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 empty = String::new();
95 let string = format!("{}/{}/{}/{}", identity.category, identity.type_, identity.xml_lang, match identity.name { Some(ref name) => name, None => &empty });
96 let bytes = string.as_bytes();
97 let mut vec = Vec::with_capacity(bytes.len());
98 vec.extend_from_slice(bytes);
99 vec.push(b'<');
100 vec
101 })
102}
103
104fn compute_extensions(extensions: &[DataForm]) -> Vec<u8> {
105 compute_items(extensions, |extension| {
106 let mut bytes = vec!();
107 // TODO: maybe handle the error case?
108 if let Some(ref form_type) = extension.form_type {
109 bytes.extend_from_slice(form_type.as_bytes());
110 }
111 bytes.push(b'<');
112 for field in extension.fields.clone() {
113 if field.var == "FORM_TYPE" {
114 continue;
115 }
116 bytes.append(&mut compute_item(&field.var));
117 bytes.append(&mut compute_items(&field.values,
118 |value| compute_item(value)));
119 }
120 bytes
121 })
122}
123
124pub fn compute_disco(disco: &Disco) -> Vec<u8> {
125 let identities_string = compute_identities(&disco.identities);
126 let features_string = compute_features(&disco.features);
127 let extensions_string = compute_extensions(&disco.extensions);
128
129 let mut final_string = vec!();
130 final_string.extend(identities_string);
131 final_string.extend(features_string);
132 final_string.extend(extensions_string);
133 final_string
134}
135
136fn get_hash_vec(hash: &[u8]) -> Vec<u8> {
137 let mut vec = Vec::with_capacity(hash.len());
138 vec.extend_from_slice(hash);
139 vec
140}
141
142pub fn hash_caps(data: &[u8], algo: Algo) -> Result<Hash, String> {
143 Ok(Hash {
144 hash: match algo {
145 Algo::Sha_1 => {
146 let mut hasher = Sha1::default();
147 hasher.input(data);
148 let hash = hasher.result();
149 get_hash_vec(hash.as_slice())
150 },
151 Algo::Sha_256 => {
152 let mut hasher = Sha256::default();
153 hasher.input(data);
154 let hash = hasher.result();
155 get_hash_vec(hash.as_slice())
156 },
157 Algo::Sha_512 => {
158 let mut hasher = Sha512::default();
159 hasher.input(data);
160 let hash = hasher.result();
161 get_hash_vec(hash.as_slice())
162 },
163 Algo::Sha3_256 => {
164 let mut hasher = Sha3_256::default();
165 hasher.input(data);
166 let hash = hasher.result();
167 get_hash_vec(hash.as_slice())
168 },
169 Algo::Sha3_512 => {
170 let mut hasher = Sha3_512::default();
171 hasher.input(data);
172 let hash = hasher.result();
173 get_hash_vec(hash.as_slice())
174 },
175 Algo::Blake2b_256 => {
176 let mut hasher = Blake2b::default();
177 hasher.input(data);
178 let mut buf: [u8; 32] = [0; 32];
179 let hash = hasher.variable_result(&mut buf).unwrap();
180 get_hash_vec(hash)
181 },
182 Algo::Blake2b_512 => {
183 let mut hasher = Blake2b::default();
184 hasher.input(data);
185 let mut buf: [u8; 64] = [0; 64];
186 let hash = hasher.variable_result(&mut buf).unwrap();
187 get_hash_vec(hash)
188 },
189 Algo::Unknown(algo) => return Err(format!("Unknown algorithm: {}.", algo)),
190 },
191 algo: algo,
192 })
193}
194
195pub fn query_caps(caps: Caps) -> Disco {
196 Disco {
197 node: Some(format!("{}#{}", caps.node, base64::encode(&caps.hash.hash))),
198 identities: vec!(),
199 features: vec!(),
200 extensions: vec!(),
201 }
202}
203
204#[cfg(test)]
205mod tests {
206 use super::*;
207 use caps;
208 use base64;
209
210 #[test]
211 fn test_parse() {
