File

util/adminstream.lua @ 11749:83d6d6a70edf

net.http: fail open if surrounding code does not configure TLS Previously, if surrounding code was not configuring the TLS context used default in net.http, it would not validate certificates at all. This is not a security issue with prosody, because prosody updates the context with `verify = "peer"` as well as paths to CA certificates in util.startup.init_http_client. Nevertheless... Let's not leave this pitfall out there in the open.
author Jonas Schäfer <jonas@wielicki.name>
date Sun, 29 Aug 2021 15:04:47 +0200
parent 10940:18e4e446a76c
child 12094:84fd6a79cda7
line wrap: on
line source

local st = require "util.stanza";
local new_xmpp_stream = require "util.xmppstream".new;
local sessionlib = require "util.session";
local gettime = require "util.time".now;
local runner = require "util.async".runner;
local add_task = require "util.timer".add_task;
local events = require "util.events";
local server = require "net.server";

local stream_close_timeout = 5;

local log = require "util.logger".init("adminstream");

local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";

local stream_callbacks = { default_ns = "xmpp:prosody.im/admin" };

function stream_callbacks.streamopened(session, attr)
	-- run _streamopened in async context
	session.thread:run({ stream = "opened", attr = attr });
end

function stream_callbacks._streamopened(session, attr) --luacheck: ignore 212/attr
	if session.type ~= "client" then
		session:open_stream();
	end
	session.notopen = nil;
end

function stream_callbacks.streamclosed(session, attr)
	-- run _streamclosed in async context
	session.thread:run({ stream = "closed", attr = attr });
end

function stream_callbacks._streamclosed(session)
	session.log("debug", "Received </stream:stream>");
	session:close(false);
end

function stream_callbacks.error(session, error, data)
	if error == "no-stream" then
		session.log("debug", "Invalid opening stream header (%s)", (data:gsub("^([^\1]+)\1", "{%1}")));
		session:close("invalid-namespace");
	elseif error == "parse-error" then
		session.log("debug", "Client XML parse error: %s", data);
		session:close("not-well-formed");
	elseif error == "stream-error" then
		local condition, text = "undefined-condition";
		for child in data:childtags(nil, xmlns_xmpp_streams) do
			if child.name ~= "text" then
				condition = child.name;
			else
				text = child:get_text();
			end
			if condition ~= "undefined-condition" and text then
				break;
			end
		end
		text = condition .. (text and (" ("..text..")") or "");
		session.log("info", "Session closed by remote with error: %s", text);
		session:close(nil, text);
	end
end

function stream_callbacks.handlestanza(session, stanza)
	session.thread:run(stanza);
end

local runner_callbacks = {};

function runner_callbacks:error(err)
	self.data.log("error", "Traceback[c2s]: %s", err);
end

local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};

local function destroy_session(session, reason)
	if session.destroyed then return; end
	session.destroyed = true;
	session.log("debug", "Destroying session: %s", reason or "unknown reason");
end

local function session_close(session, reason)
	local log = session.log or log;
	if session.conn then
		if session.notopen then
			session:open_stream();
		end
		if reason then -- nil == no err, initiated by us, false == initiated by client
			local stream_error = st.stanza("stream:error");
			if type(reason) == "string" then -- assume stream error
				stream_error:tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' });
			elseif type(reason) == "table" then
				if reason.condition then
					stream_error:tag(reason.condition, stream_xmlns_attr):up();
					if reason.text then
						stream_error:tag("text", stream_xmlns_attr):text(reason.text):up();
					end
					if reason.extra then
						stream_error:add_child(reason.extra);
					end
				elseif reason.name then -- a stanza
					stream_error = reason;
				end
			end
			stream_error = tostring(stream_error);
			log("debug", "Disconnecting client, <stream:error> is: %s", stream_error);
			session.send(stream_error);
		end

		session.send("</stream:stream>");
		function session.send() return false; end

		local reason_text = (reason and (reason.name or reason.text or reason.condition)) or reason;
		session.log("debug", "c2s stream for %s closed: %s", session.full_jid or session.ip or "<unknown>", reason_text or "session closed");

		-- Authenticated incoming stream may still be sending us stanzas, so wait for </stream:stream> from remote
		local conn = session.conn;
		if reason_text == nil and not session.notopen and session.type == "c2s" then
			-- Grace time to process data from authenticated cleanly-closed stream
			add_task(stream_close_timeout, function ()
				if not session.destroyed then
					session.log("warn", "Failed to receive a stream close response, closing connection anyway...");
					destroy_session(session);
					conn:close();
				end
			end);
		else
			destroy_session(session, reason_text);
			conn:close();
		end
	else
		local reason_text = (reason and (reason.name or reason.text or reason.condition)) or reason;
		destroy_session(session, reason_text);
	end
end

