CN117296294A - Method, device, equipment and storage medium for generating key of proximity communication service - Google Patents

Abstract

The application provides a method, a device, equipment and a storage medium for generating a key of a proximity communication service, wherein the method comprises the following steps: and deriving a second key of the user plane and the control plane in the same derivation mode based on a first key, wherein the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using a PC5 unicast link for communication. The method can simplify the key hierarchy of ProSe.

Description

Translated fromChinese

邻近通信业务的密钥生成方法、装置、设备及存储介质Key generation method, device, equipment and storage medium for proximity communication service技术领域Technical field

本申请涉及通信领域，特别涉及一种邻近通信业务的密钥生成方法、装置、设备及存储介质。The present application relates to the field of communications, and in particular to a key generation method, device, equipment and storage medium for proximity communication services.

背景技术Background technique

5G(5th Generation System，第五代移动通信系统)ProSe(Proximity-based Services，邻近通信业务)UE-to-Network(U2N，终端到网络)Relay(中继)实现了5G网络和终端之间的间接通信。例如，对于不在网络覆盖范围内的远端终端，可以通过中继终端接入5G网络。考虑到安全参数分布的差异，U2N中继通信的安全解决方案可以分为用户面的方案和控制面的方案。5G (5th Generation System, fifth generation mobile communication system) ProSe (Proximity-based Services, proximity communication service) UE-to-Network (U2N, terminal to network) Relay (relay) realizes the connection between the 5G network and the terminal Indirect communication. For example, remote terminals that are not within the network coverage can access the 5G network through relay terminals. Considering the differences in security parameter distribution, security solutions for U2N relay communications can be divided into user plane solutions and control plane solutions.

相关技术中，3GPP(3rd Generation Partnership Project，第三代合作伙伴计划)TS(Technical Specification，技术规范)33.503给出了U2N中继通信控制面的用户面密钥层次结构，以及控制面密钥层次结构。Among related technologies, 3GPP (3rd Generation Partnership Project, 3rd Generation Partnership Project) TS (Technical Specification, Technical Specification) 33.503 provides the user plane key hierarchy of the U2N relay communication control plane, as well as the control plane key hierarchy. structure.

相关技术中的ProSe密钥层次结构较为复杂。The ProSe key hierarchy in the related art is relatively complex.

发明内容Contents of the invention

本申请实施例提供了一种邻近通信业务的密钥生成方法、装置、设备及存储介质，可以简化ProSe的密钥层次结构。Embodiments of the present application provide a key generation method, device, equipment and storage medium for proximity communication services, which can simplify the key hierarchy of ProSe.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成方法，所述方法由核心网设备执行，所述方法包括：According to one aspect of the present application, a key generation method for proximity communication services is provided. The method is executed by a core network device. The method includes:

基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。The second key for the user plane and the control plane is derived in the same derivation method based on the first key. The first key is the PC5 root key of the entity using the proximity communication service. The second key is the PC5 root key for the entity using the proximity communication service. The root key for relay traffic between two entities communicating on a unicast link.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成方法，所述方法由远端终端执行，所述方法包括：According to one aspect of the present application, a key generation method for proximity communication services is provided. The method is executed by a remote terminal. The method includes:

基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The second key for the user plane and the control plane is derived in the same way based on the first key. The first key is the PC5 root key of the entity using the proximity communication service. The second key is the PC5 root key for the entity using the proximity communication service. Describes the relay service root key between two entities communicating on the PC5 unicast link.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成方法，所述方法由中继终端执行，所述方法包括：According to one aspect of the present application, a key generation method for proximity communication services is provided. The method is executed by a relay terminal, and the method includes:

获取第二密钥，所述第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。Obtain a second key, which is a user plane and/or control plane key derived in the same derivation method based on the first key, where the first key is the entity using the proximity communication service. PC5 root key, the second key is a relay service root key between two entities communicating using the PC5 unicast link.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成装置，所述装置包括：According to one aspect of the present application, a key generation device for proximity communication services is provided, and the device includes:

第一生成模块，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。The first generation module is configured to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成装置，所述装置包括：According to one aspect of the present application, a key generation device for proximity communication services is provided, and the device includes:

第二生成模块，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The second generation module is configured to derive the second key of the user plane and the control plane based on the first key in the same derivation manner, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

根据本申请的一个方面，提供了一种邻近通信业务的密钥生成装置，所述装置包括：According to one aspect of the present application, a key generation device for proximity communication services is provided, and the device includes:

第三收发模块，用于获取第二密钥，所述第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密 钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The third transceiver module is used to obtain a second key. The second key is a user plane and/or control plane key derived in the same derivation method based on the first key. The first key is Using the PC5 root key of the entity adjacent to the communication service, the second key is the relay service root key between the two entities communicating using the PC5 unicast link.

根据本申请实施例的一个方面，提供了一种核心网设备，所述核心网设备包括处理器；According to one aspect of the embodiment of the present application, a core network device is provided, and the core network device includes a processor;

所述处理器，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。The processor is configured to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

根据本申请实施例的一个方面，提供了一种终端设备，所述终端设备包括处理器；According to an aspect of an embodiment of the present application, a terminal device is provided, the terminal device including a processor;

所述处理器，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The processor is configured to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

根据本申请实施例的一个方面，提供了一种终端设备，所述终端设备包括收发器；According to one aspect of the embodiment of the present application, a terminal device is provided, the terminal device includes a transceiver;

所述收发器，用于获取第二密钥，所述第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The transceiver is used to obtain a second key. The second key is a user plane and/or control plane key derived in the same derivation method based on the first key. The first key is Using the PC5 root key of the entity adjacent to the communication service, the second key is the relay service root key between the two entities communicating using the PC5 unicast link.

根据本申请的一个方面，提供了一种计算机可读存储介质，所述存储介质中存储有计算机程序，所述计算机程序用于被处理器执行，以实现如上所述的方法。According to one aspect of the present application, a computer-readable storage medium is provided, and a computer program is stored in the storage medium, and the computer program is used to be executed by a processor to implement the method as described above.

根据本申请的一个方面，提供了一种芯片，所述芯片包括可编程逻辑电路和/或程序指令，当所述芯片运行时，用于实现如上所述的方法。According to one aspect of the present application, a chip is provided. The chip includes programmable logic circuits and/or program instructions for implementing the method as described above when the chip is run.

根据本申请的一个方面，提供了一种计算机程序产品或计算机程序，所述计算机程序产品或计算机程序包括计算机指令，所述计算机指令存储在计算机可读存储介质中，处理器从所述计算机可读存储介质读取并执行所述计算机指令，以实现如上所述的方法。According to one aspect of the present application, a computer program product or computer program is provided. The computer program product or computer program includes computer instructions. The computer instructions are stored in a computer-readable storage medium. The processor can read the computer instructions from the computer-readable storage medium. The reading storage medium reads and executes the computer instructions to implement the method as described above.

本申请提供的技术方案至少具有如下有益效果：The technical solution provided by this application has at least the following beneficial effects:

通过基于第一密钥使用相同的衍生方式衍生得到用户面和控制面的第二密钥，使用户面和控制面的密钥层次结构相统一，简化ProSe的密钥层次结构，降低了核心网设备和终端设备执行ProSe安全流程的负担。By using the same derivation method based on the first key to derive the second keys for the user plane and the control plane, the key hierarchies of the user plane and the control plane are unified, simplifying the key hierarchy of ProSe and reducing the cost of the core network. The burden on devices and end devices to implement ProSe security processes.

附图说明Description of drawings

此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：The drawings described here are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the attached picture:

图1是本申请实施例的通信系统的示意图；Figure 1 is a schematic diagram of a communication system according to an embodiment of the present application;

图2是本申请一个实施例提供的U2N中继通信的示意图；Figure 2 is a schematic diagram of U2N relay communication provided by an embodiment of the present application;

图3是本申请一个实施例提供的U2U中继通信的示意图；Figure 3 is a schematic diagram of U2U relay communication provided by an embodiment of the present application;

图4是本申请一个实施例提供的密钥层次结构的示意图；Figure 4 is a schematic diagram of a key hierarchy provided by an embodiment of the present application;

图5是本申请一个实施例提供的密钥层次结构的示意图；Figure 5 is a schematic diagram of a key hierarchy provided by an embodiment of the present application;

图6是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 6 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图7是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 7 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图8是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 8 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图9是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 9 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图10是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 10 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图11是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 11 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图12是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 12 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图13是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 13 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图14是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 14 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图15是本申请一个实施例提供的一种邻近通信业务的密钥生成方法的流程图；Figure 15 is a flow chart of a key generation method for proximity communication services provided by an embodiment of the present application;

图16是本申请一个实施例提供的一种邻近通信业务的密钥生成装置的框图；Figure 16 is a block diagram of a key generation device for proximity communication services provided by an embodiment of the present application;

图17是本申请一个实施例提供的一种邻近通信业务的密钥生成装置的框图；Figure 17 is a block diagram of a key generation device for proximity communication services provided by an embodiment of the present application;

图18是本申请一个实施例提供的一种邻近通信业务的密钥生成装置的框图；Figure 18 is a block diagram of a key generation device for proximity communication services provided by an embodiment of the present application;

图19是本申请一个实施例提供的一种通信设备的框图。Figure 19 is a block diagram of a communication device provided by an embodiment of the present application.

具体实施方式Detailed ways

下文中将参考附图并结合实施例来详细说明本申请。需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。The present application will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other.

需要说明的是，本申请的说明书和权利要求书及上述附图中的术语“第一”、“第二”等是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。It should be noted that the terms "first", "second", etc. in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

首先对本申请中涉及的缩写进行简介：First, a brief introduction to the abbreviations involved in this application:

KDF(Key Derivation Function，密钥衍生算法)：一种将一个密钥衍生为一个新密钥的算法。KDF (Key Derivation Function, key derivation algorithm): an algorithm that derives a key into a new key.

邻近通信业务(Proximity-based Services，ProSe)，也称为D2D(Device-to-Device)通信是由3GPP组织提出的一种点到点的无线通信技术，它可以在蜂窝通信系统的控制下允许终端之间利用小区无线资源直接进行通信(直通/直连通信)，而不经过蜂窝网络中转。作为面向5G的关键候选技术，ProSe能够提升通信系统的频谱效率，减轻系统负荷，在一定程度上解决无线通信系统频谱资源匮乏的问题。同时，由于降低了通信距离，ProSe还可以降低移动终端发射功率，减少电池消耗，提高终端续航时间。Proximity-based Services (ProSe), also known as D2D (Device-to-Device) communication, is a point-to-point wireless communication technology proposed by the 3GPP organization. It can be allowed under the control of the cellular communication system. Terminals use cell wireless resources to communicate directly (pass-through/direct-connect communication) without going through the cellular network for relay. As a key candidate technology for 5G, ProSe can improve the spectrum efficiency of communication systems, reduce system load, and solve the problem of lack of spectrum resources in wireless communication systems to a certain extent. At the same time, due to the reduced communication distance, ProSe can also reduce the transmission power of mobile terminals, reduce battery consumption, and improve terminal life.

请参考图1，其示出了本申请一个实施例提供的通信系统100的示意图。该通信系统100可以包括：终端设备10、接入网设备20和核心网设备30。Please refer to FIG. 1 , which shows a schematic diagram of a communication system 100 provided by an embodiment of the present application. The communication system 100 may include: terminal equipment 10, access network equipment 20 and core network equipment 30.

终端设备10可以指用户设备(User Equipment，UE)、接入终端、用户单元、用户站、移动站、移动台(Mobile Station，MS)、远方站、远程终端、移动设备、无线通信设备、用户代理或用户装置。可选地，终端设备10还可以是蜂窝电话、无绳电话、会话启动协议(Session Initiation Protocol，SIP)电话、无线本地环路(Wireless Local Loop，WLL)站、个人数字处理(Personal Digita1Assistant，PDA)、具有无线通信功能的手持设备、计算设备或连接到无线调制解调器的其它处理设备、车载设备、可穿戴设备，第五代移动通信系统(5th Generation System，5GS)中的终端设备或者未来演进的公用陆地移动通信网络(Pub1ic Land Mobi1e Network，PLMN)中的终端设备等，本申请实施例对此并不限定。为方便描述，上面提到的设备统称为终端设备。终端设备10的数量通常为多个，每一个接入网设备20所管理的小区内可以分布一个或多个终端设备10。The terminal equipment 10 may refer to user equipment (User Equipment, UE), access terminal, user unit, user station, mobile station, mobile station (Mobile Station, MS), remote station, remote terminal, mobile equipment, wireless communication equipment, user Agent or user device. Optionally, the terminal device 10 may also be a cellular phone, a cordless phone, a Session Initiation Protocol (Session Initiation Protocol, SIP) phone, a Wireless Local Loop (WLL) station, or a Personal Digital Assistant (Personal Digital Assistant, PDA). , handheld devices with wireless communication functions, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, terminal devices in the fifth generation mobile communication system (5th Generation System, 5GS) or public utility devices that will evolve in the future. The embodiments of the present application are not limited to terminal equipment in a land mobile communication network (Public Land Mobile Network, PLMN). For convenience of description, the devices mentioned above are collectively referred to as terminal devices. The number of terminal devices 10 is usually multiple, and one or more terminal devices 10 may be distributed in the cell managed by each access network device 20 .

接入网设备20是一种部署在接入网中用以为终端设备10提供无线通信功能的设备。接入网设备20可以包括各种形式的宏基站，微基站，中继站，接入点等等。在采用不同的无线接入技术的系统中，具备接入网设备功能的设备的名称可能会有所不同，例如在5G NR系统中，称为gNodeB或者gNB。随着通信技术的演进，“接入网设备”这一名称可能会变化。为方便描述，本申请实施例中，上述为终端设备10提供无线通信功能的装置统称为接入网设备。可选地，通过接入网设备20，终端设备10和核心网设备30之间可以建立通信关系。示例性地，在长期演进(Long Term Evolution，LTE)系统中，接入网设备20可以是演进的通用陆地无线网(Evolved Universal Terrestrial Radio Access Network，EUTRAN)或者EUTRAN中的一个或者多个eNodeB；在5G NR系统中，接入网设备20可以是无线接入网(Radio Access Network，RAN)或者RAN中的一个或者多个gNB。The access network device 20 is a device deployed in the access network to provide wireless communication functions for the terminal device 10 . The access network device 20 may include various forms of macro base stations, micro base stations, relay stations, access points, etc. In systems using different wireless access technologies, the names of devices with access network device functions may be different. For example, in 5G NR systems, they are called gNodeB or gNB. As communication technology evolves, the name "access network equipment" may change. For convenience of description, in the embodiment of the present application, the above-mentioned devices that provide wireless communication functions for the terminal device 10 are collectively referred to as access network devices. Optionally, through the access network device 20, a communication relationship can be established between the terminal device 10 and the core network device 30. For example, in a Long Term Evolution (LTE) system, the access network device 20 may be an Evolved Universal Terrestrial Radio Access Network (EUTRAN) or one or more eNodeBs in EUTRAN; In the 5G NR system, the access network device 20 may be a radio access network (Radio Access Network, RAN) or one or more gNBs in the RAN.

核心网设备30是部署在核心网中的设备，核心网设备30的功能主要是提供用户连接、对用户的管理以及对业务完成承载，作为承载网络提供到外部网络的接口。例如，5G NR系统中的核心网设备可以包括接入和移动性管理功能(Access and Mobility Management Function，AMF)网元、用户平面功能(User Plane Function，UPF)网元、会话管理功能(Session Management Function，SMF)网元、AUSF(Authentication Server Function鉴权服务器功能)网元、PAnF(ProSe Anchor Function，邻近通信业务锚点功能)网元、PKMF(ProSe Key Management Function，密钥管理功能)网元等。The core network device 30 is a device deployed in the core network. The core network device 30 mainly functions to provide user connections, manage users, and carry services, and serves as an interface for the bearer network to provide to external networks. For example, the core network equipment in the 5G NR system can include Access and Mobility Management Function (AMF) network elements, User Plane Function (UPF) network elements, Session Management Function (Session Management Function, SMF) network element, AUSF (Authentication Server Function) network element, PAnF (ProSe Anchor Function, proximity communication service anchor function) network element, PKMF (ProSe Key Management Function, key management function) network element wait.

在一个示例中，接入网设备20与核心网设备30之间通过某种空口技术互相通信，例如5G NR系统中的NG接口。接入网设备20与终端设备10之间通过某种空口技术互相通信，例如Uu接口。In one example, the access network device 20 and the core network device 30 communicate with each other through some air interface technology, such as the NG interface in the 5G NR system. The access network device 20 and the terminal device 10 communicate with each other through some air interface technology, such as the Uu interface.

本申请实施例中的“5G NR系统”也可以称为5G系统或者NR系统，但本领域技术人员可以理解其含义。本申请实施例描述的技术方案可以适用于5G NR系统，也可以适用于任何无线通信系统，例如，5G NR系统后续的演进系统，B5G、6G等。The “5G NR system” in the embodiment of this application may also be called a 5G system or an NR system, but those skilled in the art can understand its meaning. The technical solutions described in the embodiments of this application can be applied to the 5G NR system, and can also be applied to any wireless communication system, such as subsequent evolution systems of the 5G NR system, B5G, 6G, etc.

