fix: security improvement (#62)

.github/workflows/ci.yml

@@ -10,7 +10,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go: [ '1.15.x', '1.16.x', '1.17.x' ]
+        go: [ '1.15.x', '1.16.x', '1.17.x', '1.18.x' ]
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master

swagger.go

@@ -122,6 +122,10 @@ func Handler(configFns ...func(*Config)) http.HandlerFunc {
 	var re = regexp.MustCompile(`^(.*/)([^?].*)?[?|.]*$`)
 
 	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
 		matches := re.FindStringSubmatch(r.RequestURI)
 		path := matches[2]
 
@@ -155,7 +159,7 @@ func Handler(configFns ...func(*Config)) http.HandlerFunc {
 			}
 			_, _ = w.Write([]byte(doc))
 		case "":
-			http.Redirect(w, r, h.Prefix+"index.html", 301)
+			http.Redirect(w, r, h.Prefix+"index.html", http.StatusMovedPermanently)
 		default:
 			h.ServeHTTP(w, r)
 		}

swagger_test.go

@@ -43,35 +43,36 @@ func TestWrapHandler(t *testing.T) {
 
 	router.Handle("/", Handler(DocExpansion("none"), DomID("#swagger-ui")))
 
-	w1 := performRequest("GET", "/index.html", router)
-	assert.Equal(t, 200, w1.Code)
+	w1 := performRequest(http.MethodGet, "/index.html", router)
+	assert.Equal(t, http.StatusOK, w1.Code)
 	assert.Equal(t, w1.Header()["Content-Type"][0], "text/html; charset=utf-8")
 
-	w2 := performRequest("GET", "/doc.json", router)
-	assert.Equal(t, 500, w2.Code)
+	assert.Equal(t, http.StatusInternalServerError, performRequest(http.MethodGet, "/doc.json", router).Code)
 
 	swag.Register(swag.Name, &mockedSwag{})
-	w2 = performRequest("GET", "/doc.json", router)
-	assert.Equal(t, 200, w2.Code)
+	w2 := performRequest(http.MethodGet, "/doc.json", router)
+	assert.Equal(t, http.StatusOK, w2.Code)
 	assert.Equal(t, "application/json; charset=utf-8", w2.Header().Get("content-type"))
 
-	w3 := performRequest("GET", "/favicon-16x16.png", router)
-	assert.Equal(t, 200, w3.Code)
+	w3 := performRequest(http.MethodGet, "/favicon-16x16.png", router)
+	assert.Equal(t, http.StatusOK, w3.Code)
 	assert.Equal(t, w3.Header()["Content-Type"][0], "image/png")
 
-	w4 := performRequest("GET", "/swagger-ui.css", router)
-	assert.Equal(t, 200, w4.Code)
+	w4 := performRequest(http.MethodGet, "/swagger-ui.css", router)
+	assert.Equal(t, http.StatusOK, w4.Code)
 	assert.Equal(t, w4.Header()["Content-Type"][0], "text/css; charset=utf-8")
 
-	w5 := performRequest("GET", "/swagger-ui-bundle.js", router)
-	assert.Equal(t, 200, w5.Code)
+	w5 := performRequest(http.MethodGet, "/swagger-ui-bundle.js", router)
+	assert.Equal(t, http.StatusOK, w5.Code)
 	assert.Equal(t, w5.Header()["Content-Type"][0], "application/javascript")
 
-	w6 := performRequest("GET", "/notfound", router)
-	assert.Equal(t, 404, w6.Code)
+	assert.Equal(t, http.StatusNotFound, performRequest(http.MethodGet, "/notfound", router).Code)
 
-	w7 := performRequest("GET", "/", router)
-	assert.Equal(t, 301, w7.Code)
+	assert.Equal(t, 301, performRequest(http.MethodGet, "/", router).Code)
+
+	assert.Equal(t, http.StatusMethodNotAllowed, performRequest(http.MethodPost, "/swagger/index.html", router).Code)
+
+	assert.Equal(t, http.StatusMethodNotAllowed, performRequest(http.MethodPut, "/swagger/index.html", router).Code)
 }
 
 func performRequest(method, target string, h http.Handler) *httptest.ResponseRecorder {