Introduction

uacrypt

A Rust implementation of Ukrainian DSTU cryptographic standards — Kalyna (block cipher), Kupyna (hash), Strumok (stream cipher), DSTU 4145 (digital signatures), and DSTU 9041 (asymmetric encryption) — in the spirit of libsodium: hard, safe defaults, hard to misuse, rather than OpenSSL’s flexible-but-easy-to-misconfigure API. Ships as a Rust crate (dstu-core), a CLI (uacrypt), and bindings for eight languages.

Pre-1.0. Not audited. Not a claim of side-channel resistance. dstu-core/uacrypt are on crates.io; the Python, Node.js, and Ruby bindings are on PyPI/npm/ RubyGems too. See docs/CHANGELOG.md for what changed each release and docs/release-readiness.md for the gap analysis against a complete 1.0.

Algorithms in scope

Full scope, architectural decisions, and the libsodium API mapping are in docs/dstu-crypto-project.md. dstu-core also builds in a small/flash-friendly resource profile for constrained MCUs (--features small-tables) — see docs/resource-profiles.md for the trade-off.

Quick start

cargo add dstu-core

#![allow(unused)]
fn main() {
use dstu_core::crypto_secretbox::{seal, open, SecretKey};

let key = SecretKey::generate().expect("OS CSPRNG should not fail");
let sealed = seal(&key, b"message").expect("OS CSPRNG should not fail");
let opened = open(&key, &sealed).expect("authentic ciphertext");
assert_eq!(opened, b"message");
}

Or the CLI, which streams arbitrarily large files with no in-memory cap:

cargo install uacrypt   # or download a prebuilt binary from GitHub Releases
uacrypt keygen --out key.bin
uacrypt encrypt --key key.bin --in message.bin --out sealed.bin
uacrypt decrypt --key key.bin --in sealed.bin --out message.bin

See docs/CLI.md for the full command reference (sign/verify, box-seal/box-open, and the lower-level kalyna-block/ kalyna-ccm tools), and docs.rs for the full library API.

Language bindings

The full crypto_* surface (secretbox/secretstream/sign/auth/kdf/generichash/stream/ pwhash, randombytes, selftest), idiomatic errors, and the same correctness/rejection/misuse test suite, in every language below — not a thin, partial wrapper. The README column is the full per-language docs; the Package column is where you’d actually run an install command.

The C ABI itself (crates/dstu-core-capi, opaque handles, cbindgen-generated header) is what the .NET, Go, and C++ bindings link against directly — usable from any language with a C FFI, not just those three. See docs/bindings-strategy.md for the per-binding design rationale.

Embedded / no_std targets

dstu-core is no_std-compatible from day one (std/alloc/no_std feature flags), and cross-compiles clean for real microcontroller targets (STM32 Cortex-M, ESP32-class RISC-V) with no custom toolchain. That’s a compilation claim, not a real-hardware validation or a side-channel resistance claim — see docs/SECURITY.md for the full threat model.

Status and further reading

• docs/SECURITY.md — threat model and hard constraints
• docs/DECISIONS.md — architectural decisions, with rejected alternatives
• docs/TASKS.md — phase-by-phase task backlog
• docs/release-readiness.md — gap analysis against a libsodium-equivalent 1.0
• Full knowledge base: user137.github.io/uacrypt

Contributing

Pull requests are welcome. See docs/CONTRIBUTING.md for dev environment setup, the test/verification bar (dual-oracle verification, three test categories per primitive), and commit style, and docs/CODE_OF_CONDUCT.md for community standards. Security vulnerabilities go through GitHub Security Advisories, not a public issue — see docs/SECURITY.md “Reporting vulnerabilities”.

License

Dual-licensed under MIT / Apache-2.0, at the user’s choice — the standard for the Rust ecosystem. See LICENSE-MIT and LICENSE-APACHE.