-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
module:set_global(); -- Global module
local hosts = _G.hosts;
local new_xmpp_stream = require "util.xmppstream".new;
local sm = require "core.sessionmanager";
local sm_destroy_session = sm.destroy_session;
local new_uuid = require "util.uuid".generate;
local fire_event = prosody.events.fire_event;
local core_process_stanza = core_process_stanza;
local st = require "util.stanza";
local logger = require "util.logger";
local log = logger.init("mod_bosh");
local xmlns_streams = "http://etherx.jabber.org/streams";
local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
local stream_callbacks = {
stream_ns = xmlns_bosh, stream_tag = "body", default_ns = "jabber:client" };
local BOSH_DEFAULT_HOLD = module:get_option_number("bosh_default_hold", 1);
local BOSH_DEFAULT_INACTIVITY = module:get_option_number("bosh_max_inactivity", 60);
local BOSH_DEFAULT_POLLING = module:get_option_number("bosh_max_polling", 5);
local BOSH_DEFAULT_REQUESTS = module:get_option_number("bosh_max_requests", 2);
local consider_bosh_secure = module:get_option_boolean("consider_bosh_secure");
local auto_cork = module:get_option_boolean("bosh_auto_cork", false);
local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
local cross_domain = module:get_option("cross_domain_bosh", false);
if cross_domain then
default_headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS";
default_headers["Access-Control-Allow-Headers"] = "Content-Type";
default_headers["Access-Control-Max-Age"] = "7200";
if cross_domain == true then
default_headers["Access-Control-Allow-Origin"] = "*";
elseif type(cross_domain) == "table" then
cross_domain = table.concat(cross_domain, ", ");
end
if type(cross_domain) == "string" then
default_headers["Access-Control-Allow-Origin"] = cross_domain;
end
end
local trusted_proxies = module:get_option_set("trusted_proxies", {"127.0.0.1"})._items;
local function get_ip_from_request(request)
local ip = request.conn:ip();
local forwarded_for = request.headers["x-forwarded-for"];
if forwarded_for then
forwarded_for = forwarded_for..", "..ip;
for forwarded_ip in forwarded_for:gmatch("[^%s,]+") do
if not trusted_proxies[forwarded_ip] then
ip = forwarded_ip;
end
end
end
return ip;
end
local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
local os_time = os.time;
local sessions = {};
local inactive_sessions = {}; -- Sessions which have no open requests
-- Used to respond to idle sessions (those with waiting requests)
local waiting_requests = {};
function on_destroy_request(request)
log("debug", "Request destroyed: %s", tostring(request));
waiting_requests[request] = nil;
local session = sessions[request.context.sid];
if session then
local requests = session.requests;
for i, r in ipairs(requests) do
if r == request then
t_remove(requests, i);
break;
end
end
-- If this session now has no requests open, mark it as inactive
local max_inactive = session.bosh_max_inactive;
if max_inactive and #requests == 0 then
inactive_sessions[session] = os_time() + max_inactive;
(session.log or log)("debug", "BOSH session marked as inactive (for %ds)", max_inactive);
end
end
end
local function handle_GET(request)
return [[
It works! Now point your BOSH client to this URL to connect to Prosody.
For more information see Prosody: Setting up BOSH.
]];
end
function handle_OPTIONS(request)
local headers = {};
for k,v in pairs(default_headers) do headers[k] = v; end
headers["Content-Type"] = nil;
return { headers = headers, body = "" };
end
function handle_POST(event)
log("debug", "Handling new request %s: %s\n----------", tostring(event.request), tostring(event.request.body));
local request, response = event.request, event.response;
response.on_destroy = on_destroy_request;
local body = request.body;
local context = { request = request, response = response, notopen = true };
local stream = new_xmpp_stream(context, stream_callbacks);
response.context = context;
-- stream:feed() calls the stream_callbacks, so all stanzas in
-- the body are processed in this next line before it returns.
