43 lines
788 B
Go
43 lines
788 B
Go
//go:build !windows
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package dns
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import (
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"bufio"
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"fmt"
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"net/netip"
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"os"
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"strings"
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)
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const resolvConf = "/etc/resolv.conf"
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func dnsReadConfig() (servers []string, err error) {
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file, err := os.Open(resolvConf)
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if err != nil {
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err = fmt.Errorf("failed to read %s: %w", resolvConf, err)
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return
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}
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defer func() { _ = file.Close() }()
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scanner := bufio.NewScanner(file)
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for scanner.Scan() {
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line := scanner.Text()
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if len(line) > 0 && (line[0] == ';' || line[0] == '#') {
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// comment.
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continue
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}
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f := strings.Fields(line)
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if len(f) < 1 {
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continue
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}
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switch f[0] {
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case "nameserver": // add one name server
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if len(f) > 1 {
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if addr, err := netip.ParseAddr(f[1]); err == nil {
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servers = append(servers, addr.String())
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}
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}
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}
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}
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return
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}
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