Key management method and vehicle

Abstract

The invention discloses a key management method and a vehicle. The key management method comprises the following steps: a key management master node performs security verification on a key management slave node in response to key seed acquisition request information sent by the key management slave node, and sends key seed acquisition response information comprising a key seed to the key management slave node under the condition that the security verification is passed, a key seed is generated based on a key random number. The key management slave node responds to the received key seed to obtain the response information and obtain the key seed, and the key management slave node generates the key based on the key seed under the condition that the key use requirement exists, so that the risk that the key is cracked can be effectively reduced, and the key security is improved. Furthermore, the key seed is generated by the key management main node based on the key random number, so that the key seed information generated by the key management main node can be effectively ensured not to be predicted, the risk that the key is cracked is further reduced, and the key security is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of key management, and in particular to a key management method and a vehicle. Background Art

[0002] In order to prevent and mitigate network attacks, more and more information security measures are being applied in network protection. Currently, security measures are usually implemented based on cryptographic technology, and most cryptographic technologies rely on keys. There are many usage scenarios for keys, but there is currently no perfect and unified key management solution. Currently, keys are pre-configured, and pre-configured keys are fixed, resulting in a high risk of key cracking. Therefore, how to achieve perfect and unified key security management and reduce the risk of keys being easily cracked and obtained is an urgent problem to be solved. Summary of the invention

[0003] The purpose of this application is to solve the problem that keys are easily cracked and obtained. To solve the above technical problems, the implementation of this application discloses a key management method and a vehicle.

[0004] In a first aspect, an embodiment of the present application provides a key management method, which is applied to a key management system, wherein the key management system includes a key management master node and multiple key management slave nodes; the key management method includes:

[0005] The key management master node performs security verification on the key management slave node in response to receiving the key seed acquisition request information sent by the key management slave node, and sends key seed acquisition response information to the key management slave node if the security verification passes, the key seed acquisition response information includes key seed information, the key seed information includes a key seed, and the key seed is generated by the key management master node based on a key random number;

[0006] The key management slave node obtains a key seed in response to receiving a key seed acquisition response message, obtains a key seed according to the key seed acquisition response message, and generates a key according to the key seed for business encryption processing when there is a key usage requirement.

[0007] When the key management method is used to manage the key, the key management master node generates a key seed based on the received key seed acquisition request information and sends the key seed to the key management slave node. When there is a demand for key use, the key management slave node generates a key based on the key seed. In this key management method, the key is generated based on the key seed, which can effectively reduce the risk of the key stored in the firmware being cracked and improve the security of the key. Furthermore, the key seed is generated by the key management master node based on the key random number, which can effectively ensure that the key seed information generated by the key management master node cannot be predicted, further reducing the risk of the key being cracked and improving the security of the key.

[0008] In a possible implementation of the key management method of the present application, the key management method further includes:

[0009] When receiving the key seed distribution notification information sent by the key management master node, the key management slave node sends a key seed acquisition request information to the key management master node.

[0010] When the key management method is used to manage the key, the key management slave node generates a key seed acquisition request message based on the key seed distribution notification message received from the key management master node. The key seed acquisition request message obtained based on the method corresponds to the key seed acquisition request message generated by the key management slave node, so that the key seed acquisition request message has a corresponding relationship with the key management slave node, thereby effectively ensuring the accuracy of the security verification of the key management slave node based on the key seed acquisition request message.

[0011] In a possible implementation of the key management method of the present application, the key management method further includes:

[0012] The key management master node generates key seed distribution notification information in response to receiving the key seed distribution instruction information sent by the diagnostic tool; or,

[0013] The key management master node generates key seed distribution notification information according to a preset key seed distribution cycle.

[0014] When the key management method is used to manage the key, when the diagnostic tool sends the key seed distribution instruction information to the key management master node, the key management master node generates the key seed acquisition request information. That is, the user can update the key seed based on the diagnostic requirements, so that the key seed can be regenerated after the old key seed is obtained by the attacker, thereby effectively avoiding the risk of affecting the operation of the electronic equipment involved in the key management system after the key seed is obtained by the attacker.

[0015] Furthermore, the key management master node can generate key seed acquisition request information according to a preset key seed distribution cycle. Based on the method for generating key seed acquisition request information, key seed distribution notification information can be regularly updated based on the key seed distribution cycle, that is, key seeds can be regularly generated and updated. Periodic updating of key seeds can regenerate new key seeds after the old key seeds are obtained by attackers, effectively avoiding the risk of affecting the operation of electronic devices involved in the key management system after the key seeds are obtained by attackers.

[0016] In a possible implementation of the key management method of the present application, the key seed distribution period is determined according to the power-on period of the electronic device involved in the key management system.

[0017] When the key management method is used to manage keys, the key seed distribution period can be determined based on the power-on period of the electronic device corresponding to the key management system. Based on the method, the key seed distribution period can be determined by setting a certain relationship between the power-on period and the key seed distribution period, so as to facilitate the subsequent management of the currently generated key seed and the key seed currently used to generate the key.

[0018] In a possible implementation of the key management method of the present application, the key seed acquisition request information includes identification information and identity token information of the key management slave node, and the key management master node performs security verification on the key management slave node, including:

[0019] The key management master node parses the identification information and identity token information of the key management slave node from the key seed acquisition request information, and performs security verification on the key management slave node based on the identification information and identity token information of the key management slave node and the key management slave node registration information. The key management slave node registration information includes the identification information, identity token information and validity information of the identity token information of the key management slave node registered with the key management master node. If the identification information and identity token information of the key management slave node exist in the key management slave node registration information and the identity token information is valid, the security verification result of the key management slave node is that the security verification passed. If the identification information and identity token information of the key management slave node do not exist in the key management slave node registration information, or the identity token information is invalid, the security verification result of the key management slave node is that the security verification failed.

[0020] When the key management method is used to manage keys, before sending a key seed acquisition response message to the key management slave node, the key management master node security verifies the identity of the key management slave node. When the security verification of the key management slave node is passed, the key management master node sends a key seed acquisition response message to the slave node. Setting the key management slave node identity authentication in the key management method can effectively ensure the accuracy of the identity of each node and further prevent the risk of the key seed being obtained by an attacker.

