45 lines
1.2 KiB
Go
45 lines
1.2 KiB
Go
package main
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// Print the MX records of a domain
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// (c) Miek Gieben - 2011
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import (
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"dns"
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"dns/resolver"
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"os"
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"fmt"
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)
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func main() {
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r := new(resolver.Resolver)
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qr := r.NewQuerier()
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r.FromFile("/etc/resolv.conf")
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if len(os.Args) != 2 {
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fmt.Printf("%s DOMAIN\n", os.Args[0])
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os.Exit(1)
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}
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m := new(dns.Msg)
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m.MsgHdr.RecursionDesired = true //only set this bit
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m.Question = make([]dns.Question, 1)
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m.Question[0] = dns.Question{os.Args[1], dns.TypeMX, dns.ClassINET}
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qr <- resolver.Msg{m, nil}
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in := <-qr
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if in.Dns != nil {
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if in.Dns.Rcode != dns.RcodeSuccess {
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fmt.Printf(" *** invalid answer name %s after MX query for %s\n", os.Args[1], os.Args[1])
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os.Exit(1)
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}
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// Stuff must be in the answer section
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for _, a := range in.Dns.Answer {
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fmt.Printf("%v\n", a)
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}
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} else {
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fmt.Printf("*** error: %s\n", in.Error.String())
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}
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// Stop the resolver, send it a null mesg
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qr <- resolver.Msg{nil, nil}
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<-qr
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}
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