Remove the rate limit for the forward auth system

Dockerfile

@@ -11,6 +11,8 @@
 ARG RUBY_VERSION=3.4.6
 FROM docker.io/library/ruby:$RUBY_VERSION-slim AS base
 
+LABEL org.opencontainers.image.source=https://github.com/dkam/clinch
+
 # Rails app lives here
 WORKDIR /rails
 

Gemfile

@@ -35,11 +35,11 @@ gem "jwt", "~> 3.1"
 gem "webauthn", "~> 3.0"
 
 # Public Suffix List for domain parsing
-gem "public_suffix", "~> 6.0"
+gem "public_suffix", "~> 7.0"
 
 # Error tracking and performance monitoring (optional, configured via SENTRY_DSN)
-gem "sentry-ruby", "~> 5.18"
-gem "sentry-rails", "~> 5.18"
+gem "sentry-ruby", "~> 6.2"
+gem "sentry-rails", "~> 6.2"
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
 gem "tzinfo-data", platforms: %i[ windows jruby ]

Gemfile.lock

@@ -75,8 +75,8 @@ GEM
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
-    addressable (2.8.7)
-      public_suffix (>= 2.0.2, < 7.0)
+    addressable (2.8.8)
+      public_suffix (>= 2.0.2, < 8.0)
     android_key_attestation (0.3.0)
     ast (2.4.3)
     base64 (0.3.0)
@@ -85,13 +85,13 @@ GEM
     bigdecimal (3.3.1)
     bindata (2.5.1)
     bindex (0.8.1)
-    bootsnap (1.18.6)
+    bootsnap (1.19.0)
       msgpack (~> 1.2)
-    brakeman (7.1.0)
+    brakeman (7.1.1)
       racc
     builder (3.3.0)
-    bundler-audit (0.9.2)
-      bundler (>= 1.2.0, < 3)
+    bundler-audit (0.9.3)
+      bundler (>= 1.2.0)
       thor (~> 1.0)
     capybara (3.40.0)
       addressable
@@ -107,7 +107,7 @@ GEM
       logger (~> 1.5)
     chunky_png (1.4.0)
     concurrent-ruby (1.3.5)
-    connection_pool (2.5.4)
+    connection_pool (2.5.5)
     cose (1.3.1)
       cbor (~> 0.5.9)
       openssl-signature_algorithm (~> 1.0)
@@ -119,7 +119,7 @@ GEM
     dotenv (3.1.8)
     drb (2.2.3)
     ed25519 (1.4.0)
-    erb (5.1.3)
+    erb (6.0.0)
     erubi (1.13.1)
     ffi (1.17.2-aarch64-linux-gnu)
     ffi (1.17.2-aarch64-linux-musl)
@@ -147,10 +147,10 @@ GEM
     jbuilder (2.14.1)
       actionview (>= 7.0.0)
       activesupport (>= 7.0.0)
-    json (2.15.2)
+    json (2.16.0)
     jwt (3.1.2)
       base64
-    kamal (2.8.1)
+    kamal (2.9.0)
       activesupport (>= 7.0)
       base64 (~> 0.2)
       bcrypt_pbkdf (~> 1.0)
@@ -184,7 +184,7 @@ GEM
     mini_magick (5.3.1)
       logger
     mini_mime (1.1.5)
-    minitest (5.26.0)
+    minitest (5.26.2)
     msgpack (1.8.0)
     net-imap (0.5.12)
       date
@@ -220,7 +220,7 @@ GEM
       openssl (> 2.0)
     ostruct (0.6.3)
     parallel (1.27.0)
-    parser (3.3.9.0)
+    parser (3.3.10.0)
       ast (~> 2.4.1)
       racc
     pp (0.6.3)
@@ -234,7 +234,7 @@ GEM
     psych (5.2.6)
       date
       stringio
-    public_suffix (6.0.2)
+    public_suffix (7.0.0)
     puma (7.1.0)
       nio4r (~> 2.0)
     racc (1.8.1)
@@ -278,20 +278,20 @@ GEM
       zeitwerk (~> 2.6)
     rainbow (3.1.1)
     rake (13.3.1)
-    rdoc (6.15.1)
+    rdoc (6.16.1)
       erb
       psych (>= 4.0.0)
       tsort
     regexp_parser (2.11.3)
-    reline (0.6.2)
+    reline (0.6.3)
       io-console (~> 0.5)
     rexml (3.4.4)
     rotp (6.3.0)
-    rqrcode (3.1.0)
+    rqrcode (3.1.1)
       chunky_png (~> 1.0)
       rqrcode_core (~> 2.0)
-    rqrcode_core (2.0.0)
-    rubocop (1.81.6)
+    rqrcode_core (2.0.1)
+    rubocop (1.81.7)
       json (~> 2.3)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.1.0)
@@ -302,14 +302,14 @@ GEM
       rubocop-ast (>= 1.47.1, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 4.0)
-    rubocop-ast (1.47.1)
+    rubocop-ast (1.48.0)
       parser (>= 3.3.7.2)
       prism (~> 1.4)
     rubocop-performance (1.26.1)
       lint_roller (~> 1.1)
       rubocop (>= 1.75.0, < 2.0)
       rubocop-ast (>= 1.47.1, < 2.0)
-    rubocop-rails (2.33.4)
+    rubocop-rails (2.34.2)
       activesupport (>= 4.2.0)
       lint_roller (~> 1.1)
       rack (>= 1.1)
@@ -323,7 +323,7 @@ GEM
     ruby-vips (2.2.5)
       ffi (~> 1.12)
       logger
-    rubyzip (3.2.1)
+    rubyzip (3.2.2)
     safety_net_attestation (0.5.0)
       jwt (>= 2.0, < 4.0)
     securerandom (0.4.1)
@@ -333,10 +333,10 @@ GEM
       rexml (~> 3.2, >= 3.2.5)
       rubyzip (>= 1.2.2, < 4.0)
       websocket (~> 1.0)
-    sentry-rails (5.28.0)
-      railties (>= 5.0)
-      sentry-ruby (~> 5.28.0)
-    sentry-ruby (5.28.0)
+    sentry-rails (6.2.0)
+      railties (>= 5.2.0)
+      sentry-ruby (~> 6.2.0)
+    sentry-ruby (6.2.0)
       bigdecimal
       concurrent-ruby (~> 1.0, >= 1.0.2)
     solid_cable (3.0.12)
@@ -344,17 +344,17 @@ GEM
       activejob (>= 7.2)
       activerecord (>= 7.2)
       railties (>= 7.2)
-    solid_cache (1.0.8)
+    solid_cache (1.0.10)
       activejob (>= 7.2)
       activerecord (>= 7.2)
       railties (>= 7.2)
-    sqlite3 (2.7.4-aarch64-linux-gnu)
-    sqlite3 (2.7.4-aarch64-linux-musl)
-    sqlite3 (2.7.4-arm-linux-gnu)
-    sqlite3 (2.7.4-arm-linux-musl)
-    sqlite3 (2.7.4-arm64-darwin)
-    sqlite3 (2.7.4-x86_64-linux-gnu)
-    sqlite3 (2.7.4-x86_64-linux-musl)
+    sqlite3 (2.8.1-aarch64-linux-gnu)
+    sqlite3 (2.8.1-aarch64-linux-musl)
+    sqlite3 (2.8.1-arm-linux-gnu)
+    sqlite3 (2.8.1-arm-linux-musl)
+    sqlite3 (2.8.1-arm64-darwin)
+    sqlite3 (2.8.1-x86_64-linux-gnu)
+    sqlite3 (2.8.1-x86_64-linux-musl)
     sshkit (1.24.0)
       base64
       logger
@@ -364,16 +364,16 @@ GEM
       ostruct
     stimulus-rails (1.3.4)
       railties (>= 6.0.0)
-    stringio (3.1.7)
-    tailwindcss-rails (4.3.0)
+    stringio (3.1.8)
+    tailwindcss-rails (4.4.0)
       railties (>= 7.0.0)
       tailwindcss-ruby (~> 4.0)
-    tailwindcss-ruby (4.1.13)
-    tailwindcss-ruby (4.1.13-aarch64-linux-gnu)
-    tailwindcss-ruby (4.1.13-aarch64-linux-musl)
-    tailwindcss-ruby (4.1.13-arm64-darwin)
-    tailwindcss-ruby (4.1.13-x86_64-linux-gnu)
-    tailwindcss-ruby (4.1.13-x86_64-linux-musl)
+    tailwindcss-ruby (4.1.16)
+    tailwindcss-ruby (4.1.16-aarch64-linux-gnu)
+    tailwindcss-ruby (4.1.16-aarch64-linux-musl)
+    tailwindcss-ruby (4.1.16-arm64-darwin)
+    tailwindcss-ruby (4.1.16-x86_64-linux-gnu)
+    tailwindcss-ruby (4.1.16-x86_64-linux-musl)
     thor (1.4.0)
     thruster (0.1.16)
     thruster (0.1.16-aarch64-linux)
@@ -385,7 +385,7 @@ GEM
       openssl (> 2.0)
       openssl-signature_algorithm (~> 1.0)
     tsort (0.2.0)
-    turbo-rails (2.0.17)
+    turbo-rails (2.0.20)
       actionpack (>= 7.1.0)
       railties (>= 7.1.0)
     tzinfo (2.0.6)
@@ -393,7 +393,7 @@ GEM
     unicode-display_width (3.2.0)
       unicode-emoji (~> 4.1)
     unicode-emoji (4.1.0)
-    uri (1.1.0)
+    uri (1.1.1)
     useragent (0.16.11)
     web-console (4.2.1)
       actionview (>= 6.0.0)
@@ -442,15 +442,15 @@ DEPENDENCIES
   kamal
   letter_opener
   propshaft
-  public_suffix (~> 6.0)
+  public_suffix (~> 7.0)
   puma (>= 5.0)
   rails (~> 8.1.1)
   rotp (~> 6.3)
   rqrcode (~> 3.1)
   rubocop-rails-omakase
   selenium-webdriver
-  sentry-rails (~> 5.18)
-  sentry-ruby (~> 5.18)
+  sentry-rails (~> 6.2)
+  sentry-ruby (~> 6.2)
   solid_cable
   solid_cache
   sqlite3 (>= 2.1)

README.md

@@ -15,10 +15,12 @@ I've completed all planned features:
 * Forward Auth configured and working
 * OIDC provider with auto discovery, refresh tokens, and token revocation
 * Configurable token expiry per application (access, refresh, ID tokens)
+* Backchannel Logout
+* Per-application logout / revoke
 * Invite users by email, assign to groups
 * Self managed password reset by email
 * Use Groups to assign Applications ( Family group can access Kavita, Developers can access Gitea )
-* Configurable Group and User custom claims for OIDC token
+* Configurable Group, User & App+User custom claims for OIDC token
 * Display all Applications available to the user on their Dashboard
 * Display all logged in sessions and OIDC logged in sessions
 
@@ -94,6 +96,7 @@ Standard OAuth2/OIDC provider with endpoints:
 
 Features:
 - **Refresh tokens** - Long-lived tokens (30 days default) with automatic rotation and revocation
+- **Token family tracking** - Advanced security detects token replay attacks and revokes compromised token families
 - **Configurable token expiry** - Set access token (5min-24hr), refresh token (1-90 days), and ID token TTL per application
 - **Token security** - BCrypt-hashed tokens, automatic cleanup of expired tokens
 - **Pairwise subject identifiers** - Each user gets a unique, stable `sub` claim per application for enhanced privacy
@@ -122,10 +125,54 @@ Send emails for:
 - **Session revocation** - Users and admins can revoke individual sessions
 
 ### Access Control
-- **Group-based allowlists** - Restrict applications to specific user groups
-- **Per-application access** - Each app defines which groups can access it
-- **Automatic enforcement** - Access checks during OIDC authorization and ForwardAuth
-- **Custom claims** - Add arbitrary claims to OIDC tokens via groups and users (perfect for app-specific roles)
+
+#### Group-Based Application Access
+Clinch uses groups to control which users can access which applications:
+
+- **Create groups** - Organize users into logical groups (readers, editors, family, developers, etc.)
+- **Assign groups to applications** - Each app defines which groups are allowed to access it
+  - Example: Kavita app allows the "readers" group → only users in the "readers" group can sign in
+  - If no groups are assigned to an app → all active users can access it
+- **Automatic enforcement** - Access checks happen automatically:
+  - During OIDC authorization flow (before consent)
+  - During ForwardAuth verification (before proxying requests)
+  - Users not in allowed groups receive a "You do not have permission" error
+
+#### Group Claims in Tokens
+- **OIDC tokens include group membership** - ID tokens contain a `groups` claim with all user's groups
+- **Custom claims** - Add arbitrary key-value pairs to tokens via groups and users
+  - Group claims apply to all members (e.g., `{"role": "viewer"}`)
+  - User claims override group claims for fine-grained control
+  - Perfect for app-specific authorization (e.g., admin vs. read-only roles)
+
+#### Custom Claims Merging
+Custom claims from groups and users are merged into OIDC ID tokens with the following precedence:
+
+1. **Default OIDC claims** - Standard claims (`iss`, `sub`, `aud`, `exp`, `email`, etc.)
+2. **Standard Clinch claims** - `groups` array (list of user's group names)
+3. **Group custom claims** - Merged in order; later groups override earlier ones
+4. **User custom claims** - Override all group claims
+5. **Application-specific claims** - Highest priority; override all other claims
+
+**Example:**
+- Group "readers" has `{"role": "viewer", "max_items": 10}`
+- Group "premium" has `{"role": "subscriber", "max_items": 100}`
+- User (in both groups) has `{"max_items": 500}`
+- **Result:** `{"role": "subscriber", "max_items": 500}` (user overrides max_items, premium overrides role)
+
+#### Application-Specific Claims
+Configure different claims for different applications on a per-user basis:
+
+- **Per-app customization** - Each application can have unique claims for each user
+- **Highest precedence** - App-specific claims override group and user global claims
+- **Use case** - Different roles in different apps (e.g., admin in Kavita, user in Audiobookshelf)
+- **Admin UI** - Configure via Admin → Users → Edit User → App-Specific Claim Overrides
+
+**Example:**
+- User Alice, global claims: `{"theme": "dark"}`
+- Kavita app-specific: `{"kavita_groups": ["admin"]}`
+- Audiobookshelf app-specific: `{"abs_groups": ["user"]}`
+- **Result:** Kavita receives `{"theme": "dark", "kavita_groups": ["admin"]}`, Audiobookshelf receives `{"theme": "dark", "abs_groups": ["user"]}`
 
