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add new operations: AES Key Wrap/Unwrap With Padding
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‎src/core/config/Categories.json

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"Citrix CTX1 Decode",
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"AES Key Wrap",
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"AES Key Unwrap",
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"AES Key Wrap With Padding",
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"AES Key Unwrap With Padding",
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"Pseudo-Random Number Generator",
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"Enigma",
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"Bombe",

‎src/core/operations/AESKeyUnwrapWithPadding.mjs

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/**
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* @author aosterhage [aaron.osterhage@gmail.com]
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* @copyright Crown Copyright 2025
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* @license Apache-2.0
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*/
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import Operation from "../Operation.mjs";
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import OperationError from "../errors/OperationError.mjs";
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import Utils from "../Utils.mjs";
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import { toHexFast } from "../lib/Hex.mjs";
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import forge from "node-forge";
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/**
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* AES Key Unwrap With Padding operation
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*/
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class AESKeyUnwrapWithPadding extends Operation {
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/**
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* AESKeyUnwrapWithPadding constructor
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*/
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constructor() {
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super();
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this.name = "AES Key Unwrap With Padding";
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this.module = "Ciphers";
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this.description = "Decryptor for a key wrapping algorithm defined in RFC 3394 combined with a padding convention defined in RFC 5649.";
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this.infoURL = "https://wikipedia.org/wiki/Key_wrap";
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this.inputType = "string";
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this.outputType = "string";
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this.args = [
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{
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"name": "Key (KEK)",
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"type": "toggleString",
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"value": "",
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"toggleValues": ["Hex", "UTF8", "Latin1", "Base64"]
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},
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{
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"name": "Input",
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"type": "option",
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"value": ["Hex", "Raw"]
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},
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{
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"name": "Output",
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"type": "option",
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"value": ["Hex", "Raw"]
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},
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];
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}
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/**
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* @param {string} input
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* @param {Object[]} args
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* @returns {string}
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*/
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run(input, args) {
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const kek = Utils.convertToByteString(args[0].string, args[0].option),
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inputType = args[1],
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outputType = args[2];
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if (kek.length !== 16 && kek.length !== 24 && kek.length !== 32) {
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throw new OperationError("KEK must be either 16, 24, or 32 bytes (currently " + kek.length + " bytes)");
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}
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input = Utils.convertToByteString(input, inputType);
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if (input.length % 8 !== 0 || input.length < 16) {
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throw new OperationError("input must be 8n (n>=2) bytes (currently " + input.length + " bytes)");
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}
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const decipher = forge.cipher.createDecipher("AES-ECB", kek);
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let output, aiv;
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if (input.length === 16) {
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// Special case where the unwrapped data is one 64-bit block.
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decipher.start();
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decipher.update(forge.util.createBuffer(input));
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decipher.finish();
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output = decipher.output.getBytes();
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aiv = output.substring(0, 8);
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output = output.substring(8, 16);
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} else {
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// Otherwise, follow the unwrapping process from RFC 3394 (AESKeyUnwrap operation).
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const cipher = forge.cipher.createCipher("AES-ECB", kek);
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cipher.start();
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cipher.update(forge.util.createBuffer(""));
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cipher.finish();
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const paddingBlock = cipher.output.getBytes();
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let A = input.substring(0, 8);
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const R = [];
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for (let i = 8; i < input.length; i += 8) {
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R.push(input.substring(i, i + 8));
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}
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let cntLower = R.length >>> 0;
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let cntUpper = (R.length / ((1 << 30) * 4)) >>> 0;
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cntUpper = cntUpper * 6 + ((cntLower * 6 / ((1 << 30) * 4)) >>> 0);
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cntLower = cntLower * 6 >>> 0;
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for (let j = 5; j >= 0; j--) {
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for (let i = R.length - 1; i >= 0; i--) {
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const aBuffer = Utils.strToArrayBuffer(A);
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const aView = new DataView(aBuffer);
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aView.setUint32(0, aView.getUint32(0) ^ cntUpper);
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aView.setUint32(4, aView.getUint32(4) ^ cntLower);
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A = Utils.arrayBufferToStr(aBuffer, false);
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decipher.start();
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decipher.update(forge.util.createBuffer(A + R[i] + paddingBlock));
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decipher.finish();
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const B = decipher.output.getBytes();
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A = B.substring(0, 8);
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R[i] = B.substring(8, 16);
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cntLower--;
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if (cntLower < 0) {
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cntUpper--;
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cntLower = 0xffffffff;
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}
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}
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}
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output = R.join("");
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aiv = A;
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}
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// Get the unpadded length from the AIV (which is the MLI). Remove the padding from the output.
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const unpaddedLength = Utils.byteArrayToInt(Utils.strToByteArray(aiv.substring(4, 8)), "big");
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output = output.substring(0, unpaddedLength);
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if (outputType == "Hex") {
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output = toHexFast(Utils.strToArrayBuffer(output));
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}
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return output;
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}
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}
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export default AESKeyUnwrapWithPadding;

