jose
Version:
Universal 'JSON Web Almost Everything' - JWA, JWS, JWE, JWT, JWK with no dependencies
34 lines (33 loc) • 1.15 kB
JavaScript
import { KeyObject } from 'crypto';
import { JWEInvalid, JOSENotSupported } from '../util/errors.js';
const checkCekLength = (enc, cek) => {
let expected;
switch (enc) {
case 'A128CBC-HS256':
case 'A192CBC-HS384':
case 'A256CBC-HS512':
expected = parseInt(enc.substr(-3), 10);
break;
case 'A128GCM':
case 'A192GCM':
case 'A256GCM':
expected = parseInt(enc.substr(1, 3), 10);
break;
default:
throw new JOSENotSupported(`Content Encryption Algorithm ${enc} is unsupported either by JOSE or your javascript runtime`);
}
if (cek instanceof Uint8Array) {
if (cek.length << 3 !== expected) {
throw new JWEInvalid('Invalid Content Encryption Key length');
}
return;
}
if (cek instanceof KeyObject && cek.type === 'secret') {
if (cek.symmetricKeySize << 3 !== expected) {
throw new JWEInvalid('Invalid Content Encryption Key length');
}
return;
}
throw new TypeError('Invalid Content Encryption Key type');
};
export default checkCekLength;