 ---
 

VERSION

@@ -1 +0,0 @@
-2025.02

app/controllers/active_sessions_controller.rb

@@ -16,16 +16,82 @@ class ActiveSessionsController < ApplicationController
       return
     end
 
+    # Send backchannel logout notification before revoking consent
+    if application.supports_backchannel_logout?
+      BackchannelLogoutJob.perform_later(
+        user_id: @user.id,
+        application_id: application.id,
+        consent_sid: consent.sid
+      )
+      Rails.logger.info "ActiveSessionsController: Enqueued backchannel logout for #{application.name}"
+    end
+
+    # Revoke all tokens for this user-application pair
+    now = Time.current
+    revoked_access_tokens = OidcAccessToken.where(application: application, user: @user, revoked_at: nil)
+                                           .update_all(revoked_at: now)
+    revoked_refresh_tokens = OidcRefreshToken.where(application: application, user: @user, revoked_at: nil)
+                                             .update_all(revoked_at: now)
+
+    Rails.logger.info "ActiveSessionsController: Revoked #{revoked_access_tokens} access tokens and #{revoked_refresh_tokens} refresh tokens for #{application.name}"
+
     # Revoke the consent
     consent.destroy
     redirect_to active_sessions_path, notice: "Successfully revoked access to #{application.name}."
   end
 
+  def logout_from_app
+    @user = Current.session.user
+    application = Application.find(params[:application_id])
+
+    # Check if user has consent for this application
+    consent = @user.oidc_user_consents.find_by(application: application)
+    unless consent
+      redirect_to root_path, alert: "No active session found for this application."
+      return
+    end
+
+    # Send backchannel logout notification
+    if application.supports_backchannel_logout?
+      BackchannelLogoutJob.perform_later(
+        user_id: @user.id,
+        application_id: application.id,
+        consent_sid: consent.sid
+      )
+      Rails.logger.info "ActiveSessionsController: Enqueued backchannel logout for #{application.name}"
+    end
+
+    # Revoke all tokens for this user-application pair
+    now = Time.current
+    revoked_access_tokens = OidcAccessToken.where(application: application, user: @user, revoked_at: nil)
+                                           .update_all(revoked_at: now)
+    revoked_refresh_tokens = OidcRefreshToken.where(application: application, user: @user, revoked_at: nil)
+                                             .update_all(revoked_at: now)
+
+    Rails.logger.info "ActiveSessionsController: Logged out from #{application.name} - revoked #{revoked_access_tokens} access tokens and #{revoked_refresh_tokens} refresh tokens"
+
+    # Keep the consent intact - this is the key difference from revoke_consent
+    redirect_to root_path, notice: "Successfully logged out of #{application.name}."
+  end
+
   def revoke_all_consents
     @user = Current.session.user
-    count = @user.oidc_user_consents.count
+    consents = @user.oidc_user_consents.includes(:application)
+    count = consents.count
 
     if count > 0
+      # Send backchannel logout notifications before revoking consents
+      consents.each do |consent|
+        next unless consent.application.supports_backchannel_logout?
+
+        BackchannelLogoutJob.perform_later(
+          user_id: @user.id,
+          application_id: consent.application.id,
+          consent_sid: consent.sid
+        )
+      end
+      Rails.logger.info "ActiveSessionsController: Enqueued #{count} backchannel logout notifications"
+
       @user.oidc_user_consents.destroy_all
       redirect_to active_sessions_path, notice: "Successfully revoked access to #{count} applications."
     else

app/controllers/admin/applications_controller.rb

@@ -100,6 +100,7 @@ module Admin
       params.require(:application).permit(
         :name, :slug, :app_type, :active, :redirect_uris, :description, :metadata,
         :domain_pattern, :landing_url, :access_token_ttl, :refresh_token_ttl, :id_token_ttl,
+        :icon, :backchannel_logout_uri,
         headers_config: {}
       ).tap do |whitelisted|
         # Remove client_secret from params if present (shouldn't be updated via form)

app/controllers/admin/groups_controller.rb

@@ -18,7 +18,25 @@ module Admin
     end
 
     def create
-      @group = Group.new(group_params)
+      create_params = group_params
+
+      # Parse custom_claims JSON if provided
+      if create_params[:custom_claims].present?
+        begin
+          create_params[:custom_claims] = JSON.parse(create_params[:custom_claims])
+        rescue JSON::ParserError
+          @group = Group.new
+          @group.errors.add(:custom_claims, "must be valid JSON")
+          @available_users = User.order(:email_address)
+          render :new, status: :unprocessable_entity
+          return
+        end
+      else
+        # If empty or blank, set to empty hash (NOT NULL constraint)
+        create_params[:custom_claims] = {}
+      end
+
+      @group = Group.new(create_params)
 
       if @group.save
         # Handle user assignments
@@ -39,7 +57,24 @@ module Admin
     end
 
     def update
-      if @group.update(group_params)
+      update_params = group_params
+
+      # Parse custom_claims JSON if provided
+      if update_params[:custom_claims].present?
+        begin
+          update_params[:custom_claims] = JSON.parse(update_params[:custom_claims])
+        rescue JSON::ParserError
+          @group.errors.add(:custom_claims, "must be valid JSON")
+          @available_users = User.order(:email_address)
+          render :edit, status: :unprocessable_entity
+          return
+        end
+      else
+        # If empty or blank, set to empty hash (NOT NULL constraint)
+        update_params[:custom_claims] = {}
+      end
+
+      if @group.update(update_params)
         # Handle user assignments
         if params[:group][:user_ids].present?
           user_ids = params[:group][:user_ids].reject(&:blank?)
@@ -67,7 +102,7 @@ module Admin
     end
 
     def group_params
-      params.require(:group).permit(:name, :description, custom_claims: {})
+      params.require(:group).permit(:name, :description, :custom_claims)
     end
   end
 end

app/controllers/admin/users_controller.rb

@@ -1,6 +1,6 @@
 module Admin
   class UsersController < BaseController
-    before_action :set_user, only: [:show, :edit, :update, :destroy, :resend_invitation]
+    before_action :set_user, only: [:show, :edit, :update, :destroy, :resend_invitation, :update_application_claims, :delete_application_claims]
 
     def index
       @users = User.order(created_at: :desc)
@@ -27,6 +27,7 @@ module Admin
     end
 
     def edit
+      @applications = Application.active.order(:name)
     end
 
     def update
@@ -35,9 +36,25 @@ module Admin
       # Only update password if provided
       update_params.delete(:password) if update_params[:password].blank?
 
+      # Parse custom_claims JSON if provided
+      if update_params[:custom_claims].present?
+        begin
+          update_params[:custom_claims] = JSON.parse(update_params[:custom_claims])
+        rescue JSON::ParserError
+          @user.errors.add(:custom_claims, "must be valid JSON")
+          @applications = Application.active.order(:name)
+          render :edit, status: :unprocessable_entity
+          return
+        end
+      else
+        # If empty or blank, set to empty hash (NOT NULL constraint)
+        update_params[:custom_claims] = {}
+      end
+
       if @user.update(update_params)
         redirect_to admin_users_path, notice: "User updated successfully."
       else
+        @applications = Application.active.order(:name)
         render :edit, status: :unprocessable_entity
       end
     end
@@ -63,6 +80,41 @@ module Admin
       redirect_to admin_users_path, notice: "User deleted successfully."
     end
 
+    # POST /admin/users/:id/update_application_claims
+    def update_application_claims
+      application = Application.find(params[:application_id])
+
+      claims_json = params[:custom_claims].presence || "{}"
+      begin
+        claims = JSON.parse(claims_json)
+      rescue JSON::ParserError
+        redirect_to edit_admin_user_path(@user), alert: "Invalid JSON format for claims."
+        return
+      end
+
+      app_claim = @user.application_user_claims.find_or_initialize_by(application: application)
+      app_claim.custom_claims = claims
+
+      if app_claim.save
+        redirect_to edit_admin_user_path(@user), notice: "App-specific claims updated for #{application.name}."
+      else
+        error_message = app_claim.errors.full_messages.join(", ")
+        redirect_to edit_admin_user_path(@user), alert: "Failed to update claims: #{error_message}"
+      end
+    end
+
+    # DELETE /admin/users/:id/delete_application_claims
+    def delete_application_claims
+      application = Application.find(params[:application_id])
+      app_claim = @user.application_user_claims.find_by(application: application)
+
+      if app_claim&.destroy
+        redirect_to edit_admin_user_path(@user), notice: "App-specific claims removed for #{application.name}."
+      else
+        redirect_to edit_admin_user_path(@user), alert: "No claims found to remove."
+      end
+    end
+
     private
 
     def set_user
@@ -71,7 +123,7 @@ module Admin
 
     def user_params
       # Base attributes that all admins can modify
-      base_params = params.require(:user).permit(:email_address, :name, :password, :status, :totp_required, custom_claims: {})
+      base_params = params.require(:user).permit(:email_address, :username, :name, :password, :status, :totp_required, :custom_claims)
 
       # Only allow modifying admin status when editing other users (prevent self-demotion)
       if params[:id] != Current.session.user.id.to_s

app/controllers/api/forward_auth_controller.rb

@@ -3,7 +3,7 @@ module Api
     # ForwardAuth endpoints need session storage for return URL
     allow_unauthenticated_access
     skip_before_action :verify_authenticity_token
-    rate_limit to: 100, within: 1.minute, only: :verify, with: -> { head :too_many_requests }
+    # No rate limiting on forward_auth endpoint - proxy middleware hits this frequently
 
     # GET /api/verify
     # This endpoint is called by reverse proxies (Traefik, Caddy, nginx)

app/controllers/oidc_controller.rb

@@ -20,10 +20,12 @@ class OidcController < ApplicationController
       grant_types_supported: ["authorization_code", "refresh_token"],
       subject_types_supported: ["public"],
       id_token_signing_alg_values_supported: ["RS256"],
-      scopes_supported: ["openid", "profile", "email", "groups"],
+      scopes_supported: ["openid", "profile", "email", "groups", "offline_access"],
       token_endpoint_auth_methods_supported: ["client_secret_post", "client_secret_basic"],
       claims_supported: ["sub", "email", "email_verified", "name", "preferred_username", "groups", "admin"],
-      code_challenge_methods_supported: ["plain", "S256"]
+      code_challenge_methods_supported: ["plain", "S256"],
+      backchannel_logout_supported: true,
+      backchannel_logout_session_supported: true
     }
 
     render json: config
@@ -534,9 +536,6 @@ class OidcController < ApplicationController
       claims[:groups] = user.groups.pluck(:name)
     end
 
-    # Add admin claim if user is admin
-    claims[:admin] = true if user.admin?
-
     # Merge custom claims from groups
     user.groups.each do |group|
       claims.merge!(group.parsed_custom_claims)
@@ -545,6 +544,10 @@ class OidcController < ApplicationController
     # Merge custom claims from user (overrides group claims)
     claims.merge!(user.parsed_custom_claims)
 
+    # Merge app-specific custom claims (highest priority)
+    application = access_token.application
+    claims.merge!(application.custom_claims_for_user(user))
+
     render json: claims
   end
 
