package dnsfilter import ( "encoding/json" "fmt" "log" "net/http" "runtime" "strconv" "strings" "time" "github.com/AdguardTeam/AdguardDNS/dnsfilter" "github.com/coredns/coredns/plugin/pkg/response" "github.com/miekg/dns" "github.com/zfjagann/golang-ring" ) var logBuffer = ring.Ring{} type logEntry struct { Question *dns.Msg Answer *dns.Msg Result dnsfilter.Result Time time.Time Elapsed time.Duration IP string } func init() { logBuffer.SetCapacity(1000) } func logRequest(question *dns.Msg, answer *dns.Msg, result dnsfilter.Result, elapsed time.Duration, ip string) { entry := logEntry{ Question: question, Answer: answer, Result: result, Time: time.Now(), Elapsed: elapsed, IP: ip, } logBuffer.Enqueue(entry) } func handler(w http.ResponseWriter, r *http.Request) { values := logBuffer.Values() var data = []map[string]interface{}{} for _, value := range values { entry, ok := value.(logEntry) if !ok { continue } jsonentry := map[string]interface{}{ "reason": entry.Result.Reason.String(), "elapsed_ms": strconv.FormatFloat(entry.Elapsed.Seconds()*1000, 'f', -1, 64), "time": entry.Time.Format(time.RFC3339), "client": entry.IP, } question := map[string]interface{}{ "host": strings.ToLower(strings.TrimSuffix(entry.Question.Question[0].Name, ".")), "type": dns.Type(entry.Question.Question[0].Qtype).String(), "class": dns.Class(entry.Question.Question[0].Qclass).String(), } jsonentry["question"] = question status, _ := response.Typify(entry.Answer, time.Now().UTC()) jsonentry["status"] = status.String() if len(entry.Result.Rule) > 0 { jsonentry["rule"] = entry.Result.Rule } if entry.Answer != nil && len(entry.Answer.Answer) > 0 { var answers = []map[string]interface{}{} for _, k := range entry.Answer.Answer { header := k.Header() answer := map[string]interface{}{ "type": dns.TypeToString[header.Rrtype], "ttl": header.Ttl, } // try most common record types switch v := k.(type) { case *dns.A: answer["value"] = v.A case *dns.AAAA: answer["value"] = v.AAAA case *dns.MX: answer["value"] = fmt.Sprintf("%v %v", v.Preference, v.Mx) case *dns.CNAME: answer["value"] = v.Target case *dns.NS: answer["value"] = v.Ns case *dns.SPF: answer["value"] = v.Txt case *dns.TXT: answer["value"] = v.Txt case *dns.PTR: answer["value"] = v.Ptr case *dns.SOA: answer["value"] = fmt.Sprintf("%v %v %v %v %v %v %v", v.Ns, v.Mbox, v.Serial, v.Refresh, v.Retry, v.Expire, v.Minttl) case *dns.CAA: answer["value"] = fmt.Sprintf("%v %v \"%v\"", v.Flag, v.Tag, v.Value) case *dns.HINFO: answer["value"] = fmt.Sprintf("\"%v\" \"%v\"", v.Cpu, v.Os) case *dns.RRSIG: answer["value"] = fmt.Sprintf("%v %v %v %v %v %v %v %v %v", dns.TypeToString[v.TypeCovered], v.Algorithm, v.Labels, v.OrigTtl, v.Expiration, v.Inception, v.KeyTag, v.SignerName, v.Signature) default: // type unknown, marshall it as-is answer["value"] = v } answers = append(answers, answer) } jsonentry["answer"] = answers } data = append(data, jsonentry) } json, err := json.Marshal(data) if err != nil { errortext := fmt.Sprintf("Couldn't marshal data into json: %s", err) log.Println(errortext) http.Error(w, errortext, http.StatusInternalServerError) return } w.Header().Set("Content-Type", "application/json") _, err = w.Write(json) if err != nil { errortext := fmt.Sprintf("Unable to write response json: %s", err) log.Println(errortext) http.Error(w, errortext, 500) } } func startQueryLogServer() { listenAddr := "127.0.0.1:8618" // sha512sum of "querylog" then each byte summed http.HandleFunc("/querylog", handler) if err := http.ListenAndServe(listenAddr, nil); err != nil { log.Fatalf("error in ListenAndServe: %s", err) } } func trace(text string) { pc := make([]uintptr, 10) // at least 1 entry needed runtime.Callers(2, pc) f := runtime.FuncForPC(pc[0]) log.Printf("%s(): %s\n", f.Name(), text) }