aboutsummaryrefslogtreecommitdiffstats
path: root/plugins/mod_external_services.lua
blob: 51d2d31370f0c42d1657d77660f0ce0a3744cdf4 (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

local dt = require "util.datetime";
local base64 = require "util.encodings".base64;
local hashes = require "util.hashes";
local st = require "util.stanza";
local jid = require "util.jid";

local default_host = module:get_option_string("external_service_host", module.host);
local default_port = module:get_option_number("external_service_port");
local default_secret = module:get_option_string("external_service_secret");
local default_ttl = module:get_option_number("external_service_ttl", 86400);

local configured_services = module:get_option_array("external_services", {});

local access = module:get_option_set("external_service_access", {});

-- filter config into well-defined service records
local function prepare(item)
	if type(item) ~= "table" then
		module:log("error", "Service definition is not a table: %q", item);
		return nil;
	end

	local srv = {
		type = nil;
		transport = nil;
		host = default_host;
		port = default_port;
		username = nil;
		password = nil;
		restricted = nil;
		expires = nil;
	};

	if type(item.type) == "string" then
		srv.type = item.type;
	else
		module:log("error", "Service missing mandatory 'type' field: %q", item);
		return nil;
	end
	if type(item.transport) == "string" then
		srv.transport = item.transport;
	end
	if type(item.host) == "string" then
		srv.host = item.host;
	end
	if type(item.port) == "number" then
		srv.port = item.port;
	end
	if type(item.username) == "string" then
		srv.username = item.username;
	end
	if type(item.password) == "string" then
		srv.password = item.password;
		srv.restricted = true;
	end
	if item.restricted == true then
		srv.restricted = true;
	end
	if type(item.expires) == "number" then
		srv.expires = item.expires;
	elseif type(item.ttl) == "number" then
		srv.expires = os.time() + item.ttl;
	end
	if (item.secret == true and default_secret) or type(item.secret) == "string" then
		local ttl = default_ttl;
		if type(item.ttl) == "number" then
			ttl = item.ttl;
		end
		local expires = os.time() + ttl;
		local secret = item.secret;
		if secret == true then
			secret = default_secret;
		end
		local username;
		if type(item.username) == "string" then
			username = string.format("%d:%s", expires, item.username);
		else
			username = string.format("%d", expires);
		end
		srv.username = username;
		srv.password = base64.encode(hashes.hmac_sha1(secret, srv.username));
		srv.restricted = true;
	end
	return srv;
end

function module.load()
	-- Trigger errors on startup
	local services = configured_services / prepare;
	if #services == 0 then
		module:log("warn", "No services configured or all had errors");
	end
end

local function handle_services(event)
	local origin, stanza = event.origin, event.stanza;
	local action = stanza.tags[1];

	local user_bare = jid.bare(stanza.attr.from);
	local user_host = jid.host(user_bare);
	if not ((access:empty() and origin.type == "c2s") or access:contains(user_bare) or access:contains(user_host)) then
		origin.send(st.error_reply(stanza, "auth", "forbidden"));
		return true;
	end

	local reply = st.reply(stanza):tag("services", { xmlns = action.attr.xmlns });
	local services = configured_services / prepare;

	local requested_type = action.attr.type;
	if requested_type then
		services:filter(function(item)
			return item.type == requested_type;
		end);
	end

	module:fire_event("external_service/services", {
			origin = origin;
			stanza = stanza;
			reply = reply;
			requested_type = requested_type;
			services = services;
		});

	for _, srv in ipairs(services) do
		reply:tag("service", {
				type = srv.type;
				transport = srv.transport;
				host = srv.host;
				port = srv.port and string.format("%d", srv.port) or nil;
				username = srv.username;
				password = srv.password;
				expires = srv.expires and dt.datetime(srv.expires) or nil;
				restricted = srv.restricted and "1" or nil;
			}):up();
	end

	origin.send(reply);
	return true;
end

local function handle_credentials(event)
	local origin, stanza = event.origin, event.stanza;
	local action = stanza.tags[1];

	if origin.type ~= "c2s" then
		origin.send(st.error_reply(stanza, "auth", "forbidden"));
		return true;
	end

	local reply = st.reply(stanza):tag("credentials", { xmlns = action.attr.xmlns });
	local services = configured_services / prepare;
	services:filter(function (item)
		return item.restricted;
	end)

	local requested_credentials = {};
	for service in action:childtags("service") do
		table.insert(requested_credentials, {
				type = service.attr.type;
				host = service.attr.host;
				port = tonumber(service.attr.port);
			});
	end

	module:fire_event("external_service/credentials", {
			origin = origin;
			stanza = stanza;
			reply = reply;
			requested_credentials = requested_credentials;
			services = services;
		});

	for req_srv in action:childtags("service") do
		for _, srv in ipairs(services) do
			if srv.type == req_srv.attr.type and srv.host == req_srv.attr.host
				and not req_srv.attr.port or srv.port == tonumber(req_srv.attr.port) then
				reply:tag("service", {
						type = srv.type;
						transport = srv.transport;
						host = srv.host;
						port = srv.port and string.format("%d", srv.port) or nil;
						username = srv.username;
						password = srv.password;
						expires = srv.expires and dt.datetime(srv.expires) or nil;
						restricted = srv.restricted and "1" or nil;
					}):up();
			end
		end
	end

	origin.send(reply);
	return true;
end

-- XEP-0215 v0.7
module:add_feature("urn:xmpp:extdisco:2");
module:hook("iq-get/host/urn:xmpp:extdisco:2:services", handle_services);
module:hook("iq-get/host/urn:xmpp:extdisco:2:credentials", handle_credentials);

-- COMPAT XEP-0215 v0.6
-- Those still on the old version gets to deal with undefined attributes until they upgrade.
module:add_feature("urn:xmpp:extdisco:1");
module:hook("iq-get/host/urn:xmpp:extdisco:1:services", handle_services);
module:hook("iq-get/host/urn:xmpp:extdisco:1:credentials", handle_credentials);