OXYGENHUB
# 0e04dfc20211 oxygenhub / crates / hub / src / auth / viewer.rs
3.0 KiB · Rust · last changed Admins disable, enable and delete accounts 1 month ago source blame history raw
1 
//! Who is asking: the session cookie resolved to an account, as an axum
2 
//! extractor every page handler takes.
3
4 
use super::{csrf_token, mac_equal, session_value, SESSION_COOKIE};
5 
use crate::db::{self, accounts::Account};
6 
use crate::Shared;
7 
use axum::extract::FromRequestParts;
8 
use axum::http::request::Parts;
9 
use axum::http::{header, HeaderMap};
10 
use std::convert::Infallible;
11
12 
#[derive(Clone, Debug)]
13 
pub struct ViewerAccount {
14 
    pub account: Account,
15 
    /// The cookie value, which CSRF tokens are bound to.
16 
    pub session: String,
17 
    pub csrf: String,
18 
    /// Unread notifications, for the header.
19 
    pub unread: i64,
20 
}
21
22 
/// The signed-in account, if any. Never fails: anonymous is a valid viewer.
23 
#[derive(Clone, Debug, Default)]
24 
pub struct Viewer(pub Option<ViewerAccount>);
25
26 
impl Viewer {
27 
    pub fn account(&self) -> Option<&Account> {
28 
        self.0.as_ref().map(|v| &v.account)
29 
    }
30
31 
    pub fn signed_in(&self) -> bool {
32 
        self.0.is_some()
33 
    }
34
35 
    pub fn is_admin(&self) -> bool {
36 
        self.account().is_some_and(|a| a.is_admin)
37 
    }
38
39 
    pub fn csrf(&self) -> &str {
40 
        self.0.as_ref().map(|v| v.csrf.as_str()).unwrap_or("")
41 
    }
42
43 
    /// Whether a submitted CSRF token belongs to this session.
44 
    pub fn csrf_ok(&self, token: &str) -> bool {
45 
        self.0.as_ref().is_some_and(|v| mac_equal(&v.csrf, token))
46 
    }
47 
}
48
49 
/// The value of a named cookie in the request.
50 
pub fn cookie(headers: &HeaderMap, name: &str) -> Option<String> {
51 
    headers.get_all(header::COOKIE).iter().filter_map(|v| v.to_str().ok()).flat_map(|line| line.split(';')).find_map(|kv| {
52 
        let (k, v) = kv.trim().split_once('=')?;
53 
        (k == name).then(|| v.trim().to_string())
54 
    })
55 
}
56
57 
/// Resolve a session cookie value to its account.
58 
pub async fn resolve(app: &Shared, value: &str) -> Option<ViewerAccount> {
59 
    let (username, mac) = value.rsplit_once('.')?;
60 
    let account = db::accounts::account_by_name(&app.db, username).await.ok()??;
61 
    if account.blocked() {
62 
        return None;
63 
    }
64 
    let expected = session_value(&app.cookie_key, &account.username, &account.session_salt);
65 
    let (_, expected_mac) = expected.rsplit_once('.')?;
66 
    if !mac_equal(expected_mac, mac) {
67 
        return None;
68 
    }
69 
    let csrf = csrf_token(&app.cookie_key, &expected);
70 
    let unread = db::notify::unread(&app.db, account.id).await.unwrap_or(0);
71 
    Some(ViewerAccount { account, session: expected, csrf, unread })
72 
}
73
74 
impl FromRequestParts<Shared> for Viewer {
75 
    type Rejection = Infallible;
76
77 
    async fn from_request_parts(parts: &mut Parts, app: &Shared) -> Result<Viewer, Infallible> {
78 
        let Some(value) = cookie(&parts.headers, SESSION_COOKIE) else { return Ok(Viewer(None)) };
79 
        let viewer = resolve(app, &value).await;
80 
        if let Some(v) = &viewer {
81 
            let pool = app.db.clone();
82 
            let id = v.account.id;
83 
            tokio::spawn(async move {
84 
                let _ = db::accounts::touch_seen(&pool, id).await;
85 
            });
86 
        }
87 
        Ok(Viewer(viewer))
88 
    }
89 
}