MS SQL Persistence Library for KSeF

Overview

We need a standalone library for MS SQL Server persistence to integrate into our system running on .NET Framework 4.8, using the KSeF C# client library. The main focus is on secure hashing and encryption for payloads sent to KSeF, ensuring high priority data integrity and security.

Scope of work

- Develop a .NET Framework 4.8 class library for MS SQL Server persistence.

- Implement SHA-256 hashing for integrity verification of payloads.

- Utilize AES-256 encryption for storing payloads securely.

- Store cryptographic metadata including algorithm, IV, and key ID.

- Ensure ability to decrypt and validate hash upon reading back.

- Integrate library with existing KSeF.Client.

- Provide database schema and scripts for integration.

- Develop repositories/services for storing and retrieving KSeF data.

- Include documentation and usage examples.

References

- https://github.com/CIRFMF/ksef-client-csharp/tree/main

Additional information

The project has a high priority for secure data handling. It's essential to follow encryption standards closely to ensure no secrets or tokens are stored in plain text.

Database platform

MS SQL

Database type

Relational database

Developer expertise

Encryption, SQL