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|
package dns
import (
"crypto/tls"
"fmt"
"net"
"strconv"
"testing"
"time"
)
func TestClientSync(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
s, addrstr, err := RunLocalUDPServer("127.0.0.1:0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeSOA)
c := new(Client)
r, _, err := c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
if r != nil && r.Rcode != RcodeSuccess {
t.Errorf("failed to get an valid answer\n%v", r)
}
// And now with plain Exchange().
r, err = Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
if r == nil || r.Rcode != RcodeSuccess {
t.Errorf("failed to get an valid answer\n%v", r)
}
}
func TestClientTLSSync(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
cert, err := tls.X509KeyPair(CertPEMBlock, KeyPEMBlock)
if err != nil {
t.Fatalf("unable to build certificate: %v", err)
}
config := tls.Config{
Certificates: []tls.Certificate{cert},
}
s, addrstr, err := RunLocalTLSServer("127.0.0.1:0", &config)
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeSOA)
c := new(Client)
c.Net = "tcp-tls"
c.TLSConfig = &tls.Config{
InsecureSkipVerify: true,
}
r, _, err := c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
if r != nil && r.Rcode != RcodeSuccess {
t.Errorf("failed to get an valid answer\n%v", r)
}
}
func TestClientSyncBadId(t *testing.T) {
HandleFunc("miek.nl.", HelloServerBadId)
defer HandleRemove("miek.nl.")
s, addrstr, err := RunLocalUDPServer("127.0.0.1:0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeSOA)
c := new(Client)
if _, _, err := c.Exchange(m, addrstr); err != ErrId {
t.Errorf("did not find a bad Id")
}
// And now with plain Exchange().
if _, err := Exchange(m, addrstr); err != ErrId {
t.Errorf("did not find a bad Id")
}
}
func TestClientEDNS0(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
s, addrstr, err := RunLocalUDPServer("127.0.0.1:0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeDNSKEY)
m.SetEdns0(2048, true)
c := new(Client)
r, _, err := c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
if r != nil && r.Rcode != RcodeSuccess {
t.Errorf("failed to get an valid answer\n%v", r)
}
}
// Validates the transmission and parsing of local EDNS0 options.
func TestClientEDNS0Local(t *testing.T) {
optStr1 := "1979:0x0707"
optStr2 := strconv.Itoa(EDNS0LOCALSTART) + ":0x0601"
handler := func(w ResponseWriter, req *Msg) {
m := new(Msg)
m.SetReply(req)
m.Extra = make([]RR, 1, 2)
m.Extra[0] = &TXT{Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeTXT, Class: ClassINET, Ttl: 0}, Txt: []string{"Hello local edns"}}
// If the local options are what we expect, then reflect them back.
ec1 := req.Extra[0].(*OPT).Option[0].(*EDNS0_LOCAL).String()
ec2 := req.Extra[0].(*OPT).Option[1].(*EDNS0_LOCAL).String()
if ec1 == optStr1 && ec2 == optStr2 {
m.Extra = append(m.Extra, req.Extra[0])
}
w.WriteMsg(m)
}
HandleFunc("miek.nl.", handler)
defer HandleRemove("miek.nl.")
s, addrstr, err := RunLocalUDPServer("127.0.0.1:0")
if err != nil {
t.Fatalf("unable to run test server: %s", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
// Add two local edns options to the query.
ec1 := &EDNS0_LOCAL{Code: 1979, Data: []byte{7, 7}}
ec2 := &EDNS0_LOCAL{Code: EDNS0LOCALSTART, Data: []byte{6, 1}}
o := &OPT{Hdr: RR_Header{Name: ".", Rrtype: TypeOPT}, Option: []EDNS0{ec1, ec2}}
m.Extra = append(m.Extra, o)
c := new(Client)
r, _, err := c.Exchange(m, addrstr)
if err != nil {
t.Errorf("failed to exchange: %s", err)
}
if r != nil && r.Rcode != RcodeSuccess {
t.Error("failed to get a valid answer")
t.Logf("%v\n", r)
}
txt := r.Extra[0].(*TXT).Txt[0]
if txt != "Hello local edns" {
t.Error("Unexpected result for miek.nl", txt, "!= Hello local edns")
}
// Validate the local options in the reply.
