refactor: moved auth business logic outside of db using store abstraction

src/cli/serve.rs

@@ -6,9 +6,11 @@ pub fn serve(config: &crate::config::Config) -> u8 {
     tracing::info!("Initializing database and running migrations");
 
     let pool = db::initialize_db(config.data_dir.join(crate::DB_FILENAME), true).unwrap();
+    let repo = db::SqliteRepository::from(pool);
 
     let ctx = server::Context {
-        repo: db::SqliteRepository::from(pool),
+        repo: repo.clone(),
+        store: crate::gpodder::GpodderRepository::new(Box::new(repo)),
     };
     let app = server::app(ctx);
 

src/db/repository/auth.rs

@@ -1,3 +1,4 @@
+use chrono::DateTime;
 use diesel::prelude::*;
 use rand::Rng;
 
@@ -19,6 +20,16 @@ impl From<diesel::result::Error> for gpodder::AuthErr {
     }
 }
 
+impl From<db::User> for gpodder::User {
+    fn from(value: db::User) -> Self {
+        Self {
+            id: value.id,
+            username: value.username,
+            password_hash: value.password_hash,
+        }
+    }
+}
+
 impl gpodder::AuthRepository for SqliteRepository {
     fn validate_credentials(
         &self,
@@ -35,6 +46,7 @@ impl gpodder::AuthRepository for SqliteRepository {
                 Ok(gpodder::User {
                     id: user.id,
                     username: user.username,
+                    password_hash: user.password_hash,
                 })
             } else {
                 Err(gpodder::AuthErr::InvalidPassword)
@@ -54,6 +66,7 @@ impl gpodder::AuthRepository for SqliteRepository {
             Ok(user) => Ok(gpodder::User {
                 id: user.id,
                 username: user.username,
+                password_hash: user.password_hash,
             }),
             Err(diesel::result::Error::NotFound) => Err(gpodder::AuthErr::UnknownSession),
             Err(err) => Err(gpodder::AuthErr::Other(Box::new(err))),
@@ -88,6 +101,7 @@ impl gpodder::AuthRepository for SqliteRepository {
                     gpodder::User {
                         id: user.id,
                         username: user.username,
+                        password_hash: user.password_hash,
                     },
                 ))
             } else {
@@ -122,3 +136,49 @@ impl gpodder::AuthRepository for SqliteRepository {
         }
     }
 }
+
+impl gpodder::AuthStore for SqliteRepository {
+    fn get_user(&self, username: &str) -> Result<Option<gpodder::models::User>, AuthErr> {
+        Ok(users::table
+            .select(db::User::as_select())
+            .filter(users::username.eq(username))
+            .first(&mut self.pool.get()?)
+            .optional()?
+            .map(gpodder::User::from))
+    }
+
+    fn get_session(&self, session_id: i64) -> Result<Option<gpodder::models::Session>, AuthErr> {
+        match sessions::table
+            .inner_join(users::table)
+            .filter(sessions::id.eq(session_id))
+            .select((db::Session::as_select(), db::User::as_select()))
+            .get_result(&mut self.pool.get()?)
+        {
+            Ok((session, user)) => Ok(Some(gpodder::Session {
+                id: session.id,
+                last_seen: DateTime::from_timestamp(session.last_seen, 0).unwrap(),
+                user: user.into(),
+            })),
+            Err(err) => Err(AuthErr::from(err)),
+        }
+    }
+
+    fn remove_session(&self, session_id: i64) -> Result<(), AuthErr> {
+        Ok(
+            diesel::delete(sessions::table.filter(sessions::id.eq(session_id)))
+                .execute(&mut self.pool.get()?)
+                .map(|_| ())?,
+        )
+    }
+
+    fn insert_session(&self, session: &gpodder::Session) -> Result<(), AuthErr> {
+        Ok(db::Session {
+            id: session.id,
+            user_id: session.user.id,
+            last_seen: session.last_seen.timestamp(),
+        }
+        .insert_into(sessions::table)
+        .execute(&mut self.pool.get()?)
+        .map(|_| ())?)
+    }
+}

src/gpodder/mod.rs

@@ -1,6 +1,8 @@
 pub mod models;
+mod repository;
 
 pub use models::*;
+pub use repository::GpodderRepository;
 
 pub enum AuthErr {
     UnknownSession,
@@ -27,6 +29,20 @@ pub trait AuthRepository {
     fn remove_session(&self, username: &str, session_id: i64) -> Result<(), AuthErr>;
 }
 
+pub trait AuthStore {
+    /// Retrieve the session with the given session ID
+    fn get_session(&self, session_id: i64) -> Result<Option<models::Session>, AuthErr>;
+
+    /// Retrieve the user with the given username
+    fn get_user(&self, username: &str) -> Result<Option<models::User>, AuthErr>;
+
+    /// Create a new session for a user with the given session ID
+    fn insert_session(&self, session: &Session) -> Result<(), AuthErr>;
+
+    /// Remove the session with the given session ID
+    fn remove_session(&self, session_id: i64) -> Result<(), AuthErr>;
+}
+
 pub trait DeviceRepository {
     /// Return all devices associated with the user
     fn devices_for_user(&self, user: &User) -> Result<Vec<Device>, AuthErr>;

src/gpodder/models.rs

@@ -1,10 +1,11 @@
-use chrono::NaiveDateTime;
+use chrono::{DateTime, NaiveDateTime, Utc};
 use serde::{Deserialize, Serialize};
 
