From 789ca3e743fe84936965b757c685385ce5751de7 Mon Sep 17 00:00:00 2001
From: Kierre <vel@riseup.net>
Date: Wed, 10 Sep 2025 23:57:35 -0400
Subject: [PATCH] Allow Vona to receive invites, and add validation to
 make_join

---
 src/globals.py | 32 +++++++++++++---------
 src/s2s.py     | 73 ++++++++++++++++++++++++++++++++------------------
 2 files changed, 66 insertions(+), 39 deletions(-)

diff --git a/src/globals.py b/src/globals.py
index c3b60bd..22f89cd 100644
--- a/src/globals.py
+++ b/src/globals.py
@@ -6,7 +6,7 @@ import json
 import re
 import os
 
-vona_version = "1.2.4"
+vona_version = "1.2.5"
 
 
 def canonical_json(value):
@@ -28,23 +28,29 @@ def sign_json(data):
 	decoded_key = base64.b64decode(base64_key)
 	signing_key = nacl.signing.SigningKey(decoded_key)
 
-	signed_message = signing_key.sign(canonical_json(data))
+	unsigned_keys = {key: data[key] for key in list(data.keys()) if key == "unsigned"}
+	for key in unsigned_keys:
+		del data[key]
 
+	signed_message = signing_key.sign(canonical_json(data))
 	signature = signed_message.signature
 
 	key_version = parts[1]
 	signature_base64 = base64.b64encode(signature).decode("utf-8").rstrip("=")
 
-	signed_json = {
-		**data,
-		"signatures": {
-			config.server_name: {
-				f"ed25519:{key_version}": signature_base64,
-			},
-		},
-	}
+	new_signature = {f"ed25519:{key_version}": signature_base64}
 
-	return signed_json
+	if "signatures" in data:
+		data["signatures"][config.server_name] = {
+			**data["signatures"].get(config.server_name, {}),
+			**new_signature,
+		}
+	else:
+		data["signatures"] = {config.server_name: new_signature}
+
+	data.update(unsigned_keys)
+
+	return data
 
 
 def make_event_id():
@@ -91,7 +97,7 @@ def make_auth_header(destination, method, path, content=None) -> str:
 
 	authorization_headers = []
 
-	for key, sig in signed_json["signatures"][origin_name].items():
+	for key, sig in signed_json["signatures"][config.server_name].items():
 		authorization_headers.append(
 			bytes(
 				'X-Matrix origin="%s",destination="%s",key="%s",sig="%s"'
@@ -104,4 +110,4 @@ def make_auth_header(destination, method, path, content=None) -> str:
 			)
 		)
 
-	return ("Authorization", authorization_headers[0])
+	return authorization_headers[0]
diff --git a/src/s2s.py b/src/s2s.py
index 5c069d6..4b147db 100644
--- a/src/s2s.py
+++ b/src/s2s.py
@@ -139,8 +139,15 @@ def send_join_v1(roomId, eventId):
 def send_join_v2(roomId, eventId):
 	return jsonify(send_join(request, roomId))
 
-@server.route('/_matrix/federation/v1/make_join/<roomId>/<userId>') 
+@server.route('/_matrix/federation/v1/make_join/<roomId>/<userId>')
 def make_join(roomId, userId):
+	if 2 not in request.args.getlist("ver"):
+		return jsonify({
+			"errcode": "M_INCOMPATIBLE_ROOM_VERSION",
+			"error": "Your homeserver does not support the features required to join this room.",
+			"room_version": invite_data["room_version"]
+		}), 400
+
 	return jsonify({
 		"event": {
 			"content": {
@@ -200,7 +207,7 @@ def user_devices(user):
 		"devices": [],
 		"stream_id": the_funny_number,
 		"user_id": f"@vona:{server_name}"
-})
+	})
 
 @server.route('/_matrix/federation/v1/user/keys/query', methods=['POST'])
 def user_keys():
@@ -210,35 +217,49 @@ def user_keys():
 # https://spec.matrix.org/v1.15/server-server-api/#inviting-to-a-room
 @server.route('/_matrix/federation/v2/invite/<room>/<txnId>', methods=['PUT'])
 def invite_user_v2(room, txnId):
-	# This endpoint is not allowed for room
-	# versions over v2 as per spec, so any
-	# invites received here can be discarded
-	# safely.
-
-	return jsonify({
-		"errcode": "M_INCOMPATIBLE_ROOM_VERSION",
-		"error": "Vona only supports room version 2.",
-		"room_version": str(the_funny_number)
-	}), 400
+	return invite_user(request.data.decode('utf-8'), 2)
 
 @server.route('/_matrix/federation/v1/invite/<room>/<txnId>', methods=['PUT'])
-def invite_user(room, txnId):
-	# TODO: Sign provided JSON and return it.
+def invite_user_v1(room, txnId):
+	return invite_user(request.data.decode('utf-8'), 1)
 
-	data = request.data.decode('utf-8')
-	invite_data = json.loads(data)
+def invite_user(data, endpVer):
+	try:
+		invite_data = json.loads(data)
+	except:
+		return jsonify({"errcode":"M_NOT_JSON","error":"Content not JSON."}), 400
 
-	if "room_version" in invite_data:
-		if invite_data["room_version"] != "2":
-			return jsonify({
-				"errcode": "M_INCOMPATIBLE_ROOM_VERSION",
-				"error": "Vona only supports room version 2.",
-				"room_version": invite_data["room_version"]
-			})
-
-	# Placeholder
-	abort(500)
+	if "event" in invite_data:
+		if "room_version" in invite_data:
+			if invite_data["room_version"] != "2":
+				return jsonify({
+					"errcode": "M_INCOMPATIBLE_ROOM_VERSION",
+					"error": "Vona only supports room version 2.",
+					"room_version": invite_data["room_version"]
+				}), 400
+			else:
+				if "content" in invite_data["event"]:
+					if "membership" in invite_data["event"]["content"] and invite_data["event"]["content"]["membership"] == "invite":
+						if endpVer == 1:
+							return jsonify([
+								200,
+								{"event": globals.sign_json(invite_data["event"])}
+							])
+						else:
+							return jsonify({"event": globals.sign_json(invite_data["event"]), "room_version": "2"})
+					else:
+						print("membership is NOT an invitation, or it is missing.")
+				else:
+					print("event does not have content")
+		else:
+			print("data does have room version")
+	else:
+		print("data does have event")
 
+	return jsonify({
+		"errcode": "M_FORBIDDEN",
+		"error": "Invalid invitation PDU"
+	}), 403
 
 @server.route('/_matrix/federation/v1/hierarchy/<roomId>')
 def space_hierachy(roomId):