Function prepareAsymmetricKey

lib/internal/crypto/keys.js:552–631

(key, ctx, name = 'key')

function prepareAsymmetricKey(key, ctx, name = 'key') {
  if (isKeyObject(key)) {
    // Best case: A key object, as simple as that.
    const type = getKeyObjectType(key);
    validateAsymmetricKeyType(type, ctx, key);
    return { data: getKeyObjectHandle(key) };
  }
  if (isCryptoKey(key)) {
    emitDEP0203();
    validateAsymmetricKeyType(getCryptoKeyType(key), ctx, key);
    return { data: getCryptoKeyHandle(key) };
  }
  if (isStringOrBuffer(key)) {
    // Expect PEM by default, mostly for backward compatibility.
    return { format: kKeyFormatPEM, data: getArrayBufferOrView(key, name) };
  }
  if (typeof key === 'object') {
    const { key: data, encoding, format } = key;

    // The 'key' property can be a KeyObject as well to allow specifying
    // additional options such as padding along with the key.
    if (isKeyObject(data)) {
      const type = getKeyObjectType(data);
      validateAsymmetricKeyType(type, ctx, data);
      return { data: getKeyObjectHandle(data) };
    }
    if (isCryptoKey(data)) {
      emitDEP0203();
      validateAsymmetricKeyType(getCryptoKeyType(data), ctx, data);
      return { data: getCryptoKeyHandle(data) };
    }
    if (format === 'jwk') {
      validateObject(data, `${name}.key`);
      return { data, format: kKeyFormatJWK };
    } else if (format === 'raw-public' || format === 'raw-private' ||
               format === 'raw-seed') {
      if ((ctx === kConsumePrivate || ctx === kCreatePrivate) &&
          format === 'raw-public') {
        throw new ERR_INVALID_ARG_VALUE(`${name}.format`, format);
      }
      if (!isArrayBufferView(data) && !isAnyArrayBuffer(data)) {
        throw new ERR_INVALID_ARG_TYPE(
          `${name}.key`,
          ['ArrayBuffer', 'Buffer', 'TypedArray', 'DataView'],
          data);
      }
      validateString(key.asymmetricKeyType, `${name}.asymmetricKeyType`);
      if (key.asymmetricKeyType === 'ec') {
        validateString(key.namedCurve, `${name}.namedCurve`);
      }
      const rawFormat = parseKeyFormat(format, undefined, `${name}.format`);
      return {
        data: getArrayBufferOrView(data, `${name}.key`),
        format: rawFormat,
        type: key.asymmetricKeyType,
        namedCurve: key.namedCurve ?? null,
      };
    }