constructor()

in modules/raw-aes-keyring-browser/src/raw_aes_keyring_browser.ts [65:140]

• 54 lines of code
• 3 McCabe index (conditional complexity)

  constructor(input: RawAesKeyringWebCryptoInput) {
    super()
    const { keyName, keyNamespace, masterKey, wrappingSuite, utf8Sorting } =
      input
    /* Precondition: AesKeyringWebCrypto needs identifying information for encrypt and decrypt. */
    needs(keyName && keyNamespace, 'Identifying information must be defined.')
    /* Precondition: RawAesKeyringWebCrypto requires a wrappingSuite to be a valid RawAesWrappingSuite. */
    const wrappingMaterial = new WebCryptoRawAesMaterial(wrappingSuite)
      /* Precondition: unencryptedMasterKey must correspond to the WebCryptoAlgorithmSuite specification.
       * Note: the KeyringTrace and flag are _only_ set because I am reusing an existing implementation.
       * See: raw_aes_material.ts in @aws-crypto/raw-keyring for details
       */
      .setCryptoKey(masterKey, {
        keyNamespace,
        keyName,
        flags: KeyringTraceFlag.WRAPPING_KEY_GENERATED_DATA_KEY,
      })

    if (utf8Sorting === undefined) {
      readOnlyProperty(this, '_utf8Sorting', false)
    } else {
      readOnlyProperty(this, '_utf8Sorting', utf8Sorting)
    }
    // default will be false
    const { serializeEncryptionContext } = serializeFactory(fromUtf8, {
      utf8Sorting: this._utf8Sorting,
    })
    const _wrapKey = async (material: WebCryptoEncryptionMaterial) => {
      /* The AAD section is uInt16BE(length) + AAD
       * see: https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/message-format.html#header-aad
       * However, the RAW Keyring wants _only_ the ADD.
       * So, I just slice off the length.
       */
      const aad = serializeEncryptionContext(material.encryptionContext).slice(
        2
      )
      const { keyNamespace, keyName } = this

      return aesGcmWrapKey(
        keyNamespace,
        keyName,
        material,
        aad,
        wrappingMaterial
      )
    }

    const _unwrapKey = async (
      material: WebCryptoDecryptionMaterial,
      edk: EncryptedDataKey
    ) => {
      /* The AAD section is uInt16BE(length) + AAD
       * see: https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/message-format.html#header-aad
       * However, the RAW Keyring wants _only_ the ADD.
       * So, I just slice off the length.
       */
      const aad = serializeEncryptionContext(material.encryptionContext).slice(
        2
      )
      const { keyNamespace, keyName } = this

      return aesGcmUnwrapKey(
        keyNamespace,
        keyName,
        material,
        wrappingMaterial,
        edk,
        aad
      )
    }

    readOnlyProperty(this, 'keyName', keyName)
    readOnlyProperty(this, 'keyNamespace', keyNamespace)
    readOnlyProperty(this, '_wrapKey', _wrapKey)
    readOnlyProperty(this, '_unwrapKey', _unwrapKey)
  }