got := r.Extra[1].(*OPT).Option[0].(*EDNS0_LOCAL).String()
if got != optStr1 {
t.Errorf("failed to get local edns0 answer; got %s, expected %s", got, optStr1)
t.Logf("%v\n", r)
}
got = r.Extra[1].(*OPT).Option[1].(*EDNS0_LOCAL).String()
if got != optStr2 {
t.Errorf("failed to get local edns0 answer; got %s, expected %s", got, optStr2)
t.Logf("%v\n", r)
}
}
// ExampleTsigSecret_updateLeaseTSIG shows how to update a lease signed with TSIG
func ExampleTsigSecret_updateLeaseTSIG() {
m := new(Msg)
m.SetUpdate("t.local.ip6.io.")
rr, _ := NewRR("t.local.ip6.io. 30 A 127.0.0.1")
rrs := make([]RR, 1)
rrs[0] = rr
m.Insert(rrs)
leaseRr := new(OPT)
leaseRr.Hdr.Name = "."
leaseRr.Hdr.Rrtype = TypeOPT
e := new(EDNS0_UL)
e.Code = EDNS0UL
e.Lease = 120
leaseRr.Option = append(leaseRr.Option, e)
m.Extra = append(m.Extra, leaseRr)
c := new(Client)
m.SetTsig("polvi.", HmacMD5, 300, time.Now().Unix())
c.TsigSecret = map[string]string{"polvi.": "pRZgBrBvI4NAHZYhxmhs/Q=="}
_, _, err := c.Exchange(m, "127.0.0.1:53")
if err != nil {
panic(err)
}
}
func TestClientConn(t *testing.T) {
HandleFunc("miek.nl.", HelloServer)
defer HandleRemove("miek.nl.")
// This uses TCP just to make it slightly different than TestClientSync
s, addrstr, err := RunLocalTCPServer("127.0.0.1:0")
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer s.Shutdown()
m := new(Msg)
m.SetQuestion("miek.nl.", TypeSOA)
cn, err := Dial("tcp", addrstr)
if err != nil {
t.Errorf("failed to dial %s: %v", addrstr, err)
}
err = cn.WriteMsg(m)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
r, err := cn.ReadMsg()
if r == nil || r.Rcode != RcodeSuccess {
t.Errorf("failed to get an valid answer\n%v", r)
}
err = cn.WriteMsg(m)
if err != nil {
t.Errorf("failed to exchange: %v", err)
}
h := new(Header)
buf, err := cn.ReadMsgHeader(h)
if buf == nil {
t.Errorf("failed to get an valid answer\n%v", r)
}
if int(h.Bits&0xF) != RcodeSuccess {
t.Errorf("failed to get an valid answer in ReadMsgHeader\n%v", r)
}
if h.Ancount != 0 || h.Qdcount != 1 || h.Nscount != 0 || h.Arcount != 1 {
t.Errorf("expected to have question and additional in response; got something else: %+v", h)
}
if err = r.Unpack(buf); err != nil {
t.Errorf("unable to unpack message fully: %v", err)
}
}
func TestTruncatedMsg(t *testing.T) {
m := new(Msg)
m.SetQuestion("miek.nl.", TypeSRV)
cnt := 10
for i := 0; i < cnt; i++ {
r := &SRV{
Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeSRV, Class: ClassINET, Ttl: 0},
Port: uint16(i + 8000),
Target: "target.miek.nl.",
}
m.Answer = append(m.Answer, r)
re := &A{
Hdr: RR_Header{Name: m.Question[0].Name, Rrtype: TypeA, Class: ClassINET, Ttl: 0},
A: net.ParseIP(fmt.Sprintf("127.0.0.%d", i)).To4(),
}
m.Extra = append(m.Extra, re)
}
buf, err := m.Pack()
if err != nil {
t.Errorf("failed to pack: %v", err)
}
r := new(Msg)
if err = r.Unpack(buf); err != nil {
t.Errorf("unable to unpack message: %v", err)
}
if len(r.Answer) != cnt {
t.Errorf("answer count after regular unpack doesn't match: %d", len(r.Answer))
}
if len(r.Extra) != cnt {
t.Errorf("extra count after regular unpack doesn't match: %d", len(r.Extra))
}
m.Truncated = true
buf, err = m.Pack()
if err != nil {
t.Errorf("failed to pack truncated: %v", err)
}
r = new(Msg)
if err = r.Unpack(buf); err != nil && err != ErrTruncated {
t.Errorf("unable to unpack truncated message: %v", err)
}
if !r.Truncated {
t.Errorf("truncated message wasn't unpacked as truncated")
