From 9c77160653e9ac87d051fe8a4eeffbaf7fd7307b Mon Sep 17 00:00:00 2001
From: Jirka Kremser <jiri.kremser@gmail.com>
Date: Tue, 7 Sep 2021 16:49:28 +0200
Subject: [PATCH] Issue #154: validation regexp + parsing the env var value
 correctly (prepared for ipv6)

Signed-off-by: Jirka Kremser <jiri.kremser@gmail.com>
---
 controllers/depresolver/depresolver_config.go | 45 +++++++++++++------
 .../depresolver/depresolver_validator.go      |  5 ++-
 2 files changed, 35 insertions(+), 15 deletions(-)

diff --git a/controllers/depresolver/depresolver_config.go b/controllers/depresolver/depresolver_config.go
index 84fee58b6a..f9088476d2 100644
--- a/controllers/depresolver/depresolver_config.go
+++ b/controllers/depresolver/depresolver_config.go
@@ -19,6 +19,7 @@ package depresolver
 
 import (
 	"fmt"
+	"net"
 	"strconv"
 	"strings"
 
@@ -127,15 +128,10 @@ func (dr *DependencyResolver) validateConfig(config *Config, recognizedDNSTypes
 			return err
 		}
 	}
-	// todo: this
-	// err = field(EdgeDNSServersKey, config.EdgeDNSServers).isNotEmpty().matchRegexps(hostNameRegex, ipAddressRegex).err
-	// if err != nil {
-	// 	return err
-	// }
-	// err = field(EdgeDNSServerPortKey, config.EdgeDNSServerPort).isHigherThanZero().err
-	// if err != nil {
-	// 	return err
-	// }
+	err = field(EdgeDNSServersKey, config.EdgeDNSServers).isNotEmpty().matchRegexps(hostNamesWithPortsRegex, ipAddressRegex).err
+	if err != nil {
+		return err
+	}
 	err = field(EdgeDNSZoneKey, config.EdgeDNSZone).isNotEmpty().matchRegexp(hostNameRegex).err
 	if err != nil {
 		return err
@@ -226,13 +222,34 @@ func parseMetricsAddr(metricsAddr string) (host string, port int, err error) {
 func parseEdgeDNSServers(serverList string) []utils.DNSServer {
 	var r []utils.DNSServer
 	chunks := strings.Split(serverList, ",")
-	// foreach chunk
+	var host, portStr string
+	var err error
 	for _, chunk := range chunks {
-		// if it contains colon
-		// chunk
+		switch strings.Count(chunk, ":") {
+		case 0: //ipv4 or domain
+			host = chunk
+			portStr = "53"
+		case 1: //ipv4 or domain
+			host, portStr, err = net.SplitHostPort(host)
+			if err != nil {
+				portStr = "53"
+			}
+		default: //ipv6
+			if net.ParseIP(chunk).To16() != nil {
+				host = chunk
+			} else {
+				host = chunk[:strings.LastIndex(chunk, ":")]
+				portStr = chunk[strings.LastIndex(chunk, ":")+1:]
+			}
+		}
+		var port int
+		port, err = strconv.Atoi(portStr)
+		if err != nil || port < 1 {
+			port = 53
+		}
 		r = append(r, utils.DNSServer{
-			Host: chunk,
-			Port: 53,
+			Host: host,
+			Port: port,
 		})
 	}
 	return r
diff --git a/controllers/depresolver/depresolver_validator.go b/controllers/depresolver/depresolver_validator.go
index f8e4f4dec2..3ab21461ca 100644
--- a/controllers/depresolver/depresolver_validator.go
+++ b/controllers/depresolver/depresolver_validator.go
@@ -26,8 +26,11 @@ import (
 const (
 	// hostNameRegex allows cloud region formats; e.g. af-south-1
 	geoTagRegex = "^[a-zA-Z\\-\\d]*$"
-	// hostNameRegex is valid as per RFC 1123 that allows hostname segments could start with a digit
+
+    // hostNameRegex is valid as per RFC 1123 that allows hostname segments could start with a digit
 	hostNameRegex = "^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\\-]*[a-zA-Z0-9])\\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\\-]*[A-Za-z0-9])$"
+	// hostnames are valid as per the previous regexp, it may also contain :123 port and multiple comma-separated entries are supported
+	hostNamesWithPortsRegex = "^((([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\\-]*[a-zA-Z0-9])\\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\\-]*[A-Za-z0-9])(:\\d{1,5})?,?)+[^,]$"
 	// ipAddressRegex matches valid IPv4 addresses
 	ipAddressRegex = "^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$"
 	// versionNumberRegex matches version in formats 0.1.2, v0.1.2, v0.1.2-alpha