本申请实施例的技术方案可以应用于各种通信系统，例如：全球移动通讯(Global System of Mobile Communication，GSM)系统、码分多址(Code Division Multiple Access，CDMA)系统、宽带码分多址(Wideband Code Division Multiple Access，WCDMA)系统、通用分组无线业务(General Packet Radio Service，GPRS)、长期演进(Long Term Evolution，LTE)系统、LTE频分双工(Frequency Division Duplex，FDD)系统、LTE时分双工(Time Division Duplex，TDD)系统、先进的长期演进(Advanced Long Term Evolution，LTE-A)系统、新无线(New Radio，NR)系统、NR系统的演进系统、非授权频段上的LTE(LTE-based access to Unlicensed spectrum，LTE-U)系统、NR-U系统、通用移动通信系统(Universal Mobile Telecommunication System，UMTS)、全球互联微波接入(Worldwide Interoperability for Microwave Access，WiMAX)通信系统、无线局域网(Wireless Local Area Networks，WLAN)、无线保真(Wireless Fidelity，WiFi)、下一代通信系统或其他通信系统等。The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System of Mobile Communication (GSM) system, Code Division Multiple Access (Code Division Multiple Access, CDMA) system, wideband code division multiple access (Wideband Code Division Multiple Access, WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (Long Term Evolution, LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD) system, Advanced Long Term Evolution (LTE-A) system, New Radio (NR) system, evolution system of NR system, LTE on unlicensed frequency band (LTE-based access to Unlicensed spectrum, LTE-U) system, NR-U system, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication system, Wireless Local Area Networks (WLAN), Wireless Fidelity (WiFi), next-generation communication systems or other communication systems, etc.

U2N中继如图2所示，当终端设备位于网络的覆盖范围外(out-of-coverage)，终端设备无法直接接入网络，该终端设备可以通过中继终端12接入网络，该终端设备称为远端终端11。中继终端12与远端终端11之间示例性的可以通过PC5接口进行通信。远端终端为通过中继设备(例如，中继终端)接入网络的终端设备。中继终端是为远端终端提供中继服务，以使远端终端通过中继终端接入网络和与目标终端进行通信的终端设备。U2N relay is shown in Figure 2. When the terminal device is located outside the coverage of the network (out-of-coverage), the terminal device cannot directly access the network. The terminal device can access the network through the relay terminal 12. The terminal device Called remote terminal 11. Communication between the relay terminal 12 and the remote terminal 11 can be carried out through the PC5 interface. The remote terminal is a terminal device that accesses the network through a relay device (for example, a relay terminal). A relay terminal is a terminal device that provides relay services to remote terminals so that the remote terminals can access the network and communicate with the target terminal through the relay terminal.

U2U中继如图3所示，当源终端无法直接到达目标终端13，则源终端可以通过发现一个U2U(UE-to-UE，终端到终端)中继来到达目标终端13，即，源终端通过中继终端12与目标终端13进行通信，则源终端称为远端终端11。远端终端为通过中继设备(例如，中继终端)与目标终端进行通信的终端设备。其中，目标终端与远端终端无法直接建立通信，例如，目标终端与远端终端距离过远。The U2U relay is shown in Figure 3. When the source terminal cannot directly reach the target terminal 13, the source terminal can reach the target terminal 13 by discovering a U2U (UE-to-UE, terminal to terminal) relay, that is, the source terminal When communicating with the target terminal 13 through the relay terminal 12, the source terminal is called the remote terminal 11. The remote terminal is a terminal device that communicates with the target terminal through a relay device (for example, a relay terminal). Among them, the target terminal and the remote terminal cannot directly establish communication. For example, the target terminal and the remote terminal are too far apart.

如图4所示，针对PreSe本申请实施例提供了一种PC5通用密钥层次结构，可以用于用户面和控制面的安全流程。如图5所示，为相关技术(参见3GPP TS 33.503)中提供的控制面和用户面PC5密钥层次结构的示意图，其中，图5(1)为控制面PC5密钥层次结构，图5(2)为用户面PC5密钥层次结构。As shown in Figure 4, the embodiment of this application provides a PC5 universal key hierarchy structure for PreSe, which can be used for the security processes of the user plane and control plane. As shown in Figure 5, it is a schematic diagram of the control plane and user plane PC5 key hierarchy provided in related technologies (see 3GPP TS 33.503). Figure 5(1) is the control plane PC5 key hierarchy, and Figure 5( 2) is the user plane PC5 key hierarchy.

下面结合3GPP TS 33.503中提供的PC5密钥层次结构对本申请实施例提供的PC5通用密钥层次结构进行说明：The following describes the PC5 universal key hierarchy provided by the embodiment of this application in conjunction with the PC5 key hierarchy provided in 3GPP TS 33.503:

1、本申请实施例提供的PC5通用密钥层次结构，在控制面5GPRUK由K_{AUSF_G}衍生得到。1. The PC5 universal key hierarchy provided by the embodiment of this application is derived from K_{AUSF_G} on the control plane 5GPRUK.

如图5(1)所示，相关技术中控制面上的5GPRUK是从K_{AUSF_P}衍生得到的，而K_{AUSF_P}是由K_AUSF衍生得到。K_{AUSF_P}仅用于衍生5GPRUK，K_AUSF为运行主身份认证得到的密钥。As shown in Figure 5(1), 5GPRUK on the control plane in related technologies is derived from K_{AUSF_P} , and K_{AUSF_P} is derived from K_AUSF . K_{AUSF_P} is only used to derive 5GPRUK, and K_AUSF is the key obtained by running master identity authentication.

而本申请实施例中控制面上的5GPRUK是从K_{AUSF_G}衍生得到，K_{AUSF_G}是运行特定业务的身份认证得到的密钥。In the embodiment of this application, 5GPRUK on the control plane is derived from K_{AUSF_G} ,_which is a key obtained from identity authentication for running a specific service.

注：K_{AUSF_G}与K_AUSF不同，K_AUSF是运行主身份认证得到的密钥，K_{AUSF_G}是运行特定业务身份认证得到的密钥。例如，在运行主身份认证后，终端设备还可以再进行针对特定业务的身份认证，在运行特定业务的身份认证得到的密钥称为K_{AUSF_G}。特定业务包括但不限于 ProSe业务、测距业务等。Note: K_{AUSF_G} is different from K_AUSF . K_AUSF is the key obtained by running the main identity authentication, and K_{AUSF_G} is the key obtained by running the specific business identity authentication. For example, after running the main identity authentication, the terminal device can also perform identity authentication for a specific service. The key obtained after running the identity authentication for the specific service is called K_{AUSF_G} . Specific services include but are not limited to ProSe services, ranging services, etc.

2、本申请实施例提供了5GPRUK、K_{NR_U2N_ProSe}的衍生函数，使控制面与用户面相统一。2. The embodiment of this application provides derivative functions of 5GPRUK and K_{NR_U2N_ProSe} to unify the control plane and the user plane.

2.1相关技术中，控制面5GPRUK的衍生函数为：2.1 In related technologies, the derivative function of the control plane 5GPRUK is:

When deriving a 5GPRUK from K_{AUSF_P},the following parameters shall be used to form the input S to the KDF；即：从K_{AUSF_P}衍生到5GPRUK时，应使用以下参数作为KDF的输入S：When deriving a 5GPRUK from K_{AUSF_P} , the following parameters shall be used to form the input S to the KDF; that is: when deriving from K_{AUSF_P} to 5GPRUK, the following parameters shall be used to form the input S to the KDF:

- FC＝0xXX；- FC=0xXX;

- P0＝SUPI(Subscription PermanentIdentifier，用户永久标识符)，即P0是相关技术中5GPRUK的衍生函数的第1个输入参数；- P0 = SUPI (Subscription PermanentIdentifier, user permanent identifier), that is, P0 is the first input parameter of the derivative function of 5GPRUK in related technologies;

- L0＝length of SUPI，即：SUPI的长度，即L0是相关技术中5GPRUK的衍生函数的SUPI的长度；- L0=length of SUPI, that is: the length of SUPI, that is, L0 is the length of SUPI of the derivative function of 5GPRUK in the related technology;

- P1＝relay service code，即：中继业务代码，即P1是相关技术中5GPRUK的衍生函数的第2个输入参数；- P1＝relay service code, that is: relay service code, that is, P1 is the second input parameter of the derived function of 5GPRUK in related technologies;

- L1＝length of relay service code，即：中继业务代码的长度，即L1是相关技术中5GPRUK的衍生函数的中继业务代码的长度；- L1=length of relay service code, that is: the length of the relay service code, that is, L1 is the length of the relay service code of the derivative function of 5GPRUK in the related technology;

The input key KEY is K_{AUSF_P}，即：输入密钥为K_{AUSF_P}。The input key KEY is K_{AUSF_P} , that is: the input key is K_{AUSF_P} .

2.2本申请实施例中，控制面5GPRUK的衍生函数为：2.2 In the embodiment of this application, the derivative function of the control plane 5GPRUK is:

When deriving a 5GPRUK from K_{AUSF_G},the following parameters shall be used to form the input S to the KDF；即：从K_{AUSF_G}衍生到5GPRUK时，应使用以下参数作为KDF的输入S：When deriving a 5GPRUK from K_{AUSF_G} , the following parameters shall be used to form the input S to the KDF; that is: when deriving from K_{AUSF_G} to 5GPRUK, the following parameters shall be used as the input S of the KDF:

- FC＝TBD(to be allocated by 3GPP)，即：待定(由3GPP分配)；- FC=TBD (to be allocated by 3GPP), that is: to be determined (to be allocated by 3GPP);

- P0＝Service indicator(e.g.0x01 for ProSe service；0x02 for Ranging service)，即：业务指示符；例如，0x01表示ProSe业务，0x02表示测距业务，P0是本申请中5GPRUK的衍生函数的第1个输入参数；- P0=Service indicator (e.g.0x01 for ProSe service; 0x02 for Ranging service), that is, service indicator; for example, 0x01 represents ProSe service, 0x02 represents ranging service, and P0 is the first derivative function of 5GPRUK in this application Input parameters;

- L0＝length of Service indicator，即：业务指示符的长度，L0是本申请中5GPRUK的衍生函数的业务指示符的长度；- L0=length of Service indicator, that is: the length of the service indicator, L0 is the length of the service indicator of the derivative function of 5GPRUK in this application;

- P1＝SUPI，即P1是本申请中5GPRUK的衍生函数的第2个输入参数；- P1=SUPI, that is, P1 is the second input parameter of the derivative function of 5GPRUK in this application;

- L1＝length of SUPI，即：SUPI的长度，L1是本申请中5GPRUK的衍生函数的SUPI的长度。- L1=length of SUPI, that is: the length of SUPI, L1 is the length of SUPI of the derivative function of 5GPRUK in this application.

The input key KEY is K_{AUSF_G}，即：输入密钥为K_{AUSF_G}。The input key KEY is K_{AUSF_G} , that is: the input key is K_{AUSF_G} .

2.3本申请实施例中，K_{NR_U2N_ProSe}的衍生函数为：2.3 In the embodiment of this application, the derivative function of K_{NR_U2N_ProSe} is:

When deriving a K_{NR_U2N_Prose} from 5GPRUK,the following parameters shall be used to form the input S to the KDF，即：从5GPRUK衍生到K_{NR_U2N_ProSe}时，应使用以下参数作为KDF的输入S：When deriving_a K_{NR_U2N_Prose} from 5GPRUK, the following parameters shall be used to form the input S to the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Nonce_2，即：随机数2，P0是K_{NR_U2N_ProSe}的衍生函数的第1个输入参数；- P0=Nonce_2, that is: random number 2, P0 is the first input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L0＝length of Nonce_2，即：随机数2的长度，L0是K_{NR_U2N_ProSe}的衍生函数的随机数2的长度；- L0=length of Nonce_2, that is: the length of random number 2, L0 is the length of random number 2 of the derivative function of K_{NR_U2N_ProSe} ;

- P1＝Nonce_1，即：随机数1，P1是K_{NR_U2N_ProSe}的衍生函数的第2个输入参数；- P1=Nonce_1, that is: random number 1, P1 is the second input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L1＝length of Nonce_1，即：随机数1的长度，L1是K_{NR_U2N_ProSe}的衍生函数的随机数1的长度；- L1=length of Nonce_1, that is: the length of the random number 1, L1 is the length of the random number 1 of the derivative function of K_{NR_U2N_ProSe} ;

- P2＝Relay service code，即：中继业务代码，P2是K_{NR_U2N_ProSe}的衍生函数的第3个输入参数；- P2＝Relay service code, that is: relay service code, P2 is the third input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L2＝length of Relay service code，即：中继业务代码的长度，L2是K_{NR_U2N_ProSe}的衍生函数的中继业务代码的长度。- L2=length of Relay service code, that is: the length of the relay service code, L2 is the length of the relay service code of the derivative function of K_{NR_U2N_ProSe} .

The input key KEY is 5GPRUK，即：输入密钥为5GPRUK。The input key KEY is 5GPRUK, that is: the input key is 5GPRUK.

结合2.1、2.2和2.3可见：Combining 2.1, 2.2 and 2.3 shows:

①相关技术中将中继业务代码(Relay service code)作为衍生5GPRUK时的输入。① In related technologies, the relay service code (Relay service code) is used as the input when deriving 5GPRUK.

5GPRUK与Relay service code绑定。5GPRUK is bound to Relay service code.

②而本申请实施例在衍生5GPRUK时将其与K_{AUSF_G}对应的特定业务(Service②In this embodiment of the present application, when deriving 5GPRUK, it will be the specific service (Service) corresponding to K_{AUSF_G} .

indicator)绑定，并不绑定Relay service code。将Relay service code作为衍生K_{NR_U2N_ProSe}时的输入。K_{NR_U2N_ProSe}与Relay service code绑定。indicator) is bound, not the Relay service code. Use Relay service code as input when deriving K_{NR_U2N_ProSe} . K_{NR_U2N_ProSe} is bound to Relay service code.

由于在相关技术的用户面中，PRUK使用的是身份认证得到的密钥，在使用PRUK衍生得到K_NRP时将中继业务代码作为输入，使K_NRP与Relay service code绑定。即，相关技术的控制面中，5GPRUK与Relay service code绑定；相关技术的用户面中K_NRP与Relay service code绑定。处于同一层级的用户面K_NRP与控制面K_{NR_ProSe}所包含的信息并不统一。Since in the user plane of related technologies, PRUK uses the key obtained from identity authentication, when using PRUK to derive K_NRP , the relay service code is used as input, so that K_NRP is bound to the Relay service code. That is, in the control plane of related technologies, 5GPRUK is bound to Relay service code; in the user plane of related technologies, K_NRP is bound to Relay service code. The information contained in the user plane K_NRP and the control plane K_{NR_ProSe} at the same level is not consistent.

而使用本申请提供的控制面5GPRUK、K_{NR_U2N_ProSe}(相当于相关技术中的K_{NR_ProSe}/K_NRP)衍生函数，K_{NR_U2N_ProSe}与Relay service code绑定。进而使其在用户面和控制面上，Relay service code都与K_{NR_U2N_ProSe}绑定，用户面和控制面同一层级的密钥所包含的信息统一(则K_{NR_ProSe}和K_NRP可以合并称为K_{NR_U2N_ProSe})，使用户面和控制面的密钥层次结构统一，得到用户面和控制面通用的PC5密钥层次结构。其中，K_{NR_U2N_ProSe}相当于相关技术中的K_{NR_ProSe}/K_NRP。用户面和控制面同一层级的密钥所包含的信息统一，则K_{NR_ProSe}和K_NRP可以合并称为K_{NR_U2N_ProSe}。Using the control plane 5GPRUK and K_{NR_U2N_ProSe} (equivalent to K_{NR_ProSe} /K_NRP in related technologies) derivative functions provided by this application, K_{NR_U2N_ProSe} is bound to the Relay service code. Then the Relay service code is bound to K_{NR_U2N_ProSe} on both the user plane and control plane, and the information contained in the keys at the same level on the user plane and control plane is unified (then K_{NR_ProSe} and K_NRP can be combined and called K_{NR_U2N_ProSe} ) , unify the key hierarchies of the user plane and the control plane, and obtain a PC5 key hierarchical structure common to the user plane and the control plane. Among them, K_{NR_U2N_ProSe} is equivalent to K_{NR_ProSe} /K_NRP in related technologies. The information contained in the keys at the same level of the user plane and the control plane is unified, so K_{NR_ProSe} and K_NRP can be combined and called K_{NR_U2N_ProSe} .

另外，本申请实施例还提供了5GPRUK ID的衍生函数：In addition, the embodiment of this application also provides the derivative function of 5GPRUK ID:

When deriving the 5GPRUK ID from K_{AUSF_G},the following parameters are used to form the input S to the KDF，即：从K_{AUSF_G}衍生到5GPRUK ID时，应使用以下参数作为KDF的输入S：When deriving the 5GPRUK ID from K_{AUSF_G} , the following parameters are used to form the input S to the KDF, that is: when deriving from K_{AUSF_G} to 5GPRUK ID, the following parameters should be used as the input S of the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Key ID string(e.g."PRUK-ID"for ProSe service,“RRUK-ID”for Ranging service)，即：密钥标识字符串，例如，ProSe业务的密钥标识字符串为“PRUK-ID”、测距业务的密钥标识字符串为“RRUK-ID”，P0是5GPRUK ID的衍生函数的第1个输入参数；- P0＝Key ID string (e.g. "PRUK-ID" for ProSe service, "RRUK-ID" for Ranging service), that is: key identification string, for example, the key identification string of ProSe service is "PRUK-ID" ", the key identification string of the ranging service is "RRUK-ID", and P0 is the first input parameter of the derivative function of 5GPRUK ID;

- L0＝length of key ID string，即：密钥标识字符串的长度，L0是5GPRUK ID的衍生函数的密钥标识字符串的长度。- L0=length of key ID string, that is: the length of the key identification string, L0 is the length of the key identification string of the derivative function of 5GPRUK ID.

