/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package dnstap
import (
"bytes"
"encoding/json"
"fmt"
"net"
"time"
"github.com/miekg/dns"
)
type jsonTime time.Time
func (jt *jsonTime) MarshalJSON() ([]byte, error) {
stamp := time.Time(*jt).Format(time.RFC3339Nano)
return []byte(fmt.Sprintf("\"%s\"", stamp)), nil
}
type jsonDnstap struct {
Type string `json:"type"`
Identity string `json:"identity,omitempty"`
Version string `json:"version,omitempty"`
Message jsonMessage `json:"message"`
}
type jsonMessage struct {
Type string `json:"type"`
QueryTime *jsonTime `json:"query_time,omitempty"`
ResponseTime *jsonTime `json:"response_time,omitempty"`
SocketFamily string `json:"socket_family,omitempty"`
SocketProtocol string `json:"socket_protocol,omitempty"`
QueryAddress *net.IP `json:"query_address,omitempty"`
ResponseAddress *net.IP `json:"response_address,omitempty"`
QueryPort uint32 `json:"query_port,omitempty"`
ResponsePort uint32 `json:"response_port,omitempty"`
QueryZone string `json:"query_zone,omitempty"`
QueryMessage string `json:"query_message,omitempty"`
ResponseMessage string `json:"response_message,omitempty"`
}
func convertJSONMessage(m *Message) jsonMessage {
jMsg := jsonMessage{
Type: fmt.Sprint(m.Type),
SocketFamily: fmt.Sprint(m.SocketFamily),
SocketProtocol: fmt.Sprint(m.SocketProtocol),
}
if m.QueryTimeSec != nil && m.QueryTimeNsec != nil {
qt := jsonTime(time.Unix(int64(*m.QueryTimeSec), int64(*m.QueryTimeNsec)).UTC())
jMsg.QueryTime = &qt
}
if m.ResponseTimeSec != nil && m.ResponseTimeNsec != nil {
rt := jsonTime(time.Unix(int64(*m.ResponseTimeSec), int64(*m.ResponseTimeNsec)).UTC())
jMsg.ResponseTime = &rt
}
if m.QueryAddress != nil {
qa := net.IP(m.QueryAddress)
jMsg.QueryAddress = &qa
}
if m.ResponseAddress != nil {
ra := net.IP(m.ResponseAddress)
jMsg.ResponseAddress = &ra
}
if m.QueryPort != nil {
jMsg.QueryPort = *m.QueryPort
}
if m.ResponsePort != nil {
jMsg.ResponsePort = *m.ResponsePort
}
if m.QueryZone != nil {
name, _, err := dns.UnpackDomainName(m.QueryZone, 0)
if err != nil {
jMsg.QueryZone = fmt.Sprintf("parse failed: %v", err)
} else {
jMsg.QueryZone = string(name)
}
}
if m.QueryMessage != nil {
msg := new(dns.Msg)
err := msg.Unpack(m.QueryMessage)
if err != nil {
jMsg.QueryMessage = fmt.Sprintf("parse failed: %v", err)
} else {
jMsg.QueryMessage = msg.String()
}
}
if m.ResponseMessage != nil {
msg := new(dns.Msg)
err := msg.Unpack(m.ResponseMessage)
if err != nil {
jMsg.ResponseMessage = fmt.Sprintf("parse failed: %v", err)
} else {
jMsg.ResponseMessage = msg.String()
}
}
return jMsg
}
// JSONFormat renders a Dnstap message in JSON format. Any encapsulated
// DNS messages are rendered as strings in a format similar to 'dig' output.
func JSONFormat(dt *Dnstap) (out []byte, ok bool) {
var s bytes.Buffer
j, err := json.Marshal(jsonDnstap{
Type: fmt.Sprint(dt.Type),
Identity: string(dt.Identity),
Version: string(dt.Version),
Message: convertJSONMessage(dt.Message),
})
if err != nil {
return nil, false
}
s.WriteString(string(j) + "\n")
return s.Bytes(), true
}