From d2d6ba0f18a81e12b2b44779e7d421bdd7fba8c9 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Tue, 3 Apr 2018 17:16:15 -0700
Subject: [PATCH] modules/federation: Add send_leave endpoint handler.

---
 modules/Makefile.am              |   2 +
 modules/federation/send_leave.cc | 132 +++++++++++++++++++++++++++++++
 2 files changed, 134 insertions(+)
 create mode 100644 modules/federation/send_leave.cc

diff --git a/modules/Makefile.am b/modules/Makefile.am
index b2b34d513..f3a18b2a3 100644
--- a/modules/Makefile.am
+++ b/modules/Makefile.am
@@ -248,6 +248,7 @@ federation_federation_send_join_la_SOURCES = federation/send_join.cc
 federation_federation_state_ids_la_SOURCES = federation/state_ids.cc
 federation_federation_state_la_SOURCES = federation/state.cc
 federation_federation_make_leave_la_SOURCES = federation/make_leave.cc
+federation_federation_send_leave_la_SOURCES = federation/send_leave.cc
 
 federation_module_LTLIBRARIES = \
 	federation/federation_send.la \
@@ -263,6 +264,7 @@ federation_module_LTLIBRARIES = \
 	federation/federation_state_ids.la \
 	federation/federation_state.la \
 	federation/federation_make_leave.la \
+	federation/federation_send_leave.la \
 	###
 
 ###############################################################################
diff --git a/modules/federation/send_leave.cc b/modules/federation/send_leave.cc
new file mode 100644
index 000000000..aaac50c0f
--- /dev/null
+++ b/modules/federation/send_leave.cc
@@ -0,0 +1,132 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice is present in all copies. The
+// full license for this software is available in the LICENSE file.
+
+using namespace ircd;
+
+mapi::header
+IRCD_MODULE
+{
+	"Federation :Send leave event"
+};
+
+const string_view
+send_leave_description
+{R"(
+
+Inject a leave event into a room originating from a server without any joined
+users in that room.
+
+)"};
+
+resource
+send_leave_resource
+{
+	"/_matrix/federation/v1/send_leave/",
+	{
+		send_leave_description,
+		resource::DIRECTORY
+	}
+};
+
+resource::response
+put__send_leave(client &client,
+               const resource::request &request)
+{
+	if(request.parv.size() < 1)
+		throw m::NEED_MORE_PARAMS
+		{
+			"room_id path parameter required"
+		};
+
+	m::room::id::buf room_id
+	{
+		url::decode(request.parv[0], room_id)
+	};
+
+	if(!my_host(room_id.host()))
+		throw m::error
+		{
+			http::FORBIDDEN, "M_INVALID_ROOM_ID",
+			"Can only send_leave for rooms on my host '%s'",
+			my_host()
+		};
+
+	if(request.parv.size() < 2)
+		throw m::NEED_MORE_PARAMS
+		{
+			"event_id path parameter required"
+		};
+
+	m::event::id::buf event_id
+	{
+		url::decode(request.parv[1], event_id)
+	};
+
+	const m::event event
+	{
+		request
+	};
+
+	if(at<"event_id"_>(event) != event_id)
+		throw m::error
+		{
+			http::NOT_MODIFIED, "M_MISMATCH_EVENT_ID",
+			"ID of event in request body does not match path parameter."
+		};
+
+	if(at<"room_id"_>(event) != room_id)
+		throw m::error
+		{
+			http::NOT_MODIFIED, "M_MISMATCH_ROOM_ID",
+			"ID of room in request body does not match path parameter."
+		};
+
+	if(json::get<"type"_>(event) != "m.room.member")
+		throw m::error
+		{
+			http::NOT_MODIFIED, "M_INVALID_TYPE",
+			"Event type must be m.room.member"
+		};
+
+	if(json::get<"membership"_>(event) != "leave")
+		throw m::error
+		{
+			http::NOT_MODIFIED, "M_INVALID_MEMBERSHIP",
+			"Event membership state must be 'leave'."
+		};
+
+	if(unquote(json::get<"content"_>(event).get("membership")) != "leave")
+		throw m::error
+		{
+			http::NOT_MODIFIED, "M_INVALID_CONTENT_MEMBERSHIP",
+			"Event content.membership state must be 'leave'."
+		};
+
+	m::vm::opts vmopts;
+	vmopts.non_conform.set(m::event::conforms::MISSING_PREV_STATE);
+	m::vm::eval eval
+	{
+		event, vmopts
+	};
+
+	return resource::response
+	{
+		client, http::OK
+	};
+}
+
+resource::method
+method_put
+{
+	send_leave_resource, "PUT", put__send_leave,
+	{
+		method_put.VERIFY_ORIGIN
+	}
+};