348 lines
7.7 KiB
Go
348 lines
7.7 KiB
Go
// SPDX-License-Identifier: BSD-3-Clause
|
|
|
|
package query
|
|
|
|
import (
|
|
"fmt"
|
|
"strconv"
|
|
"strings"
|
|
"time"
|
|
|
|
"git.froth.zone/sam/awl/util"
|
|
"github.com/dchest/uniuri"
|
|
"github.com/miekg/dns"
|
|
"golang.org/x/net/idna"
|
|
)
|
|
|
|
const (
|
|
tcp = "tcp"
|
|
udp = "udp"
|
|
)
|
|
|
|
// 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 "<nil> 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.Request.Port) + " (TCP)"
|
|
case opts.TLS:
|
|
extra = ":" + strconv.Itoa(opts.Request.Port) + " (TLS)"
|
|
case opts.HTTPS, opts.DNSCrypt:
|
|
extra = ""
|
|
case opts.QUIC:
|
|
extra = ":" + strconv.Itoa(opts.Request.Port) + " (QUIC)"
|
|
default:
|
|
extra = ":" + strconv.Itoa(opts.Request.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
|
|
}
|
|
|
|
// stringParse edits the raw responses to user requests.
|
|
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.Display.TTL {
|
|
// Remove from existence
|
|
split = append(split[:1], split[2:]...)
|
|
}
|
|
|
|
if !opts.Display.ShowClass {
|
|
// Position depends on if the TTL is there or not.
|
|
if opts.Display.TTL {
|
|
split = append(split[:2], split[3:]...)
|
|
} else {
|
|
split = append(split[:1], split[2:]...)
|
|
}
|
|
}
|
|
|
|
if opts.Display.TTL && opts.Display.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
|
|
}
|
|
|
|
// CreateQuery creates a DNS query from the options given.
|
|
// It sets query flags and EDNS flags from the respective options.
|
|
func CreateQuery(opts util.Options) (util.Response, error) {
|
|
req := new(dns.Msg)
|
|
req.SetQuestion(opts.Request.Name, opts.Request.Type)
|
|
req.Question[0].Qclass = opts.Request.Class
|
|
|
|
// Set standard flags
|
|
req.MsgHdr.Response = opts.QR
|
|
req.MsgHdr.Authoritative = opts.AA
|
|
req.MsgHdr.Truncated = opts.TC
|
|
req.MsgHdr.RecursionDesired = opts.RD
|
|
req.MsgHdr.RecursionAvailable = opts.RA
|
|
req.MsgHdr.Zero = opts.Z
|
|
req.MsgHdr.AuthenticatedData = opts.AD
|
|
req.MsgHdr.CheckingDisabled = opts.CD
|
|
|
|
// EDNS time :)
|
|
if opts.EDNS.EnableEDNS {
|
|
o := new(dns.OPT)
|
|
o.Hdr.Name = "."
|
|
o.Hdr.Rrtype = dns.TypeOPT
|
|
|
|
o.SetVersion(opts.EDNS.Version)
|
|
|
|
if opts.EDNS.Cookie {
|
|
e := new(dns.EDNS0_COOKIE)
|
|
e.Code = dns.EDNS0COOKIE
|
|
e.Cookie = uniuri.NewLenChars(8, []byte("1234567890abcdef"))
|
|
o.Option = append(o.Option, e)
|
|
|
|
opts.Logger.Info("Setting EDNS cookie to", e.Cookie)
|
|
}
|
|
|
|
if opts.EDNS.Expire {
|
|
o.Option = append(o.Option, new(dns.EDNS0_EXPIRE))
|
|
|
|
opts.Logger.Info("Setting EDNS Expire option")
|
|
}
|
|
|
|
if opts.EDNS.KeepOpen {
|
|
o.Option = append(o.Option, new(dns.EDNS0_TCP_KEEPALIVE))
|
|
|
|
opts.Logger.Info("Setting EDNS TCP Keepalive option")
|
|
}
|
|
|
|
if opts.EDNS.Nsid {
|
|
o.Option = append(o.Option, new(dns.EDNS0_NSID))
|
|
|
|
opts.Logger.Info("Setting EDNS NSID option")
|
|
}
|
|
|
|
if opts.EDNS.Padding {
|
|
o.Option = append(o.Option, new(dns.EDNS0_PADDING))
|
|
|
|
opts.Logger.Info("Setting EDNS padding")
|
|
}
|
|
|
|
o.SetUDPSize(opts.EDNS.BufSize)
|
|
|
|
opts.Logger.Info("EDNS UDP buffer set to", opts.EDNS.BufSize)
|
|
|
|
o.SetZ(opts.EDNS.ZFlag)
|
|
|
|
opts.Logger.Info("EDNS Z flag set to", opts.EDNS.ZFlag)
|
|
|
|
if opts.EDNS.DNSSEC {
|
|
o.SetDo()
|
|
|
|
opts.Logger.Info("EDNS DNSSEC OK set")
|
|
}
|
|
|
|
if opts.EDNS.Subnet.Address != nil {
|
|
o.Option = append(o.Option, &opts.EDNS.Subnet)
|
|
}
|
|
|
|
req.Extra = append(req.Extra, o)
|
|
} else if opts.EDNS.DNSSEC {
|
|
req.SetEdns0(1232, true)
|
|
opts.Logger.Warn("DNSSEC implies EDNS, EDNS enabled")
|
|
opts.Logger.Info("DNSSEC enabled, UDP buffer set to 1232")
|
|
}
|
|
|
|
opts.Logger.Debug(req)
|
|
|
|
if !opts.Short {
|
|
if opts.Display.ShowQuery {
|
|
opts.Logger.Info("Printing constructed query")
|
|
|
|
var (
|
|
str string
|
|
err error
|
|
)
|
|
|
|
if opts.JSON || opts.XML || opts.YAML {
|
|
str, err = PrintSpecial(req, opts)
|
|
if err != nil {
|
|
return util.Response{}, err
|
|
}
|
|
} else {
|
|
temp := opts.Display.Statistics
|
|
opts.Display.Statistics = false
|
|
str, err = ToString(
|
|
util.Response{
|
|
DNS: req,
|
|
RTT: 0,
|
|
}, opts)
|
|
if err != nil {
|
|
return util.Response{}, err
|
|
}
|
|
|
|
opts.Display.Statistics = temp
|
|
str += "\n;; QUERY SIZE: " + strconv.Itoa(req.Len()) + "\n"
|
|
}
|
|
|
|
fmt.Println(str)
|
|
|
|
opts.Display.ShowQuery = false
|
|
}
|
|
}
|
|
|
|
resolver, err := LoadResolver(opts)
|
|
if err != nil {
|
|
return util.Response{}, err
|
|
}
|
|
|
|
opts.Logger.Info("Query successfully loaded")
|
|
|
|
//nolint:wrapcheck // Error wrapping not needed here
|
|
return resolver.LookUp(req)
|
|
}
|