private static AesSivParameters.Variant toVariant(OutputPrefixType outputPrefixType)
      throws GeneralSecurityException {
    if (outputPrefixToVariantMap.containsKey(outputPrefixType)) {
      return outputPrefixToVariantMap.get(outputPrefixType);
    }
    throw new GeneralSecurityException(
        "Unable to parse OutputPrefixType: " + outputPrefixType.getNumber());
  }
Parse LEGACY prefix to CRUNCHY, since they act the same for this type of key
java_src/src/main/java/com/google/crypto/tink/daead/internal/AesSivProtoSerialization.java