absl::StatusOr NewDecryptOp()

in kmsp11/operation/crypter_ops.cc [31:55]

• 25 lines of code
• 7 McCabe index (conditional complexity)

absl::StatusOr<DecryptOp> NewDecryptOp(std::shared_ptr<Object> key,
                                       const CK_MECHANISM* mechanism) {
  switch (mechanism->mechanism) {
    case CKM_RSA_PKCS_OAEP:
      return NewRsaOaepDecrypter(key, mechanism);
    case CKM_AES_GCM:
      return NewInvalidArgumentError(
          absl::StrFormat(
              "Mechanism %#x not supported for AES-GCM decryption, the"
              "Cloud KMS PKCS #11 library defines a custom mechanism"
              "(CKM_CLOUDKMS_AES_GCM) that you can use instead",
              mechanism->mechanism),
          CKR_MECHANISM_INVALID, SOURCE_LOCATION);
    case CKM_CLOUDKMS_AES_GCM:
      return NewAesGcmDecrypter(key, mechanism);
    case CKM_AES_CTR:
      return NewAesCtrDecrypter(key, mechanism);
    case CKM_AES_CBC:
    case CKM_AES_CBC_PAD:
      return NewAesCbcDecrypter(key, mechanism);
    default:
      return InvalidMechanismError(mechanism->mechanism, "decrypt",
                                   SOURCE_LOCATION);
  }
}