From 2a991a3541ae5d567a5bf26c6fe60a7349bda9bb Mon Sep 17 00:00:00 2001 From: Tom DNetto Date: Fri, 18 Nov 2022 09:47:06 -0800 Subject: [PATCH] ipn/{localapi,ipnserver}: set a CSP for ServeHTMLStatus, refactor host check Signed-off-by: Tom DNetto --- ipn/ipnserver/server.go | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/ipn/ipnserver/server.go b/ipn/ipnserver/server.go index 1cc5037a8..33d39edcf 100644 --- a/ipn/ipnserver/server.go +++ b/ipn/ipnserver/server.go @@ -1031,11 +1031,14 @@ func (s *Server) localhostHandler(ci connIdentity) http.Handler { func (s *Server) ServeHTMLStatus(w http.ResponseWriter, r *http.Request) { // As this is only meant for debug, verify there's no DNS name being used to // access this. - if strings.IndexFunc(r.Host, unicode.IsLetter) != -1 { + if !strings.HasPrefix(r.Host, "localhost:") && strings.IndexFunc(r.Host, unicode.IsLetter) != -1 { http.Error(w, "invalid host", http.StatusForbidden) return } + w.Header().Set("Content-Security-Policy", `default-src 'none'; frame-ancestors 'none'; script-src 'none'; script-src-elem 'none'; script-src-attr 'none'`) + w.Header().Set("X-Frame-Options", "DENY") + w.Header().Set("X-Content-Type-Options", "nosniff") w.Header().Set("Content-Type", "text/html; charset=utf-8") st := s.b.Status() // TODO(bradfitz): add LogID and opts to st?