@@ -626,6 +629,11 @@ class OidcController < ApplicationController
 
     # If user is authenticated, log them out
     if authenticated?
+      user = Current.session.user
+
+      # Send backchannel logout notifications to all connected applications
+      send_backchannel_logout_notifications(user)
+
       # Invalidate the current session
       Current.session&.destroy
       reset_session
@@ -765,4 +773,26 @@ class OidcController < ApplicationController
       false
     end
   end
+
+  def send_backchannel_logout_notifications(user)
+    # Find all active OIDC consents for this user
+    consents = OidcUserConsent.where(user: user).includes(:application)
+
+    consents.each do |consent|
+      # Skip if application doesn't support backchannel logout
+      next unless consent.application.supports_backchannel_logout?
+
+      # Enqueue background job to send logout notification
+      BackchannelLogoutJob.perform_later(
+        user_id: user.id,
+        application_id: consent.application.id,
+        consent_sid: consent.sid
+      )
+    end
+
+    Rails.logger.info "OidcController: Enqueued #{consents.count} backchannel logout notifications for user #{user.id}"
+  rescue => e
+    # Log error but don't block logout
+    Rails.logger.error "OidcController: Failed to enqueue backchannel logout: #{e.class} - #{e.message}"
+  end
 end

app/controllers/passwords_controller.rb

@@ -11,7 +11,7 @@ class PasswordsController < ApplicationController
       PasswordsMailer.reset(user).deliver_later
     end
 
-    redirect_to new_session_path, notice: "Password reset instructions sent (if user with that email address exists)."
+    redirect_to signin_path, notice: "Password reset instructions sent (if user with that email address exists)."
   end
 
   def edit
@@ -20,7 +20,7 @@ class PasswordsController < ApplicationController
   def update
     if @user.update(params.permit(:password, :password_confirmation))
       @user.sessions.destroy_all
-      redirect_to new_session_path, notice: "Password has been reset."
+      redirect_to signin_path, notice: "Password has been reset."
     else
       redirect_to edit_password_path(params[:token]), alert: "Passwords did not match."
     end
@@ -29,6 +29,7 @@ class PasswordsController < ApplicationController
   private
     def set_user_by_token
       @user = User.find_by_token_for(:password_reset, params[:token])
+      redirect_to new_password_path, alert: "Password reset link is invalid or has expired." if @user.nil?
     rescue ActiveSupport::MessageVerifier::InvalidSignature
       redirect_to new_password_path, alert: "Password reset link is invalid or has expired."
     end

app/controllers/sessions_controller.rb

@@ -134,6 +134,12 @@ class SessionsController < ApplicationController
   end
 
   def destroy
+    # Send backchannel logout notifications before terminating session
+    if authenticated?
+      user = Current.session.user
+      send_backchannel_logout_notifications(user)
+    end
+
     terminate_session
     redirect_to signin_path, status: :see_other, notice: "Signed out successfully."
   end
@@ -311,4 +317,26 @@ class SessionsController < ApplicationController
       nil
     end
   end
+
+  def send_backchannel_logout_notifications(user)
+    # Find all active OIDC consents for this user
+    consents = OidcUserConsent.where(user: user).includes(:application)
+
+    consents.each do |consent|
+      # Skip if application doesn't support backchannel logout
+      next unless consent.application.supports_backchannel_logout?
+
+      # Enqueue background job to send logout notification
+      BackchannelLogoutJob.perform_later(
+        user_id: user.id,
+        application_id: consent.application.id,
+        consent_sid: consent.sid
+      )
+    end
+
+    Rails.logger.info "SessionsController: Enqueued #{consents.count} backchannel logout notifications for user #{user.id}"
+  rescue => e
+    # Log error but don't block logout
+    Rails.logger.error "SessionsController: Failed to enqueue backchannel logout: #{e.class} - #{e.message}"
+  end
 end

app/helpers/claims_helper.rb

@@ -0,0 +1,69 @@
+module ClaimsHelper
+  include ClaimsMerger
+
+  # Preview final merged claims for a user accessing an application
+  def preview_user_claims(user, application)
+    claims = {
+      # Standard OIDC claims
+      email: user.email_address,
+      email_verified: true,
+      preferred_username: user.username.presence || user.email_address,
+      name: user.name.presence || user.email_address
+    }
+
+    # Add groups
+    if user.groups.any?
+      claims[:groups] = user.groups.pluck(:name)
+    end
+
+    # Merge group custom claims (arrays are combined, not overwritten)
+    user.groups.each do |group|
+      claims = deep_merge_claims(claims, group.parsed_custom_claims)
+    end
+
+    # Merge user custom claims (arrays are combined, other values override)
+    claims = deep_merge_claims(claims, user.parsed_custom_claims)
+
+    # Merge app-specific claims (arrays are combined)
+    claims = deep_merge_claims(claims, application.custom_claims_for_user(user))
+
+    claims
+  end
+
+  # Get claim sources breakdown for display
+  def claim_sources(user, application)
+    sources = []
+
+    # Group claims
+    user.groups.each do |group|
+      if group.parsed_custom_claims.any?
+        sources << {
+          type: :group,
+          name: group.name,
+          claims: group.parsed_custom_claims
+        }
+      end
+    end
+
+    # User claims
+    if user.parsed_custom_claims.any?
+      sources << {
+        type: :user,
+        name: "User Override",
+        claims: user.parsed_custom_claims
+      }
+    end
+
+    # App-specific claims
+    app_claims = application.custom_claims_for_user(user)
+    if app_claims.any?
+      sources << {
+        type: :application,
+        name: "App-Specific (#{application.name})",
+        claims: app_claims
+      }
+    end
+
+    sources
+  end
+end

app/javascript/controllers/file_drop_controller.js

@@ -0,0 +1,96 @@
+import { Controller } from "@hotwired/stimulus"
+
+export default class extends Controller {
+  static targets = ["input", "dropzone", "preview", "previewImage", "filename", "filesize"]
+
+  connect() {
+    // Prevent default drag behaviors on the whole document
+    ["dragenter", "dragover", "dragleave", "drop"].forEach(eventName => {
+      document.body.addEventListener(eventName, this.preventDefaults, false)
+    })
+  }
+
+  disconnect() {
+    ["dragenter", "dragover", "dragleave", "drop"].forEach(eventName => {
+      document.body.removeEventListener(eventName, this.preventDefaults, false)
+    })
+  }
+
+  preventDefaults(e) {
+    e.preventDefault()
+    e.stopPropagation()
+  }
+
+  dragover(e) {
+    e.preventDefault()
+    e.stopPropagation()
+    this.dropzoneTarget.classList.add("border-blue-500", "bg-blue-50")
+  }
+
+  dragleave(e) {
+    e.preventDefault()
+    e.stopPropagation()
+    this.dropzoneTarget.classList.remove("border-blue-500", "bg-blue-50")
+  }
+
+  drop(e) {
+    e.preventDefault()
+    e.stopPropagation()
+    this.dropzoneTarget.classList.remove("border-blue-500", "bg-blue-50")
+
+    const files = e.dataTransfer.files
+    if (files.length > 0) {
+      // Set the file to the input element
+      this.inputTarget.files = files
+      this.handleFiles()
+    }
+  }
+
+  handleFiles() {
+    const file = this.inputTarget.files[0]
+    if (!file) return
+
+    // Validate file type
+    const validTypes = ["image/png", "image/jpg", "image/jpeg", "image/gif", "image/svg+xml"]
+    if (!validTypes.includes(file.type)) {
+      alert("Please upload a PNG, JPG, GIF, or SVG image")
+      this.clear()
+      return
+    }
+
+    // Validate file size (2MB)
+    if (file.size > 2 * 1024 * 1024) {
+      alert("File size must be less than 2MB")
+      this.clear()
+      return
+    }
+
+    // Show preview
+    this.filenameTarget.textContent = file.name
+    this.filesizeTarget.textContent = this.formatFileSize(file.size)
+
+    // Create preview image
+    const reader = new FileReader()
+    reader.onload = (e) => {
+      this.previewImageTarget.src = e.target.result
+      this.previewTarget.classList.remove("hidden")
+    }
+    reader.readAsDataURL(file)
+  }
+
+  clear(e) {
+    if (e) {
+      e.preventDefault()
+    }
+    this.inputTarget.value = ""
+    this.previewTarget.classList.add("hidden")
+  }
+
+  formatFileSize(bytes) {
+    if (bytes === 0) return "0 Bytes"
+    const k = 1024
+    const sizes = ["Bytes", "KB", "MB"]
+    const i = Math.floor(Math.log(bytes) / Math.log(k))
+    return Math.round(bytes / Math.pow(k, i) * 100) / 100 + " " + sizes[i]
+  }
+}

app/jobs/backchannel_logout_job.rb

@@ -0,0 +1,52 @@
+class BackchannelLogoutJob < ApplicationJob
+  queue_as :default
+
+  # Retry with exponential backoff: 1s, 5s, 25s
+  retry_on StandardError, wait: :exponentially_longer, attempts: 3
+
+  def perform(user_id:, application_id:, consent_sid:)
+    # Find the records
+    user = User.find_by(id: user_id)
+    application = Application.find_by(id: application_id)
+    consent = OidcUserConsent.find_by(sid: consent_sid)
+
+    # Validate we have all required data
+    unless user && application && consent
+      Rails.logger.warn "BackchannelLogout: Missing data - user: #{user.present?}, app: #{application.present?}, consent: #{consent.present?}"
+      return
+    end
+
+    # Skip if application doesn't support backchannel logout
+    unless application.supports_backchannel_logout?
+      Rails.logger.debug "BackchannelLogout: Application #{application.name} doesn't support backchannel logout"
+      return
+    end
+
+    # Generate the logout token
+    logout_token = OidcJwtService.generate_logout_token(user, application, consent)
+
+    # Send HTTP POST to the application's backchannel logout URI
+    uri = URI.parse(application.backchannel_logout_uri)
+
+    begin
+      response = Net::HTTP.start(uri.host, uri.port, use_ssl: uri.scheme == 'https', open_timeout: 5, read_timeout: 5) do |http|
+        request = Net::HTTP::Post.new(uri.path.presence || '/')
+        request['Content-Type'] = 'application/x-www-form-urlencoded'
+        request.set_form_data({ logout_token: logout_token })
+        http.request(request)
+      end
+
+      if response.code.to_i == 200
+        Rails.logger.info "BackchannelLogout: Successfully sent logout notification to #{application.name} (#{application.backchannel_logout_uri})"
+      else
+        Rails.logger.warn "BackchannelLogout: Application #{application.name} returned HTTP #{response.code} from #{application.backchannel_logout_uri}"
+      end
+    rescue Net::OpenTimeout, Net::ReadTimeout => e
+      Rails.logger.warn "BackchannelLogout: Timeout sending logout to #{application.name} (#{application.backchannel_logout_uri}): #{e.message}"
+      raise # Retry on timeout
+    rescue StandardError => e
+      Rails.logger.error "BackchannelLogout: Failed to send logout to #{application.name} (#{application.backchannel_logout_uri}): #{e.class} - #{e.message}"
+      raise # Retry on error
+    end
+  end
+end

app/models/application.rb

@@ -1,8 +1,14 @@
 class Application < ApplicationRecord
   has_secure_password :client_secret, validations: false
 
+  has_one_attached :icon
+
+  # Fix SVG content type after attachment
+  after_save :fix_icon_content_type, if: -> { icon.attached? && saved_change_to_attribute?(:id) == false }
+
   has_many :application_groups, dependent: :destroy
   has_many :allowed_groups, through: :application_groups, source: :group
+  has_many :application_user_claims, dependent: :destroy
   has_many :oidc_authorization_codes, dependent: :destroy
   has_many :oidc_access_tokens, dependent: :destroy
   has_many :oidc_refresh_tokens, dependent: :destroy
@@ -17,6 +23,15 @@ class Application < ApplicationRecord
   validates :client_secret, presence: true, on: :create, if: -> { oidc? }
   validates :domain_pattern, presence: true, uniqueness: { case_sensitive: false }, if: :forward_auth?
   validates :landing_url, format: { with: URI::regexp(%w[http https]), allow_nil: true, message: "must be a valid URL" }
+  validates :backchannel_logout_uri, format: {
+    with: URI::regexp(%w[http https]),
+    allow_nil: true,
+    message: "must be a valid HTTP or HTTPS URL"
+  }
+  validate :backchannel_logout_uri_must_be_https_in_production, if: -> { backchannel_logout_uri.present? }
+
+  # Icon validation using ActiveStorage validators
+  validate :icon_validation, if: -> { icon.attached? }
 
   # Token TTL validations (for OIDC apps)
   validates :access_token_ttl, numericality: { greater_than_or_equal_to: 300, less_than_or_equal_to: 86400 }, if: :oidc?  # 5 min - 24 hours
@@ -28,6 +43,10 @@ class Application < ApplicationRecord
     normalized = pattern&.strip&.downcase
     normalized.blank? ? nil : normalized
   }
+  normalizes :backchannel_logout_uri, with: ->(uri) {
+    normalized = uri&.strip
+    normalized.blank? ? nil : normalized
+  }
 
   before_validation :generate_client_credentials, on: :create, if: :oidc?
 
