Merge branch 'master' of github.com:miekg/coredns

This commit is contained in:
Miek Gieben
2016-11-29 21:58:13 +00:00
17 changed files with 120 additions and 64 deletions

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@@ -37,7 +37,7 @@ etcd [ZONES...] {
* **ENDPOINT** the etcd endpoints. Defaults to "http://localhost:2397".
* `upstream` upstream resolvers to be used resolve external names found in etcd (think CNAMEs)
pointing to external names. If you want CoreDNS to act as a proxy for clients, you'll need to add
the proxy middleware. **ADDRESS* can be an IP address, and IP:port or a string pointing to a file
the proxy middleware. **ADDRESS** can be an IP address, and IP:port or a string pointing to a file
that is structured as /etc/resolv.conf.
* `tls` followed the cert, key and the CA's cert filenames.
* `debug` allows for debug queries. Prefix the name with `o-o.debug.` to retrieve extra information in the
@@ -127,7 +127,7 @@ Or with *debug* queries enabled:
When debug queries are enabled CoreDNS will return errors and etcd records encountered during the resolution
process in the response. The general form looks like this:
skydns.test.skydns.dom.a. 300 CH TXT "127.0.0.1:0(10,0,,false)[0,]"
skydns.test.skydns.dom.a. 0 CH TXT "127.0.0.1:0(10,0,,false)[0,]"
This shows the complete key as the owername, the rdata of the TXT record has:
`host:port(priority,weight,txt content,mail)[targetstrip,group]`.

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@@ -1,20 +0,0 @@
package etcd
import "strings"
const debugName = "o-o.debug."
// isDebug checks if name is a debugging name, i.e. starts with o-o.debug.
// it return the empty string if it is not a debug message, otherwise it will return the
// name with o-o.debug. stripped off. Must be called with name lowercased.
func isDebug(name string) string {
if len(name) == len(debugName) {
return ""
}
name = strings.ToLower(name)
debug := strings.HasPrefix(name, debugName)
if !debug {
return ""
}
return name[len(debugName):]
}

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@@ -4,7 +4,6 @@ package etcd
import (
"sort"
"strings"
"testing"
"github.com/miekg/coredns/middleware/etcd/msg"
@@ -14,21 +13,6 @@ import (
"github.com/miekg/dns"
)
func TestIsDebug(t *testing.T) {
if ok := isDebug("o-o.debug.miek.nl."); ok != "miek.nl." {
t.Errorf("expected o-o.debug.miek.nl. to be debug")
}
if ok := isDebug(strings.ToLower("o-o.Debug.miek.nl.")); ok != "miek.nl." {
t.Errorf("expected o-o.Debug.miek.nl. to be debug")
}
if ok := isDebug("i-o.debug.miek.nl."); ok != "" {
t.Errorf("expected i-o.Debug.miek.nl. to be non-debug")
}
if ok := isDebug(strings.ToLower("i-o.Debug.")); ok != "" {
t.Errorf("expected o-o.Debug. to be non-debug")
}
}
func TestDebugLookup(t *testing.T) {
etc := newEtcdMiddleware()
etc.Debugging = true

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@@ -5,6 +5,7 @@ import (
"github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/etcd/msg"
"github.com/miekg/coredns/middleware/pkg/debug"
"github.com/miekg/coredns/middleware/pkg/dnsutil"
"github.com/miekg/coredns/request"
@@ -21,10 +22,10 @@ func (e *Etcd) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (
}
name := state.Name()
if e.Debugging {
if debug := isDebug(name); debug != "" {
if bug := debug.IsDebug(name); bug != "" {
opt.Debug = r.Question[0].Name
state.Clear()
state.Req.Question[0].Name = debug
state.Req.Question[0].Name = bug
}
}

