@li0ard/kalyna/dist/modes/mac.js

Kalyna (DSTU 7624:2014) cipher implementation in pure TypeScript

import { xor } from "@li0ard/gost3413/dist/utils";
import { pad } from "../padding";
/**
 * Compute CMAC
 * @param cipherClass Initialized cipher class
 * @param in_ Data to be authenticated
 */
export const cmac = (cipherClass, in_, q = 16) => {
    let data = in_.slice();
    let zeroBlock = new Uint8Array(cipherClass.blockSize);
    if (data.length % cipherClass.blockSize !== 0) {
        data = pad(data, cipherClass.blockSize);
        zeroBlock[0] = 1;
    }
    let Kd = cipherClass.encrypt(zeroBlock);
    let c = new Uint8Array(cipherClass.blockSize);
    const numBlocks = data.length / cipherClass.blockSize;
    for (let i = 0; i < numBlocks - 1; i++) {
        const blockStart = i * cipherClass.blockSize;
        const block = data.slice(blockStart, blockStart + cipherClass.blockSize);
        c = xor(c, block);
        c = cipherClass.encrypt(c);
    }
    const lastBlockStart = (numBlocks - 1) * cipherClass.blockSize;
    const lastBlock = data.slice(lastBlockStart, lastBlockStart + cipherClass.blockSize);
    c = cipherClass.encrypt(xor(xor(c, lastBlock), Kd));
    return c.slice(0, q);
};