[0021] In a possible implementation of the key management method of the present application, the key management slave node registration information is generated in the following manner:

[0022] The key management master node sends node identity registration notification information to the key management slave node;

[0023] In response to receiving the node identity registration notification information, the key management slave node sends identity registration request information to the key management master node, where the identity registration request information includes identification information of the key management slave node;

[0024] The key management master node generates identity token information and identity key information of the key management slave node in response to receiving the identity registration request information, obtains the key management slave node registration information, and generates identity registration response information and sends it to the key management slave node, the identity registration response information includes the identity token information and identity key information of the key management slave node, and the identity key information is used to encrypt and decrypt the identity token information and the key seed information;

[0025] In response to receiving the identity registration response information, the key management slave node parses the identity token information and identity key information of the key management slave node from the identity registration response information for storage, and sends the identity registration response parsing result information to the key management master node;

[0026] The key management master node obtains the identity registration response parsing result in response to receiving the identity registration response parsing result information.

[0027] When the above-mentioned key management method is used to manage keys, the identity registration of the key management slave node is completed before the key management master node generates the key seed distribution information. The accuracy of the identity of the key management slave node can be determined based on the identity information of the registered key management slave node in the subsequent key seed distribution process, thereby ensuring the accuracy of the key seed distribution and preventing the key seed from being obtained by attackers. When the key management slave node performs identity registration, an identity key corresponding to the key management slave node is generated, so that the key seed can be encrypted based on the identity key when the key seed is subsequently generated, thereby effectively preventing the key seed from being obtained by attackers.

[0028] In a possible implementation of the key management method of the present application, the key management master node sends node identity registration notification information to the key management slave node, including:

[0029] The key management master node sends node identity registration notification information to the key management slave node in response to receiving the node identity registration instruction information sent by the diagnostic tool;

[0030] The method also includes:

[0031] The key management master node generates identity registration result response information based on the identity registration response parsing result, and sends the identity registration result response information to the diagnostic tool;

[0032] The diagnostic tool obtains the identity registration result in response to receiving the identity registration result response information.

[0033] When the above-mentioned key management method is used to manage keys, the diagnostic tool sends node identity registration information, so that the key management master node generates identity information of the key management slave node, and the key management master node sends identity registration result response information to the diagnostic tool, so that the diagnostic tool determines that the identity registration of the key management slave node has been completed, so as to facilitate the subsequent triggering of key seed acquisition information and generate key seeds.

[0034] In a possible implementation of the key management method of the present application, the node identity registration instruction information includes the node identity token validity period information, and the key management method further includes:

[0035] The key management master node manages the validity period of the identity token of the key management slave node based on the node identity token validity period information.

[0036] When the key management method is used to manage the key, the node identity token validity period information is set in the node identity registration instruction information. Based on the node identity token validity period, the validity of the current node identity token can be determined, and based on the validity, it can be determined whether the received identity token is correct, thereby ensuring the security of distributing the key seed and effectively preventing the risk of the key seed being obtained.

[0037] In a possible implementation of the key management method of the present application, the node identity registration instruction information includes key seed distribution cycle information, and the key management method further includes:

[0038] The key management master node manages the key seed distribution time based on the key seed distribution cycle information.

[0039] When the key management method is used to manage keys, the key management master node distributes keys to the key management slave nodes based on the key seed distribution cycle, which can manage key distribution and ensure the orderliness of key distribution.

[0040] In a possible implementation of the key management method of the present application, the identification information is the name and / or serial number information of the electronic device involved in the key management slave node.

[0041] When the above-mentioned key management method is used to manage keys, the name and / or serial number information of the electronic device involved in the key management slave node is set in the identification information. The identity information of the key management slave node can be determined based on the name and / or serial number of the electronic device, thereby effectively ensuring the security of key seed transmission.

[0042] In a possible implementation of the key management method of the present application, the key management slave node generates a key according to a key seed when there is a key usage requirement, including:

[0043] When there is a demand for key use, the key management slave node generates a key based on a key seed generated in the last power-on cycle of the electronic device involved in the key management system.

[0044] When the key management method is used to manage keys, the key is generated based on the key seed generated in the previous power-on cycle, which can effectively prevent the risk of being unable to generate keys due to the lack of key seeds in the key management slave node when the key is needed during the key seed generation process.

[0045] In a possible implementation of the key management method of the present application, the key management method further includes:

[0046] The key management slave node stores the generated key in the memory of the key management slave node.

[0047] When the key management method is used to manage the key, the key is stored in the memory of the key management slave node, that is, the key is not stored in the firmware, which can effectively prevent the risk of the key being obtained by an attacker.

[0048] In a possible implementation of the key management method of the present application, the key management method further includes:

[0049] The key management slave node generates an old key based on an old key seed, decrypts the target data, generates a new key based on a new key seed, encrypts the target data, and deletes the old key seed and the old key.

[0050] When the key management method is used to manage keys, after a new key seed is generated, the old key seed is deleted, which can effectively prevent the problem of calling errors caused by too many key seeds when calling key seeds.

[0051] In a possible implementation manner of the key management method of the present application, the key management method further includes, the key management slave node destroying the key seed in any of the following situations:

[0052] Get a new key seed;

[0053] Use up the key seed;

[0054] Receive the key seed destruction instruction set by the system predefined settings.

[0055] When the key management method is used to manage keys, the old key seed is destroyed when a new key seed is obtained, a used key seed is obtained, or a key seed destruction instruction is received, which can effectively prevent the problem of key seed calling errors when calling key seeds.

[0056] In a possible implementation of the key management method of the present application, the key management system further includes a hardware security module, the hardware security module includes a random number generator, and the key random number is generated by the random number generator and sent to the key management master node.

[0057] When the above-mentioned key management method is used to manage keys, a hardware security module is provided in the key management master node, and a random number generator is provided in the hardware security module. A key random number is generated based on the random number generator, and a key seed is generated based on the key random number. This can effectively ensure that the key seed information generated by the key management master node cannot be predicted, further reducing the risk of the key being cracked.

[0058] In a possible implementation of the key management method of the present application, the key management method further includes:

[0059] The information transmitted between the key management master node and the key management slave node is encrypted and transmitted based on the preset key.