-- In particular, the streamopened() stream callback is where
-- much of the session logic happens, because it's where we first
-- get to see the 'sid' of this request.
stream:feed(body);
-- Stanzas (if any) in the request have now been processed, and
-- we take care of the high-level BOSH logic here, including
-- giving a response or putting the request "on hold".
local session = sessions[context.sid];
if session then
-- Session was marked as inactive, since we have
-- a request open now, unmark it
if inactive_sessions[session] and #session.requests > 0 then
inactive_sessions[session] = nil;
end
local r = session.requests;
log("debug", "Session %s has %d out of %d requests open", context.sid, #r, session.bosh_hold);
log("debug", "and there are %d things in the send_buffer:", #session.send_buffer);
for i, thing in ipairs(session.send_buffer) do
log("debug", " %s", tostring(thing));
end
if #r > session.bosh_hold then
-- We are holding too many requests, send what's in the buffer,
log("debug", "We are holding too many requests, so...");
if #session.send_buffer > 0 then
log("debug", "...sending what is in the buffer")
session.send(t_concat(session.send_buffer));
session.send_buffer = {};
else
-- or an empty response
log("debug", "...sending an empty response");
session.send("");
end
elseif #session.send_buffer > 0 then
log("debug", "Session has data in the send buffer, will send now..");
local resp = t_concat(session.send_buffer);
session.send_buffer = {};
session.send(resp);
end
if not response.finished then
-- We're keeping this request open, to respond later
log("debug", "Have nothing to say, so leaving request unanswered for now");
if session.bosh_wait then
waiting_requests[response] = os_time() + session.bosh_wait;
end
end
if session.bosh_terminate then
session.log("debug", "Closing session with %d requests open", #session.requests);
session:close();
return nil;
else
return true; -- Inform http server we shall reply later
end
end
end
local function bosh_reset_stream(session) session.notopen = true; end
local stream_xmlns_attr = { xmlns = "urn:ietf:params:xml:ns:xmpp-streams" };
local function bosh_close_stream(session, reason)
(session.log or log)("info", "BOSH client disconnected");
local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
["xmlns:stream"] = xmlns_streams });
if reason then
close_reply.attr.condition = "remote-stream-error";
if type(reason) == "string" then -- assume stream error
close_reply:tag("stream:error")
:tag(reason, {xmlns = xmlns_xmpp_streams});
elseif type(reason) == "table" then
if reason.condition then
close_reply:tag("stream:error")
:tag(reason.condition, stream_xmlns_attr):up();
if reason.text then
close_reply:tag("text", stream_xmlns_attr):text(reason.text):up();
end
if reason.extra then
close_reply:add_child(reason.extra);
end
elseif reason.name then -- a stanza
close_reply = reason;
end
end
log("info", "Disconnecting client, is: %s", tostring(close_reply));
end
local response_body = tostring(close_reply);
for _, held_request in ipairs(session.requests) do
held_request.headers = default_headers;
held_request:send(response_body);
end
sessions[session.sid] = nil;
inactive_sessions[session] = nil;
sm_destroy_session(session);
end
-- Handle the tag in the request payload.
function stream_callbacks.streamopened(context, attr)
local request, response = context.request, context.response;
local sid = attr.sid;
log("debug", "BOSH body open (sid: %s)", sid or "");
if not sid then
-- New session request
context.notopen = nil; -- Signals that we accept this opening tag
-- TODO: Sanity checks here (rid, to, known host, etc.)
