1// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
2//
3// This Source Code Form is subject to the terms of the Mozilla Public
4// License, v. 2.0. If a copy of the MPL was not distributed with this
5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
6
7use std::convert::TryFrom;
8
9use disco::{Feature, Identity, Disco};
10use data_forms::DataForm;
11use hashes::{Hash, Algo};
12
13use minidom::Element;
14use error::Error;
15use ns;
16use base64;
17
18use sha_1::Sha1;
19use sha2::{Sha256, Sha512};
20use sha3::{Sha3_256, Sha3_512};
21use blake2::Blake2b;
22use digest::{Digest, VariableOutput};
23
24#[derive(Debug, Clone)]
25pub struct Caps {
26 pub ext: Option<String>,
27 pub node: String,
28 pub hash: Hash,
29}
30
31impl TryFrom<Element> for Caps {
32 type Error = Error;
33
34 fn try_from(elem: Element) -> Result<Caps, Error> {
35 if !elem.is("c", ns::CAPS) {
36 return Err(Error::ParseError("This is not a caps element."));
37 }
38 for _ in elem.children() {
39 return Err(Error::ParseError("Unknown child in caps element."));
40 }
41 let hash = get_attr!(elem, "hash", required);
42 let ver: String = get_attr!(elem, "ver", required);
43 let hash = Hash {
44 algo: hash,
45 hash: base64::decode(&ver)?,
46 };
47 Ok(Caps {
48 ext: get_attr!(elem, "ext", optional),
49 node: get_attr!(elem, "node", required),
50 hash: hash,
51 })
52 }
53}
54
55impl From<Caps> for Element {
56 fn from(caps: Caps) -> Element {
57 Element::builder("c")
58 .ns(ns::CAPS)
59 .attr("ext", caps.ext)
60 .attr("hash", caps.hash.algo)
61 .attr("node", caps.node)
62 .attr("ver", base64::encode(&caps.hash.hash))
63 .build()
64 }
65}
66
67fn compute_item(field: &str) -> Vec<u8> {
68 let mut bytes = field.as_bytes().to_vec();
69 bytes.push(b'<');
70 bytes
71}
72
73fn compute_items<T, F: Fn(&T) -> Vec<u8>>(things: &[T], encode: F) -> Vec<u8> {
74 let mut string: Vec<u8> = vec!();
75 let mut accumulator: Vec<Vec<u8>> = vec!();
76 for thing in things {
77 let bytes = encode(thing);
78 accumulator.push(bytes);
79 }
80 // This works using the expected i;octet collation.
81 accumulator.sort();
82 for mut bytes in accumulator {
83 string.append(&mut bytes);
84 }
85 string
86}
87
88fn compute_features(features: &[Feature]) -> Vec<u8> {
89 compute_items(features, |feature| compute_item(&feature.var))
90}
91
92fn compute_identities(identities: &[Identity]) -> Vec<u8> {
93 compute_items(identities, |identity| {
94 let string = format!("{}/{}/{}/{}", identity.category, identity.type_, identity.xml_lang, match identity.name { Some(ref name) => name.clone(), None => String::new() });
95 let bytes = string.as_bytes();
96 let mut vec = Vec::with_capacity(bytes.len());
97 vec.extend_from_slice(bytes);
98 vec.push(b'<');
99 vec
100 })
101}
102
103fn compute_extensions(extensions: &[DataForm]) -> Vec<u8> {
104 compute_items(extensions, |extension| {
105 let mut bytes = vec!();
106 // TODO: maybe handle the error case?