- P1＝SUPI，即P1是5GPRUK ID的衍生函数的第2个输入参数；- P1=SUPI, that is, P1 is the second input parameter of the derivative function of 5GPRUK ID;

- L1＝length of SUPI，L1是5GPRUK ID的衍生函数的SUPI的长度。- L1=length of SUPI, L1 is the length of SUPI of the derivative function of 5GPRUK ID.

The input key KEY is K_{AUSF_G}，即：输入密钥为K_{AUSF_G}。The input key KEY is K_{AUSF_G} , that is: the input key is K_{AUSF_G} .

3、本申请实施例提供的PC5通用密钥层次结构，可适用于U2N中继业务和U2U中继业务。3. The PC5 universal key hierarchy provided by the embodiment of this application can be applied to U2N relay services and U2U relay services.

相关技术中仅提供了U2N中继通信的PC5密钥层次结构。根据3GPP TR 33.847，5G ProSe还可以使终端通过U2U中继相互通信。如图3所示，如果源终端不能直接到达目标终端13，源终端将尝试发现一个UE-to-UE Relay(中继)来到达目标终端13。新场景的引入对安全机制提出了新的要求。Only the PC5 key hierarchy for U2N relay communication is provided in the related art. According to 3GPP TR 33.847, 5G ProSe also enables terminals to communicate with each other through U2U relays. As shown in Figure 3, if the source terminal cannot directly reach the target terminal 13, the source terminal will try to find a UE-to-UE Relay to reach the target terminal 13. The introduction of new scenarios puts forward new requirements for security mechanisms.

本申请实施例不仅调整了U2N中继业务的PC5密钥层次结构，还提供了U2U中继业务的PC5密钥层次结构。The embodiment of the present application not only adjusts the PC5 key hierarchy structure of the U2N relay service, but also provides the PC5 key hierarchy structure of the U2U relay service.

其包括由5GPRUK衍生得到的K_{NR_U2U_ProSe}，以及由K_{NR_U2U_ProSe}衍生得到的K_U2U-sess、以及由K_U2U-sess衍生得到的K_U2U-inc、K_U2U-enc。It includes K_{NR_U2U_ProSe} derived from 5GPRUK, K_U2U-sess derived from K_{NR_U2U_ProSe} , and K_U2U-inc and K U2U_-enc derived from K U2U_-sess .

并给出了K_{NR_U2U_ProSe}的衍生函数。And the derivative function of K_{NR_U2U_ProSe} is given.

综上所述，基于图4，本申请实施例提供的PC5通用密钥层次结构总结如下。In summary, based on Figure 4, the PC5 universal key hierarchy provided by the embodiment of this application is summarized as follows.

一、该通用密钥层次结构包括如下密钥：1. The universal key hierarchy includes the following keys:

1、5GPRUK(Prose Remote User Key，邻近通信业务远端用户密钥)1. 5GPRUK (Prose Remote User Key, proximity communication service remote user key)

5GPRUK:The root credential for establishing security of the PC5 unicast link,which can be used for various relay services including U2N relay services and U2U relay services.In user plane,5GPRUK is generated by the 5G PKMF and provided to the remote UE when it is in coverage as specified in 3GPP TS 33.503.In control plane,5GPRUK is derived from K_{AUSF_G},which is a key derived based on 5G Service specific authentication.It may be refreshed by re-running the 5G Service specific authentication.5GPRUK: The root credential for establishing security of the PC5 unicast link, which can be used for various relay services including U2N relay services and U2U relay services. In user plane, 5GPRUK is generated by the 5G PKMF and provided to the remote UE when it is in coverage as specified in 3GPP TS 33.503.In control plane,5GPRUK is derived from K_{AUSF_G} ,which is a key derived based on 5G Service specific authentication.It may be refreshed by re-running the 5G Service specific authentication.

即：5GPRUK：用于安全建立PC5单播链路的根凭证，可用于各种中继业务，包括U2N中继业务和U2U中继业务。在用户面，按照3GPP TS 33.503的规定，5GPRUK由5G PKMF生成并提供给位于覆盖范围内的远端终端。在控制面，5GPRUK由K_{AUSF_G}衍生而来，K_{AUSF_G}是基于5G特定业务身份认证衍生得到的密钥。K_{AUSF_G}可以通过重新运行5G特定业务身份认证进行刷新。Namely: 5GPRUK: The root certificate used to securely establish PC5 unicast links, which can be used for various relay services, including U2N relay services and U2U relay services. On the user plane, according to the provisions of 3GPP TS 33.503, 5GPRUK is generated by 5G PKMF and provided to the remote terminal located within the coverage area. On the control plane, 5GPRUK is derived from K_{AUSF_G} ,_which is a key derived based on 5G specific service identity authentication. K_{AUSF_G} can be refreshed by re-running 5G specific service identity authentication.

Note:K_{AUSF_G} is different from K_AUSF.K_AUSF is a key derived by running the primary authentication.Note:K_{AUSF_G} is different from K_AUSF .K_AUSF is a key derived by running the primary authentication.

即：“K_{AUSF_G}”与“K_AUSF”不同。K_AUSF为运行主身份认证时衍生的密钥。主身份认证可以指终端设备接入网络时所进行的认证。That is: "K_{AUSF_G} " is different from "K_AUSF ". K_AUSF is the key derived when running primary authentication. Primary identity authentication can refer to the authentication performed when the terminal device accesses the network.

Note:In the control plane,the core network function can act as AUSF or PAnF,in the user plane,the core network function can act as 5G PKMF.Note: In the control plane, the core network function can act as AUSF or PAnF, in the user plane, the core network function can act as 5G PKMF.

即：注：在控制面，核心网网元(核心网设备)可以包括AUSF网元或PAnF网元，在用户面，核心网网元可以包括5G PKMF网元。That is: Note: On the control plane, core network elements (core network equipment) can include AUSF network elements or PAnF network elements. On the user plane, core network elements can include 5G PKMF network elements.

针对U2N中继业务(For 5G ProSe U2N service)包括：For U2N relay services (For 5G ProSe U2N service) include:

2、K_{NR_U2N_ProSe}2.K_{NR_U2N_ProSe}

K_{NR_U2N_ProSe}:This is a 256-bit root key bound with a specific U2N relay service and used for establishing security between the U2N Relay and the Remote UE communicating over NR PC5unicast link.K_{NR_U2N_ProSe} :This is a 256-bit root key bound with a specific U2N relay service and used for establishing security between the U2N Relay and the Remote UE communicating over NR PC5unicast link.

即：K_{NR_U2N_ProSe}：与特定的U2N中继业务绑定的256位根密钥，用于在U2N中继终端和的远端终端之间，通过NR PC5单播链路，建立安全通信连接。That is: K_{NR_U2N_ProSe} : A 256-bit root key bound to a specific U2N relay service, used to establish a secure communication connection between the U2N relay terminal and the remote terminal through the NR PC5 unicast link.

3、K_relay-sess3.K_relay-sess

K_relay-sess:This is the 256-bit key that is derived by UE from K_{NR_U2N_ProSe} and is used to derive keys for protecting the specific communication session of a U2N relay service between the UEs.The K_relay-sess is derived per unicast link in the same way as K_NRP-sess specified in TS 33.536.During activated unicast communication session between the UEs,the K_relay-sess may be refreshed by running the rekeying procedure.K_relay-sess :This is the 256-bit key that is derived by UE from K_{NR_U2N_ProSe} and is used to derive keys for protecting the specific communication session of a U2N relay service between the UEs.The K_relay-sess is derived per unicast link in the same way as K_NRP-sess specified in TS 33.536.During activated unicast communication session between the UEs, the K_relay-sess may be refreshed by running the rekeying procedure.

即：K_relay-sess：为256位密钥，由终端(中继终端和/或远端终端)从K_{NR_U2N_ProSe}衍生而来，用于衍生保护终端间特定U2N中继业务通信会话的密钥。K_relay-sess与TS 33.536中规定的K_NRP-sess相同，是按单播链路衍生的。在终端间激活的单播通信会话中，可以通过运行密钥更新过程来刷新K_relay-sess。That is: K_relay-sess : It is a 256-bit key, which is derived from K_{NR_U2N_ProSe} by the terminal (relay terminal and/or remote terminal). It is used to derive the key that protects the specific U2N relay service communication session between terminals. K_relay-sess is the same as K_NRP-sess specified in TS 33.536, and is derived from unicast links. In an active unicast communication session between endpoints, K_relay-sess can be refreshed by running a key update process.

4、K_relay-inc,K_relay-enc4.K_relay-inc ,K_relay-enc

K_relay-inc,K_relay-enc:The K_relay-inc and K_relay-enc are used in the chosen confidentiality and integrity algorithms respectively for protecting the integrity and confidentiality of PC5-S signalling,PC5 RRC signalling,and PC5 user plane data.These keys are equivalent to NRPIK and NRPEK as specified in TS 33.536.They are derived from K_relay-sess and are refreshed automatically every time K_relay-sess is changed.K_relay-inc ,K_relay-enc :The K_relay-inc and K_relay-enc are used in the chosen confidentiality and integrity algorithms respectively for protecting the integrity and confidentiality of PC5-S signaling, PC5 RRC signaling, and PC5 user plane data.These keys are equivalent to NRPIK and NRPEK as specified in TS 33.536.They are derived from K_relay-sess and are refreshed automatically every time K_relay-sess is changed.

即：K_relay-inc、K_relay-enc：为加密算法和完整性算法的密钥，用于保护保护PC5-s信令、PC5 RRC(Radio Resource Control，无线资源控制)信令和PC5用户面数据的完整性和机密性。K_relay-inc、K_relay-enc等价于TS 33.536中指定的NRPIK和NRPEK。K_relay-inc、K_relay-enc由K_relay-sess衍生得到，并在每次K_relay-sess更新时自动更新。That is: K_relay-inc , K_relay-enc : are the keys of the encryption algorithm and integrity algorithm, used to protect PC5-s signaling, PC5 RRC (Radio Resource Control, Radio Resource Control) signaling and PC5 user plane Data integrity and confidentiality. K_relay-inc and K_relay-enc are equivalent to NRPIK and NRPEK specified in TS 33.536. K_relay-inc and K_relay-enc are derived from K_relay-sess and are automatically updated every time K_relay-sess is updated.

针对U2U中继业务包括：U2U relay services include:

5、K_{NR_U2U_ProSe5.KNR_U2U_ProSe}

K_{NR_U2U_ProSe}:This is a 256-bit root key bound with a specific U2U relay service and used for establishing security between the U2U Relay and the remote UE communicating over NR PC5 unicast link.K_{NR_U2U_ProSe} :This is a 256-bit root key bound with a specific U2U relay service and used for establishing security between the U2U Relay and the remote UE communicating over NR PC5 unicast link.

即：K_{NR_U2U_ProSe}：与特定的U2U中继业务绑定的256位根密钥，用于在U2U中继终端与远端终端间，通过NR PC5单播链路，建立安全通信连接。That is: K_{NR_U2U_ProSe} : A 256-bit root key bound to a specific U2U relay service, used to establish a secure communication connection between the U2U relay terminal and the remote terminal through the NR PC5 unicast link.

6、K_U2U-sess6. K_U2U-sess

K_U2U-sess:This is the 256-bit key that is derived by UE from K_{NR_U2U_ProSe} and is used to derive keys for protecting the specific communication session of a U2U relay service between the UEs.The K_U2U-sess is derived per unicast link in the same way as K_NRP-sess specified in TS 33.536.During activated unicast communication session between the UEs,the K_U2U-sess may be refreshed by running the rekeying procedure.K_U2U -sess:This is the 256-bit key that is derived by UE from K_{NR_U2U_ProSe} and is used to derive keys for protecting the specific communication session of a U2U relay service between the UEs.The K_U2U-sess is derived per unicast link in the same way as K_NRP-sess specified in TS 33.536.During activated unicast communication session between the UEs, the K_U2U-sess may be refreshed by running the rekeying procedure.

即：K_U2U-sess：UE(中继终端和/或远端终端)从K_{NR_U2U_ProSe}衍生得到的256位密钥，用于衍生保护终端间特定U2U中继业务的通信会话的密钥。K_U2U-sess与TS 33.536中规定的K_NRP-sess相同，按单播链路衍生。在终端间激活的单播通信会话中，K_U2U-sess可以通过运行密钥更新过程来刷新。That is: K_U2U-sess : a 256-bit key derived by the UE (relay terminal and/or remote terminal) from K_{NR_U2U_ProSe} , which is used to derive the key for protecting the communication session of a specific U2U relay service between terminals. K_U2U-sess is the same as K_NRP-sess specified in TS 33.536, and is derived from unicast links. In an active unicast communication session between endpoints, K_U2U-sess can be refreshed by running a key update process.

7、K_U2U-inc、K_U2U-enc7. K_U2U-inc , K_U2U-enc

K_U2U-inc,K_U2U-enc:The K_U2U-inc and K_U2U-enc are used in the chosen confidentiality and integrity algorithms respectively for protecting the integrity and confidentiality of PC5-S signalling,PC5 RRC signalling,and PC5 user plane data.These keys are equivalent to NRPIK and NRPEK as specified in TS 33.536.They are derived from K_U2U-sess and are refreshed automatically every time K_U2U-sess is changed.K_U2U-inc ,K_U2U-enc :The K_U2U-inc and K_U2U-enc are used in the chosen confidentiality and integrity algorithms respectively for protecting the integrity and confidentiality of PC5-S signaling, PC5 RRC signaling, and PC5 user plane data.These keys are equivalent to NRPIK and NRPEK as specified in TS 33.536.They are derived from K_U2U-sess and are refreshed automatically every time K_U2U-sess is changed.

即：K_U2U-inc、K_U2U-enc：为加密算法和完整性算法的密钥，用于保护PC5-s信令、PC5RRC信令和PC5用户面数据的完整性和机密性。K_U2U-inc、K_U2U-enc等价于TS 33.536中指定的NRPIK和NRPEK。K_U2U-inc、K_U2U-enc由K_U2U-sess衍生得到，每次K_U2U-sess更新时K_U2U-inc、K_U2U-enc自动更新。That is: K_U2U-inc , K_U2U-enc : are the keys of the encryption algorithm and integrity algorithm, used to protect the integrity and confidentiality of PC5-s signaling, PC5RRC signaling and PC5 user plane data. K_U2U-inc and K_U2U-enc are equivalent to NRPIK and NRPEK specified in TS 33.536. K_U2U-inc and K_U2U-enc are derived from K_U2U-sess . K_U2U-inc and K_U2U-enc are automatically updated every time K_U2U-sess is updated.

二、5GPRUK、5GPRUK ID、K_{NR_U2N_ProSe}、K_{NR_U2U_Prose}的衍生函数：2. Derivative functions of 5GPRUK, 5GPRUK ID, K_{NR_U2N_ProSe} and K_{NR_U2U_Prose} :

1、5GPRUK1.5GPRUK

When deriving a 5GPRUK from K_{AUSF_G},the following parameters shall be used to form the input S to the KDF.即：从K_{AUSF_G}衍生到5GPRUK时，应使用以下参数作为KDF的输入S:When deriving a 5GPRUK from K_{AUSF_G} , the following parameters shall be used to form the input S to the KDF. That is: when deriving from K_{AUSF_G} to 5GPRUK, the following parameters shall be used to form the input S to the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Service indicator(e.g.0x01 for ProSe service；0x02 for Ranging service)，即P0是本申请中5GPRUK的衍生函数的第1个输入参数；- P0=Service indicator (e.g.0x01 for ProSe service; 0x02 for Ranging service), that is, P0 is the first input parameter of the derived function of 5GPRUK in this application;

- L0＝length of Service indicator，即L0是本申请中5GPRUK的衍生函数的业务指示符的长度；- L0=length of Service indicator, that is, L0 is the length of the service indicator of the derivative function of 5GPRUK in this application;

- P1＝SUPI(Subscription PermanentIdentifier，用户永久标识符)，即P1是本申请中5GPRUK的衍生函数的第2个输入参数；- P1=SUPI (Subscription PermanentIdentifier, user permanent identifier), that is, P1 is the second input parameter of the derivative function of 5GPRUK in this application;

- L1＝length of SUPI，即L1是本申请中5GPRUK的衍生函数的SUPI的长度。- L1=length of SUPI, that is, L1 is the length of SUPI of the derivative function of 5GPRUK in this application.

The input key KEY is K_{AUSF_G}，即：输入密钥为K_{AUSF_G}。The input key KEY is K_{AUSF_G} , that is: the input key is K_{AUSF_G} .

2、5GPRUK ID2. 5GPRUK ID

When deriving the 5GPRUK ID from K_{AUSF_G},the following parameters are used to form the input S to the KDF.即：从K_{AUSF_G}衍生到5GPRUK ID时，应使用以下参数作为KDF的输入S:When deriving the 5GPRUK ID from K_{AUSF_G} , the following parameters are used to form the input S to the KDF. That is: when deriving from K_{AUSF_G} to 5GPRUK ID, the following parameters should be used as the input S of the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Key ID string(e.g."PRUK-ID"for ProSe service,“RRUK-ID”for Ranging service)，即P0是5GPRUK ID的衍生函数的第1个输入参数；- P0＝Key ID string (e.g. "PRUK-ID" for ProSe service, "RRUK-ID" for Ranging service), that is, P0 is the first input parameter of the derivative function of 5GPRUK ID;

- L0＝length of key ID string，即L0是5GPRUK ID的衍生函数的密钥标识字符串的长度.- L0=length of key ID string, that is, L0 is the length of the key identification string of the derivative function of 5GPRUK ID.

- P1＝SUPI，即P1是5GPRUK ID的衍生函数的第2个输入参数；- P1=SUPI, that is, P1 is the second input parameter of the derivative function of 5GPRUK ID;

- L1＝length of SUPI，即L1是5GPRUK ID的衍生函数的SUPI的长度。- L1=length of SUPI, that is, L1 is the length of SUPI of the derivative function of 5GPRUK ID.

