eme.rs

 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;
 8
 9use minidom::Element;
10
11use error::Error;
12
13use ns;
14
15/// Structure representing an `<encryption xmlns='urn:xmpp:eme:0'/>` element.
16#[derive(Debug, Clone)]
17pub struct ExplicitMessageEncryption {
18    /// Namespace of the encryption scheme used.
19    pub namespace: String,
20
21    /// User-friendly name for the encryption scheme, should be `None` for OTR,
22    /// legacy OpenPGP and OX.
23    pub name: Option<String>,
24}
25
26impl TryFrom<Element> for ExplicitMessageEncryption {
27    type Err = Error;
28
29    fn try_from(elem: Element) -> Result<ExplicitMessageEncryption, Error> {
30        if !elem.is("encryption", ns::EME) {
31            return Err(Error::ParseError("This is not an encryption element."));
32        }
33        for _ in elem.children() {
34            return Err(Error::ParseError("Unknown child in encryption element."));
35        }
36        Ok(ExplicitMessageEncryption {
37            namespace: get_attr!(elem, "namespace", required),
38            name: get_attr!(elem, "name", optional),
39        })
40    }
41}
42
43impl From<ExplicitMessageEncryption> for Element {
44    fn from(eme: ExplicitMessageEncryption) -> Element {
45        Element::builder("encryption")
46                .ns(ns::EME)
47                .attr("namespace", eme.namespace)
48                .attr("name", eme.name)
49                .build()
50    }
51}
52
53#[cfg(test)]
54mod tests {
55    use super::*;
56
57    #[test]
58    fn test_simple() {
59        let elem: Element = "<encryption xmlns='urn:xmpp:eme:0' namespace='urn:xmpp:otr:0'/>".parse().unwrap();
60        let encryption = ExplicitMessageEncryption::try_from(elem).unwrap();
61        assert_eq!(encryption.namespace, "urn:xmpp:otr:0");
62        assert_eq!(encryption.name, None);
63
64        let elem: Element = "<encryption xmlns='urn:xmpp:eme:0' namespace='some.unknown.mechanism' name='SuperMechanism'/>".parse().unwrap();
65        let encryption = ExplicitMessageEncryption::try_from(elem).unwrap();
66        assert_eq!(encryption.namespace, "some.unknown.mechanism");
67        assert_eq!(encryption.name, Some(String::from("SuperMechanism")));
68    }
69
70    #[test]
71    fn test_unknown() {
72        let elem: Element = "<replace xmlns='urn:xmpp:message-correct:0'/>".parse().unwrap();
73        let error = ExplicitMessageEncryption::try_from(elem).unwrap_err();
74        let message = match error {
75            Error::ParseError(string) => string,
76            _ => panic!(),
77        };
78        assert_eq!(message, "This is not an encryption element.");
79    }
80
81    #[test]
82    fn test_invalid_child() {
83        let elem: Element = "<encryption xmlns='urn:xmpp:eme:0'><coucou/></encryption>".parse().unwrap();
84        let error = ExplicitMessageEncryption::try_from(elem).unwrap_err();
85        let message = match error {
86            Error::ParseError(string) => string,
87            _ => panic!(),
88        };
89        assert_eq!(message, "Unknown child in encryption element.");
90    }
91
92    #[test]
93    fn test_serialise() {
94        let elem: Element = "<encryption xmlns='urn:xmpp:eme:0' namespace='coucou'/>".parse().unwrap();
95        let eme = ExplicitMessageEncryption { namespace: String::from("coucou"), name: None };
96        let elem2 = eme.into();
97        assert_eq!(elem, elem2);
98    }
99}