modo/auth/session/cookie/
middleware.rs

1use std::future::Future;
2use std::pin::Pin;
3use std::sync::atomic::{AtomicBool, Ordering};
4use std::sync::{Arc, Mutex};
5use std::task::{Context, Poll};
6
7use axum::body::Body;
8use axum::extract::connect_info::ConnectInfo;
9use cookie::{Cookie, CookieJar, SameSite};
10use http::{HeaderValue, Request, Response};
11use tower::{Layer, Service};
12
13use crate::ip::ClientIp;
14
15use super::CookieSessionService;
16use super::extractor::{SessionAction, SessionState};
17use crate::auth::session::data::Session;
18use crate::auth::session::meta::{SessionMeta, header_str};
19use crate::auth::session::token::SessionToken;
20use crate::cookie::{CookieConfig, Key};
21
22// --- Layer ---
23
24/// Tower [`Layer`] that installs the session middleware into the request pipeline.
25///
26/// Construct with [`layer`] or [`CookieSessionService::layer`] rather than
27/// directly. Apply before route handlers with `Router::layer(session_layer)`.
28///
29/// The middleware reads the signed session cookie, loads the session from the
30/// database, validates the browser fingerprint (when configured), and inserts:
31/// - an `Arc<SessionState>` for the [`super::extractor::CookieSession`] extractor
32/// - a [`crate::auth::session::data::Session`] snapshot for the data extractor
33///
34/// On the response path it flushes dirty session data, touches the expiry
35/// timestamp, and sets or clears the session cookie as needed.
36#[derive(Clone)]
37pub struct CookieSessionLayer {
38    service: CookieSessionService,
39}
40
41/// Create a [`CookieSessionLayer`] from a [`CookieSessionService`].
42pub fn layer(service: CookieSessionService) -> CookieSessionLayer {
43    CookieSessionLayer { service }
44}
45
46impl<S> Layer<S> for CookieSessionLayer {
47    type Service = CookieSessionMiddleware<S>;
48
49    fn layer(&self, inner: S) -> Self::Service {
50        CookieSessionMiddleware {
51            inner,
52            service: self.service.clone(),
53        }
54    }
55}
56
57// --- Service ---
58
59/// Tower [`Service`] that manages the session lifecycle for each request.
60///
61/// Produced by [`CookieSessionLayer`]; not constructed directly.
62#[derive(Clone)]
63pub struct CookieSessionMiddleware<S> {
64    inner: S,
65    service: CookieSessionService,
66}
67
68impl<S, ReqBody> Service<Request<ReqBody>> for CookieSessionMiddleware<S>
69where
70    S: Service<Request<ReqBody>, Response = Response<Body>> + Clone + Send + 'static,
71    S::Future: Send + 'static,
72    S::Error: Into<Box<dyn std::error::Error + Send + Sync>> + Send + 'static,
73    ReqBody: Send + 'static,
74{
75    type Response = Response<Body>;
76    type Error = S::Error;
77    type Future = Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>> + Send>>;
78
79    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
80        self.inner.poll_ready(cx)
81    }
82
83    fn call(&mut self, mut request: Request<ReqBody>) -> Self::Future {
84        let svc = self.service.clone();
85        let mut inner = self.inner.clone();
86        std::mem::swap(&mut self.inner, &mut inner);
87
88        Box::pin(async move {
89            let store = svc.store();
90            let config = store.config();
91            let cookie_name = &config.cookie_name;
92            let key = svc.cookie_key();
93            let cookie_config = svc.config().cookie.clone();
94
95            let ip = request
96                .extensions()
97                .get::<ClientIp>()
98                .map(|c| c.0.to_string())
99                .unwrap_or_else(|| {
100                    request
101                        .extensions()
102                        .get::<ConnectInfo<std::net::SocketAddr>>()
103                        .map(|ci| ci.0.ip().to_string())
104                        .unwrap_or_else(|| "unknown".to_string())
105                });
106            let headers = request.headers();
107
108            let ua = header_str(headers, "user-agent");
109            let accept_lang = header_str(headers, "accept-language");
110            let accept_enc = header_str(headers, "accept-encoding");
111            let meta = SessionMeta::from_headers(ip, ua, accept_lang, accept_enc);
112
113            let session_token = read_signed_cookie(request.headers(), cookie_name, key);
114            let had_cookie = session_token.is_some();
115
116            let (current_session, read_failed) = if let Some(ref token) = session_token {
117                match store.read_by_token(token).await {
118                    Ok(session) => (session, false),
119                    Err(e) => {
120                        tracing::error!("failed to read session: {e}");
121                        (None, true)
122                    }
123                }
124            } else {
125                (None, false)
126            };
127
128            let current_session = if let Some(session) = current_session {
129                if config.validate_fingerprint && meta.fingerprint != session.fingerprint {
130                    tracing::warn!(
131                        session_id = session.id,
132                        user_id = session.user_id,
133                        "session fingerprint mismatch — possible hijack, destroying session"
134                    );
135                    let _ = store.destroy(&session.id).await;
136                    None
137                } else {
138                    Some(session)
139                }
140            } else {
141                None
142            };
143
144            let should_touch = current_session.as_ref().is_some_and(|s| {
145                let elapsed = chrono::Utc::now() - s.last_active_at;
146                elapsed >= chrono::Duration::seconds(config.touch_interval_secs as i64)
147            });
148
149            if let Some(raw) = current_session.as_ref() {
150                let session_data = Session::from(raw.clone());
151                request.extensions_mut().insert(session_data);
152            }
153
154            let session_state = Arc::new(SessionState {
155                service: svc.clone(),
156                meta,
157                current: Mutex::new(current_session.clone()),
158                dirty: AtomicBool::new(false),
