@guarani/jose/dist/jwe/algorithms/enc/gcm.js

Implementation of the RFCs of the JOSE Working Group.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.A256GCM = exports.A192GCM = exports.A128GCM = void 0;
const crypto_1 = require("crypto");
const jsonwebencryption_contentencryption_algorithm_1 = require("./jsonwebencryption-contentencryption.algorithm");
/**
 * Implementation of the AES-GCM JSON Web Encryption Content Encryption Algorithm.
 */
class AESGCMContentEncryptionAlgorithm extends jsonwebencryption_contentencryption_algorithm_1.JsonWebEncryptionContentEncryptionAlgorithm {
    /**
     * Instantiates a new AES-GCM JSON Web Encryption Content Encryption to Encrypt and Decrypt a Plaintext.
     *
     * @param algorithm Name of the JSON Web Encryption Content Encryption Algorithm.
     */
    constructor(algorithm) {
        const cekSize = Number.parseInt(algorithm.substring(1, 4));
        super(cekSize, 96, algorithm);
        /**
         * Size of the Authentication Tag in bytes.
         */
        this.authTagLength = 16;
        this.cipherAlgorithm = `aes-${cekSize}-gcm`;
    }
    /**
     * Encrypts the provided Plaintext.
     *
     * @param plaintext Plaintext to be Cncrypted.
     * @param aad Additional Authenticated Data.
     * @param iv Initialization Vector.
     * @param key Content Encryption Key used to Encrypt the provided Plaintext.
     * @returns Resulting Ciphertext and Authentication Tag.
     */
    async encrypt(plaintext, aad, iv, key) {
        this.validateInitializationVector(iv);
        this.validateContentEncryptionKey(key);
        const cipher = (0, crypto_1.createCipheriv)(this.cipherAlgorithm, key, iv, { authTagLength: this.authTagLength });
        cipher.setAAD(aad);
        const ciphertext = Buffer.concat([cipher.update(plaintext), cipher.final()]);
        const tag = cipher.getAuthTag();
        return { ciphertext, tag };
    }
    /**
     * Decrypts the provided Ciphertext back to its original Plaintext.
     *
     * @param ciphertext Ciphertext to be Decrypted.
     * @param aad Additional Authenticated Data.
     * @param iv Initialization Vector.
     * @param tag Authentication Tag.
     * @param key Content Encryption Key used to Decrypt the provided Ciphertext.
     * @returns Resulting Plaintext.
     */
    async decrypt(ciphertext, aad, iv, tag, key) {
        this.validateInitializationVector(iv);
        this.validateContentEncryptionKey(key);
        const decipher = (0, crypto_1.createDecipheriv)(this.cipherAlgorithm, key, iv, { authTagLength: this.authTagLength });
        decipher.setAAD(aad);
        decipher.setAuthTag(tag);
        const decrypted = Buffer.concat([decipher.update(ciphertext), decipher.final()]);
        return decrypted;
    }
}
/**
 * AES GCM using 128-bit key.
 */
exports.A128GCM = new AESGCMContentEncryptionAlgorithm('A128GCM');
/**
 * AES GCM using 192-bit key.
 */
exports.A192GCM = new AESGCMContentEncryptionAlgorithm('A192GCM');
/**
 * AES GCM using 256-bit key.
 */
exports.A256GCM = new AESGCMContentEncryptionAlgorithm('A256GCM');