mirror of
https://github.com/andwati/dns-resolver.git
synced 2026-10-18 02:32:52 +00:00
34 lines
712 B
Go
34 lines
712 B
Go
package dns
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import (
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"encoding/binary"
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"strings"
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)
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type DNSQuestion struct {
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QName string
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QType uint16
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QClass uint16
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}
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// convert dns question into a byte slice
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func (q *DNSQuestion) Serialize() []byte {
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buf := EncodeQName(q.QName)
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question := make([]byte, 4)
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binary.BigEndian.PutUint16(question[0:2], q.QType)
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binary.BigEndian.PutUint16(question[2:4], q.QClass)
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return append(buf, question...)
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}
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// encode a domain name to dns format
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func EncodeQName(domain string) []byte {
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parts := strings.Split(domain, ".")
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var encoded []byte
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for _, part := range parts {
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encoded = append(encoded, byte(len(part)))
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encoded = append(encoded, part...)
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}
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encoded = append(encoded, 0)
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return encoded
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}
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