4th rotor",
type: "text",
value: ""
},
{
"name": "Standard Enigmas",
"type": "populateOption",
"value": [
{
name: "German Service Enigma (First - 3 rotor)",
value: rotorsFormat(REFLECTORS, 0, 1)
},
{
name: "German Service Enigma (Second - 3 rotor)",
value: rotorsFormat(REFLECTORS, 0, 2)
},
{
name: "German Service Enigma (Third - 4 rotor)",
value: rotorsFormat(REFLECTORS, 2, 3)
},
{
name: "German Service Enigma (Fourth - 4 rotor)",
value: rotorsFormat(REFLECTORS, 2, 4)
},
{
name: "User defined",
value: ""
},
],
"target": 5
},
{
name: "Reflectors",
type: "text",
value: ""
},
{
name: "Crib",
type: "string",
value: ""
},
{
name: "Crib offset",
type: "number",
value: 0
}
];
}
/**
* Format and send a status update message.
* @param {number} nLoops - Number of loops in the menu
* @param {number} nStops - How many stops so far
* @param {number} progress - Progress (as a float in the range 0..1)
*/
updateStatus(nLoops, nStops, progress) {
const msg = `Bombe run with ${nLoops} loops in menu (2+ desirable): ${nStops} stops, ${Math.floor(100 * progress)}% done`;
self.sendStatusMessage(msg);
}
/**
* Early rotor description string validation.
* Drops stepping information.
* @param {string} rstr - The rotor description string
* @returns {string} - Rotor description with stepping stripped, if any
*/
validateRotor(rstr) {
// The Bombe doesn't take stepping into account so we'll just ignore it here
if (rstr.includes("<")) {
rstr = rstr.split("<", 2)[0];
}
// Duplicate the validation of the rotor strings here, otherwise you might get an error
// thrown halfway into a big Bombe run
if (!/^[A-Z]{26}$/.test(rstr)) {
throw new OperationError("Rotor wiring must be 26 unique uppercase letters");
}
if (new Set(rstr).size !== 26) {
throw new OperationError("Rotor wiring must be 26 unique uppercase letters");
}
return rstr;
}
/**
* @param {string} input
* @param {Object[]} args
* @returns {string}
*/
run(input, args) {
const mainRotorsStr = args[1];
const fourthRotorsStr = args[3];
const reflectorsStr = args[5];
let crib = args[6];
const offset = args[7];
// TODO got this far
const rotors = [];
const fourthRotors = [];
const reflectors = [];
for (let rstr of mainRotorsStr.split("\n")) {
rstr = this.validateRotor(rstr);
rotors.push(rstr);
}
if (rotors.length < 3) {
throw new OperationError("A minimum of three rotors must be supplied");
}
if (fourthRotorsStr !== "") {
for (let rstr of fourthRotorsStr.split("\n")) {
rstr = this.validateRotor(rstr);
fourthRotors.push(rstr);
}
}
if (fourthRotors.length === 0) {
fourthRotors.push("");
}
for (const rstr of reflectorsStr.split("\n")) {
const reflector = new Reflector(rstr);
reflectors.push(reflector);
}
if (reflectors.length === 0) {
throw new OperationError("A minimum of one reflector must be supplied");
}
if (crib.length === 0) {
throw new OperationError("Crib cannot be empty");
}
if (offset < 0) {
throw new OperationError("Offset cannot be negative");
}
// For symmetry with the Enigma op, for the input we'll just remove all invalid characters
input = input.replace(/[^A-Za-z]/g, "").toUpperCase();
crib = crib.replace(/[^A-Za-z]/g, "").toUpperCase();
const ciphertext = input.slice(offset);
let update;
if (ENVIRONMENT_IS_WORKER()) {
update = this.updateStatus;
} else {
update = undefined;
}
let bombe = undefined;
let msg;
// I could use a proper combinatorics algorithm here... but it would be more code to
// write one, and we don't seem to have one in our existing libraries, so massively nested
// for loop it is
const totalRuns = choose(rotors.length, 3) * 6 * fourthRotors.length * reflectors.length;
let nRuns = 0;
let nStops = 0;
for (const rotor1 of rotors) {
for (const rotor2 of rotors) {
if (rotor2 === rotor1) {
continue;
}
for (const rotor3 of rotors) {
if (rotor3 === rotor2 || rotor3 === rotor1) {
continue;
}
for (const rotor4 of fourthRotors) {
for (const reflector of reflectors) {
nRuns++;
const runRotors = [rotor1, rotor2, rotor3];
if (rotor4 !== "") {
runRotors.push(rotor4);
}
if (bombe === undefined) {
bombe = new BombeMachine(runRotors, reflector, ciphertext, crib);
msg = `Bombe run on menu with ${bombe.nLoops} loops (2+ desirable). Note: Rotors and rotor positions are listed left to right, ignore stepping and the ring setting, and positions start at the beginning of the crib. One stecker pair is determined. A decryption preview starting at the beginning of the crib and ignoring stepping is also provided. Results:\n`;
} else {
bombe.changeRotors(runRotors, reflector);
}
const result = bombe.run();
nStops += result.length;
if (update !== undefined) {
update(bombe.nLoops, nStops, nRuns / totalRuns);
}
if (result.length > 0) {
msg += `Rotors: ${runRotors.join(", ")}\nReflector: ${reflector.pairs}\n`;
for (const [setting, stecker, decrypt] of result) {
msg += `Stop: ${setting} (plugboard: ${stecker}): ${decrypt}\n`;
}
}
}
}
}
}
}
return msg;
}
}
export default MultipleBombe;