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@@ -48,3 +48,24 @@ proxy . dns.google.com {
upstream /etc/resolv.conf
}
~~~
## Debug queries
Debug queries are enabled by default and currently there is no way to turn them off. When CoreDNS
receives a debug queries (i.e. the name is prefixed with `o-o.debug.` a TXT record with Comment from
`dns.google.com` is added. Note this is not always set, but sometimes you'll see:
`dig @localhost -p 1053 mx o-o.debug.example.org`:
~~~ txt
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;o-o.debug.example.org. IN MX
;; AUTHORITY SECTION:
example.org. 1799 IN SOA sns.dns.icann.org. noc.dns.icann.org. 2016110711 7200 3600 1209600 3600
;; ADDITIONAL SECTION:
. 0 CH TXT "Response from 199.43.133.53"
~~~

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@@ -12,7 +12,9 @@ import (
"sync/atomic"
"time"
"github.com/miekg/coredns/middleware/pkg/debug"
"github.com/miekg/coredns/middleware/proxy"
"github.com/miekg/coredns/request"
"github.com/miekg/dns"
)
@@ -30,11 +32,17 @@ type google struct {
func newGoogle() *google { return &google{client: newClient(ghost), quit: make(chan bool)} }
func (g *google) Exchange(req *dns.Msg) (*dns.Msg, error) {
func (g *google) Exchange(state request.Request) (*dns.Msg, error) {
v := url.Values{}
v.Set("name", req.Question[0].Name)
v.Set("type", fmt.Sprintf("%d", req.Question[0].Qtype))
v.Set("name", state.Name())
v.Set("type", fmt.Sprintf("%d", state.QType()))
optDebug := false
if bug := debug.IsDebug(state.Name()); bug != "" {
optDebug = true
v.Set("name", bug)
}
start := time.Now()
@@ -60,12 +68,20 @@ func (g *google) Exchange(req *dns.Msg) (*dns.Msg, error) {
return nil, err
}
m, err := toMsg(gm)
m, debug, err := toMsg(gm)
if err != nil {
return nil, err
}
m.Id = req.Id
if optDebug {
// reset question
m.Question[0].Name = state.QName()
// prepend debug RR to the additional section
m.Extra = append([]dns.RR{debug}, m.Extra...)
}
m.Id = state.Req.Id
return m, nil
}
@@ -223,8 +239,11 @@ func (g *google) do(addr, json string) ([]byte, error) {
return buf, nil
}
func toMsg(g *googleMsg) (*dns.Msg, error) {
// toMsg converts a googleMsg into the dns message. The returned RR is the comment disquised as a TXT
// record.
func toMsg(g *googleMsg) (*dns.Msg, dns.RR, error) {
m := new(dns.Msg)
m.Response = true
m.Rcode = g.Status
m.Truncated = g.TC
m.RecursionDesired = g.RD
@@ -243,23 +262,24 @@ func toMsg(g *googleMsg) (*dns.Msg, error) {
for i := 0; i < len(m.Answer); i++ {
m.Answer[i], err = toRR(g.Answer[i])
if err != nil {
return nil, err
return nil, nil, err
}
}
for i := 0; i < len(m.Ns); i++ {
m.Ns[i], err = toRR(g.Authority[i])
if err != nil {
return nil, err
return nil, nil, err
}
}
for i := 0; i < len(m.Extra); i++ {
m.Extra[i], err = toRR(g.Additional[i])
if err != nil {
return nil, err
return nil, nil, err
}
}
return m, nil
txt, _ := dns.NewRR(". 0 CH TXT " + g.Comment)
return m, txt, nil
}
func toRR(g googleRR) (dns.RR, error) {

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@@ -27,9 +27,9 @@ func (p *Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg)
start := time.Now()
state := request.Request{W: w, Req: r}
reply, backendErr := p.e.Exchange(r)
reply, backendErr := p.e.Exchange(state)
if backendErr == nil {
if backendErr == nil && reply != nil {
state.SizeAndDo(reply)
w.WriteMsg(reply)

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@@ -2,6 +2,7 @@ package httpproxy
import (
"io/ioutil"
"log"
"os"
"strings"
"testing"
@@ -9,7 +10,9 @@ import (
"github.com/mholt/caddy"
)
func TestSetupChaos(t *testing.T) {
func TestSetupHttpproxy(t *testing.T) {
log.SetOutput(ioutil.Discard)
tests := []struct {
input string
shouldErr bool
@@ -55,7 +58,6 @@ func TestSetupChaos(t *testing.T) {
}
if err != nil {
t.Logf("%q", err)
if !test.shouldErr {
t.Errorf("Test %d: Expected no error but found one for input %s. Error was: %v", i, test.input, err)
}

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@@ -5,13 +5,14 @@ import (
"net/http"
"time"
"github.com/miekg/coredns/request"
"github.com/miekg/dns"
)
// Exchanger is an interface that specifies a type implementing a DNS resolver that
// uses a HTTPS server.
type Exchanger interface {
Exchange(*dns.Msg) (*dns.Msg, error)
Exchange(request.Request) (*dns.Msg, error)