}
if len(r.Answer) != cnt {
t.Errorf("answer count after truncated unpack doesn't match: %d", len(r.Answer))
}
if len(r.Extra) != cnt {
t.Errorf("extra count after truncated unpack doesn't match: %d", len(r.Extra))
}
// Now we want to remove almost all of the extra records
// We're going to loop over the extra to get the count of the size of all
// of them
off := 0
buf1 := make([]byte, m.Len())
for i := 0; i < len(m.Extra); i++ {
off, err = PackRR(m.Extra[i], buf1, off, nil, m.Compress)
if err != nil {
t.Errorf("failed to pack extra: %v", err)
}
}
// Remove all of the extra bytes but 10 bytes from the end of buf
off -= 10
buf1 = buf[:len(buf)-off]
r = new(Msg)
if err = r.Unpack(buf1); err != nil && err != ErrTruncated {
t.Errorf("unable to unpack cutoff message: %v", err)
}
if !r.Truncated {
t.Error("truncated cutoff message wasn't unpacked as truncated")
}
if len(r.Answer) != cnt {
t.Errorf("answer count after cutoff unpack doesn't match: %d", len(r.Answer))
}
if len(r.Extra) != 0 {
t.Errorf("extra count after cutoff unpack is not zero: %d", len(r.Extra))
}
// Now we want to remove almost all of the answer records too
buf1 = make([]byte, m.Len())
as := 0
for i := 0; i < len(m.Extra); i++ {
off1 := off
off, err = PackRR(m.Extra[i], buf1, off, nil, m.Compress)
as = off - off1
if err != nil {
t.Errorf("failed to pack extra: %v", err)
}
}
// Keep exactly one answer left
// This should still cause Answer to be nil
off -= as
buf1 = buf[:len(buf)-off]
r = new(Msg)
if err = r.Unpack(buf1); err != nil && err != ErrTruncated {
t.Errorf("unable to unpack cutoff message: %v", err)
}
if !r.Truncated {
t.Error("truncated cutoff message wasn't unpacked as truncated")
}
if len(r.Answer) != 0 {
t.Errorf("answer count after second cutoff unpack is not zero: %d", len(r.Answer))
}
// Now leave only 1 byte of the question
// Since the header is always 12 bytes, we just need to keep 13
buf1 = buf[:13]
r = new(Msg)
err = r.Unpack(buf1)
if err == nil || err == ErrTruncated {
t.Errorf("error should not be ErrTruncated from question cutoff unpack: %v", err)
}
// Finally, if we only have the header, we should still return an error
buf1 = buf[:12]
r = new(Msg)
if err = r.Unpack(buf1); err == nil || err != ErrTruncated {
t.Errorf("error not ErrTruncated from header-only unpack: %v", err)
}
}
func TestTimeout(t *testing.T) {
// Set up a dummy UDP server that won't respond
addr, err := net.ResolveUDPAddr("udp", "127.0.0.1:0")
if err != nil {
t.Fatalf("unable to resolve local udp address: %v", err)
}
conn, err := net.ListenUDP("udp", addr)
if err != nil {
t.Fatalf("unable to run test server: %v", err)
}
defer conn.Close()
addrstr := conn.LocalAddr().String()
// Message to send
m := new(Msg)
m.SetQuestion("miek.nl.", TypeTXT)
// Use a channel + timeout to ensure we don't get stuck if the
// Client Timeout is not working properly
done := make(chan struct{})
timeout := time.Millisecond
allowable := timeout + (10 * time.Millisecond)
abortAfter := timeout + (100 * time.Millisecond)
start := time.Now()
go func() {
c := &Client{Timeout: timeout}
_, _, err := c.Exchange(m, addrstr)
if err == nil {
t.Error("no timeout using Client")
}
done <- struct{}{}
}()
select {
case <-done:
case <-time.After(abortAfter):
}
length := time.Since(start)
if length > allowable {
t.Errorf("exchange took longer (%v) than specified Timeout (%v)", length, timeout)
}
}
|