[0060] When the above-mentioned key management method is used to manage keys, when information is transmitted between the key management master node and the key management slave node, the transmitted information is encrypted based on the preset key, which can effectively ensure the security of information transmission and further ensure the security of key seed generation and transmission process.

[0061] In a possible implementation of the key management method of the present application, the electronic devices involved in the key management master node and the key management slave node are electronic control units.

[0062] In a second aspect, another embodiment of the present application discloses a vehicle, the vehicle includes a key management system, the key management system includes a key management master node and multiple key management slave nodes, the key management master node and the key management slave nodes interact to implement a key management method as described in any one of the above embodiments.

[0063] Another embodiment of the present application provides a vehicle provided with a key management system, and information exchange can be performed in the key management system. Keys are generated and managed based on the key management method of any of the above-mentioned embodiments, thereby effectively preventing the risk of keys in the vehicle being obtained by attackers and effectively ensuring the safe use of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 A schematic diagram of a key management method provided for an implementation of the present application;

[0065] Figure 2 A flowchart of another key management method provided for an embodiment of the present application;

[0066] Figure 3 A flowchart of another key management method provided in an embodiment of the present application;

[0067] Figure 4 A schematic diagram of a process for generating key management slave node registration information in a key management method provided in an embodiment of the present application;

[0068] Figure 5 A schematic diagram of another process for generating key management slave node registration information in the key management method provided in an embodiment of the present application;

[0069] Figure 6 A schematic diagram of the structure of a key management system provided by another embodiment of the present application;

[0070] Figure 7 A schematic structural diagram of a vehicle provided in yet another embodiment of the present application. DETAILED DESCRIPTION

[0071] In the existing network security protection, in order to prevent and mitigate network attacks, information in the network can be protected based on cryptographic technology. However, the implementation of cryptographic technology depends on keys. Keys are used in many scenarios, but there is no perfect management method for key management, resulting in a high risk of key cracking.

[0072] For example, take the risk of the key in a vehicle being cracked as an example.

[0073] In a vehicle, when the vehicle is off the production line, after the diagnostic tool diagnoses it, the key management system in the vehicle generates the key used in the operation of the vehicle. In addition, the key used in the operation of the vehicle is fixed throughout the life cycle of the vehicle, that is, the key does not support update. This easily leads to a high risk of the key being cracked during the use of the vehicle.

[0074] Furthermore, the keys generated in the key management system are stored in the hard disk, and the keys may even be stored in plain text in the hard disk, which further leads to a greater risk of the keys being obtained by attackers.

[0075] Based on the above problems, the present application provides a key management method and a vehicle. In the key management method, the key management slave node generates a key based on a key seed, and the key seed is generated by the key management master node based on a key random number, thereby effectively reducing the risk of the key being cracked. In addition, the key seed is stored in the key management master node and the key management slave node and the key seed is periodically updated, further reducing the risk of the key being cracked.

[0076] refer to Figure 1 , Figure 1 A flowchart of a key management method provided for an embodiment of the present application. In a first aspect, an embodiment of the present application provides a key management method, which is applied to a key management system, the key management system comprising a key management master node and multiple key management slave nodes; the key management method comprises:

[0077] Step S1: The key management master node performs security verification on the key management slave node in response to receiving key seed acquisition request information sent by the key management slave node.

[0078] Step S2: When the security verification passes, the key management master node sends a key seed acquisition response message to the key management slave node. The key seed acquisition response message includes key seed information. The key seed information includes a key seed. The key seed is generated by the key management master node based on a key random number.

[0079] Step S3: The key management slave node obtains a key seed in response to receiving the key seed acquisition response information, and obtains the key seed according to the key seed acquisition response information.

[0080] Step S4: When there is a need to use a key, the key management slave node generates a key based on the key seed for use in business encryption processing.

[0081] When the key management method is used to generate and manage keys, the key management master node generates a key seed based on the received key seed acquisition request and sends the key seed to the key management slave node. When there is a demand for key use, the key management slave node generates a key based on the key seed. In the key management method, the key management slave node generates a key based on the key seed, thereby effectively reducing the risk of the key being cracked. Furthermore, the key seed is generated by the key management master node based on the key random number, which can effectively ensure that the key seed information generated by the key management master node cannot be predicted, further reducing the risk of the key being cracked.

[0082] refer to Figure 1 In a possible implementation of the key management method of the present application, the specific method of step S1 in the key management method includes: the key management master node receives the key seed acquisition request information sent by the key management slave node; the key management master node verifies the security of the key management slave node based on the key seed acquisition request information. If the security verification of the key management slave node passes, step S2 is executed; if the security verification of the key management slave node fails, the subsequent steps are stopped.

[0083] The specific method of step S2 includes: the key management master node generates a key seed acquisition response message, encrypts the key seed acquisition response message based on a pre-stored identity key of the key management slave node, and sends the encrypted message to the key management slave node.

[0084] Furthermore, the key seed acquisition response information includes: key seed information, and the key seed information includes: key seed and key seed batch number. By setting the key seed batch number in the key seed information, the corresponding key seed can be determined based on the key seed batch number, and by setting the key seed batch number, the target key seed can be quickly determined based on the key seed batch number.

[0085] The specific method of step S3 includes: the key management slave node receives the key seed to obtain the response information; the key management slave node decrypts the key seed based on the pre-stored identity key of the key management slave node to obtain the response information and analyzes it to obtain the key seed.

[0086] The specific method of step S4 includes: the key management slave node responds to the received key acquisition information, generates a corresponding key based on the key seed and the key generation rule, encrypts the business based on the key, and the key is a key used for cryptographic operations on business function data.

[0087] Furthermore, in a possible implementation of the key management method of the present application, the key seed is generated based on a key random number, which can ensure that the key seed generated each time is different and the key seed generated each time is unpredictable, thereby effectively ensuring that the information of the key seed cannot be predicted by an attacker, reducing the risk of the key seed being cracked.

[0088] In addition, in the key management method of the present application, the number of key management slave nodes in the key management system can be multiple, and multiple key management slave nodes can generate corresponding key seeds at the same time.

