🔐 DEFONEOS Sovereign Data Escrow — Deployment Guide

Deploy the escrow vault on UK-resident servers. Verify no US-affiliated cloud provider holds the encryption keys. Use a UK sovereign cloud or bare-metal in a London/Manchester data centre.

# Verify data residency
curl -s https://ipinfo.io/$(curl -s ifconfig.me)/json | jq '.country'
# Must return "GB"

# Generate custodian Ed25519 keypair
openssl genpkey -algorithm ed25519 -out custodian-private.pem
openssl pkey -in custodian-private.pem -pubout -out custodian-public.pem

Each data record is encrypted with a unique data-encryption-key (DEK), which is itself wrapped by a master key-encryption-key (KEK). The KEK is never stored in plaintext — it is split via Shamir's Secret Sharing into 3 shares held by 3 independent custodians.

# Python reference — encrypt a record
from cryptography.hazmat.primitives.ciphers.aead import AESGCM
import os

dek = AESGCM.generate_key(bit_length=256)
nonce = os.urandom(12)  # 96-bit nonce per NIST SP 800-38D
aesgcm = AESGCM(dek)
ciphertext = aesgcm.encrypt(nonce, plaintext_record, associated_data=sigil)
# Store: nonce + ciphertext + sigil receipt

All inter-service calls (escrow ↔ BFT council ↔ release-gate) use mTLS with Ed25519 client certificates. No plaintext channels.

# nginx config snippet
ssl_protocols TLSv1.3;
ssl_ciphers TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256;
ssl_client_certificate /etc/ssl/custodian-ca.pem;
ssl_verify_client on;
ssl_verify_depth 2;

Every custody event (deposit, access, transfer, release) generates an RFC3161 timestamp token from a trusted TSA, embedded alongside the Ed25519 custodian signature.

# Python — generate RFC3161 timestamp receipt
import requests, hashlib

record_hash = hashlib.sha256(ciphertext).digest()
tsa_response = requests.post(
    'https://timestamp.digicert.com',
    data=record_hash,
    headers={'Content-Type': 'application/timestamp-query'}
)
tsr = tsa_response.content  # RFC3161 TimeStampResp
# Store tsr alongside Ed25519 signature

Release of escrowed data requires two independent custodian approvals. Each approval is an Ed25519 signature over the release request. The gate will not fire until both signatures are verified.

# Release gate validation
def validate_release(release_request, sig1, pubkey1, sig2, pubkey2):
    msg = release_request.canonical_bytes()
    assert Ed25519.verify(msg, sig1, pubkey1), "Custodian 1 signature invalid"
    assert Ed25519.verify(msg, sig2, pubkey2), "Custodian 2 signature invalid"
    assert pubkey1 != pubkey2, "4-eyes violated: same custodian"
    assert release_request.expiry > now(), "Release request expired"
    return True

The 33-agent BFT council continuously monitors escrow activity. Any release can be vetoed: standard veto requires ≥23/33 General votes; emergency veto requires ≥17/33. On veto, the release is frozen and a DEFONEOS red-line check is triggered.

# BFT veto check (runs before release gate fires)
def bft_veto_check(release_id):
    votes = bft_council.poll(release_id, timeout=5.0)
    approve = sum(1 for v in votes if v.state == 'approve')
    reject = sum(1 for v in votes if v.state == 'reject')
    if reject >= 17:
        raise EmergencyVeto(f"BFT emergency veto: {reject}/33 rejected release {release_id}")
    if approve < 23:
        raise InsufficientQuorum(f"BFT quorum not met: {approve}/33 approved")
    return True  # Release proceeds to 4-eyes gate

Every custody event is anchored to a SIGIL receipt — an Ed25519-signed JSON-LD artefact containing the event type, custodian identity, RFC3161 timestamp, cryptographic hash, and BFT vote tally. SIGILs are append-only and published to the audit ledger.