@@ -186,8 +205,50 @@ class Application < ApplicationRecord
     duration_to_human(id_token_ttl || 3600)
   end
 
+  # Get app-specific custom claims for a user
+  def custom_claims_for_user(user)
+    app_claim = application_user_claims.find_by(user: user)
+    app_claim&.parsed_custom_claims || {}
+  end
+
+  # Check if this application supports backchannel logout
+  def supports_backchannel_logout?
+    backchannel_logout_uri.present?
+  end
+
+  # Check if a user has an active session with this application
+  # (i.e., has valid, non-revoked tokens)
+  def user_has_active_session?(user)
+    oidc_access_tokens.where(user: user).valid.exists? ||
+    oidc_refresh_tokens.where(user: user).valid.exists?
+  end
+
   private
 
+  def fix_icon_content_type
+    return unless icon.attached?
+
+    # Fix SVG content type if it was detected incorrectly
+    if icon.filename.extension == "svg" && icon.content_type == "application/octet-stream"
+      icon.blob.update(content_type: "image/svg+xml")
+    end
+  end
+
+  def icon_validation
+    return unless icon.attached?
+
+    # Check content type
+    allowed_types = ['image/png', 'image/jpg', 'image/jpeg', 'image/gif', 'image/svg+xml']
+    unless allowed_types.include?(icon.content_type)
+      errors.add(:icon, 'must be a PNG, JPG, GIF, or SVG image')
+    end
+
+    # Check file size (2MB limit)
+    if icon.blob.byte_size > 2.megabytes
+      errors.add(:icon, 'must be less than 2MB')
+    end
+  end
+
   def duration_to_human(seconds)
     if seconds < 3600
       "#{seconds / 60} minutes"
@@ -206,4 +267,18 @@ class Application < ApplicationRecord
       self.client_secret = secret
     end
   end
+
+  def backchannel_logout_uri_must_be_https_in_production
+    return unless Rails.env.production?
+    return unless backchannel_logout_uri.present?
+
+    begin
+      uri = URI.parse(backchannel_logout_uri)
+      unless uri.scheme == 'https'
+        errors.add(:backchannel_logout_uri, 'must use HTTPS in production')
+      end
+    rescue URI::InvalidURIError
+      # Let the format validator handle invalid URIs
+    end
+  end
 end

app/models/application_user_claim.rb

@@ -0,0 +1,31 @@
+class ApplicationUserClaim < ApplicationRecord
+  belongs_to :application
+  belongs_to :user
+
+  # Reserved OIDC claim names that should not be overridden
+  RESERVED_CLAIMS = %w[
+    iss sub aud exp iat nbf jti nonce azp
+    email email_verified preferred_username name
+    groups
+  ].freeze
+
+  validates :user_id, uniqueness: { scope: :application_id }
+  validate :no_reserved_claim_names
+
+  # Parse custom_claims JSON field
+  def parsed_custom_claims
+    return {} if custom_claims.blank?
+    custom_claims.is_a?(Hash) ? custom_claims : {}
+  end
+
+  private
+
+  def no_reserved_claim_names
+    return if custom_claims.blank?
+
+    reserved_used = parsed_custom_claims.keys.map(&:to_s) & RESERVED_CLAIMS
+    if reserved_used.any?
+      errors.add(:custom_claims, "cannot override reserved OIDC claims: #{reserved_used.join(', ')}")
+    end
+  end
+end

app/models/group.rb

@@ -4,11 +4,31 @@ class Group < ApplicationRecord
   has_many :application_groups, dependent: :destroy
   has_many :applications, through: :application_groups
 
+  # Reserved OIDC claim names that should not be overridden
+  RESERVED_CLAIMS = %w[
+    iss sub aud exp iat nbf jti nonce azp
+    email email_verified preferred_username name
+    groups
+  ].freeze
+
   validates :name, presence: true, uniqueness: { case_sensitive: false }
   normalizes :name, with: ->(name) { name.strip.downcase }
+  validate :no_reserved_claim_names
 
   # Parse custom_claims JSON field
   def parsed_custom_claims
-    custom_claims || {}
+    return {} if custom_claims.blank?
+    custom_claims.is_a?(Hash) ? custom_claims : {}
+  end
+
+  private
+
+  def no_reserved_claim_names
+    return if custom_claims.blank?
+
+    reserved_used = parsed_custom_claims.keys.map(&:to_s) & RESERVED_CLAIMS
+    if reserved_used.any?
+      errors.add(:custom_claims, "cannot override reserved OIDC claims: #{reserved_used.join(', ')}")
+    end
   end
 end

app/models/user.rb

@@ -3,6 +3,7 @@ class User < ApplicationRecord
   has_many :sessions, dependent: :destroy
   has_many :user_groups, dependent: :destroy
   has_many :groups, through: :user_groups
+  has_many :application_user_claims, dependent: :destroy
   has_many :oidc_user_consents, dependent: :destroy
   has_many :webauthn_credentials, dependent: :destroy
 
@@ -20,10 +21,22 @@ class User < ApplicationRecord
   end
 
   normalizes :email_address, with: ->(e) { e.strip.downcase }
+  normalizes :username, with: ->(u) { u.strip.downcase if u.present? }
+
+  # Reserved OIDC claim names that should not be overridden
+  RESERVED_CLAIMS = %w[
+    iss sub aud exp iat nbf jti nonce azp
+    email email_verified preferred_username name
+    groups
+  ].freeze
 
   validates :email_address, presence: true, uniqueness: { case_sensitive: false },
                            format: { with: URI::MailTo::EMAIL_REGEXP }
+  validates :username, uniqueness: { case_sensitive: false }, allow_nil: true,
+                      format: { with: /\A[a-zA-Z0-9_-]+\z/, message: "can only contain letters, numbers, underscores, and hyphens" },
+                      length: { minimum: 2, maximum: 30 }
   validates :password, length: { minimum: 8 }, allow_nil: true
+  validate :no_reserved_claim_names
 
   # Enum - automatically creates scopes (User.active, User.disabled, etc.)
   enum :status, { active: 0, disabled: 1, pending_invitation: 2 }
@@ -182,11 +195,39 @@ class User < ApplicationRecord
 
   # Parse custom_claims JSON field
   def parsed_custom_claims
-    custom_claims || {}
+    return {} if custom_claims.blank?
+    custom_claims.is_a?(Hash) ? custom_claims : {}
+  end
+
+  # Get fully merged claims for a specific application
+  def merged_claims_for_application(application)
+    merged = {}
+
+    # Start with group claims (in order)
+    groups.each do |group|
+      merged.merge!(group.parsed_custom_claims)
+    end
+
+    # Merge user global claims
+    merged.merge!(parsed_custom_claims)
+
+    # Merge app-specific claims (highest priority)
+    merged.merge!(application.custom_claims_for_user(self))
+
+    merged
   end
 
   private
 
+  def no_reserved_claim_names
+    return if custom_claims.blank?
+
+    reserved_used = parsed_custom_claims.keys.map(&:to_s) & RESERVED_CLAIMS
+    if reserved_used.any?
+      errors.add(:custom_claims, "cannot override reserved OIDC claims: #{reserved_used.join(', ')}")
+    end
+  end
+
   def generate_backup_codes
     # Generate plain codes for user to see/save
     plain_codes = Array.new(10) { SecureRandom.alphanumeric(8).upcase }

app/services/concerns/claims_merger.rb

@@ -0,0 +1,35 @@
+module ClaimsMerger
+  extend ActiveSupport::Concern
+
+  # Deep merge claims, combining arrays instead of overwriting them
+  # This ensures that array values (like roles) are combined across group/user/app claims
+  #
+  # Example:
+  #   base = { "roles" => ["user"], "level" => 1 }
+  #   incoming = { "roles" => ["admin"], "department" => "IT" }
+  #   deep_merge_claims(base, incoming)
+  #   # => { "roles" => ["user", "admin"], "level" => 1, "department" => "IT" }
+  def deep_merge_claims(base, incoming)
+    result = base.dup
+
+    incoming.each do |key, value|
+      if result.key?(key)
+        # If both values are arrays, combine them (union to avoid duplicates)
+        if result[key].is_a?(Array) && value.is_a?(Array)
+          result[key] = (result[key] + value).uniq
+        # If both values are hashes, recursively merge them
+        elsif result[key].is_a?(Hash) && value.is_a?(Hash)
+          result[key] = deep_merge_claims(result[key], value)
+        else
+          # Otherwise, incoming value wins (override)
+          result[key] = value
+        end
+      else
+        # New key, just add it
+        result[key] = value
+      end
+    end
+
+    result
+  end
+end

app/services/oidc_jwt_service.rb

@@ -1,4 +1,6 @@
 class OidcJwtService
+  extend ClaimsMerger
+
   class << self
     # Generate an ID token (JWT) for the user
     def generate_id_token(user, application, consent: nil, nonce: nil)
@@ -17,7 +19,7 @@ class OidcJwtService
         iat: now,
         email: user.email_address,
         email_verified: true,
-        preferred_username: user.email_address,
+        preferred_username: user.username.presence || user.email_address,
         name: user.name.presence || user.email_address
       }
 
@@ -29,17 +31,41 @@ class OidcJwtService
         payload[:groups] = user.groups.pluck(:name)
       end
 
-      # Add admin claim if user is admin
-      payload[:admin] = true if user.admin?
-
-      # Merge custom claims from groups
+      # Merge custom claims from groups (arrays are combined, not overwritten)
       user.groups.each do |group|
-        payload.merge!(group.parsed_custom_claims)
+        payload = deep_merge_claims(payload, group.parsed_custom_claims)
       end
 
-      # Merge custom claims from user (overrides group claims)
-      payload.merge!(user.parsed_custom_claims)
+      # Merge custom claims from user (arrays are combined, other values override)
+      payload = deep_merge_claims(payload, user.parsed_custom_claims)
 
+      # Merge app-specific custom claims (highest priority, arrays are combined)
+      payload = deep_merge_claims(payload, application.custom_claims_for_user(user))
+
+      JWT.encode(payload, private_key, "RS256", { kid: key_id, typ: "JWT" })
+    end
+
+    # Generate a backchannel logout token (JWT)
+    # Per OIDC Back-Channel Logout spec, this token:
+    # - MUST include iss, aud, iat, jti, events claims
+    # - MUST include sub or sid (or both) - we always include both
+    # - MUST NOT include nonce claim
+    def generate_logout_token(user, application, consent)
+      now = Time.current.to_i
+
+      payload = {
+        iss: issuer_url,
+        sub: consent.sid,  # Pairwise subject identifier
+        aud: application.client_id,
+        iat: now,
+        jti: SecureRandom.uuid,  # Unique identifier for this logout token
+        sid: consent.sid,  # Session ID - always included for granular logout
+        events: {
+          "http://schemas.openid.net/event/backchannel-logout" => {}
+        }
+      }
+
+      # Important: Do NOT include nonce in logout tokens (spec requirement)
       JWT.encode(payload, private_key, "RS256", { kid: key_id, typ: "JWT" })
     end
 

app/views/admin/applications/_form.html.erb

@@ -17,6 +17,87 @@
     <%= form.text_area :description, rows: 3, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm", placeholder: "Optional description of this application" %>
   </div>
 