The input key KEY is K_{AUSF_G}，即：输入密钥为K_{AUSF_G}。The input key KEY is K_{AUSF_G} , that is: the input key is K_{AUSF_G} .

3、K_{NR_U2N_ProSe}3. K_{NR_U2N_ProSe}

When deriving a K_{NR_U2N_Prose} from 5GPRUK,the following parameters shall be used to form the input S to the KDF，即：从5GPRUK衍生到K_{NR_U2N_Prose}时，应使用以下参数作为KDF的输入S:When deriving_a K_{NR_U2N_Prose} from 5GPRUK, the following parameters shall be used to form the input S to the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Nonce_2，即P0是K_{NR_U2N_ProSe}的衍生函数的第1个输入参数；- P0=Nonce_2, that is, P0 is the first input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L0＝length of Nonce_2，即L0是K_{NR_U2N_ProSe}的衍生函数的随机数2的长度；- L0=length of Nonce_2, that is, L0 is the length of the random number 2 of the derivative function of K_{NR_U2N_ProSe} ;

- P1＝Nonce_1，即P1是K_{NR_U2N_ProSe}的衍生函数的第2个输入参数；- P1=Nonce_1, that is, P1 is the second input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L1＝length of Nonce_1，即L1是K_{NR_U2N_ProSe}的衍生函数的随机数1的长度；- L1=length of Nonce_1, that is, L1 is the length of the random number 1 of the derivative function of K_{NR_U2N_ProSe} ;

- P2＝Relay service code，即P2是K_{NR_U2N_ProSe}的衍生函数的第3个输入参数；- P2＝Relay service code, that is, P2 is the third input parameter of the derivative function of K_{NR_U2N_ProSe} ;

- L2＝length of Relay service code，即L2是K_{NR_U2N_ProSe}的衍生函数的中继业务代码的长度。- L2=length of Relay service code, that is, L2 is the length of the relay service code of the derivative function of K_{NR_U2N_ProSe} .

The input key KEY is 5GPRUK，即：输入密钥为5GPRUK。The input key KEY is 5GPRUK, that is: the input key is 5GPRUK.

4、K_{NR_U2U_Prose}4. K_{NR_U2U_Prose}

When deriving a K_{NR_U2U_Prose} from 5GPRUK,the following parameters shall be used to form the input S to the KDF，即：从5GPRUK衍生到K_{NR_U2U_Prose}时，应使用以下参数作为KDF的输入S:When deriving_a K_{NR_U2U_Prose} from 5GPRUK, the following parameters shall be used to form the input S to the KDF:

- FC＝TBD(to be allocated by 3GPP)；- FC=TBD (to be allocated by 3GPP);

- P0＝Nonce_2，即P0是K_{NR_U2U_Prose}的衍生函数的第1个输入参数；- P0=Nonce_2, that is, P0 is the first input parameter of the derivative function of K_{NR_U2U_Prose} ;

- L0＝length of Nonce_2，即L0是K_{NR_U2U_Prose}的衍生函数的随机数2的长度；- L0=length of Nonce_2, that is, L0 is the length of the random number 2 of the derivative function of K_{NR_U2U_Prose} ;

- P1＝Nonce_1，即P1是K_{NR_U2U_Prose}的衍生函数的第2个输入参数；- P1=Nonce_1, that is, P1 is the second input parameter of the derivative function of K_{NR_U2U_Prose} ;

- L1＝length of Nonce_1，即L1是K_{NR_U2U_Prose}的衍生函数的随机数1的长度；- L1＝length of Nonce_1, that is, L1 is the length of the random number 1 of the derivative function of K_{NR_U2U_Prose} ;

- P2＝Prose U2U service code，即：Prose U2U业务代码，P2是K_{NR_U2U_Prose}的衍生函数的第3个输入参数；- P2＝Prose U2U service code, that is: Prose U2U service code, P2 is the third input parameter of the derivative function of K_{NR_U2U_Prose} ;

- L2＝length of Prose U2U service code，即：Prose U2U业务代码的长度，L2是K_{NR_U2U_Prose}的衍生函数的Prose U2U业务代码的长度。- L2＝length of Prose U2U service code, that is: the length of Prose U2U service code, L2 is the length of Prose U2U service code of the derivative function of K_{NR_U2U_Prose} .

The input key KEY is 5GPRUK，即：输入密钥为5GPRUK。The input key KEY is 5GPRUK, that is: the input key is 5GPRUK.

图6示出了本申请一个示例性实施例提供的邻近通信业务的密钥生成方法的流程图。该邻近通信业务的密钥生成方法可以由核心网设备来执行。该方法包括：Figure 6 shows a flow chart of a key generation method for proximity communication services provided by an exemplary embodiment of the present application. The key generation method for the proximity communication service may be executed by the core network device. The method includes:

步骤210：基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，第一密钥为使用邻近通信业务的实体的PC5根密钥，第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。Step 210: Derive the second key of the user plane and the control plane based on the first key in the same derivation method. The first key is the PC5 root key of the entity using the proximity communication service, and the second key is the PC5 root key of the entity using the proximity communication service. Relay service root key between two entities communicating over a broadcast link.

第一密钥为使用ProSe的终端的PC5接口的根密钥。第一密钥可以标为PRUK、5GPRUK。The first key is the root key of the PC5 interface of the terminal using ProSe. The first key can be labeled PRUK, 5GPRUK.

第二密钥为使用PC5单播链路进行通信的远端终端和中继终端的中继业务根密钥。针对不同的中继业务，第二密钥可为U2N中继业务对应的第一子密钥和/或U2U中继业务对应的第二子密钥。第一子密钥为使用PC5单播链路进行通信的两个实体间的U2N中继业务根密钥。第二子密钥为使用PC5单播链路进行通信的两个实体间的U2U中继业务根密钥。The second key is the relay service root key of the remote terminal and the relay terminal that communicate using the PC5 unicast link. For different relay services, the second key may be a first subkey corresponding to the U2N relay service and/or a second subkey corresponding to the U2U relay service. The first subkey is the U2N relay service root key between two entities communicating using the PC5 unicast link. The second subkey is the U2U relay service root key between two entities communicating using the PC5 unicast link.

本申请实施例中，在用户面和控制面上，用第一密钥衍生得到第二密钥的衍生方式是相同的。即，在用户面和控制面，从第一密钥衍生得到第二密钥的衍生函数的输入都是：与业务相关的代码(例如：中继业务代码或ProSe U2U业务代码)、与业务相关的代码的长度、FC(Function Code，功能代码)、随机数1、随机数1的长度、随机数2、随机数2的长度。In the embodiment of the present application, the derivation method of using the first key to derive the second key is the same on the user plane and the control plane. That is, on the user plane and the control plane, the inputs of the derivation function that derives the second key from the first key are: service-related codes (for example: relay service code or ProSe U2U service code), service-related The length of the code, FC (Function Code, function code), random number 1, the length of random number 1, random number 2, and the length of random number 2.

示例性的，针对同一中继业务，在用户面/控制面使用第一密钥衍生得到第二密钥的衍生方式是相同的。针对不同中继业务，基于第一密钥衍生得到第二密钥的衍生方式不同。例如，第一子密钥与第一U2N中继业务绑定，第二子密钥与第一ProSe U2U业务绑定，则得到第一子密钥和第二子密钥其衍生函数的输入不同。For example, for the same relay service, the derivation method of using the first key to derive the second key on the user plane/control plane is the same. For different relay services, the derivation methods for obtaining the second key based on the first key are different. For example, if the first subkey is bound to the first U2N relay service and the second subkey is bound to the first ProSe U2U service, then the inputs of the derivative functions of the first subkey and the second subkey are different. .

例如，针对U2N中继业务，从第一密钥得到第一子密钥的KDF的输入包括：第一U2N中继业务的中继业务代码、中继业务代码的长度。衍生函数的输入密钥为第一密钥。For example, for the U2N relay service, the input of the KDF for obtaining the first subkey from the first key includes: the relay service code of the first U2N relay service and the length of the relay service code. The input key to the derivative function is the first key.

针对U2U中继业务，从第一密钥得到第二子密钥的KDF的输入包括：第一ProSe U2U业务的ProSe U2U业务代码、所述ProSe U2U业务代码的长度。衍生函数的输入密钥为第一密钥。For the U2U relay service, the input of the KDF for obtaining the second subkey from the first key includes: the ProSe U2U service code of the first ProSe U2U service and the length of the ProSe U2U service code. The input key to the derivative function is the first key.

在U2N中继业务中，核心网网元在生成第一子密钥后，向中继终端发送第一子密钥。在U2U中继业务中，可以由核心网网元向中继终端发送第二子密钥。也可以为中继终端与远端终端共同协商生成第二子密钥。In the U2N relay service, after generating the first subkey, the core network element sends the first subkey to the relay terminal. In the U2U relay service, the core network element can send the second subkey to the relay terminal. The relay terminal and the remote terminal may also negotiate together to generate the second subkey.

示例性的，用户面的第二密钥是指：由核心网设备的用户面网元基于第一密钥衍生得到的第二密钥。用户面网元包括：PKMF网元或其他新的用户面网元。For example, the second key of the user plane refers to a second key derived by the user plane network element of the core network device based on the first key. User plane network elements include: PKMF network elements or other new user plane network elements.

控制面的第二密钥是指：由核心网设备的控制面网元基于第一密钥衍生得到的第二密钥。控制面网元包括：AUSF网元或PAnF网元或其他新的控制面网元。The second key of the control plane refers to the second key derived by the control plane network element of the core network device based on the first key. Control plane network elements include: AUSF network elements or PAnF network elements or other new control plane network elements.

综上所述，本实施例提供的方法，通过基于第一密钥使用相同的衍生方式衍生得到用户面和控制面的第二密钥，使用户面和控制面的密钥层次结构相统一，简化ProSe的密钥层次结构，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided by this embodiment uses the same derivation method based on the first key to derive the second keys of the user plane and the control plane, so as to unify the key hierarchies of the user plane and the control plane. Simplifying ProSe's key hierarchy reduces the burden on core network equipment and terminal equipment to perform ProSe security processes.

图7示出了本申请一个示例性实施例提供的邻近通信业务的密钥生成方法的流程图。该邻近通信业务的密钥生成方法可以由远端终端来执行。该方法包括：Figure 7 shows a flow chart of a key generation method for proximity communication services provided by an exemplary embodiment of the present application. The key generation method for the proximity communication service may be executed by the remote terminal. The method includes:

步骤310：基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，第一密钥为使用邻近通信业务的实体的PC5根密钥，第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。Step 310: Derive the second key of the user plane and the control plane based on the first key in the same derivation method. The first key is the PC5 root key of the entity using the proximity communication service, and the second key is the PC5 root key of the entity using the proximity communication service. Relay service root key between two entities communicating over a broadcast link.

远端终端使用控制面的衍生方式，基于第一密钥得到第二密钥。或，远端终端使用用户面的衍生方式，基于第一密钥得到第二密钥。其中，用户面衍生方式与控制面衍生方式为同种衍生方式。基于第一密钥得到第二密钥的衍生方式与核心网设备侧的衍生方式相同。The remote terminal uses the control plane derivation method to obtain the second key based on the first key. Or, the remote terminal uses a user plane derivation method to obtain the second key based on the first key. Among them, the user plane derivation method and the control plane derivation method are the same derivation methods. The derivation method of obtaining the second key based on the first key is the same as the derivation method on the core network device side.

在U2U中继业务中，远端终端可以与中继终端共同协商得到第二子密钥，也可以接收核心网网元发送的第二子密钥。In the U2U relay service, the remote terminal can negotiate with the relay terminal to obtain the second subkey, or can receive the second subkey sent by the core network element.

综上所述，本实施例提供的方法，通过基于第一密钥使用相同的衍生方式衍生得到用户面和控制面的第二密钥，使用户面和控制面的密钥层次结构相统一，简化ProSe的密钥层次结构，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided by this embodiment uses the same derivation method based on the first key to derive the second keys of the user plane and the control plane, so as to unify the key hierarchies of the user plane and the control plane. Simplifying ProSe's key hierarchy reduces the burden on core network equipment and terminal equipment to perform ProSe security processes.

图8示出了本申请一个示例性实施例提供的邻近通信业务的密钥生成方法的流程图。该邻近通信业务的密钥生成方法可以由中继终端来执行。该方法包括：Figure 8 shows a flow chart of a key generation method for proximity communication services provided by an exemplary embodiment of the present application. The key generation method for the proximity communication service may be performed by the relay terminal. The method includes:

步骤410：获取第二密钥，第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，第一密钥为使用邻近通信业务的实体的PC5根密钥，第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。Step 410: Obtain the second key. The second key is the key of the user plane and/or the control plane derived in the same derivation method based on the first key. The first key is the PC5 of the entity using the proximity communication service. The root key, the second key is the root key of the relay service between two entities communicating using the PC5 unicast link.

在U2N中继业务中，中继终端不执行从第一密钥到第二密钥的衍生。第一密钥到第二密钥的衍生由核心网设备或远端终端执行，中继终端接收核心网设备发送的第二密钥。In the U2N relay service, the relay terminal does not perform derivation from the first key to the second key. The derivation of the first key to the second key is performed by the core network device or the remote terminal, and the relay terminal receives the second key sent by the core network device.

第二密钥是由核心网设备基于第一密钥衍生得到的用户面和/或控制面的密钥。The second key is a user plane and/or control plane key derived by the core network device based on the first key.

在U2U中继业务中，中继终端可以接收核心网设备发送的第二密钥；或者，中继终端可以与远端终端协商生成第二密钥；或者，中继终端基于第一密钥衍生得到第二密钥。In the U2U relay service, the relay terminal can receive the second key sent by the core network device; or the relay terminal can negotiate with the remote terminal to generate the second key; or the relay terminal can derive the second key based on the first key. Get the second key.

综上所述，本实施例提供的方法，通过基于第一密钥使用相同的衍生方式衍生得到用户面和控制面的第二密钥，使用户面和控制面的密钥层次结构相统一，简化ProSe的密钥层次 结构，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided by this embodiment uses the same derivation method based on the first key to derive the second keys of the user plane and the control plane, so as to unify the key hierarchies of the user plane and the control plane. Simplifying ProSe's key hierarchy reduces the burden on core network equipment and terminal equipment to perform ProSe security processes.

在一种可选的实施例中，可以在U2N中继业务中应用本申请提供的邻近通信业务的密钥生成方法。In an optional embodiment, the key generation method for the proximity communication service provided by this application can be applied to the U2N relay service.

图9是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图9所示，该方法可以由远端终端、中继终端、核心网网元中继终端来执行。该方法包括：Figure 9 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 9, this method can be executed by a remote terminal, a relay terminal, or a core network element relay terminal. The method includes:

步骤201：远端终端与核心网网元进行第一业务的身份认证，得到第三密钥(例如，K_{AUSF_G})。Step 201: The remote terminal performs identity authentication on the first service with the core network element, and obtains the third key (for example, K_{AUSF_G} ).

第一业务为特定业务。第一业务是除需要进行主身份认证之外还需要额外进行身份认证的业务。例如，第一业务包括以下至少一项：邻近通信业务(ProSe)、测距业务(Ranging service)。The first business is a specific business. The first business is a business that requires additional identity authentication in addition to the main identity authentication. For example, the first service includes at least one of the following: proximity communication service (ProSe) and ranging service (Ranging service).

第三密钥为通过第一业务的身份认证生成的中间密钥。通过第一业务的身份认证，得到第三密钥。第三密钥可以标为K_{AUSF_G}，也可以标为其他名称，例如，K_G、K_{AUSF_A}、K_{AUSF_B}、Ks(_ext)_NAF。第三密钥与K_AUSF不同，K_AUSF为运行主身份认证得到的密钥，例如在终端设备接入网络时进行身份认证得到的密钥。而第三密钥是在获取某项业务前，针对该项业务额外进行的一次身份认证过程中得到的密钥。The third key is an intermediate key generated through identity authentication of the first service. Through the identity authentication of the first business, the third key is obtained. The third key may be labeled K_{AUSF_G} or may be labeled with other names, for example, K_G , K_{AUSF_A} , K_{AUSF_B} , Ks(_ext)_NAF. The third key is different from K_AUSF . K_AUSF is the key obtained by running primary identity authentication, for example, the key obtained by identity authentication when the terminal device accesses the network. The third key is a key obtained during an additional identity authentication process for a certain service before obtaining the service.

在使用控制面生成密钥时，由控制面网元使用第三密钥衍生得到第一密钥。When the control plane is used to generate the key, the control plane network element uses the third key to derive the first key.

在使用用户面生成密钥时，由用户面网元生成得到第一密钥。When the user plane is used to generate the key, the first key is generated by the user plane network element.

示例性的，在远端终端与核心网网元执行身份认证前，确定使用控制面或用户面生成密钥。例如，由核心网设备确定使用控制面或用户面生成密钥。再如，在发起第一业务时，根据第一业务的要求确定使用用户面或控制面生成密钥，例如，远端终端根据第一业务的要求，向用户面核心网网元(用户面网元)或控制面核心网网元(控制面网元)发起认证。用户面核心网网元或控制面核心网网元与远端终端交互认证消息，生成对应平面的密钥。For example, before the remote terminal performs identity authentication with the core network element, it is determined to use the control plane or the user plane to generate a key. For example, it is up to the core network device to determine whether to use the control plane or the user plane to generate the key. For another example, when initiating the first service, it is determined to use the user plane or the control plane to generate a key according to the requirements of the first service. For example, the remote terminal sends a message to the user plane core network element (user plane network) according to the requirements of the first service. The authentication is initiated by the control plane core network element (control plane network element) or the control plane core network element (control plane network element). The user plane core network element or the control plane core network element exchanges authentication messages with the remote terminal to generate a key for the corresponding plane.