107 if let Some(ref form_type) = extension.form_type {
108 bytes.extend_from_slice(form_type.as_bytes());
109 }
110 bytes.push(b'<');
111 for field in extension.fields.clone() {
112 if field.var == "FORM_TYPE" {
113 continue;
114 }
115 bytes.append(&mut compute_item(&field.var));
116 bytes.append(&mut compute_items(&field.values,
117 |value| compute_item(value)));
118 }
119 bytes
120 })
121}
122
123pub fn compute_disco(disco: &Disco) -> Vec<u8> {
124 let identities_string = compute_identities(&disco.identities);
125 let features_string = compute_features(&disco.features);
126 let extensions_string = compute_extensions(&disco.extensions);
127
128 let mut final_string = vec!();
129 final_string.extend(identities_string);
130 final_string.extend(features_string);
131 final_string.extend(extensions_string);
132 final_string
133}
134
135fn get_hash_vec(hash: &[u8]) -> Vec<u8> {
136 let mut vec = Vec::with_capacity(hash.len());
137 vec.extend_from_slice(hash);
138 vec
139}
140
141pub fn hash_caps(data: &[u8], algo: Algo) -> Result<Hash, String> {
142 Ok(Hash {
143 hash: match algo {
144 Algo::Sha_1 => {
145 let mut hasher = Sha1::default();
146 hasher.input(data);
147 let hash = hasher.result();
148 get_hash_vec(hash.as_slice())
149 },
150 Algo::Sha_256 => {
151 let mut hasher = Sha256::default();
152 hasher.input(data);
153 let hash = hasher.result();
154 get_hash_vec(hash.as_slice())
155 },
156 Algo::Sha_512 => {
157 let mut hasher = Sha512::default();
158 hasher.input(data);
159 let hash = hasher.result();
160 get_hash_vec(hash.as_slice())
161 },
162 Algo::Sha3_256 => {
163 let mut hasher = Sha3_256::default();
164 hasher.input(data);
165 let hash = hasher.result();
166 get_hash_vec(hash.as_slice())
167 },
168 Algo::Sha3_512 => {
169 let mut hasher = Sha3_512::default();
170 hasher.input(data);
171 let hash = hasher.result();
172 get_hash_vec(hash.as_slice())
173 },
174 Algo::Blake2b_256 => {
175 let mut hasher = Blake2b::default();
176 hasher.input(data);
177 let mut buf: [u8; 32] = [0; 32];
178 let hash = hasher.variable_result(&mut buf).unwrap();
179 get_hash_vec(hash)
180 },
181 Algo::Blake2b_512 => {
182 let mut hasher = Blake2b::default();
183 hasher.input(data);
184 let mut buf: [u8; 64] = [0; 64];
185 let hash = hasher.variable_result(&mut buf).unwrap();
186 get_hash_vec(hash)
187 },
188 Algo::Unknown(algo) => return Err(format!("Unknown algorithm: {}.", algo)),
189 },
190 algo: algo,
191 })
192}
193
194#[cfg(test)]
195mod tests {
196 use super::*;
197 use caps;
198 use base64;
199
200 #[test]
201 fn test_parse() {
202 let elem: Element = "<c xmlns='http://jabber.org/protocol/caps' hash='sha-256' node='coucou' ver='K1Njy3HZBThlo4moOD5gBGhn0U0oK7/CbfLlIUDi6o4='/>".parse().unwrap();
203 let caps = Caps::try_from(elem).unwrap();
204 assert_eq!(caps.node, String::from("coucou"));
205 assert_eq!(caps.hash.algo, Algo::Sha_256);
206 assert_eq!(caps.hash.hash, base64::decode("K1Njy3HZBThlo4moOD5gBGhn0U0oK7/CbfLlIUDi6o4=").unwrap());
207 }
208
209 #[test]
210 fn test_invalid_child() {
211 let elem: Element = "<c xmlns='http://jabber.org/protocol/caps'><hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>K1Njy3HZBThlo4moOD5gBGhn0U0oK7/CbfLlIUDi6o4=</hash></c>".parse().unwrap();
212 let error = Caps::try_from(elem).unwrap_err();
213 let message = match error {
214 Error::ParseError(string) => string,
