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 try_from::TryFrom;
8use std::str::FromStr;
9
10use minidom::{Element, IntoAttributeValue};
11
12use error::Error;
13
14use ns;
15
16use base64;
17
18#[allow(non_camel_case_types)]
19#[derive(Debug, Clone, PartialEq, Eq, Hash)]
20pub enum Algo {
21 Sha_1,
22 Sha_256,
23 Sha_512,
24 Sha3_256,
25 Sha3_512,
26 Blake2b_256,
27 Blake2b_512,
28 Unknown(String),
29}
30
31impl FromStr for Algo {
32 type Err = Error;
33
34 fn from_str(s: &str) -> Result<Algo, Error> {
35 Ok(match s {
36 "" => return Err(Error::ParseError("'algo' argument can’t be empty.")),
37
38 "sha-1" => Algo::Sha_1,
39 "sha-256" => Algo::Sha_256,
40 "sha-512" => Algo::Sha_512,
41 "sha3-256" => Algo::Sha3_256,
42 "sha3-512" => Algo::Sha3_512,
43 "blake2b-256" => Algo::Blake2b_256,
44 "blake2b-512" => Algo::Blake2b_512,
45 value => Algo::Unknown(value.to_owned()),
46 })
47 }
48}
49
50impl From<Algo> for String {
51 fn from(algo: Algo) -> String {
52 String::from(match algo {
53 Algo::Sha_1 => "sha-1",
54 Algo::Sha_256 => "sha-256",
55 Algo::Sha_512 => "sha-512",
56 Algo::Sha3_256 => "sha3-256",
57 Algo::Sha3_512 => "sha3-512",
58 Algo::Blake2b_256 => "blake2b-256",
59 Algo::Blake2b_512 => "blake2b-512",
60 Algo::Unknown(text) => return text,
61 })
62 }
63}
64
65impl IntoAttributeValue for Algo {
66 fn into_attribute_value(self) -> Option<String> {
67 Some(String::from(self))
68 }
69}
70
71#[derive(Debug, Clone, PartialEq, Eq, Hash)]
72pub struct Hash {
73 pub algo: Algo,
74 pub hash: Vec<u8>,
75}
76
77impl TryFrom<Element> for Hash {
78 type Err = Error;
79
80 fn try_from(elem: Element) -> Result<Hash, Error> {
81 if !elem.is("hash", ns::HASHES) {
82 return Err(Error::ParseError("This is not a hash element."));
83 }
84 for _ in elem.children() {
85 return Err(Error::ParseError("Unknown child in hash element."));
86 }
87 let algo = get_attr!(elem, "algo", required);
88 let hash = match elem.text().as_ref() {
89 "" => return Err(Error::ParseError("Hash element shouldn’t be empty.")),
90 text => base64::decode(text)?,
91 };
92 Ok(Hash {
93 algo: algo,
94 hash: hash,
95 })
96 }
97}
98
99impl From<Hash> for Element {
100 fn from(hash: Hash) -> Element {
101 Element::builder("hash")
102 .ns(ns::HASHES)
103 .attr("algo", hash.algo)
104 .append(base64::encode(&hash.hash))
105 .build()
106 }
107}
108
109#[cfg(test)]
110mod tests {
111 use super::*;
112
113 #[test]
114 fn test_simple() {
115 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=</hash>".parse().unwrap();
116 let hash = Hash::try_from(elem).unwrap();
117 assert_eq!(hash.algo, Algo::Sha_256);
118 assert_eq!(hash.hash, base64::decode("2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=").unwrap());
119 }
120
121 #[test]
122 fn test_unknown() {
123 let elem: Element = "<replace xmlns='urn:xmpp:message-correct:0'/>".parse().unwrap();
124 let error = Hash::try_from(elem).unwrap_err();
125 let message = match error {
126 Error::ParseError(string) => string,
127 _ => panic!(),
128 };
129 assert_eq!(message, "This is not a hash element.");
130 }
131
132 #[test]
133 fn test_invalid_child() {
134 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2'><coucou/></hash>".parse().unwrap();
135 let error = Hash::try_from(elem).unwrap_err();
136 let message = match error {
137 Error::ParseError(string) => string,
138 _ => panic!(),
139 };
140 assert_eq!(message, "Unknown child in hash element.");
141 }
142}