212 let elem: Element = "<c xmlns='http://jabber.org/protocol/caps' hash='sha-256' node='coucou' ver='K1Njy3HZBThlo4moOD5gBGhn0U0oK7/CbfLlIUDi6o4='/>".parse().unwrap();
213 let caps = Caps::try_from(elem).unwrap();
214 assert_eq!(caps.node, String::from("coucou"));
215 assert_eq!(caps.hash.algo, Algo::Sha_256);
216 assert_eq!(caps.hash.hash, base64::decode("K1Njy3HZBThlo4moOD5gBGhn0U0oK7/CbfLlIUDi6o4=").unwrap());
217 }
218
219 #[test]
220 fn test_invalid_child() {
221 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();
222 let error = Caps::try_from(elem).unwrap_err();
223 let message = match error {
224 Error::ParseError(string) => string,
225 _ => panic!(),
226 };
227 assert_eq!(message, "Unknown child in caps element.");
228 }
229
230 #[test]
231 fn test_simple() {
232 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();
233 let disco = Disco::try_from(elem).unwrap();
234 let caps = caps::compute_disco(&disco);
235 assert_eq!(caps.len(), 50);
236 }
237
238 #[test]
239 fn test_xep_5_2() {
240 let elem: Element = r#"
241<query xmlns='http://jabber.org/protocol/disco#info'
242 node='http://psi-im.org#q07IKJEyjvHSyhy//CH0CxmKi8w='>
243 <identity category='client' name='Exodus 0.9.1' type='pc'/>
244 <feature var='http://jabber.org/protocol/caps'/>
245 <feature var='http://jabber.org/protocol/disco#info'/>
246 <feature var='http://jabber.org/protocol/disco#items'/>
247 <feature var='http://jabber.org/protocol/muc'/>
248</query>
249"#.parse().unwrap();
250
251 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<";
252 let mut expected = Vec::with_capacity(data.len());
253 expected.extend_from_slice(data);
254 let disco = Disco::try_from(elem).unwrap();
255 let caps = caps::compute_disco(&disco);
256 assert_eq!(caps, expected);
257
258 let sha_1 = caps::hash_caps(&caps, Algo::Sha_1).unwrap();
259 assert_eq!(sha_1.hash, base64::decode("QgayPKawpkPSDYmwT/WM94uAlu0=").unwrap());
260 }
261
262 #[test]
263 fn test_xep_5_3() {
264 let elem: Element = r#"
265<query xmlns='http://jabber.org/protocol/disco#info'
266 node='http://psi-im.org#q07IKJEyjvHSyhy//CH0CxmKi8w='>
267 <identity xml:lang='en' category='client' name='Psi 0.11' type='pc'/>
268 <identity xml:lang='el' category='client' name='Ψ 0.11' type='pc'/>
269 <feature var='http://jabber.org/protocol/caps'/>
270 <feature var='http://jabber.org/protocol/disco#info'/>
271 <feature var='http://jabber.org/protocol/disco#items'/>
272 <feature var='http://jabber.org/protocol/muc'/>
273 <x xmlns='jabber:x:data' type='result'>
274 <field var='FORM_TYPE' type='hidden'>
275 <value>urn:xmpp:dataforms:softwareinfo</value>
276 </field>
277 <field var='ip_version'>
278 <value>ipv4</value>
279 <value>ipv6</value>
280 </field>
281 <field var='os'>
282 <value>Mac</value>
283 </field>
284 <field var='os_version'>
285 <value>10.5.1</value>
286 </field>
287 <field var='software'>
288 <value>Psi</value>
289 </field>
290 <field var='software_version'>
291 <value>0.11</value>
292 </field>
293 </x>
294</query>
295"#.parse().unwrap();
296 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<";
297 let mut expected = Vec::with_capacity(data.len());
298 expected.extend_from_slice(data);
299 let disco = Disco::try_from(elem).unwrap();
300 let caps = caps::compute_disco(&disco);
301 assert_eq!(caps, expected);
302
303 let sha_1 = caps::hash_caps(&caps, Algo::Sha_1).unwrap();
304 assert_eq!(sha_1.hash, base64::decode("q07IKJEyjvHSyhy//CH0CxmKi8w=").unwrap());
305 }
306}