forked from mushorg/go-dpi
/
mqtt.go
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/
mqtt.go
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package classifiers
import (
"strings"
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/nayyara-samuel/go-dpi/types"
)
// MQTTClassifier struct
type MQTTClassifier struct{}
// HeuristicClassify for MQTTClassifier
func (classifier MQTTClassifier) HeuristicClassify(flow *types.Flow) bool {
return checkFirstPayload(flow.GetPackets(), layers.LayerTypeTCP,
func(payload []byte, packetsRest []gopacket.Packet) bool {
//check Control packet (connect)
if len(payload) < 6 {
// at least 6 packets
// 0x10 0x04 0x00 0x00 M Q
return false
}
isValidPacket := payload[0] == 0x10
//check message lenght
isValidLenght := int(payload[1]) == len(payload[2:])
protocolNameStr := string(payload[4:])
//check protocol name
isValidMQTT := strings.HasPrefix(protocolNameStr, "MQ")
return isValidMQTT && isValidLenght && isValidPacket
})
}
// GetProtocol returns the corresponding protocol
func (classifier MQTTClassifier) GetProtocol() types.Protocol {
return types.MQTT
}