50 lines
1.3 KiB
Go
50 lines
1.3 KiB
Go
package dns
|
|
|
|
import (
|
|
"context"
|
|
"net"
|
|
"strings"
|
|
|
|
"github.com/qdm12/gluetun/internal/constants"
|
|
)
|
|
|
|
// UseDNSInternally is to change the Go program DNS only
|
|
func (c *configurator) UseDNSInternally(ip net.IP) {
|
|
c.logger.Info("using DNS address %s internally", ip.String())
|
|
net.DefaultResolver = &net.Resolver{
|
|
PreferGo: true,
|
|
Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
|
|
d := net.Dialer{}
|
|
return d.DialContext(ctx, "udp", net.JoinHostPort(ip.String(), "53"))
|
|
},
|
|
}
|
|
}
|
|
|
|
// UseDNSSystemWide changes the nameserver to use for DNS system wide
|
|
func (c *configurator) UseDNSSystemWide(ip net.IP, keepNameserver bool) error {
|
|
c.logger.Info("using DNS address %s system wide", ip.String())
|
|
data, err := c.fileManager.ReadFile(string(constants.ResolvConf))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
s := strings.TrimSuffix(string(data), "\n")
|
|
lines := strings.Split(s, "\n")
|
|
if len(lines) == 1 && lines[0] == "" {
|
|
lines = nil
|
|
}
|
|
found := false
|
|
if !keepNameserver { // default
|
|
for i := range lines {
|
|
if strings.HasPrefix(lines[i], "nameserver ") {
|
|
lines[i] = "nameserver " + ip.String()
|
|
found = true
|
|
}
|
|
}
|
|
}
|
|
if !found {
|
|
lines = append(lines, "nameserver "+ip.String())
|
|
}
|
|
data = []byte(strings.Join(lines, "\n"))
|
|
return c.fileManager.WriteToFile(string(constants.ResolvConf), data)
|
|
}
|