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
|
-- 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.
--
local lxp = require "lxp";
local st = require "util.stanza";
local stanza_mt = st.stanza_mt;
local tostring = tostring;
local t_insert = table.insert;
local t_concat = table.concat;
local t_remove = table.remove;
local setmetatable = setmetatable;
local default_log = require "util.logger".init("xmppstream");
-- COMPAT: w/LuaExpat 1.1.0
local lxp_supports_doctype = pcall(lxp.new, { StartDoctypeDecl = false });
if not lxp_supports_doctype then
default_log("warn", "The version of LuaExpat on your system leaves Prosody "
.."vulnerable to denial-of-service attacks. You should upgrade to "
.."LuaExpat 1.1.1 or higher as soon as possible. See "
.."http://prosody.im/doc/depends#luaexpat for more information.");
end
local error = error;
module "xmppstream"
local new_parser = lxp.new;
local ns_prefixes = {
["http://www.w3.org/XML/1998/namespace"] = "xml";
};
local xmlns_streams = "http://etherx.jabber.org/streams";
local ns_separator = "\1";
local ns_pattern = "^([^"..ns_separator.."]*)"..ns_separator.."?(.*)$";
_M.ns_separator = ns_separator;
_M.ns_pattern = ns_pattern;
function new_sax_handlers(session, stream_callbacks)
local xml_handlers = {};
local log = session.log or default_log;
local cb_streamopened = stream_callbacks.streamopened;
local cb_streamclosed = stream_callbacks.streamclosed;
local cb_error = stream_callbacks.error or function(session, e) error("XML stream error: "..tostring(e)); end;
local cb_handlestanza = stream_callbacks.handlestanza;
local stream_ns = stream_callbacks.stream_ns or xmlns_streams;
local stream_tag = stream_callbacks.stream_tag or "stream";
if stream_ns ~= "" then
stream_tag = stream_ns..ns_separator..stream_tag;
end
local stream_error_tag = stream_ns..ns_separator..(stream_callbacks.error_tag or "error");
local stream_default_ns = stream_callbacks.default_ns;
local stack = {};
local chardata, stanza = {};
local non_streamns_depth = 0;
function xml_handlers:StartElement(tagname, attr)
if stanza and #chardata > 0 then
-- We have some character data in the buffer
t_insert(stanza, t_concat(chardata));
chardata = {};
end
local curr_ns,name = tagname:match(ns_pattern);
if name == "" then
curr_ns, name = "", curr_ns;
end
if curr_ns ~= stream_default_ns or non_streamns_depth > 0 then
attr.xmlns = curr_ns;
non_streamns_depth = non_streamns_depth + 1;
end
-- FIXME !!!!!
for i=1,#attr do
local k = attr[i];
attr[i] = nil;
local ns, nm = k:match(ns_pattern);
if nm ~= "" then
ns = ns_prefixes[ns];
if ns then
attr[ns..":"..nm] = attr[k];
attr[k] = nil;
end
end
end
if not stanza then --if we are not currently inside a stanza
if session.notopen then
if tagname == stream_tag then
non_streamns_depth = 0;
if cb_streamopened then
cb_streamopened(session, attr);
end
else
-- Garbage before stream?
cb_error(session, "no-stream");
end
return;
end
if curr_ns == "jabber:client" and name ~= "iq" and name ~= "presence" and name ~= "message" then
cb_error(session, "invalid-top-level-element");
end
stanza = setmetatable({ name = name, attr = attr, tags = {} }, stanza_mt);
else -- we are inside a stanza, so add a tag
t_insert(stack, stanza);
local oldstanza = stanza;
stanza = setmetatable({ name = name, attr = attr, tags = {} }, stanza_mt);
t_insert(oldstanza, stanza);
t_insert(oldstanza.tags, stanza);
end
end
function xml_handlers:CharacterData(data)
if stanza then
t_insert(chardata, data);
end
end
function xml_handlers:EndElement(tagname)
if non_streamns_depth > 0 then
non_streamns_depth = non_streamns_depth - 1;
end
if stanza then
if #chardata > 0 then
-- We have some character data in the buffer
t_insert(stanza, t_concat(chardata));
chardata = {};
end
-- Complete stanza
if #stack == 0 then
if tagname ~= stream_error_tag then
cb_handlestanza(session, stanza);
else
cb_error(session, "stream-error", stanza);
end
stanza = nil;
else
stanza = t_remove(stack);
end
else
if tagname == stream_tag then
if cb_streamclosed then
cb_streamclosed(session);
end
else
local curr_ns,name = tagname:match(ns_pattern);
if name == "" then
curr_ns, name = "", curr_ns;
end
cb_error(session, "parse-error", "unexpected-element-close", name);
end
stanza, chardata = nil, {};
stack = {};
end
end
local function restricted_handler()
cb_error(session, "parse-error", "restricted-xml", "Restricted XML, see RFC 6120 section 11.1.");
end
if lxp_supports_doctype then
xml_handlers.StartDoctypeDecl = restricted_handler;
end
xml_handlers.Comment = restricted_handler;
xml_handlers.ProcessingInstruction = restricted_handler;
local function reset()
stanza, chardata = nil, {};
stack = {};
end
local function set_session(stream, new_session)
session = new_session;
log = new_session.log or default_log;
end
return xml_handlers, { reset = reset, set_session = set_session };
end
function new(session, stream_callbacks)
local handlers, meta = new_sax_handlers(session, stream_callbacks);
local parser = new_parser(handlers, ns_separator);
local parse = parser.parse;
return {
reset = function ()
parser = new_parser(handlers, ns_separator);
parse = parser.parse;
meta.reset();
end,
feed = function (self, data)
return parse(parser, data);
end,
set_session = meta.set_session;
};
end
return _M;
|