步骤202：远端终端基于第三密钥获取第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。核心网网元基于第三密钥获取第一密钥(例如，PRUK)和第一密钥标识。Step 202: The remote terminal obtains the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key. The core network element obtains the first key (for example, PRUK) and the first key identification based on the third key.

第一密钥是安全建立PC5单播链路的根凭证。第一密钥可以标为PRUK或5GPRUK。基于第三密钥得到第一密钥的衍生函数的输入包括以下至少一项：FC、第一业务的业务指示符(Service indicator)、业务指示符的长度、SUPI、SUPI的长度。示例性的，在U2N中继业务中，SUPI为远端终端的SUPI；在U2U中继业务中，SUPI为远端终端或中继终端的SUPI。业务指示符为第一业务对应的业务指示符，例如，业务指示符为0x01表示ProSe业务(第一业务)；业务指示符为0x02表示测距业务(第一业务)。The first key is the root credential for securely establishing PC5 unicast links. The first key can be labeled PRUK or 5GPRUK. The input of the derivative function for obtaining the first key based on the third key includes at least one of the following: FC, a service indicator (Service indicator) of the first service, the length of the service indicator, SUPI, and the length of the SUPI. For example, in the U2N relay service, the SUPI is the SUPI of the remote terminal; in the U2U relay service, the SUPI is the SUPI of the remote terminal or the relay terminal. The service indicator is a service indicator corresponding to the first service. For example, the service indicator is 0x01, which represents the ProSe service (the first service); the service indicator is 0x02, which represents the ranging service (the first service).

在U2N中继业务中，使用控制面生成密钥的情况下，控制面的核心网网元和远端终端各自基于第一业务身份认证中的第三密钥获取到第一密钥。控制面的核心网网元可以包括AUSF、PAnF或其他新的控制面网元。In the U2N relay service, when the control plane is used to generate keys, the core network element of the control plane and the remote terminal each obtain the first key based on the third key in the first service identity authentication. The core network elements of the control plane may include AUSF, PAnF or other new control plane elements.

在U2N中继业务中，使用用户面生成密钥的情况下，用户面的核心网网元和远端终端各自基于第一业务身份认证中的第三密钥获取到第一密钥。用户面的核心网网元可以包括PKMF或其他新的用户面网元。In the U2N relay service, when the user plane is used to generate keys, the core network element and the remote terminal of the user plane each obtain the first key based on the third key in the first service identity authentication. The core network elements of the user plane may include PKMF or other new user plane network elements.

示例性的，在U2N中继业务中，远端终端和核心网网元各自基于第三密钥获取到第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。For example, in the U2N relay service, the remote terminal and the core network element each obtain the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key.

第一密钥标识用于标识第一密钥。在控制面中，第一密钥标识由第三密钥衍生得到。在基于第三密钥衍生得到第一密钥标识的情况下，KDF的输入包括以下至少一项：第一密钥标识字符串(Key ID string)、第一密钥标识字符串的长度、SUPI、SUPI的长度。第一密钥标识字符串与第一密钥的业务对应。例如，密钥标识字符串“PRUK-ID”表示ProSe业务(第一业务)，密钥标识字符串“RRUK-ID”表示测距业务(第一业务)。The first key identifier is used to identify the first key. In the control plane, the first key identification is derived from the third key. In the case where the first key identification is derived based on the third key, the input of the KDF includes at least one of the following: the first key identification string (Key ID string), the length of the first key identification string, SUPI , the length of SUPI. The first key identification string corresponds to the service of the first key. For example, the key identification string "PRUK-ID" represents the ProSe service (first service), and the key identification string "RRUK-ID" represents the ranging service (first service).

步骤203：远端终端基于第一密钥衍生得到第一子密钥(例如，K_{NR_U2N_ProSe})；核心网 网元基于第一密钥衍生得到第一子密钥(例如，K_{NR_U2N_ProSe})。Step 203: The remote terminal derives the first subkey (for example, K_{NR_U2N_ProSe} ) based on the first key; the core network element derives the first subkey (for example, K_{NR_U2N_ProSe} ) based on the first key.

第一子密钥为使用单播链路进行通信的中继终端和远端终端间的中继业务根密钥。第一子密钥为与特定U2N中继业务(第一U2N中继业务)绑定的中继业务根密钥。其长度可以为256位。第一子密钥用于在中继终端和远端终端间建立安全的单播链路。第一子密钥对应中继终端和远端终端。The first subkey is the relay service root key between the relay terminal and the remote terminal that communicate using the unicast link. The first subkey is a relay service root key bound to a specific U2N relay service (first U2N relay service). Its length can be 256 bits. The first subkey is used to establish a secure unicast link between the relay terminal and the remote terminal. The first subkey corresponds to the relay terminal and the remote terminal.

第一子密钥与第一U2N中继业务绑定；在基于第一密钥衍生得到第一子密钥的情况下，KDF的输入包括以下至少一项：第一U2N中继业务的中继业务代码(Relay service code)、中继业务代码的长度、随机数1、随机数1的长度、随机数2、随机数2的长度。其中，中继业务代码即为TS 33.503中PRUK衍生函数的输入“Relay service code”。The first subkey is bound to the first U2N relay service; when the first subkey is derived based on the first key, the input of the KDF includes at least one of the following: Relay of the first U2N relay service Service code (Relay service code), length of relay service code, random number 1, length of random number 1, random number 2, length of random number 2. Among them, the relay service code is the input "Relay service code" of the PRUK derivative function in TS 33.503.

步骤204：核心网网元向中继终端发送第一子密钥(例如，K_{NR_U2N_ProSe})。Step 204: The core network element sends the first subkey (for example, K_{NR_U2N_ProSe} ) to the relay terminal.

核心网网元在使用第一密钥衍生得到第一子密钥后，向U2N中继终端发送第一子密钥。使中继终端使用第一子密钥与远端终端建立安全的单播链路。After using the first key to derive the first subkey, the core network element sends the first subkey to the U2N relay terminal. The relay terminal uses the first subkey to establish a secure unicast link with the remote terminal.

步骤205：远端终端基于第一子密钥衍生得到第一会话密钥(例如，K_relay-sess)；中继终端基于第一子密钥衍生得到第一会话密钥(例如，K_relay-sess)。Step 205: The remote terminal derives the first session key (for example, K_relay-sess ) based on the first subkey; the relay terminal derives the first session key (for example, K_relay- sess) based on the first subkey._sess ).

步骤206：远端终端基于第一会话密钥(例如，K_relay-sess)衍生得到第一加密密钥(例如，K_relay-enc)和/或第一完整性密钥(例如，K_relay-inc)；中继终端基于第一会话密钥(例如，K_relay-sess)衍生得到第一加密密钥(例如，K_relay-enc)和/或第一完整性密钥(例如，K_relay-inc)。Step 206: The remote terminal derives the first encryption key (for example, K_{relay-enc) and/or the first integrity key (for example, K relay-} sess) based on the first session key (for example, K_{relay-sess) inc} ); the relay terminal derives the first encryption key (for example, K relay_-enc ) and/or the first integrity key (for example, K_relay-inc ).

基于第一会话密钥衍生得到第一完整性密钥的方法可以参考TS33.503中所提供的方法。第一加密密钥等价于TS 33.536中的NRPEK；第一完整性密钥等价于TS 33.536中的NRPIK。For a method of deriving the first integrity key based on the first session key, refer to the method provided in TS33.503. The first encryption key is equivalent to NRPEK in TS 33.536; the first integrity key is equivalent to NRPIK in TS 33.536.

步骤207：远端终端与中继终端使用第一加密密钥和第一完整性密钥进行通信。Step 207: The remote terminal and the relay terminal communicate using the first encryption key and the first integrity key.

图9所示的流程图为在U2N中继业务中由控制面或用户面生成密钥的方法流程图。在控制面中，核心网网元可以为AUSF或PAnF或其他新的控制面网元。在用户面中，核心网网元可以为PKMF或其他新的用户面网元。The flow chart shown in Figure 9 is a flow chart of a method for generating keys from the control plane or the user plane in the U2N relay service. In the control plane, the core network elements can be AUSF or PAnF or other new control plane elements. In the user plane, the core network elements can be PKMF or other new user plane elements.

在一种可选的实施例中，对于用户面，图9所示的实施例仅为一种用户面网元生成密钥的方法，如图10所示，在另一种使用用户面生成密钥的情况下，则不需要使用基于第三密钥衍生得到第一密钥的衍生函数，直接使用第三密钥充当第一密钥。用户面的核心网网元可以包括PKMF或其他新的用户面网元。In an optional embodiment, for the user plane, the embodiment shown in Figure 9 is only a method for user plane network elements to generate keys. As shown in Figure 10, in another method for using the user plane to generate keys, In the case of a key, there is no need to use a derivation function based on the third key to derive the first key, and the third key can be directly used as the first key. The core network elements of the user plane may include PKMF or other new user plane network elements.

可选地，图10给出了另一种在U2N中继业务中由用户面生成密钥的方法流程图，与图9不同的是，由用户面生成第一密钥时，是由用户面的核心网网元直接生成第三密钥，将第三密钥当做第一密钥使用。Optionally, Figure 10 shows a flow chart of another method for generating a key by the user plane in the U2N relay service. The difference from Figure 9 is that when the first key is generated by the user plane, the user plane The core network element directly generates the third key and uses the third key as the first key.

如图10所示，步骤202替换为步骤202a和步骤202b：由用户面的核心网网元生成第三密钥，然后核心网网元和远端终端获取得到PRUK和PRUK ID。As shown in Figure 10, step 202 is replaced with step 202a and step 202b: the core network element on the user plane generates a third key, and then the core network element and the remote terminal obtain PRUK and PRUK ID.

综上，在U2N中继业务中，在控制面下，由远端终端和核心网网元执行特定业务的业务认证，得到第三密钥，使用第三密钥衍生得到第一密钥，使用第一密钥衍生得到第一子密钥。核心网网元将第一子密钥发送给中继终端。远端终端和中继终端使用第一子密钥衍生得到第一会话密钥，使用第一会话密钥衍生得到第一加密密钥和第一完整性密钥。In summary, in the U2N relay service, under the control plane, the remote terminal and the core network element perform service authentication for a specific service to obtain the third key. The third key is used to derive the first key. Use The first key is derived to obtain the first subkey. The core network element sends the first subkey to the relay terminal. The remote terminal and the relay terminal use the first subkey to derive the first session key, and use the first session key to derive the first encryption key and the first integrity key.

在U2N中继业务中，在用户面下，核心网网元可以使用衍生函数，基于第三密钥生成第一密钥，也可以将生成的第三密钥，当做第一密钥进行使用。远端终端/核心网网元使用第一密钥衍生得到第一子密钥。核心网网元将第一子密钥发送给中继终端。远端终端/中继终端使用第一子密钥衍生得到第一会话密钥，使用第一会话密钥衍生得到第一加密密钥和第一完整性密钥。In the U2N relay service, under the user plane, the core network element can use the derivative function to generate the first key based on the third key, or the generated third key can be used as the first key. The remote terminal/core network element uses the first key to derive the first subkey. The core network element sends the first subkey to the relay terminal. The remote terminal/relay terminal uses the first subkey to derive the first session key, and uses the first session key to derive the first encryption key and the first integrity key.

综上所述，本实施例提供的方法，通过使用特定业务身份认证得到的第三密钥(例如，K_{AUSF_G})，来衍生得到第一密钥(例如，5GPRUK)，简化了ProSe的密钥层次结构，使控制 面和用户面的密钥层次结构相统一，降低了密钥层次结构的复杂度，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided in this embodiment uses the third key (for example, K_{AUSF_G} ) obtained by specific business identity authentication to derive the first key (for example, 5GPRUK), which simplifies the ProSe key. The hierarchical structure unifies the key hierarchies of the control plane and the user plane, reduces the complexity of the key hierarchical structure, and reduces the burden of core network equipment and terminal equipment in executing the ProSe security process.

在一种可选的实施例中，可以在U2U中继业务中应用本申请提供的邻近通信业务的密钥生成方法。In an optional embodiment, the key generation method for the proximity communication service provided by this application can be applied to the U2U relay service.

在U2U中继业务中，第二子密钥的生成可以包括如下四种情况：In the U2U relay service, the generation of the second subkey may include the following four situations:

情况1：中继终端接收核心网设备发送的第二子密钥。Case 1: The relay terminal receives the second subkey sent by the core network device.

由远端终端与核心网设备执行第一业务的身份认证，核心网设备和远端终端分别基于身份认证的第三密钥获取第一密钥，基于第一密钥衍生得到第二子密钥。核心网设备向中继终端发送第二子密钥。The remote terminal and the core network device perform identity authentication for the first service. The core network device and the remote terminal respectively obtain the first key based on the third key of the identity authentication, and derive the second subkey based on the first key. . The core network device sends the second subkey to the relay terminal.

情况2：远端终端接收核心网设备发送的第二子密钥。Case 2: The remote terminal receives the second subkey sent by the core network device.

由中继终端与核心网设备执行第一业务的身份认证，核心网设备和中继终端分别基于身份认证的第三密钥获取第一密钥，基于第一密钥衍生得到第二子密钥。核心网设备向远端终端发送第二子密钥。The relay terminal and the core network device perform identity authentication for the first service. The core network device and the relay terminal respectively obtain the first key based on the third key of the identity authentication, and derive the second subkey based on the first key. . The core network device sends the second subkey to the remote terminal.

情况3：远端终端和中继终端根据预置信息获取第一密钥，远端终端与中继终端共同协商生成第二子密钥。Case 3: The remote terminal and the relay terminal obtain the first key according to the preset information, and the remote terminal and the relay terminal jointly negotiate to generate the second subkey.

远端终端与中继终端根据预置信息获取第一密钥。远端终端与中继终端协商第二子密钥的生成参数，远端终端与中继终端根据协商结果各自基于第一密钥衍生得到第二子密钥。The remote terminal and the relay terminal obtain the first key according to the preset information. The remote terminal and the relay terminal negotiate the generation parameters of the second subkey, and the remote terminal and the relay terminal each derive the second subkey based on the first key according to the negotiation result.

情况4：远端终端根据预置信息获取第一密钥，中继终端从核心网设备获取第一密钥，远端终端与中继终端共同协商生成第二子密钥。Case 4: The remote terminal obtains the first key according to the preset information, the relay terminal obtains the first key from the core network device, and the remote terminal and the relay terminal jointly negotiate to generate the second subkey.

远端终端根据预置信息获取第一密钥。中继终端从核心网设备获取第一密钥。远端终端与中继终端协商第二子密钥的生成参数，远端终端与中继终端根据协商结果各自基于第一密钥衍生得到第二子密钥。The remote terminal obtains the first key according to the preset information. The relay terminal obtains the first key from the core network device. The remote terminal and the relay terminal negotiate the generation parameters of the second subkey, and the remote terminal and the relay terminal each derive the second subkey based on the first key according to the negotiation result.

针对情况1：For case 1:

图11是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图11所示，该方法可以由远端终端、中继终端、核心网网元来执行。该方法包括：Figure 11 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 11, this method can be executed by remote terminals, relay terminals, and core network elements. The method includes:

步骤301-11：远端终端与核心网网元进行第一业务的身份认证，得到第三密钥(例如，K_{AUSF_G})。Step 301-11: The remote terminal performs identity authentication on the first service with the core network element, and obtains the third key (for example, K_{AUSF_G} ).

其中，核心网网元可以是控制面网元，也可以是用户面网元。即，核心网网元可以是：AUSF、PAnF、PKMF、新的用户面网元或新的控制面网元。Among them, the core network element can be a control plane network element or a user plane network element. That is, the core network element can be: AUSF, PAnF, PKMF, a new user plane network element or a new control plane network element.

步骤301-12：远端终端基于第三密钥获取到第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。核心网网元基于第三密钥获取第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。Step 301-12: The remote terminal obtains the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key. The core network element obtains the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key.

第一密钥是安全建立PC5单播链路的根凭证。The first key is the root credential for securely establishing PC5 unicast links.

针对情况1和情况2，基于第三密钥获取第一密钥的方式有两种：For situations 1 and 2, there are two ways to obtain the first key based on the third key:

方式1：基于第三密钥得到第一密钥可以使用衍生函数。如果使用衍生函数，则衍生函数的输入包括以下至少一项：FC、第一业务的业务指示符(Service indicator)、业务指示符的长度、SUPI、SUPI的长度。在U2U中继业务中，SUPI为远端终端或中继终端的SUPI，当核心网网元与远端终端执行身份认证时，该SUPI为远端终端的SUPI，当核心网网元与中继终端执行身份认证时，该SUPI为中继终端的SUPI。业务指示为第一业务对应的业务指示符，例如，业务指示符为0x01表示ProSe业务(第一业务)；业务指示符为0x02表示测距业务(第一业务)。Method 1: The derivative function can be used to obtain the first key based on the third key. If a derivative function is used, the input of the derivative function includes at least one of the following: FC, the service indicator (Service indicator) of the first service, the length of the service indicator, SUPI, and the length of the SUPI. In the U2U relay service, SUPI is the SUPI of the remote terminal or relay terminal. When the core network element and the remote terminal perform identity authentication, the SUPI is the SUPI of the remote terminal. When the core network element and the relay When the terminal performs identity authentication, the SUPI is the SUPI of the relay terminal. The service indicator is a service indicator corresponding to the first service. For example, the service indicator is 0x01, which represents the ProSe service (the first service); the service indicator is 0x02, which represents the ranging service (the first service).

