ddns/ddns.go
2014-07-14 23:19:47 +02:00

152 lines
2.8 KiB
Go

package main
import (
"bufio"
"fmt"
"github.com/gin-gonic/gin"
"github.com/pboehm/ddns/connection"
"log"
"net"
"net/http"
"os"
"strings"
)
func HandleErr(err error) {
if err != nil {
log.Fatal(err)
}
}
func RunBackend() {
conn := connection.OpenConnection()
defer conn.Close()
fmt.Printf("OK\tDDNS Go Backend\n")
bio := bufio.NewReader(os.Stdin)
for {
line, _, err := bio.ReadLine()
HandleErr(err)
parts := strings.Split(string(line), "\t")
if len(parts) == 6 {
query_name := parts[1]
fqdn_parts := strings.Split(query_name, ".")
query_class := parts[2]
query_id := parts[4]
if len(fqdn_parts) > 0 {
if conn.HostExist(fqdn_parts[0]) {
host := conn.GetHost(fqdn_parts[0])
record := "A"
if !host.IsIPv4() {
record = "AAAA"
}
fmt.Printf("DATA\t%s\t%s\t%s\t10\t%s\t%s\n",
query_name, query_class, record, query_id, host.Ip)
}
}
}
fmt.Printf("END\n")
}
}
func RunWebService() {
conn := connection.OpenConnection()
defer conn.Close()
r := gin.Default()
r.GET("/new/:hostname", func(c *gin.Context) {
hostname := c.Params.ByName("hostname")
if conn.HostExist(hostname) {
c.String(403, "This hostname has already been registered.")
return
}
host := &connection.Host{Hostname: hostname, Ip: "127.0.0.1"}
host.GenerateAndSetToken()
conn.SaveHost(host)
c.String(200, fmt.Sprintf(
"Go to /update/%s/%s for updating your IP address",
host.Hostname, host.Token))
})
r.GET("/update/:hostname/:token", func(c *gin.Context) {
hostname := c.Params.ByName("hostname")
token := c.Params.ByName("token")
if !conn.HostExist(hostname) {
c.String(404,
"This hostname has not been registered or is expired.")
return
}
host := conn.GetHost(hostname)
if host.Token != token {
c.String(403,
"You have supplied the wrong token to manipulate this host")
return
}
ip, err := GetRemoteAddr(c.Req)
if err != nil {
c.String(500, "You sender IP address is not in the right format")
}
host.Ip = ip
conn.SaveHost(host)
c.String(200, fmt.Sprintf("Your current IP is %s", ip))
})
r.Run(":8080")
}
// Get the Remote Address of the client. At First we try to get the
// X-Forwarded-For Header which holds the IP if we are behind a proxy,
// otherwise the RemoteAddr is used
func GetRemoteAddr(req *http.Request) (string, error) {
header_data, ok := req.Header["X-Forwarded-For"]
if ok {
return header_data[0], nil
} else {
ip, _, err := net.SplitHostPort(req.RemoteAddr)
return ip, err
}
}
func main() {
if len(os.Args) < 2 {
usage()
}
cmd := os.Args[1]
switch cmd {
case "backend":
log.Printf("Starting PDNS Backend\n")
RunBackend()
case "web":
log.Printf("Starting Web Service\n")
RunWebService()
default:
usage()
}
}
func usage() {
log.Fatal("Usage: ./ddns [backend|web]")
}