$ show BcryptNet/bcrypt.net
This repository is a high-quality .NET library implementing the OpenBSD BCrypt password hashing algorithm. It serves as a security-critical dependency for authentication systems, providing robust password hashing, verification, and salt generation. The codebase is multi-targeted, supporting legacy .NET Framework versions (4.6.2+) alongside modern .NET standards (2.0/2.1) and recent runtimes (.NET 8.0, 10.0). It includes specialized extensions for ASP.NET Core Identity, allowing seamless integration into existing authentication pipelines without custom implementation. The architecture prioritizes security through constant-time comparisons, secure memory handling, and thread-safe key schedule management using ThreadLocal storage. The library includes extensive test vectors from the original Java reference implementation to ensure algorithmic correctness across different BCrypt revisions (2a, 2b, 2y, 2x). While the core library is production-ready and widely adopted, the repository exhibits some hygiene issues, including the presence of a signing key file in the root directory and a 'dists/' folder containing legacy binary artifacts, which suggests a mix of automated and manual release processes. For engineers evaluating reuse, this library offers a reliable, well-tested foundation for password security. The Identity extension component is particularly valuable for .NET developers needing to replace default password hashers. However, consumers should be aware of the technical drift regarding legacy framework support and the potential security implications of the repository's artifact management practices.
The LLM identified 4 files worth highlighting for reuse:
The primary public API for the library. Implements HashPassword, Verify, and GenerateSalt methods. Demonstrates high craftsmanship through secure memory handling, constant-time comparison to prevent timing attacks, and support for multiple BCrypt scheme versions. This component is the core reusable asset for any project requiring secure password hashing.
Provides a reusable implementation of IPasswordHasher<TUser> for ASP.NET Core Identity. Allows developers to swap the default password hasher with BCrypt without modifying the Identity infrastructure. This pattern is highly reusable for any .NET Identity-based application needing stronger hashing than default.
Utility class for parsing BCrypt hash strings to extract version, work factor, and salt components. Encapsulates the logic required to validate hash structure and extract metadata for password upgrade logic. This component is reusable for any system needing to interrogate or validate existing BCrypt hashes.
Demonstrates rigorous testing of thread safety for cryptographic operations. Uses ThreadLocal storage for Blowfish key schedules to prevent cross-thread data leakage under high concurrency. This test pattern is a valuable reference for ensuring thread safety in other cryptographic or stateful components.