SeedKeeper

Offline-first, single-device encrypted vault for cryptographic seeds (BIP39, Polyseed, Monero). v1 is an encrypted storage library with a TUI on top — no network, no signing, no blockchain logic.

Status: early. Encryption envelope is specified (spec_final.md) and being implemented; the core types are plaintext scaffolding for now.

Workspace

Crate	Role
seedkeep_core	Keep/Seed types, Envelope (encrypt/decrypt), storage I/O
seedkeep_tui	Presentation only — thin UI over seedkeep_core; no crypto
zeroth	Low-level crypto primitives: Argon2id, XChaCha20-Poly1305, BLAKE3
wally	Seed-format helpers and wordlists; validation deferred

Rule of thumb: all cryptography and disk I/O live in seedkeep_core (via zeroth). The TUI never touches crypto directly.

Design at a glance

• One file per keep (.seedkeep), a self-contained encrypted envelope.
• Each keep has its own random 32-byte master key; the whole Keep (metadata included) is AEAD-sealed under it.
• The master key is wrapped by a KEK derived from the password via Argon2id. The envelope stores a list of wraps, so future device-key / recovery unlocks are a non-breaking addition (v1 ships one password wrap).
• AEAD: XChaCha20-Poly1305. KDF: Argon2id (64 MiB, t=3). Hash: BLAKE3.
• All secret material in memory is held in zeroize types.

Threat model (v1)

Defends against: stolen device/backup + offline brute force, and tampering. Does not defend against a live malicious host or memory extraction — that's a hardware concern (Phase 4).

Build & run

cargo build
cargo run -p seedkeep_tui
cargo test

Roadmap

1. Phase 1 (current): encrypted storage, password unlock, TUI, import/export.
2. Phase 2: cloud backup of encrypted envelopes (dumb blob store, no server crypto), QR airgap transport.
3. Phase 3: signing layer (isolated), device identity, device-key wraps.
4. Phase 4: threshold recovery, hardware-backed keys.

Docs

• spec_final.md — the buildable v1 specification (authoritative).
• agents.md — operational guidance for contributors / coding agents.
• spec_v1.md, spec_v2.md, spec_v3.md — earlier drafts, superseded.