CN115134123A - Civil aviation ACARS ground-air data link anonymous secure session method and device - Google Patents

Abstract

The present application discloses a civil aviation ACARS ground-air data link anonymous security session method and device, wherein the method includes: receiving a ground station identity message broadcast by a ground station; sending a first message by the ground station, wherein the first message includes a first initial vector; receiving a second message sent by the ground station; verifying the second message, in the case of passing the verification, according to the first An initial vector is used to generate an anonymous identity database, wherein the anonymous identity database includes N first anonymous identities, where N is a positive integer greater than or equal to 1; a session is conducted with the ground station based on the anonymous identity database. This application can effectively guarantee the confidentiality, privacy and authentication of civil aviation ACARS messages.

Description

A kind of civil aviation ACARS ground-air data link anonymous security session method and device

technical field

The present application relates to the field of information security, and in particular, to a method and device for an anonymous secure session of a civil aviation ACARS ground-air data link.

Background technique

ACARS (Aircrat Communications Addressing and Reporting System) is a data link communication system that transmits short messages by radio or satellite between aircraft and ground stations. It is currently the most widely used worldwide. civil aviation communication system. The vast majority of countries in the world, including my country, adopt the protocol used by the ACARS system is the ARINC-618 protocol (VHF communication air-ground protocol). In the air channel, through any protocol transmission without any encryption and authentication mechanism, the confidentiality, integrity and non-repudiation of the civil aviation data link information cannot be guaranteed, and the civil aviation data link is vulnerable to eavesdropping, deception, disguise, information tampering, replay Threat of waiting for attack. These possible attacks will steal the privacy and confidentiality of civil aviation system practitioners and users, and even destroy the normal operation of the civil aviation system, resulting in significant loss of personnel and property. Therefore, the importance of protecting the security of civil aviation data links cannot be ignored.

The security of ACARS ground-air data link messages is gradually receiving attention. Some researches use symmetric cryptosystem to encrypt the text field of the message to achieve message confidentiality, and use asymmetric cryptosystem to protect the non-repudiation (authentication) of the message. One of the most representative is the ACARS Message Security (ACARS Message Security, AMS) system proposed in the ARINC-823P1 standard by ARINC (Aeronautical Radio Inc., aeronautical radio communication company) to protect message confidentiality and identity authentication.

The privacy of civil aviation identities in air-to-ground data link messages such as ACARS has also received attention. Conformal encryption is a special kind of symmetric encryption algorithm, which can ensure that the encrypted ciphertext format is exactly the same as the plaintext format before encryption, so it has the advantages of not needing to change the database paradigm and being transparent to upper-layer applications. Encryption is used in another ground-to-air communication link, ADS-B (Automatic dependent surveillance-broadcast).

In the ACARS message, there are two fields that need to be protected, ARN (Aircraft Registration Number, aircraft registration number) and Text (message). The ARN in the control field is the 7-digit aircraft registration code, which is the unique identification of the aircraft; the text field of the message can carry text information of no more than 220 characters, and the format of the information can use the prescribed template or can be freely defined. The downlink Text field is divided into three subfields: the message serial number MSN, the aircraft identity Flight ID, and the free message FreeText. The Flight ID and Free Text need to be protected.

The security protection scheme of Text field represented by AMS system cannot protect the privacy of aircraft identity. Although the content of the message is encrypted, the attacker can still infer the flight information of the aircraft based on the identity of the aircraft in the current airspace, and even spy on the political or commercial secrets in it.

The use of conformal encryption for ground-air data links can protect aircraft privacy to a certain extent, but when the aircraft has many conversations with the ground station, after the attacker has mastered its statistical characteristics, he can still speculate on the behavior of the aircraft, which is very important for civil aviation. security poses a threat.

To sum up, in the prior art, the confidentiality, privacy and authentication of civil aviation ACARS messages cannot be effectively guaranteed.

Application content

The present application aims to solve one of the technical problems in the related art at least to a certain extent.

Therefore, the purpose of this application is to solve the problem that the confidentiality, privacy and authentication of civil aviation ACARS messages cannot be effectively guaranteed in the prior art, and proposes an anonymous secure session method for civil aviation ACARS ground-air data link.

Another object of the present application is to propose an anonymous secure session device for civil aviation ACARS ground-air data link.

In order to achieve the above purpose, on the one hand, the present application proposes a method for an anonymous secure session of the civil aviation ACARS ground-air data link, which includes the following steps:

Receive the ground station identity message broadcast by the ground station;

Sending a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, wherein the first message includes a first initial vector;

receiving a second message sent by the ground station;

Verifying the second message, in the case of passing the verification, generating an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous identities, and N is a positive integer greater than or equal to 1;

A session is conducted with the ground station based on the anonymous identity repository.

In some possible embodiments, the sending the first message to the ground station through an asymmetric key mechanism based on the ground station identity information includes:

Determine the public key of the ground station according to the identity information of the ground station;

generating the first initial vector, the session key, and recording the timestamp of the current time;

generating a second anonymous identity of the aircraft through the public key of the ground station according to the aircraft registration number and the session key;

generating a first signature through the private key of the aircraft according to the first initial vector, the session key, the timestamp and the aircraft registration number;

generating a first ciphertext through the public key of the ground station according to the first initial vector, the session key, the timestamp and the first signature;

Replacing the aircraft registration number in the first message with the second anonymous identity of the aircraft, and after filling the message segment in the first message with the first ciphertext, send a message to the ground The station sends the first message.

