1 files changed, 42 insertions, 0 deletions
diff --git a/src/cmd/go/internal/vcweb/insecure.go b/src/cmd/go/internal/vcweb/insecure.go
new file mode 100644
index 0000000..1d6af25
--- /dev/null
+++ b/src/cmd/go/internal/vcweb/insecure.go
@@ -0,0 +1,42 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package vcweb
+
+import (
+	"log"
+	"net/http"
+)
+
+// insecureHandler redirects requests to the same host and path but using the
+// "http" scheme instead of "https".
+type insecureHandler struct{}
+
+func (h *insecureHandler) Available() bool { return true }
+
+func (h *insecureHandler) Handler(dir string, env []string, logger *log.Logger) (http.Handler, error) {
+	// The insecure-redirect handler implementation doesn't depend or dir or env.
+	//
+	// The only effect of the directory is to determine which prefix the caller
+	// will strip from the request before passing it on to this handler.
+	return h, nil
+}
+
+func (h *insecureHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if req.Host == "" && req.URL.Host == "" {
+		http.Error(w, "no Host provided in request", http.StatusBadRequest)
+		return
+	}
+
+	// Note that if the handler is wrapped with http.StripPrefix, the prefix
+	// will remain stripped in the redirected URL, preventing redirect loops
+	// if the scheme is already "http".
+
+	u := *req.URL
+	u.Scheme = "http"
+	u.User = nil
+	u.Host = req.Host
+
+	http.Redirect(w, req, u.String(), http.StatusFound)
+}