Add files

meshname.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"encoding/base32"
+	"fmt"
+	"net"
+	"strings"
+	"os"
+	"errors"
+)
+
+var domainZone = ".mesh.arpa"
+
+func reverse_lookup(target string) (string, error) {
+	ip := net.ParseIP(target)
+	if ip == nil {
+		return "", errors.New("Invalid IP address")
+	}
+	str := base32.StdEncoding.EncodeToString(ip)[0:26]
+	return strings.ToLower(str) + domainZone, nil
+}
+
+func lookup(target string)  (string, error) {
+	labels := strings.Split(target, ".")
+	if len(labels) < 3 || strings.HasSuffix(domainZone, target) {
+		return "", errors.New("Invalid domain")
+	}
+	subDomain := labels[len(labels) - 3]
+	if len(subDomain) != 26 {
+		return "", errors.New("Invalid subdomain length")
+	}
+	name := strings.ToUpper(subDomain) + "======"
+	data, err := base32.StdEncoding.DecodeString(name)
+	if err != nil {
+		return "", err
+	}
+	s := net.IP(data)
+	if s == nil {
+		return "", errors.New("Invalid IP address")
+	}
+	return s.String(), nil
+}
+
+func main() {
+	usage := "Usage:\n\nmeshname lookup DOMAIN\nmeshname reverse_lookup IP"
+	if len(os.Args) != 3 {
+		fmt.Println(usage)
+		return
+	}
+
+	action := os.Args[1]
+	target := os.Args[2]
+
+	switch action {
+	case "lookup":
+		result, err := lookup(target)
+		if err != nil {
+			fmt.Println("Error:", err)
+			return
+		}
+		fmt.Println(result)
+		return
+	case "reverse_lookup":
+		result, err := reverse_lookup(target)
+		if err != nil {
+			fmt.Println("Error:", err)
+			return
+		}
+		fmt.Println(result)
+		return
+	default:
+		fmt.Println(usage)
+		return
+	}
+}