In some possible embodiments, the verifying the second message includes:

Obtain a second signature through the second message;

The second signature is verified by the public key of the ground station.

In some possible embodiments, when the verification is passed, generating an anonymous identity database according to the first initial vector includes:

Add one to the first initial vector in turn to generate N identity vectors, where N is a positive integer greater than or equal to 1;

generating the N first anonymous identities of the aircraft according to the aircraft registration number, the session key and the N identity vectors;

The anonymous identity database is formed based on the N first anonymous identities.

In some possible embodiments, conducting a session with the ground station based on the anonymous identity database includes:

generating a third message based on the anonymous identity repository;

sending the third message to the ground station;

A fourth message sent by the ground station is received.

In some possible embodiments, the generating the third message based on the anonymous identity repository includes:

generating a first plaintext and a first message sequence number, and calculating a first hash value of the first plaintext and the first message sequence number;

Calculate a second initial vector of the third message according to the first message sequence number and the first initial vector;

generating a second ciphertext by using the session key according to the first plaintext, the first hash value and the second initial vector;

Selecting a third anonymous identity through a random number algorithm in the anonymous identity database;

Replacing the aircraft registration number in the third message with a third anonymous identity, and after filling the segment in the third message with the second ciphertext, sending the ground station the Third message.

In some possible embodiments, the receiving the fourth message sent by the ground station includes:

obtaining a fourth anonymous identity in the fourth message;

looking up the fourth anonymous identity in the anonymous identity repository;

In the case that the fourth anonymous identity is found in the anonymous identity database, query the first initial vector and the session key corresponding to the fourth anonymous identity;

obtaining the sequence number of the second message in the fourth message;

Calculate the third initial vector of the fourth message according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number;

Obtain the third ciphertext in the fourth message, decrypt the third ciphertext according to the session key and the third initial vector, and obtain the second plaintext and the second hash value;

calculating a third hash value of the second plaintext and the second message sequence number;

verifying that the third hash value is equal to the second hash value;

In the case that the third hash value is equal to the second hash value, the second plaintext is processed, and in the case that the third hash value is not equal to the second hash value, The fourth message is discarded.

In some possible embodiments, after searching the fourth anonymous identity in the anonymous identity database, the method further includes:

If the fourth anonymous identity cannot be found in the anonymous identity database, the fourth message is discarded.

In some possible embodiments, before determining the public key of the ground station according to the identity information of the ground station, the method includes:

The identity information of the ground station and the public key corresponding to the identity information of the ground station are obtained through the certification center.

In order to achieve the above-mentioned purpose, the present application proposes, on the other hand, an anonymous security session device for civil aviation ACARS ground-air data link, including:

a first receiving module, configured to receive the ground station identity message broadcast by the ground station;

a sending module, configured to send a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, wherein the first message includes a first initial vector;

a second receiving module, configured to receive the second message sent by the ground station;

A verification module, configured to verify the second message, and in the case of passing the verification, generate an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous identities, and N is greater than or equal to a positive integer of 1;

A session module, configured to conduct a session with the ground station based on the anonymous identity database.

Beneficial effects of this application:

According to the civil aviation ACARS ground-air data link anonymous security session method according to the embodiment of the present application, the ground station identity message broadcasted by the ground station is received; the first message is sent to the ground station through the asymmetric key mechanism based on the ground station identity message, wherein the first message is a message including a first initial vector; receiving a second message sent by the ground station; verifying the second message, and in the case of passing the verification, generating an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous Identity, N is a positive integer greater than or equal to 1; conducts a conversation with the ground station based on the anonymous identity database. This application can effectively guarantee the confidentiality, privacy and authentication of civil aviation ACARS messages.

Additional aspects and advantages of the present application will be set forth, in part, in the following description, and in part will be apparent from the following description, or learned by practice of the present application.

Description of drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily understood from the following description of embodiments taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a flowchart of a method for an anonymous secure session of civil aviation ACARS ground-air data link according to an embodiment of the present application;

FIG. 2 is a schematic diagram of session establishment according to an embodiment of the present application;

3 is a schematic diagram of an aircraft anonymous identity database generation process according to an embodiment of the present application;

FIG. 4 is a schematic diagram of an ACARS anonymous secure session protocol downlink according to an embodiment of the present application;

5 is a schematic diagram of an ACARS anonymous secure session protocol uplink according to an embodiment of the present application;

6 is a schematic diagram of an ACARS ground-air data security model according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of a civil aviation ACARS ground-air data link anonymous security session device according to an embodiment of the present application.

Detailed ways

It should be noted that the embodiments in the present application and the features of the embodiments may be combined with each other in the case of no conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

In order to make those skilled in the art better understand the solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only The embodiments are part of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the scope of protection of the present application.

The following describes the method and device for anonymous security session of civil aviation ACARS ground-air data link proposed according to the embodiments of the present application with reference to the accompanying drawings.

