added README

README.md

@@ -0,0 +1,32 @@
+# Cool dns 
+
+A simple dns server written in Go. It supports zonefile parsing, different zones based on IP and forwarding. 
+
+# Configuration
+
+Example config file
+```yaml
+zones:                      
+- zone: example.com.        # Fully qualified domain name of the zone
+  file: zonefile.txt        # Path to the zonefile to parse
+
+- zone: example.com.
+  file: zonefile2.txt
+  acl:                      # What IPs can query the zone
+    - lan
+
+acl:                        # List of ip filter rules
+- name: vpn                 # Name of the rule
+  cidr: 10.0.0.0/24         # CIDR of the rule
+- name: lan
+  cidr: 192.168.0.0/16
+- name: local
+  cidr: 127.0.0.1/32
+
+forward:
+  acl:                      # What IPs are allowed
+    - vpn
+  server: "8.8.8.8:53"      # DNS server to forward to
+
+address: 0.0.0.0:8053       # What address and port to listen on
+```

config.yml

@@ -19,3 +19,5 @@ forward:
   acl:
     - vpn
   server: "8.8.8.8:53"
+
+address: 0.0.0.0:8053

coolDns.go

@@ -6,7 +6,6 @@ import (
 	"net"
 	"os"
 	"os/signal"
-	"strconv"
 	"strings"
 	"syscall"
 
@@ -27,6 +26,7 @@ type config struct {
 	Zones   []configZone  `yaml:"zones"`
 	ACL     []configACL   `yaml:"acl"`
 	Forward configForward `yaml:"forward"`
+	Address string        `yaml:"address"`
 }
 
 type configForward struct {
@@ -211,15 +211,15 @@ func createServer(zones zoneMap, config config, aclList map[string]*net.IPNet) *
 	return srv
 }
 
-func listenAndServer(server *dns.ServeMux) {
+func listenAndServer(server *dns.ServeMux, address string) {
 	go func() {
-		if err := dns.ListenAndServe(":"+strconv.Itoa(8053), "udp", server); err != nil {
+		if err := dns.ListenAndServe(address, "udp", server); err != nil {
 			log.Fatalf("Failed to set udp listener %s\n", err.Error())
 		}
 	}()
 
 	go func() {
-		if err := dns.ListenAndServe(":"+strconv.Itoa(8053), "tcp", server); err != nil {
+		if err := dns.ListenAndServe(address, "tcp", server); err != nil {
 			log.Fatalf("Failed to set tcp listener %s\n", err.Error())
 		}
 	}()
@@ -341,5 +341,6 @@ func main() {
 
 	server := createServer(zones, *config, aclList)
 
-	listenAndServer(server)
+	log.Printf("Start listening on udp %s and tcp %s\n", config.Address, config.Address)
+	listenAndServer(server, config.Address)
 }