// SPDX-License-Identifier: BSD-3-Clause package query import ( "errors" "fmt" "strconv" "strings" "time" "git.froth.zone/sam/awl/util" "github.com/miekg/dns" "golang.org/x/net/idna" ) // Message is for overall DNS responses. // //nolint:govet // Better output is worth 32 bytes. type Message struct { Header dns.MsgHdr `json:"header,omitempty" xml:"header,omitempty" yaml:",omitempty"` Opt []Opts `json:"opt,omitempty" xml:"opt,omitempty" yaml:"opt,omitempty"` Question []Question `json:"question,omitempty" xml:"question,omitempty" yaml:",omitempty"` Answer []Answer `json:"answer,omitempty" xml:"answer,omitempty" yaml:",omitempty"` Ns []Answer `json:"ns,omitempty" xml:"ns,omitempty" yaml:",omitempty"` Additional []Answer `json:"additional,omitempty" xml:"additional,omitempty" yaml:",omitempty"` } // Question is a DNS Query. type Question struct { Name string `json:"name,omitempty" xml:"name,omitempty" yaml:",omitempty"` Class string `json:"class,omitempty" xml:"class,omitempty" yaml:",omitempty"` Type string `json:"type,omitempty" xml:"type,omitempty" yaml:",omitempty"` } // RRHeader is for DNS Resource Headers. type RRHeader struct { Name string `json:"name,omitempty" xml:"name,omitempty" yaml:",omitempty"` TTL string `json:"ttl,omitempty" xml:"ttl,omitempty" yaml:",omitempty"` Class string `json:"class,omitempty" xml:"class,omitempty" yaml:",omitempty"` Type string `json:"type,omitempty" xml:"type,omitempty" yaml:",omitempty"` Rdlength uint16 `json:"-" xml:"-" yaml:"-"` } // Opts is for the OPT pseudosection, nearly exclusively for EDNS. type Opts struct { Name string `json:"name,omitempty" xml:"name,omitempty" yaml:",omitempty"` Value string `json:"value" xml:"value" yaml:""` } // Answer is for a DNS Response. type Answer struct { Value string `json:"response,omitempty" xml:"response,omitempty" yaml:"response,omitempty"` RRHeader `json:"header,omitempty" xml:"header,omitempty" yaml:"header,omitempty"` } // ToString turns the response into something that looks a lot like dig // // Much of this is taken from https://github.com/miekg/dns/blob/master/msg.go#L900 func ToString(res util.Response, opts util.Options) (string, error) { if res.DNS == nil { return " MsgHdr", errNoMessage } var ( s string opt *dns.OPT ) if !opts.Short { if opts.Display.Comments { s += res.DNS.MsgHdr.String() + " " s += "QUERY: " + strconv.Itoa(len(res.DNS.Question)) + ", " s += "ANSWER: " + strconv.Itoa(len(res.DNS.Answer)) + ", " s += "AUTHORITY: " + strconv.Itoa(len(res.DNS.Ns)) + ", " s += "ADDITIONAL: " + strconv.Itoa(len(res.DNS.Extra)) + "\n" opt = res.DNS.IsEdns0() if opt != nil && opts.Display.Opt { // OPT PSEUDOSECTION s += opt.String() + "\n" } } if opts.Display.Question { if len(res.DNS.Question) > 0 { if opts.Display.Comments { s += "\n;; QUESTION SECTION:\n" } for _, r := range res.DNS.Question { str, err := stringParse(r.String(), false, opts) if err != nil { return "", fmt.Errorf("%w", err) } s += str + "\n" } } } if opts.Display.Answer { if len(res.DNS.Answer) > 0 { if opts.Display.Comments { s += "\n;; ANSWER SECTION:\n" } for _, r := range res.DNS.Answer { if r != nil { str, err := stringParse(r.String(), true, opts) if err != nil { return "", fmt.Errorf("%w", err) } s += str + "\n" } } } } if opts.Display.Authority { if len(res.DNS.Ns) > 0 { if opts.Display.Comments { s += "\n;; AUTHORITY SECTION:\n" } for _, r := range res.DNS.Ns { if r != nil { str, err := stringParse(r.String(), true, opts) if err != nil { return "", fmt.Errorf("%w", err) } s += str + "\n" } } } } if opts.Display.Additional { if len(res.DNS.Extra) > 0 && (opt == nil || len(res.DNS.Extra) > 1) { if opts.Display.Comments { s += "\n;; ADDITIONAL SECTION:\n" } for _, r := range res.DNS.Extra { if r != nil && r.Header().Rrtype != dns.TypeOPT { str, err := stringParse(r.String(), true, opts) if err != nil { return "", fmt.Errorf("%w", err) } s += str + "\n" } } } } if opts.Display.Statistics { s += "\n;; Query time: " + res.RTT.String() // Add extra information to server string var extra string switch { case opts.TCP: extra = ":" + strconv.Itoa(opts.Port) + " (TCP)" case opts.TLS: extra = ":" + strconv.Itoa(opts.Port) + " (TLS)" case opts.HTTPS, opts.DNSCrypt: extra = "" case opts.QUIC: extra = ":" + strconv.Itoa(opts.Port) + " (QUIC)" default: extra = ":" + strconv.Itoa(opts.Port) + " (UDP)" } s += "\n;; SERVER: " + opts.Request.Server + extra s += "\n;; WHEN: " + time.Now().Format(time.RFC1123Z) s += "\n;; MSG SIZE rcvd: " + strconv.Itoa(res.DNS.Len()) + "\n" } } else { // Print just the responses, nothing else for i, resp := range res.DNS.Answer { temp := strings.Split(resp.String(), "\t") s += temp[len(temp)-1] if opts.Identify { s += " from server " + opts.Request.Server + " in " + res.RTT.String() } // Don't print newline on last line if i != len(res.DNS.Answer)-1 { s += "\n" } } } return s, nil } func stringParse(str string, isAns bool, opts util.Options) (string, error) { split := strings.Split(str, "\t") // Make edits if so requested // TODO: make less ew? // This exists because the question section should be left alone EXCEPT for punycode. if isAns { if !opts.ShowTTL { // Remove from existence split = append(split[:1], split[2:]...) } if !opts.ShowClass { // Position depends on if the TTL is there or not. if opts.ShowTTL { split = append(split[:2], split[3:]...) } else { split = append(split[:1], split[2:]...) } } if opts.ShowTTL && opts.HumanTTL { ttl, _ := strconv.Atoi(split[1]) split[1] = (time.Duration(ttl) * time.Second).String() } } if opts.Display.UcodeTranslate { var ( err error semi string ) if strings.HasPrefix(split[0], ";") { split[0] = strings.TrimPrefix(split[0], ";") semi = ";" } split[0], err = idna.ToUnicode(split[0]) if err != nil { return "", fmt.Errorf("punycode: %w", err) } split[0] = semi + split[0] } return strings.Join(split, "\t"), nil } var errNoMessage = errors.New("no message")