方式2：直接将第三密钥作为第一密钥。即，在进行第一业务的身份认证得到第三密钥后，将第三密钥确定为第一密钥，从而获取到第一密钥，使用第一密钥执行后续步骤。Method 2: Directly use the third key as the first key. That is, after the identity authentication of the first service is performed to obtain the third key, the third key is determined as the first key, thereby obtaining the first key, and the first key is used to perform subsequent steps.

在基于第三密钥衍生得到第一密钥标识的情况下，KDF的输入包括以下至少一项：第 一密钥标识字符串(Key ID string)、第一密钥标识字符串的长度、SUPI、SUPI的长度。第一密钥标识字符串与第一密钥的业务对应。例如，密钥标识字符串“PRUK-ID”表示ProSe业务(第一业务)，密钥标识字符串“RRUK-ID”表示测距业务(第一业务)。In the case where the first key identification is derived based on the third key, the input of the KDF includes at least one of the following: the first key identification string (Key ID string), the length of the first key identification string, SUPI , the length of SUPI. The first key identification string corresponds to the service of the first key. For example, the key identification string "PRUK-ID" represents the ProSe service (first service), and the key identification string "RRUK-ID" represents the ranging service (first service).

步骤301-13：远端终端基于第一密钥衍生得到第二子密钥(例如，K_{NR_U2U_ProSe})；核心网网元基于第一密钥衍生得到第二子密钥(例如，K_{NR_U2U_ProSe})；核心网网元向中继终端发送第二子密钥(例如，K_{NR_U2U_ProSe})。Step 301-13: The remote terminal derives the second subkey (for example, K_{NR_U2U_ProSe} ) based on the first key; the core network element derives the second subkey (for example, K_{NR_U2U_ProSe} ) based on the first key; The core network element sends the second subkey (for example, K_{NR_U2U_ProSe} ) to the relay terminal.

中继终端接收核心网网元发送的第二子密钥。The relay terminal receives the second subkey sent by the core network element.

第二子密钥为针对U2U中继业务的密钥。第二子密钥为使用单播链路进行通信的两个实体(中继终端和远端终端)间的中继业务根密钥。第二子密钥为中继终端与远端终端间通过单播链路进行通信的中继业务根密钥。第二子密钥为与特定U2U中继业务(第一ProSe U2U业务)绑定的中继业务根密钥。其长度可以为256位。第二子密钥用于在中继终端和远端终端间建立安全的单播链路。第二子密钥对应中继终端和远端终端。The second subkey is a key for the U2U relay service. The second subkey is the relay service root key between two entities (relay terminal and remote terminal) communicating using a unicast link. The second subkey is the relay service root key for communication between the relay terminal and the remote terminal through the unicast link. The second subkey is a relay service root key bound to a specific U2U relay service (first ProSe U2U service). Its length can be 256 bits. The second subkey is used to establish a secure unicast link between the relay terminal and the remote terminal. The second subkey corresponds to the relay terminal and the remote terminal.

第二子密钥与第一ProSe U2U业务绑定；在基于第一密钥衍生得到第二子密钥的情况下，KDF的输入包括以下至少一项：第一ProSe U2U业务的ProSe U2U业务代码、ProSe U2U业务代码的长度、随机数1、随机数1的长度、随机数2、随机数2的长度。The second subkey is bound to the first ProSe U2U service; when the second subkey is derived based on the first key, the input of the KDF includes at least one of the following: the ProSe U2U service code of the first ProSe U2U service , the length of ProSe U2U service code, random number 1, the length of random number 1, random number 2, and the length of random number 2.

步骤302：远端终端基于第二子密钥衍生得到第二会话密钥(例如，K_U2U-sess)；中继终端基于第二子密钥衍生得到第二会话密钥(例如，K_U2U-sess)。Step 302: The remote terminal derives the second session key (for example, K_U2U-sess ) based on the second subkey; the relay terminal derives the second session key (for example, K_U2U- sess) based on the second subkey._sess ).

步骤303：远端终端基于第二会话密钥(例如，K_U2U-sess)衍生得到第二加密密钥(例如，K_U2U-enc)和/或第二完整性密钥(例如，K_U2U-inc)；中继终端基于第二会话密钥(例如，K_U2U-sess)衍生得到第二加密密钥(例如，K_U2U-enc)和/或第二完整性密钥(例如，K_U2U-inc)。Step 303: The remote terminal derives the second encryption key (for example, K U2U-_{enc) and/or the second integrity key (for example, K U2U-sess} ) based on the second session key (for example, K_{U2U-sess) inc} ); the relay terminal derives the second encryption key (for example, K U2U_-enc) and/or the second integrity key (for example, K_U2U-inc ).

基于第二会话密钥衍生得到第二完整性密钥的方法可以参考TS33.503中所提供的方法。第二加密密钥等价于TS 33.536中的NRPEK；第二完整性密钥等价于TS 33.536中的NRPIK。For a method of deriving the second integrity key based on the second session key, refer to the method provided in TS33.503. The second encryption key is equivalent to NRPEK in TS 33.536; the second integrity key is equivalent to NRPIK in TS 33.536.

步骤304：远端终端与中继终端使用第二加密密钥和第二完整性密钥进行通信。Step 304: The remote terminal and the relay terminal communicate using the second encryption key and the second integrity key.

针对情况2：For case 2:

图12是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图12所示，该方法可以由远端终端、中继终端、核心网网元来执行。与图11所示的实施例不同的是，将步骤301-11至步骤301-13替换为：步骤301-21至步骤301-23：Figure 12 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 12, this method can be executed by remote terminals, relay terminals, and core network elements. What is different from the embodiment shown in Figure 11 is that steps 301-11 to 301-13 are replaced with: steps 301-21 to 301-23:

步骤301-21：中继终端与核心网网元进行第一业务的身份认证，得到第三密钥(例如，K_{AUSF_G})。Step 301-21: The relay terminal performs identity authentication on the first service with the core network element, and obtains the third key (for example, K_{AUSF_G} ).

其中，核心网网元可以是控制面网元，也可以是用户面网元。即，核心网网元可以是：AUSF、PAnF、PKMF、新的用户面网元或新的控制面网元。Among them, the core network element can be a control plane network element or a user plane network element. That is, the core network element can be: AUSF, PAnF, PKMF, a new user plane network element or a new control plane network element.

步骤301-22：中继终端基于第三密钥获取第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。核心网网元基于第三密钥获取第一密钥(例如，PRUK)和第一密钥标识(例如，PRUK ID)。Step 301-22: The relay terminal obtains the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key. The core network element obtains the first key (for example, PRUK) and the first key identification (for example, PRUK ID) based on the third key.

第三密钥获取第一密钥的方法参照上述实施例中的描述。The method for obtaining the first key by the third key refers to the description in the above embodiment.

步骤301-23：中继终端基于第一密钥衍生得到第二子密钥(例如，K_{NR_U2U_ProSe})；核心网网元基于第一密钥衍生得到第二子密钥(例如，K_{NR_U2U_ProSe})；核心网网元向远端终端发送第二子密钥(例如，K_{NR_U2U_ProSe})。Step 301-23: The relay terminal derives the second subkey (for example, K_{NR_U2U_ProSe} ) based on the first key; the core network element derives the second subkey (for example, K_{NR_U2U_ProSe} ) based on the first key; The core network element sends the second subkey (for example, K_{NR_U2U_ProSe} ) to the remote terminal.

远端终端接收核心网网元发送的第二子密钥。The remote terminal receives the second subkey sent by the core network element.

第二密钥衍生得到第二子密钥的方法参照上述实施例中的描述。For the method of deriving the second subkey from the second key, refer to the description in the above embodiment.

针对情况3：For case 3:

图13是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图13所示，该方法可以由远端终端、中继终端来执行。与图11所示的实施例不同的是，将步骤 301-11至步骤301-13替换为：步骤301-31至步骤301-33：Figure 13 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 13, this method can be executed by a remote terminal or a relay terminal. What is different from the embodiment shown in Figure 11 is that steps 301-11 to 301-13 are replaced with: steps 301-31 to 301-33:

步骤301-31：远端终端获取第一密钥和第一密钥标识；中继终端获取第一密钥和第一密钥标识。Step 301-31: The remote terminal obtains the first key and the first key identifier; the relay terminal obtains the first key and the first key identifier.

远端终端和中继终端基于预置信息获取第一密钥和第一密钥标识。例如，远端终端和中继终端读取预置信息提供的第一密钥和第一密钥标识，或，远端终端和中继终端根据预置信息生成第一密钥和第一密钥标识。The remote terminal and the relay terminal obtain the first key and the first key identifier based on the preset information. For example, the remote terminal and the relay terminal read the first key and the first key identifier provided by the preset information, or the remote terminal and the relay terminal generate the first key and the first key according to the preset information. logo.

步骤301-32：远端终端与中继终端协商生成第二子密钥的随机数。Step 301-32: The remote terminal negotiates with the relay terminal to generate a random number for the second subkey.

在基于第一密钥衍生得到第二子密钥的情况下，KDF的输入包括以下至少一项：第一ProSe U2U业务的ProSe U2U业务代码、ProSe U2U业务代码的长度、随机数1、随机数1的长度、随机数2、随机数2的长度。其中的随机数1和随机数2需要中继终端与远端终端协商确定。When the second subkey is derived based on the first key, the input of the KDF includes at least one of the following: the ProSe U2U service code of the first ProSe U2U service, the length of the ProSe U2U service code, the random number 1, the random number The length of 1, random number 2, and the length of random number 2. Random number 1 and random number 2 need to be determined through negotiation between the relay terminal and the remote terminal.

远端终端与中继终端协商衍生得到第二子秘钥所需要的随机数1和随机数2。The remote terminal negotiates with the relay terminal to derive the random number 1 and random number 2 required for the second sub-key.

步骤301-33：远端终端和中继终端各自基于协商结果从第一密钥衍生得到第二子密钥(K_{NR_U2U_ProSe})。Step 301-33: The remote terminal and the relay terminal each derive the second subkey (K_{NR_U2U_ProSe} ) from the first key based on the negotiation result.

远端终端和中继终端各自基于协商得到的随机数1、随机数2、第一密钥衍生得到第二子秘钥。The remote terminal and the relay terminal each derive the second sub-key based on the negotiated random number 1, random number 2, and the first key.

针对情况4：For case 4:

图14是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图14所示，该方法可以由远端终端、中继终端、核心网网元来执行。与图11所示的实施例不同的是，将步骤301-11至步骤301-13替换为：步骤301-41至步骤301-43：Figure 14 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 14, this method can be executed by remote terminals, relay terminals, and core network elements. What is different from the embodiment shown in Figure 11 is that steps 301-11 to 301-13 are replaced with: steps 301-41 to 301-43:

步骤301-41：远端终端根据预置信息获取第一密钥和第一密钥标识；中继终端接收核心网网元发送的第一密钥和第一密钥标识。Step 301-41: The remote terminal obtains the first key and the first key identifier according to the preset information; the relay terminal receives the first key and the first key identifier sent by the core network element.

若中继终端本地没有第一密钥和第一密钥标识，中继终端可以从核心网网元获取第一密钥和第一密钥标识。例如，中继终端在与核心网网元的注册、授权过程中，核心网网元生成第一密钥和第一密钥标识，并将第一密钥和第一密钥标识发送给中继终端。If the relay terminal does not have the first key and the first key identifier locally, the relay terminal can obtain the first key and the first key identifier from the core network element. For example, during the registration and authorization process between the relay terminal and the core network element, the core network element generates the first key and the first key identifier, and sends the first key and the first key identifier to the relay terminal.

远端终端根据预置信息获取第一密钥和第一密钥标识。例如，远端终端读取预置信息提供的第一密钥和第一密钥标识，或，远端终端基于预置信息生成第一密钥和第一密钥标识。The remote terminal obtains the first key and the first key identifier according to the preset information. For example, the remote terminal reads the first key and the first key identifier provided by the preset information, or the remote terminal generates the first key and the first key identifier based on the preset information.

步骤301-42：远端终端与中继终端协商生成第二子密钥的随机数。Step 301-42: The remote terminal negotiates with the relay terminal to generate a random number for the second subkey.

远端终端与中继终端协商衍生得到第二子秘钥所需要的随机数1和随机数2。The remote terminal negotiates with the relay terminal to derive the random number 1 and random number 2 required for the second sub-key.

步骤301-43：远端终端和中继终端各自基于协商结果从第一密钥衍生得到第二子密钥(K_{NR_U2U_ProSe})。Step 301-43: The remote terminal and the relay terminal each derive the second subkey (K_{NR_U2U_ProSe} ) from the first key based on the negotiation result.

远端终端和中继终端各自基于协商得到的随机数1、随机数2、第一密钥衍生得到第二子秘钥。The remote terminal and the relay terminal each derive the second sub-key based on the negotiated random number 1, random number 2, and the first key.

综上所述，本实施例提供的方法，提供了一种在U2U中继业务中的密钥层次结构，将用户面和控制面的密钥层次结构统一，将U2U与U2N的密钥层次结构整合，简化了ProSe的密钥层次结构，降低了密钥层次结构的复杂度，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided by this embodiment provides a key hierarchy in the U2U relay service, unifies the key hierarchies of the user plane and the control plane, and unifies the key hierarchies of U2U and U2N. Integration simplifies the ProSe key hierarchy, reduces the complexity of the key hierarchy, and reduces the burden on core network equipment and terminal equipment to execute ProSe security processes.

在一种可选的实施例中，给出一种在U2N中继业务中由控制面执行的邻近通信业务的密钥生成方法。In an optional embodiment, a key generation method for proximity communication services executed by the control plane in U2N relay services is provided.

图15是根据本申请实施例的一种邻近通信业务的密钥生成方法的流程图。如图15所示，该方法可以由远端终端、中继终端、远端AMF网元、中继AMF网元、远端AUSF网元来执行。该方法包括：Figure 15 is a flow chart of a key generation method for proximity communication services according to an embodiment of the present application. As shown in Figure 15, this method can be executed by a remote terminal, a relay terminal, a remote AMF network element, a relay AMF network element, and a remote AUSF network element. The method includes:

步骤501：远端终端注册到远端AMF，中继终端注册到中继AMF。Step 501: The remote terminal registers with the remote AMF, and the relay terminal registers with the relay AMF.

5G Prose远端终端和5G Pross中继终端到网络中注册，由网络进行认证和授权，以使用 /提供U2N中继业务。5G远端终端应通过网络认证和授权，以接收U2N中继业务。在该授权和信息提供过程中，将PC5安全策略分别提供给5G Prose远端终端和5G Prose中继终端。The 5G Prose remote terminal and the 5G Pross relay terminal register in the network, and are authenticated and authorized by the network to use/provide U2N relay services. 5G remote terminals should pass network authentication and authorization to receive U2N relay services. During the authorization and information provision process, the PC5 security policy is provided to the 5G Prose remote terminal and the 5G Prose relay terminal respectively.

步骤502：远端终端通过发现过程发现中继终端。Step 502: The remote terminal discovers the relay terminal through the discovery process.

远端终端应分别使用TS 23.304第6.3.1.2条或第6.3.1.3条中规定的任何A型或B型方法启动发现程序。The remote terminal shall initiate the discovery procedure using any Type A or Type B method specified in TS 23.304 clause 6.3.1.2 or 6.3.1.3 respectively.

步骤503：远端终端向中继终端发送直连通信请求。Step 503: The remote terminal sends a direct communication request to the relay terminal.

在发现5G Prose中继终端后，5G Prose远端终端应向5G Prose中继终端发送直连通信请求，以建立安全的PC5单播链路。按照TS 33.536的规定，5G远端终端应在DCR消息中包括其安全能力和PC5安全信令策略。该信息还应包括SUCI、中继业务代码、随机数Nonce_1。After discovering the 5G Prose relay terminal, the 5G Prose remote terminal should send a direct communication request to the 5G Prose relay terminal to establish a secure PC5 unicast link. According to the provisions of TS 33.536, the 5G remote terminal should include its security capabilities and PC5 security signaling policy in the DCR message. This information should also include SUCI, trunk service code, and random number Nonce_1.

步骤504：中继终端向中继AMF发送中继密钥请求。Step 504: The relay terminal sends a relay key request to the relay AMF.

在接收到DCR消息后，中继终端应向中继AMF发送中继密钥请求，包括在DCR消息中接收到的部分参数。After receiving the DCR message, the relay terminal shall send a relay key request to the relay AMF, including some of the parameters received in the DCR message.

步骤505：中继AMF向远端AUSF发送身份认证请求(Nausf_UEAuthentication_ProseAuthenticate)。Step 505: The relay AMF sends an identity authentication request (Nausf_UEAuthentication_ProseAuthenticate) to the remote AUSF.

5G Pross U2N中继终端还应在身份认证请求中携带事务标识符，该事务标识符用于在中继终端的NAS消息和PC5消息上为后续消息识别远程终端。中继AMF应验证中继终端是否被授权提供U2N中继业务。中继AMF应基于SUCI选择一个AUSF。并在Nausf_UEAuthentication_ProseAuthenticate请求消息中将中继密钥请求中接收到的参数转发给远端AUSF。Nausf_UEAuthentication_ProseAuthenticate请求消息应包含远端终端的SUCI、中继业务代码、Nonce_1。The 5G Pross U2N relay terminal should also carry a transaction identifier in the identity authentication request. The transaction identifier is used to identify the remote terminal for subsequent messages on the NAS message and PC5 message of the relay terminal. The relay AMF should verify whether the relay terminal is authorized to provide U2N relay services. The relay AMF shall select an AUSF based on SUCI. And forward the parameters received in the relay key request to the remote AUSF in the Nausf_UEAuthentication_ProseAuthenticate request message. The Nausf_UEAuthentication_ProseAuthenticate request message should contain the SUCI, relay service code, and Nonce_1 of the remote terminal.

