mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-26 03:25:35 +00:00
881bb8bcdc
Go 1.17 switches to a register ABI on amd64 platforms. Part of that switch is that go and defer calls use an argument-less closure, which allocates. This means that we have an extra alloc in some DNS work. That's unfortunate but not a showstopper, and I don't see a clear path to fixing it. The other performance benefits from the register ABI will all but certainly outweigh this extra alloc. Fixes #2545 Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
1072 lines
29 KiB
Go
1072 lines
29 KiB
Go
// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package resolver
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import (
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"bytes"
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"encoding/hex"
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"errors"
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"fmt"
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"math/rand"
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"net"
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"runtime"
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"strconv"
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"strings"
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"testing"
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dns "golang.org/x/net/dns/dnsmessage"
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"inet.af/netaddr"
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"tailscale.com/tstest"
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"tailscale.com/util/dnsname"
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"tailscale.com/wgengine/monitor"
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)
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var testipv4 = netaddr.MustParseIP("1.2.3.4")
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var testipv6 = netaddr.MustParseIP("0001:0203:0405:0607:0809:0a0b:0c0d:0e0f")
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var dnsCfg = Config{
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Hosts: map[dnsname.FQDN][]netaddr.IP{
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"test1.ipn.dev.": []netaddr.IP{testipv4},
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"test2.ipn.dev.": []netaddr.IP{testipv6},
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},
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LocalDomains: []dnsname.FQDN{"ipn.dev."},
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}
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const noEdns = 0
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func dnspacket(domain dnsname.FQDN, tp dns.Type, ednsSize uint16) []byte {
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var dnsHeader dns.Header
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question := dns.Question{
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Name: dns.MustNewName(domain.WithTrailingDot()),
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Type: tp,
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Class: dns.ClassINET,
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}
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builder := dns.NewBuilder(nil, dnsHeader)
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if err := builder.StartQuestions(); err != nil {
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panic(err)
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}
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if err := builder.Question(question); err != nil {
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panic(err)
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}
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if ednsSize != noEdns {
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if err := builder.StartAdditionals(); err != nil {
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panic(err)
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}
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ednsHeader := dns.ResourceHeader{
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Name: dns.MustNewName("."),
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Type: dns.TypeOPT,
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Class: dns.Class(ednsSize),
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}
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if err := builder.OPTResource(ednsHeader, dns.OPTResource{}); err != nil {
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panic(err)
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}
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}
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payload, _ := builder.Finish()
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return payload
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}
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type dnsResponse struct {
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ip netaddr.IP
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txt []string
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name dnsname.FQDN
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rcode dns.RCode
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truncated bool
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requestEdns bool
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requestEdnsSize uint16
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responseEdns bool
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responseEdnsSize uint16
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}
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func unpackResponse(payload []byte) (dnsResponse, error) {
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var response dnsResponse
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var parser dns.Parser
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h, err := parser.Start(payload)
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if err != nil {
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return response, err
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}
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if !h.Response {
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return response, errors.New("not a response")
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}
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response.rcode = h.RCode
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if response.rcode != dns.RCodeSuccess {
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return response, nil
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}
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response.truncated = h.Truncated
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if response.truncated {
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// TODO(#2067): Ideally, answer processing should still succeed when
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// dealing with a truncated message, but currently when we truncate
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// a packet, it's caused by the buffer being too small and usually that
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// means the data runs out mid-record. dns.Parser does not like it when
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// that happens. We can improve this by trimming off incomplete records.