[0089] refer to Figure 2 , Figure 2 A flowchart of another key management method provided for an implementation of the present application. In a possible implementation of the key management method of the present application, the key management method further includes:

[0090] Step S0: upon receiving the key seed distribution notification information sent by the key management master node, the key management slave node sends a key seed acquisition request information to the key management master node.

[0091] refer to Figure 2 In a possible implementation of the key management method of the present application, the key management master node performs security verification on the key management slave node based on the received key seed acquisition request information. The specific method for the key management slave node to generate and send the key seed acquisition request information to the key management master node includes: the key management slave node receives the key seed distribution notification information sent by the key management master node. The key management slave node calls the pre-stored identifier of the key management slave node and the identity token of the key management slave node based on the key seed distribution notification information. The key management slave node encrypts the identifier of the key management slave node and the identity token of the key management slave node based on the pre-stored identity key to generate the key seed acquisition request information, and sends the key seed acquisition request information to the key management master node.

[0092] In a possible implementation of the key management method of the present application, the key seed acquisition request information includes identification information and identity token information of the key management slave node, and the key management master node performs security verification on the key management slave node, including:

[0093] The key management master node parses the identification information and identity token information of the key management slave node from the key seed acquisition request information, and performs security verification on the key management slave node based on the identification information and identity token information of the key management slave node and the key management slave node registration information. The key management slave node registration information includes the identification information, identity token information and validity information of the identity token information of the key management slave node registered with the key management master node. If the identification information and identity token information of the key management slave node exist in the key management slave node registration information and the identity token information is valid, the security verification result of the key management slave node is that the security verification passed. If the identification information and identity token information of the key management slave node do not exist in the key management slave node registration information, or the identity token information is invalid, the security verification result of the key management slave node is that the security verification failed.

[0094] In the above-mentioned key management method, the key management master node needs to perform security verification on the key management slave node before sending the key seed acquisition response information to the key management slave node. In a possible implementation of the key management method of the present application, the key management master node can perform security verification on the key management slave node based on the identification information and identity token information of the key management slave node in the key seed acquisition request information and the key management slave node registration information pre-stored in the key management master node.

[0095] Furthermore, the specific method for the key management master node to perform security verification on the key management slave node includes: when the key management master node receives the key seed acquisition request information, the key management master node decrypts the received key seed acquisition request information based on the pre-stored identity key of the key management slave node. The key management master node decrypts and obtains the identification information and identity token information of the key management slave node, and compares the decrypted identification information and identity token information of the key management slave node with the identification information and identity token information of the key management slave node in the pre-stored key management slave node registration information.

[0096] Furthermore, if the identification information and identity token information of the key management slave node are in the registration list of the key management master node, it proves that the key management slave node is a key management slave node that exchanges information with the key management master node, and if the identity token is valid, it proves that the current key management master node and the corresponding key management slave node exchange information. The key management master node generates a key seed corresponding to the key management slave node and sends the key seed to the key management slave node.

[0097] Furthermore, if the identification information and identity token information of the key management slave node are not in the registration list of the key management master node, it proves that the key management slave node is not the key management slave node that exchanges information with the key management master node, and the key management master node will not generate the key seed corresponding to the key management slave node. If the identification information and identity token information of the key management slave node are in the registration list of the key management master node, but the identity token of the key management slave node is invalid, the key management master node sends an identity registration information notification to the key management slave node, and the key management slave node re-registers the identity information.

[0098] refer to Figure 3 , Figure 3 A flowchart of another key management method provided for an implementation of the present application. In a possible implementation of the key management method of the present application, the key management method further includes:

[0099] Step S01: the key management master node generates key seed distribution notification information in response to receiving key seed distribution instruction information sent by the diagnostic tool; or,

[0100] Step S02: The key management master node generates key seed distribution notification information according to a preset key seed distribution cycle.

[0101] refer to Figure 3In one possible implementation of the key management method of the present application, the key management master node automatically generates key seed distribution notification information based on the key seed distribution instruction information received from the diagnostic tool or the key management master node based on a preset key seed distribution cycle, and sends it to the key management master node, so that the key management master node executes subsequent steps to generate key seeds.

[0102] Furthermore, when the key management master node automatically generates key seed distribution notification information based on a preset key seed distribution cycle, the key management master node generates corresponding key seed distribution notification information at a node of the key seed distribution cycle based on the preset key seed distribution cycle, and the key management master node executes subsequent steps based on the key seed distribution notification information to generate a key seed corresponding to the key seed distribution cycle, thereby updating the key seed.

[0103] Further, the key management master node can trigger the generation of the key seed distribution instruction based on the key seed distribution instruction information sent by the diagnostic tool when the electronic device involved in the key management system is prepared, or based on the needs of the administrator corresponding to the electronic device involved in the key management system, the diagnostic tool triggers the generation of the key seed distribution instruction. The administrator can remotely trigger the generation of the key seed distribution instruction through the diagnostic tool based on actual needs, and the administrator can remotely trigger the generation of the key seed distribution instruction multiple times based on actual needs to update the key seed.

[0104] refer to Figure 3 Further, in a possible implementation of the key management method of the present application, before step S4, the key management method further includes: step S31: the key management slave node sends key seed acquisition result information to the key management master node; step S32: the key management master node obtains the key seed acquisition result in response to receiving the key seed acquisition result information; step S33: the key management master node generates key seed acquisition situation information based on the key seed acquisition result in response to receiving the key seed acquisition situation determination information sent by the diagnostic tool, and sends the key seed acquisition situation information to the diagnostic tool; step S34: the diagnostic tool obtains the key seed acquisition situation in response to receiving the key seed acquisition situation information. Based on the above steps, the diagnostic tool determines that the key management slave node obtains the key seed to determine that the key management system can generate the key so that the electronic equipment involved in the key management system can operate.

[0105] Based on the above, it can be known that in the key management method of the present application, the key seed can be automatically updated regularly based on the preset key seed distribution cycle, which can effectively reduce the risk of the key seed being cracked, thereby reducing the risk of the key being cracked.

[0106] In a possible implementation of the key management method of the present application, the key management slave node generates a key according to a key seed when there is a key usage requirement, including:

[0107] When there is a demand for key use, the key management slave node generates a key based on a key seed generated in the last power-on cycle of the electronic device to which the key management system is applied.

