LS47 implemented, needs linting
This commit is contained in:
parent
ace8121d0e
commit
0259ed8314
src/core
148
src/core/lib/LS47.mjs
Normal file
148
src/core/lib/LS47.mjs
Normal file
@ -0,0 +1,148 @@
|
||||
/**
|
||||
* @author n1073645 [n1073645@gmail.com]
|
||||
* @copyright Crown Copyright 2020
|
||||
* @license Apache-2.0
|
||||
*/
|
||||
|
||||
import OperationError from "../errors/OperationError.mjs";
|
||||
|
||||
let letters = "_abcdefghijklmnopqrstuvwxyz.0123456789,-+*/:?!'()";
|
||||
let tiles = [];
|
||||
|
||||
export function init_tiles() {
|
||||
for (let i = 0; i < 49; i++)
|
||||
tiles.push([letters.charAt(i), [Math.floor(i/7), i % 7]]);
|
||||
}
|
||||
|
||||
function rotate_down(key, col, n) {
|
||||
let lines = [];
|
||||
for (let i = 0; i < 7; i++)
|
||||
lines.push(key.slice(i*7, (i + 1) * 7));
|
||||
let lefts = [];
|
||||
let mids = [];
|
||||
let rights = [];
|
||||
lines.forEach((element) => {
|
||||
lefts.push(element.slice(0, col));
|
||||
mids.push(element.charAt(col));
|
||||
rights.push(element.slice(col+1));
|
||||
});
|
||||
n = (7 - n % 7) % 7;
|
||||
mids = mids.slice(n).concat(mids.slice(0, n));
|
||||
let result = "";
|
||||
for (let i = 0; i < 7; i++)
|
||||
result += lefts[i] + mids[i] + rights[i];
|
||||
return result;
|
||||
}
|
||||
|
||||
function rotate_right(key, row, n) {
|
||||
let mid = key.slice(row * 7, (row + 1) * 7);
|
||||
n = (7 - n % 7) % 7;
|
||||
return key.slice(0, 7 * row) + mid.slice(n) + mid.slice(0, n) + key.slice(7 * (row + 1));
|
||||
}
|
||||
|
||||
function find_ix(letter) {
|
||||
for (let i = 0; i < tiles.length; i++)
|
||||
if (tiles[i][0] === letter)
|
||||
return tiles[i][1];
|
||||
throw new OperationError("Letter " + letter + " is not included in LS47");
|
||||
}
|
||||
|
||||
export function derive_key(password) {
|
||||
let i = 0;
|
||||
let k = letters;
|
||||
for (const c of password) {
|
||||
let [row, col] = find_ix(c);
|
||||
k = rotate_down(rotate_right(k, i, col), i, row);
|
||||
i = (i + 1) % 7;
|
||||
}
|
||||
return k;
|
||||
}
|
||||
|
||||
function check_key(key) {
|
||||
if (key.length !== letters.length)
|
||||
throw new OperationError("Wrong key size");
|
||||
let counts = new Array();
|
||||
for (let i = 0; i < letters.length; i++)
|
||||
counts[letters.charAt(i)] = 0;
|
||||
for (const elem of letters){
|
||||
if (letters.indexOf(elem) === -1)
|
||||
throw new OperationError("Letter " + elem + " not in LS47!");
|
||||
counts[elem]++;
|
||||
if (counts[elem] > 1)
|
||||
throw new OperationError("Letter duplicated in the key!");
|
||||
}
|
||||
}
|
||||
|
||||
function find_pos (key, letter) {
|
||||
let index = key.indexOf(letter);
|
||||
if (index >= 0 && index < 49)
|
||||
return [Math.floor(index/7), index%7];
|
||||
throw new OperationError("Letter " + letter + " is not in the key!");
|
||||
}
|
||||
|
||||
function find_at_pos(key, coord) {
|
||||
return key.charAt(coord[1] + (coord[0] * 7));
|
||||
}
|
||||
|
||||
function add_pos(a, b) {
|
||||
return [(a[0] + b[0]) % 7, (a[1] + b[1]) % 7];
|
||||
}
|
||||
|
||||
function sub_pos(a, b) {
|
||||
let asub = a[0] - b[0];
|
||||
let bsub = a[1] - b[1];
|
||||
return [asub - (Math.floor(asub/7) * 7), bsub - (Math.floor(bsub/7) * 7)];
|
||||
}
|
||||
|
||||
function encrypt(key, plaintext) {
|
||||
check_key(key);
|
||||
let mp = [0, 0];
|
||||
let ciphertext = '';
|
||||
for (const p of plaintext) {
|
||||
let pp = find_pos(key, p);
|
||||
let mix = find_ix(find_at_pos(key, mp));
|
||||
let cp = add_pos(pp, mix);
|
||||
let c = find_at_pos(key, cp);
|
||||
ciphertext += c;
|
||||
key = rotate_right(key, pp[0], 1);
|
||||
cp = find_pos(key, c);
|
||||
key = rotate_down(key, cp[1], 1);
|
||||
mp = add_pos(mp, find_ix(c));
|
||||
}
|
||||
return ciphertext;
|
||||
}
|
||||
|
||||
function decrypt(key, ciphertext) {
|
||||
check_key(key);
|
||||
let mp = [0,0];
|
||||
let plaintext = '';
|
