1.7 KiB
SeedPass Specification
Key Hierarchy
SeedPass derives a hierarchy of keys from a single BIP-39 parent seed using HKDF:
- Master Key –
HKDF(seed, "seedpass:v1:master") - KEY_STORAGE – used to encrypt vault data.
- KEY_INDEX – protects the metadata index.
- KEY_PW_DERIVE – deterministic password generation.
- KEY_TOTP_DET – deterministic TOTP secrets.
Each context string keeps derived keys domain separated.
KDF Parameters
Passwords are protected with PBKDF2-HMAC-SHA256. The default work factor is
50,000 iterations but may be adjusted via the settings slider. The config
stores a KdfConfig structure with the chosen iteration count, algorithm name,
and the current spec version (CURRENT_KDF_VERSION = 1). Argon2 is available
with a default time_cost of 2 when selected.
Message Formats
SeedPass synchronizes profiles over Nostr using three event kinds:
- Manifest (
30070) – high level snapshot description and current version. - Snapshot Chunk (
30071) – compressed, encrypted portions of the vault. - Delta (
30072) – incremental changes since the last snapshot.
Events encode JSON and include tags for checksums, fingerprints, and timestamps.
Versioning
Configuration and KDF schemas are versioned so clients can migrate older profiles. Nostr events carry a version field in the manifest, and the software follows semantic versioning for releases.
Memory Protection
SeedPass encrypts sensitive values in memory and attempts to wipe them when no longer needed. This zeroization is best-effort only; Python's memory management may retain copies of decrypted data. Critical cryptographic operations may move to a Rust/WASM module in the future to provide stronger guarantees.