1 #[cfg(test)]
2 mod auth_test;
3
4 use crate::error::*;
5
6 use std::net::SocketAddr;
7 use std::time::{Duration, SystemTime, UNIX_EPOCH};
8
9 use md5::{Digest, Md5};
10 use ring::hmac;
11
12 pub trait AuthHandler {
auth_handle(&self, username: &str, realm: &str, src_addr: SocketAddr) -> Result<Vec<u8>>13 fn auth_handle(&self, username: &str, realm: &str, src_addr: SocketAddr) -> Result<Vec<u8>>;
14 }
15
16 // generate_long_term_credentials can be used to create credentials valid for [duration] time
generate_long_term_credentials( shared_secret: &str, duration: Duration, ) -> Result<(String, String)>17 pub fn generate_long_term_credentials(
18 shared_secret: &str,
19 duration: Duration,
20 ) -> Result<(String, String)> {
21 let t = SystemTime::now().duration_since(UNIX_EPOCH)? + duration;
22 let username = format!("{}", t.as_secs());
23 let password = long_term_credentials(&username, shared_secret);
24 Ok((username, password))
25 }
26
long_term_credentials(username: &str, shared_secret: &str) -> String27 fn long_term_credentials(username: &str, shared_secret: &str) -> String {
28 let mac = hmac::Key::new(
29 hmac::HMAC_SHA1_FOR_LEGACY_USE_ONLY,
30 shared_secret.as_bytes(),
31 );
32 let password = hmac::sign(&mac, username.as_bytes()).as_ref().to_vec();
33 base64::encode(password)
34 }
35
36 // generate_auth_key is a convenience function to easily generate keys in the format used by AuthHandler
generate_auth_key(username: &str, realm: &str, password: &str) -> Vec<u8>37 pub fn generate_auth_key(username: &str, realm: &str, password: &str) -> Vec<u8> {
38 let s = format!("{username}:{realm}:{password}");
39
40 let mut h = Md5::new();
41 h.update(s.as_bytes());
42 h.finalize().as_slice().to_vec()
43 }
44
45 pub struct LongTermAuthHandler {
46 shared_secret: String,
47 }
48
49 impl AuthHandler for LongTermAuthHandler {
auth_handle(&self, username: &str, realm: &str, src_addr: SocketAddr) -> Result<Vec<u8>>50 fn auth_handle(&self, username: &str, realm: &str, src_addr: SocketAddr) -> Result<Vec<u8>> {
51 log::trace!(
52 "Authentication username={} realm={} src_addr={}",
53 username,
54 realm,
55 src_addr
56 );
57
58 let t = Duration::from_secs(username.parse::<u64>()?);
59 if t < SystemTime::now().duration_since(UNIX_EPOCH)? {
60 return Err(Error::Other(format!(
61 "Expired time-windowed username {username}"
62 )));
63 }
64
65 let password = long_term_credentials(username, &self.shared_secret);
66 Ok(generate_auth_key(username, realm, &password))
67 }
68 }
69
70 impl LongTermAuthHandler {
71 // https://tools.ietf.org/search/rfc5389#section-10.2
new(shared_secret: String) -> Self72 pub fn new(shared_secret: String) -> Self {
73 LongTermAuthHandler { shared_secret }
74 }
75 }
76