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Copius Cipher Chain Cryptography Library
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Overview
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This document describes the architecture for the **CCC Rust Crypto Provider**,
the first of three milestones in delivering hardware-grade cryptography to the
LetUsMsg application.

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Repository                           What ships                  Depends on
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``ccc_rust``                         Pure Rust crypto library    wolfSSL (vendored)
``ccc_dart_plugin``                  Flutter plugin + Dart API   ``ccc_rust`` (git/semver)
``letusmsg`` (existing app)          App integration             ``ccc_dart_plugin`` package
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Guiding Principles
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1. Every provider reports its own capabilities at runtime — no compile-time
   hard-coding of ``available: true/false``.
2. Algorithm IDs in Rust map 1-to-1 to the integer constants in
   ``cipher_constants.dart`` — zero Dart changes needed when wiring up.
3. Key material is zeroed on drop (``zeroize`` crate) everywhere.
4. A conformance test suite validates NIST/RFC vectors for every algorithm
   before any provider is marked ``available``.
5. The library has no runtime dependency on Flutter; it is consumable by any
   FFI host (Flutter plugin, Python tests, CLI tools).