From 1b15bee2b09df5b2c31edf6d6d594aa53ac9124c Mon Sep 17 00:00:00 2001
From: Aleksey Dmitrevskiy <ad@adguard.com>
Date: Wed, 6 Mar 2019 18:24:14 +0300
Subject: [PATCH] [change] control: add upstreams validation
---
control.go | 34 ++++++++++++++++++++++++++--------
1 file changed, 26 insertions(+), 8 deletions(-)
diff --git a/control.go b/control.go
index fb1cf0af..fe340ecd 100644
--- a/control.go
+++ b/control.go
@@ -322,15 +322,21 @@ func handleSetUpstreamConfig(w http.ResponseWriter, r *http.Request) {
return
}
+ for _, u := range newconfig.Upstreams {
+ if err = validateUpstream(u); err != nil {
+ httpError(w, http.StatusBadRequest, "%s can not be used as upstream cause: %s", u, err)
+ return
+ }
+ }
+
config.DNS.UpstreamDNS = defaultDNS
if len(newconfig.Upstreams) > 0 {
config.DNS.UpstreamDNS = newconfig.Upstreams
}
- // bootstrap servers are plain DNS only. We should return http error if there are tls:// https:// or sdns:// hosts in slice
+ // bootstrap servers are plain DNS only.
for _, host := range newconfig.BootstrapDNS {
- err := checkPlainDNS(host)
- if err != nil {
+ if err := checkPlainDNS(host); err != nil {
httpError(w, http.StatusBadRequest, "%s can not be used as bootstrap dns cause: %s", host, err)
return
}
@@ -345,26 +351,38 @@ func handleSetUpstreamConfig(w http.ResponseWriter, r *http.Request) {
httpUpdateConfigReloadDNSReturnOK(w, r)
}
+func validateUpstream(upstream string) error {
+ if strings.HasPrefix(upstream, "tls://") || strings.HasPrefix(upstream, "https://") || strings.HasPrefix(upstream, "sdns://") || strings.HasPrefix(upstream, "tcp://") {
+ return nil
+ }
+
+ if strings.Contains(upstream, "://") {
+ return fmt.Errorf("wrong protocol")
+ }
+
+ return checkPlainDNS(upstream)
+}
+
// checkPlainDNS checks if host is plain DNS
-func checkPlainDNS(host string) error {
+func checkPlainDNS(upstream string) error {
// Check if host is ip without port
- if net.ParseIP(host) != nil {
+ if net.ParseIP(upstream) != nil {
return nil
}
// Check if host is ip with port
- ip, port, err := net.SplitHostPort(host)
+ ip, port, err := net.SplitHostPort(upstream)
if err != nil {
return err
}
if net.ParseIP(ip) == nil {
- return fmt.Errorf("%s is not valid IP", ip)
+ return fmt.Errorf("%s is not a valid IP", ip)
}
_, err = strconv.ParseInt(port, 0, 64)
if err != nil {
- return fmt.Errorf("%s is not valid port: %s", port, err)
+ return fmt.Errorf("%s is not a valid port: %s", port, err)
}
return nil