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return response, nil
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}
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err = parser.SkipAllQuestions()
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if err != nil {
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return response, err
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}
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for {
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ah, err := parser.AnswerHeader()
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if err == dns.ErrSectionDone {
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break
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}
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if err != nil {
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return response, err
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}
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switch ah.Type {
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case dns.TypeA:
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res, err := parser.AResource()
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if err != nil {
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return response, err
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}
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response.ip = netaddr.IPv4(res.A[0], res.A[1], res.A[2], res.A[3])
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case dns.TypeAAAA:
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res, err := parser.AAAAResource()
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if err != nil {
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return response, err
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}
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response.ip = netaddr.IPv6Raw(res.AAAA)
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case dns.TypeTXT:
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res, err := parser.TXTResource()
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if err != nil {
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return response, err
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}
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response.txt = res.TXT
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case dns.TypeNS:
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res, err := parser.NSResource()
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if err != nil {
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return response, err
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}
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response.name, err = dnsname.ToFQDN(res.NS.String())
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if err != nil {
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return response, err
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}
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default:
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return response, errors.New("type not in {A, AAAA, NS}")
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}
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}
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err = parser.SkipAllAuthorities()
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if err != nil {
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return response, err
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}
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for {
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ah, err := parser.AdditionalHeader()
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if err == dns.ErrSectionDone {
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break
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}
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if err != nil {
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return response, err
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}
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switch ah.Type {
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case dns.TypeOPT:
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_, err := parser.OPTResource()
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if err != nil {
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return response, err
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}
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response.responseEdns = true
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response.responseEdnsSize = uint16(ah.Class)
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case dns.TypeTXT:
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res, err := parser.TXTResource()
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if err != nil {
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return response, err
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}
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switch ah.Name.String() {
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case "query-info.test.":
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for _, msg := range res.TXT {
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s := strings.SplitN(msg, "=", 2)
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if len(s) != 2 {
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continue
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}
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switch s[0] {
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case "EDNS":
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response.requestEdns, err = strconv.ParseBool(s[1])
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if err != nil {
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return response, err
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}
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case "maxSize":
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sz, err := strconv.ParseUint(s[1], 10, 16)
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if err != nil {
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return response, err
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}
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response.requestEdnsSize = uint16(sz)
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}
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}
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}
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}
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}
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return response, nil
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}
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func syncRespond(r *Resolver, query []byte) ([]byte, error) {
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if err := r.EnqueueRequest(query, netaddr.IPPort{}); err != nil {
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return nil, fmt.Errorf("EnqueueRequest: %w", err)
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}
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payload, _, err := r.NextResponse()
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return payload, err
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}
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func mustIP(str string) netaddr.IP {
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ip, err := netaddr.ParseIP(str)
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if err != nil {
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panic(err)
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}
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return ip
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}
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func TestRDNSNameToIPv4(t *testing.T) {
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tests := []struct {
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name string
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input dnsname.FQDN
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wantIP netaddr.IP
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wantOK bool
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}{
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{"valid", "4.123.24.1.in-addr.arpa.", netaddr.IPv4(1, 24, 123, 4), true},
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{"double_dot", "1..2.3.in-addr.arpa.", netaddr.IP{}, false},
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{"overflow", "1.256.3.4.in-addr.arpa.", netaddr.IP{}, false},
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{"not_ip", "sub.do.ma.in.in-addr.arpa.", netaddr.IP{}, false},
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}
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for _, tt := range tests {
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t.Run(tt.name, func(t *testing.T) {
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ip, ok := rdnsNameToIPv4(tt.input)
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if ok != tt.wantOK {
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t.Errorf("ok = %v; want %v", ok, tt.wantOK)
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} else if ok && ip != tt.wantIP {
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t.Errorf("ip = %v; want %v", ip, tt.wantIP)
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}
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})
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}
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}
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func TestRDNSNameToIPv6(t *testing.T) {
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tests := []struct {
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name string
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input dnsname.FQDN
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wantIP netaddr.IP
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wantOK bool
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}{
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{
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"valid",
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"b.a.9.8.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
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mustIP("2001:db8::567:89ab"),
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true,
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},
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{
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"double_dot",
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"b..9.8.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
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netaddr.IP{},
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false,
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},
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{
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"double_hex",
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"b.a.98.0.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
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netaddr.IP{},
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false,
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},
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{
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"not_hex",
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"b.a.g.0.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
