comms: harden guest register provisioning

services/comms/scripts/guest-register/server.py

@@ -3,6 +3,7 @@ import json
 import os
 import random
 import secrets
+import time
 from http.server import BaseHTTPRequestHandler, HTTPServer
 from urllib import error, parse, request
 
@@ -29,6 +30,20 @@ NOUN = [
     "pine","quartz","reef","ridge","sable","sage","shore","thunder","vale","zephyr",
 ]
 
+def _open_with_retry(req, timeout, attempts=6):
+    last = None
+    for attempt in range(1, attempts + 1):
+        try:
+            return request.urlopen(req, timeout=timeout)
+        except error.HTTPError as e:
+            return e
+        except (error.URLError, TimeoutError, OSError) as e:
+            last = e
+            time.sleep(attempt * 2)
+    if last:
+        raise last
+    raise RuntimeError("request_failed")
+
 def _json(method, url, *, headers=None, body=None, timeout=20):
     hdrs = {"Content-Type": "application/json"}
     if headers:
@@ -37,18 +52,17 @@ def _json(method, url, *, headers=None, body=None, timeout=20):
     if body is not None:
         data = json.dumps(body).encode()
     req = request.Request(url, data=data, headers=hdrs, method=method)
-    try:
+    resp = _open_with_retry(req, timeout)
-        with request.urlopen(req, timeout=timeout) as resp:
+    if isinstance(resp, error.HTTPError):
-            raw = resp.read()
+        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
+        return resp.code, payload
+    raw = resp.read()
+    payload = json.loads(raw.decode()) if raw else {}
+    return resp.status, payload
 
 def _form(method, url, *, headers=None, fields=None, timeout=20):
     hdrs = {"Content-Type": "application/x-www-form-urlencoded"}
@@ -56,18 +70,17 @@ def _form(method, url, *, headers=None, fields=None, timeout=20):
         hdrs.update(headers)
     data = parse.urlencode(fields or {}).encode()
     req = request.Request(url, data=data, headers=hdrs, method=method)
-    try:
+    resp = _open_with_retry(req, timeout)
-        with request.urlopen(req, timeout=timeout) as resp:
+    if isinstance(resp, error.HTTPError):
-            raw = resp.read()
+        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
+        return resp.code, payload
+    raw = resp.read()
+    payload = json.loads(raw.decode()) if raw else {}
+    return resp.status, payload
 
 _admin_token = None
 _admin_token_at = 0.0
@@ -110,12 +123,28 @@ def _admin_api(admin_token, method, path, body=None):
         timeout=20,
     )
 
-def _create_user(admin_token, username):
+def _create_user(admin_token, username, password):
-    status, payload = _admin_api(admin_token, "POST", "/users", {"username": username})
+    payloads = [
-    if status != 201:
+        {
-        return status, None
+            "data": {
-    user = payload.get("data") or {}
+                "type": "user",
-    return status, user.get("id")
+                "attributes": {
+                    "username": username,
+                    "password": password,
+                },
+            }
+        },
+        {"username": username, "password": password},
+        {"username": username},
+    ]
+    for payload in payloads:
+        status, body = _admin_api(admin_token, "POST", "/users", payload)
+        if status in (200, 201):
+            user = body.get("data") or {}
+            return status, user.get("id") or user.get("id")
+        if status == 409:
+            return status, None
+    return status, None
 
 def _set_password(admin_token, user_id, password):
     status, _payload = _admin_api(
@@ -127,20 +156,28 @@ def _set_password(admin_token, user_id, password):
     return status in (200, 204)
 
 def _login_password(username, password):
-    payload = {
+    payloads = [
-        "type": "m.login.password",
+        {
-        "identifier": {"type": "m.id.user", "user": f"@{username}:{SERVER_NAME}"},
+            "type": "m.login.password",
-        "password": password,
+            "identifier": {"type": "m.id.user", "user": f"@{username}:{SERVER_NAME}"},
-    }
+            "password": password,
-    status, data = _json(
+        },
-        "POST",
+        {
-        f"{MAS_BASE}/_matrix/client/v3/login",
+            "type": "m.login.password",
-        body=payload,
+            "identifier": {"type": "m.id.user", "user": username},
-        timeout=20,
+            "password": password,
-    )
+        },
-    if status != 200:
+    ]
-        return None, None
+    for payload in payloads:
-    return data.get("access_token"), data.get("device_id")
+        status, data = _json(
+            "POST",
+            f"{MAS_BASE}/_matrix/client/v3/login",
+            body=payload,
+            timeout=20,
+        )
+        if status == 200:
+            return data.get("access_token"), data.get("device_id")
+    return None, None
 
 def _set_display_name(access_token, user_id, displayname):
     _json(
@@ -224,18 +261,18 @@ class Handler(BaseHTTPRequestHandler):
             admin_token = _mas_admin_access_token(now)
             displayname = _generate_displayname()
 
+            password = secrets.token_urlsafe(18)
             localpart = None
             mas_user_id = None
             for _ in range(5):
                 localpart = _generate_localpart()
-                status, mas_user_id = _create_user(admin_token, localpart)
+                status, mas_user_id = _create_user(admin_token, localpart, password)
-                if status == 201 and mas_user_id:
+                if status in (200, 201) and mas_user_id:
                     break
                 mas_user_id = None
             if not mas_user_id or not localpart:
                 raise RuntimeError("add_user_failed")
 
-            password = secrets.token_urlsafe(18)
             if not _set_password(admin_token, mas_user_id, password):
                 raise RuntimeError("set_password_failed")
             access_token, device_id = _login_password(localpart, password)