auth: logging in, and tokens as bearers

POST /auth/login (by htpasswd or the proxy), /auth/refresh,
/auth/logout, GET /auth/whoami; every request may bring
Authorization: Bearer instead of a password. --token-lifetime and
--session-lifetime.

Auth plan M2.

1 files changed, 17 insertions, 4 deletions

diff --git a/src/api/auth.rs b/src/api/auth.rs
index f85b64e..69c7ddb 100644
--- a/src/api/auth.rs
+++ b/src/api/auth.rs
@@ -203,10 +203,16 @@ fn parse_basic(headers: &HeaderMap) -> Option<(String, String)> {
     Some((user.to_owned(), pass.to_owned()))
 }
 
-/// The user a request authenticated as (a request extension, set by [`basic_auth`]).
+/// The user a request authenticated as (a request extension, set by [`basic_auth`], or
+/// by `login::bearer` for a token).
 #[derive(Clone, Debug)]
 pub(crate) struct AuthenticatedUser(pub(crate) String);
 
+/// How the request's user proved who it is (a request extension, beside
+/// `AuthenticatedUser`): `htpasswd`, `header` (a trusted proxy's), or `token`.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(crate) struct Via(pub(crate) &'static str);
+
 /// The user the trusted proxy the request came from names, if it does.
 fn proxied_user(state: &AuthState, headers: &HeaderMap, from: Option<Peer>) -> Option<String> {
     let proxy = state.proxy.as_ref()?;
@@ -279,15 +285,21 @@ pub(crate) async fn basic_auth(
     mut request: Request<Body>,
     next: axum::middleware::Next,
 ) -> Response {
+    // A token, taken already (`login::bearer`).
+    if request.extensions().get::<AuthenticatedUser>().is_some() {
+        return next.run(request).await;
+    }
     let from = request
         .extensions()
         .get::<ConnectInfo<Peer>>()
         .map(|ConnectInfo(peer)| *peer);
     let user = match proxied_user(&state, &headers, from) {
-        Some(user) => Some(user),
-        None => authenticate(&state, &headers).await,
+        Some(user) => Some((user, Via("header"))),
+        None => authenticate(&state, &headers)
+            .await
+            .map(|user| (user, Via("htpasswd"))),
     };
-    let Some(user) = user else {
+    let Some((user, via)) = user else {
         sleep(Duration::from_millis(1500)).await;
         // A challenge only where basic authentication can answer it.
         return match state.users {
@@ -302,6 +314,7 @@ pub(crate) async fn basic_auth(
     };
 
     request.extensions_mut().insert(AuthenticatedUser(user));
+    request.extensions_mut().insert(via);
     next.run(request).await
 }