+  <div>
+    <div class="flex items-center justify-between">
+      <%= form.label :icon, "Application Icon", class: "block text-sm font-medium text-gray-700" %>
+      <a href="https://dashboardicons.com" target="_blank" rel="noopener noreferrer" class="text-xs text-blue-600 hover:text-blue-800 flex items-center gap-1">
+        <svg class="w-3 h-3" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002 2h10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14"></path>
+        </svg>
+        Browse icons at dashboardicons.com
+      </a>
+    </div>
+    <% if application.icon.attached? && application.persisted? %>
+      <% begin %>
+        <%# Only show icon if we can successfully get its URL (blob is persisted) %>
+        <% if application.icon.blob&.persisted? && application.icon.blob.key.present? %>
+          <div class="mt-2 mb-3 flex items-center gap-4">
+            <%= image_tag application.icon, class: "h-16 w-16 rounded-lg object-cover border border-gray-200", alt: "Current icon" %>
+            <div class="text-sm text-gray-600">
+              <p class="font-medium">Current icon</p>
+              <p class="text-xs"><%= number_to_human_size(application.icon.blob.byte_size) %></p>
+            </div>
+          </div>
+        <% end %>
+      <% rescue ArgumentError => e %>
+        <%# Handle case where icon attachment exists but can't generate signed_id %>
+        <% if e.message.include?("Cannot get a signed_id for a new record") %>
+          <div class="mt-2 mb-3 text-sm text-gray-600">
+            <p class="font-medium">Icon uploaded</p>
+            <p class="text-xs">File will be processed shortly</p>
+          </div>
+        <% else %>
+          <%# Re-raise if it's a different error %>
+          <% raise e %>
+        <% end %>
+      <% end %>
+    <% end %>
+
+    <div class="mt-2" data-controller="file-drop image-paste">
+      <div class="flex justify-center px-6 pt-5 pb-6 border-2 border-gray-300 border-dashed rounded-md hover:border-blue-400 transition-colors"
+           data-file-drop-target="dropzone"
+           data-image-paste-target="dropzone"
+           data-action="dragover->file-drop#dragover dragleave->file-drop#dragleave drop->file-drop#drop paste->image-paste#handlePaste"
+           tabindex="0">
+        <div class="space-y-1 text-center">
+          <svg class="mx-auto h-12 w-12 text-gray-400" stroke="currentColor" fill="none" viewBox="0 0 48 48">
+            <path d="M28 8H12a4 4 0 00-4 4v20m32-12v8m0 0v8a4 4 0 01-4 4H12a4 4 0 01-4-4v-4m32-4l-3.172-3.172a4 4 0 00-5.656 0L28 28M8 32l9.172-9.172a4 4 0 015.656 0L28 28m0 0l4 4m4-24h8m-4-4v8m-12 4h.02" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" />
+          </svg>
+          <div class="flex text-sm text-gray-600">
+            <label for="<%= form.field_id(:icon) %>" class="relative cursor-pointer bg-white rounded-md font-medium text-blue-600 hover:text-blue-500 focus-within:outline-none focus-within:ring-2 focus-within:ring-offset-2 focus-within:ring-blue-500">
+              <span>Upload a file</span>
+              <%= form.file_field :icon,
+                  accept: "image/png,image/jpg,image/jpeg,image/gif,image/svg+xml",
+                  class: "sr-only",
+                  data: {
+                    file_drop_target: "input",
+                    image_paste_target: "input",
+                    action: "change->file-drop#handleFiles"
+                  } %>
+            </label>
+            <p class="pl-1">or drag and drop</p>
+          </div>
+          <p class="text-xs text-gray-500">PNG, JPG, GIF, or SVG up to 2MB</p>
+          <p class="text-xs text-blue-600 font-medium mt-2">💡 Tip: Click here and press Ctrl+V (or Cmd+V) to paste an image from your clipboard</p>
+        </div>
+      </div>
+      <div data-file-drop-target="preview" class="mt-3 hidden">
+        <div class="flex items-center gap-3 p-3 bg-blue-50 rounded-md border border-blue-200">
+          <img data-file-drop-target="previewImage" class="h-12 w-12 rounded object-cover" alt="Preview">
+          <div class="flex-1 min-w-0">
+            <p class="text-sm font-medium text-gray-900" data-file-drop-target="filename"></p>
+            <p class="text-xs text-gray-500" data-file-drop-target="filesize"></p>
+          </div>
+          <button type="button" data-action="click->file-drop#clear" class="text-gray-400 hover:text-gray-600">
+            <svg class="h-5 w-5" fill="currentColor" viewBox="0 0 20 20">
+              <path fill-rule="evenodd" d="M4.293 4.293a1 1 0 011.414 0L10 8.586l4.293-4.293a1 1 0 111.414 1.414L11.414 10l4.293 4.293a1 1 0 01-1.414 1.414L10 11.414l-4.293 4.293a1 1 0 01-1.414-1.414L8.586 10 4.293 5.707a1 1 0 010-1.414z" clip-rule="evenodd" />
+            </svg>
+          </button>
+        </div>
+      </div>
+    </div>
+  </div>
+
   <div>
     <%= form.label :landing_url, "Landing URL", class: "block text-sm font-medium text-gray-700" %>
     <%= form.url_field :landing_url, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm", placeholder: "https://app.example.com" %>
@@ -45,6 +126,16 @@
       <p class="mt-1 text-sm text-gray-500">One URI per line. These are the allowed callback URLs for your application.</p>
     </div>
 
+    <div>
+      <%= form.label :backchannel_logout_uri, "Backchannel Logout URI (Optional)", class: "block text-sm font-medium text-gray-700" %>
+      <%= form.url_field :backchannel_logout_uri, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm font-mono", placeholder: "https://app.example.com/oidc/backchannel-logout" %>
+      <p class="mt-1 text-sm text-gray-500">
+        If the application supports OpenID Connect Backchannel Logout, enter the logout endpoint URL.
+        When users log out, Clinch will send logout notifications to this endpoint for immediate session termination.
+        Leave blank if the application doesn't support backchannel logout.
+      </p>
+    </div>
+
     <div class="border-t border-gray-200 pt-4 mt-4">
       <h4 class="text-sm font-semibold text-gray-900 mb-3">Token Expiration Settings</h4>
       <p class="text-sm text-gray-500 mb-4">Configure how long tokens remain valid. Shorter times are more secure but require more frequent refreshes.</p>

app/views/admin/applications/index.html.erb

@@ -14,7 +14,7 @@
       <table class="min-w-full divide-y divide-gray-300">
         <thead>
           <tr>
-            <th scope="col" class="py-3.5 pl-4 pr-3 text-left text-sm font-semibold text-gray-900 sm:pl-0">Name</th>
+            <th scope="col" class="py-3.5 pl-4 pr-3 text-left text-sm font-semibold text-gray-900 sm:pl-0">Application</th>
             <th scope="col" class="px-3 py-3.5 text-left text-sm font-semibold text-gray-900">Slug</th>
             <th scope="col" class="px-3 py-3.5 text-left text-sm font-semibold text-gray-900">Type</th>
             <th scope="col" class="px-3 py-3.5 text-left text-sm font-semibold text-gray-900">Status</th>
@@ -28,7 +28,18 @@
           <% @applications.each do |application| %>
             <tr>
               <td class="whitespace-nowrap py-4 pl-4 pr-3 text-sm font-medium text-gray-900 sm:pl-0">
+                <div class="flex items-center gap-3">
+                  <% if application.icon.attached? %>
+                    <%= image_tag application.icon, class: "h-10 w-10 rounded-lg object-cover border border-gray-200 flex-shrink-0", alt: "#{application.name} icon" %>
+                  <% else %>
+                    <div class="h-10 w-10 rounded-lg bg-gray-100 border border-gray-200 flex items-center justify-center flex-shrink-0">
+                      <svg class="h-6 w-6 text-gray-400" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+                      </svg>
+                    </div>
+                  <% end %>
                   <%= link_to application.name, admin_application_path(application), class: "text-blue-600 hover:text-blue-900" %>
+                </div>
               </td>
               <td class="whitespace-nowrap px-3 py-4 text-sm text-gray-500">
                 <code class="text-xs bg-gray-100 px-2 py-1 rounded"><%= application.slug %></code>

app/views/admin/applications/show.html.erb

@@ -16,11 +16,22 @@
     </div>
   <% end %>
 
-  <div class="sm:flex sm:items-center sm:justify-between">
+  <div class="sm:flex sm:items-start sm:justify-between">
+    <div class="flex items-start gap-4">
+      <% if @application.icon.attached? %>
+        <%= image_tag @application.icon, class: "h-16 w-16 rounded-lg object-cover border border-gray-200 shrink-0", alt: "#{@application.name} icon" %>
+      <% else %>
+        <div class="h-16 w-16 rounded-lg bg-gray-100 border border-gray-200 flex items-center justify-center shrink-0">
+          <svg class="h-8 w-8 text-gray-400" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+          </svg>
+        </div>
+      <% end %>
       <div>
         <h1 class="text-2xl font-semibold text-gray-900"><%= @application.name %></h1>
         <p class="mt-1 text-sm text-gray-500"><%= @application.description %></p>
       </div>
+    </div>
     <div class="mt-4 sm:mt-0 flex gap-3">
       <%= link_to "Edit", edit_admin_application_path(@application), class: "rounded-md bg-white px-3 py-2 text-sm font-semibold text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50" %>
       <%= button_to "Delete", admin_application_path(@application), method: :delete, data: { turbo_confirm: "Are you sure?" }, class: "rounded-md bg-red-600 px-3 py-2 text-sm font-semibold text-white shadow-sm hover:bg-red-500" %>
@@ -78,10 +89,11 @@
     <div class="bg-white shadow sm:rounded-lg">
       <div class="px-4 py-5 sm:p-6">
         <div class="flex items-center justify-between mb-4">
-          <h3 class="text-base font-semibold leading-6 text-gray-900">OIDC Credentials</h3>
+          <h3 class="text-base font-semibold leading-6 text-gray-900">OIDC Configuration</h3>
           <%= button_to "Regenerate Credentials", regenerate_credentials_admin_application_path(@application), method: :post, data: { turbo_confirm: "This will invalidate the current credentials. Continue?" }, class: "text-sm text-red-600 hover:text-red-900" %>
         </div>
         <dl class="space-y-4">
+          <% unless flash[:client_id] && flash[:client_secret] %>
             <div>
               <dt class="text-sm font-medium text-gray-500">Client ID</dt>
               <dd class="mt-1 text-sm text-gray-900">
@@ -99,6 +111,7 @@
                 </p>
               </dd>
             </div>
+          <% end %>
           <div>
             <dt class="text-sm font-medium text-gray-500">Redirect URIs</dt>
             <dd class="mt-1 text-sm text-gray-900">
@@ -111,6 +124,27 @@
               <% end %>
             </dd>
           </div>
+          <div>
+            <dt class="text-sm font-medium text-gray-500">
+              Backchannel Logout URI
+              <% if @application.supports_backchannel_logout? %>
+                <span class="ml-2 inline-flex items-center rounded-full bg-green-100 px-2 py-0.5 text-xs font-medium text-green-700">Enabled</span>
+              <% end %>
+            </dt>
+            <dd class="mt-1 text-sm text-gray-900">
+              <% if @application.backchannel_logout_uri.present? %>
+                <code class="block bg-gray-100 px-3 py-2 rounded font-mono text-xs break-all"><%= @application.backchannel_logout_uri %></code>
+                <p class="mt-2 text-xs text-gray-500">
+                  When users log out, Clinch will send logout notifications to this endpoint for immediate session termination.
+                </p>
+              <% else %>
+                <span class="text-gray-400 italic">Not configured</span>
+                <p class="mt-1 text-xs text-gray-500">
+                  Backchannel logout is optional. Configure it if the application supports OpenID Connect Backchannel Logout.
+                </p>
+              <% end %>
+            </dd>
+          </div>
         </dl>
       </div>
     </div>