159                action: Mutex::new(SessionAction::None),
160            });
161
162            request.extensions_mut().insert(session_state.clone());
163
164            let mut response = inner.call(request).await?;
165
166            let action = {
167                let guard = session_state.action.lock().expect("session mutex poisoned");
168                guard.clone()
169            };
170            let is_dirty = session_state.dirty.load(Ordering::SeqCst);
171            let ttl_secs = config.session_ttl_secs;
172
173            match action {
174                SessionAction::Set(token) => {
175                    set_signed_cookie(
176                        &mut response,
177                        cookie_name,
178                        &token.as_hex(),
179                        ttl_secs,
180                        &cookie_config,
181                        key,
182                    );
183                }
184                SessionAction::Remove => {
185                    remove_signed_cookie(&mut response, cookie_name, &cookie_config, key);
186                }
187                SessionAction::None => {
188                    if let Some(ref session) = current_session {
189                        let now = chrono::Utc::now();
190                        let new_expires = now + chrono::Duration::seconds(ttl_secs as i64);
191
192                        if is_dirty {
193                            let data = {
194                                let guard = session_state
195                                    .current
196                                    .lock()
197                                    .expect("session mutex poisoned");
198                                guard.as_ref().map(|s| s.data.clone())
199                            };
200                            if let Some(data) = data
201                                && let Err(e) =
202                                    store.flush(&session.id, &data, now, new_expires).await
203                            {
204                                tracing::error!(
205                                    session_id = session.id,
206                                    "failed to flush session data: {e}"
207                                );
208                            }
209                        } else if should_touch
210                            && let Err(e) = store.touch(&session.id, now, new_expires).await
211                        {
212                            tracing::error!(
213                                session_id = session.id,
214                                "failed to touch session: {e}"
215                            );
216                        }
217
218                        if (is_dirty || should_touch)
219                            && let Some(ref token) = session_token
220                        {
221                            set_signed_cookie(
222                                &mut response,
223                                cookie_name,
224                                &token.as_hex(),
225                                ttl_secs,
226                                &cookie_config,
227                                key,
228                            );
229                        }
230                    }
231
232                    if had_cookie && current_session.is_none() && !read_failed {
233                        remove_signed_cookie(&mut response, cookie_name, &cookie_config, key);
234                    }
235                }
236            }
237
238            Ok(response)
239        })
240    }
241}
242
243/// Read a signed cookie value from request headers.
244/// Returns `Some(SessionToken)` if the cookie exists, signature is valid, and hex decodes.
245fn read_signed_cookie(
246    headers: &http::HeaderMap,
247    cookie_name: &str,
248    key: &Key,
249) -> Option<SessionToken> {
250    let cookie_header = headers.get(http::header::COOKIE)?;
251    let cookie_str = cookie_header.to_str().ok()?;
252
253    for pair in cookie_str.split(';') {
254        let pair = pair.trim();
255        if let Some((name, value)) = pair.split_once('=')
256            && name.trim() == cookie_name
257        {
258            let mut jar = CookieJar::new();
259            jar.add_original(Cookie::new(
260                cookie_name.to_string(),
261                value.trim().to_string(),
262            ));
263            let verified = jar.signed(key).get(cookie_name)?;
264            return SessionToken::from_hex(verified.value()).ok();
265        }
266    }
267    None
268}
269
270/// Sign a cookie value and append Set-Cookie header to response.
271fn set_signed_cookie(
272    response: &mut Response<Body>,
273    name: &str,
274    value: &str,
275    max_age_secs: u64,
276    config: &CookieConfig,
277    key: &Key,
278) {
279    // Sign the value
280    let mut jar = CookieJar::new();
281    jar.signed_mut(key)
282        .add(Cookie::new(name.to_string(), value.to_string()));
283    let signed_value = jar
284        .get(name)
285        .expect("cookie was just added")
286        .value()
287        .to_string();
288
289    let same_site = match config.same_site.as_str() {
290        "strict" => SameSite::Strict,
291        "none" => SameSite::None,
292        _ => SameSite::Lax,
293    };
294    let set_cookie_str = Cookie::build((name.to_string(), signed_value))
295        .path("/")
296        .secure(config.secure)
297        .http_only(config.http_only)
298        .same_site(same_site)
299        .max_age(cookie::time::Duration::seconds(max_age_secs as i64))
300        .build()
301        .to_string();
302
303    match HeaderValue::from_str(&set_cookie_str) {
304        Ok(v) => {
305            response.headers_mut().append(http::header::SET_COOKIE, v);
306        }
307        Err(e) => {
308            tracing::error!(
309                cookie_name = name,
310                "failed to set session cookie header: {e}"
311            );
312        }
313    }
314}
315
316fn remove_signed_cookie(
317    response: &mut Response<Body>,
318    name: &str,
319    config: &CookieConfig,
320    key: &Key,
321) {
322    set_signed_cookie(response, name, "", 0, config, key);
323}
modo/auth/session/cookie/middleware.rs

modo/auth/session/cookie/
middleware.rs
