92 lines
1.5 KiB
Go
92 lines
1.5 KiB
Go
package dns
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import (
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"errors"
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"fmt"
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"math/rand"
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"strings"
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"github.com/miekg/dns"
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)
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// Query records
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func (q *Query) Lookup() {
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for {
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// Create result
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result := &Result{
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Domain: q.Domain,
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Subdomain: q.Subdomain,
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}
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// Create message
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message := new(dns.Msg)
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// Set question
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switch q.IPv6 {
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case false:
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message.SetQuestion(dns.Fqdn(q.Subdomain), dns.TypeA)
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case true:
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message.SetQuestion(dns.Fqdn(q.Subdomain), dns.TypeAAAA)
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}
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// Choose random resolver
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resolver := q.Resolvers[rand.Intn(len(q.Resolvers))]
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// Query response
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resp, _, err := q.Client.Exchange(message, resolver)
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if err != nil {
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// Ratelimited
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if strings.ContainsAny(err.Error(), "i/o timeout") {
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continue
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}
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result.Error = err
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q.Results <- result
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return
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}
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// Store IPs
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var ips []string
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// Go through answers
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for _, answer := range resp.Answer {
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// Map record
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switch q.IPv6 {
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case false:
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record, ok := answer.(*dns.A)
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if !ok {
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continue
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}
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// Append IPv4
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ips = append(ips, record.A.String())
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case true:
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record, ok := answer.(*dns.AAAA)
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if !ok {
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continue
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}
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// Append IPv4
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ips = append(ips, record.AAAA.String())
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}
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}
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// No IPs found
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if len(ips) < 1 {
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result.Error = errors.New(fmt.Sprintf("No IPs found for %s", q.Domain))
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q.Results <- result
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return
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}
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// Send result
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switch q.IPv6 {
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case false:
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result.IPv4 = ips
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case true:
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result.IPv6 = ips
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}
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q.Results <- result
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return
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}
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}
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