svelte-kit-cookie-session/crypto.js

⚒️ Encrypted 'stateless' cookie sessions for SvelteKit

import { aes_256_gcm } from '@noble/ciphers/webcrypto/aes';
import { randomBytes } from '@noble/ciphers/webcrypto/utils';
import { utf8ToBytes, hexToBytes, bytesToHex, bytesToUtf8, concatBytes } from '@noble/ciphers/utils';
export async function encrypt(key, nonce, data) {
    const cipher = aes_256_gcm(key, nonce);
    const ciphertext = await cipher.encrypt(utf8ToBytes(JSON.stringify(data)));
    return bytesToHex(concatBytes(nonce, ciphertext));
}
export async function decrypt(key, encryptedString) {
    const ciphertext = hexToBytes(encryptedString);
    const nonce = ciphertext.subarray(0, 12);
    const ciphertextWithoutNonce = ciphertext.subarray(12);
    const cipher = aes_256_gcm(key, nonce);
    return JSON.parse(bytesToUtf8(await cipher.decrypt(ciphertextWithoutNonce)));
}
export function getKey(secret) {
    if (typeof secret === 'string') {
        return utf8ToBytes(secret);
    }
    if (secret instanceof Uint8Array) {
        return secret;
    }
    if (secret instanceof Uint16Array) {
        return new Uint8Array(secret.buffer);
    }
    if (secret instanceof ArrayBuffer) {
        return new Uint8Array(secret);
    }
    if (secret instanceof Buffer) {
        return new Uint8Array(secret.buffer);
    }
    throw new Error('Invalid secret type');
}
export function generateNonce() {
    return randomBytes(12);
}