It should be noted that the symbols and function symbols that may be used in the anonymous secure session method of the civil aviation ACARS ground-air data link are shown in Table 1:

Table 1 Symbol and function symbol definitions

FIG. 1 is a flowchart of a method for an anonymous secure session of a civil aviation ACARS ground-air data link according to an embodiment of the present application.

As shown in Figure 1, the method for anonymous secure session of the civil aviation ACARS ground-air data link includes the following steps:

Step S110, receiving the ground station identity message broadcast by the ground station.

In the embodiment of this application, as shown in Figure 2, after the aircraft enters the airspace covered by the ground station, it can receive the ground station identity message broadcast by the ground station. The interval broadcast to the airspace it covers can be expressed as follows:

Message1:G→F:ID _G

Among them, Message1 represents the identity message of the ground station, G represents the ground station, F represents the aircraft, ID _G represents the identity of the ground station, and G→F:ID _G represents the identity of the ground station sent by the ground station to the aircraft.

Step S120, sending a first message to the ground station through an asymmetric key mechanism based on the ground station identity message.

The first message includes a first initial vector iv ₀ , the first message Message2 may be a session establishment request message sent by the aircraft to the ground station according to the ground station identity message after the aircraft receives the ground station identity message, and the first initial vector may be is the initial vector contained in the first message.

In this embodiment of the present application, after receiving the ground identity message broadcast by the ground station, the aircraft may send a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, where the first message is used to request the ground station to establish a session .

Step S130, receiving the second message sent by the ground station.

The second message Message3 may be a session establishment feedback message sent by the ground station to the aircraft after receiving the first message sent by the aircraft, and used to indicate that the aircraft ground station is ready for a session.

In this embodiment of the present application, after sending the first message to the ground station, the aircraft may receive the second message sent by the ground station, and the aircraft may learn whether the ground station is ready for a session according to the second message.

Step S140, verifying the second message, and in the case of passing the verification, generating an anonymous identity database according to the first initial vector.

The anonymous identity database includes N first anonymous identities AID ₁ , where N is a positive integer greater than or equal to 1, and the first anonymous identity is an anonymous identity generated by the aircraft according to the first initial vector, which is used to hide its real identity during the session. identity.

In this embodiment of the present application, after the aircraft receives the second message sent by the ground station, it can verify the second message, and if the verification is passed, it can be considered that the ground station is ready for a session, and generates an anonymous message according to the first initial vector. Identity database. The anonymous identity database includes N first anonymous identities. The aircraft can use the first anonymous identity in each subsequent session to hide its true identity and ensure the privacy of its true identity.

Step S150, start a session with the ground station based on the anonymous identity database.

In the embodiment of the present application, after the aircraft generates an anonymous identity database according to the first initial vector, it can conduct a session with the ground station based on the anonymous identity database, and the aircraft can inform the ground station of flight information such as the current flight altitude and flight status through the session process, The ground station can record the flight information of the aircraft through the session process.

According to the civil aviation ACARS ground-air data link anonymous security session method according to the embodiment of the present application, the ground station identity message broadcasted by the ground station is received; the first message is sent to the ground station through the asymmetric key mechanism based on the ground station identity message, wherein the first message is a message including a first initial vector; receiving a second message sent by the ground station; verifying the second message, and in the case of passing the verification, generating an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous Identity, N is a positive integer greater than or equal to 1; conducts a conversation with the ground station based on the anonymous identity database. This application can effectively guarantee the confidentiality, privacy and authentication of civil aviation ACARS messages.

In some possible embodiments, the first message is sent to the ground station through an asymmetric key mechanism based on the ground station identity information, including:

Determine the public key of the ground station according to the identity information of the ground station;

Generate the first initial vector, the session key, and record the timestamp of the current time;

Generate the second anonymous identity of the aircraft through the public key of the ground station according to the aircraft registration number and the session key;

Generate a first signature through the private key of the aircraft according to the first initial vector, the session key, the timestamp and the aircraft registration number;

Generate the first ciphertext through the public key of the ground station according to the first initial vector, the session key, the timestamp and the first signature;

After replacing the aircraft registration number in the first message with the second anonymous identity of the aircraft, and after filling the message segment in the first message into the first ciphertext, the first message is sent to the ground station.

Wherein, the second anonymous identity may be an anonymous identity generated by the aircraft through the public key of the ground station according to the aircraft registration number and the session key, which is used to hide the identity information of the aircraft itself before the session is established, and the first signature may be the The signature generated by the initial vector, session key, timestamp and aircraft registration number through the aircraft's private key is essentially a digital signature, which is used for signature verification by the ground station to confirm whether the received message has been tampered with. The ciphertext can be the ciphertext generated by the aircraft through the public key of the ground station according to the first initial vector, session key, timestamp and first signature. After the ciphertext is received by the ground station, it can be decrypted to obtain the first An initial vector, session key, timestamp and first signature.