View File

@ -84,6 +84,7 @@ import "./tests/ParseTLV";
import "./tests/Media";
import "./tests/Enigma";
import "./tests/Bombe";
import "./tests/MultipleBombe";
// Cannot test operations that use the File type yet
//import "./tests/SplitColourChannels";

View File

@ -85,7 +85,7 @@ TestRegister.addTests([
{
name: "Bombe: 4 rotor",
input: "LUOXGJSHGEDSRDOQQX",
expectedMatch: /LHSC \(plugboard: SS\)/,
expectedMatch: /LHSC \(plugboard: SS\): HHHSSSGQUUQPKSEKWK/,
recipeConfig: [
{
"op": "Bombe",

View File

@ -0,0 +1,47 @@
/**
* Bombe machine tests.
* @author s2224834
* @copyright Crown Copyright 2019
* @license Apache-2.0
*/
import TestRegister from "../TestRegister";
TestRegister.addTests([
{
name: "Multi-Bombe: 3 rotor",
input: "BBYFLTHHYIJQAYBBYS",
expectedMatch: /LGA \(plugboard: SS\): VFISUSGTKSTMPSUNAK/,
recipeConfig: [
{
"op": "Multiple Bombe",
"args": [
// I, II and III
"User defined", "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R\nAJDKSIRUXBLHWTMCQGZNPYFVOE<F\nBDFHJLCPRTXVZNYEIWGAKMUSQO<W",
"User defined", "",
"User defined", "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
"THISISATESTMESSAGE", 0,
]
}
]
},
/*
* This is too slow to run regularly
{
name: "Multi-Bombe: 4 rotor",
input: "LUOXGJSHGEDSRDOQQX",
expectedMatch: /LHSC \(plugboard: SS\): HHHSSSGQUUQPKSEKWK/,
recipeConfig: [
{
"op": "Multiple Bombe",
"args": [
// I, II and III
"User defined", "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R\nAJDKSIRUXBLHWTMCQGZNPYFVOE<F\nBDFHJLCPRTXVZNYEIWGAKMUSQO<W",
"User defined", "LEYJVCNIXWPBQMDRTAKZGFUHOS", // Beta
"User defined", "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
"THISISATESTMESSAGE", 0,
]
}
]
},
*/
]);