[0108] In a possible implementation of the key management method of the present application, the key seed distribution period is determined according to the power-on period of the electronic device involved in the key management system.

[0109] In a possible implementation of the key management method of the present application, the key seed used to generate the key in the current power-on cycle is the key seed generated in the previous power-on cycle. In the key management system, the generation of the key seed is based on the key seed distribution cycle or the triggering of the diagnostic tool to generate the key seed distribution notification information, thereby triggering the subsequent steps to generate, and because the key seed distribution cycle is fixed, the power-on node of the electronic device corresponding to the key management system is uncertain, in order to prevent the key seed from being updated when the node is powered on, there is no key seed that can generate the key, so in the key management method, the currently required key is generated according to the key seed generated in the previous power-on cycle of the electronic device to which the key management system is applied.

[0110] Furthermore, in a possible implementation of the key management method of the present application, a relationship is set between the distribution period of the key seed and the power-on period of the electronic device, so that the distribution period of the key seed can be determined based on the power-on period of the electronic device involved in the key management system, thereby facilitating the determination of the key seed corresponding to be used within the power-on period of the electronic device.

[0111] Furthermore, the key seed distribution cycle can be set to one power-on cycle corresponding to one key seed distribution cycle or set to one week corresponding to one key seed distribution cycle or one month corresponding to one key seed distribution cycle in accordance with the actual usage scenario. The specific key seed distribution cycle can be set by the administrator based on the specific usage scenario of the electronic device involved in the key management system.

[0112] refer to Figure 4 , Figure 4 A schematic diagram of a process for generating key management slave node registration information in a key management method provided in an embodiment of the present application. In a possible implementation of the key management method of the present application, the key management slave node registration information is generated in the following manner:

[0113] Step S11: the key management master node sends node identity registration notification information to the key management slave node.

[0114] Step S12: In response to receiving the node identity registration notification information, the key management slave node sends identity registration request information to the key management master node, where the identity registration request information includes the identification information of the key management slave node.

[0115] Step S13: In response to receiving the identity registration request information, the key management master node generates the identity token information and identity key information of the key management slave node, and obtains the key management slave node registration information.

[0116] Step S14: the key management master node generates identity registration response information and sends it to the key management slave node. The identity registration response information includes the identity token information and identity key information of the key management slave node. The identity key information is used to encrypt and decrypt the identity token information and key seed information.

[0117] Step S15: In response to receiving the identity registration response information, the key management slave node parses the identity token information and identity key information of the key management slave node from the identity registration response information and stores them.

[0118] Step S16: The key management slave node sends identity registration response parsing result information to the key management master node.

[0119] Step S17: the key management master node obtains the identity registration response parsing result in response to receiving the identity registration response parsing result information.

[0120] refer to Figure 4 In the above-mentioned key management method, the security of the key management slave node is verified based on the key management slave node registration information pre-existing in the key management master node and the identification information and identity token information of the key management slave node obtained by decrypting the key seed acquisition request information, so as to determine the security of the key management slave node. The key management slave node registration information pre-existing in the key management master node is obtained by registering the electronic device involved in the key management system when the preparation is completed. In a possible implementation method of the key management method of the present application, the key management method includes an identity registration process of the key management slave node. Based on the identity registration process of the key management slave node, the key management slave node registration information is generated and saved in the key management master node.

[0121] refer to Figure 4Specifically, the specific steps of generating and saving the registration information of the key management slave node in the key management master node include: the key management master node sends the node identity registration notification information to the key management slave node. The key management slave node generates the corresponding identity registration request information based on the received node identity registration notification information, and encrypts the identity registration request. The key management slave node sends the encrypted identity registration request information to the key management master node. The identity registration request information generated by the key management slave node includes: the identification information of the key management slave node. Furthermore, the identification information of the key management slave node can be the name and serial number information.

[0122] The key management master node decrypts the name and serial number information of the key management slave node based on the received key management slave node identity registration request. The key management master node generates the identity token and identity key corresponding to the key management slave node based on the name and serial number of the key management slave node, and stores the identification information, identity token and identity key of the key management slave node in the key management master node. The key management master node encrypts the identification information, identity token and identity key of the key management slave node into identity registration response information, and sends the identity registration response information to the corresponding key management slave node. The key management slave node receives the corresponding identity registration response information. The key management slave node decrypts the received identity registration response information to obtain the identification information, identity token and identity key of the key management slave node, and stores the decrypted identification information, identity token and identity key of the key management slave node in the key management slave node. The key management slave node generates the identity registration response parsing result and sends it to the key management master node. The key management master node determines that the key management slave node receives the identification information, identity token and identity key of the key management slave node based on the received identity registration response parsing result.

[0123] The identity key is used for encryption and / or decryption keys when the key management master node and the key management slave node corresponding to the identity key interact with each other to generate key seeds.

[0124] refer to Figure 5 , Figure 5 A schematic diagram of another process for generating key management slave node registration information in the key management method provided in an embodiment of the present application.

[0125] In a possible implementation of the key management method of the present application, the key management master node sends node identity registration notification information to the key management slave node, including: Step S10: The key management master node generates node identity registration notification information in response to receiving node identity registration instruction information sent by the diagnostic tool.

[0126] Specifically, refer to Figure 5The key management slave node identity registration step further includes: before the key management master node sends the node identity registration notification information to the key management slave node, the key management master node receives the node identity registration instruction information generated by the external diagnostic device. The key management master node generates the node identity registration notification information based on the received node identity registration instruction information and sends it to the key management slave node to execute the subsequent steps S11, S12, S13, S14, S15, S16 and S17.

[0127] refer to Figure 5 Furthermore, the key management method further comprises the following steps:

[0128] Step S18: The diagnostic tool sends identity registration result confirmation information.

[0129] Step S19: The key management master node receives the identity registration result confirmation information sent by the diagnostic tool. Step S20: The key management master node generates identity registration result response information based on the identity registration response analysis result, and sends the identity registration result response information to the diagnostic tool.

[0130] Step S21: the diagnostic tool obtains the identity registration result in response to receiving the identity registration result response information.