步骤506：远端AUSF与远端终端进行特定业务的身份认证，得到第三密钥(KAUSF_G)。Step 506: The remote AUSF performs identity authentication for a specific service with the remote terminal, and obtains the third key (KAUSF_G).

远端AUSF应使用接收到的Prose特定参数(即RSC等)启动远端终端特定身份认证。5GProse远端AUSF应通过Nudm_UEAuthentication_GetProseAv请求消息从UDM检索认证向量，并触发5GProse远端终端的身份认证。该身份认证通过中继终端和中继AMF在远端AUSF和远端终端之间执行。UDM应根据SUPI选择认证方法。The remote AUSF shall initiate remote terminal specific identity authentication using the received Prose specific parameters (i.e. RSC, etc.). The 5GProse remote AUSF should retrieve the authentication vector from UDM through the Nudm_UEAuthentication_GetProseAv request message and trigger the identity authentication of the 5GProse remote terminal. This authentication is performed between the remote AUSF and the remote terminal through the relay terminal and the relay AMF. The UDM shall select the authentication method based on SUPI.

步骤507：远端终端基于第三密钥(K_{AUSF_G})衍生得到第一密钥(PRUK)和第一密钥标识(PRUK ID)。远端AUSF基于第三密钥衍生得到第一密钥和第一密钥标识。Step 507: The remote terminal derives the first key (PRUK) and the first key identification (PRUK ID) based on the third key (K_{AUSF_G} ). The remote AUSF derives the first key and the first key identifier based on the third key.

在成功认证后，远端终端和远端AUSF应使用新衍生的K_{AUSF_G}生成PRUK和PRUK ID。After successful authentication, the remote terminal and remote AUSF shall generate PRUK and PRUK ID using the newly derived K_{AUSF_G} .

步骤508：远端终端和远端AUSF各自基于第一密钥生成第一子密钥(K_{NR_U2N_ProSe})。Step 508: The remote terminal and the remote AUSF each generate a first subkey (K_{NR_U2N_ProSe} ) based on the first key.

步骤509：远端AUSF向中继AMF发送身份认证响应，身份认证响应中包括第一子密钥(K_{NR_U2N_ProSe})。Step 509: The remote AUSF sends an identity authentication response to the relay AMF, and the identity authentication response includes the first subkey (K_{NR_U2N_ProSe} ).

步骤510：中继AMF向中继终端发送中继密钥响应，中继密钥响应中包括第一子密钥(K_{NR_U2N_ProSe})。Step 510: The relay AMF sends a relay key response to the relay terminal, and the relay key response includes the first subkey (K_{NR_U2N_ProSe} ).

步骤511：远端终端和中继终端各自基于第一子密钥(K_{NR_U2N_ProSe})衍生得到第一会话密钥(K_relay-sess)，基于第一会话密钥衍生得到第一加密密钥(K_relay-enc)和第一完整性密钥(K_relay-inc)。远端终端和中继终端使用第一子密钥建立直通链路连接，使用第一加密密钥和第一完整性密钥通过直通链路进行会话通信。Step 511: The remote terminal and the relay terminal each derive the first session key (K_relay-sess ) based on the first sub-key (K_{NR_U2N_ProSe} ), and derive the first encryption key (K_relay-enc ) and the first integrity key (K_relay-inc ). The remote terminal and the relay terminal use the first subkey to establish a direct link connection, and use the first encryption key and the first integrity key to perform session communication through the direct link.

综上所述，本实施例提供的方法，通过使用特定业务身份认证得到的第三密钥(例如，K_{AUSF_G})，来衍生得到第一密钥(例如，5GPRUK)，简化了ProSe的密钥层次结构，使控制面和用户面的密钥层次结构相统一，降低了密钥层次结构的复杂度，降低了核心网设备和终端设备执行ProSe安全流程的负担。To sum up, the method provided in this embodiment uses the third key (for example, K_{AUSF_G} ) obtained by specific business identity authentication to derive the first key (for example, 5GPRUK), which simplifies the ProSe key. The hierarchical structure unifies the key hierarchies of the control plane and the user plane, reduces the complexity of the key hierarchical structure, and reduces the burden of core network equipment and terminal equipment in executing the ProSe security process.

图16示出了本申请一个示例性实施例提供的邻近通信业务的密钥生成装置的框图，所述装置包括：Figure 16 shows a block diagram of a key generation device for proximity communication services provided by an exemplary embodiment of the present application. The device includes:

第一生成模块601，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。The first generation module 601 is used to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, so The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到网络U2N中继业务的第一子密钥。In an optional design of this embodiment, the second key includes a first subkey for the terminal-to-network U2N relay service.

在本实施例的一个可选设计中，所述第一子密钥与第一U2N中继业务绑定；In an optional design of this embodiment, the first subkey is bound to the first U2N relay service;

在基于所述第一密钥衍生得到所述第一子密钥的情况下，密钥衍生函数KDF的输入包括以下至少一项：所述第一U2N中继业务的中继业务代码、所述中继业务代码的长度。When the first subkey is derived based on the first key, the input of the key derivation function KDF includes at least one of the following: the relay service code of the first U2N relay service, the The length of the trunk service code.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第一收发模块602，用于向中继终端发送所述第一子密钥，所述第一子密钥为所述中继终端与远端终端间通过所述PC5单播链路进行通信的中继业务根密钥。The first transceiver module 602 is configured to send the first subkey to the relay terminal, where the first subkey is used for communication between the relay terminal and the remote terminal through the PC5 unicast link. Relay service root key.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到终端U2U中继业务的第二子密钥。In an optional design of this embodiment, the second key includes a second subkey for the terminal-to-terminal U2U relay service.

在本实施例的一个可选设计中，所述第二子密钥与第一ProSe U2U业务绑定；In an optional design of this embodiment, the second subkey is bound to the first ProSe U2U service;

在基于所述第一密钥衍生得到所述第二子密钥的情况下，KDF的输入包括以下至少一项：所述第一ProSe U2U业务的ProSe U2U业务代码、所述ProSe U2U业务代码的长度。In the case where the second subkey is derived based on the first key, the input of the KDF includes at least one of the following: the ProSe U2U service code of the first ProSe U2U service, the ProSe U2U service code of the first ProSe U2U service code. length.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第一收发模块602，用于向远端终端和/或中继终端发送所述第二子密钥，所述第二子密钥为所述中继终端与远端终端间通过所述PC5单播链路进行通信的中继业务根密钥。The first transceiver module 602 is used to send the second sub-key to the remote terminal and/or the relay terminal. The second sub-key is a single link between the relay terminal and the remote terminal through the PC5. The trunk service root key for communication over the broadcast link.

在本实施例的一个可选设计中，所述第一密钥由第三密钥衍生得到；In an optional design of this embodiment, the first key is derived from the third key;

或，所述第一密钥为所述第三密钥；Or, the first key is the third key;

其中，所述第三密钥为通过第一业务的身份认证生成的中间密钥。Wherein, the third key is an intermediate key generated through identity authentication of the first service.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到所述第一密钥的情况下，KDF的输入包括以下至少一项：所述第一业务的业务指示符、所述业务指示符的长度。In an optional design of this embodiment, when the first key is derived based on the third key, the input of the KDF includes at least one of the following: a service indicator of the first service, The length of the service indicator.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到第一密钥标识的情况下，KDF的输入包括以下至少一项：所述第一密钥标识字符串、所述第一密钥标识字符串的长度。In an optional design of this embodiment, when the first key identification is derived based on the third key, the input of the KDF includes at least one of the following: the first key identification string, the The length of the first key identification string.

在本实施例的一个可选设计中，所述第一业务包括以下至少一项：邻近通信业务ProSe、测距业务。In an optional design of this embodiment, the first service includes at least one of the following: proximity communication service ProSe and ranging service.

在本实施例的一个可选设计中，所述核心网设备包括以下至少一项：鉴权服务器功能AUSF网元、邻近通信业务锚点功能PAnF网元、密钥管理功能PKMF网元、新的用户面网元、新的控制面网元。In an optional design of this embodiment, the core network equipment includes at least one of the following: authentication server function AUSF network element, proximity communication service anchor point function PAnF network element, key management function PKMF network element, new User plane network elements and new control plane network elements.

图17示出了本申请一个示例性实施例提供的邻近通信业务的密钥生成装置的框图，所述装置包括：Figure 17 shows a block diagram of a key generation device for proximity communication services provided by an exemplary embodiment of the present application. The device includes:

第二生成模块604，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The second generation module 604 is used to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, so The second key is a trunk service root key between two entities communicating using the PC5 unicast link.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到网络U2N中继业务的第一子密钥。In an optional design of this embodiment, the second key includes a first subkey for the terminal-to-network U2N relay service.

在本实施例的一个可选设计中，所述第一子密钥与第一U2N中继业务绑定；In an optional design of this embodiment, the first subkey is bound to the first U2N relay service;

在基于所述第一密钥衍生得到所述第一子密钥的情况下，密钥衍生函数KDF的输入包括以下至少一项：所述第一U2N中继业务的中继业务代码、所述中继业务代码的长度。When the first subkey is derived based on the first key, the input of the key derivation function KDF includes at least one of the following: the relay service code of the first U2N relay service, the The length of the trunk service code.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第二收发模块603，用于基于所述第一子密钥与中继终端建立针对所述U2N中继业务的所述PC5单播链路的安全。The second transceiver module 603 is configured to establish security of the PC5 unicast link for the U2N relay service with the relay terminal based on the first subkey.

在本实施例的一个可选设计中，所述第一子密钥用于衍生得到针对所述U2N中继业务的第一会话密钥，所述第一会话密钥用于保护所述远端终端与中继终端间针对所述U2N中继业务的通信会话。In an optional design of this embodiment, the first subkey is used to derive a first session key for the U2N relay service, and the first session key is used to protect the remote end. A communication session between the terminal and the relay terminal for the U2N relay service.

在本实施例的一个可选设计中，所述第一会话密钥用于衍生得到第一加密密钥和/或第一完整性密钥。In an optional design of this embodiment, the first session key is used to derive the first encryption key and/or the first integrity key.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到终端U2U中继业务的第二子密钥。In an optional design of this embodiment, the second key includes a second subkey for the terminal-to-terminal U2U relay service.

在本实施例的一个可选设计中，所述第二子密钥与第一ProSe U2U业务绑定；In an optional design of this embodiment, the second subkey is bound to the first ProSe U2U service;

在基于所述第一密钥衍生得到所述第二子密钥的情况下，KDF的输入包括以下至少一项：所述第一ProSe U2U业务的ProSe U2U业务代码、所述ProSe U2U业务代码的长度。In the case where the second subkey is derived based on the first key, the input of the KDF includes at least one of the following: the ProSe U2U service code of the first ProSe U2U service, the ProSe U2U service code of the first ProSe U2U service code. length.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第二收发模块603，用于基于所述第二子密钥与中继终端建立针对所述U2U中继业务的所述PC5单播链路的安全。The second transceiver module 603 is configured to establish security of the PC5 unicast link for the U2U relay service with the relay terminal based on the second subkey.

在本实施例的一个可选设计中，所述第二子密钥用于衍生得到针对所述U2U中继业务的第二会话密钥，所述第二会话密钥用于保护所述远端终端与中继终端间针对所述U2U业务的通信会话。In an optional design of this embodiment, the second subkey is used to derive a second session key for the U2U relay service, and the second session key is used to protect the remote end. A communication session between the terminal and the relay terminal for the U2U service.

在本实施例的一个可选设计中，所述第二会话密钥用于衍生得到第二加密密钥和/或第二完整性密钥。In an optional design of this embodiment, the second session key is used to derive a second encryption key and/or a second integrity key.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第二收发模块603，用于与所述中继终端协商所述第二子密钥；The second transceiver module 603 is used to negotiate the second subkey with the relay terminal;

或，所述第二生成模块604，用于生成所述第二子密钥；Or, the second generation module 604 is used to generate the second subkey;

或，第二收发模块603，用于接收核心网设备发送的所述第二子密钥。Or, the second transceiving module 603 is configured to receive the second subkey sent by the core network device.

在本实施例的一个可选设计中，所述第一密钥由第三密钥衍生得到；In an optional design of this embodiment, the first key is derived from the third key;

或，所述第一密钥为所述第三密钥；Or, the first key is the third key;

其中，所述第三密钥为通过第一业务的身份认证生成的中间密钥。Wherein, the third key is an intermediate key generated through identity authentication of the first service.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到所述第一密钥的情况下，KDF的输入包括以下至少一项：所述第一业务的业务指示符、所述业务指示符的长度。In an optional design of this embodiment, when the first key is derived based on the third key, the input of the KDF includes at least one of the following: a service indicator of the first service, The length of the service indicator.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到第一密钥标识的情况下，KDF的输入包括以下至少一项：所述第一密钥标识字符串、所述第一密钥标识字符串的长度。In an optional design of this embodiment, when the first key identification is derived based on the third key, the input of the KDF includes at least one of the following: the first key identification string, the The length of the first key identification string.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

第二收发模块603，用于与核心网设备执行所述第一业务的身份认证生成所述第三密钥；The second transceiver module 603 is configured to perform identity authentication of the first service with core network equipment to generate the third key;

其中，所述核心网设备包括以下至少一项：鉴权服务器功能AUSF网元、邻近通信业务锚点功能PAnF网元、密钥管理功能PKMF网元、新的用户面网元、新的控制面网元。Wherein, the core network equipment includes at least one of the following: authentication server function AUSF network element, proximity communication service anchor point function PAnF network element, key management function PKMF network element, new user plane network element, new control plane network element.

在本实施例的一个可选设计中，所述第一业务包括以下至少一项：邻近通信业务ProSe、测距业务。In an optional design of this embodiment, the first service includes at least one of the following: proximity communication service ProSe and ranging service.

图18示出了本申请一个示例性实施例提供的一种邻近通信业务的密钥生成装置的框图，所述装置包括：Figure 18 shows a block diagram of a key generation device for proximity communication services provided by an exemplary embodiment of the present application. The device includes:

第三收发模块605，用于获取第二密钥，所述第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，所述第一密钥为使用邻近通信业务的实体的PC5根 密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The third transceiver module 605 is used to obtain a second key, which is a user plane and/or control plane key derived in the same derivation method based on the first key. is the PC5 root key of the entity using the proximity communication service, and the second key is the relay service root key between the two entities using the PC5 unicast link to communicate.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到网络U2N中继业务的第一子密钥。In an optional design of this embodiment, the second key includes a first subkey for the terminal-to-network U2N relay service.

在本实施例的一个可选设计中，所述第一子密钥与第一U2N中继业务绑定；In an optional design of this embodiment, the first subkey is bound to the first U2N relay service;

在基于所述第一密钥衍生得到所述第一子密钥的情况下，密钥衍生函数KDF的输入包括以下至少一项：所述第一U2N中继业务的中继业务代码、所述中继业务代码的长度。When the first subkey is derived based on the first key, the input of the key derivation function KDF includes at least one of the following: the relay service code of the first U2N relay service, the The length of the trunk service code.

在本实施例的一个可选设计中，所述第三收发模块605，用于基于所述第一子密钥与远端终端建立针对所述U2N中继业务的所述PC5单播链路的安全。In an optional design of this embodiment, the third transceiver module 605 is configured to establish the PC5 unicast link for the U2N relay service with the remote terminal based on the first subkey. Safety.

在本实施例的一个可选设计中，所述第一子密钥用于衍生得到针对所述U2N中继业务的第一会话密钥，所述第一会话密钥用于保护远端终端与所述中继终端间针对所述U2N中继业务的通信会话。In an optional design of this embodiment, the first subkey is used to derive a first session key for the U2N relay service, and the first session key is used to protect the remote terminal and A communication session between the relay terminals for the U2N relay service.

在本实施例的一个可选设计中，所述第一会话密钥用于衍生得到第一加密密钥和/或第一完整性密钥。In an optional design of this embodiment, the first session key is used to derive the first encryption key and/or the first integrity key.

在本实施例的一个可选设计中，所述第三收发模块605，用于接收核心网设备发送的所述第一子密钥。In an optional design of this embodiment, the third transceiver module 605 is configured to receive the first subkey sent by the core network device.

在本实施例的一个可选设计中，所述第二密钥包括针对终端到终端U2U中继业务的第二子密钥。In an optional design of this embodiment, the second key includes a second subkey for the terminal-to-terminal U2U relay service.

在本实施例的一个可选设计中，所述第二子密钥与第一ProSe U2U业务绑定；In an optional design of this embodiment, the second subkey is bound to the first ProSe U2U service;

在基于所述第一密钥衍生得到所述第二子密钥的情况下，KDF的输入包括以下至少一项：所述第一ProSe U2U业务的ProSe U2U业务代码、所述ProSe U2U业务代码的长度。In the case where the second subkey is derived based on the first key, the input of the KDF includes at least one of the following: the ProSe U2U service code of the first ProSe U2U service, the ProSe U2U service code of the first ProSe U2U service code. length.

在本实施例的一个可选设计中，所述第三收发模块605，用于基于所述第二子密钥与远端终端建立针对所述U2U中继业务的所述PC5单播链路的安全。In an optional design of this embodiment, the third transceiver module 605 is configured to establish the PC5 unicast link for the U2U relay service with the remote terminal based on the second subkey. Safety.

