5301c5af5f
Cleanup the errors and removed deadcode along the way. The leaves some error laying around, mostly about commenting exported identifier. We should look hard if those really are needed.
58 lines
1.3 KiB
Go
58 lines
1.3 KiB
Go
package response
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import "github.com/miekg/dns"
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// Type is the type of the message
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type Type int
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const (
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// Success indicates a positive reply
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Success Type = iota
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// NameError is a NXDOMAIN in header, SOA in auth.
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NameError
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// NoData indicated name found, but not the type: NOERROR in header, SOA in auth.
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NoData
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// Delegation is a msg with a pointer to another nameserver: NOERROR in header, NS in auth, optionally fluff in additional (not checked).
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Delegation
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// OtherError indicated any other error: don't cache these.
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OtherError
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)
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// Classify classifies a message, it returns the Type.
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func Classify(m *dns.Msg) (Type, *dns.OPT) {
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opt := m.IsEdns0()
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if len(m.Answer) > 0 && m.Rcode == dns.RcodeSuccess {
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return Success, opt
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}
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soa := false
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ns := 0
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for _, r := range m.Ns {
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if r.Header().Rrtype == dns.TypeSOA {
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soa = true
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continue
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}
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if r.Header().Rrtype == dns.TypeNS {
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ns++
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}
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}
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// Check length of different sections, and drop stuff that is just to large? TODO(miek).
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if soa && m.Rcode == dns.RcodeSuccess {
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return NoData, opt
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}
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if soa && m.Rcode == dns.RcodeNameError {
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return NameError, opt
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}
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if ns > 0 && ns == len(m.Ns) && m.Rcode == dns.RcodeSuccess {
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return Delegation, opt
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}
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if m.Rcode == dns.RcodeSuccess {
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return Success, opt
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}
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return OtherError, opt
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}
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