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 crate::util::error::Error;
8use crate::util::helpers::Base64;
9use minidom::IntoAttributeValue;
10use std::num::ParseIntError;
11use std::ops::{Deref, DerefMut};
12use std::str::FromStr;
13
14/// List of the algorithms we support, or Unknown.
15#[allow(non_camel_case_types)]
16#[derive(Debug, Clone, PartialEq, Eq, Hash)]
17pub enum Algo {
18 /// The Secure Hash Algorithm 1, with known vulnerabilities, do not use it.
19 ///
20 /// See https://tools.ietf.org/html/rfc3174
21 Sha_1,
22
23 /// The Secure Hash Algorithm 2, in its 256-bit version.
24 ///
25 /// See https://tools.ietf.org/html/rfc6234
26 Sha_256,
27
28 /// The Secure Hash Algorithm 2, in its 512-bit version.
29 ///
30 /// See https://tools.ietf.org/html/rfc6234
31 Sha_512,
32
33 /// The Secure Hash Algorithm 3, based on Keccak, in its 256-bit version.
34 ///
35 /// See https://keccak.team/files/Keccak-submission-3.pdf
36 Sha3_256,
37
38 /// The Secure Hash Algorithm 3, based on Keccak, in its 512-bit version.
39 ///
40 /// See https://keccak.team/files/Keccak-submission-3.pdf
41 Sha3_512,
42
43 /// The BLAKE2 hash algorithm, for a 256-bit output.
44 ///
45 /// See https://tools.ietf.org/html/rfc7693
46 Blake2b_256,
47
48 /// The BLAKE2 hash algorithm, for a 512-bit output.
49 ///
50 /// See https://tools.ietf.org/html/rfc7693
51 Blake2b_512,
52
53 /// An unknown hash not in this list, you can probably reject it.
54 Unknown(String),
55}
56
57impl FromStr for Algo {
58 type Err = Error;
59
60 fn from_str(s: &str) -> Result<Algo, Error> {
61 Ok(match s {
62 "" => return Err(Error::ParseError("'algo' argument can’t be empty.")),
63
64 "sha-1" => Algo::Sha_1,
65 "sha-256" => Algo::Sha_256,
66 "sha-512" => Algo::Sha_512,
67 "sha3-256" => Algo::Sha3_256,
68 "sha3-512" => Algo::Sha3_512,
69 "blake2b-256" => Algo::Blake2b_256,
70 "blake2b-512" => Algo::Blake2b_512,
71 value => Algo::Unknown(value.to_owned()),
72 })
73 }
74}
75
76impl From<Algo> for String {
77 fn from(algo: Algo) -> String {
78 String::from(match algo {
79 Algo::Sha_1 => "sha-1",
80 Algo::Sha_256 => "sha-256",
81 Algo::Sha_512 => "sha-512",
82 Algo::Sha3_256 => "sha3-256",
83 Algo::Sha3_512 => "sha3-512",
84 Algo::Blake2b_256 => "blake2b-256",
85 Algo::Blake2b_512 => "blake2b-512",
86 Algo::Unknown(text) => return text,
87 })
88 }
89}
90
91impl IntoAttributeValue for Algo {
92 fn into_attribute_value(self) -> Option<String> {
93 Some(String::from(self))
94 }
95}
96
97generate_element!(
98 /// This element represents a hash of some data, defined by the hash
99 /// algorithm used and the computed value.
100 #[derive(PartialEq)]
101 Hash, "hash", HASHES,
102 attributes: [
103 /// The algorithm used to create this hash.
104 algo: Required<Algo> = "algo"
105 ],
106 text: (
107 /// The hash value, as a vector of bytes.
108 hash: Base64<Vec<u8>>
109 )
110);
111
112impl Hash {
113 /// Creates a [Hash] element with the given algo and data.
114 pub fn new(algo: Algo, hash: Vec<u8>) -> Hash {
115 Hash { algo, hash }
116 }
117
118 /// Like [new](#method.new) but takes base64-encoded data before decoding
119 /// it.
120 pub fn from_base64(algo: Algo, hash: &str) -> Result<Hash, Error> {
121 Ok(Hash::new(algo, base64::decode(hash)?))
122 }
123
124 /// Like [new](#method.new) but takes hex-encoded data before decoding it.
