✨ Replace random session tokens with JWE tokens.

We still maintain the http session state on the database for to prevent
replay attacks to the main application. But internally, on less critical
parts of the infraestructure, it usefull have access to the identified
user without hit the main database for that information.

backend/src/app/config.clj

@@ -116,7 +116,6 @@
 (s/def ::oidc-roles-attr ::us/keyword)
 (s/def ::host ::us/string)
 (s/def ::http-server-port ::us/integer)
-(s/def ::http-session-cookie-name ::us/string)
 (s/def ::http-session-idle-max-age ::dt/duration)
 (s/def ::http-session-updater-batch-max-age ::dt/duration)
 (s/def ::http-session-updater-batch-max-size ::us/integer)

backend/src/app/http/session.clj

@@ -21,86 +21,85 @@
    [clojure.spec.alpha :as s]
    [integrant.core :as ig]))
 
+;; A default cookie name for storing the session. We don't allow
+;; configure it.
+(def cookie-name "session-id")
+
 ;; --- IMPL
 
-(defn- next-session-id
-  ([] (next-session-id 96))
-  ([n]
-   (-> (bn/random-nonce n)
-       (bc/bytes->b64u)
-       (bc/bytes->str))))
-
-(defn- create
-  [{:keys [conn] :as cfg} {:keys [profile-id user-agent]}]
-  (let [id (next-session-id)]
-    (db/insert! conn :http-session {:id id
+(defn- create-session
+  [{:keys [conn tokens] :as cfg} {:keys [profile-id headers] :as request}]
+  (let [token  (tokens :generate {:iss "authentication"
+                                  :iat (dt/now)
+                                  :uid profile-id})
+        params {:user-agent (get headers "user-agent")
                 :profile-id profile-id
-                                    :user-agent user-agent})
-    id))
+                :id token}]
+    (db/insert! conn :http-session params)))
 
-(defn- delete
-  [{:keys [conn cookie-name] :as cfg} {:keys [cookies] :as request}]
+(defn- delete-session
+  [{:keys [conn] :as cfg} {:keys [cookies] :as request}]
   (when-let [token (get-in cookies [cookie-name :value])]
     (db/delete! conn :http-session {:id token}))
   nil)
 
-(defn- retrieve
-  [{:keys [conn] :as cfg} token]
-  (when token
-    (db/exec-one! conn ["select id, profile_id from http_session where id = ?" token])))
+(defn- retrieve-session
+  [{:keys [conn] :as cfg} id]
+  (when id
+    (db/exec-one! conn ["select id, profile_id from http_session where id = ?" id])))
 
 (defn- retrieve-from-request
-  [{:keys [cookie-name] :as cfg} {:keys [cookies] :as request}]
+  [cfg {:keys [cookies] :as request}]
   (->> (get-in cookies [cookie-name :value])
-       (retrieve cfg)))
+       (retrieve-session cfg)))
 
-(defn- cookies
-  [{:keys [cookie-name] :as cfg} vals]
-  {cookie-name (merge vals {:path "/" :http-only true})})
+(defn- add-cookies
+  [response {:keys [id] :as session}]
+  (assoc response :cookies {"session-id" {:path "/" :http-only true :value id}}))
+
+(defn- clear-cookies
+  [response]
+  (assoc response :cookies {"session-id" {:value "" :max-age -1}}))
 
 (defn- middleware
   [cfg handler]
   (fn [request]
     (if-let [{:keys [id profile-id] :as session} (retrieve-from-request cfg request)]
-      (let [events-ch (::events-ch cfg)]
-        (a/>!! events-ch id)
+      (do
+        (a/>!! (::events-ch cfg) id)
         (l/update-thread-context! {:profile-id profile-id})
         (handler (assoc request :profile-id profile-id)))
       (handler request))))
 
 ;; --- STATE INIT: SESSION
 
-(s/def ::cookie-name ::cfg/http-session-cookie-name)
-
 (defmethod ig/pre-init-spec ::session [_]
-  (s/keys :req-un [::db/pool]
-          :opt-un [::cookie-name]))
+  (s/keys :req-un [::db/pool]))
 
 (defmethod ig/prep-key ::session
   [_ cfg]
-  (merge {:cookie-name "auth-token"
-          :buffer-size 64}
+  (d/merge {:buffer-size 64}
            (d/without-nils cfg)))
 
 (defmethod ig/init-key ::session
   [_ {:keys [pool] :as cfg}]
   (let [events (a/chan (a/dropping-buffer (:buffer-size cfg)))
-        cfg    (assoc cfg
-                      :conn pool
-                      ::events-ch events)]
+        cfg    (-> cfg
+                   (assoc :conn pool)
+                   (assoc ::events-ch events))]
     (-> cfg
         (assoc :middleware #(middleware cfg %))
         (assoc :create (fn [profile-id]
                          (fn [request response]
-                           (let [uagent (get-in request [:headers "user-agent"])
-                                 value  (create cfg {:profile-id profile-id :user-agent uagent})]
-                             (assoc response :cookies (cookies cfg {:value value}))))))
+                           (let [request (assoc request :profile-id profile-id)
+                                 session (create-session cfg request)]
+                             (add-cookies response session)))))
         (assoc :delete (fn [request response]
-                         (delete cfg request)
-                         (assoc response
-                                :status 204
-                                :body ""
-                                :cookies (cookies cfg {:value "" :max-age -1})))))))
+                         (delete-session cfg request)
+                         (-> response
+                             (assoc :status 204)
+                             (assoc :body "")
+                             (clear-cookies)))))))
 
 (defmethod ig/halt-key! ::session
   [_ data]

backend/src/app/main.clj

@@ -61,7 +61,7 @@
 
    :app.http.session/session
    {:pool   (ig/ref :app.db/pool)
-    :cookie-name (cf/get :http-session-cookie-name)}
+    :tokens (ig/ref :app.tokens/tokens)}
 
    :app.http.session/gc-task
    {:pool        (ig/ref :app.db/pool)