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|
package dns
import (
"log"
"net"
"github.com/miekg/dns"
)
type Dns struct {
server dns.Server
config *dns.ClientConfig
}
func (d *Dns) ServeDNS(w dns.ResponseWriter, req *dns.Msg) {
var resp *dns.Msg
var err error
client := new(dns.Client)
req.RecursionDesired = true;
for _, upstream := range d.config.Servers {
resp, _, err = client.Exchange(req, net.JoinHostPort(upstream, d.config.Port))
if err == nil {
break
}
log.Printf("dns query: %s", err)
}
w.WriteMsg(resp)
}
func New() (*Dns, error) {
var d Dns
var err error
d.server = dns.Server{
Net: "udp",
ReusePort: true,
Handler: &d,
}
d.config, err = dns.ClientConfigFromFile("/etc/resolv.conf")
if err != nil {
log.Printf("reading resolve.conf: %s", err)
return nil, err
}
return &d, nil
}
func (d *Dns) Run() {
d.server.ListenAndServe()
}
|
