GB/T 44778-2024Technical requirements and test methods for cybersecurity of vehicle diagnostic interfaces (English PDF)

5.1 General requirements

5.1.1 Identity authentication and permission control Meet the following requirements.

a) Conduct the test according to

6.1.1 a). The diagnostic access authentication unit should support opening different access rights for the diagnostic access unit;

b) Conduct the test in accordance with

6.1.1 b). The diagnostic access authentication unit should support identity authentication or permission control for the diagnostic access unit;

c) Conduct the test in accordance with

6.1.1 c). The diagnostic access unit should support identity authentication of the diagnostic access authentication unit.

5.1.2 Authentication algorithm

5.1.2.1 Technical requirements for authentication based on symmetric encryption algorithms Meet the following requirements.

a) Conduct the test in accordance with

6.1.2.1 a). Use a symmetric encryption algorithm for identity authentication. The encryption algorithm should be SM4, AES128, or an algorithm of equivalent strength or higher.

b) Conduct the test in accordance with

6.1.2.1 b). Use a symmetric encryption algorithm for identity authentication. The symmetric key should have a way to update it.

5.1.2.2 Authentication technology requirements based on asymmetric encryption algorithms Conduct the test in accordance with 6.1.2.2.Use an asymmetric encryption algorithm for identity authentication. The encryption algorithm should be SM2, ECC256, or an algorithm of equivalent strength or higher, or an RSA algorithm with a data length of at least 2048 bits.

a) Conduct the test in accordance with

6.3.2.2 a). Access rights to diagnostic services should be divided according to different diagnostic users (e.g., development, production, after-sales, supplier parts development, etc.). Diagnostic services should be grouped by secure access to achieve separation of permissions for different diagnostic users;

b) Conduct the test in accordance with

6.3.2.2 b). The authority setting of the diagnostic user shall follow the principle of minimization defined by the vehicle manufacturer.

5.4 Physical connection security requirements

5.4.1 Physical connection requirements for the diagnostic connector Meet the following requirements.

a) Conduct the test in accordance with

6.4.1 a). The on-board diagnostic connector should not be connected to other communication buses not used for diagnosis;

b) Conduct the test in accordance with

6.4.1 b). For non-communication hard lines connected to the on-board diagnostic connector, only the following functions should be supported. 1) Power supply for the diagnostic access unit; 2) Hard-wired connections required by regulations and standards (e.g., Ethernet activation cable, recovery detonation cable, etc.).

5.4.2 Communication bus requirements for diagnostic connectors Conduct the test in accordance with 6.4.2.The communication bus connected to the on- board diagnostic connector should only be connected to the electronic control unit that performs the functions of diagnostic access authentication unit.

6.1 Test methods for diagnostic interface information security

6.1.1 Test methods for identity authentication and authority control Carry out the test in the following order.

a) Use the test tool to initiate identity authentication or access requests with different permissions to the diagnostic access authentication unit. Check whether the diagnostic access authentication unit passes the request with permission. Reject the request without permission;

b) Initiate an access request to the diagnostic access authentication unit through the test tool. Check whether the diagnostic access authentication unit performs identity authentication or permission control on the requesting device;

c) Initiate an access request to the test tool through the diagnostic access unit. Check whether the diagnostic access unit authenticates the test tool.

6.1.2 Test methods for identity authentication algorithms

6.1.2.1 Test method for authentication based on symmetric encryption algorithm Carry out the test in the following order.

a) For authentication using symmetric encryption algorithms, the system monitors and analyzes the authentication message data between the diagnostic access unit and the diagnostic access authentication unit to positively check whether SM4, AES128, or an encryption algorithm of equivalent strength or higher is used;

b) Check whether the symmetric key used for identity authentication can be updated according to the provided key security management policy or usage scenario requirements.

6.1.2.2 Test method for authentication based on asymmetric encryption algorithm For identity authentication using asymmetric encryption algorithms, the system monitors and analyzes the authentication message data between the diagnostic access unit and the diagnostic access authentication unit to positively check whether SM2, ECC256 or an algorithm of the same level or above is used, or select the RSA algorithm with a data length of not less than 2048 bits.

6.1.2.3 Test method for summarization algorithm By monitoring and parsing the identity authentication message data the diagnostic access unit and the diagnostic access authentication unit, positively check whether the digest algorithm uses SM3, SHA256 or an algorithm of the same level or above.

6.2 Test methods for information security of diagnostic access units

6.2.1 Test methods for secure storage Use the test tool to try to modify or delete the symmetric key and asymmetric algorithm private key information used for authentication stored on the diagnostic access unit to check whether they can be tampered with.

6.2.2 Test methods for data usage Carry out the test in the following order.

a) Use different user identities to access the symmetric key and asymmetric algorithm private key used for authentication stored in the diagnostic access unit. Check that only users with access rights can successfully access the key, and other users cannot use or access the key;

b) Monitor and analyze the message data sent by the diagnostic access unit. Check whether the data contains information related to symmetric keys and asymmetric algorithm private keys for identity authentication;

c) By checking the diagnostic access unit of the non-vehicle electronic control unit, it is detected whether it has access control methods (for example. account login, dynamic acquisition of operation permissions, etc.).

6.2.3 Test method for key information destroy For diagnostic access units outside of the vehicle's electronic control unit, verify that they have a key destruction mechanism (e.g., resetting the non-volatile memory area to FF or 00) to destroy authentication-related data. If a session key is used, verify that the session key is cleared when the diagnostic interface switches to the locked state and when the controller boots up.

6.3.1 Test methods for controller information security

6.3.1.1 Test methods for secure storage Carry out the test in the following order.

a) Review information security design-related documents. Check whether the diagnostic access authentication unit uses a hardware security storage mechanism to store the symmetric key and asymmetric algorithm private key information used for identity authentication;

b) Use the test tool to try to access, modify or delete the identity information used for authentication stored at the diagnostic access authentication unit to check whether it is stored securely.

6.3.1.2 Test methods for authority control Carry out the test in the following order.

a) Use the test tool to simulate different diagnostic access units sending diagnostic service requests to the diagnostic access authentication unit. Check whether the diagnostic access authentication unit sends a positive response to requests within its authorized scope and a denial of access to requests outside its authorized scope;