feat: add option to run tinyauth on a top-level domain (#710)

* Add TINYAUTH_AUTH_SUBDOMAINSENABLED option

Setting it to false allows to use Tinyauth on top-level domain only,
but forbids automatic cross-app authentication using Traefik/Nginx.

* fix: inform services and controllers if subdomain cookie domain is enabled

* chore: rabbit feedback

* fix: deny ip addresses for standalone domain

---------

Co-authored-by: Stavros <steveiliop56@gmail.com>

internal/bootstrap/app_bootstrap.go

@@ -104,7 +104,13 @@ func (app *BootstrapApp) Setup() error {
 	}
 
 	// Get cookie domain
-	cookieDomain, err := utils.GetCookieDomain(app.context.appUrl)
+	cookieDomainResolver := utils.GetCookieDomain
+	if !app.config.Auth.SubdomainsEnabled {
+		tlog.App.Info().Msg("Subdomains disabled, automatic authentication for proxied apps will not work")
+		cookieDomainResolver = utils.GetStandaloneCookieDomain
+	}
+
+	cookieDomain, err := cookieDomainResolver(app.context.appUrl)
 
 	if err != nil {
 		return err

internal/bootstrap/router_bootstrap.go

@@ -84,6 +84,7 @@ func (app *BootstrapApp) setupRouter() (*gin.Engine, error) {
 		RedirectCookieName:     app.context.redirectCookieName,
 		CookieDomain:           app.context.cookieDomain,
 		OAuthSessionCookieName: app.context.oauthSessionCookieName,
+		SubdomainsEnabled:      app.config.Auth.SubdomainsEnabled,
 	}, apiRouter, app.services.authService)
 
 	oauthController.SetupRoutes()

internal/bootstrap/service_bootstrap.go

@@ -100,6 +100,7 @@ func (app *BootstrapApp) initServices(queries *repository.Queries) (Services, er
 		SessionCookieName:  app.context.sessionCookieName,
 		IP:                 app.config.Auth.IP,
 		LDAPGroupsCacheTTL: app.config.LDAP.GroupCacheTTL,
+		SubdomainsEnabled:  app.config.Auth.SubdomainsEnabled,
 	}, services.ldapService, queries, services.oauthBrokerService)
 
 	err = authService.Init()

internal/controller/oauth_controller.go

@@ -26,6 +26,7 @@ type OAuthControllerConfig struct {
 	SecureCookie           bool
 	AppURL                 string
 	CookieDomain           string
+	SubdomainsEnabled      bool
 }
 
 type OAuthController struct {
@@ -105,7 +106,7 @@ func (controller *OAuthController) oauthURLHandler(c *gin.Context) {
 		return
 	}
 
-	c.SetCookie(controller.config.OAuthSessionCookieName, sessionId, int(time.Hour.Seconds()), "/", fmt.Sprintf(".%s", controller.config.CookieDomain), controller.config.SecureCookie, true)
+	c.SetCookie(controller.config.OAuthSessionCookieName, sessionId, int(time.Hour.Seconds()), "/", controller.getCookieDomain(), controller.config.SecureCookie, true)
 
 	c.JSON(200, gin.H{
 		"status":  200,
@@ -135,7 +136,7 @@ func (controller *OAuthController) oauthCallbackHandler(c *gin.Context) {
 		return
 	}
 
-	c.SetCookie(controller.config.OAuthSessionCookieName, "", -1, "/", fmt.Sprintf(".%s", controller.config.CookieDomain), controller.config.SecureCookie, true)
+	c.SetCookie(controller.config.OAuthSessionCookieName, "", -1, "/", controller.getCookieDomain(), controller.config.SecureCookie, true)
 
 	oauthPendingSession, err := controller.auth.GetOAuthPendingSession(sessionIdCookie)
 
@@ -283,3 +284,10 @@ func (controller *OAuthController) isOidcRequest(params service.OAuthURLParams)
 		params.ClientID != "" &&
 		params.RedirectURI != ""
 }
+
+func (controller *OAuthController) getCookieDomain() string {
+	if controller.config.SubdomainsEnabled {
+		return "." + controller.config.CookieDomain
+	}
+	return controller.config.CookieDomain
+}

internal/model/config.go

@@ -18,6 +18,7 @@ func NewDefaultConfiguration() *Config {
 			Address: "0.0.0.0",
 		},
 		Auth: AuthConfig{
+			SubdomainsEnabled:  true,
 			SessionExpiry:      86400, // 1 day
 			SessionMaxLifetime: 0,     // disabled
 			LoginTimeout:       300,   // 5 minutes
@@ -102,6 +103,7 @@ type ServerConfig struct {
 type AuthConfig struct {
 	IP                 IPConfig                  `description:"IP whitelisting config options." yaml:"ip"`
 	Users              []string                  `description:"Comma-separated list of users (username:hashed_password)." yaml:"users"`
+	SubdomainsEnabled  bool                      `description:"Enable subdomains support." yaml:"subdomainsEnabled"`
 	UserAttributes     map[string]UserAttributes `description:"Map of per-user OIDC attributes (username -> attributes)." yaml:"userAttributes"`
 	UsersFile          string                    `description:"Path to the users file." yaml:"usersFile"`
 	SecureCookie       bool                      `description:"Enable secure cookies." yaml:"secureCookie"`