[0131] Specifically, refer to Figure 5 , after the key management master node obtains the identity registration response parsing result, the key management master node responds to the identity registration result determination information sent by the received external diagnostic tool. After receiving the identity registration result determination information, the key management master node generates identity registration result response information based on the identity registration response parsing result, and sends the identity registration result response information to the external diagnostic tool. The external diagnostic tool parses and obtains the identity registration result based on the received identity registration result response information, thereby determining that the identity registration of the key management slave node is completed. After the diagnostic tool determines that the identity registration of the key management slave node is completed, the diagnostic tool sends the key seed distribution instruction information to the key management master node to execute the subsequent steps S01, step S0, step S1, step S2, step S3, step S31, step S32, step S33, step S34 and step S4.

[0132] In a possible implementation of the key management method of the present application, the node identity registration instruction information includes node identity token validity period information, and the key management method further includes: the key management master node manages the identity token validity period of the key management slave node based on the node identity token validity period information.

[0133] In the above key management method, when verifying the security of the key management slave node, if the validity period of the identity token of the key management slave node is invalid, the key management slave node needs to re-register the identity information. The setting of the validity period of the identity token of the key management slave node can be set in the key management master node based on the usage scenario of the electronic device designed by the key management system, and can also be set in the node identity instruction information sent by the diagnostic tool.

[0134] Furthermore, in a possible implementation of the key management method of the present application, the node identity instruction information sent by the diagnostic tool may include node identity token validity period information. Setting the node identity token validity period information in the node identity instruction information can determine the corresponding node identity token validity period information based on the to-be-used scenario of the key management system, so that different node identity token validity period information can be set in different usage scenarios, thereby making it easier to manage keys in electronic devices involved in the key management system.

[0135] In addition, in the current application scenario, the electronic devices involved in the key management system can trigger the generation of node identity instruction information based on the diagnostic tool, thereby modifying the validity period information of the node identity token.

[0136] In a possible implementation of the key management method of the present application, the node identity registration instruction information includes key seed distribution cycle information, and the key management method further includes:

[0137] The key management master node manages the key seed distribution time based on the key seed distribution cycle information.

[0138] In the above-mentioned key management method, the key management master node sends node identity registration notification information to the key management slave node based on the node identity registration instruction information sent by the diagnostic tool. Further, in a possible implementation of the key management method of the present application, key seed distribution cycle information may be provided in the node identity registration instruction information sent by the diagnostic tool. The key management master node may periodically generate key seed distribution notification information based on the key seed distribution cycle information, thereby periodically generating key seeds.

[0139] Furthermore, by setting the key seed distribution cycle information in the node identity registration instruction information, the corresponding key seed distribution cycle information can be determined based on the usage scenario of the key management system, so that different key seed distribution cycle information can be set in different usage scenarios, which is more convenient for key management in electronic devices involved in the key management system.

[0140] In a possible implementation of the key management method of the present application, the identification information is the name and / or serial number information of the electronic device involved in the key management slave node.

[0141] In a possible implementation of the key management method of the present application, the identification information of the key management slave node may be the name of the electronic device corresponding to the key management slave node and / or the serial number information of the electronic device. The key management master node may more accurately and conveniently compare the identification information and identity token information of the key management slave node obtained by decryption with the identification information and identity token information of the key management slave node in the pre-stored key management slave node registration information based on the name of the electronic device corresponding to the key management slave node and / or the serial number information of the electronic device.

[0142] In a possible implementation manner of the key management method of the present application, the key management method further includes: the key management slave node stores the generated key in the memory of the key management slave node.

[0143] In the above-mentioned key management method, the generated key seed, key and identification information of the key management slave node, and identity token information are stored in the key management master node and the key management slave node. Furthermore, in a possible implementation of the key management method of the present application, the generated key seed, key and identification information of the key management slave node, and identity token information are stored in the memory of the key management master node and the key management slave node. Storing the generated key seed, key and identification information of the key management slave node, and identity token information in the memory of the key management master node and the key management slave node increases the difficulty for an attacker to directly extract the firmware and obtain the key, and ensures the security of the key seed, key and identification information of the key management slave node, and identity token information.

[0144] In a possible implementation of the key management method of the present application, the key management method also includes: the key management slave node decrypts the target data based on the old key generated by the old key seed, encrypts the target data based on the key generated by the new key seed, and deletes the old key seed and the old key.

[0145] In the above-mentioned key management method, the currently required key is generated according to the key seed generated in the last power-on cycle of the electronic device to which the key management system is applied, and the key seed can be updated periodically based on the key seed distribution cycle, so there are old key seeds and new key seeds in the key management master node and the key management slave node.

[0146] Furthermore, in a possible implementation of the key management method of the present application, after the key management slave node generates an old key to decrypt target data based on the old key seed, the key management slave node deletes the old key and the old key seed.

[0147] Furthermore, when the key management slave node deletes an old key seed, it sends old key seed deletion information to the key management master node, and the key management master node deletes the old key seed in response to the received old key seed deletion information.

[0148] In a possible implementation of the key management method of the present application, the key management method also includes that the key management slave node destroys the key seed in any of the following situations: obtaining a new key seed; using up the key seed; receiving a key seed destruction instruction predefined by the system.

[0149] In a possible implementation of the key management method of the present application, the key management method further includes: destroying the key seed. Specific situations in which the key management master node and the key management slave node destroy the key seed include: in the first situation, when a new key seed is obtained and the electronic device involved in the key management system starts a new power-on cycle, a key is generated based on the new key seed and the old key seed is destroyed, wherein the old key seed may be an unused key seed. In the second situation, when the current key seed is used up and a new key seed has been generated in the key management master node, the electronic device involved in the key management system starts a new power-on cycle and the old key seed is destroyed. In the third situation, when the key management master node and the key management slave node receive a key seed destruction instruction predefined by the system, the key seed is destroyed, wherein the key management master node and the key management slave node receive a key seed destruction instruction predefined by the system including: when the vehicle is resold or the vehicle is scrapped, the system triggers the generation of a key seed destruction instruction.

[0150] In a possible implementation of the key management method of the present application, the key management system further includes a hardware security module, the hardware security module includes a random number generator, and the key random number is generated by the random number generator.

[0151] In a possible implementation of the key management method of the present application, the key management system also includes a hardware security module. The key management master node interacts with the hardware security module. A random number generator is provided in the hardware security module, and a key seed is generated based on the random number generator of the hardware security module. The key generated based on the random number generator can effectively ensure that the key seed information generated in each batch cannot be predicted by the outside, thereby ensuring the security of the key seed.

