libsip 0.2.6

SIP protocol Implementation, with a focus towords softphone clients.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214

use sha::{
    sha256::Sha256,
    sha512::Sha512,
    utils::{Digest, DigestExt},
};

use std::{collections::HashMap, fmt, io::Result as IoResult};

use crate::Uri;

/// The SIP Authentication schema.
#[derive(Debug, PartialEq, Clone, Copy)]
pub enum AuthSchema {
    Digest,
}

impl fmt::Display for AuthSchema {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match self {
            AuthSchema::Digest => write!(f, "Digest"),
        }
    }
}

/// AuthHeader used for headers such as Authorization
/// or WWWAuthenticate.
#[derive(Debug, PartialEq, Clone)]
pub struct AuthHeader(pub AuthSchema, pub HashMap<String, String>);

impl fmt::Display for AuthHeader {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", self.0)?;
        for (index, (key, value)) in self.1.iter().enumerate() {
            if index == 0 && key == &"qop".to_string() {
                write!(f, "{}={}", key, value)?;
            } else if index == 0 && key == &"auth".to_string() {
                write!(f, "{}={:08}", key, value)?;
            } else if index == 0 {
                write!(f, " {}=\"{}\"", key, value)?;
            } else if key == &"qop".to_string() {
                write!(f, ", {}={}", key, value)?;
            } else if key == &"auth".to_string() {
                write!(f, ", {}={:08}", key, value)?;
            } else {
                write!(f, ", {}=\"{}\"", key, value)?;
            }
        }
        Ok(())
    }
}

/// Context struct used when calculating the Auth Headers.
pub struct AuthContext<'a> {
    pub user: &'a str,
    pub pass: &'a str,
    pub nc: u32,
    pub uri: &'a Uri,
}

impl AuthHeader {
    /// Perform the authenticate action.
    pub fn authenticate<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        match self.0 {
            AuthSchema::Digest => self.handle_digest_auth(ctx),
        }
    }

    /// Perform the Digest auth method.
    fn handle_digest_auth<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        let qop = self
            .1
            .get("qop")
            .expect("Auth header does not contain a qop field");
        match qop.as_ref() {
            "auth" => self.handle_digest_qop_auth(ctx),
            qop => panic!("unknown auth qop: {}", qop),
        }
    }

    /// Decides witch authorization algorythm to use.
    fn handle_digest_qop_auth<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        let alg = self
            .1
            .get("algorithm")
            .map(|item| item.to_string())
            .unwrap_or_else(|| "md5".to_string());
        match alg.as_ref() {
            "md5" | "MD5" => self.handle_md5_digest_auth(ctx),
            "sha-256" | "SHA-256" => self.handle_sha256_digest_auth(ctx),
            "sha-512-256" | "SHA-512-256" => self.handle_sha512_digest_auth(ctx),
            alg => panic!("Unknown Auth alogirithm: {}", alg),
        }
    }

    /// Handle the MD5 digest auth method.
    fn handle_md5_digest_auth<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        let realm = self
            .1
            .get("realm")
            .expect("Auth header does not contain a realm");
        let nonce = self
            .1
            .get("nonce")
            .expect("Auth header does not contain a nonce");
        let mut map: HashMap<String, String> = HashMap::new();
        let cnonce = self.generate_cnonce();
        map.insert("username".into(), ctx.user.to_string());
        map.insert("nonce".into(), nonce.to_string());
        map.insert("realm".into(), realm.clone());
        map.insert("uri".into(), format!("{}", ctx.uri));
        map.insert("qop".into(), self.1.get("qop").unwrap().clone());
        map.insert("algorithm".into(), "MD5".into());
        map.insert("cnonce".into(), format!("{:x}", cnonce));
        map.insert("nc".into(), format!("{:08}", ctx.nc));
        let ha1 = md5::compute(&format!("{}:{}:{}", ctx.user, realm, ctx.pass));
        let ha2 = md5::compute(format!("REGISTER:{}", ctx.uri));
        let digest = format!(
            "{:x}:{}:{:08}:{:x}:auth:{:x}",
            ha1, nonce, ctx.nc, cnonce, ha2
        );
        let pass = md5::compute(digest);
        map.insert("response".into(), format!("{:x}", pass));
        Ok(AuthHeader(AuthSchema::Digest, map))
    }