 #[derive(Clone)]
 pub struct User {
     pub id: i64,
     pub username: String,
+    pub password_hash: String,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -57,3 +58,9 @@ pub struct EpisodeAction {
     #[serde(flatten)]
     pub action: EpisodeActionType,
 }
+
+pub struct Session {
+    pub id: i64,
+    pub last_seen: DateTime<Utc>,
+    pub user: User,
+}

src/gpodder/repository.rs

@@ -0,0 +1,74 @@
+use std::sync::Arc;
+
+use argon2::{Argon2, PasswordHash, PasswordVerifier};
+use rand::Rng;
+
+use super::{models, AuthErr, AuthStore};
+
+const MAX_SESSION_AGE: i64 = 60 * 60 * 24 * 7;
+
+type Store = dyn AuthStore + Send + Sync;
+
+#[derive(Clone)]
+pub struct GpodderRepository {
+    store: Arc<Store>,
+}
+
+impl GpodderRepository {
+    pub fn new(store: Box<Store>) -> Self {
+        Self {
+            store: Arc::from(store),
+        }
+    }
+
+    pub fn validate_session(&self, session_id: i64) -> Result<models::Session, AuthErr> {
+        let session = self
+            .store
+            .get_session(session_id)?
+            .ok_or(AuthErr::UnknownSession)?;
+
+        // Expired sessions still in the database are considered removed
+        if chrono::Utc::now() - session.last_seen
+            > chrono::TimeDelta::new(MAX_SESSION_AGE, 0).unwrap()
+        {
+            Err(AuthErr::UnknownSession)
+        } else {
+            Ok(session)
+        }
+    }
+
+    pub fn validate_credentials(
+        &self,
+        username: &str,
+        password: &str,
+    ) -> Result<models::User, AuthErr> {
+        let user = self.store.get_user(username)?.ok_or(AuthErr::UnknownUser)?;
+
+        let password_hash = PasswordHash::new(&user.password_hash).unwrap();
+
+        if Argon2::default()
+            .verify_password(password.as_bytes(), &password_hash)
+            .is_ok()
+        {
+            Ok(user)
+        } else {
+            Err(AuthErr::InvalidPassword)
+        }
+    }
+
+    pub fn create_session(&self, user: &models::User) -> Result<models::Session, AuthErr> {
+        let session = models::Session {
+            id: rand::thread_rng().gen(),
+            last_seen: chrono::Utc::now(),
+            user: user.clone(),
+        };
+
+        self.store.insert_session(&session)?;
+
+        Ok(session)
+    }
+
+    pub fn remove_session(&self, session_id: i64) -> Result<(), AuthErr> {
+        self.store.remove_session(session_id)
+    }
+}

src/server/gpodder/advanced/auth.rs

@@ -12,13 +12,10 @@ use axum_extra::{
     TypedHeader,
 };
 
-use crate::{
-    gpodder::AuthRepository,
-    server::{
-        error::{AppError, AppResult},
-        gpodder::SESSION_ID_COOKIE,
-        Context,
-    },
+use crate::server::{
+    error::{AppError, AppResult},
+    gpodder::SESSION_ID_COOKIE,
+    Context,
 };
 
 pub fn router() -> Router<Context> {
@@ -38,14 +35,17 @@ async fn post_login(
         return Err(AppError::BadRequest);
     }
 
-    let (session_id, _) = tokio::task::spawn_blocking(move || {
-        ctx.repo.create_session(auth.username(), auth.password())
+    let session = tokio::task::spawn_blocking(move || {
+        let user = ctx
+            .store
+            .validate_credentials(auth.username(), auth.password())?;
+        ctx.store.create_session(&user)
     })
     .await
     .unwrap()?;
 
     Ok(jar.add(
-        Cookie::build((SESSION_ID_COOKIE, session_id.to_string())).expires(Expiration::Session),
+        Cookie::build((SESSION_ID_COOKIE, session.id.to_string())).expires(Expiration::Session),
     ))
 }
 
@@ -60,7 +60,8 @@ async fn post_logout(
             .parse()
             .map_err(|_| AppError::BadRequest)?;
 
-        tokio::task::spawn_blocking(move || ctx.repo.remove_session(&username, session_id))
+        // TODO reintroduce username check
+        tokio::task::spawn_blocking(move || ctx.store.remove_session(session_id))
             .await
             .unwrap()?;
 

src/server/gpodder/mod.rs

@@ -17,10 +17,7 @@ use axum_extra::{
 };
 use tower_http::set_header::SetResponseHeaderLayer;
 
-use crate::{
-    gpodder::{self, AuthRepository},
-    server::error::AppError,
-};
+use crate::{gpodder, server::error::AppError};
 
 use super::Context;
 
@@ -51,12 +48,12 @@ pub async fn auth_middleware(State(ctx): State<Context>, mut req: Request, next:
         .and_then(|c| c.value().parse::<i64>().ok())
     {
         let ctx_clone = ctx.clone();
-        match tokio::task::spawn_blocking(move || ctx_clone.repo.validate_session(session_id))
+        match tokio::task::spawn_blocking(move || ctx_clone.store.validate_session(session_id))
             .await
             .unwrap()
         {
-            Ok(user) => {
-                auth_user = Some(user);
+            Ok(session) => {
+                auth_user = Some(session.user);
             }
             Err(gpodder::AuthErr::UnknownSession) => {
                 jar = jar.add(
@@ -77,7 +74,7 @@ pub async fn auth_middleware(State(ctx): State<Context>, mut req: Request, next:
             .await
         {
             match tokio::task::spawn_blocking(move || {
-                ctx.repo
+                ctx.store
                     .validate_credentials(auth.username(), auth.password())
             })
             .await

src/server/mod.rs

@@ -7,6 +7,7 @@ use tower_http::trace::TraceLayer;
 #[derive(Clone)]
 pub struct Context {
     pub repo: crate::db::SqliteRepository,
+    pub store: crate::gpodder::GpodderRepository,
 }
 
 pub fn app(ctx: Context) -> Router {