mirror of https://github.com/k3s-io/k3s
35 lines
1000 B
Go
35 lines
1000 B
Go
// Copyright (c) 2014 The SkyDNS Authors. All rights reserved.
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// Use of this source code is governed by The MIT License (MIT) that can be
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// found in the LICENSE file.
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package server
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import "github.com/miekg/dns"
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// exchangeMsg returns a new dns message based on name, type, bufsize and dnssec.
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func newExchangeMsg(name string, typ, bufsize uint16, dnssec bool) *dns.Msg {
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m := new(dns.Msg)
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m.SetQuestion(name, typ)
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m.SetEdns0(bufsize, dnssec)
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return m
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}
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// exchangeWithRetry sends message m to server, but retries on ServerFailure.
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func exchangeWithRetry(c *dns.Client, m *dns.Msg, server string) (*dns.Msg, error) {
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r, _, err := c.Exchange(m, server)
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if err == nil && r.Rcode == dns.RcodeServerFailure {
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// redo the query
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r, _, err = c.Exchange(m, server)
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}
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return r, err
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}
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func (s *server) randomNameserverID(id uint16) int {
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nsid := 0
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if s.config.NSRotate {
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// Use request Id for "random" nameserver selection.
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nsid = int(id) % len(s.config.Nameservers)
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}
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return nsid
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}
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