scalio-connect

Signed calls between the Scalio apps and Compass. One format ("v2", header Scalio-Signature) for every direction:

• Compass -> app: control key K3 on /api/provision/* (replaces the old X-Provision-Control-Signature)
• app -> Compass: instance key on the support intake /api/support/v1/* (planned)

Contract: scalio-docs interfaces/signed-request-v2.md. Decision: scalio-docs ADR 0020.

What is signed

Scalio-Signature: v=2,kid=k3,ts=1793131200,nonce=vector-nonce-0000000001,sig=<base64 Ed25519>

scalio-sig-v2
<kid>
<METHOD>
<audience = receiver origin, e.g. https://acme.eu.scalionexus.com>
<path and query as sent, e.g. /api/provision/admin>
<ts>
<nonce>
<sha256 of the raw body, hex>

Lines joined by \n, no line break at the end. Time window +-300 s, each (kid, nonce) once. Because receiver and path are signed, a captured request does not work on another instance or another endpoint (security review H9).

Usage

from scalio_connect import sign, verify, SignatureError
from scalio_connect.nonces import use_nonce

# sender
headers = sign(private_key, "k3", "POST", "https://acme.eu.scalionexus.com/api/provision/admin", body)

# receiver (raw body bytes, path with query as received)
try:
    v = verify(request.headers["Scalio-Signature"], request.method, path_with_query, body,
               audiences=["https://acme.eu.scalionexus.com"], keys_for=lambda kid: k3_keys if kid == "k3" else [])
except SignatureError:
    raise HTTPException(401)
if not await use_nonce(db, v.kid, v.nonce):
    raise HTTPException(401)

audiences are the receiver's own public origins from its configuration. Do not take them from the Host header.

K3 during the switch

from scalio_connect.k3 import K3Error, audiences_from_env, check_request

try:
    await check_request(db, request.headers, request.method, path_with_query, body,
                        keys=k3_public_keys, audiences=audiences_from_env())
except K3Error as e:
    raise HTTPException(401, str(e))

Accepts v2 and the old X-Provision-* format until the first valid v2 call, then only v2. Before that a failed v2 check falls back to the old format (logged), so a wrong public URL does not lock Compass out. Public URLs come from SCALIO_PUBLIC_URLS, APP_PUBLIC_URL, FRONTEND_URL, PUBLIC_URL.

Development

pip install -e ".[dev]"
ruff check . && pytest -q

tests/vector.json is the shared test vector (throwaway seed). Compass and every app test against the same file. Release: bump pyproject.toml, CHANGELOG line, merge, then "Publish" (cockpit or Actions) with the version, no v.