    /// Handle sha256 Digest auth method.
    fn handle_sha256_digest_auth<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        let realm = self
            .1
            .get("realm")
            .expect("Auth header does not contain a realm");
        let nonce = self
            .1
            .get("nonce")
            .expect("Auth header does not contain a nonce");
        let opaque = self
            .1
            .get("opaque")
            .expect("Auth header does not contain a opaque");
        let mut map: HashMap<String, String> = HashMap::new();
        let cnonce = self.generate_cnonce();
        map.insert("username".into(), ctx.user.to_string());
        map.insert("nonce".into(), nonce.to_string());
        map.insert("realm".into(), realm.clone());
        map.insert("uri".into(), format!("{}", ctx.uri));
        map.insert("qop".into(), self.1.get("qop").unwrap().clone());
        map.insert("algorithm".into(), "SHA-512-256".into());
        map.insert("cnonce".into(), format!("{:x}", cnonce));
        map.insert("nc".into(), format!("{:08}", ctx.nc));
        map.insert("opaque".into(), opaque.into());
        let mut ha1_hasher = Sha256::default();
        let ha1 = ha1_hasher.digest(format!("{}:{}:{}", ctx.user, realm, ctx.pass).as_ref());
        let mut ha2_hasher = Sha256::default();
        let ha2 = ha2_hasher.digest(format!("REGISTER:{}", ctx.uri).as_ref());
        let digest = format!(
            "{}:{}:{:08}:{:x}:auth:{}",
            ha1.to_hex(),
            nonce,
            ctx.nc,
            cnonce,
            ha2.to_hex()
        );
        let pass = md5::compute(digest);
        map.insert("response".into(), format!("{:x}", pass));
        Ok(AuthHeader(AuthSchema::Digest, map))
    }

    /// Handle sha512 auth method.
    fn handle_sha512_digest_auth<'a>(&self, ctx: AuthContext<'a>) -> IoResult<AuthHeader> {
        let realm = self
            .1
            .get("realm")
            .expect("Auth header does not contain a realm");
        let nonce = self
            .1
            .get("nonce")
            .expect("Auth header does not contain a nonce");
        let opaque = self
            .1
            .get("opaque")
            .expect("Auth header does not contain a opaque");
        let mut map: HashMap<String, String> = HashMap::new();
        let cnonce = self.generate_cnonce();
        map.insert("username".into(), ctx.user.to_string());
        map.insert("nonce".into(), nonce.to_string());
        map.insert("realm".into(), realm.clone());
        map.insert("uri".into(), format!("{}", ctx.uri));
        map.insert("qop".into(), self.1.get("qop").unwrap().clone());
        map.insert("algorithm".into(), "SHA-512".into());
        map.insert("cnonce".into(), format!("{:x}", cnonce));
        map.insert("nc".into(), format!("{:08}", ctx.nc));
        map.insert("opaque".into(), opaque.into());
        let mut ha1_hasher = Sha512::default();
        let ha1 = ha1_hasher.digest(format!("{}:{}:{}", ctx.user, realm, ctx.pass).as_ref());
        let mut ha2_hasher = Sha512::default();
        let ha2 = ha2_hasher.digest(format!("REGISTER:{}", ctx.uri).as_ref());
        let digest = format!(
            "{}:{}:{:08}:{:x}:auth:{}",
            ha1.to_hex(),
            nonce,
            ctx.nc,
            cnonce,
            ha2.to_hex()
        );
        let pass = md5::compute(digest);
        map.insert("response".into(), format!("{:x}", pass));
        Ok(AuthHeader(AuthSchema::Digest, map))
    }

    /// Generate the nonce used during authorization.
    fn generate_cnonce(&self) -> md5::Digest {
        md5::compute(rand::random::<[u8; 16]>())
    }
}