--- Public methods

local function new_connection(socket_path, listeners)
	local have_unix, unix = pcall(require, "socket.unix");
	if type(unix) ~= "table" then
		have_unix = false;
	end
	local conn, sock;

	return {
		connect = function ()
			if not have_unix then
				return nil, "no unix socket support";
			end
			if sock or conn then
				return nil, "already connected";
			end
			sock = unix.stream();
			sock:settimeout(0);
			local ok, err = sock:connect(socket_path);
			if not ok then
				return nil, err;
			end
			conn = server.wrapclient(sock, nil, nil, listeners, "*a");
			return true;
		end;
		disconnect = function ()
			if conn then
				conn:close();
				conn = nil;
			end
			if sock then
				sock:close();
				sock = nil;
			end
			return true;
		end;
	};
end

local function new_server(sessions, stanza_handler)
	local listeners = {};

	function listeners.onconnect(conn)
		log("debug", "New connection");
		local session = sessionlib.new("admin");
		sessionlib.set_id(session);
		sessionlib.set_logger(session);
		sessionlib.set_conn(session, conn);

		session.conntime = gettime();
		session.type = "admin";

		local stream = new_xmpp_stream(session, stream_callbacks);
		session.stream = stream;
		session.notopen = true;

		session.thread = runner(function (stanza)
			if st.is_stanza(stanza) then
				stanza_handler(session, stanza);
			elseif stanza.stream == "opened" then
				stream_callbacks._streamopened(session, stanza.attr);
			elseif stanza.stream == "closed" then
				stream_callbacks._streamclosed(session, stanza.attr);
			end
		end, runner_callbacks, session);

		function session.data(data)
			-- Parse the data, which will store stanzas in session.pending_stanzas
			if data then
				local ok, err = stream:feed(data);
				if not ok then
					session.log("debug", "Received invalid XML (%s) %d bytes: %q", err, #data, data:sub(1, 300));
					session:close("not-well-formed");
				end
			end
		end

		session.close = session_close;

		session.send = function (t)
			session.log("debug", "Sending[%s]: %s", session.type, t.top_tag and t:top_tag() or t:match("^[^>]*>?"));
			return session.rawsend(tostring(t));
		end

		function session.rawsend(t)
			local ret, err = conn:write(t);
			if not ret then
				session.log("debug", "Error writing to connection: %s", err);
				return false, err;
			end
			return true;
		end

		sessions[conn] = session;
	end

	function listeners.onincoming(conn, data)
		local session = sessions[conn];
		if session then
			session.data(data);
		end
	end

	function listeners.ondisconnect(conn, err)
		local session = sessions[conn];
		if session then
			session.log("info", "Admin client disconnected: %s", err or "connection closed");
			session.conn = nil;
			sessions[conn]  = nil;
		end
	end

	function listeners.onreadtimeout(conn)
		return conn:send(" ");
	end

	return {
		listeners = listeners;
	};
end

local function new_client()
	local client = {
		type = "client";
		events = events.new();
		log = log;
	};

	local listeners = {};

	function listeners.onconnect(conn)
		log("debug", "Connected");
		client.conn = conn;

		local stream = new_xmpp_stream(client, stream_callbacks);
		client.stream = stream;
		client.notopen = true;

		client.thread = runner(function (stanza)
			if st.is_stanza(stanza) then
				if not client.events.fire_event("received", stanza) and not stanza.attr.xmlns then
					client.events.fire_event("received/"..stanza.name, stanza);
				end
			elseif stanza.stream == "opened" then
				stream_callbacks._streamopened(client, stanza.attr);
				client.events.fire_event("connected");
			elseif stanza.stream == "closed" then
				client.events.fire_event("disconnected");
				stream_callbacks._streamclosed(client, stanza.attr);
			end
		end, runner_callbacks, client);

		client.close = session_close;

		function client.send(t)
			client.log("debug", "Sending: %s", t.top_tag and t:top_tag() or t:match("^[^>]*>?"));
			return client.rawsend(tostring(t));
		end

		function client.rawsend(t)
			local ret, err = conn:write(t);
			if not ret then
				client.log("debug", "Error writing to connection: %s", err);
				return false, err;
			end
			return true;
		end
		client.log("debug", "Opening stream...");
		client:open_stream();
	end

	function listeners.onincoming(conn, data) --luacheck: ignore 212/conn
		local ok, err = client.stream:feed(data);
		if not ok then
			client.log("debug", "Received invalid XML (%s) %d bytes: %q", err, #data, data:sub(1, 300));
			client:close("not-well-formed");
		end
	end

	function listeners.ondisconnect(conn, err) --luacheck: ignore 212/conn
		client.log("info", "Admin client disconnected: %s", err or "connection closed");
		client.conn = nil;
	end

	function listeners.onreadtimeout(conn)
		conn:send(" ");
	end

	client.listeners = listeners;

	return client;
end

return {
	connection = new_connection;
	server = new_server;
	client = new_client;
};