In the embodiment of the present application, as shown in FIG. 2 , the aircraft enters the airspace of the ground station, and after receiving the ground station identity information broadcast by the ground station, the public key pk _G of the ground station can be determined according to the ground station identity information ID _G , And generate the first initial vector iv ₀ , the session key k _d and the timestamp t recording the current time for the session, and pass the public key pk of the ground station according to the aircraft registration number ARN and the generated session key k _d based on the public key encryption algorithm. _G can generate the second anonymous identity AID ₂ of the aircraft, ie AID ₂ =ENC(ARN, k _d ), and can also pass the aircraft through the aircraft according to the first initial vector iv ₀ , the session key k _d , the timestamp t and the aircraft registration number ARN The first signature is generated from the private key sk _F of Γ 1 , namely Γ _{1 =} SIG( _{iv 0} ||k _d ||t||ARN,sk _F ). The stamp t and the first signature Γ ₁ generate the first ciphertext C ₁ through the public key pk _G of the ground station, that is, C ₁ =ENC(iv ₀ ||k _d ||t||Γ ₁ ,pk _G ), The aircraft registration number in a message is replaced with the second anonymous identity of the aircraft, and after the segment in the first message is filled with the first ciphertext, a complete first message Message2 is generated, so that the first message can be sent to the ground station. message, the above process can be simply expressed as:

Message2:

In some possible embodiments, verifying the second message includes:

Obtain the second signature through the second message;

The second signature is verified by the public key of the ground station.

The second signature may be a signature performed by the ground station on the second message based on a signature algorithm, and the aircraft may learn whether the second message has been tampered with according to the verification result of the second signature.

In the embodiment of the present application, as shown in FIG. 2 , after the aircraft receives the second message sent by the ground station, it can obtain the second signature Γ ₂ through the second message, and then use the public key pk of the ground station based on the signature verification algorithm. _G verifies the second signature, namely VER(t||ARN||iv ₀ ||k _d ,pk _G ). If the verification is passed, the aircraft can determine that the ground station is ready for a session and can An initial vector generates an anonymous identity database. If the verification fails, the aircraft can consider that an attacker has tampered with the second message, so that the second message can be discarded.

It should be noted that, as shown in FIG. 2 , after receiving the first message sent by the aircraft, the ground station can decrypt the first ciphertext C ₁ with the private key sk _G of its own ground station to obtain the first initial vector iv ₀ , session key k _d , timestamp t and first signature Γ ₁ , namely DEC(C ₁ , sk _G ), AID ₂ can also be taken out from the control field, and the aircraft registration number, ie ARN, can be obtained by decrypting the session key =DEC(AID,k _d ), after obtaining the aircraft registration number, the ground station obtains the aircraft public key pk _F corresponding to the aircraft according to the aircraft registration number query, and then verifies the first signature with the aircraft public key based on the signature verification algorithm, namely VER (iv ₀ ||k _d ||t||ARN,Γ ₁ ,pk _F ), in the case of successful verification, the ground station can determine that the first message is not tampered by an attacker, thereby determining the session key and time of the aircraft stamp and aircraft registration number, the ground station can discard the first message in case of unsuccessful verification. After the ground station successfully verifies the first signature and determines the session key, timestamp and time registration number of the aircraft, the ground station can verify the freshness of the timestamp by comparing the difference between the determined timestamp and the timestamp of the current moment. Check whether the delay is within a reasonable range. If the delay is within a reasonable range, proceed to the next step. If the delay is not within a reasonable range, discard the first message and wait for the aircraft to send an updated first message. After determining that the delay is within a reasonable range, the ground station can use the ground station private key to sign the timestamp t, the aircraft registration number ARN, the first initial vector iv ₀ and the session key k _d based on the digital signature algorithm to obtain the second signature Γ ₂ , namely Γ ₂ =SIG(t||ARN||iv ₀ ||k _d , sk _G ), fill the second signature into the message field of the second message, and fill the second anonymous identity into the second message After controlling the field, a second message is sent to the aircraft. As shown in Figure 3, the ground station can also predict N anonymous identities used by the aircraft during the session according to the first initial vector, that is, AID _i =ENC(ARN,k _d ,iv _0i ), where N is a positive value greater than or equal to 1 Integer, specifically, the ground station can obtain N identity vectors by adding one to the first initial vector in turn, which can be understood as iv _0i =iv ₀ +i, 1≤i≤N, and then encrypt the identity vector with the session key Then, perform an XOR operation with the aircraft registration code to obtain an anonymous identity, and the obtained N anonymous identities constitute the anonymous identity database of the corresponding aircraft. The above second message sending process can be simply described as:

Message3:

In some possible embodiments, when the verification is passed, the anonymous identity database is generated according to the first initial vector, including:

Add one to the first initial vector in turn to generate N identity vectors, where N is a positive integer greater than or equal to 1;

Generate N first anonymous identities of the aircraft according to the aircraft registration number, session key and N identity vectors;

An anonymous identity database is formed based on the N first anonymous identities.

In the embodiment of the present application, when the aircraft passes the verification of the second message, the first initial vector can be added by one to generate N identity vectors, which can be understood as iv _0i =iv ₀ +i, 1≤i≤N , encrypt the N identity vectors respectively with the session key, and then perform XOR operation with the aircraft registration number to obtain N first anonymous identities, and form the N first anonymous identities into the aircraft's own anonymous identity database.