if not hosts[attr.to] then
-- Unknown host
log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
["xmlns:stream"] = xmlns_streams, condition = "host-unknown" });
response:send(tostring(close_reply));
return;
end
-- New session
sid = new_uuid();
local session = {
type = "c2s_unauthed", conn = {}, sid = sid, rid = tonumber(attr.rid), host = attr.to,
bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream,
close = bosh_close_stream, dispatch_stanza = core_process_stanza,
log = logger.init("bosh"..sid), secure = consider_bosh_secure or request.secure,
ip = get_ip_from_request(request);
};
sessions[sid] = session;
session.log("debug", "BOSH session created for request from %s", session.ip);
log("info", "New BOSH session, assigned it sid '%s'", sid);
local r, send_buffer = session.requests, session.send_buffer;
function session.send(s)
-- We need to ensure that outgoing stanzas have the jabber:client xmlns
if s.attr and not s.attr.xmlns then
s = st.clone(s);
s.attr.xmlns = "jabber:client";
end
--log("debug", "Sending BOSH data: %s", tostring(s));
local oldest_request = r[1];
if oldest_request and (not(auto_cork) or waiting_requests[oldest_request]) then
log("debug", "We have an open request, so sending on that");
oldest_request.headers = default_headers;
oldest_request:send(t_concat({
"",
tostring(s),
""
}));
elseif s ~= "" then
log("debug", "Saved to send buffer because there are %d open requests", #r);
-- Hmm, no requests are open :(
t_insert(session.send_buffer, tostring(s));
log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
end
return true;
end
-- Send creation response
local features = st.stanza("stream:features");
hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
fire_event("stream-features", session, features);
--xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
local body = st.stanza("body", { xmlns = xmlns_bosh,
wait = attr.wait,
inactivity = tostring(BOSH_DEFAULT_INACTIVITY),
polling = tostring(BOSH_DEFAULT_POLLING),
requests = tostring(BOSH_DEFAULT_REQUESTS),
hold = tostring(session.bosh_hold),
sid = sid, authid = sid,
ver = '1.6', from = session.host,
secure = 'true', ["xmpp:version"] = "1.0",
["xmlns:xmpp"] = "urn:xmpp:xbosh",
["xmlns:stream"] = "http://etherx.jabber.org/streams"
}):add_child(features);
response.headers = default_headers;
response:send(tostring(body));
request.sid = sid;
return;
end
local session = sessions[sid];
if not session then
-- Unknown sid
log("info", "Client tried to use sid '%s' which we don't know about", sid);
response.headers = default_headers;
response:send(tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })));
context.notopen = nil;
return;
end
if session.rid then
local rid = tonumber(attr.rid);
local diff = rid - session.rid;
if diff > 1 then
session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
elseif diff <= 0 then
-- Repeated, ignore
session.log("debug", "rid repeated (on request %s), ignoring: %s (diff %d)", request.id, session.rid, diff);
context.notopen = nil;
context.ignore = true;
context.sid = sid;
t_insert(session.requests, response);
return;
end
session.rid = rid;
end
if attr.type == "terminate" then
-- Client wants to end this session, which we'll do
-- after processing any stanzas in this request
session.bosh_terminate = true;
end
context.notopen = nil; -- Signals that we accept this opening tag
t_insert(session.requests, response);
context.sid = sid;
if session.notopen then
local features = st.stanza("stream:features");
hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
fire_event("stream-features", session, features);
session.send(features);
session.notopen = nil;
end
end
function stream_callbacks.handlestanza(context, stanza)
if context.ignore then return; end
log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
local session = sessions[context.sid];
if session then
if stanza.attr.xmlns == xmlns_bosh then
stanza.attr.xmlns = nil;
end
core_process_stanza(session, stanza);
end
end
function stream_callbacks.error(context, error)
log("debug", "Error parsing BOSH request payload; %s", error);
if not context.sid then
local response = context.response;
response.headers = default_headers;
response.status_code = 400;
response:send();
return;
end
local session = sessions[context.sid];
if error == "stream-error" then -- Remote stream error, we close normally
session:close();
else
session:close({ condition = "bad-format", text = "Error processing stream" });
end
end
local dead_sessions = {};
function on_timer()
-- log("debug", "Checking for requests soon to timeout...");
-- Identify requests timing out within the next few seconds
local now = os_time() + 3;
for request, reply_before in pairs(waiting_requests) do
if reply_before <= now then
log("debug", "%s was soon to timeout (at %d, now %d), sending empty response", tostring(request), reply_before, now);
-- Send empty response to let the
-- client know we're still here
if request.conn then
sessions[request.context.sid].send("");
end
end
end
now = now - 3;
local n_dead_sessions = 0;
for session, close_after in pairs(inactive_sessions) do
if close_after < now then
(session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
sessions[session.sid] = nil;
inactive_sessions[session] = nil;
n_dead_sessions = n_dead_sessions + 1;
dead_sessions[n_dead_sessions] = session;
end
end
for i=1,n_dead_sessions do
local session = dead_sessions[i];
dead_sessions[i] = nil;
sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
end
return 1;
end
module:add_timer(1, on_timer);
function module.add_host(module)
module:depends("http");
module:provides("http", {
default_path = "/http-bind";
route = {
["GET"] = handle_GET;
["GET /"] = handle_GET;
["OPTIONS"] = handle_OPTIONS;
["OPTIONS /"] = handle_OPTIONS;
["POST"] = handle_POST;
["POST /"] = handle_POST;
};
});
end