internal/service/auth_service.go

@@ -84,6 +84,7 @@ type AuthServiceConfig struct {
 	SessionCookieName  string
 	IP                 model.IPConfig
 	LDAPGroupsCacheTTL int
+	SubdomainsEnabled  bool
 }
 
 type AuthService struct {
@@ -397,6 +398,12 @@ func (auth *AuthService) DeleteSession(ctx context.Context, uuid string) (*http.
 		tlog.App.Warn().Err(err).Msg("Failed to delete session from database, proceeding to clear cookie anyway")
 	}
 
+	err = auth.queries.DeleteSession(ctx, uuid)
+
+	if err != nil {
+		return nil, err
+	}
+
 	return &http.Cookie{
 		Name:     auth.config.SessionCookieName,
 		Value:    "",
@@ -838,3 +845,10 @@ func (auth *AuthService) ClearRateLimitsTestingOnly() {
 	}
 	auth.loginMutex.Unlock()
 }
+
+func (auth *AuthService) getCookieDomain() string {
+	if auth.config.SubdomainsEnabled {
+		return "." + auth.config.CookieDomain
+	}
+	return auth.config.CookieDomain
+}

internal/utils/app_utils.go

@@ -22,7 +22,7 @@ func GetCookieDomain(u string) (string, error) {
 	host := parsed.Hostname()
 
 	if netIP := net.ParseIP(host); netIP != nil {
-		return "", errors.New("IP addresses not allowed")
+		return "", errors.New("ip addresses not allowed")
 	}
 
 	parts := strings.Split(host, ".")
@@ -47,6 +47,27 @@ func GetCookieDomain(u string) (string, error) {
 	return domain, nil
 }
 
+func GetStandaloneCookieDomain(u string) (string, error) {
+	parsed, err := url.Parse(u)
+	if err != nil {
+		return "", err
+	}
+
+	host := parsed.Hostname()
+
+	if netIP := net.ParseIP(host); netIP != nil {
+		return "", errors.New("ip addresses not allowed")
+	}
+
+	parts := strings.Split(host, ".")
+
+	if len(parts) < 2 {
+		return "", errors.New("invalid app url")
+	}
+
+	return host, nil
+}
+
 func ParseFileToLine(content string) string {
 	lines := strings.Split(content, "\n")
 	users := make([]string, 0)

internal/utils/app_utils_test.go

@@ -30,7 +30,7 @@ func TestGetRootDomain(t *testing.T) {
 	// IP address
 	domain = "http://10.10.10.10"
 	_, err = utils.GetCookieDomain(domain)
-	assert.ErrorContains(t, err, "IP addresses not allowed")
+	assert.ErrorContains(t, err, "ip addresses not allowed")
 
 	// Invalid URL
 	domain = "http://[::1]:namedport"
@@ -180,3 +180,48 @@ func TestIsRedirectSafe(t *testing.T) {
 	result = utils.IsRedirectSafe(redirectURL, domain)
 	assert.False(t, result)
 }
+
+func TestGetStandaloneCookieDomain(t *testing.T) {
+	// Normal case
+	domain := "http://tinyauth.app"
+	expected := "tinyauth.app"
+	result, err := utils.GetStandaloneCookieDomain(domain)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, result)
+
+	// URL with subdomain (full hostname is returned, no subdomain stripping)
+	domain = "http://sub.tinyauth.app"
+	expected = "sub.tinyauth.app"
+	result, err = utils.GetStandaloneCookieDomain(domain)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, result)
+
+	// URL with port (port should be stripped)
+	domain = "http://tinyauth.app:8080"
+	expected = "tinyauth.app"
+	result, err = utils.GetStandaloneCookieDomain(domain)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, result)
+
+	// URL with path
+	domain = "https://tinyauth.app/some/path"
+	expected = "tinyauth.app"
+	result, err = utils.GetStandaloneCookieDomain(domain)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, result)
+
+	// IP address
+	domain = "http://10.10.10.10"
+	_, err = utils.GetStandaloneCookieDomain(domain)
+	assert.ErrorContains(t, err, "ip addresses not allowed")
+
+	// Invalid domain (only TLD)
+	domain = "com"
+	_, err = utils.GetStandaloneCookieDomain(domain)
+	assert.ErrorContains(t, err, "invalid app url")
+
+	// Invalid URL
+	domain = "http://[::1]:namedport"
+	_, err = utils.GetStandaloneCookieDomain(domain)
+	assert.ErrorContains(t, err, "parse \"http://[::1]:namedport\": invalid port \":namedport\" after host")
+}