125 pub fn from_hex(algo: Algo, hex: &str) -> Result<Hash, ParseIntError> {
126 let mut bytes = vec![];
127 for i in 0..hex.len() / 2 {
128 let byte = u8::from_str_radix(&hex[2 * i..2 * i + 2], 16)?;
129 bytes.push(byte);
130 }
131 Ok(Hash::new(algo, bytes))
132 }
133
134 /// Formats this hash into base64.
135 pub fn to_base64(&self) -> String {
136 base64::encode(&self.hash[..])
137 }
138
139 /// Formats this hash into hexadecimal.
140 pub fn to_hex(&self) -> String {
141 let mut bytes = vec![];
142 for byte in self.hash.iter() {
143 bytes.push(format!("{:02x}", byte));
144 }
145 bytes.join("")
146 }
147
148 /// Formats this hash into colon-separated hexadecimal.
149 pub fn to_colon_hex(&self) -> String {
150 let mut bytes = vec![];
151 for byte in self.hash.iter() {
152 bytes.push(format!("{:02x}", byte));
153 }
154 bytes.join(":")
155 }
156}
157
158/// Helper for parsing and serialising a SHA-1 attribute.
159#[derive(Debug, Clone, PartialEq)]
160pub struct Sha1HexAttribute(Hash);
161
162impl FromStr for Sha1HexAttribute {
163 type Err = ParseIntError;
164
165 fn from_str(hex: &str) -> Result<Self, Self::Err> {
166 let hash = Hash::from_hex(Algo::Sha_1, hex)?;
167 Ok(Sha1HexAttribute(hash))
168 }
169}
170
171impl IntoAttributeValue for Sha1HexAttribute {
172 fn into_attribute_value(self) -> Option<String> {
173 Some(self.to_hex())
174 }
175}
176
177impl DerefMut for Sha1HexAttribute {
178 fn deref_mut(&mut self) -> &mut Self::Target {
179 &mut self.0
180 }
181}
182
183impl Deref for Sha1HexAttribute {
184 type Target = Hash;
185
186 fn deref(&self) -> &Self::Target {
187 &self.0
188 }
189}
190
191#[cfg(test)]
192mod tests {
193 use super::*;
194 use crate::Element;
195 use std::convert::TryFrom;
196
197 #[cfg(target_pointer_width = "32")]
198 #[test]
199 fn test_size() {
200 assert_size!(Algo, 16);
201 assert_size!(Hash, 28);
202 }
203
204 #[cfg(target_pointer_width = "64")]
205 #[test]
206 fn test_size() {
207 assert_size!(Algo, 32);
208 assert_size!(Hash, 56);
209 }
210
211 #[test]
212 fn test_simple() {
213 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=</hash>".parse().unwrap();
214 let hash = Hash::try_from(elem).unwrap();
215 assert_eq!(hash.algo, Algo::Sha_256);
216 assert_eq!(
217 hash.hash,
218 base64::decode("2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=").unwrap()
219 );
220 }
221
222 #[test]
223 fn value_serialisation() {
224 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=</hash>".parse().unwrap();
225 let hash = Hash::try_from(elem).unwrap();
226 assert_eq!(hash.to_base64(), "2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=");
227 assert_eq!(hash.to_hex(), "d976ab9b04e53710c0324bf29a5a17dd2e7e55bca536b26dfe5e50c8f6be6285");
228 assert_eq!(hash.to_colon_hex(), "d9:76:ab:9b:04:e5:37:10:c0:32:4b:f2:9a:5a:17:dd:2e:7e:55:bc:a5:36:b2:6d:fe:5e:50:c8:f6:be:62:85");
229 }
230
231 #[test]
232 fn test_unknown() {
233 let elem: Element = "<replace xmlns='urn:xmpp:message-correct:0'/>"
234 .parse()
235 .unwrap();
236 let error = Hash::try_from(elem).unwrap_err();
237 let message = match error {
238 Error::ParseError(string) => string,
239 _ => panic!(),
240 };
241 assert_eq!(message, "This is not a hash element.");
242 }
243
244 #[test]
245 fn test_invalid_child() {
246 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2'><coucou/></hash>"
247 .parse()
248 .unwrap();
249 let error = Hash::try_from(elem).unwrap_err();
250 let message = match error {
251 Error::ParseError(string) => string,
252 _ => panic!(),
253 };
254 assert_eq!(message, "Unknown child in hash element.");
255 }
256}