func (dnsconf *dNSConfig) GetNameServers() (addrs []net.IP, err error) {
netshCmd := exec.Command("netsh", "interface", "ip", "show", "dnsservers", dnsconf.iface.Name)
outputbuf, err := netshCmd.CombinedOutput()
if err != nil {
return nil, err
}
output := bytes.NewBuffer(outputbuf).String()
scanner := bufio.NewScanner(strings.NewReader(output))
for scanner.Scan() {
line := scanner.Text()
scannerLine := bufio.NewScanner(strings.NewReader(line))
scannerLine.Split(bufio.ScanWords)
var lineArr []string
for scannerLine.Scan() {
lineArr = append(lineArr, scannerLine.Text())
}
//empty line
if len(lineArr) == 0 {
continue
}
for _, addr := range lineArr {
err = helpers.CheckIP(addr)
if err == nil {
addrs = append(addrs, net.ParseIP(addr))
}
err = nil
}
}
return addrs, err
}
func addNameServers(c *cli.Context) {
var addrs []net.IP
for _, addr := range c.Args() {
err := helpers.CheckIP(addr)
if err != nil {
log.Fatal(err)
}
addrs = append(addrs, net.ParseIP(addr))
}
err := dnsconf.AddNameServers(addrs)
if err != nil {
log.Fatal(err)
} else {
log.Println("DNS servers added successfully")
}
}
// GetNameServers consume resolv.conf path and returns current host dns servers
// addresses.
func GetNameServers(filename string) (addrs []net.IP, err error) {
file, err := os.Open(filename)
if err != nil {
return nil, err
}
defer file.Close()
scanner := bufio.NewScanner(file)
for scanner.Scan() {
line := scanner.Text()
scannerLine := bufio.NewScanner(strings.NewReader(line))
scannerLine.Split(bufio.ScanWords)
var lineArr []string
for scannerLine.Scan() {
lineArr = append(lineArr, scannerLine.Text())
}
//empty line
if len(lineArr) == 0 {
continue
}
switch lineArr[0] {
case "nameserver": // add one name server
if len(lineArr) > 1 {
err = helpers.CheckIP(lineArr[1])
if err != nil {
return addrs, err
}
addrs = append(addrs, net.ParseIP(lineArr[1]))
}
}
}
return addrs, err
}