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netaddr.IP{},
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false,
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},
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}
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for _, tt := range tests {
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t.Run(tt.name, func(t *testing.T) {
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ip, ok := rdnsNameToIPv6(tt.input)
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if ok != tt.wantOK {
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t.Errorf("ok = %v; want %v", ok, tt.wantOK)
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} else if ok && ip != tt.wantIP {
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t.Errorf("ip = %v; want %v", ip, tt.wantIP)
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}
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})
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}
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}
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func newResolver(t testing.TB) *Resolver {
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return New(t.Logf, nil /* no link monitor */, nil /* no link selector */)
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}
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func TestResolveLocal(t *testing.T) {
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r := newResolver(t)
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defer r.Close()
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r.SetConfig(dnsCfg)
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tests := []struct {
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name string
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qname dnsname.FQDN
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qtype dns.Type
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ip netaddr.IP
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code dns.RCode
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}{
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{"ipv4", "test1.ipn.dev.", dns.TypeA, testipv4, dns.RCodeSuccess},
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{"ipv6", "test2.ipn.dev.", dns.TypeAAAA, testipv6, dns.RCodeSuccess},
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{"no-ipv6", "test1.ipn.dev.", dns.TypeAAAA, netaddr.IP{}, dns.RCodeSuccess},
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{"nxdomain", "test3.ipn.dev.", dns.TypeA, netaddr.IP{}, dns.RCodeNameError},
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{"foreign domain", "google.com.", dns.TypeA, netaddr.IP{}, dns.RCodeRefused},
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{"all", "test1.ipn.dev.", dns.TypeA, testipv4, dns.RCodeSuccess},
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{"mx-ipv4", "test1.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeSuccess},
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{"mx-ipv6", "test2.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeSuccess},
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{"mx-nxdomain", "test3.ipn.dev.", dns.TypeMX, netaddr.IP{}, dns.RCodeNameError},
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{"ns-nxdomain", "test3.ipn.dev.", dns.TypeNS, netaddr.IP{}, dns.RCodeNameError},
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{"onion-domain", "footest.onion.", dns.TypeA, netaddr.IP{}, dns.RCodeNameError},
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}
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for _, tt := range tests {
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t.Run(tt.name, func(t *testing.T) {
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ip, code := r.resolveLocal(tt.qname, tt.qtype)
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if code != tt.code {
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t.Errorf("code = %v; want %v", code, tt.code)
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}
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// Only check ip for non-err
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if ip != tt.ip {
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t.Errorf("ip = %v; want %v", ip, tt.ip)
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}
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})
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}
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}
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func TestResolveLocalReverse(t *testing.T) {
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r := newResolver(t)
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defer r.Close()
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r.SetConfig(dnsCfg)
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tests := []struct {
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name string
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ip netaddr.IP
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want dnsname.FQDN
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code dns.RCode
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}{
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{"ipv4", testipv4, "test1.ipn.dev.", dns.RCodeSuccess},
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{"ipv6", testipv6, "test2.ipn.dev.", dns.RCodeSuccess},
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{"nxdomain", netaddr.IPv4(4, 3, 2, 1), "", dns.RCodeNameError},
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}
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for _, tt := range tests {
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t.Run(tt.name, func(t *testing.T) {
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name, code := r.resolveLocalReverse(tt.ip)
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if code != tt.code {
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t.Errorf("code = %v; want %v", code, tt.code)
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}
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if name != tt.want {
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t.Errorf("ip = %v; want %v", name, tt.want)
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}
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})
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}
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}
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func ipv6Works() bool {
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c, err := net.Listen("tcp", "[::1]:0")
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if err != nil {
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return false
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}
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c.Close()
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return true
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}
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func generateTXT(size int, source rand.Source) []string {
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const sizePerTXT = 120
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if size%2 != 0 {
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panic("even lengths only")
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}
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rng := rand.New(source)
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txts := make([]string, 0, size/sizePerTXT+1)
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raw := make([]byte, sizePerTXT/2)
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rem := size
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for ; rem > sizePerTXT; rem -= sizePerTXT {
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rng.Read(raw)
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txts = append(txts, hex.EncodeToString(raw))
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}
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if rem > 0 {
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rng.Read(raw[:rem/2])
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txts = append(txts, hex.EncodeToString(raw[:rem/2]))
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}
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return txts
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}
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func TestDelegate(t *testing.T) {
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tstest.ResourceCheck(t)
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if !ipv6Works() {
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t.Skip("skipping test that requires localhost IPv6")
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}
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randSource := rand.NewSource(4)
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// smallTXT does not require EDNS
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smallTXT := generateTXT(300, randSource)
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// medTXT and largeTXT are responses that require EDNS but we would like to
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// support these sizes of response without truncation because they are
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// moderately common.
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medTXT := generateTXT(1200, randSource)
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largeTXT := generateTXT(3900, randSource)
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// xlargeTXT is slightly above the maximum response size that we support,
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// so there should be truncation.
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xlargeTXT := generateTXT(5000, randSource)
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// hugeTXT is significantly larger than any typical MTU and will require
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// significant fragmentation. For buffer management reasons, we do not
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// intend to handle responses this large, so there should be truncation.
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hugeTXT := generateTXT(64000, randSource)
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records := []interface{}{
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"test.site.",
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resolveToIP(testipv4, testipv6, "dns.test.site."),
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"nxdomain.site.", resolveToNXDOMAIN,
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"small.txt.", resolveToTXT(smallTXT, noEdns),
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"smalledns.txt.", resolveToTXT(smallTXT, 512),
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"med.txt.", resolveToTXT(medTXT, 1500),
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"large.txt.", resolveToTXT(largeTXT, maxResponseBytes),
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"xlarge.txt.", resolveToTXT(xlargeTXT, 8000),
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"huge.txt.", resolveToTXT(hugeTXT, 65527),
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}
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v4server := serveDNS(t, "127.0.0.1:0", records...)
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defer v4server.Shutdown()
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v6server := serveDNS(t, "[::1]:0", records...)
