Cryptographic Primitives

Single source of truth for all crypto used in b1e55ed.

Current Implementation (v2)

Purpose	Primitive	Library	Notes
Identity signing	Ed25519	cryptography	Event signing, karma intents
Key derivation	Argon2id (19 MiB, 2 iter)	argon2-cffi	Memory-hard, GPU-resistant
At-rest encryption	AES-256-GCM	cryptography	Authenticated encryption
Hash chain	SHA-256	hashlib	Event integrity
Canonical serialization	JSON (sorted keys, compact)	json	Deterministic hashing
Vanity grinding	secp256k1 + Keccak-256	eth-account	Forge identity

Legacy Support (v1 — read-only)

Purpose	v1 Primitive	Status
KDF	PBKDF2-HMAC-SHA256 (480K iter)	Read-only (for loading old identity files)
Encryption	Fernet (AES-128-CBC + HMAC-SHA256)	Read-only (for loading old vaults)

New writes always use v2. Old files are automatically readable.

Migration

b1e55ed identity migrate (planned): loads v1 identity, re-saves as v2
For now: re-saving any identity automatically upgrades to v2

Threat Model

Threat	Mitigation
Local file compromise	At-rest encryption (Fernet/AES-256-GCM)
Password brute force	PBKDF2 480K iter → Argon2id (memory-hard)
GPU attacks on KDF	Argon2id (v2 target)
Key in memory	Python heap — no mlock yet. Planned for SEC1.
Swap/core dump	Not mitigated. Planned for SEC1.
Backup compromise	Encrypted at rest + password
Supply chain	Pinned dependencies (uv.lock)
Hash chain tampering	SHA-256 chain + signed genesis (FIX1)

Files

File	Crypto Used
`engine/security/identity.py`	PBKDF2, Fernet, Ed25519, HKDF
`engine/security/keystore.py`	PBKDF2, Fernet
`engine/core/database.py`	SHA-256 (hash chain)
`engine/core/models.py`	SHA-256 (event hash)
`engine/integrations/forge.py`	secp256k1, Keccak-256

Whitepaper technical