54 lines
971 B
Go
54 lines
971 B
Go
package override
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import (
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"net"
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clog "github.com/coredns/coredns/plugin/pkg/log"
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"github.com/miekg/dns"
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)
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var log = clog.NewWithPlugin("override")
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type Rule struct {
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Search net.IP
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Override net.IP
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}
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type ResponseWrapper struct {
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dns.ResponseWriter
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Rules []Rule
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}
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func (r *ResponseWrapper) WriteMsg(res *dns.Msg) error {
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for _, r := range r.Rules {
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for _, rr := range res.Answer {
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overideRR(r, rr)
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}
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for _, rr := range res.Extra {
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overideRR(r, rr)
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}
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}
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return r.ResponseWriter.WriteMsg(res)
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}
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func overideRR(r Rule, rr dns.RR) {
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if rr.Header().Rrtype == dns.TypeA {
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a := rr.(*dns.A)
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if a.A.Equal(r.Search) {
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a.A = r.Override
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}
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} else if rr.Header().Rrtype == dns.TypeAAAA {
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a := rr.(*dns.AAAA)
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if a.AAAA.Equal(r.Search) {
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a.AAAA = r.Override
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}
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}
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}
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func (r *ResponseWrapper) Write(buf []byte) (int, error) {
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log.Warning("ResponseWrapper called with Write: not ensuring overide")
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return r.ResponseWriter.Write(buf)
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}
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