[0152] In a possible implementation manner of the key management method of the present application, the key management method further includes: encrypting and transmitting information transmitted between the key management master node and the key management slave node based on a preset key.

[0153] In a possible implementation of the key management method of the present application, during the identity registration process of the key management slave node, the identity registration request information generated by the key management slave node and the key management slave node registration information generated by the key management master node are encrypted or decrypted based on a preset key. The preset key is an encryption key pre-set in the key management master node and the key management slave node. In addition, the preset key can be protected based on a memory or a white box.

[0154] In a possible implementation of the key management method of the present application, the electronic devices involved in the key management master node and the key management slave node are electronic control units.

[0155] In a possible implementation of the key management method of the present application, the key management master node and the key management slave node are respectively arranged in different electronic control units. Further, the electronic control unit corresponding to the key management master node is different from the electronic control unit corresponding to the key management slave node. A hardware security module is arranged in the electronic control unit corresponding to the key management master node.

[0156] refer to Figure 6 , Figure 6 A schematic diagram of the structure of a key management system provided in another embodiment of the present application.

[0157] refer to Figure 6 In another embodiment of the present application, a key management system is provided, which includes: a first electronic control unit and a second electronic control unit. The first electronic control unit includes: a key management master node. The second electronic control unit includes: a key management slave node. The key management master node includes: a hardware security module, a key seed distribution module, a node information storage module, a key information storage module and a node identity registration module, and the hardware security module includes: a random number generator. The key management slave node includes: a key seed management module, a key seed storage module, a node identity information management module and a node identity information storage module.

[0158] refer to Figure 6 , further, in the key management system, the node information storage module is used to store the identification information and identity token information of each key management slave node that interacts with the key management master node. The key information storage module is used to store each key seed and key seed batch number, identity key and preset key generated in the hardware security module. The node identity information storage module is used to store the identification information and identity token information of the key management slave node. The key seed storage module is used to store the key seed received by the key management slave node and the key seed batch number, identity key and preset key corresponding to the key seed.

[0159] refer to Figure 6Furthermore, in the key management system, the node identity information management module is used to call the node identity information storage module to generate identity registration request information, which is encrypted based on a preset key and sent to the node identity registration module; the node identity registration module is used to receive the identity registration request information, decrypt the identity registration request information based on a preset key, generate the identification information, identity token information and identity key of the key management slave node based on the identity registration request information, and send them to the key management slave node, and send the identification information and identity token information of the key management slave node to the node information storage module for storage.

[0160] refer to Figure 6 Further, in the key management system, the key seed management module is used to send key seed acquisition request information to the key seed distribution module; the key seed distribution module is used to receive the key seed acquisition request information, decrypt the key seed acquisition request information based on the identity key, and send the key seed acquisition request information to the hardware security module; the random number generator in the hardware security module is used to generate the key seed and the key seed batch number based on the received key seed distribution information, and encrypt the key seed and the key seed batch number based on the identity key and send them to the key seed distribution module; the key seed distribution module is used to receive and decrypt based on the identity key to obtain the key seed and the key seed batch number, send the key seed and the key seed batch number to the key seed management module, and send the key seed and the key seed batch number to the key information storage module for storage. The key seed management module is used to receive the key seed and the key seed batch number, and send the key seed and the key seed batch number to the key seed storage module for storage.

[0161] The node identity registration module is also used to receive node identity registration instruction information sent by the diagnostic tool.

[0162] When managing keys based on the above-mentioned key management system, the diagnostic tool triggers the key management slave node identity registration information; the key management master node generates node identity registration notification information in response to receiving the node identity registration instruction information sent by the diagnostic tool, and sends the node identity registration notification information to the key management slave node; the key management slave node generates and sends identity registration request information to the key management master node in response to receiving the node identity registration notification information; the key management master node generates identity token information and identity key information of the key management slave node in response to receiving the identity registration request information, and obtains the key management slave node registration information; the key management master node generates identity registration response information based on the key management slave node registration information and sends it to the key management slave node; In response to receiving the identity registration response information, the key management slave node parses the identity token information and identity key information of the key management slave node from the identity registration response information for storage, and sends the identity registration response parsing result information to the key management master node; in response to receiving the identity registration response parsing result information, the key management master node obtains the identity registration response parsing result; the diagnostic tool sends the identity registration result confirmation information to the key management master node; the key management master node receives the identity registration result confirmation information sent by the diagnostic tool, generates the identity registration result response information based on the identity registration response parsing result, and sends the identity registration result response information to the diagnostic tool; in response to receiving the identity registration result response information, the diagnostic tool obtains the identity registration result.

[0163] The diagnostic tool determines that the key management slave node identity registration is complete. The diagnostic tool sends a key seed distribution instruction to the key management master node; the key management master node generates a key seed distribution notification message in response to receiving the key seed distribution instruction message sent by the diagnostic tool; the key management slave node sends a key seed acquisition request message to the key management master node when receiving the key seed distribution notification message sent by the key management master node; the key management master node performs security verification on the key management slave node in response to receiving the key seed acquisition request message sent by the key management slave node; if the security verification passes, the key management master node sends a key seed acquisition response message to the key management slave node; the key management slave node responds to receiving the key seed distribution notification message. The key management slave node sends key seed acquisition result information to the key management master node; the key management master node obtains the key seed acquisition result in response to receiving the key seed acquisition result information; the key management master node generates key seed acquisition status information based on the key seed acquisition result in response to receiving the key seed acquisition status determination information sent by the diagnostic tool, and sends the key seed acquisition status information to the diagnostic tool; the diagnostic tool obtains the key seed acquisition status in response to receiving the key seed acquisition status information; when there is a need to use the key, the key management slave node generates a key according to the key seed.

[0164] Based on the above process, key seeds can be generated periodically to generate the keys required for business encryption.

[0165] Figure 7 A schematic diagram of the structure of a vehicle provided by another embodiment of the present application. In a second aspect, another embodiment of the present application discloses a vehicle, such as Figure 7 As shown, the vehicle includes a key management system, which includes a key management master node and multiple key management slave nodes. The key management master node and the multiple key management slave nodes interact to implement a key management method as described in any one of the above embodiments.

