This project implements a configuration provider, primarily intended for .NET Core applications, which supports loading AES encrypted Json files, as well as a desktop editor that allows you to create and edit these encrypted files. Files are encrypted utilizing certificates installed on the local machine so the configuration files are portable to any machine you can move the certs to.

I wrote this library because ASP.NET Core doesn't have a good option for protecting your configuration outside of Azure. ASP.NET Core Data Protection isn't really intended for long term configuration storage and portability. This can also replace the use of the "Manage User Secrets" feature in Visual Studio.

You can add the Nuget package to your project, named Hex2bit.AspNetCore.EncryptedConfig (currently pre-release), which can also be found here: https://www.nuget.org/packages/Hex2bit.NetCore.EncryptedConfig/

In your application, you'd specify an encrypted config file to load through the ConfigurationBuilder using the new AddEncryptedConfigFile method.

IConfigurationRoot config = new ConfigurationBuilder()  // config builder
  .AddEncryptedConfigFile(                              // add encrypted config
  new EncryptedConfigurationOptions                     // config options
  {
    ConfigFilename = "settings.ejson",                  // encrypted config file
    Thumbprint = "123456...abcdef"                      // certificate thumbprint
  })
  .Build();

There are a number of ways to configure how to find and load the encrypted file config using the EncryptedConfigurationOptions class. All of the options allow you to specify a specific value and/or an environment variable to look in to find the value (those ending in Env). Below are all the possible configuration options.

• ConfigFilename or ConfigFilenameEnv: filename of the configuration file to load
• Thumbprint or ThumbprintEnv: the thumbprint of the certificate to use to decrypte the configuration file
• StoreLocation or StoreLocationEnv: the certificate store location to search in for the certificate
• StoreName or StoreNameEnv: the certificate store name to search in for the certificate
• ReloadOnChange or ReloadOnChangeEnv: if the configuration file should be reloaded if it is changed
• Optional or OptionalEnv: if this configuration file is optional

Note, environment configuration options will take precedence over the non-environment configuration settings. This allows you to use the environment variables to specify configuration settings, but also provide a fallback value in the configuration in case the environment variable isn't found. For example:

ConfigFilenameEnv = "SettingsFile",       // environment variable "SettingsFile" is expected to have the config file location
ConfigFileName = "falback_settings.ejson" // fallback config file to load

Under the Releases of this GitHub project you will find the latest installer for the desktop editor. https://github.com/hex2bit/NetCore.EncryptedConfig/releases

The editor is pretty basic but allows you to edit files that get saved using AES 256 encryption, utilizing certificates installed on your machine. Files with the extensions of .ejson and .ejs are mapped to the program, so it is recommended to save your files with one of those two extensions. You can even edit those files in Visual Studio just by double clicking on them.

The editor will also remember the certificate that was last successfully used to edit a file, and tries to be smart about tracking that. After you edited a file once, you can usually edit it again, even if your project folder moves due to branching/etc., without having to specify the certificate a second time.

This project is still a work in progress and I have yet to use it in any kind of production level projects, so expect some changes and bugs. The Nuget package is currently published as pre-release to limit its exposure, which I know can cause problems with some build tools.