215 _ => panic!(),
216 };
217 assert_eq!(message, "Unknown child in caps element.");
218 }
219
220 #[test]
221 fn test_simple() {
222 let elem: Element = "<query xmlns='http://jabber.org/protocol/disco#info'><identity category='client' type='pc'/><feature var='http://jabber.org/protocol/disco#info'/></query>".parse().unwrap();
223 let disco = Disco::try_from(elem).unwrap();
224 let caps = caps::compute_disco(&disco);
225 assert_eq!(caps.len(), 50);
226 }
227
228 #[test]
229 fn test_xep_5_2() {
230 let elem: Element = r#"
231<query xmlns='http://jabber.org/protocol/disco#info'
232 node='http://psi-im.org#q07IKJEyjvHSyhy//CH0CxmKi8w='>
233 <identity category='client' name='Exodus 0.9.1' type='pc'/>
234 <feature var='http://jabber.org/protocol/caps'/>
235 <feature var='http://jabber.org/protocol/disco#info'/>
236 <feature var='http://jabber.org/protocol/disco#items'/>
237 <feature var='http://jabber.org/protocol/muc'/>
238</query>
239"#.parse().unwrap();
240
241 let data = b"client/pc//Exodus 0.9.1<http://jabber.org/protocol/caps<http://jabber.org/protocol/disco#info<http://jabber.org/protocol/disco#items<http://jabber.org/protocol/muc<";
242 let mut expected = Vec::with_capacity(data.len());
243 expected.extend_from_slice(data);
244 let disco = Disco::try_from(elem).unwrap();
245 let caps = caps::compute_disco(&disco);
246 assert_eq!(caps, expected);
247
248 let sha_1 = caps::hash_caps(&caps, Algo::Sha_1).unwrap();
249 assert_eq!(sha_1.hash, base64::decode("QgayPKawpkPSDYmwT/WM94uAlu0=").unwrap());
250 }
251
252 #[test]
253 fn test_xep_5_3() {
254 let elem: Element = r#"
255<query xmlns='http://jabber.org/protocol/disco#info'
256 node='http://psi-im.org#q07IKJEyjvHSyhy//CH0CxmKi8w='>
257 <identity xml:lang='en' category='client' name='Psi 0.11' type='pc'/>
258 <identity xml:lang='el' category='client' name='Ψ 0.11' type='pc'/>
259 <feature var='http://jabber.org/protocol/caps'/>
260 <feature var='http://jabber.org/protocol/disco#info'/>
261 <feature var='http://jabber.org/protocol/disco#items'/>
262 <feature var='http://jabber.org/protocol/muc'/>
263 <x xmlns='jabber:x:data' type='result'>
264 <field var='FORM_TYPE' type='hidden'>
265 <value>urn:xmpp:dataforms:softwareinfo</value>
266 </field>
267 <field var='ip_version'>
268 <value>ipv4</value>
269 <value>ipv6</value>
270 </field>
271 <field var='os'>
272 <value>Mac</value>
273 </field>
274 <field var='os_version'>
275 <value>10.5.1</value>
276 </field>
277 <field var='software'>
278 <value>Psi</value>
279 </field>
280 <field var='software_version'>
281 <value>0.11</value>
282 </field>
283 </x>
284</query>
285"#.parse().unwrap();
286 let data = b"client/pc/el/\xce\xa8 0.11<client/pc/en/Psi 0.11<http://jabber.org/protocol/caps<http://jabber.org/protocol/disco#info<http://jabber.org/protocol/disco#items<http://jabber.org/protocol/muc<urn:xmpp:dataforms:softwareinfo<ip_version<ipv4<ipv6<os<Mac<os_version<10.5.1<software<Psi<software_version<0.11<";
287 let mut expected = Vec::with_capacity(data.len());
288 expected.extend_from_slice(data);
289 let disco = Disco::try_from(elem).unwrap();
290 let caps = caps::compute_disco(&disco);
291 assert_eq!(caps, expected);
292
293 let sha_1 = caps::hash_caps(&caps, Algo::Sha_1).unwrap();
294 assert_eq!(sha_1.hash, base64::decode("q07IKJEyjvHSyhy//CH0CxmKi8w=").unwrap());
295 }
296}