app/views/admin/users/_application_claims.html.erb

@@ -0,0 +1,185 @@
+<% oidc_apps = applications.select(&:oidc?) %>
+<% forward_auth_apps = applications.select(&:forward_auth?) %>
+
+<!-- OIDC Apps: Custom Claims -->
+<% if oidc_apps.any? %>
+  <div class="mt-12 border-t pt-8">
+    <h2 class="text-xl font-semibold text-gray-900 mb-4">OIDC App-Specific Claims</h2>
+    <p class="text-sm text-gray-600 mb-6">
+      Configure custom claims that apply only to specific OIDC applications. These override both group and user global claims and are included in ID tokens.
+    </p>
+
+    <div class="space-y-6">
+      <% oidc_apps.each do |app| %>
+        <% app_claim = user.application_user_claims.find_by(application: app) %>
+        <details class="border rounded-lg" <%= "open" if app_claim&.custom_claims&.any? %>>
+          <summary class="cursor-pointer bg-gray-50 px-4 py-3 hover:bg-gray-100 rounded-t-lg flex items-center justify-between">
+            <div class="flex items-center gap-3">
+              <span class="font-medium text-gray-900"><%= app.name %></span>
+              <span class="text-xs px-2 py-1 rounded-full bg-blue-100 text-blue-700">
+                OIDC
+              </span>
+              <% if app_claim&.custom_claims&.any? %>
+                <span class="text-xs px-2 py-1 rounded-full bg-amber-100 text-amber-700">
+                  <%= app_claim.custom_claims.keys.count %> claim(s)
+                </span>
+              <% end %>
+            </div>
+            <svg class="h-5 w-5 text-gray-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7" />
+            </svg>
+          </summary>
+
+          <div class="p-4 space-y-4">
+            <%= form_with url: update_application_claims_admin_user_path(user), method: :post, class: "space-y-4", data: { controller: "json-validator" } do |form| %>
+              <%= hidden_field_tag :application_id, app.id %>
+
+              <div>
+                <label class="block text-sm font-medium text-gray-700 mb-2">Custom Claims (JSON)</label>
+                <%= text_area_tag :custom_claims,
+                    (app_claim&.custom_claims.present? ? JSON.pretty_generate(app_claim.custom_claims) : ""),
+                    rows: 8,
+                    class: "w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm font-mono",
+                    placeholder: '{"kavita_groups": ["admin"], "library_access": "all"}',
+                    data: {
+                      action: "input->json-validator#validate blur->json-validator#format",
+                      json_validator_target: "textarea"
+                    } %>
+                <div class="mt-2 space-y-1">
+                  <p class="text-xs text-gray-600">
+                    Example for <%= app.name %>: Add claims that this app specifically needs to read.
+                  </p>
+                  <p class="text-xs text-amber-600">
+                    <strong>Note:</strong> Do not use reserved claim names (<code class="bg-amber-50 px-1 rounded">groups</code>, <code class="bg-amber-50 px-1 rounded">email</code>, <code class="bg-amber-50 px-1 rounded">name</code>, etc.). Use app-specific names like <code class="bg-amber-50 px-1 rounded">kavita_groups</code> instead.
+                  </p>
+                  <div data-json-validator-target="status" class="text-xs font-medium"></div>
+                </div>
+              </div>
+
+              <div class="flex gap-3">
+                <%= button_tag type: :submit, class: "rounded-md bg-blue-600 px-3 py-2 text-sm font-semibold text-white shadow-sm hover:bg-blue-500" do %>
+                  <%= app_claim ? "Update" : "Add" %> Claims
+                <% end %>
+
+                <% if app_claim %>
+                  <%= button_to "Remove Override",
+                      delete_application_claims_admin_user_path(user, application_id: app.id),
+                      method: :delete,
+                      data: { turbo_confirm: "Remove app-specific claims for #{app.name}?" },
+                      class: "rounded-md bg-white px-3 py-2 text-sm font-semibold text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50" %>
+                <% end %>
+              </div>
+            <% end %>
+
+            <!-- Preview merged claims -->
+            <div class="mt-4 border-t pt-4">
+              <h4 class="text-sm font-medium text-gray-700 mb-2">Preview: Final ID Token Claims for <%= app.name %></h4>
+              <div class="bg-gray-50 rounded-lg p-3">
+                <pre class="text-xs font-mono text-gray-800 overflow-x-auto"><%= JSON.pretty_generate(preview_user_claims(user, app)) %></pre>
+              </div>
+
+              <details class="mt-2">
+                <summary class="cursor-pointer text-xs text-gray-600 hover:text-gray-900">Show claim sources</summary>
+                <div class="mt-2 space-y-1">
+                  <% claim_sources(user, app).each do |source| %>
+                    <div class="flex gap-2 items-start text-xs">
+                      <span class="px-2 py-1 rounded <%= source[:type] == :group ? 'bg-blue-100 text-blue-700' : (source[:type] == :user ? 'bg-green-100 text-green-700' : 'bg-amber-100 text-amber-700') %>">
+                        <%= source[:name] %>
+                      </span>
+                      <code class="text-gray-700"><%= source[:claims].to_json %></code>
+                    </div>
+                  <% end %>
+                </div>
+              </details>
+            </div>
+          </div>
+        </details>
+      <% end %>
+    </div>
+  </div>
+<% end %>
+
+<!-- ForwardAuth Apps: Headers Preview -->
+<% if forward_auth_apps.any? %>
+  <div class="mt-12 border-t pt-8">
+    <h2 class="text-xl font-semibold text-gray-900 mb-4">ForwardAuth Headers Preview</h2>
+    <p class="text-sm text-gray-600 mb-6">
+      ForwardAuth applications receive HTTP headers (not OIDC tokens). Headers are based on user's email, name, groups, and admin status.
+    </p>
+
+    <div class="space-y-6">
+      <% forward_auth_apps.each do |app| %>
+        <details class="border rounded-lg">
+          <summary class="cursor-pointer bg-gray-50 px-4 py-3 hover:bg-gray-100 rounded-t-lg flex items-center justify-between">
+            <div class="flex items-center gap-3">
+              <span class="font-medium text-gray-900"><%= app.name %></span>
+              <span class="text-xs px-2 py-1 rounded-full bg-green-100 text-green-700">
+                FORWARD AUTH
+              </span>
+              <span class="text-xs text-gray-500">
+                <%= app.domain_pattern %>
+              </span>
+            </div>
+            <svg class="h-5 w-5 text-gray-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7" />
+            </svg>
+          </summary>
+
+          <div class="p-4 space-y-4">
+            <div class="bg-blue-50 border border-blue-200 rounded-lg p-3">
+              <div class="flex items-start">
+                <svg class="h-5 w-5 text-blue-400 mr-2 flex-shrink-0 mt-0.5" fill="currentColor" viewBox="0 0 20 20">
+                  <path fill-rule="evenodd" d="M18 10a8 8 0 11-16 0 8 8 0 0116 0zm-7-4a1 1 0 11-2 0 1 1 0 012 0zM9 9a1 1 0 000 2v3a1 1 0 001 1h1a1 1 0 100-2v-3a1 1 0 00-1-1H9z" clip-rule="evenodd" />
+                </svg>
+              </div>
+            </div>
+
+            <div>
+              <h4 class="text-sm font-medium text-gray-700 mb-2">Headers Sent to <%= app.name %></h4>
+              <div class="bg-gray-50 rounded-lg p-3 border">
+                <% headers = app.headers_for_user(user) %>
+                <% if headers.any? %>
+                  <dl class="space-y-2 text-xs font-mono">
+                    <% headers.each do |header_name, value| %>
+                      <div class="flex">
+                        <dt class="text-blue-600 font-semibold w-48"><%= header_name %>:</dt>
+                        <dd class="text-gray-800 flex-1"><%= value %></dd>
+                      </div>
+                    <% end %>
+                  </dl>
+                <% else %>
+                  <p class="text-xs text-gray-500 italic">All headers disabled for this application.</p>
+                <% end %>
+              </div>
+              <p class="mt-2 text-xs text-gray-500">
+                These headers are configured in the application settings and sent by your reverse proxy (Caddy/Traefik) to the upstream application.
+              </p>
+            </div>
+
+            <% if user.groups.any? %>
+              <div>
+                <h4 class="text-sm font-medium text-gray-700 mb-2">User's Groups</h4>
+                <div class="flex flex-wrap gap-2">
+                  <% user.groups.each do |group| %>
+                    <span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-blue-100 text-blue-800">
+                      <%= group.name %>
+                    </span>
+                  <% end %>
+                </div>
+              </div>
+            <% end %>
+          </div>
+        </details>
+      <% end %>
+    </div>
+  </div>
+<% end %>
+
+<% if oidc_apps.empty? && forward_auth_apps.empty? %>
+  <div class="mt-12 border-t pt-8">
+    <div class="text-center py-12 bg-gray-50 rounded-lg">
+      <p class="text-gray-500">No active applications found.</p>
+      <p class="text-sm text-gray-400 mt-1">Create applications in the Admin panel first.</p>
+    </div>
+  </div>
+<% end %>

app/views/admin/users/_form.html.erb

@@ -6,10 +6,16 @@
     <%= form.email_field :email_address, required: true, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm", placeholder: "user@example.com" %>
   </div>
 
+  <div>
+    <%= form.label :username, "Username (Optional)", class: "block text-sm font-medium text-gray-700" %>
+    <%= form.text_field :username, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm", placeholder: "jsmith" %>
+    <p class="mt-1 text-sm text-gray-500">Optional: Short username/handle for login. Can only contain letters, numbers, underscores, and hyphens.</p>
+  </div>
+
   <div>
     <%= form.label :name, "Display Name (Optional)", class: "block text-sm font-medium text-gray-700" %>
     <%= form.text_field :name, class: "mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm", placeholder: "John Smith" %>
-    <p class="mt-1 text-sm text-gray-500">Optional: Name shown in applications. Defaults to email address if not set.</p>
+    <p class="mt-1 text-sm text-gray-500">Optional: Full name shown in applications. Defaults to email address if not set.</p>
   </div>
 
   <div>

app/views/admin/users/edit.html.erb

@@ -1,5 +1,12 @@
-<div class="max-w-2xl">
+<div class="max-w-4xl">
   <h1 class="text-2xl font-semibold text-gray-900 mb-6">Edit User</h1>
   <p class="text-sm text-gray-600 mb-6">Editing: <%= @user.email_address %></p>
+
+  <div class="max-w-2xl">
     <%= render "form", user: @user %>
+  </div>
+
+  <% if @user.persisted? %>
+    <%= render "application_claims", user: @user, applications: @applications %>
+  <% end %>
 </div>

app/views/dashboard/index.html.erb

@@ -102,11 +102,22 @@
       <% @applications.each do |app| %>
         <div class="bg-white rounded-lg border border-gray-200 shadow-sm hover:shadow-md transition">
           <div class="p-6">
-            <div class="flex items-center justify-between mb-3">
+            <div class="flex items-start gap-3 mb-4">
+              <% if app.icon.attached? %>
+                <%= image_tag app.icon, class: "h-12 w-12 rounded-lg object-cover border border-gray-200 shrink-0", alt: "#{app.name} icon" %>
+              <% else %>
+                <div class="h-12 w-12 rounded-lg bg-gray-100 border border-gray-200 flex items-center justify-center shrink-0">
+                  <svg class="h-6 w-6 text-gray-400" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+                    <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+                  </svg>
+                </div>
+              <% end %>
+              <div class="flex-1 min-w-0">
+                <div class="flex items-start justify-between">
                   <h3 class="text-lg font-semibold text-gray-900 truncate">
                     <%= app.name %>
                   </h3>
-              <span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium
+                  <span class="ml-2 inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium shrink-0
                     <% if app.oidc? %>
                       bg-blue-100 text-blue-800
                     <% else %>
@@ -115,15 +126,15 @@
                     <%= app.app_type.humanize %>
                   </span>
                 </div>
-
-            <p class="text-sm text-gray-600 mb-4">
-              <% if app.oidc? %>
-                OIDC Application
-              <% else %>
-                ForwardAuth Protected Application
-              <% end %>
+                <% if app.description.present? %>
+                  <p class="text-sm text-gray-600 mt-1 line-clamp-2">
+                    <%= app.description %>
                   </p>
+                <% end %>
+              </div>
+            </div>
 
+            <div class="space-y-2">
               <% if app.landing_url.present? %>
                 <%= link_to "Open Application", app.landing_url,
                     target: "_blank",
@@ -134,6 +145,13 @@
                   No landing URL configured
                 </div>
               <% end %>
+
+              <% if app.user_has_active_session?(@user) %>
+                <%= button_to "Logout", logout_from_app_active_sessions_path(application_id: app.id), method: :delete,
+                    class: "w-full flex justify-center items-center px-4 py-2 border border-orange-300 text-sm font-medium rounded-md text-orange-700 bg-white hover:bg-orange-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-orange-500 transition",
+                    form: { data: { turbo_confirm: "This will log you out of #{app.name}. You can sign back in without re-authorizing. Continue?" } } %>
+              <% end %>
+            </div>
           </div>
         </div>
       <% end %>

app/views/oidc/consent.html.erb

@@ -1,6 +1,15 @@
 <div class="mx-auto max-w-md">
   <div class="bg-white py-8 px-6 shadow rounded-lg sm:px-10">
-    <div class="mb-8">
+    <div class="mb-8 text-center">
+      <% if @application.icon.attached? %>
+        <%= image_tag @application.icon, class: "mx-auto h-20 w-20 rounded-xl object-cover border-2 border-gray-200 shadow-sm mb-4", alt: "#{@application.name} icon" %>
+      <% else %>
+        <div class="mx-auto h-20 w-20 rounded-xl bg-gray-100 border-2 border-gray-200 flex items-center justify-center mb-4">
+          <svg class="h-10 w-10 text-gray-400" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+          </svg>
+        </div>
+      <% end %>
       <h2 class="text-2xl font-bold text-gray-900">Authorize Application</h2>
       <p class="mt-2 text-sm text-gray-600">
         <strong><%= @application.name %></strong> is requesting access to your account.

config/initializers/active_storage.rb

@@ -0,0 +1,14 @@
+# Configure ActiveStorage content type resolution
+Rails.application.config.after_initialize do
+  # Ensure SVG files are served with the correct content type
+  ActiveStorage::Blob.class_eval do
+    def content_type_for_serving
+      # Override content type for SVG files
+      if filename.extension == "svg" && content_type == "application/octet-stream"
+        "image/svg+xml"
+      else
+        content_type
+      end
+    end
+  end
+end

config/initializers/version.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+module Clinch
+  VERSION = "0.6.3"
+end

config/recurring.yml

@@ -0,0 +1,17 @@
+# Solid Queue Recurring Jobs Configuration
+# This file defines scheduled/cron-like jobs that run periodically
+
+production:
+  oidc_token_cleanup:
+    class: OidcTokenCleanupJob
+    schedule: "0 3 * * *"  # Run daily at 3:00 AM
+    queue: default
+
+development:
+  oidc_token_cleanup:
+    class: OidcTokenCleanupJob
+    schedule: "0 3 * * *"  # Run daily at 3:00 AM
+    queue: default
+
+test:
+  # No recurring jobs in test environment

config/routes.rb

@@ -49,6 +49,7 @@ Rails.application.routes.draw do
   end
   resource :active_sessions, only: [:show] do
     member do
+      delete :logout_from_app
       delete :revoke_consent
       delete :revoke_all_consents
     end
@@ -82,6 +83,8 @@ Rails.application.routes.draw do
     resources :users do
       member do
         post :resend_invitation
+        post :update_application_claims
+        delete :delete_application_claims
       end
     end
     resources :applications do

config/storage.yml

@@ -4,7 +4,7 @@ test:
 
 local:
   service: Disk
-  root: <%= Rails.root.join("storage") %>
+  root: <%= Rails.root.join("storage/uploads") %>
 
