aboutsummaryrefslogtreecommitdiffstats
path: root/core/stanza_router.lua
blob: 2399c25f2705814206eafc49ef99a4d0c8111864 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265

-- The code in this file should be self-explanatory, though the logic is horrible
-- for more info on that, see doc/stanza_routing.txt, which attempts to condense
-- the rules from the RFCs (mainly 3921)

require "core.servermanager"

local log = require "util.logger".init("stanzarouter")

local st = require "util.stanza";
local send = require "core.sessionmanager".send_to_session;
local send_s2s = require "core.s2smanager".send_to_host;
local user_exists = require "core.usermanager".user_exists;

local s2s_verify_dialback = require "core.s2smanager".verify_dialback;
local s2s_make_authenticated = require "core.s2smanager".make_authenticated;
local format = string.format;
local tostring = tostring;

local jid_split = require "util.jid".split;
local print = print;

function core_process_stanza(origin, stanza)
	log("debug", "Received: "..tostring(stanza))
	-- TODO verify validity of stanza (as well as JID validity)
	if stanza.name == "iq" and not(#stanza.tags == 1 and stanza.tags[1].attr.xmlns) then
		if stanza.attr.type == "set" or stanza.attr.type == "get" then
			error("Invalid IQ");
		elseif #stanza.tags > 1 or not(stanza.attr.type == "error" or stanza.attr.type == "result") then
			error("Invalid IQ");
		end
	end

	if origin.type == "c2s" and not origin.full_jid
		and not(stanza.name == "iq" and stanza.tags[1].name == "bind"
				and stanza.tags[1].attr.xmlns == "urn:ietf:params:xml:ns:xmpp-bind") then
		error("Client MUST bind resource after auth");
	end

	local to = stanza.attr.to;
	-- TODO also, stazas should be returned to their original state before the function ends
	if origin.type == "c2s" then
		stanza.attr.from = origin.full_jid; -- quick fix to prevent impersonation (FIXME this would be incorrect when the origin is not c2s)
	end
	
	if not to then
			core_handle_stanza(origin, stanza);
	elseif hosts[to] and hosts[to].type == "local" then
		core_handle_stanza(origin, stanza);
	elseif stanza.name == "iq" and not select(3, jid_split(to)) then
		core_handle_stanza(origin, stanza);
	elseif origin.type == "c2s" then
		core_route_stanza(origin, stanza);
	elseif origin.type == "s2sin" then
		core_deliver_stanza(origin, stanza);
	end
end

-- This function handles stanzas which are not routed any further,
-- that is, they are handled by this server
function core_handle_stanza(origin, stanza)
	-- Handlers
	if origin.type == "c2s" or origin.type == "c2s_unauthed" then
		local session = origin;
		
		if stanza.name == "presence" and origin.roster then
			if stanza.attr.type == nil or stanza.attr.type == "available" or stanza.attr.type == "unavailable" then
				for jid in pairs(origin.roster) do -- broadcast to all interested contacts
					local subscription = origin.roster[jid].subscription;
					if subscription == "both" or subscription == "from" then
						stanza.attr.to = jid;
						core_route_stanza(origin, stanza);
					end
				end
				--[[local node, host = jid_split(stanza.attr.from);
				for _, res in pairs(hosts[host].sessions[node].sessions) do -- broadcast to all resources
					if res.full_jid then
						res = user.sessions[k];
						break;
					end
				end]]
				if not origin.presence then -- presence probes on initial presence
					local probe = st.presence({from = origin.full_jid, type = "probe"});
					for jid in pairs(origin.roster) do
						local subscription = origin.roster[jid].subscription;
						if subscription == "both" or subscription == "to" then
							probe.attr.to = jid;
							core_route_stanza(origin, probe);
						end
					end
				end
				origin.presence = stanza;
				stanza.attr.to = nil; -- reset it
			else
				-- TODO error, bad type
			end
		else
			log("debug", "Routing stanza to local");
			handle_stanza(session, stanza);
		end
	elseif origin.type == "s2sin_unauthed" then
		if stanza.attr.xmlns == "jabber:server:dialback" then
			if stanza.name == "verify" then
				-- We are being asked to verify the key, to ensure it was generated by us
				log("debug", "verifying dialback key...");
				local attr = stanza.attr;
				print(tostring(attr.to), tostring(attr.from))
				print(tostring(origin.to_host), tostring(origin.from_host))
				-- FIXME: Grr, ejabberd breaks this one too?? it is black and white in XEP-220 example 34
				--if attr.from ~= origin.to_host then error("invalid-from"); end
				local type = "invalid";
				if s2s_verify_dialback(attr.id, attr.from, attr.to, stanza[1]) then
					type = "valid"
				end
				origin.send(format("<db:verify from='%s' to='%s' id='%s' type='%s'>%s</db:verify>", attr.to, attr.from, attr.id, type, stanza[1]));
			elseif stanza.name == "result" then
				-- We need to check the key with the Authoritative server
				local attr = stanza.attr;
				origin.from_host = attr.from;
				origin.to_host = attr.to;
				origin.dialback_key = stanza[1];
				log("debug", "asking %s if key %s belongs to them", attr.from, stanza[1]);
				send_s2s(attr.to, attr.from, format("<db:verify from='%s' to='%s' id='%s'>%s</db:verify>", attr.to, attr.from, origin.streamid, stanza[1]));
				hosts[attr.from].dialback_verifying = origin;
			end
		end
	elseif origin.type == "s2sout_unauthed" or origin.type == "s2sout" then
		if stanza.attr.xmlns == "jabber:server:dialback" then
			if stanza.name == "result" then
				if stanza.attr.type == "valid" then
					s2s_make_authenticated(origin);
				else
					-- FIXME
					error("dialback failed!");
				end
			elseif stanza.name == "verify" and origin.dialback_verifying then
				local valid;
				local attr = stanza.attr;
				if attr.type == "valid" then
					s2s_make_authenticated(origin.dialback_verifying);
					valid = "valid";
				else
					-- Warn the original connection that is was not verified successfully
					log("warn", "dialback for "..(origin.dialback_verifying.from_host or "(unknown)").." failed");
					valid = "invalid";
				end
				origin.dialback_verifying.send(format("<db:result from='%s' to='%s' id='%s' type='%s'>%s</db:result>", attr.from, attr.to, attr.id, valid, origin.dialback_verifying.dialback_key));
			end
		end
	else
		log("warn", "Unhandled origin: %s", origin.type);
	end
end

