diff --git a/Sense/server/app/sense/identity/http.go b/Sense/server/app/sense/identity/http.go
index 977eee0..6a3f00d 100644
--- a/Sense/server/app/sense/identity/http.go
+++ b/Sense/server/app/sense/identity/http.go
@@ -48,6 +48,21 @@ func Require(permission string, next http.Handler) http.Handler {
 	})
 }
 
+// RequireSameOriginFrame authenticates browser iframe navigation that cannot
+// attach the X-Product header used by API clients. Fetch Metadata keeps this
+// narrow: only a same-origin iframe navigation with a valid Sense session is
+// accepted.
+func RequireSameOriginFrame(permission string, next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		module := activeModule.Load()
+		if module == nil {
+			platform.WriteError(w, &platform.APIError{Status: http.StatusServiceUnavailable, Code: "identity_not_ready", Message: "身份服务尚未就绪"})
+			return
+		}
+		module.RequireSameOriginFrame(permission, next).ServeHTTP(w, r)
+	})
+}
+
 func PrincipalFromContext(ctx context.Context) (Principal, bool) {
 	principal, ok := ctx.Value(principalContextKey{}).(Principal)
 	return principal, ok
@@ -84,6 +99,28 @@ func (m *Module) Require(permission string, next http.Handler) http.Handler {
 	}))
 }
 
+func (m *Module) RequireSameOriginFrame(permission string, next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("Sec-Fetch-Site") != "same-origin" ||
+			r.Header.Get("Sec-Fetch-Mode") != "navigate" ||
+			r.Header.Get("Sec-Fetch-Dest") != "iframe" {
+			platform.WriteError(w, &platform.APIError{Status: http.StatusUnauthorized, Code: "unauthorized", Message: "登录状态无效"})
+			return
+		}
+		cookie, err := r.Cookie(sessionCookieName)
+		if err != nil {
+			platform.WriteError(w, &platform.APIError{Status: http.StatusUnauthorized, Code: "unauthorized", Message: "登录状态无效"})
+			return
+		}
+		principal, err := m.service.Authenticate(r.Context(), cookie.Value)
+		if err != nil || !HasPermission(principal.Role, permission) {
+			platform.WriteError(w, &platform.APIError{Status: http.StatusUnauthorized, Code: "unauthorized", Message: "登录状态无效"})
+			return
+		}
+		next.ServeHTTP(w, r.WithContext(context.WithValue(r.Context(), principalContextKey{}, principal)))
+	})
+}
+
 func (m *Module) bootstrap(w http.ResponseWriter, r *http.Request) {
 	var request struct {
 		Username    string `json:"username"`
@@ -220,3 +257,4 @@ func SecureCookieFromEnvironment(value string, memoryMode bool) bool {
 	}
 	return !strings.EqualFold(value, "false")
 }
+