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defer v6server.Shutdown()
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r := newResolver(t)
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defer r.Close()
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cfg := dnsCfg
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cfg.Routes = map[dnsname.FQDN][]netaddr.IPPort{
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".": {
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netaddr.MustParseIPPort(v4server.PacketConn.LocalAddr().String()),
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netaddr.MustParseIPPort(v6server.PacketConn.LocalAddr().String()),
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},
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}
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r.SetConfig(cfg)
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tests := []struct {
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title string
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query []byte
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response dnsResponse
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}{
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{
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"ipv4",
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dnspacket("test.site.", dns.TypeA, noEdns),
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dnsResponse{ip: testipv4, rcode: dns.RCodeSuccess},
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},
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{
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"ipv6",
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dnspacket("test.site.", dns.TypeAAAA, noEdns),
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dnsResponse{ip: testipv6, rcode: dns.RCodeSuccess},
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},
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{
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"ns",
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dnspacket("test.site.", dns.TypeNS, noEdns),
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dnsResponse{name: "dns.test.site.", rcode: dns.RCodeSuccess},
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},
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{
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"nxdomain",
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dnspacket("nxdomain.site.", dns.TypeA, noEdns),
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dnsResponse{rcode: dns.RCodeNameError},
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},
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{
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"smalltxt",
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dnspacket("small.txt.", dns.TypeTXT, 8000),
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dnsResponse{txt: smallTXT, rcode: dns.RCodeSuccess, requestEdns: true, requestEdnsSize: maxResponseBytes},
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},
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{
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"smalltxtedns",
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dnspacket("smalledns.txt.", dns.TypeTXT, 512),
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dnsResponse{
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txt: smallTXT,
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rcode: dns.RCodeSuccess,
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requestEdns: true,
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requestEdnsSize: 512,
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responseEdns: true,
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responseEdnsSize: 512,
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},
|
|
},
|
|
{
|
|
"medtxt",
|
|
dnspacket("med.txt.", dns.TypeTXT, 2000),
|
|
dnsResponse{
|
|
txt: medTXT,
|
|
rcode: dns.RCodeSuccess,
|
|
requestEdns: true,
|
|
requestEdnsSize: 2000,
|
|
responseEdns: true,
|
|
responseEdnsSize: 1500,
|
|
},
|
|
},
|
|
{
|
|
"largetxt",
|
|
dnspacket("large.txt.", dns.TypeTXT, maxResponseBytes),
|
|
dnsResponse{
|
|
txt: largeTXT,
|
|
rcode: dns.RCodeSuccess,
|
|
requestEdns: true,
|
|
requestEdnsSize: maxResponseBytes,
|
|
responseEdns: true,
|
|
responseEdnsSize: maxResponseBytes,
|
|
},
|
|
},
|
|
{
|
|
"xlargetxt",
|
|
dnspacket("xlarge.txt.", dns.TypeTXT, 8000),
|
|
dnsResponse{
|
|
rcode: dns.RCodeSuccess,
|
|
truncated: true,
|
|
// request/response EDNS fields will be unset because of
|
|
// they were truncated away
|
|
},
|
|
},
|
|
{
|
|
"hugetxt",
|
|
dnspacket("huge.txt.", dns.TypeTXT, 8000),
|
|
dnsResponse{
|
|
rcode: dns.RCodeSuccess,
|
|
truncated: true,
|
|
// request/response EDNS fields will be unset because of
|
|
// they were truncated away
|
|
},
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
t.Run(tt.title, func(t *testing.T) {
|
|
if tt.title == "hugetxt" && runtime.GOOS == "darwin" {
|
|
t.Skip("known to not work on macOS: https://github.com/tailscale/tailscale/issues/2229")
|
|
}
|
|
payload, err := syncRespond(r, tt.query)
|
|
if err != nil {
|
|
t.Errorf("err = %v; want nil", err)
|
|
return
|
|
}
|
|
response, err := unpackResponse(payload)
|
|
if err != nil {
|
|
t.Errorf("extract: err = %v; want nil (in %x)", err, payload)
|
|
return
|
|
}
|
|
if response.rcode != tt.response.rcode {
|
|
t.Errorf("rcode = %v; want %v", response.rcode, tt.response.rcode)
|
|
}
|
|
if response.ip != tt.response.ip {
|
|
t.Errorf("ip = %v; want %v", response.ip, tt.response.ip)
|
|
}
|
|
if response.name != tt.response.name {
|
|
t.Errorf("name = %v; want %v", response.name, tt.response.name)
|
|
}
|
|
if len(response.txt) != len(tt.response.txt) {
|
|
t.Errorf("%v txt records, want %v txt records", len(response.txt), len(tt.response.txt))
|
|
} else {
|
|
for i := range response.txt {
|
|
if response.txt[i] != tt.response.txt[i] {
|
|
t.Errorf("txt record %v is %s, want %s", i, response.txt[i], tt.response.txt[i])
|
|
}
|
|
}
|
|
}
|
|
if response.requestEdns != tt.response.requestEdns {
|
|
t.Errorf("requestEdns = %v; want %v", response.requestEdns, tt.response.requestEdns)
|
|
}
|
|
if response.requestEdnsSize != tt.response.requestEdnsSize {
|
|
t.Errorf("requestEdnsSize = %v; want %v", response.requestEdnsSize, tt.response.requestEdnsSize)
|
|
}
|
|
if response.responseEdns != tt.response.responseEdns {
|
|
t.Errorf("responseEdns = %v; want %v", response.requestEdns, tt.response.requestEdns)
|
|
}
|
|
if response.responseEdnsSize != tt.response.responseEdnsSize {
|
|
t.Errorf("responseEdnsSize = %v; want %v", response.responseEdnsSize, tt.response.responseEdnsSize)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestDelegateSplitRoute(t *testing.T) {
|
|
test4 := netaddr.MustParseIP("2.3.4.5")
|
|
test6 := netaddr.MustParseIP("ff::1")
|
|
|
|
server1 := serveDNS(t, "127.0.0.1:0",
|
|
"test.site.", resolveToIP(testipv4, testipv6, "dns.test.site."))