 # Use bin/rails credentials:edit to set the AWS secrets (as aws:access_key_id|secret_access_key)
 # amazon:

db/migrate/20251122235519_add_sid_to_oidc_user_consent.rb

@@ -0,0 +1,15 @@
+class AddSidToOidcUserConsent < ActiveRecord::Migration[8.1]
+  def change
+    add_column :oidc_user_consents, :sid, :string
+    add_index :oidc_user_consents, :sid
+
+    # Generate UUIDs for existing consent records
+    reversible do |dir|
+      dir.up do
+        OidcUserConsent.where(sid: nil).find_each do |consent|
+          consent.update_column(:sid, SecureRandom.uuid)
+        end
+      end
+    end
+  end
+end

db/migrate/20251123052026_create_application_user_claims.rb

@@ -0,0 +1,13 @@
+class CreateApplicationUserClaims < ActiveRecord::Migration[8.1]
+  def change
+    create_table :application_user_claims do |t|
+      t.references :application, null: false, foreign_key: { on_delete: :cascade }
+      t.references :user, null: false, foreign_key: { on_delete: :cascade }
+      t.json :custom_claims, default: {}, null: false
+
+      t.timestamps
+    end
+
+    add_index :application_user_claims, [:application_id, :user_id], unique: true, name: 'index_app_user_claims_unique'
+  end
+end

db/migrate/20251125012446_add_username_to_users.rb

@@ -0,0 +1,6 @@
+class AddUsernameToUsers < ActiveRecord::Migration[8.1]
+  def change
+    add_column :users, :username, :string
+    add_index :users, :username, unique: true
+  end
+end

db/migrate/20251125063248_create_active_storage_tables.active_storage.rb

@@ -0,0 +1,57 @@
+# This migration comes from active_storage (originally 20170806125915)
+class CreateActiveStorageTables < ActiveRecord::Migration[7.0]
+  def change
+    # Use Active Record's configured type for primary and foreign keys
+    primary_key_type, foreign_key_type = primary_and_foreign_key_types
+
+    create_table :active_storage_blobs, id: primary_key_type do |t|
+      t.string   :key,          null: false
+      t.string   :filename,     null: false
+      t.string   :content_type
+      t.text     :metadata
+      t.string   :service_name, null: false
+      t.bigint   :byte_size,    null: false
+      t.string   :checksum
+
+      if connection.supports_datetime_with_precision?
+        t.datetime :created_at, precision: 6, null: false
+      else
+        t.datetime :created_at, null: false
+      end
+
+      t.index [ :key ], unique: true
+    end
+
+    create_table :active_storage_attachments, id: primary_key_type do |t|
+      t.string     :name,     null: false
+      t.references :record,   null: false, polymorphic: true, index: false, type: foreign_key_type
+      t.references :blob,     null: false, type: foreign_key_type
+
+      if connection.supports_datetime_with_precision?
+        t.datetime :created_at, precision: 6, null: false
+      else
+        t.datetime :created_at, null: false
+      end
+
+      t.index [ :record_type, :record_id, :name, :blob_id ], name: :index_active_storage_attachments_uniqueness, unique: true
+      t.foreign_key :active_storage_blobs, column: :blob_id
+    end
+
+    create_table :active_storage_variant_records, id: primary_key_type do |t|
+      t.belongs_to :blob, null: false, index: false, type: foreign_key_type
+      t.string :variation_digest, null: false
+
+      t.index [ :blob_id, :variation_digest ], name: :index_active_storage_variant_records_uniqueness, unique: true
+      t.foreign_key :active_storage_blobs, column: :blob_id
+    end
+  end
+
+  private
+    def primary_and_foreign_key_types
+      config = Rails.configuration.generators
+      setting = config.options[config.orm][:primary_key_type]
+      primary_key_type = setting || :primary_key
+      foreign_key_type = setting || :bigint
+      [ primary_key_type, foreign_key_type ]
+    end
+end

db/migrate/20251125081147_add_backchannel_logout_uri_to_applications.rb

@@ -0,0 +1,5 @@
+class AddBackchannelLogoutUriToApplications < ActiveRecord::Migration[8.1]
+  def change
+    add_column :applications, :backchannel_logout_uri, :string
+  end
+end

db/schema.rb

@@ -10,7 +10,35 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.1].define(version: 2025_11_22_235519) do
+ActiveRecord::Schema[8.1].define(version: 2025_11_25_081147) do
+  create_table "active_storage_attachments", force: :cascade do |t|
+    t.bigint "blob_id", null: false
+    t.datetime "created_at", null: false
+    t.string "name", null: false
+    t.bigint "record_id", null: false
+    t.string "record_type", null: false
+    t.index ["blob_id"], name: "index_active_storage_attachments_on_blob_id"
+    t.index ["record_type", "record_id", "name", "blob_id"], name: "index_active_storage_attachments_uniqueness", unique: true
+  end
+
+  create_table "active_storage_blobs", force: :cascade do |t|
+    t.bigint "byte_size", null: false
+    t.string "checksum"
+    t.string "content_type"
+    t.datetime "created_at", null: false
+    t.string "filename", null: false
+    t.string "key", null: false
+    t.text "metadata"
+    t.string "service_name", null: false
+    t.index ["key"], name: "index_active_storage_blobs_on_key", unique: true
+  end
+
+  create_table "active_storage_variant_records", force: :cascade do |t|
+    t.bigint "blob_id", null: false
+    t.string "variation_digest", null: false
+    t.index ["blob_id", "variation_digest"], name: "index_active_storage_variant_records_uniqueness", unique: true
+  end
+
   create_table "application_groups", force: :cascade do |t|
     t.integer "application_id", null: false
     t.datetime "created_at", null: false
@@ -21,10 +49,22 @@ ActiveRecord::Schema[8.1].define(version: 2025_11_22_235519) do
     t.index ["group_id"], name: "index_application_groups_on_group_id"
   end
 
+  create_table "application_user_claims", force: :cascade do |t|
+    t.integer "application_id", null: false
+    t.datetime "created_at", null: false
+    t.json "custom_claims", default: {}, null: false
+    t.datetime "updated_at", null: false
+    t.integer "user_id", null: false
+    t.index ["application_id", "user_id"], name: "index_app_user_claims_unique", unique: true
+    t.index ["application_id"], name: "index_application_user_claims_on_application_id"
+    t.index ["user_id"], name: "index_application_user_claims_on_user_id"
+  end
+
   create_table "applications", force: :cascade do |t|
     t.integer "access_token_ttl", default: 3600
     t.boolean "active", default: true, null: false
     t.string "app_type", null: false
+    t.string "backchannel_logout_uri"
     t.string "client_id"
     t.string "client_secret_digest"
     t.datetime "created_at", null: false
@@ -169,10 +209,12 @@ ActiveRecord::Schema[8.1].define(version: 2025_11_22_235519) do
     t.boolean "totp_required", default: false, null: false
     t.string "totp_secret"
     t.datetime "updated_at", null: false
+    t.string "username"
     t.string "webauthn_id"
     t.boolean "webauthn_required", default: false, null: false
     t.index ["email_address"], name: "index_users_on_email_address", unique: true
     t.index ["status"], name: "index_users_on_status"
+    t.index ["username"], name: "index_users_on_username", unique: true
     t.index ["webauthn_id"], name: "index_users_on_webauthn_id", unique: true
   end
 
@@ -198,8 +240,12 @@ ActiveRecord::Schema[8.1].define(version: 2025_11_22_235519) do
     t.index ["user_id"], name: "index_webauthn_credentials_on_user_id"
   end
 
+  add_foreign_key "active_storage_attachments", "active_storage_blobs", column: "blob_id"
+  add_foreign_key "active_storage_variant_records", "active_storage_blobs", column: "blob_id"
   add_foreign_key "application_groups", "applications"
   add_foreign_key "application_groups", "groups"
+  add_foreign_key "application_user_claims", "applications", on_delete: :cascade
+  add_foreign_key "application_user_claims", "users", on_delete: :cascade
   add_foreign_key "oidc_access_tokens", "applications"
   add_foreign_key "oidc_access_tokens", "users"
   add_foreign_key "oidc_authorization_codes", "applications"

test/controllers/oidc_authorization_code_security_test.rb

@@ -19,8 +19,9 @@ class OidcAuthorizationCodeSecurityTest < ActionDispatch::IntegrationTest
   end
 
   def teardown
-    OidcAuthorizationCode.where(application: @application).destroy_all
-    OidcAccessToken.where(application: @application).destroy_all
+    OidcAuthorizationCode.where(application: @application).delete_all
+    # Use delete_all to avoid triggering callbacks that might have issues with the schema
+    OidcAccessToken.where(application: @application).delete_all
     @user.destroy
     @application.destroy
   end

test/controllers/passwords_controller_test.rb

@@ -11,7 +11,7 @@ class PasswordsControllerTest < ActionDispatch::IntegrationTest
   test "create" do
     post passwords_path, params: { email_address: @user.email_address }
     assert_enqueued_email_with PasswordsMailer, :reset, args: [ @user ]
-    assert_redirected_to new_session_path
+    assert_redirected_to signin_path
 
     follow_redirect!
     assert_notice "reset instructions sent"
@@ -20,14 +20,14 @@ class PasswordsControllerTest < ActionDispatch::IntegrationTest
   test "create for an unknown user redirects but sends no mail" do
     post passwords_path, params: { email_address: "missing-user@example.com" }
     assert_enqueued_emails 0
-    assert_redirected_to new_session_path
+    assert_redirected_to signin_path
 
     follow_redirect!
     assert_notice "reset instructions sent"
   end
 
   test "edit" do
-    get edit_password_path(@user.password_reset_token)
+    get edit_password_path(@user.generate_token_for(:password_reset))
     assert_response :success
   end
 
@@ -41,8 +41,8 @@ class PasswordsControllerTest < ActionDispatch::IntegrationTest
 
   test "update" do
     assert_changes -> { @user.reload.password_digest } do
-      put password_path(@user.password_reset_token), params: { password: "new", password_confirmation: "new" }
-      assert_redirected_to new_session_path
+      put password_path(@user.generate_token_for(:password_reset)), params: { password: "newpassword", password_confirmation: "newpassword" }
+      assert_redirected_to signin_path
     end
 
     follow_redirect!

test/controllers/sessions_controller_test.rb

@@ -18,7 +18,7 @@ class SessionsControllerTest < ActionDispatch::IntegrationTest
   test "create with invalid credentials" do
     post session_path, params: { email_address: @user.email_address, password: "wrong" }
 
-    assert_redirected_to new_session_path
+    assert_redirected_to signin_path
     assert_nil cookies[:session_id]
   end
 
@@ -27,7 +27,7 @@ class SessionsControllerTest < ActionDispatch::IntegrationTest
 
     delete session_path
 
-    assert_redirected_to new_session_path
+    assert_redirected_to signin_path
     assert_empty cookies[:session_id]
   end
 end

test/fixtures/application_user_claims.yml

@@ -0,0 +1,11 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+kavita_alice_claims:
+  application: kavita_app
+  user: alice
+  custom_claims: { "kavita_groups": ["admin"], "library_access": "all" }
+
+abs_alice_claims:
+  application: audiobookshelf_app
+  user: alice
+  custom_claims: { "abs_groups": ["user"], "abs_permissions": { "canDownload": true, "canUpload": false } }

test/fixtures/applications.yml

@@ -24,3 +24,14 @@ another_app:
     https://app.example.com/auth/callback
   metadata: "{}"
   active: true
+
+audiobookshelf_app:
+  name: Audiobookshelf
+  slug: audiobookshelf
+  app_type: oidc
+  client_id: <%= SecureRandom.urlsafe_base64(32) %>
+  client_secret_digest: <%= BCrypt::Password.create(SecureRandom.urlsafe_base64(48)) %>
+  redirect_uris: |
+    https://abs.example.com/auth/openid/callback
+  metadata: "{}"
+  active: true

test/fixtures/groups.yml

@@ -1,5 +1,13 @@
 # Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
 
+one:
+  name: Group One
+  description: First test group
+
+two:
+  name: Group Two
+  description: Second test group
+
 admin_group:
   name: Administrators
   description: System administrators with full access

test/fixtures/users.yml

@@ -1,5 +1,17 @@
 <% password_digest = BCrypt::Password.create("password") %>
 
+one:
+  email_address: one@example.com
+  password_digest: <%= password_digest %>
+  admin: false
+  status: 0 # active
+
+two:
+  email_address: two@example.com
+  password_digest: <%= password_digest %>
+  admin: true
+  status: 0 # active
+
 alice:
   email_address: alice@example.com
   password_digest: <%= password_digest %>

test/integration/forward_auth_integration_test.rb

@@ -58,8 +58,8 @@ class ForwardAuthIntegrationTest < ActionDispatch::IntegrationTest
   # Domain and Rule Integration Tests
   test "different domain patterns with same session" do
     # Create test rules
-    wildcard_rule = ForwardAuthRule.create!(domain_pattern: "*.example.com", active: true)
-    exact_rule = ForwardAuthRule.create!(domain_pattern: "api.example.com", active: true)
+    wildcard_rule = Application.create!(domain_pattern: "*.example.com", active: true)
+    exact_rule = Application.create!(domain_pattern: "api.example.com", active: true)
 
     # Sign in
     post "/signin", params: { email_address: @user.email_address, password: "password" }
@@ -82,7 +82,7 @@ class ForwardAuthIntegrationTest < ActionDispatch::IntegrationTest
 
   test "group-based access control integration" do
     # Create restricted rule
-    restricted_rule = ForwardAuthRule.create!(domain_pattern: "restricted.example.com", active: true)
+    restricted_rule = Application.create!(domain_pattern: "restricted.example.com", active: true)
     restricted_rule.allowed_groups << @group
 
