Store token and callback URI in memory session

shard.lock

@@ -28,6 +28,10 @@ shards:
     github: kemalcr/kemal
     version: 0.26.1
 
+  kemal-session:
+    github: kemalcr/kemal-session
+    version: 0.12.1
+
   kilt:
     github: jeromegn/kilt
     version: 0.4.0

shard.yml

@@ -15,6 +15,8 @@ license: MIT
 dependencies:
   kemal:
     github: kemalcr/kemal
+  kemal-session:
+    github: kemalcr/kemal-session
   sqlite3:
     github: crystal-lang/crystal-sqlite3
   baked_file_system:

src/config.cr

@@ -5,6 +5,7 @@ class Config
 
   property port : Int32 = 9000
   property base_url : String = "/"
+  property session_secret : String = "mango-session-secret"
   property library_path : String = File.expand_path "~/mango/library",
     home: true
   property db_path : String = File.expand_path "~/mango/mango.db", home: true

src/handlers/auth_handler.cr

@@ -21,18 +21,14 @@ class AuthHandler < Kemal::Handler
     call_next env
   end
 
-  def validate_cookie_token(env)
-    cookie = env.request.cookies.find do |c|
-      c.name == "token-#{Config.current.port}"
-    end
-    !cookie.nil? && @storage.verify_token cookie.value
+  def validate_token(env)
+    token = env.session.string? "token"
+    !token.nil? && @storage.verify_token token
   end
 
-  def validate_cookie_token_admin(env)
-    cookie = env.request.cookies.find do |c|
-      c.name == "token-#{Config.current.port}"
-    end
-    !cookie.nil? && @storage.verify_admin cookie.value
+  def validate_token_admin(env)
+    token = env.session.string? "token"
+    !token.nil? && @storage.verify_admin token
   end
 
   def validate_auth_header(env)
@@ -42,7 +38,7 @@ class AuthHandler < Kemal::Handler
           token = verify_user value
           return false if token.nil?
 
-          set_token_cookie env, token
+          env.session.string "token", token
           return true
         end
       end
@@ -57,7 +53,7 @@ class AuthHandler < Kemal::Handler
   end
 
   def handle_opds_auth(env)
-    if validate_cookie_token(env) || validate_auth_header(env)
+    if validate_token(env) || validate_auth_header(env)
       call_next env
     else
       env.response.status_code = 401
@@ -69,12 +65,13 @@ class AuthHandler < Kemal::Handler
   def handle_auth(env)
     return call_next(env) if request_path_startswith env, ["/login", "/logout"]
 
-    unless validate_cookie_token env
+    unless validate_token env
+      env.session.string "callback", env.request.path
       return redirect env, "/login"
     end
 
     if request_path_startswith env, ["/admin", "/api/admin", "/download"]
-      unless validate_cookie_token_admin env
+      unless validate_token_admin env
         env.response.status_code = 403
       end
     end

src/routes/main.cr

@@ -9,10 +9,7 @@ class MainRouter < Router
 
     get "/logout" do |env|
       begin
-        cookie = env.request.cookies.find do |c|
-          c.name == "token-#{Config.current.port}"
-        end.not_nil!
-        @context.storage.logout cookie.value
+        env.session.delete_string "token"
       rescue e
         @context.error "Error when attempting to log out: #{e}"
       ensure
@@ -26,8 +23,15 @@ class MainRouter < Router
         password = env.params.body["password"]
         token = @context.storage.verify_user(username, password).not_nil!
 
-        set_token_cookie env, token
+        env.session.string "token", token
+
+        callback = env.session.string? "callback"
+        if callback
+          env.session.delete_string "callback"
+          redirect env, callback
+        else
           redirect env, "/"
+        end
       rescue
         redirect env, "/login"
       end

src/server.cr

@@ -1,4 +1,5 @@
 require "kemal"
+require "kemal-session"
 require "./library"
 require "./handlers/*"
 require "./util"
@@ -65,6 +66,13 @@ class Server
       serve_static false
       add_handler StaticHandler.new
     {% end %}
+
+    Kemal::Session.config do |c|
+      c.timeout = 365.days
+      c.secret = Config.current.session_secret
+      c.cookie_name = "mango-sessid-#{Config.current.port}"
+      c.path = Config.current.base_url
+    end
   end
 
   def start

src/util.cr

@@ -6,12 +6,9 @@ UPLOAD_URL_PREFIX = "/uploads"
 macro layout(name)
   base_url = Config.current.base_url
   begin
-    cookie = env.request.cookies.find do |c|
-      c.name == "token-#{Config.current.port}"
-    end
     is_admin = false
-    unless cookie.nil?
-      is_admin = @context.storage.verify_admin cookie.value
+    if token = env.session.string? "token"
+      is_admin = @context.storage.verify_admin token
     end
     render "src/views/#{{{name}}}.ecr", "src/views/layout.ecr"
   rescue e
@@ -28,10 +25,8 @@ end
 macro get_username(env)
   # if the request gets here, it has gone through the auth handler, and
   #   we can be sure that a valid token exists, so we can use not_nil! here
-  cookie = {{env}}.request.cookies.find do |c|
-    c.name == "token-#{Config.current.port}"
-  end.not_nil!
-  (@context.storage.verify_token cookie.value).not_nil!
+  token = env.session.string "token"
+  (@context.storage.verify_token token).not_nil!
 end
 
 def send_json(env, json)
@@ -137,13 +132,6 @@ macro render_xml(path)
   send_file env, ECR.render({{path}}).to_slice, "application/xml"
 end
 
-def set_token_cookie(env, token)
-  cookie = HTTP::Cookie.new "token-#{Config.current.port}", token
-  cookie.path = Config.current.base_url
-  cookie.expires = Time.local.shift years: 1
-  env.response.cookies << cookie
-end
-
 macro render_component(filename)
   render "src/views/components/#{{{filename}}}.ecr"
 end