‎src/core/operations/AESKeyWrapWithPadding.mjs

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/**
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* @author aosterhage [aaron.osterhage@gmail.com]
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* @copyright Crown Copyright 2025
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* @license Apache-2.0
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*/
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import Operation from "../Operation.mjs";
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import OperationError from "../errors/OperationError.mjs";
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import Utils from "../Utils.mjs";
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import { toHexFast } from "../lib/Hex.mjs";
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import forge from "node-forge";
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/**
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* AES Key Wrap With Padding operation
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*/
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class AESKeyWrapWithPadding extends Operation {
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/**
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* AESKeyWrapWithPadding constructor
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*/
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constructor() {
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super();
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this.name = "AES Key Wrap With Padding";
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this.module = "Ciphers";
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this.description = "A key wrapping algorithm defined in RFC 3394 combined with a padding convention defined in RFC 5649.<br><br>The padding convention defined in RFC 5649 eliminates the requirement that the length of the key to be wrapped be a multiple of 64 bits, allowing a key of any practical length to be wrapped.";
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this.infoURL = "https://wikipedia.org/wiki/Key_wrap";
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this.inputType = "string";
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this.outputType = "string";
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this.args = [
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{
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"name": "Key (KEK)",
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"type": "toggleString",
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"value": "",
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"toggleValues": ["Hex", "UTF8", "Latin1", "Base64"]
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},
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{
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"name": "Input",
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"type": "option",
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"value": ["Hex", "Raw"]
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},
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{
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"name": "Output",
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"type": "option",
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"value": ["Hex", "Raw"]
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},
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];
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}
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/**
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* @param {string} input
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* @param {Object[]} args
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* @returns {string}
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*/
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run(input, args) {
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const kek = Utils.convertToByteString(args[0].string, args[0].option),
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inputType = args[1],
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outputType = args[2];
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if (kek.length !== 16 && kek.length !== 24 && kek.length !== 32) {
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throw new OperationError("KEK must be either 16, 24, or 32 bytes (currently " + kek.length + " bytes)");
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}
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input = Utils.convertToByteString(input, inputType);
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if (input.length <= 0) {
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throw new OperationError("input must be > 0 bytes");
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}
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// Construct the "Alternative Initial Value" (AIV).
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const aiv = "\xa6\x59\x59\xa6" + Utils.byteArrayToChars(Utils.intToByteArray(input.length, 4, "big"));;
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// Pad the input as needed.
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const isMultipleOf8 = (input.length % 8) === 0;
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const paddedLength = input.length + (isMultipleOf8 ? 0 : (8 - (input.length % 8)));
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input = input.padEnd(paddedLength, "\0");
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// Get the cipher ready and disable PKCS#7 padding.
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const cipher = forge.cipher.createCipher("AES-ECB", kek);
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cipher.mode.pad = false;
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let output;
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if (paddedLength === 8) {
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// Special case where the padded input is one 64-bit block.
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cipher.start();
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cipher.update(forge.util.createBuffer(aiv + input));
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cipher.finish();
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output = cipher.output.getBytes();
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} else {
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// Otherwise, follow the wrapping process from RFC 3394 (AESKeyWrap operation).
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let A = aiv;
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const R = [];
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for (let i = 0; i < input.length; i += 8) {
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R.push(input.substring(i, i + 8));
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}
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let cntLower = 1, cntUpper = 0;
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for (let j = 0; j < 6; j++) {
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for (let i = 0; i < R.length; i++) {
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cipher.start();
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cipher.update(forge.util.createBuffer(A + R[i]));
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cipher.finish();
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const B = cipher.output.getBytes();
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const msbBuffer = Utils.strToArrayBuffer(B.substring(0, 8));
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const msbView = new DataView(msbBuffer);
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msbView.setUint32(0, msbView.getUint32(0) ^ cntUpper);
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msbView.setUint32(4, msbView.getUint32(4) ^ cntLower);
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A = Utils.arrayBufferToStr(msbBuffer, false);
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R[i] = B.substring(8, 16);
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cntLower++;
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if (cntLower > 0xffffffff) {
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cntUpper++;
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cntLower = 0;
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}
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}
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}
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output = A + R.join("");
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}
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if (outputType == "Hex") {
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output = toHexFast(Utils.strToArrayBuffer(output));
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}
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return output;
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}
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}
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export default AESKeyWrapWithPadding;

‎tests/operations/index.mjs

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import TestRegister from "../lib/TestRegister.mjs";
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import "./tests/AESKeyWrap.mjs";
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import "./tests/AESKeyWrapWithPadding.mjs";
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import "./tests/AlternatingCaps.mjs";
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import "./tests/AvroToJSON.mjs";
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import "./tests/BaconCipher.mjs";

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