Encrypt cookies

internal/server/login.go

@@ -40,7 +40,7 @@ func (s *Server) handleLoginPage(w http.ResponseWriter, r *http.Request) {
 	next := destination(r.URL.Query().Get("next"))
 
 	// Already logged in: say so rather than showing an empty form.
-	if lim, err := s.limitsFor(r, cookieCredential(r)); err == nil && !lim.Anonymous() {
+	if lim, err := s.limitsFor(r, s.cookieCredential(r)); err == nil && !lim.Anonymous() {
 		s.render(w, http.StatusOK, "login.html", loginPage{
 			page:      s.page(r, "Log in", false),
 			Next:      next,
@@ -82,7 +82,14 @@ func (s *Server) handleLogin(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	s.logIn(w, r, token, r.PostFormValue("persist") != "")
+	if err := s.logIn(w, r, token, r.PostFormValue("persist") != ""); err != nil {
+		// Sealing needs nothing but randomness, so this is the machine failing
+		// rather than the caller: say so instead of leaving them logged out
+		// with no explanation.
+		s.log.Error("sealing the session", "err", err)
+		s.fail(w, r, http.StatusInternalServerError, "Could not start a session.")
+		return
+	}
 	s.log.Info("logged in", "name", lim.Name, "ip", clientIP(r, s.cfg))
 
 	if wantsJSON(r) {