|
|
defer server1.Shutdown()
|
|
server2 := serveDNS(t, "127.0.0.1:0",
|
|
"test.other.", resolveToIP(test4, test6, "dns.other."))
|
|
defer server2.Shutdown()
|
|
|
|
r := newResolver(t)
|
|
defer r.Close()
|
|
|
|
cfg := dnsCfg
|
|
cfg.Routes = map[dnsname.FQDN][]netaddr.IPPort{
|
|
".": {netaddr.MustParseIPPort(server1.PacketConn.LocalAddr().String())},
|
|
"other.": {netaddr.MustParseIPPort(server2.PacketConn.LocalAddr().String())},
|
|
}
|
|
r.SetConfig(cfg)
|
|
|
|
tests := []struct {
|
|
title string
|
|
query []byte
|
|
response dnsResponse
|
|
}{
|
|
{
|
|
"general",
|
|
dnspacket("test.site.", dns.TypeA, noEdns),
|
|
dnsResponse{ip: testipv4, rcode: dns.RCodeSuccess},
|
|
},
|
|
{
|
|
"override",
|
|
dnspacket("test.other.", dns.TypeA, noEdns),
|
|
dnsResponse{ip: test4, rcode: dns.RCodeSuccess},
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
t.Run(tt.title, func(t *testing.T) {
|
|
payload, err := syncRespond(r, tt.query)
|
|
if err != nil {
|
|
t.Errorf("err = %v; want nil", err)
|
|
return
|
|
}
|
|
response, err := unpackResponse(payload)
|
|
if err != nil {
|
|
t.Errorf("extract: err = %v; want nil (in %x)", err, payload)
|
|
return
|
|
}
|
|
if response.rcode != tt.response.rcode {
|
|
t.Errorf("rcode = %v; want %v", response.rcode, tt.response.rcode)
|
|
}
|
|
if response.ip != tt.response.ip {
|
|
t.Errorf("ip = %v; want %v", response.ip, tt.response.ip)
|
|
}
|
|
if response.name != tt.response.name {
|
|
t.Errorf("name = %v; want %v", response.name, tt.response.name)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestDelegateCollision(t *testing.T) {
|
|
server := serveDNS(t, "127.0.0.1:0",
|
|
"test.site.", resolveToIP(testipv4, testipv6, "dns.test.site."))
|
|
defer server.Shutdown()
|
|
|
|
r := newResolver(t)
|
|
defer r.Close()
|
|
|
|
cfg := dnsCfg
|
|
cfg.Routes = map[dnsname.FQDN][]netaddr.IPPort{
|
|
".": {
|
|
netaddr.MustParseIPPort(server.PacketConn.LocalAddr().String()),
|
|
},
|
|
}
|
|
r.SetConfig(cfg)
|
|
|
|
packets := []struct {
|
|
qname dnsname.FQDN
|
|
qtype dns.Type
|
|
addr netaddr.IPPort
|
|
}{
|
|
{"test.site.", dns.TypeA, netaddr.IPPortFrom(netaddr.IPv4(1, 1, 1, 1), 1001)},
|
|
{"test.site.", dns.TypeAAAA, netaddr.IPPortFrom(netaddr.IPv4(1, 1, 1, 1), 1002)},
|
|
}
|
|
|
|
// packets will have the same dns txid.
|
|
for _, p := range packets {
|
|
payload := dnspacket(p.qname, p.qtype, noEdns)
|
|
err := r.EnqueueRequest(payload, p.addr)
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
}
|
|
|
|
// Despite the txid collision, the answer(s) should still match the query.