In some possible embodiments, conducting a session with the ground station based on an anonymous identity repository includes:

generating a third message based on the anonymous identity store;

sending a third message to the ground station;

The fourth message sent by the ground station is received.

The third message may be a session message generated by the aircraft based on the N first anonymous identities in the anonymous identity database, which is used to notify the ground station of the flight status of the aircraft itself, and the fourth message may be the third message received by the ground station according to the third A session message sent by the message to inform or instruct the aircraft of its response to the third message.

In the embodiment of the present application, after the aircraft forms its own anonymous identity database, it can generate a third message based on the anonymous identity database, and then send the third message to the ground station, so that the ground station can be notified of the flight status of the aircraft itself. After receiving the third message sent by the aircraft, the current flight status of the aircraft can be known, and a corresponding fourth message is generated based on the content of the third message, and the fourth message is sent to the aircraft, and the aircraft receives the fourth message sent by the ground station. Afterwards, the notification content or indication content made by the ground station according to the third message can be obtained.

In some possible embodiments, the third message is generated based on the anonymous identity repository, including:

generating the first plaintext and the first message sequence number, and calculating the first hash value of the first plaintext and the first message sequence number;

Calculate the second initial vector of the third message according to the first message sequence number and the first initial vector;

generating a second ciphertext through the session key according to the first plaintext, the first hash value and the second initial vector;

Select the third anonymous identity through random number algorithm in the anonymous identity database;

The third message is sent to the ground station after replacing the aircraft registration number in the third message with the third anonymous identity, and after filling the segment in the third message with the second ciphertext.

The first plaintext may be text content generated by the aircraft according to its current flight status, the first message sequence number may be the message sequence number corresponding to the third message, and the first hash value may be the The plaintext and the hash value generated by the sequence number of the first message. The ground station can verify whether the third message has been tampered with by verifying the first hash value. The second initial vector can be calculated by the aircraft according to the sequence number of the first message and the first initial vector. The obtained initial vector of the third message, the second ciphertext may be the ciphertext generated by the aircraft based on the encryption algorithm according to the first plaintext, the first hash value and the second initial vector through the session key, and the third anonymous identity may be the aircraft. One of the first anonymous identities randomly selected by a random number algorithm in its own anonymous identity database.

In the embodiment of the present application, as shown in FIG. 4 , after the aircraft determines that the ground station is ready for a session and generates an anonymous identity database, it can generate the first plaintext M ₁ and the first message sequence number MSN ₁ , and calculate the first The plaintext and the first hash value H ₁ of the first message sequence number, that is, H ₁ =Hash(M ₁ , MSN ₁ ). According to the first message sequence number and the first initial vector, the second initial value corresponding to the third message can be calculated The vector iv _i , namely iv _i =SM3(iv ₀ ||MSN ₁ ), generates the second ciphertext C ₁ according to the first plaintext, the first hash value and the second initial vector through the session key, that is, C ₁ =ENC (M ₁ ||H ₁ ,k _d ,iv _i ), randomly select one of the first anonymous identities in the anonymous identity database as the third anonymous identity through the random number algorithm, and replace the aircraft registration number in the third message with the first anonymous identity. Three anonymous identities, and after filling the segment in the third message into the second ciphertext, after generating a complete third message, the third message is sent to the ground station. The above process can be simply expressed as:

Message4:

It should be noted that, during the conversation between the aircraft and the ground station, an initial vector needs to be generated for each conversation message, but only the first initial vector is used for generating the anonymous identity database.

It should be noted that, as shown in FIG. 4, after the aircraft sends the third message to the ground station, the ground station can receive the third message, extract the third anonymous identity from the third message, and use the third anonymous identity in the anonymous identity according to the third anonymous identity. Find the same anonymous identity in the library, and in the case of finding the third anonymous identity, query the corresponding first initial vector iv ₀ , session key k _d and aircraft registration number ARN according to the third anonymous identity, and if the third anonymous identity cannot be found. In the case of three anonymous identities, the third message can be discarded. After querying and obtaining the first initial vector, session key and aircraft registration number corresponding to the third anonymous identity, the first message sequence number in the third message can also be extracted. According to the first initial vector and the first message sequence number The second initial vector corresponding to the third message can be calculated, and the session key is used to decrypt the calculated second initial vector and the first ciphertext to obtain the first plaintext and the first hash value. Based on the first plaintext and the first The message serial number calculates the hash value through the hash algorithm, that is, Hash(M ₁ , MSN ₁ ), and verifies whether the first hash value is equal to Hash(M ₁ , MSN ₁ ), and the first hash value is equal to Hash(M ₁ ). , MSN ₁ ), the next step is performed on the first plaintext, and when the first hash value is not equal to Hash(M ₁ , MSN ₁ ), the first message can be discarded.