     # Sign in user without group
@@ -104,17 +104,19 @@ class ForwardAuthIntegrationTest < ActionDispatch::IntegrationTest
 
   # Header Configuration Integration Tests
   test "different header configurations with same user" do
-    # Create rules with different header configs
-    default_rule = ForwardAuthRule.create!(domain_pattern: "default.example.com", active: true)
-    custom_rule = ForwardAuthRule.create!(
+    # Create applications with different configs
+    default_rule = Application.create!(name: "Default App", slug: "default-app", app_type: "forward_auth", domain_pattern: "default.example.com", active: true)
+    custom_rule = Application.create!(
+      name: "Custom App", slug: "custom-app", app_type: "forward_auth",
       domain_pattern: "custom.example.com",
       active: true,
-      headers_config: { user: "X-WEBAUTH-USER", groups: "X-WEBAUTH-ROLES" }
+      metadata: { headers: { user: "X-WEBAUTH-USER", groups: "X-WEBAUTH-ROLES" } }.to_json
     )
-    no_headers_rule = ForwardAuthRule.create!(
+    no_headers_rule = Application.create!(
+      name: "No Headers App", slug: "no-headers-app", app_type: "forward_auth",
       domain_pattern: "noheaders.example.com",
       active: true,
-      headers_config: { user: "", email: "", name: "", groups: "", admin: "" }
+      metadata: { headers: { user: "", email: "", name: "", groups: "", admin: "" } }.to_json
     )
 
     # Add user to groups
@@ -191,7 +193,7 @@ class ForwardAuthIntegrationTest < ActionDispatch::IntegrationTest
     admin_user = users(:two)
 
     # Create restricted rule
-    admin_rule = ForwardAuthRule.create!(
+    admin_rule = Application.create!(
       domain_pattern: "admin.example.com",
       active: true,
       headers_config: { user: "X-Admin-User", admin: "X-Admin-Flag" }

test/jobs/invitations_mailer_test.rb

@@ -25,8 +25,8 @@ class InvitationsMailerTest < ActionMailer::TestCase
 
     assert_equal "You're invited to join Clinch", email.subject
     assert_equal [@user.email_address], email.to
-    assert_equal [], email.cc
-    assert_equal [], email.bcc
+    assert_equal [], email.cc || []
+    assert_equal [], email.bcc || []
     # From address is configured in ApplicationMailer
     assert_not_nil email.from
     assert email.from.is_a?(Array)

test/jobs/passwords_mailer_test.rb

@@ -25,8 +25,8 @@ class PasswordsMailerTest < ActionMailer::TestCase
 
     assert_equal "Reset your password", email.subject
     assert_equal [@user.email_address], email.to
-    assert_equal [], email.cc
-    assert_equal [], email.bcc
+    assert_equal [], email.cc || []
+    assert_equal [], email.bcc || []
     # From address is configured in ApplicationMailer
     assert_not_nil email.from
     assert email.from.is_a?(Array)

test/models/application_user_claim_test.rb

@@ -0,0 +1,78 @@
+require "test_helper"
+
+class ApplicationUserClaimTest < ActiveSupport::TestCase
+  def setup
+    @user = users(:bob)
+    @application = applications(:another_app)
+  end
+
+  test "should create valid application user claim" do
+    claim = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: { "role": "admin" }
+    )
+    assert claim.valid?
+    assert claim.save
+  end
+
+  test "should enforce uniqueness of user per application" do
+    ApplicationUserClaim.create!(
+      user: @user,
+      application: @application,
+      custom_claims: { "role": "admin" }
+    )
+
+    duplicate = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: { "role": "user" }
+    )
+
+    assert_not duplicate.valid?
+    assert_includes duplicate.errors[:user_id], "has already been taken"
+  end
+
+  test "parsed_custom_claims returns hash" do
+    claim = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: { "role": "admin", "level": 5 }
+    )
+
+    parsed = claim.parsed_custom_claims
+    assert_equal "admin", parsed["role"]
+    assert_equal 5, parsed["level"]
+  end
+
+  test "parsed_custom_claims returns empty hash when nil" do
+    claim = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: nil
+    )
+
+    assert_equal({}, claim.parsed_custom_claims)
+  end
+
+  test "should not allow reserved OIDC claim names" do
+    claim = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: { "groups": ["admin"], "role": "user" }
+    )
+
+    assert_not claim.valid?
+    assert_includes claim.errors[:custom_claims], "cannot override reserved OIDC claims: groups"
+  end
+
+  test "should allow non-reserved claim names" do
+    claim = ApplicationUserClaim.new(
+      user: @user,
+      application: @application,
+      custom_claims: { "kavita_groups": ["admin"], "role": "user" }
+    )
+
+    assert claim.valid?
+  end
+end

test/services/oidc_jwt_service_test.rb

@@ -14,7 +14,8 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
     assert token.length > 100, "Token should be substantial"
     assert token.include?('.')
 
-    decoded = JWT.decode(token, nil, true)
+    # Decode without verification for testing the payload
+    decoded = JWT.decode(token, nil, false).first
     assert_equal @application.client_id, decoded['aud'], "Should have correct audience"
     assert_equal @user.id.to_s, decoded['sub'], "Should have correct subject"
     assert_equal @user.email_address, decoded['email'], "Should have correct email"
@@ -22,16 +23,16 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
     assert_equal @user.email_address, decoded['preferred_username'], "Should have preferred username"
     assert_equal @user.email_address, decoded['name'], "Should have name"
     assert_equal "https://localhost:3000", decoded['iss'], "Should have correct issuer"
-    assert_equal Time.now.to_i + 3600, decoded['exp'], "Should have correct expiration"
+    assert_in_delta Time.current.to_i + 3600, decoded['exp'], 5, "Should have correct expiration"
   end
 
   test "should handle nonce in id token" do
     nonce = "test-nonce-12345"
     token = @service.generate_id_token(@user, @application, nonce: nonce)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     assert_equal nonce, decoded['nonce'], "Should preserve nonce in token"
-    assert_equal Time.now.to_i + 3600, decoded['exp'], "Should have correct expiration with nonce"
+    assert_in_delta Time.current.to_i + 3600, decoded['exp'], 5, "Should have correct expiration with nonce"
   end
 
   test "should include groups in token when user has groups" do
@@ -39,17 +40,17 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
 
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     assert_includes decoded['groups'], "admin", "Should include user's groups"
   end
 
-  test "should include admin claim for admin users" do
+  test "admin claim should not be included in token" do
     @user.update!(admin: true)
 
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
-    assert_equal true, decoded['admin'], "Admin users should have admin claim"
+    decoded = JWT.decode(token, nil, false).first
+    refute decoded.key?('admin'), "Admin claim should not be included in ID tokens (use groups instead)"
   end
 
   test "should handle role-based claims when enabled" do
@@ -63,7 +64,7 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
 
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     assert_includes decoded['roles'], "editor", "Should include user's role"
   end
 
@@ -96,7 +97,7 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
 
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     assert_equal "Content Editor", decoded['role_display_name'], "Should include role display name"
     assert_includes decoded['role_permissions'], "read", "Should include read permission"
     assert_includes decoded['role_permissions'], "write", "Should include write permission"
@@ -107,7 +108,7 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
   test "should handle missing roles gracefully" do
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     refute_includes decoded, 'roles', "Should not have roles when not configured"
   end
 
@@ -260,7 +261,7 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
   test "should handle access token generation" do
     token = @service.generate_id_token(@user, @application)
 
-    decoded = JWT.decode(token, nil, true)
+    decoded = JWT.decode(token, nil, false).first
     refute_includes decoded.keys, 'email_verified'
     assert_equal @user.id.to_s, decoded['sub'], "Should decode subject correctly"
     assert_equal @application.client_id, decoded['aud'], "Should decode audience correctly"
@@ -291,4 +292,215 @@ class OidcJwtServiceTest < ActiveSupport::TestCase
     end
     assert_match /no key found/, error.message, "Should warn about missing private key"
   end
+
+  test "should include app-specific custom claims in token" do
+    # Use bob and another_app to avoid fixture conflicts
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Create app-specific claim
+    ApplicationUserClaim.create!(
+      user: user,
+      application: app,
+      custom_claims: { "app_groups": ["admin"], "library_access": "all" }
+    )
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    assert_equal ["admin"], decoded["app_groups"]
+    assert_equal "all", decoded["library_access"]
+  end
+
+  test "app-specific claims should override user and group claims" do
+    # Use bob and another_app to avoid fixture conflicts
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Add user to group with claims
+    group = groups(:admin_group)
+    group.update!(custom_claims: { "role": "viewer", "max_items": 10 })
+    user.groups << group
+
+    # Add user custom claims
+    user.update!(custom_claims: { "role": "editor", "theme": "dark" })
+
+    # Add app-specific claims (should override both)
+    ApplicationUserClaim.create!(
+      user: user,
+      application: app,
+      custom_claims: { "role": "admin", "app_specific": true }
+    )
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # App-specific claim should win
+    assert_equal "admin", decoded["role"]
+    # App-specific claim should be present
+    assert_equal true, decoded["app_specific"]
+    # User claim not overridden should still be present
+    assert_equal "dark", decoded["theme"]
+    # Group claim not overridden should still be present
+    assert_equal 10, decoded["max_items"]
+  end
+
+  test "should deep merge array claims from group and user" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Group has roles: ["user"]
+    group = groups(:admin_group)
+    group.update!(custom_claims: { "roles" => ["user"], "permissions" => ["read"] })
+    user.groups << group
+
+    # User adds roles: ["admin"]
+    user.update!(custom_claims: { "roles" => ["admin"], "permissions" => ["write"] })
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # Roles should be combined (not overwritten)
+    assert_equal 2, decoded["roles"].length
+    assert_includes decoded["roles"], "user"
+    assert_includes decoded["roles"], "admin"
+    # Permissions should also be combined
+    assert_equal 2, decoded["permissions"].length
+    assert_includes decoded["permissions"], "read"
+    assert_includes decoded["permissions"], "write"
+  end
+
+  test "should deep merge array claims from multiple groups" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # First group has roles: ["user"]
+    group1 = groups(:admin_group)
+    group1.update!(custom_claims: { "roles" => ["user"] })
+    user.groups << group1
+
+    # Second group has roles: ["moderator"]
+    group2 = Group.create!(name: "moderators", description: "Moderators group")
+    group2.update!(custom_claims: { "roles" => ["moderator"] })
+    user.groups << group2
+
+    # User adds roles: ["admin"]
+    user.update!(custom_claims: { "roles" => ["admin"] })
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # All roles should be combined
+    assert_equal 3, decoded["roles"].length
+    assert_includes decoded["roles"], "user"
+    assert_includes decoded["roles"], "moderator"
+    assert_includes decoded["roles"], "admin"
+  end
+
+  test "should remove duplicate values when merging arrays" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Group has roles: ["user", "reader"]
+    group = groups(:admin_group)
+    group.update!(custom_claims: { "roles" => ["user", "reader"] })
+    user.groups << group
+
+    # User also has "user" role (duplicate)
+    user.update!(custom_claims: { "roles" => ["user", "admin"] })
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # "user" should only appear once
+    assert_equal 3, decoded["roles"].length
+    assert_includes decoded["roles"], "user"
+    assert_includes decoded["roles"], "reader"
+    assert_includes decoded["roles"], "admin"
+  end
+
+  test "should override non-array values while merging arrays" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Group has roles array and max_items scalar
+    group = groups(:admin_group)
+    group.update!(custom_claims: { "roles" => ["user"], "max_items" => 10, "theme" => "light" })
+    user.groups << group
+
+    # User overrides max_items and theme, adds to roles
+    user.update!(custom_claims: { "roles" => ["admin"], "max_items" => 100, "theme" => "dark" })
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # Arrays should be combined
+    assert_equal 2, decoded["roles"].length
+    assert_includes decoded["roles"], "user"
+    assert_includes decoded["roles"], "admin"
+    # Scalar values should be overridden (user wins)
+    assert_equal 100, decoded["max_items"]
+    assert_equal "dark", decoded["theme"]
+  end
+
+  test "should deep merge nested hashes in claims" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Group has nested config
+    group = groups(:admin_group)
+    group.update!(custom_claims: {
+      "config" => {
+        "theme" => "light",
+        "notifications" => { "email" => true }
+      }
+    })
+    user.groups << group
+
+    # User adds to nested config
+    user.update!(custom_claims: {
+      "config" => {
+        "language" => "en",
+        "notifications" => { "sms" => true }
+      }
+    })
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # Nested hashes should be deep merged
+    assert_equal "light", decoded["config"]["theme"]
+    assert_equal "en", decoded["config"]["language"]
+    assert_equal true, decoded["config"]["notifications"]["email"]
+    assert_equal true, decoded["config"]["notifications"]["sms"]
+  end
+
+  test "app-specific claims should combine arrays with group and user claims" do
+    user = users(:bob)
+    app = applications(:another_app)
+
+    # Group has roles: ["user"]
+    group = groups(:admin_group)
+    group.update!(custom_claims: { "roles" => ["user"] })
+    user.groups << group
+
+    # User has roles: ["moderator"]
+    user.update!(custom_claims: { "roles" => ["moderator"] })
+
+    # App-specific has roles: ["app_admin"]
+    ApplicationUserClaim.create!(
+      user: user,
+      application: app,
+      custom_claims: { "roles" => ["app_admin"] }
+    )
+
+    token = @service.generate_id_token(user, app)
+    decoded = JWT.decode(token, nil, false).first
+
+    # All three sources should be combined
+    assert_equal 3, decoded["roles"].length
+    assert_includes decoded["roles"], "user"
+    assert_includes decoded["roles"], "moderator"
+    assert_includes decoded["roles"], "app_admin"
+  end
 end