Merge branch 'esmconversion' of https://github.com/artemisbot/CyberChef into esm

src/core/lib/Ciphers.mjs

@@ -0,0 +1,81 @@
+/**
+ * Cipher functions.
+ *
+ * @author Matt C [matt@artemisbot.uk]
+ * @author n1474335 [n1474335@gmail.com]
+ *
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ *
+ */
+import OperationError from "../errors/OperationError";
+import CryptoJS from "crypto-js";
+
+/**
+ * Affine Cipher Encode operation.
+ *
+ * @author Matt C [matt@artemisbot.uk]
+ * @param {string} input
+ * @param {Object[]} args
+ * @returns {string}
+ */
+export function affineEncode(input, args) {
+    const alphabet = "abcdefghijklmnopqrstuvwxyz",
+        a = args[0],
+        b = args[1];
+    let output = "";
+
+    if (!/^\+?(0|[1-9]\d*)$/.test(a) || !/^\+?(0|[1-9]\d*)$/.test(b)) {
+        throw new OperationError("The values of a and b can only be integers.");
+    }
+
+    for (let i = 0; i < input.length; i++) {
+        if (alphabet.indexOf(input[i]) >= 0) {
+            // Uses the affine function ax+b % m = y (where m is length of the alphabet)
+            output += alphabet[((a * alphabet.indexOf(input[i])) + b) % 26];
+        } else if (alphabet.indexOf(input[i].toLowerCase()) >= 0) {
+            // Same as above, accounting for uppercase
+            output += alphabet[((a * alphabet.indexOf(input[i].toLowerCase())) + b) % 26].toUpperCase();
+        } else {
+            // Non-alphabetic characters
+            output += input[i];
+        }
+    }
+    return output;
+}
+
+/**
+ * Generates a polybius square for the given keyword
+ *
+ * @private
+ * @author Matt C [matt@artemisbot.uk]
+ * @param {string} keyword - Must be upper case
+ * @returns {string}
+ */
+export function genPolybiusSquare (keyword) {
+    const alpha = "ABCDEFGHIKLMNOPQRSTUVWXYZ",
+        polArray = `${keyword}${alpha}`.split("").unique(),
+        polybius = [];
+
+    for (let i = 0; i < 5; i++) {
+        polybius[i] = polArray.slice(i*5, i*5 + 5);
+    }
+
+    return polybius;
+}
+
+/**
+ * A mapping of string formats to their classes in the CryptoJS library.
+ *
+ * @private
+ * @constant
+ */
+export const format = {
+    "Hex":     CryptoJS.enc.Hex,
+    "Base64":  CryptoJS.enc.Base64,
+    "UTF8":    CryptoJS.enc.Utf8,
+    "UTF16":   CryptoJS.enc.Utf16,
+    "UTF16LE": CryptoJS.enc.Utf16LE,
+    "UTF16BE": CryptoJS.enc.Utf16BE,
+    "Latin1":  CryptoJS.enc.Latin1,
+};