fix: harden login for MLPS requirements

server/internal/shared/middleware/security_headers_test.go

@@ -0,0 +1,75 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSecurityHeadersAddsNoStoreForSensitiveAuthPaths(t *testing.T) {
+	t.Parallel()
+
+	gin.SetMode(gin.TestMode)
+	router := gin.New()
+	router.Use(SecurityHeaders())
+	router.POST("/api/auth/login", func(c *gin.Context) {
+		c.Status(http.StatusOK)
+	})
+
+	req := httptest.NewRequest(http.MethodPost, "/api/auth/login", nil)
+	req.Header.Set("X-Forwarded-Proto", "https")
+	resp := httptest.NewRecorder()
+
+	router.ServeHTTP(resp, req)
+
+	require.Equal(t, http.StatusOK, resp.Code)
+	require.Equal(t, "nosniff", resp.Header().Get("X-Content-Type-Options"))
+	require.Equal(t, "DENY", resp.Header().Get("X-Frame-Options"))
+	require.Equal(t, "no-store", resp.Header().Get("Cache-Control"))
+	require.Equal(t, "no-cache", resp.Header().Get("Pragma"))
+	require.Equal(t, "max-age=31536000; includeSubDomains", resp.Header().Get("Strict-Transport-Security"))
+}
+
+func TestCORSWithConfigRejectsUnknownPreflightOrigin(t *testing.T) {
+	t.Parallel()
+
+	gin.SetMode(gin.TestMode)
+	router := gin.New()
+	router.Use(CORSWithConfig(CORSConfig{AllowedOrigins: []string{"https://admin.example.com"}}))
+	router.POST("/api/auth/login", func(c *gin.Context) {
+		c.Status(http.StatusOK)
+	})
+
+	req := httptest.NewRequest(http.MethodOptions, "/api/auth/login", nil)
+	req.Header.Set("Origin", "https://evil.example.com")
+	resp := httptest.NewRecorder()
+
+	router.ServeHTTP(resp, req)
+
+	require.Equal(t, http.StatusForbidden, resp.Code)
+	require.Empty(t, resp.Header().Get("Access-Control-Allow-Origin"))
+}
+
+func TestCORSWithConfigAllowsConfiguredOrigin(t *testing.T) {
+	t.Parallel()
+
+	gin.SetMode(gin.TestMode)
+	router := gin.New()
+	router.Use(CORSWithConfig(CORSConfig{AllowedOrigins: []string{"https://admin.example.com"}}))
+	router.POST("/api/auth/login", func(c *gin.Context) {
+		c.Status(http.StatusOK)
+	})
+
+	req := httptest.NewRequest(http.MethodOptions, "/api/auth/login", nil)
+	req.Header.Set("Origin", "https://admin.example.com")
+	resp := httptest.NewRecorder()
+
+	router.ServeHTTP(resp, req)
+
+	require.Equal(t, http.StatusNoContent, resp.Code)
+	require.Equal(t, "https://admin.example.com", resp.Header().Get("Access-Control-Allow-Origin"))
+	require.Equal(t, "Origin", resp.Header().Get("Vary"))
+}