Mirrors/coredns
1
0
Fork 0
mirror of https://github.com/coredns/coredns.git synced 2025-11-17 17:32:18 -05:00
Code Issues Packages Projects Releases Wiki Activity

middleware/proxy: dnstap (#786)

Browse Source 
* experimental dnstap support into proxy

* proxy reports dnstap errors

* refactoring

* add a message builder for less dnstap code

* msg lint

* context

* proxy by DNS: dnstap comments

* TapBuilder

* resolves conflict

* dnstap into ServeDNS

* testing

* more tests

* `go lint`

* doc update
This commit is contained in:
varyoo
2017-09-01 12:41:41 +02:00
committed by Miek Gieben
parent 8f77566cdd
commit c5efd45720
13 changed files with 317 additions and 97 deletions
Download Patch File Download Diff File Expand all files Collapse all files

77
middleware/dnstap/taprw/writer.go
View File

@@ -6,79 +6,68 @@ import (
"fmt"
"github.com/coredns/coredns/middleware/dnstap/msg"
"github.com/coredns/coredns/request"
tap "github.com/dnstap/golang-dnstap"
"github.com/miekg/dns"
)
type Taper interface {
// Tapper is what ResponseWriter needs to log to dnstap.
type Tapper interface {
TapMessage(m *tap.Message) error
TapBuilder() msg.Builder
}
// ResponseWriter captures the client response and logs the query to dnstap.
// Single request use.
type ResponseWriter struct {
queryData msg.Data
Query *dns.Msg
queryEpoch uint64
Query *dns.Msg
dns.ResponseWriter
Taper
Pack bool
err error
Tapper
err error
}
// Check if a dnstap error occurred.
// Set during ResponseWriter.Write.
// DnstapError check if a dnstap error occurred during Write and returns it.
func (w ResponseWriter) DnstapError() error {
return w.err
}
// To be called as soon as possible.
// QueryEpoch sets the query epoch as reported by dnstap.
func (w *ResponseWriter) QueryEpoch() {
w.queryData.Epoch()
w.queryEpoch = msg.Epoch()
}
// Write back the response to the client and THEN work on logging the request
// WriteMsg writes back the response to the client and THEN works on logging the request
// and response to dnstap.
// Dnstap errors to be checked by DnstapError.
func (w *ResponseWriter) WriteMsg(resp *dns.Msg) error {
writeErr := w.ResponseWriter.WriteMsg(resp)
// Dnstap errors are to be checked by DnstapError.
func (w *ResponseWriter) WriteMsg(resp *dns.Msg) (writeErr error) {
writeErr = w.ResponseWriter.WriteMsg(resp)
writeEpoch := msg.Epoch()
if err := tapQuery(w); err != nil {
b := w.TapBuilder()
b.TimeSec = w.queryEpoch
if err := func() (err error) {
err = b.AddrMsg(w.ResponseWriter.RemoteAddr(), w.Query)
if err != nil {
return
}
return w.TapMessage(b.ToClientQuery())
}(); err != nil {
w.err = fmt.Errorf("client query: %s", err)
// don't forget to call DnstapError later
}
if writeErr == nil {
if err := tapResponse(w, resp); err != nil {
if err := func() (err error) {
b.TimeSec = writeEpoch
if err = b.Msg(resp); err != nil {
return
}
return w.TapMessage(b.ToClientResponse())
}(); err != nil {
w.err = fmt.Errorf("client response: %s", err)
}
}
return writeErr
}
func tapQuery(w *ResponseWriter) error {
req := request.Request{W: w.ResponseWriter, Req: w.Query}
if err := w.queryData.FromRequest(req); err != nil {
return err
}
if w.Pack {
if err := w.queryData.Pack(w.Query); err != nil {
return fmt.Errorf("pack: %s", err)
}
}
return w.Taper.TapMessage(w.queryData.ToClientQuery())
}
func tapResponse(w *ResponseWriter, resp *dns.Msg) error {
d := &msg.Data{}
d.Epoch()
req := request.Request{W: w, Req: resp}
if err := d.FromRequest(req); err != nil {
return err
}
if w.Pack {
if err := d.Pack(resp); err != nil {
return fmt.Errorf("pack: %s", err)
}
}
return w.Taper.TapMessage(d.ToClientResponse())
return
}