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;
8use std::str::FromStr;
9
10use minidom::{Element, IntoAttributeValue};
11
12use error::Error;
13
14use ns;
15
16#[allow(non_camel_case_types)]
17#[derive(Debug, Clone, PartialEq)]
18pub enum Algo {
19 Sha_1,
20 Sha_256,
21 Sha_512,
22 Sha3_256,
23 Sha3_512,
24 Blake2b_256,
25 Blake2b_512,
26 Unknown(String),
27}
28
29impl FromStr for Algo {
30 type Err = Error;
31
32 fn from_str(s: &str) -> Result<Algo, Error> {
33 Ok(match s {
34 "" => return Err(Error::ParseError("'algo' argument can’t be empty.")),
35
36 "sha-1" => Algo::Sha_1,
37 "sha-256" => Algo::Sha_256,
38 "sha-512" => Algo::Sha_512,
39 "sha3-256" => Algo::Sha3_256,
40 "sha3-512" => Algo::Sha3_512,
41 "blake2b-256" => Algo::Blake2b_256,
42 "blake2b-512" => Algo::Blake2b_512,
43 value => Algo::Unknown(value.to_owned()),
44 })
45 }
46}
47
48impl IntoAttributeValue for Algo {
49 fn into_attribute_value(self) -> Option<String> {
50 Some(String::from(match self {
51 Algo::Sha_1 => "sha-1",
52 Algo::Sha_256 => "sha-256",
53 Algo::Sha_512 => "sha-512",
54 Algo::Sha3_256 => "sha3-256",
55 Algo::Sha3_512 => "sha3-512",
56 Algo::Blake2b_256 => "blake2b-256",
57 Algo::Blake2b_512 => "blake2b-512",
58 Algo::Unknown(text) => return Some(text),
59 }))
60 }
61}
62
63#[derive(Debug, Clone, PartialEq)]
64pub struct Hash {
65 pub algo: Algo,
66 pub hash: String,
67}
68
69impl<'a> TryFrom<&'a Element> for Hash {
70 type Error = Error;
71
72 fn try_from(elem: &'a Element) -> Result<Hash, Error> {
73 if !elem.is("hash", ns::HASHES) {
74 return Err(Error::ParseError("This is not a hash element."));
75 }
76 for _ in elem.children() {
77 return Err(Error::ParseError("Unknown child in hash element."));
78 }
79 let algo = match elem.attr("algo") {
80 None => Err(Error::ParseError("Mandatory argument 'algo' not present in hash element.")),
81 Some(text) => Algo::from_str(text),
82 }?;
83 let hash = match elem.text().as_ref() {
84 "" => return Err(Error::ParseError("Hash element shouldn’t be empty.")),
85 text => text.to_owned(),
86 };
87 Ok(Hash {
88 algo: algo,
89 hash: hash,
90 })
91 }
92}
93
94impl<'a> Into<Element> for &'a Hash {
95 fn into(self) -> Element {
96 Element::builder("hash")
97 .ns(ns::HASHES)
98 .attr("algo", self.algo.clone())
99 .append(self.hash.clone())
100 .build()
101 }
102}
103
104#[cfg(test)]
105mod tests {
106 use super::*;
107
108 #[test]
109 fn test_simple() {
110 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2' algo='sha-256'>2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=</hash>".parse().unwrap();
111 let hash = Hash::try_from(&elem).unwrap();
112 assert_eq!(hash.algo, Algo::Sha_256);
113 assert_eq!(hash.hash, "2XarmwTlNxDAMkvymloX3S5+VbylNrJt/l5QyPa+YoU=");
114 }
115
116 #[test]
117 fn test_unknown() {
118 let elem: Element = "<replace xmlns='urn:xmpp:message-correct:0'/>".parse().unwrap();
119 let error = Hash::try_from(&elem).unwrap_err();
120 let message = match error {
121 Error::ParseError(string) => string,
122 _ => panic!(),
123 };
124 assert_eq!(message, "This is not a hash element.");
125 }
126
127 #[test]
128 fn test_invalid_child() {
129 let elem: Element = "<hash xmlns='urn:xmpp:hashes:2'><coucou/></hash>".parse().unwrap();
130 let error = Hash::try_from(&elem).unwrap_err();
131 let message = match error {
132 Error::ParseError(string) => string,
133 _ => panic!(),
134 };
135 assert_eq!(message, "Unknown child in hash element.");
136 }
137}