@unvision/jose/src/lib/jws/algorithms/hmac.algorithm.js

Implementation of the RFCs of the JOSE Working Group.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.HS512 = exports.HS384 = exports.HS256 = void 0;
const crypto_1 = require("crypto");
const invalid_jsonwebkey_exception_1 = require("../../exceptions/invalid-jsonwebkey.exception");
const invalid_jsonwebsignature_exception_1 = require("../../exceptions/invalid-jsonwebsignature.exception");
const jsonwebsignature_algorithm_1 = require("./jsonwebsignature.algorithm");
/**
 * Implementation of the JSON Web Signature HMAC Algorithm.
 */
class HmacAlgorithm extends jsonwebsignature_algorithm_1.JsonWebSignatureAlgorithm {
    /**
     * Instantiates a new JSON Web Signature HMAC Algorithm to Sign and Verify Messages.
     *
     * @param keySize Size of the Secret accepted by the JSON Web Signature HMAC Algorithm.
     */
    constructor(keySize) {
        const bitSize = keySize << 3;
        super(`HS${bitSize}`, `SHA${bitSize}`, 'oct');
        this.keySize = keySize;
    }
    /**
     * Signs a Message with the provided JSON Web Key.
     *
     * @param message Message to be Signed.
     * @param key JSON Web Key used to Sign the provided Message.
     * @returns Resulting Signature of the provided Message.
     */
    async sign(message, key) {
        this.validateJsonWebKey(key);
        const cryptoKey = key['cryptoKey'];
        const signature = (0, crypto_1.createHmac)(this.hash, cryptoKey).update(message).digest();
        return signature;
    }
    /**
     * Checks if the provided Signature matches the provided Message based on the provide JSON Web Key.
     *
     * @param signature Signature to be matched against the provided Message.
     * @param message Message to be matched against the provided Signature.
     * @param key JSON Web Key used to verify the Signature and Message.
     */
    async verify(signature, message, key) {
        this.validateJsonWebKey(key);
        const calculatedSignature = await this.sign(message, key);
        if (!(0, crypto_1.timingSafeEqual)(signature, calculatedSignature)) {
            throw new invalid_jsonwebsignature_exception_1.InvalidJsonWebSignatureException();
        }
    }
    /**
     * Checks if the provided JSON Web Key can be used by the JSON Web Signature HMAC Algorithm.
     *
     * @param key JSON Web Key to be checked.
     * @throws {InvalidJsonWebKeyException} The provided JSON Web Key is invalid.
     */
    validateJsonWebKey(key) {
        super.validateJsonWebKey(key);
        if (Buffer.from(key.k, 'base64url').length < this.keySize) {
            throw new invalid_jsonwebkey_exception_1.InvalidJsonWebKeyException(`The size of the OctKey Secret must be at least ${this.keySize} bytes.`);
        }
    }
}
/**
 * HMAC using SHA-256.
 */
exports.HS256 = new HmacAlgorithm(32);
/**
 * HMAC using SHA-384.
 */
exports.HS384 = new HmacAlgorithm(48);
/**
 * HMAC using SHA-512.
 */
exports.HS512 = new HmacAlgorithm(64);
//# sourceMappingURL=hmac.algorithm.js.map