modules: Start an m.room.name module w/ length check conforms hook.

ircd/m.cc

@@ -219,6 +219,7 @@ ircd::m::module_names
 	"m_room_history_visibility",
 	"m_room_join_rules",
 	"m_room_member",
+	"m_room_name",
 	"m_room_third_party_invite",
 	"m_room_message",
 	"m_room_power_levels",

modules/Makefile.am

@@ -144,6 +144,7 @@ m_room_server_acl_la_SOURCES = m_room_server_acl.cc
 m_room_third_party_invite_la_SOURCES = m_room_third_party_invite.cc
 m_room_redaction_la_SOURCES = m_room_redaction.cc
 m_room_bootstrap_la_SOURCES = m_room_bootstrap.cc
+m_room_name_la_SOURCES = m_room_name.cc
 m_init_bootstrap_la_SOURCES = m_init_bootstrap.cc
 m_init_backfill_la_SOURCES = m_init_backfill.cc
 m_listen_la_SOURCES = m_listen.cc
@@ -196,6 +197,7 @@ m_module_LTLIBRARIES = \
 	m_room_redaction.la \
 	m_room_server_acl.la \
 	m_room_bootstrap.la \
+	m_room_name.la \
 	m_init_bootstrap.la \
 	m_init_backfill.la \
 	m_listen.la \

modules/m_room_name.cc

@@ -0,0 +1,66 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2019 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.
+
+namespace ircd::m
+{
+	static void room_name_length_conform(const event &, vm::eval &);
+	extern hookfn<vm::eval &> room_name_length_conform_hookfn;
+	extern const size_t room_name_length_max;
+}
+
+ircd::mapi::header
+IRCD_MODULE
+{
+	"Matrix m.room.name"
+};
+
+/// Spec sez in c2s 13.2.1.3 m.room.name MUST NOT exceed 255 bytes.
+decltype(ircd::m::room_name_length_max)
+ircd::m::room_name_length_max
+{
+	255
+};
+
+decltype(ircd::m::room_name_length_conform_hookfn)
+ircd::m::room_name_length_conform_hookfn
+{
+	room_name_length_conform,
+	{
+		{ "_site",      "vm.conform"   },
+		{ "type",       "m.room.name"  },
+		{ "state_key",  ""             },
+	}
+};
+
+void
+ircd::m::room_name_length_conform(const m::event &event,
+                                  m::vm::eval &)
+{
+	assert(at<"type"_>(event) == "m.room.name");
+
+	const auto &content
+	{
+		json::get<"content"_>(event)
+	};
+
+	const json::string &name
+	{
+		content.get("name")
+	};
+
+	if(size(name) > room_name_length_max)
+		throw vm::error
+		{
+			vm::fault::INVALID,
+			"m.room.name content.name is %zu characters longer than the %zu allowed.",
+			size(name) - room_name_length_max,
+			room_name_length_max,
+		};
+}