5387c162c9
Full implementation, DNS (and in the future DNSSEC). Returns answer in a hopefully standards compliant way. Testing with my miek.nl zone are included as well. This should correctly handle nodata, nxdomain and cnames.
75 lines
1.8 KiB
Go
75 lines
1.8 KiB
Go
package file
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import "github.com/miekg/dns"
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// Result is the result of a Lookup
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type Result int
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const (
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Success Result = iota
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NameError
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NoData // aint no offical NoData return code.
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)
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// Lookup looks up qname and qtype in the zone, when do is true DNSSEC are included as well.
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// Two sets of records are returned, one for the answer and one for the additional section.
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func (z *Zone) Lookup(qname string, qtype uint16, do bool) ([]dns.RR, []dns.RR, Result) {
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// TODO(miek): implement DNSSEC
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var rr dns.RR
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mk, known := dns.TypeToRR[qtype]
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if !known {
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return nil, nil, NameError
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// Uhm...?
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// rr = new(RFC3597)
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} else {
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rr = mk()
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}
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if qtype == dns.TypeSOA {
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return z.lookupSOA(do)
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}
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rr.Header().Name = qname
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elem := z.Tree.Get(rr)
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if elem == nil {
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return []dns.RR{z.SOA}, nil, NameError
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}
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rrs := elem.Types(dns.TypeCNAME)
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if len(rrs) > 0 { // should only ever be 1 actually; TODO(miek) check for this?
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// lookup target from the cname
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rr.Header().Name = rrs[0].(*dns.CNAME).Target
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elem := z.Tree.Get(rr)
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if elem == nil {
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return rrs, nil, Success
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}
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return rrs, elem.All(), Success
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}
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rrs = elem.Types(qtype)
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if len(rrs) == 0 {
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return []dns.RR{z.SOA}, nil, NoData
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}
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// Need to check sub-type on RRSIG records to only include the correctly
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// typed ones.
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return rrs, nil, Success
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}
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func (z *Zone) lookupSOA(do bool) ([]dns.RR, []dns.RR, Result) {
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return []dns.RR{z.SOA}, nil, Success
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}
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// signatureForSubType range through the signature and return the correct
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// ones for the subtype.
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func (z *Zone) signatureForSubType(rrs []dns.RR, subtype uint16, do bool) []dns.RR {
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if !do {
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return nil
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}
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sigs := []dns.RR{}
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for _, sig := range rrs {
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if s, ok := sig.(*dns.RRSIG); ok {
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if s.TypeCovered == subtype {
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sigs = append(sigs, s)
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}
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}
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}
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return sigs
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}
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