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February 5, 2021 11:34
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find out subdomain using golang :)
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| package main | |
| import ( | |
| "bufio" | |
| "errors" | |
| "flag" | |
| "fmt" | |
| "os" | |
| "github.com/miekg/dns" | |
| ) | |
| type empty struct{} | |
| type result struct { | |
| IPAddress string | |
| Hostname string | |
| } | |
| func main() { | |
| var ( | |
| flDomain = flag.String("d", "", "The Domain to perform guessing against") | |
| flWordlist = flag.String("w", "", "The wordlist use for guessing") | |
| flWorkerCount = flag.Int("c", 1000, "The ammount of workers to use") | |
| flServerAddr = flag.String("s", "8.8.8.8:53", "The dns Server to use") | |
| ) | |
| flag.Parse() | |
| checkArgs(flDomain, flWordlist) | |
| // fmt.Println(*flWorkerCount, *flServerAddr) | |
| var results []result | |
| fqdns := make(chan string, *flWorkerCount) | |
| gather := make(chan []result) | |
| tracker := make(chan empty) | |
| fh, err := os.Open(*flWordlist) | |
| if err != nil { | |
| panic(err) | |
| } | |
| defer fh.Close() | |
| scanner := bufio.NewScanner(fh) | |
| for i := 0; i < *flWorkerCount; i++ { | |
| go worker(tracker, fqdns, gather, *flServerAddr) | |
| } | |
| for scanner.Scan() { | |
| fqdns <- fmt.Sprintf("%s.%s", scanner.Text(), *flDomain) | |
| } | |
| go func() { | |
| for r := range gather { | |
| results = append(results, r...) | |
| } | |
| var e empty | |
| tracker <- e | |
| }() | |
| close(fqdns) | |
| for i := 0; i < *flWorkerCount; i++ { | |
| <-tracker | |
| } | |
| close(gather) | |
| <-tracker | |
| for _, r := range results { | |
| fmt.Printf("%s\t%s\n", r.Hostname, r.IPAddress) | |
| } | |
| } | |
| // returns list of ip address | |
| func lookupA(fqdn, serverAddr string) ([]string, error) { | |
| var m dns.Msg | |
| var ips []string | |
| m.SetQuestion(dns.Fqdn(fqdn), dns.TypeA) | |
| in, err := dns.Exchange(&m, serverAddr) | |
| if err != nil { | |
| return ips, err | |
| } | |
| if len(in.Answer) < 1 { | |
| return ips, errors.New("no answer") | |
| } | |
| for _, answer := range in.Answer { | |
| if a, ok := answer.(*dns.A); ok { | |
| ips = append(ips, a.A.String()) | |
| } | |
| } | |
| return ips, nil | |
| } | |
| // returns a list of hostnames | |
| func lookupCNAME(fqdn, serverAddr string) ([]string, error) { | |
| var m dns.Msg | |
| var fqdns []string | |
| m.SetQuestion(dns.Fqdn(fqdn), dns.TypeCNAME) | |
| in, err := dns.Exchange(&m, serverAddr) | |
| if err != nil { | |
| return fqdns, err | |
| } | |
| if len(in.Answer) < 1 { | |
| return fqdns, errors.New("no answer") | |
| } | |
| for _, answer := range in.Answer { | |
| if c, ok := answer.(*dns.CNAME); ok { | |
| fqdns = append(fqdns, c.Target) | |
| } | |
| } | |
| return fqdns, nil | |
| } | |
| func lookup(fqdn, serverAddr string) []result { | |
| var results []result | |
| var cfqdn = fqdn | |
| for { | |
| cnames, err := lookupCNAME(cfqdn, serverAddr) | |
| if err == nil && len(cnames) > 0 { | |
| cfqdn = cnames[0] | |
| continue // we hae to process the next CNAME | |
| } | |
| ips, err := lookupA(cfqdn, serverAddr) | |
| if err != nil { | |
| break // there are no records for this host name | |
| } | |
| for _, ip := range ips { | |
| results = append(results, result{IPAddress: ip, Hostname: fqdn}) | |
| } | |
| break // we have processed all the requests | |
| } | |
| return results | |
| } | |
| // worker function | |
| func worker(tracker chan empty, fqdns chan string, gather chan []result, serverAddr string) { | |
| for fqdn := range fqdns { | |
| results := lookup(fqdn, serverAddr) | |
| if len(results) > 0 { | |
| gather <- results | |
| } | |
| } | |
| var e empty | |
| tracker <- e | |
| } | |
| func checkArgs(d *string, w *string) { | |
| if *d == "" || *w == "" { | |
| fmt.Println("domain and wordlist are required") | |
| os.Exit(1) | |
| } | |
| } |
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find sub domain using golang :)