[0166] It should be noted that, in addition to the implementation methods of the present invention described in the above-mentioned specific embodiments, those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention is introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation method. On the contrary, the purpose of introducing the invention in conjunction with the implementation method is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the above description contains many specific details, and the present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0167] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0168] In the description of this embodiment, it should also be noted that, unless otherwise clearly specified and limited, the term "setting" can be understood by ordinary technicians in this field in specific circumstances as the specific meaning of the above term in this embodiment.

[0169] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A key management method, characterized in that: Applied to a key management system, the key management system includes a key management master node and multiple key management slave nodes; the key management method includes: In response to receiving the key seed acquisition request information sent by the key management slave node, the key management master node performs security verification on the key management slave node, and sends key seed acquisition response information to the key management slave node if the security verification passes, wherein the key seed acquisition response information includes key seed information, and the key seed information includes a key seed, and the key seed is generated by the key management master node based on a key random number; The key management slave node obtains the key seed according to the key seed acquisition response information in response to receiving the key seed acquisition response information, and generates a key according to the key seed for business encryption processing when there is a key usage requirement.

2. The key management method according to claim 1, characterized in that: The key management method further comprises: When receiving the key seed distribution notification information sent by the key management master node, the key management slave node sends the key seed acquisition request information to the key management master node.

3. The key management method according to claim 1 or 2, characterized in that: The key management method further comprises: The key management master node generates the key seed distribution notification information in response to receiving the key seed distribution instruction information sent by the diagnostic tool; or The key management master node generates the key seed distribution notification information according to a preset key seed distribution cycle.

4. The key management method according to claim 3, characterized in that: The key seed distribution period is determined according to a power-on period of an electronic device involved in the key management system.

5. The key management method according to any one of claims 1 to 4, characterized in that: The key seed acquisition request information includes the identification information and identity token information of the key management slave node, and the key management master node performs security verification on the key management slave node, including: The key management master node parses the identification information and identity token information of the key management slave node from the key seed acquisition request information, and performs security verification on the key management slave node based on the identification information and identity token information of the key management slave node and the key management slave node registration information, wherein the key management slave node registration information includes the identification information, identity token information and validity information of the identity token information of the key management slave node registered with the key management master node. If the identification information and identity token information of the key management slave node exist in the key management slave node registration information and the identity token information is valid, the security verification result of the key management slave node is that the security verification passes; if the identification information and identity token information of the key management slave node do not exist in the key management slave node registration information, or the identity token information is invalid, the security verification result of the key management slave node is that the security verification fails.

6. The key management method according to claim 5, characterized in that: The key management slave node registration information is generated in the following manner: The key management master node sends node identity registration notification information to the key management slave node; In response to receiving the node identity registration notification information, the key management slave node sends identity registration request information to the key management master node, wherein the identity registration request information includes identification information of the key management slave node; In response to receiving the identity registration request information, the key management master node generates identity token information and identity key information of the key management slave node, obtains the key management slave node registration information, and generates identity registration response information and sends it to the key management slave node, wherein the identity registration response information includes the identity token information and identity key information of the key management slave node, and the identity key information is used to perform encryption and decryption processing on the identity token information and the key seed information; In response to receiving the identity registration response information, the key management slave node parses the identity token information and identity key information of the key management slave node from the identity registration response information for storage, and sends the identity registration response parsing result information to the key management master node; The key management master node obtains the identity registration response parsing result in response to receiving the identity registration response parsing result information.

7. The key management method according to claim 6, characterized in that: The key management master node sends node identity registration notification information to the key management slave node, including: The key management master node sends node identity registration notification information to the key management slave node in response to receiving the node identity registration instruction information sent by the diagnostic tool; The method further comprises: The key management master node generates identity registration result response information based on the identity registration response analysis result, and sends the identity registration result response information to the diagnostic tool; The diagnostic tool obtains the identity registration result in response to receiving the identity registration result response information.

8. The key management method according to claim 7, characterized in that: The node identity registration instruction information includes node identity token validity period information, and the key management method further includes: The key management master node manages the validity period of the identity token of the key management slave node based on the node identity token validity period information.

9. The key management method according to claim 7 or 8, characterized in that: The node identity registration instruction information includes key seed distribution cycle information, and the key management method further includes: The key management master node manages the key seed distribution time based on the key seed distribution cycle information.

10. The key management method according to any one of claims 5 to 9, characterized in that: The identification information is the name and / or serial number information of the electronic device involved in the key management slave node.

11. The key management method according to any one of claims 1 to 10, characterized in that: The key management slave node generates a key according to the key seed when there is a demand for key use, including: When there is a demand for key use, the key management slave node generates the key according to the key seed generated in the last power-on cycle of the electronic device involved in the key management system.

12. The key management method according to any one of claims 1 to 11, characterized in that: The key management method further comprises: The key management slave node stores the generated key in the memory of the key management slave node.

13. The key management method according to any one of claims 1 to 12, characterized in that: The key management method further comprises: The key management slave node generates an old key based on the old key seed, decrypts the target data, generates a new key based on the new key seed, encrypts the target data, and deletes the old key seed and the old key.

14. The key management method according to any one of claims 1 to 13, characterized in that: The key management method further includes, the key management slave node destroying the key seed in any of the following situations: Obtaining a new key seed; Finish using the key seed; Receive the key seed destruction instruction set by the system predefined settings.

15. The key management method according to any one of claims 1 to 14, characterized in that: The key management system further includes a hardware security module, and the hardware security module includes a random number generator. The key random number is generated by the random number generator and sent to the key management master node.

16. The key management method according to any one of claims 1 to 15, characterized in that: The key management method further comprises: The information transmitted between the key management master node and the key management slave node is encrypted and transmitted based on a preset key.

17. The key management method according to any one of claims 1 to 16, characterized in that: The electronic devices involved in the key management master node and the key management slave node are electronic control units.

18. A vehicle, characterized in that: The vehicle includes a key management system, which includes a key management master node and multiple key management slave nodes. The key management master node and the key management slave nodes interact to implement the key management method as described in any one of claims 1-17.

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