Common Keyring Implementation Infrastructure

keyring_common library includes modules that can be used in various keyring implementation.

This library provides implementation of following:

1. A JSON configuration file reader and parser
2. A data reader/writer using JSON as format
3. A backup file based file reader/writer
4. Sensitive data container
5. Metadata - Used to uniquely identify sensitive data
6. A wrapper to define extension over sensitive data E.g. ID as provided by key management server
7. An in-memory cache to store Metadata OR {Metadata, Data}
8. An iterator over cache
9. Operations class to interface services APIs with implementation
10. AES encryption/decryption operations
11. Set of utility functions such as random data generator, hex converter etc.

Following diagram shows interactions between various parts of keyring_common library and how they can be used to implement a keyring component.

The diagram uses a file based backend as example and how it can use various modules provided by keyring_common library.