|
|
resp, addr, err := r.NextResponse()
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
|
|
var p dns.Parser
|
|
_, err = p.Start(resp)
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
err = p.SkipAllQuestions()
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
ans, err := p.AllAnswers()
|
|
if err != nil {
|
|
t.Error(err)
|
|
}
|
|
|
|
var wantType dns.Type
|
|
switch ans[0].Body.(type) {
|
|
case *dns.AResource:
|
|
wantType = dns.TypeA
|
|
case *dns.AAAAResource:
|
|
wantType = dns.TypeAAAA
|
|
default:
|
|
t.Errorf("unexpected answer type: %T", ans[0].Body)
|
|
}
|
|
|
|
for _, p := range packets {
|
|
if p.qtype == wantType && p.addr != addr {
|
|
t.Errorf("addr = %v; want %v", addr, p.addr)
|
|
}
|
|
}
|
|
}
|
|
|
|
var allResponse = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0xff, 0x00, 0x01, // type ALL, class IN
|
|
// Answer:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x04, // length: 4 bytes
|
|
0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4
|
|
}
|
|
|
|
var ipv4Response = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
// Answer:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x04, // length: 4 bytes
|
|
0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4
|
|
}
|
|
|
|
var ipv6Response = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN
|
|
// Answer:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x10, // length: 16 bytes
|
|
// AAAA: 0001:0203:0405:0607:0809:0A0B:0C0D:0E0F
|
|
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0xb, 0xc, 0xd, 0xe, 0xf,
|
|
}
|
|
|
|
var ipv4UppercaseResponse = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x54, 0x45, 0x53, 0x54, 0x31, 0x03, 0x49, 0x50, 0x4e, 0x03, 0x44, 0x45, 0x56, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
// Answer:
|
|
0x05, 0x54, 0x45, 0x53, 0x54, 0x31, 0x03, 0x49, 0x50, 0x4e, 0x03, 0x44, 0x45, 0x56, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x04, // length: 4 bytes
|
|
0x01, 0x02, 0x03, 0x04, // A: 1.2.3.4
|
|
}
|
|
|
|
var ptrResponse = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question: 4.3.2.1.in-addr.arpa
|
|
0x01, 0x34, 0x01, 0x33, 0x01, 0x32, 0x01, 0x31, 0x07,
|
|
0x69, 0x6e, 0x2d, 0x61, 0x64, 0x64, 0x72, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00,
|
|
0x00, 0x0c, 0x00, 0x01, // type PTR, class IN
|
|
// Answer: 4.3.2.1.in-addr.arpa
|
|
0x01, 0x34, 0x01, 0x33, 0x01, 0x32, 0x01, 0x31, 0x07,
|
|
0x69, 0x6e, 0x2d, 0x61, 0x64, 0x64, 0x72, 0x04, 0x61, 0x72, 0x70, 0x61, 0x00,
|
|
0x00, 0x0c, 0x00, 0x01, // type PTR, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x0f, // length: 15 bytes
|
|
// PTR: test1.ipn.dev
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00,
|
|
}
|
|
|
|
var ptrResponse6 = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x01, // one answer
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question: f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa
|
|
0x01, 0x66, 0x01, 0x30, 0x01, 0x65, 0x01, 0x30,
|
|
0x01, 0x64, 0x01, 0x30, 0x01, 0x63, 0x01, 0x30,
|
|
0x01, 0x62, 0x01, 0x30, 0x01, 0x61, 0x01, 0x30,
|
|
0x01, 0x39, 0x01, 0x30, 0x01, 0x38, 0x01, 0x30,
|
|
0x01, 0x37, 0x01, 0x30, 0x01, 0x36, 0x01, 0x30,
|
|
0x01, 0x35, 0x01, 0x30, 0x01, 0x34, 0x01, 0x30,
|
|
0x01, 0x33, 0x01, 0x30, 0x01, 0x32, 0x01, 0x30,
|
|
0x01, 0x31, 0x01, 0x30, 0x01, 0x30, 0x01, 0x30,
|
|
0x03, 0x69, 0x70, 0x36,
|
|
0x04, 0x61, 0x72, 0x70, 0x61, 0x00,
|
|
0x00, 0x0c, 0x00, 0x01, // type PTR, class IN6
|
|
// Answer: f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa
|
|