It should be noted that during the conversation between the aircraft and the ground station, some fields in each session message require security protection, as shown in Table 2, in which the ARN, Text FlightID, and Text fields are fields that increase security protection, and the rest Fields can be transmitted in clear text:

Table 2 Security protection fields

In some possible embodiments, receiving the fourth message sent by the ground station includes:

Obtain the fourth anonymous identity in the fourth message;

Find a fourth anonymous identity in the anonymous identity repository;

In the case of finding the fourth anonymous identity in the anonymous identity database, query the first initial vector and session key corresponding to the fourth anonymous identity;

obtaining the sequence number of the second message in the fourth message;

Calculate the third initial vector of the fourth message according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number;

Obtain the third ciphertext in the fourth message, decrypt the third ciphertext according to the session key and the third initial vector, and obtain the second plaintext and the second hash value;

calculating a third hash value of the second plaintext and the second message sequence number;

Verify that the third hash value is equal to the second hash value;

If the third hash value is equal to the second hash value, the second plaintext is processed, and if the third hash value is not equal to the second hash value, the fourth message is discarded.

The fourth anonymous identity may be one of the anonymous identities randomly selected by the ground station in the anonymous identity database of the corresponding aircraft, the second message sequence number may be the message sequence number generated by the ground station for the fourth message, and the third initial vector may be is the third initial vector of the fourth message calculated by the aircraft according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number. The third ciphertext can be the third ciphertext generated by the ground station, and the second plaintext can be is the plaintext generated by the ground station, the second hash value may be the hash value calculated by the ground station, and the third hash value may be the hash value calculated by the aircraft through the hash algorithm according to the second plaintext and the second message serial number .

In the embodiment of the present application, as shown in FIG. 5 , after the aircraft sends the third message to the ground station, it can wait to receive the fourth message sent by the ground station, and after receiving the fourth message, it can obtain the fourth message from the fourth message. Anonymous identity, look up the fourth anonymous identity in its own anonymous identity database, and if the fourth anonymous identity is found in the anonymous identity database, query the first initial vector iv ₀ and the session key k _d corresponding to the fourth anonymous identity, and then Obtain the second message sequence number MSN2 from the fourth message, and calculate the third initial vector of the fourth message according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number, that is, iv _i =Hash(iv ₀ || MSN ₂ ), then obtain the third ciphertext in the fourth message, decrypt the third ciphertext according to the session key and the third initial vector, and obtain the second plaintext and the second hash value, that is, M ₂ ||H ₂ = DEC(C ₃ ,k _d ,iv _i ), calculate the third hash value H ₃ according to the second plaintext and the second message sequence number through the hash algorithm, and verify whether the third hash value and the second hash value are equal, That is, to verify that H ₃ =H ₂ , in the case that the third hash value is equal to the second hash value, the second plaintext is processed, and in the case that the third hash value is not equal to the second hash value, the third hash value is discarded. Four messages.

It should be noted that, before sending the fourth message, the ground station needs to generate the fourth message. Specifically, still as shown in FIG. 5 , the ground station can generate the second plaintext and the second message sequence number, and calculate the second hash value of the second plaintext and the second message sequence number, that is, H ₂ =Hash(M ₂ , MSN ₂ ), calculate the third initial vector of the fourth message according to the first initial vector and the second message sequence number, and generate the third initial vector according to the second plaintext, the second hash value, the third initial vector and the session key based on the encryption algorithm cipher text, randomly select one of the first anonymous identities in the anonymous identity database of the corresponding aircraft as the fourth anonymous identity through the random number algorithm, replace the aircraft registration number in the fourth message with the fourth anonymous identity, and replace the fourth message with the fourth anonymous identity. After the message segment in is filled into the third ciphertext, the complete fourth message is generated, and the fourth message is sent to the aircraft. The above process can be simply expressed as:

Message5:

In some possible embodiments, after searching the fourth anonymous identity in the anonymous identity database, the method further includes:

In the case that the fourth anonymous identity cannot be found in the anonymous identity database, the fourth message is discarded.

In the embodiment of the present application, the aircraft searches for the fourth anonymous identity in its own anonymous identity database. If the fourth anonymous identity database cannot be found, it can be determined that the received fourth message is not a message sent to itself, and the fourth anonymous identity can be discarded. Four messages.

In some possible embodiments, before determining the public key of the ground station according to the identity information of the ground station, the method includes:

Obtain the identity information of the ground station and the public key corresponding to the identity information of the ground station through the certification center.

In the embodiment of the present application, before determining the public key of the ground station according to the identity information of the ground station, the aircraft will first obtain the public key of the ground station. As shown in Figure 6, the public key infrastructure (Public Key Infrastructure, PKI) can be used to manage the public key, and the public key of the aircraft and the ground station can be transferred through the third-party trust organization - the Certificate Authority (CA), that is, the certificate issuing center. The keys are bound with their respective identity information. Before the session starts, according to the flight plan provided by the air traffic control center, the aircraft can know the public key and corresponding identity information of the ground station that the route may pass through through the CA. The aircraft's public key and the corresponding identity information. In this way, after the aircraft or the ground station receives the identity information of the counterparty, the corresponding public key of the counterparty can be queried according to the identity information of the counterparty.

It should be noted that the session key can be generated by the aircraft and sent to the ground station, or it can be sent to the ground station through the Diff-Hellman (Diffy-Hellman) protocol, the Joux tripartite key agreement (Yux) protocol, the BD second-round group Key agreement protocols such as the key agreement (Burmester, Desmedt, Burmester, Desmedt) protocol are negotiated and determined.

