comms: implement MAS-backed guest register

This commit is contained in:
Brad Stein 2026-01-07 09:36:45 -03:00
parent 1bcb9baba2
commit a711c450d3
2 changed files with 101 additions and 40 deletions

View File

@ -13,12 +13,13 @@ data:
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib import error, parse, request
SYNAPSE_BASE = os.environ.get("SYNAPSE_BASE", "http://othrys-synapse-matrix-synapse:8008").rstrip("/")
MATRIX_BASE = os.environ.get("MATRIX_BASE", "http://othrys-synapse-matrix-synapse:8008").rstrip("/")
AUTH_BASE = os.environ.get("AUTH_BASE", "http://matrix-authentication-service:8080").rstrip("/")
MAS_ADMIN_BASE = os.environ.get("MAS_ADMIN_BASE", "http://matrix-authentication-service:8081").rstrip("/")
SERVER_NAME = os.environ.get("MATRIX_SERVER_NAME", "live.bstein.dev")
SEEDER_USER = os.environ["SEEDER_USER"]
SEEDER_PASS = os.environ["SEEDER_PASS"]
MAS_ADMIN_CLIENT_ID = os.environ["MAS_ADMIN_CLIENT_ID"]
MAS_ADMIN_CLIENT_SECRET_FILE = os.environ.get("MAS_ADMIN_CLIENT_SECRET_FILE", "/etc/mas/admin-client/client_secret")
# Basic rate limiting (best-effort) to avoid accidental abuse.
# Count requests per client IP over a short window.
@ -50,8 +51,24 @@ data:
payload = {}
return e.code, payload
_seeder_token = None
_seeder_token_at = 0.0
def _form(method, url, *, headers=None, fields=None, timeout=20):
hdrs = {"Content-Type": "application/x-www-form-urlencoded"}
if headers:
hdrs.update(headers)
data = parse.urlencode(fields or {}).encode()
req = request.Request(url, data=data, headers=hdrs, method=method)
try:
with request.urlopen(req, timeout=timeout) as resp:
raw = resp.read()
payload = json.loads(raw.decode()) if raw else {}
return resp.status, payload
except error.HTTPError as e:
raw = e.read()
try:
payload = json.loads(raw.decode()) if raw else {}
except Exception:
payload = {}
return e.code, payload
def _login(user, password):
status, payload = _json(
@ -68,32 +85,46 @@ data:
raise RuntimeError("login_failed")
return payload
def _seeder_access_token(now):
global _seeder_token, _seeder_token_at
if _seeder_token and (now - _seeder_token_at) < 300:
return _seeder_token
payload = _login(SEEDER_USER, SEEDER_PASS)
_seeder_token = payload["access_token"]
_seeder_token_at = now
return _seeder_token
_mas_admin_token = None
_mas_admin_token_at = 0.0
def _create_user(admin_token, localpart, password, displayname):
user_id = f"@{localpart}:{SERVER_NAME}"
def _mas_admin_access_token(now):
global _mas_admin_token, _mas_admin_token_at
if _mas_admin_token and (now - _mas_admin_token_at) < 300:
return _mas_admin_token
with open(MAS_ADMIN_CLIENT_SECRET_FILE, encoding="utf-8") as fh:
client_secret = fh.read().strip()
creds = f"{MAS_ADMIN_CLIENT_ID}:{client_secret}".encode()
basic = base64.b64encode(creds).decode()
status, payload = _form(
"POST",
f"{AUTH_BASE}/oauth2/token",
headers={"Authorization": f"Basic {basic}"},
fields={"grant_type": "client_credentials"},
timeout=20,
)
if status != 200 or "access_token" not in payload:
raise RuntimeError("mas_admin_token_failed")
_mas_admin_token = payload["access_token"]
_mas_admin_token_at = now
return _mas_admin_token
def _mas_create_user(admin_token, username, password):
status, payload = _json(
"PUT",
f"{SYNAPSE_BASE}/_synapse/admin/v2/users/{parse.quote(user_id)}",
"POST",
f"{MAS_ADMIN_BASE}/api/admin/v1/users",
token=admin_token,
body={
"password": password,
"admin": False,
"deactivated": False,
"displayname": displayname,
},
body={"username": username, "password": password},
timeout=25,
)
if status not in (200, 201):
raise RuntimeError("user_create_failed")
return user_id
if status in (200, 201):
return
if status == 409 or payload.get("errcode") == "M_ALREADY_EXISTS":
raise RuntimeError("username_taken")
raise RuntimeError("user_create_failed")
def _generate_localpart():
return "guest-" + secrets.token_hex(6)
@ -101,6 +132,18 @@ data:
def _generate_displayname():
return f"{random.choice(ADJ)}-{random.choice(NOUN)}"
def _set_displayname(access_token, user_id, displayname):
try:
_json(
"PUT",
f"{MATRIX_BASE}/_matrix/client/v3/profile/{parse.quote(user_id)}/displayname",
token=access_token,
body={"displayname": displayname},
timeout=15,
)
except Exception:
return
def _rate_check(ip, now):
win, cnt = _rate.get(ip, (now, 0))
if now - win > RATE_WINDOW_SEC:
@ -168,17 +211,29 @@ data:
# Create a short-lived "guest" account by provisioning a normal user with a random password.
# This keeps MAS/OIDC intact while restoring a no-signup guest UX.
try:
admin_token = _seeder_access_token(now)
displayname = _generate_displayname()
localpart = _generate_localpart()
password = base64.urlsafe_b64encode(secrets.token_bytes(24)).decode().rstrip("=")
user_id = _create_user(admin_token, localpart, password, displayname)
admin_token = _mas_admin_access_token(now)
last = None
for _ in range(3):
localpart = _generate_localpart()
try:
_mas_create_user(admin_token, localpart, password)
break
except RuntimeError as e:
last = str(e)
if last != "username_taken":
raise
else:
raise RuntimeError(last or "user_create_failed")
login_payload = _login(localpart, password)
_set_displayname(login_payload.get("access_token"), login_payload.get("user_id"), displayname)
except Exception:
return self._send_json(502, {"errcode": "M_UNKNOWN", "error": "guest_provision_failed"})
resp = {
"user_id": login_payload.get("user_id") or user_id,
"user_id": login_payload.get("user_id") or f"@{localpart}:{SERVER_NAME}",
"access_token": login_payload.get("access_token"),
"device_id": login_payload.get("device_id"),
"home_server": SERVER_NAME,
@ -192,4 +247,3 @@ data:
if __name__ == "__main__":
main()