0x01, 0x66, 0x01, 0x30, 0x01, 0x65, 0x01, 0x30,
|
|
0x01, 0x64, 0x01, 0x30, 0x01, 0x63, 0x01, 0x30,
|
|
0x01, 0x62, 0x01, 0x30, 0x01, 0x61, 0x01, 0x30,
|
|
0x01, 0x39, 0x01, 0x30, 0x01, 0x38, 0x01, 0x30,
|
|
0x01, 0x37, 0x01, 0x30, 0x01, 0x36, 0x01, 0x30,
|
|
0x01, 0x35, 0x01, 0x30, 0x01, 0x34, 0x01, 0x30,
|
|
0x01, 0x33, 0x01, 0x30, 0x01, 0x32, 0x01, 0x30,
|
|
0x01, 0x31, 0x01, 0x30, 0x01, 0x30, 0x01, 0x30,
|
|
0x03, 0x69, 0x70, 0x36,
|
|
0x04, 0x61, 0x72, 0x70, 0x61, 0x00,
|
|
0x00, 0x0c, 0x00, 0x01, // type PTR, class IN
|
|
0x00, 0x00, 0x02, 0x58, // TTL: 600
|
|
0x00, 0x0f, // length: 15 bytes
|
|
// PTR: test2.ipn.dev
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x32, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00,
|
|
}
|
|
|
|
var nxdomainResponse = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x03, // flags: response, authoritative, error: nxdomain
|
|
0x00, 0x01, // one question
|
|
0x00, 0x00, // no answers
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x33, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x01, 0x00, 0x01, // type A, class IN
|
|
}
|
|
|
|
var emptyResponse = []byte{
|
|
0x00, 0x00, // transaction id: 0
|
|
0x84, 0x00, // flags: response, authoritative, no error
|
|
0x00, 0x01, // one question
|
|
0x00, 0x00, // no answers
|
|
0x00, 0x00, 0x00, 0x00, // no authority or additional RRs
|
|
// Question:
|
|
0x05, 0x74, 0x65, 0x73, 0x74, 0x31, 0x03, 0x69, 0x70, 0x6e, 0x03, 0x64, 0x65, 0x76, 0x00, // name
|
|
0x00, 0x1c, 0x00, 0x01, // type AAAA, class IN
|
|
}
|
|
|
|
func TestFull(t *testing.T) {
|
|
r := newResolver(t)
|
|
defer r.Close()
|
|
|
|
r.SetConfig(dnsCfg)
|
|
|
|
// One full packet and one error packet
|
|
tests := []struct {
|
|
name string
|
|
request []byte
|
|
response []byte
|
|
}{
|
|
{"all", dnspacket("test1.ipn.dev.", dns.TypeALL, noEdns), allResponse},
|
|
{"ipv4", dnspacket("test1.ipn.dev.", dns.TypeA, noEdns), ipv4Response},
|
|
{"ipv6", dnspacket("test2.ipn.dev.", dns.TypeAAAA, noEdns), ipv6Response},
|
|
{"no-ipv6", dnspacket("test1.ipn.dev.", dns.TypeAAAA, noEdns), emptyResponse},
|
|
{"upper", dnspacket("TEST1.IPN.DEV.", dns.TypeA, noEdns), ipv4UppercaseResponse},
|
|
{"ptr4", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR, noEdns), ptrResponse},
|
|
{"ptr6", dnspacket("f.0.e.0.d.0.c.0.b.0.a.0.9.0.8.0.7.0.6.0.5.0.4.0.3.0.2.0.1.0.0.0.ip6.arpa.",
|
|
dns.TypePTR, noEdns), ptrResponse6},
|
|
{"nxdomain", dnspacket("test3.ipn.dev.", dns.TypeA, noEdns), nxdomainResponse},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
t.Run(tt.name, func(t *testing.T) {
|
|
response, err := syncRespond(r, tt.request)
|
|
if err != nil {
|
|
t.Errorf("err = %v; want nil", err)
|
|
}
|
|
if !bytes.Equal(response, tt.response) {
|
|
t.Errorf("response = %x; want %x", response, tt.response)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestAllocs(t *testing.T) {
|
|
r := newResolver(t)
|
|
defer r.Close()
|
|
r.SetConfig(dnsCfg)
|
|
|
|
// It is seemingly pointless to test allocs in the delegate path,
|
|
// as dialer.Dial -> Read -> Write alone comprise 12 allocs.
|
|
tests := []struct {
|
|
name string
|
|
query []byte
|
|
want int
|
|
}{
|
|
// Name lowercasing, response slice created by dns.NewBuilder,
|
|
// and closure allocation from go call.
|
|
// (Closure allocation only happens when using new register ABI,
|
|
// which is amd64 with Go 1.17, and probably more platforms later.)
|
|
{"forward", dnspacket("test1.ipn.dev.", dns.TypeA, noEdns), 3},
|
|
// 3 extra allocs in rdnsNameToIPv4 and one in marshalPTRRecord (dns.NewName).