||||
for (const c of ciphertext) {
|
||||
let cp = find_pos(key, c);
|
||||
let mix = find_ix(find_at_pos(key, mp));
|
||||
let pp = sub_pos(cp, mix);
|
||||
let p = find_at_pos(key, pp);
|
||||
|
||||
plaintext += p;
|
||||
key = rotate_right(key, pp[0], 1);
|
||||
cp = find_pos(key, c);
|
||||
key = rotate_down(key, cp[1], 1);
|
||||
mp = add_pos(mp, find_ix(c));
|
||||
}
|
||||
return plaintext;
|
||||
}
|
||||
|
||||
export function encrypt_pad(key, plaintext, signature, padding_size) {
|
||||
init_tiles();
|
||||
check_key(key);
|
||||
let padding = "";
|
||||
for (let i = 0; i < padding_size; i++) {
|
||||
padding += letters.charAt(Math.floor(Math.random() * letters.length));
|
||||
}
|
||||
return encrypt(key, padding+plaintext+'---'+signature);
|
||||
}
|
||||
|
||||
export function decrypt_pad(key, ciphertext, padding_size) {
|
||||
init_tiles();
|
||||
check_key(key);
|
||||
return decrypt(key, ciphertext).slice(padding_size);
|
||||
}
|
58
src/core/operations/LS47Decrypt.mjs
Normal file
58
src/core/operations/LS47Decrypt.mjs
Normal file
@ -0,0 +1,58 @@
|
||||
/**
|
||||
* @author n1073645 [n1073645@gmail.com]
|
||||
* @copyright Crown Copyright 2020
|
||||
* @license Apache-2.0
|
||||
*/
|
||||
|
||||
import Operation from "../Operation.mjs";
|
||||
import * as LS47 from "../lib/LS47.mjs"
|
||||
|
||||
/**
|
||||
* LS47 Decrypt operation
|
||||
*/
|
||||
class LS47Decrypt extends Operation {
|
||||
|
||||
/**
|
||||
* LS47Decrypt constructor
|
||||
*/
|
||||
constructor() {
|
||||
super();
|
||||
|
||||
this.name = "LS47 Decrypt";
|
||||
this.module = "Crypto";
|
||||
this.description = "";
|
||||
this.infoURL = "";
|
||||
this.inputType = "string";
|
||||
this.outputType = "string";
|
||||
this.args = [
|
||||
{
|
||||
name: "Password",
|
||||
type: "string",
|
||||
value: ""
|
||||
},
|
||||
{
|
||||
name: "Padding",
|
||||
type: "number",
|
||||
value: 10
|
||||
}
|
||||
];
|
||||
}
|
||||
|
||||
/**
|
||||
* @param {string} input
|
||||
* @param {Object[]} args
|
||||
* @returns {string}
|
||||
*/
|
||||
run(input, args) {
|
||||
|
||||
this.padding_size = parseInt(args[1], 10);
|
||||
|
||||
LS47.init_tiles();
|
||||
|
||||
let key = LS47.derive_key(args[0]);
|
||||
return LS47.decrypt_pad(key, input, this.padding_size);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
export default LS47Decrypt;
|
63
src/core/operations/LS47Encrypt.mjs
Normal file
63
src/core/operations/LS47Encrypt.mjs
Normal file
@ -0,0 +1,63 @@
|
||||
/**
|
||||
* @author n1073645 [n1073645@gmail.com]
|
||||
* @copyright Crown Copyright 2020
|
||||
* @license Apache-2.0
|
||||
*/
|
||||
|
||||
import Operation from "../Operation.mjs";
|
||||
import * as LS47 from "../lib/LS47.mjs"
|
||||
|
||||
/**
|
||||
* LS47 Encrypt operation
|
||||
*/
|
||||
class LS47Encrypt extends Operation {
|
||||
|
||||
/**
|
||||
* LS47Encrypt constructor
|
||||
*/
|
||||
constructor() {
|
||||
super();
|
||||
|
||||
this.name = "LS47 Encrypt";
|
||||
this.module = "Crypto";
|
||||
this.description = "";
|
||||
this.infoURL = "";
|
||||
this.inputType = "string";
|
||||
this.outputType = "string";
|
||||
this.args = [
|
||||
{
|
||||
name: "Password",
|
||||
type: "string",
|
||||
value: ""
|
||||
},
|
||||
{
|
||||
name: "Padding",
|
||||
type: "number",
|
||||
value: 10
|
||||
},
|
||||
{
|
||||
name: "Signature",
|
||||
type: "string",
|
||||
value: ""
|
||||
}
|
||||
];
|
||||
}
|
||||
|
||||
/**
|
||||
* @param {string} input
|
||||
* @param {Object[]} args
|
||||
* @returns {string}
|
||||
*/
|
||||
run(input, args) {
|
||||
|
||||
this.padding_size = parseInt(args[1], 10);
|
||||
|
||||
LS47.init_tiles();
|
||||
|
||||
let key = LS47.derive_key(args[0]);
|
||||
return LS47.encrypt_pad(key, input, args[2], this.padding_size);
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
export default LS47Encrypt;
|
Loading…
Reference in New Issue
Block a user