slip-plate 0.1.0

A seed plate scanner and parser tool

SLIP-P - Shamir DEK Plates

SLIP-P is a small Python demo that shows how to split DEKs (128/192/256-bit) with Shamir secret sharing and render OneKey-style plates with a small checksum.

This repository was refactored into modular components (CLI, checksum, plate renderer, Shamir wrappers, and crypto helpers) and includes unit tests.

Installation

Quick (no editable install):

python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt pytest
PYTHONPATH=. pytest -q

Recommended (editable install so package imports work automatically):

python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt pytest
# then (optional) install editable if you added pyproject/setup.cfg
pip install -e .
pytest -q

If you don't want to install, setting PYTHONPATH=. before pytest or running the CLI via python -m slip_plate.cli will work.

Usage

This will generate a 256-bit DEK, split it into Shamir shares, print the plates and then recover the DEK to decrypt the message.

Run the CLI/demo:

python -m slip_plate.cli --dek-size 256 --parts 3 --threshold 2

Run the example runner:

python -m examples.example_run --dek-size 256 --parts 3 --threshold 2

Example OneKey-style Plate

Below is a randomized example output for a KEK share plate (128-bit DEK, 2-of-3 Shamir):

=== Shares OneKey-style ===

=== KEK Share 1 ===
     2 1     │         │        
     0 0 5 2 │ 1       │        
     4 2 1 5 │ 2 6 3 1 │        
     8 4 2 6 │ 8 4 2 6 │ 8 4 2 1
    ─────────────────────────────
 1 | ○ ● ● ● │ ● ○ ○ ● │ ● ● ○ ○ │
 2 | ○ ○ ● ○ │ ○ ○ ○ ○ │ ○ ○ ● ○ │
 . | . . . . | . . . . | . . . . |
 . | . . . . | . . . . | . . . . |
 . | . . . . | . . . . | . . . . |
11 | ○ ○ ○ ● │ ● ● ● ○ │ ○ ○ ● ○ │
12 | ● ● ○ ○ │ ● ● ○ ● │ ● ○ ○ ○ │
    ─────────────────────────────

Dots (…) represent truncated rows for brevity.

Security Model

• Plates are generated once and stored offline
• DEKs are reconstructed from a quorum of shares during encryption or decryption
• Nonces are unique per encryption and embedded in the ciphertext
• No DEK is stored digitally outside memory during use

Tests

Run all tests:

pytest -q

Run a single test file:

pytest tests/test_shamir.py -q

Notes and caveats

• Tests include a basic end-to-end flow that encrypts data, splits the DEK, recovers it and decrypts to verify correctness.
• The plate renderer uses ANSI symbols/colors for terminal output.
• This is a demo / research tool - treat outputs as examples and review the code and cryptographic choices before using in production.
• Keep printed plates physically secure; the checksum helps detect transcription errors but is not a replacement for proper key management.

Contributions welcome - open a PR or an issue on the repo if you have improvements or questions.