|
|
{"reverse", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR, noEdns), 5},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
allocs := testing.AllocsPerRun(100, func() {
|
|
syncRespond(r, tt.query)
|
|
})
|
|
if int(allocs) > tt.want {
|
|
t.Errorf("%s: allocs = %v; want %v", tt.name, allocs, tt.want)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestTrimRDNSBonjourPrefix(t *testing.T) {
|
|
tests := []struct {
|
|
in dnsname.FQDN
|
|
want bool
|
|
}{
|
|
{"b._dns-sd._udp.0.10.20.172.in-addr.arpa.", true},
|
|
{"db._dns-sd._udp.0.10.20.172.in-addr.arpa.", true},
|
|
{"r._dns-sd._udp.0.10.20.172.in-addr.arpa.", true},
|
|
{"dr._dns-sd._udp.0.10.20.172.in-addr.arpa.", true},
|
|
{"lb._dns-sd._udp.0.10.20.172.in-addr.arpa.", true},
|
|
{"qq._dns-sd._udp.0.10.20.172.in-addr.arpa.", false},
|
|
{"0.10.20.172.in-addr.arpa.", false},
|
|
}
|
|
|
|
for _, test := range tests {
|
|
got := hasRDNSBonjourPrefix(test.in)
|
|
if got != test.want {
|
|
t.Errorf("trimRDNSBonjourPrefix(%q) = %v, want %v", test.in, got, test.want)
|
|
}
|
|
}
|
|
}
|
|
|
|
func BenchmarkFull(b *testing.B) {
|
|
server := serveDNS(b, "127.0.0.1:0",
|
|
"test.site.", resolveToIP(testipv4, testipv6, "dns.test.site."))
|
|
defer server.Shutdown()
|
|
|
|
r := newResolver(b)
|
|
defer r.Close()
|
|
|
|
cfg := dnsCfg
|
|
cfg.Routes = map[dnsname.FQDN][]netaddr.IPPort{
|
|
".": {
|
|
netaddr.MustParseIPPort(server.PacketConn.LocalAddr().String()),
|
|
},
|
|
}
|
|
|
|
tests := []struct {
|
|
name string
|
|
request []byte
|
|
}{
|
|
{"forward", dnspacket("test1.ipn.dev.", dns.TypeA, noEdns)},
|
|
{"reverse", dnspacket("4.3.2.1.in-addr.arpa.", dns.TypePTR, noEdns)},
|
|
{"delegated", dnspacket("test.site.", dns.TypeA, noEdns)},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
b.Run(tt.name, func(b *testing.B) {
|
|
for i := 0; i < b.N; i++ {
|
|
syncRespond(r, tt.request)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func TestMarshalResponseFormatError(t *testing.T) {
|
|
resp := new(response)
|
|
resp.Header.RCode = dns.RCodeFormatError
|
|
v, err := marshalResponse(resp)
|
|
if err != nil {
|
|
t.Errorf("marshal error: %v", err)
|
|
}
|
|
t.Logf("response: %q", v)
|
|
}
|
|
|
|
func TestForwardLinkSelection(t *testing.T) {
|
|
old := initListenConfig
|
|
defer func() { initListenConfig = old }()
|
|
|
|
configCall := make(chan string, 1)
|
|
initListenConfig = func(nc *net.ListenConfig, mon *monitor.Mon, tunName string) error {
|
|
select {
|
|
case configCall <- tunName:
|
|
return nil
|
|
default:
|
|
t.Error("buffer full")
|
|
return errors.New("buffer full")
|
|
}
|
|
}
|
|
|
|
// specialIP is some IP we pretend that our link selector
|
|
// routes differently.
|
|
specialIP := netaddr.IPv4(1, 2, 3, 4)
|
|
|
|
fwd := newForwarder(t.Logf, nil, nil, linkSelFunc(func(ip netaddr.IP) string {
|
|
if ip == netaddr.IPv4(1, 2, 3, 4) {
|
|
return "special"
|
|
}
|
|
return ""
|
|
}))
|
|
|
|
// Test non-special IP.
|
|
if got, err := fwd.packetListener(netaddr.IP{}); err != nil {
|
|
t.Fatal(err)
|
|
} else if got != stdNetPacketListener {
|
|
t.Errorf("for IP zero value, didn't get expected packet listener")
|
|
}
|
|
select {
|
|
case v := <-configCall:
|
|
t.Errorf("unexpected ListenConfig call, with tunName %q", v)
|
|
default:
|
|
}
|
|
|
|
// Test that our special IP generates a call to initListenConfig.
|
|
if got, err := fwd.packetListener(specialIP); err != nil {
|
|
t.Fatal(err)
|
|
} else if got == stdNetPacketListener {
|
|
t.Errorf("special IP returned std packet listener; expected unique one")
|
|
}
|
|
if v, ok := <-configCall; !ok {
|
|
t.Errorf("didn't get ListenConfig call")
|
|
} else if v != "special" {
|
|
t.Errorf("got tunName %q; want 'special'", v)
|
|
}
|
|
}
|
|
|
|
type linkSelFunc func(ip netaddr.IP) string
|
|
|
|
func (f linkSelFunc) PickLink(ip netaddr.IP) string { return f(ip) }
|