It should be noted that the symmetric encryption and decryption algorithm based on the session key may preferably be the SM4 symmetric encryption and decryption algorithm, or may be symmetric such as 3DES (Triple Data Encryption Algorithm, triple data encryption algorithm), AES (Advanced Encryption Standard, advanced encryption standard). Encryption and decryption algorithm. In addition, the digital signature algorithm, signature verification algorithm and asymmetric encryption and decryption algorithm can be preferably SM2 asymmetric encryption and decryption algorithm, or RSA (Ron Rivest, AdiShamir, Leonard Adleman, Ronald Rivest, Adi Shamir) , Leonard Aardman) and other asymmetric encryption and decryption algorithms.

In order to realize the above embodiment, as shown in FIG. 7 , this embodiment also provides a civil aviation ACARS ground-air data link anonymous security session device 700, the device 700 includes: a first receiving module 710, a sending module 720, a second A receiving module 730 , a verification module 740 , and a conversation module 750 .

a first receiving module 710, configured to receive the ground station identity message broadcast by the ground station;

A sending module 720, configured to send a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, where the first message includes a first initial vector;

A second receiving module 730, configured to receive the second message sent by the ground station;

A verification module 740, configured to verify the second message, and in the case of passing the verification, generate an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous identities, and N is a positive integer greater than or equal to 1;

The conversation module 750 is used to carry out a conversation with the ground station based on the anonymous identity database.

According to the civil aviation ACARS ground-air data link anonymous security session device according to the embodiment of the present application, the ground station identity message broadcasted by the ground station is received; based on the ground station identity message, the first message is sent to the ground station through an asymmetric key mechanism, wherein the first message is a message including a first initial vector; receiving a second message sent by the ground station; verifying the second message, and in the case of passing the verification, generating an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous Identity, N is a positive integer greater than or equal to 1; conducts a conversation with the ground station based on the anonymous identity database. This application can effectively guarantee the confidentiality, privacy and authentication of civil aviation ACARS messages.

In some possible embodiments, the sending module 720 includes:

a determining unit for determining the public key of the ground station according to the identity information of the ground station;

a first generating unit, used to generate a first initial vector, a session key, and record the timestamp of the current time;

The second generation unit is used to generate the second anonymous identity of the aircraft through the public key of the ground station according to the aircraft registration number and the session key;

The third generation unit generates a first signature through the private key of the aircraft according to the first initial vector, the session key, the timestamp and the aircraft registration number;

The fourth generation unit generates the first ciphertext through the public key of the ground station according to the first initial vector, the session key, the time stamp and the first signature;

A replacement unit, configured to replace the aircraft registration number in the first message with the second anonymous identity of the aircraft, and after filling the segment in the first message into the first ciphertext, send the first message to the ground station .

In some possible embodiments, the verification module 740 includes:

an obtaining unit, configured to obtain the second signature through the second message;

The first verification unit is used for verifying the second signature through the public key of the ground station.

In some possible embodiments, the verification module 740 further includes:

The fifth generation unit is used for adding one to the first initial vector in turn to generate N identity vectors, where N is a positive integer greater than or equal to 1;

The sixth generating unit is used to generate N first anonymous identities of the aircraft according to the aircraft registration number, the session key and the N identity vectors;

The forming unit is used to form an anonymous identity database based on the N first anonymous identities.

In some possible embodiments, the conversation module 750 includes:

a seventh generating unit, configured to generate a third message based on the anonymous identity database;

a first sending unit, configured to send a third message to the ground station;

The first receiving unit is configured to receive the fourth message sent by the ground station.

In some possible embodiments, the seventh generating unit includes:

generating and calculating subunits for generating the first plaintext and the first message sequence number, and calculating the first hash value of the first plaintext and the first message sequence number;

a first calculation subunit, configured to calculate the second initial vector of the third message according to the first message sequence number and the first initial vector;

a first generating subunit, configured to generate a second ciphertext through the session key according to the first plaintext, the first hash value and the second initial vector;

A selection subunit, used to select a third anonymous identity in the anonymous identity database through a random number algorithm;

The replacement subunit is used for replacing the aircraft registration number in the third message with the third anonymous identity, and after filling the segment in the third message into the second ciphertext, then sending the third message to the ground station.

In some possible embodiments, the first receiving unit includes:

a first obtaining subunit, used for obtaining the fourth anonymous identity in the fourth message;

a search sub-unit for searching the fourth anonymous identity in the anonymous identity database;

a query subunit, configured to query the first initial vector and the session key corresponding to the fourth anonymous identity when the fourth anonymous identity is found in the anonymous identity database;

a second acquisition subunit, used for acquiring the second message sequence number in the fourth message;

a second calculation subunit, configured to calculate the third initial vector of the fourth message according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number;

The third obtaining subunit is used to obtain the third ciphertext in the fourth message, decrypt the third ciphertext according to the session key and the third initial vector, and obtain the second plaintext and the second hash value;

a third calculation subunit, configured to calculate the third hash value of the second plaintext and the second message sequence number;

a verification sub-unit for verifying whether the third hash value is equal to the second hash value;

The first discarding subunit is configured to process the second plaintext when the third hash value is equal to the second hash value, and discard the second plaintext when the third hash value is not equal to the second hash value. Four messages.