-- TODO: Does this function belong here?
function is_authorized_to_see_presence(origin, username, host)
	local roster = datamanager.load(username, host, "roster") or {};
	local item = roster[origin.username.."@"..origin.host];
	return item and (item.subscription == "both" or item.subscription == "from");
end

function core_route_stanza(origin, stanza)
	-- Hooks
	--- ...later
	
	-- Deliver
	local to = stanza.attr.to;
	local node, host, resource = jid_split(to);

	if stanza.name == "presence" and stanza.attr.type == "probe" then resource = nil; end

	local host_session = hosts[host]
	if host_session and host_session.type == "local" then
		-- Local host
		local user = host_session.sessions[node];
		if user then
			local res = user.sessions[resource];
			if not res then
				-- if we get here, resource was not specified or was unavailable
				if stanza.name == "presence" then
					if stanza.attr.type == "probe" then
						if is_authorized_to_see_presence(origin, node, host) then
							for k in pairs(user.sessions) do -- return presence for all resources
								if user.sessions[k].presence then
									local pres = user.sessions[k].presence;
									pres.attr.to = origin.full_jid;
									pres.attr.from = user.sessions[k].full_jid;
									send(origin, pres);
									pres.attr.to = nil;
									pres.attr.from = nil;
								end
							end
						else
							send(origin, st.presence({from = user.."@"..host, to = origin.username.."@"..origin.host, type = "unsubscribed"}));
						end
					else
						for k in pairs(user.sessions) do -- presence broadcast to all user resources
							if user.sessions[k].full_jid then
								stanza.attr.to = user.sessions[k].full_jid;
								send(user.sessions[k], stanza);
							end
						end
					end
				elseif stanza.name == "message" then -- select a resource to recieve message
					for k in pairs(user.sessions) do
						if user.sessions[k].full_jid then
							res = user.sessions[k];
							break;
						end
					end
					-- TODO find resource with greatest priority
					send(res, stanza);
				else
					-- TODO send IQ error
				end
			else
				-- User + resource is online...
				stanza.attr.to = res.full_jid;
				send(res, stanza); -- Yay \o/
			end
		else
			-- user not online
			if user_exists(node, host) then
				if stanza.name == "presence" then
					if stanza.attr.type == "probe" and is_authorized_to_see_presence(origin, node, host) then -- FIXME what to do for not c2s?
						-- TODO send last recieved unavailable presence
					else
						-- TODO send unavailable presence
					end
				elseif stanza.name == "message" then
					-- TODO send message error, or store offline messages
				elseif stanza.name == "iq" then
					-- TODO send IQ error
				end
			else -- user does not exist
				-- TODO we would get here for nodeless JIDs too. Do something fun maybe? Echo service? Let plugins use xmpp:server/resource addresses?
				if stanza.name == "presence" then
					if stanza.attr.type == "probe" then
						send(origin, st.presence({from = user.."@"..host, to = origin.username.."@"..origin.host, type = "unsubscribed"}));
					end
					-- else ignore
				else
					send(origin, st.error_reply(stanza, "cancel", "service-unavailable"));
				end
			end
		end
	else
		-- Remote host
		log("debug", "sending s2s stanza: %s", tostring(stanza));
		stanza.attr.xmlns = "jabber:server";
		send_s2s(origin.host, host, stanza);
	end
	stanza.attr.to = to; -- reset
end

function core_deliver_stanza(origin, stanza)
	local name, attr = stanza.name, stanza.attr;
	if name == "message" then
		
	end
end

function handle_stanza_toremote(stanza)
	log("error", "Stanza bound for remote host, but s2s is not implemented");
end