dnstap

README

dnstap

dnstap enables logging to dnstap, a flexible, structured binary log format for DNS software: http://dnstap.info.

There is a buffer, expect at least 13 requests before the server sends its dnstap messages to the socket.

Syntax

dnstap SOCKET [full]

• SOCKET is the socket path supplied to the dnstap command line tool.
• full to include the wire-format DNS message.

Examples

Log information about client requests and responses to /tmp/dnstap.sock.

dnstap /tmp/dnstap.sock

Log information including the wire-format DNS message about client requests and responses to /tmp/dnstap.sock.

dnstap unix:///tmp/dnstap.sock full

Log to a remote endpoint.

dnstap tcp://127.0.0.1:6000 full

Dnstap command line tool

% go get github.com/dnstap/golang-dnstap
% cd $GOPATH/src/github.com/dnstap/golang-dnstap/dnstap
% go build
% ./dnstap

The following command listens on the given socket and decodes messages to stdout.

% dnstap -u /tmp/dnstap.sock

The following command listens on the given socket and saves message payloads to a binary dnstap-format log file.

% dnstap -u /tmp/dnstap.sock -w /tmp/test.dnstap

Listen for dnstap messages on port 6000.

% dnstap -l 127.0.0.1:6000

Documentation

Index

• type ContextKey
• type Dnstap
  • func (h Dnstap) Name() string
  • func (h Dnstap) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error)
  • func (h Dnstap) TapBuilder() msg.Builder
  • func (h Dnstap) TapMessage(m *tap.Message) error
• type IORoutine
• type Tapper
  • func TapperFromContext(ctx context.Context) (t Tapper)

Types

type ContextKey

type ContextKey string

ContextKey defines the type of key that is used to save data into the context

const (
	// DnstapSendOption specifies the Dnstap message to be send.  Default is sent all.
	DnstapSendOption ContextKey = "dnstap-send-option"
)

type Dnstap

type Dnstap struct {
	Next plugin.Handler
	IO   IORoutine
	Pack bool
}

Dnstap is the dnstap handler.

func (Dnstap) Name

func (h Dnstap) Name() string

Name returns dnstap.

func (Dnstap) ServeDNS

func (h Dnstap) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error)

ServeDNS logs the client query and response to dnstap and passes the dnstap Context.

func (Dnstap) TapBuilder

func (h Dnstap) TapBuilder() msg.Builder

TapBuilder implements Tapper.

func (Dnstap) TapMessage

func (h Dnstap) TapMessage(m *tap.Message) error

TapMessage implements Tapper.

type IORoutine

type IORoutine interface {
	Dnstap(tap.Dnstap)
}

IORoutine is the dnstap I/O thread as defined by: <http://dnstap.info/Architecture>.

type Tapper

type Tapper interface {
	TapMessage(*tap.Message) error
	TapBuilder() msg.Builder
}

Tapper is implemented by the Context passed by the dnstap handler.

func TapperFromContext

func TapperFromContext(ctx context.Context) (t Tapper)

TapperFromContext will return a Tapper if the dnstap plugin is enabled.