View File

@ -35,19 +35,18 @@ spec:
value: "1"
- name: PORT
value: "8080"
- name: SYNAPSE_BASE
- name: MATRIX_BASE
value: http://othrys-synapse-matrix-synapse:8008
- name: AUTH_BASE
value: http://matrix-authentication-service:8080
- name: MAS_ADMIN_BASE
value: http://matrix-authentication-service:8081
- name: MAS_ADMIN_CLIENT_ID
value: 01KDXMVQBQ5JNY6SEJPZW6Z8BM
- name: MAS_ADMIN_CLIENT_SECRET_FILE
value: /etc/mas/admin-client/client_secret
- name: MATRIX_SERVER_NAME
value: live.bstein.dev
- name: SEEDER_USER
value: othrys-seeder
- name: SEEDER_PASS
valueFrom:
secretKeyRef:
name: atlasbot-credentials-runtime
key: seeder-password
- name: RATE_WINDOW_SEC
value: "60"
- name: RATE_MAX
@ -82,6 +81,9 @@ spec:
mountPath: /app/server.py
subPath: server.py
readOnly: true
- name: mas-admin-client
mountPath: /etc/mas/admin-client
readOnly: true
command:
- python
- /app/server.py
@ -92,4 +94,9 @@ spec:
items:
- key: server.py
path: server.py
- name: mas-admin-client
secret:
secretName: mas-admin-client-runtime
items:
- key: client_secret
path: client_secret