SetUpstream(*simpleUpstream) error
OnStartup() error

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@@ -25,7 +25,7 @@ func (m *Metrics) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
rw := dnsrecorder.New(w)
status, err := m.Next.ServeDNS(ctx, rw, r)
vars.Report(state, zone, rcode.ToString(rw.Rcode), rw.Size, rw.Start)
vars.Report(state, zone, rcode.ToString(rw.Rcode), rw.Len, rw.Start)
return status, err
}

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@@ -10,7 +10,7 @@ import (
// Report reports the metrics data associcated with request.
func Report(req request.Request, zone, rcode string, size int, start time.Time) {
// Proto and Family
// Proto and Family.
net := req.Proto()
fam := "1"
if req.Family() == 2 {
@@ -33,7 +33,7 @@ func Report(req request.Request, zone, rcode string, size int, start time.Time)
}
ResponseSize.WithLabelValues(zone, net).Observe(float64(size))
RequestSize.WithLabelValues(zone, net).Observe(float64(req.Size()))
RequestSize.WithLabelValues(zone, net).Observe(float64(req.Len()))
ResponseRcode.WithLabelValues(zone, rcode).Inc()
}

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@@ -0,0 +1,20 @@
package debug
import "strings"
const Name = "o-o.debug."
// IsDebug checks if name is a debugging name, i.e. starts with o-o.debug.
// it returns the empty string if it is not a debug message, otherwise it will return the
// name with o-o.debug. stripped off. Must be called with name lowercased.
func IsDebug(name string) string {
if len(name) == len(Name) {
return ""
}
name = strings.ToLower(name)
debug := strings.HasPrefix(name, Name)
if !debug {
return ""
}
return name[len(Name):]
}

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@@ -0,0 +1,21 @@
package debug
import (
"strings"
"testing"
)
func TestIsDebug(t *testing.T) {
if ok := IsDebug("o-o.debug.miek.nl."); ok != "miek.nl." {
t.Errorf("expected o-o.debug.miek.nl. to be debug")
}
if ok := IsDebug(strings.ToLower("o-o.Debug.miek.nl.")); ok != "miek.nl." {
t.Errorf("expected o-o.Debug.miek.nl. to be debug")
}
if ok := IsDebug("i-o.debug.miek.nl."); ok != "" {
t.Errorf("expected i-o.Debug.miek.nl. to be non-debug")
}
if ok := IsDebug(strings.ToLower("i-o.Debug.")); ok != "" {
t.Errorf("expected o-o.Debug. to be non-debug")
}
}

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@@ -16,7 +16,7 @@ import (
type Recorder struct {
dns.ResponseWriter
Rcode int
Size int
Len int
Msg *dns.Msg
Start time.Time
}
@@ -39,16 +39,16 @@ func (r *Recorder) WriteMsg(res *dns.Msg) error {
r.Rcode = res.Rcode
// We may get called multiple times (axfr for instance).
// Save the last message, but add the sizes.
r.Size += res.Len()
r.Len += res.Len()
r.Msg = res
return r.ResponseWriter.WriteMsg(res)
}
// Write is a wrapper that records the size of the message that gets written.
// Write is a wrapper that records the length of the message that gets written.
func (r *Recorder) Write(buf []byte) (int, error) {
n, err := r.ResponseWriter.Write(buf)
if err == nil {
r.Size += n
r.Len += n
}
return n, err
}

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@@ -53,7 +53,7 @@ func New(r *dns.Msg, rr *dnsrecorder.Recorder, emptyValue string) Replacer {
rcode = strconv.Itoa(rr.Rcode)
}
rep.replacements["{rcode}"] = rcode
rep.replacements["{size}"] = strconv.Itoa(rr.Size)
rep.replacements["{size}"] = strconv.Itoa(rr.Len)
rep.replacements["{duration}"] = time.Since(rr.Start).String()
}

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@@ -3,6 +3,7 @@ package root
import (
"fmt"
"io/ioutil"
"log"
"os"
"path/filepath"
"strings"
@@ -14,6 +15,8 @@ import (
)
func TestRoot(t *testing.T) {
log.SetOutput(ioutil.Discard)
// Predefined error substrings
parseErrContent := "Parse error:"
unableToAccessErrContent := "Unable to access root path"

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@@ -106,7 +106,10 @@ func (r *Request) Do() bool {
return false
}
// Size returns if UDP buffer size advertised in the requests OPT record.
// Len returns the length in bytes in the request.
func (r *Request) Len() int { return r.Req.Len() }
// Size returns if buffer size *advertised* in the requests OPT record.
// Or when the request was over TCP, we return the maximum allowed size of 64K.
func (r *Request) Size() int {
if r.size != 0 {