39 lines
926 B
Go
39 lines
926 B
Go
//go:build !windows
|
|
|
|
package dns
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"regexp"
|
|
)
|
|
|
|
var (
|
|
// nameserver xxx.xxx.xxx.xxx
|
|
nameserverPattern = regexp.MustCompile(`nameserver\s+(?P<ip>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})`)
|
|
)
|
|
|
|
func loadSystemResolver() (clients []dnsClient, err error) {
|
|
content, err := os.ReadFile("/etc/resolv.conf")
|
|
if err != nil {
|
|
err = fmt.Errorf("failed to read /etc/resolv.conf: %w", err)
|
|
return
|
|
}
|
|
nameservers := make([]string, 0)
|
|
for _, line := range nameserverPattern.FindAllStringSubmatch(string(content), -1) {
|
|
addr := line[1]
|
|
nameservers = append(nameservers, addr)
|
|
}
|
|
if len(nameservers) == 0 {
|
|
err = fmt.Errorf("no nameserver found in /etc/resolv.conf")
|
|
return
|
|
}
|
|
servers := make([]NameServer, 0, len(nameservers))
|
|
for _, addr := range nameservers {
|
|
servers = append(servers, NameServer{
|
|
Addr: fmt.Sprintf("%s:%d", addr, 53),
|
|
Net: "udp",
|
|
})
|
|
}
|
|
return transform(servers, nil), nil
|
|
}
|