In some possible embodiments, the first receiving unit further includes:

The second discarding subunit is configured to discard the fourth message when the fourth anonymous identity cannot be found in the anonymous identity database.

In some possible embodiments, the civil aviation ACARS ground-air data link anonymous security session device includes:

The public key acquisition module is used to acquire the identity information of the ground station and the public key corresponding to the identity information of the ground station through the certification center.

It should be noted that the foregoing explanations of the embodiment of the civil aviation ACARS ground-air data link anonymous security session method are also applicable to the civil aviation ACARS ground-air data link anonymous security session device of this embodiment, which will not be repeated here.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless expressly and specifically defined otherwise.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other.

Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limitations to the present application. Embodiments are subject to variations, modifications, substitutions and variations.

Claims (10)

1. a civil aviation ACARS ground-air data link anonymous security session method, applied to aircraft, is characterized in that, comprises: Receive the ground station identity message broadcast by the ground station; Sending a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, wherein the first message includes a first initial vector; receiving a second message sent by the ground station; Verifying the second message, in the case of passing the verification, generating an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous identities, and N is a positive integer greater than or equal to 1; A session is conducted with the ground station based on the anonymous identity repository. 2. The method according to claim 1, wherein the sending the first message to the ground station through an asymmetric key mechanism based on the ground station identity information comprises: Determine the public key of the ground station according to the identity information of the ground station; generating the first initial vector, the session key, and recording the timestamp of the current time; generating a second anonymous identity of the aircraft through the public key of the ground station according to the aircraft registration number and the session key; generating a first signature through the private key of the aircraft according to the first initial vector, the session key, the timestamp and the aircraft registration number; generating a first ciphertext through the public key of the ground station according to the first initial vector, the session key, the timestamp and the first signature; Replacing the aircraft registration number in the first message with the second anonymous identity of the aircraft, and after filling the message segment in the first message with the first ciphertext, send a message to the ground The station sends the first message. 3. method according to claim 2, is characterized in that, described second message of described verification, comprises: Obtain a second signature through the second message; The second signature is verified by the public key of the ground station. 4. The method according to claim 3, wherein, when the verification is passed, generating an anonymous identity library according to the first initial vector, comprising: Add one to the first initial vector in turn to generate N identity vectors, where N is a positive integer greater than or equal to 1; generating the N first anonymous identities of the aircraft according to the aircraft registration number, the session key and the N identity vectors; The anonymous identity database is formed based on the N first anonymous identities. 5. The method according to claim 4, wherein the conducting a session with the ground station based on the anonymous identity database comprises: generating a third message based on the anonymous identity repository; sending the third message to the ground station; A fourth message sent by the ground station is received. 6. The method according to claim 5, wherein the generating a third message based on the anonymous identity database comprises: generating a first plaintext and a first message sequence number, and calculating a first hash value of the first plaintext and the first message sequence number; Calculate a second initial vector of the third message according to the first message sequence number and the first initial vector; generating a second ciphertext by using the session key according to the first plaintext, the first hash value and the second initial vector; Selecting a third anonymous identity through a random number algorithm in the anonymous identity database; Replacing the aircraft registration number in the third message with a third anonymous identity, and after filling the segment in the third message with the second ciphertext, sending the ground station the Third message. 7. The method according to claim 5, wherein the receiving the fourth message sent by the ground station comprises: obtaining a fourth anonymous identity in the fourth message; looking up the fourth anonymous identity in the anonymous identity repository; In the case that the fourth anonymous identity is found in the anonymous identity database, query the first initial vector and the session key corresponding to the fourth anonymous identity; obtaining the sequence number of the second message in the fourth message; Calculate the third initial vector of the fourth message according to the first initial vector corresponding to the fourth anonymous identity and the second message sequence number; Obtain the third ciphertext in the fourth message, decrypt the third ciphertext according to the session key and the third initial vector, and obtain the second plaintext and the second hash value; calculating a third hash value of the second plaintext and the second message sequence number; verifying that the third hash value is equal to the second hash value; In the case that the third hash value is equal to the second hash value, the second plaintext is processed, and in the case that the third hash value is not equal to the second hash value, The fourth message is discarded. 8. The method according to claim 7, wherein after searching the fourth anonymous identity in the anonymous identity database, the method further comprises: If the fourth anonymous identity cannot be found in the anonymous identity database, the fourth message is discarded. 9. The method according to claim 2, wherein before determining the public key of the ground station according to the identity information of the ground station, the method comprises: The identity information of the ground station and the public key corresponding to the identity information of the ground station are obtained through the certification center. 10. A civil aviation ACARS ground-air data link anonymous security session device, applied to an aircraft, characterized in that, comprising: a first receiving module, configured to receive the ground station identity message broadcast by the ground station; a sending module, configured to send a first message to the ground station through an asymmetric key mechanism based on the ground station identity message, wherein the first message includes a first initial vector; a second receiving module, configured to receive the second message sent by the ground station; A verification module, configured to verify the second message, and in the case of passing the verification, generate an anonymous identity database according to the first initial vector, wherein the anonymous identity database includes N first anonymous identities, and N is greater than or equal to a positive integer of 1; A session module, configured to conduct a session with the ground station based on the anonymous identity database.

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