Research On Key Technologies Of Reverse Analysis Of Private Flight Control Protocols Of Lightweight UAVs

While the use of civil unmanned aerial vehicles(UAVs)has increased considerably in recent years,however,a UAV can also be used for inappropriate applications.UAV abuse cases,such as flight safety regulations and no-fly area violations,pose a growing threat to public safety and privacy.Therefore,airspace administrators urgently need an effective method to regulate UAVs.It is an effective way to regulate UAVs by information network confrontations(i.e.fabricating the flight control commands,sending to the non-cooperative UAV and hijacking the flight control links of it).But the UAV manufacturers generally develop their own private flight control protocols and do not open to the public,which makes it difficult for the management authority to fabricate the corresponding flight control commands.Therefore,how to acquire the information of the UAV flight control protocol under the circumstance where lacking prior knowledge is crucial to regulate UAVs by means of information confrontation.The thesis proposes a method to analyze the private flight control protocols of UAVs reversely by automatical reverse analysis technologies of private network protocols.Firstly,we classify flight control commands collected from a binary network trace into clusters;then,we analyze the meaning of flight control commands by the accumulated error of each cluster;subsequently,we extract the binary format of commands and infer field semantics in these commands;and finally,we forge the flight control commands into the flight control link to achieve the hijacking of UAVs.By this way,can we realize effective regulation of UAVs.Here are the main works of this thesis:(1)A reverse analysis framework of flight control protocols based on automatical reverse analysis of private network protocols.As a result of lacking open research on reverse analysis of UAVs flight control protocols,effective and complete flight control protocol reverse analysis method is rare.We presents an analysis system which clarifies the technical route of reverse analysis of UAVs flight control protocols.(2)A algorithm extracting the meaning of flight control commands by accumulated error.It is used to analyze the meaning of flight control commands based on the corresponding relationship between the certain flight action and the received commands.The method measures the corresponding relationship according to the time accumulated error.We extracted taking off,landing etc.commands.(3)A algorithm inferring the generator matrix of the check field in flight control commands.We propose a method to reverse-analyze how the target UAV generates check values and what the generator matrix is in affine space without the aforementioned prior knowledge.We also validate the obtained generator matrix by comparing the constructed check values with those collected from the network trace.Finally,we designed a UAVs regulation prototype system for a certain UAV successfully.