From b04530ebd39f20ebd596963187a3e500077199b3 Mon Sep 17 00:00:00 2001
From: Patrick Cloke <patrickc@matrix.org>
Date: Tue, 18 Jul 2023 11:33:46 -0400
Subject: [PATCH] Fix accepting an invite.

---
 synapse/events/builder.py                         | 13 ++++++++++++-
 synapse/federation/federation_server.py           |  8 ++++++--
 synapse/federation/transport/server/federation.py |  2 +-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index 084b5291eb..d93ed095cc 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -89,6 +89,8 @@ class EventBuilder:
 
     # TODO(LM) If Synapse is acting as a hub-server this should be itself.
     hub_server: Optional[str] = None
+    _lpdu_hashes: Optional[str] = None
+    _lpdu_signatures: Optional[str] = None
 
     internal_metadata: _EventInternalMetadata = attr.Factory(
         lambda: _EventInternalMetadata({})
@@ -187,7 +189,7 @@ class EventBuilder:
         if self._origin_server_ts is not None:
             event_dict["origin_server_ts"] = self._origin_server_ts
 
-        return create_local_event_from_event_dict(
+        event = create_local_event_from_event_dict(
             clock=self._clock,
             hostname=self._hostname,
             signing_key=self._signing_key,
@@ -196,6 +198,13 @@ class EventBuilder:
             internal_metadata_dict=self.internal_metadata.get_dict(),
         )
 
+        if self.room_version.linearized_matrix and self._lpdu_hashes:
+            event.hashes["lpdu"] = self._lpdu_hashes
+        if self.room_version.linearized_matrix and self._lpdu_signatures:
+            event.signatures.update(self._lpdu_signatures)
+
+        return event
+
 
 class EventBuilderFactory:
     def __init__(self, hs: "HomeServer"):
@@ -237,6 +246,8 @@ class EventBuilderFactory:
             redacts=key_values.get("redacts", None),
             origin_server_ts=key_values.get("origin_server_ts", None),
             hub_server=key_values.get("hub_server", None),
+            lpdu_hashes=key_values.get("lpdu_hashes", None),
+            lpdu_signatures=key_values.get("lpdu_signatures", None),
         )
 
 
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 2557ba0f80..69beeb95db 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -1060,6 +1060,7 @@ class FederationServer(FederationBase):
                 "origin_server_ts",
                 "content",
                 "hashes",
+                "signatures",
             ),
         )
 
@@ -1069,12 +1070,15 @@ class FederationServer(FederationBase):
                 raise SynapseError(400, f"LPDU contained {field}", Codes.BAD_JSON)
 
         # Hashes must contain (only) "lpdu".
-        if not isinstance(lpdu_json["hashes"], collections.abc.Mapping):
+        hashes = lpdu_json.pop("hashes")
+        if not isinstance(hashes, collections.abc.Mapping):
             raise SynapseError(400, "Invalid hashes", Codes.BAD_JSON)
-        if lpdu_json["hashes"].keys() != {"lpdu"}:
+        if hashes.keys() != {"lpdu"}:
             raise SynapseError(
                 400, "hashes must contain exactly one key: 'lpdu'", Codes.BAD_JSON
             )
+        lpdu_json["lpdu_hashes"] = hashes["lpdu"]
+        lpdu_json["lpdu_signatures"] = lpdu_json.pop("signatures")
 
         # Validate that the JSON conforms to the specification.
         if room_version.strict_canonicaljson:
diff --git a/synapse/federation/transport/server/federation.py b/synapse/federation/transport/server/federation.py
index 5b98e6656e..34f55b817a 100644
--- a/synapse/federation/transport/server/federation.py
+++ b/synapse/federation/transport/server/federation.py
@@ -625,7 +625,7 @@ class FederationUnstableSendJoinServlet(BaseFederationServerServlet):
         return 200, {
             "event": result["event"],
             "state": result["state"],
-            "auth_chain": result["auth_chain}"],
+            "auth_chain": result["auth_chain"],
         }