在本实施例的一个可选设计中，所述第二子密钥用于衍生得到针对所述U2U中继业务的第二会话密钥，所述第二会话密钥用于保护远端终端与所述中继终端间针对所述U2U业务的通信会话。In an optional design of this embodiment, the second subkey is used to derive a second session key for the U2U relay service, and the second session key is used to protect the remote terminal and A communication session between the relay terminals for the U2U service.

在本实施例的一个可选设计中，所述第二会话密钥用于衍生得到第二加密密钥和/或第二完整性密钥。In an optional design of this embodiment, the second session key is used to derive a second encryption key and/or a second integrity key.

在本实施例的一个可选设计中，所述装置还包括：In an optional design of this embodiment, the device further includes:

所述第三收发模块605，用于与远端终端协商生成所述第二子密钥；The third transceiver module 605 is used to negotiate with the remote terminal to generate the second subkey;

或，第三生成模块606，用于生成所述第二子密钥；Or, a third generation module 606, used to generate the second subkey;

或，所述第三收发模块605，用于接收核心网设备发送的所述第二子密钥。Or, the third transceiving module 605 is configured to receive the second subkey sent by the core network device.

在本实施例的一个可选设计中，所述第一密钥由第三密钥衍生得到；In an optional design of this embodiment, the first key is derived from the third key;

或，所述第一密钥为所述第三密钥；Or, the first key is the third key;

其中，所述第三密钥为通过第一业务的身份认证生成的中间密钥。Wherein, the third key is an intermediate key generated through identity authentication of the first service.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到所述第一密钥的情况下，KDF的输入包括以下至少一项：所述第一业务的业务指示符、所述业务指示符的长度。In an optional design of this embodiment, when the first key is derived based on the third key, the input of the KDF includes at least one of the following: a service indicator of the first service, The length of the service indicator.

在本实施例的一个可选设计中，在基于所述第三密钥衍生得到第一密钥标识的情况下，KDF的输入包括以下至少一项：所述第一密钥标识字符串、所述第一密钥标识字符串的长度。In an optional design of this embodiment, when the first key identification is derived based on the third key, the input of the KDF includes at least one of the following: the first key identification string, the The length of the first key identification string.

在本实施例的一个可选设计中，所述第一业务包括以下至少一项：邻近通信业务ProSe、测距业务。In an optional design of this embodiment, the first service includes at least one of the following: proximity communication service ProSe and ranging service.

在本实施例的一个可选设计中，所述核心网设备包括以下至少一项：鉴权服务器功能AUSF网元、邻近通信业务锚点功能PAnF网元、密钥管理功能PKMF网元、新的用户面网元、新的控制面网元。In an optional design of this embodiment, the core network equipment includes at least one of the following: authentication server function AUSF network element, proximity communication service anchor point function PAnF network element, key management function PKMF network element, new User plane network elements and new control plane network elements.

需要说明的一点是，上述实施例提供的装置在实现其功能时，仅以上述各个功能模块的划分进行举例说明，实际应用中，可以根据实际需要而将上述功能分配由不同的功能模块完成，即将设备的内容结构划分成不同的功能模块，以完成以上描述的全部或者部分功能。It should be noted that when the device provided in the above embodiment implements its functions, only the division of the above functional modules is used as an example. In practical applications, the above functions can be allocated to different functional modules according to actual needs. That is, the content structure of the device is divided into different functional modules to complete all or part of the functions described above.

关于上述实施例中的装置，其中各个模块执行操作的具体方式已经在有关该方法的实施例中进行了详细描述，此处将不做详细阐述说明。Regarding the devices in the above embodiments, the specific manner in which each module performs operations has been described in detail in the embodiments related to the method, and will not be described in detail here.

图19示出了本申请一个实施例提供的通信设备(终端设备或网络设备)的结构示意图。该通信设备可以包括：处理器1801、接收器1802、发送器1803、存储器1804和总线1805。Figure 19 shows a schematic structural diagram of a communication device (terminal device or network device) provided by an embodiment of the present application. The communication device may include: a processor 1801, a receiver 1802, a transmitter 1803, a memory 1804, and a bus 1805.

处理器1801包括一个或者一个以上处理核心，处理器1801通过运行软件程序以及模块，从而执行各种功能应用以及进行数据发送。The processor 1801 includes one or more processing cores. The processor 1801 executes various functional applications and transmits data by running software programs and modules.

接收器1802和发送器1803可以实现为一个收发器1806，该收发器1806可以是一块通信芯片。The receiver 1802 and the transmitter 1803 can be implemented as a transceiver 1806, and the transceiver 1806 can be a communication chip.

存储器1804通过总线1805与处理器1801相连。Memory 1804 is connected to processor 1801 through bus 1805.

存储器1804可用于存储计算机程序，处理器1801用于执行该计算机程序，以实现上述方法实施例中核心网设备侧或远端终端设备侧或中继终端侧中至少一个设备侧的方法。The memory 1804 can be used to store a computer program, and the processor 1801 is used to execute the computer program to implement the method on at least one of the core network device side, the remote terminal device side, or the relay terminal side in the above method embodiments.

此外，存储器1804可以由任何类型的易失性或非易失性存储设备或者它们的组合实现，易失性或非易失性存储设备包括但不限于：随机存储器(Random-Access Memory，RAM)和只读存储器(Read-Only Memory，ROM)、可擦写可编程只读存储器(Erasable Programmable Read-Only Memory，EPROM)、电可擦写可编程只读存储器(Electrically Erasable Programmable Read-Only Memory，EEPROM)、闪存或其他固态存储其技术，只读光盘(Compact Disc Read-Only Memory，CD-ROM)、高密度数字视频光盘(Digital Video Disc，DVD)或其他光学存储、磁带盒、磁带、磁盘存储或其他磁性存储设备。In addition, the memory 1804 may be implemented by any type of volatile or non-volatile storage device, or a combination thereof, including but not limited to: Random-Access Memory (RAM) And read-only memory (Read-Only Memory, ROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), flash memory or other solid-state storage technology, compact disc (Compact Disc Read-Only Memory, CD-ROM), high-density digital video disc (Digital Video Disc, DVD) or other optical storage, tape cassette, magnetic tape, magnetic disk storage or other magnetic storage device.

其中，当通信设备实现为核心网设备时，本申请实施例涉及的处理器和收发器，可以执行上述图6至图15任一所示的方法中，由核心网设备执行的步骤，此处不再赘述。When the communication device is implemented as a core network device, the processor and transceiver involved in the embodiment of the present application can perform the steps performed by the core network device in any of the methods shown in Figure 6 to Figure 15. Here, No longer.

在一种可能的实现方式中，当通信设备实现为核心网设备时，In a possible implementation, when the communication device is implemented as a core network device,

所述处理器，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用PC5单播链路进行通信的两个实体间的中继业务根密钥。The processor is configured to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

其中，当通信设备实现为远端终端时，本申请实施例涉及的处理器和收发器，可以执行上述图6至图15任一所示的方法中，由远端终端执行的步骤，此处不再赘述。When the communication device is implemented as a remote terminal, the processor and transceiver involved in the embodiment of the present application can perform the steps performed by the remote terminal in any of the methods shown in Figure 6 to Figure 15. Here, No longer.

所述处理器，用于基于第一密钥以相同衍生方式衍生得到用户面和控制面的第二密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The processor is configured to derive the second key of the user plane and the control plane in the same derivation method based on the first key, where the first key is the PC5 root key of the entity using the proximity communication service, and the The second key is the trunk service root key between two entities communicating using the PC5 unicast link.

其中，当通信设备实现为中继终端时，本申请实施例涉及的处理器和收发器，可以执行上述图6至图15任一所示的方法中，由中继终端执行的步骤，此处不再赘述。When the communication device is implemented as a relay terminal, the processor and transceiver involved in the embodiment of the present application can perform the steps performed by the relay terminal in any of the methods shown in Figure 6 to Figure 15, where No longer.

所述收发器，用于获取第二密钥，所述第二密钥是基于第一密钥以相同衍生方式衍生得到的用户面和/或控制面的密钥，所述第一密钥为使用邻近通信业务的实体的PC5根密钥，所述第二密钥为使用所述PC5单播链路进行通信的两个实体间的中继业务根密钥。The transceiver is used to obtain a second key. The second key is a user plane and/or control plane key derived in the same derivation method based on the first key. The first key is Using the PC5 root key of the entity adjacent to the communication service, the second key is the relay service root key between the two entities communicating using the PC5 unicast link.

本申请实施例还提供了一种计算机可读存储介质，所述存储介质中存储有计算机程序，所述计算机程序用于被计算机设备的处理器执行，以实现上述方法实施例中核心网设备侧或远端终端设备侧或中继终端侧中至少一个设备侧的方法。Embodiments of the present application also provide a computer-readable storage medium. A computer program is stored in the storage medium. The computer program is used to be executed by a processor of a computer device to implement the core network device side in the above method embodiment. Or a method on at least one of the remote terminal equipment side or the relay terminal side.

可选地，该计算机可读存储介质可以包括：只读存储器(Read-Only Memory，ROM)、随机存储器(Random-Access Memory，RAM)、固态硬盘(Solid State Drives，SSD)或光盘等。其中，随机存取记忆体可以包括电阻式随机存取记忆体(Resistance Random Access Memory，ReRAM)和动态随机存取存储器(Dynamic Random Access Memory，DRAM)。Optionally, the computer-readable storage medium may include: read-only memory (Read-Only Memory, ROM), random access memory (Random-Access Memory, RAM), solid state drives (Solid State Drives, SSD) or optical disks, etc. Among them, random access memory may include resistive random access memory (Resistance Random Access Memory, ReRAM) and dynamic random access memory (Dynamic Random Access Memory, DRAM).

本申请实施例还提供了一种芯片，所述芯片包括可编程逻辑电路和/或程序指令，当所述芯片在终端设备上运行时，用于实现上述方法实施例中核心网设备侧或远端终端设备侧或中继终端侧中至少一个设备侧的方法。Embodiments of the present application also provide a chip. The chip includes programmable logic circuits and/or program instructions. When the chip is run on a terminal device, it is used to implement the core network device side or remote operation in the above method embodiments. A method on at least one device side of the end terminal device side or the relay terminal side.

本申请实施例还提供了一种计算机程序产品或计算机程序，所述计算机程序产品或计算机程序包括计算机指令，所述计算机指令存储在计算机可读存储介质中，终端设备的处理器从所述计算机可读存储介质读取并执行所述计算机指令，以实现上述方法实施例中核心网设备侧或远端终端设备侧或中继终端侧中至少一个设备侧的方法。Embodiments of the present application also provide a computer program product or computer program. The computer program product or computer program includes computer instructions. The computer instructions are stored in a computer-readable storage medium. The processor of the terminal device obtains the information from the computer. The readable storage medium reads and executes the computer instructions to implement the method on at least one of the core network equipment side, the remote terminal equipment side, or the relay terminal side in the above method embodiment.

通过以上的实施方式的描述，本领域的技术人员可以清楚地了解到根据上述实施例的方法可借助软件加必需的通用硬件平台的方式来实现，当然也可以通过硬件，但很多情况下前者是更佳的实施方式。基于这样的理解，本申请的技术方案本质上或者说对现有技术做出贡献的部分可以以软件产品的形式体现出来，该计算机软件产品存储在一个存储介质(如ROM/RAM、磁碟、光盘)中，包括若干指令用以使得一台终端设备(可以是手机，计算机，业务器，或者网络设备等)执行本申请各个实施例所述的方法。Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by means of software plus the necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is Better implementation. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence or that contributes to the existing technology. The computer software product is stored in a storage medium (such as ROM/RAM, disk, CD), includes several instructions to cause a terminal device (which can be a mobile phone, a computer, a business server, or a network device, etc.) to execute the methods described in various embodiments of this application.

显然，本领域的技术人员应该明白，上述的本申请的各模块或各步骤可以用通用的计算装置来实现，它们可以集中在单个的计算装置上，或者分布在多个计算装置所组成的网络上，可选地，它们可以用计算装置可执行的程序代码来实现，从而，可以将它们存储在存储装置中由计算装置来执行，并且在某些情况下，可以以不同于此处的顺序执行所示出或描述的步骤，或者将它们分别制作成各个集成电路模块，或者将它们中的多个模块或步骤制作成单个集成电路模块来实现。这样，本申请不限制于任何特定的硬件和软件结合。Obviously, those skilled in the art should understand that the above-mentioned modules or steps of the present application can be implemented using general-purpose computing devices, and they can be concentrated on a single computing device, or distributed across a network composed of multiple computing devices. , optionally, they may be implemented in program code executable by a computing device, such that they may be stored in a storage device for execution by the computing device, and in some cases, may be in a sequence different from that herein. The steps shown or described are performed either individually as individual integrated circuit modules, or as multiple modules or steps among them as a single integrated circuit module. As such, the application is not limited to any specific combination of hardware and software.

以上所述仅为本申请的可选实施例而已，并不用于限制本申请，对于本领域的技术人员来说，本申请可以有各种更改和变化。凡在本申请的原则之内，所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。The above are only optional embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles of this application shall be included in the protection scope of this application.

Claims (56)

1. A method of key generation for proximity communication services, the method being performed by a core network device, the method comprising:

   And deriving a second key of the user plane and the control plane in the same derivation mode based on a first key, wherein the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using a PC5 unicast link for communication.
2. The method of claim 1, wherein the second key comprises a first subkey for terminal-to-network U2N relay traffic.
3. The method of claim 2, wherein the first subkey is bound to a first U2N relay service;

   in case the first sub-key is derived based on the first key, the input of the key derivation function KDF comprises at least one of: and the relay service code of the first U2N relay service and the length of the relay service code.
4. A method according to claim 2 or 3, characterized in that the method further comprises:

   and sending the first sub-key to a relay terminal, wherein the first sub-key is a relay service root key for communication between the relay terminal and a remote terminal through the PC5 unicast link.
5. The method according to any of claims 1 to 4, characterized in that the second key comprises a second sub-key for terminal-to-terminal U2U relay traffic.
6. The method of claim 5, wherein the second subkey is service bound with the first ProSe U2U;

   in the case of deriving the second subkey based on the first key, the input of the KDF comprises at least one of: and the ProSe U2U service code of the first ProSe U2U service and the length of the ProSe U2U service code.
7. The method according to claim 5 or 6, characterized in that the method further comprises:

   and sending the second sub-key to a relay terminal and/or a remote terminal, wherein the second sub-key is a relay service root key for communication between the relay terminal and the remote terminal through the PC5 unicast link.
8. The method according to any one of claims 1 to 7, wherein,

   in case the core network device comprises a user plane network element or a control plane network element, the first key is derived from a third key;

   or, in the case that the core network device includes a user plane network element, the first key is the third key;

   the third key is an intermediate key generated through identity authentication of the first service.
9. The method of claim 8, wherein the input of the KDF if the first key is derived based on the third key comprises at least one of: a service indicator of the first service, and a length of the service indicator.
10. The method according to claim 8 or 9, wherein the input of the KDF in case the first key identity is derived based on the third key comprises at least one of: the first key identification string, the length of the first key identification string.
11. The method according to any of claims 8 to 10, wherein the first traffic comprises at least one of: proximity communication service ProSe, ranging service.
12. The method according to any of claims 1 to 11, wherein the core network device comprises at least one of: an authentication server function AUSF network element, a neighboring communication service anchor function PAnF network element, a key management function PKMF network element, a new user plane network element and a new control plane network element.
13. A method of key generation for proximity communication services, the method being performed by a remote terminal, the method comprising:

    deriving a second key of the user plane and the control plane in the same derivation mode based on a first key, wherein the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using the PC5 unicast link for communication.
14. The method of claim 13, wherein the second key comprises a first subkey for terminal-to-network U2N relay traffic.
15. The method of claim 14, wherein the first subkey is bound to a first U2N relay service;

    in case the first sub-key is derived based on the first key, the input of the key derivation function KDF comprises at least one of: and the relay service code of the first U2N relay service and the length of the relay service code.
16. The method according to claim 14 or 15, characterized in that the method further comprises:

    and establishing the security of the PC5 unicast link aiming at the U2N relay service based on the first subkey and a relay terminal.
17. The method according to any of the claims 14 to 15, wherein the first sub-key is used for deriving a first session key for the U2N relay service, the first session key being used for protecting a communication session for the U2N relay service between the remote terminal and a relay terminal.
18. The method according to claim 17, wherein the first session key is used to derive a first encryption key and/or a first integrity key.
19. The method according to any of the claims 13 to 18, characterized in that the second key comprises a second sub-key for terminal-to-terminal U2U relay traffic.
20. The method of claim 19, wherein the second subkey is service bound with the first ProSe U2U;

    in the case of deriving the second subkey based on the first key, the input of the KDF comprises at least one of: and the ProSe U2U service code of the first ProSe U2U service and the length of the ProSe U2U service code.
21. The method according to claim 19 or 20, characterized in that the method further comprises:

    and establishing the security of the PC5 unicast link aiming at the U2U relay service based on the second subkey and a relay terminal.
22. The method according to any of the claims 19 to 21, wherein the second sub-key is used for deriving a second session key for the U2U relay service, the second session key being used for protecting a communication session for the U2U service between the remote terminal and the relay terminal.
23. The method according to claim 22, wherein the second session key is used to derive a second encryption key and/or a second integrity key.
24. The method according to any one of claims 19 to 23, further comprising:

    negotiating the second subkey with the relay terminal;

    or, generating the second subkey;

    or, receiving the second subkey sent by the core network device.
25. The method of any one of claims 13 to 24, wherein the first key is derived from a third key;

    or, the first key is the third key;

    the third key is an intermediate key generated through identity authentication of the first service.
26. The method of claim 25, wherein the input of a KDF if the first key is derived based on the third key comprises at least one of: a service indicator of the first service, and a length of the service indicator.
27. The method according to claim 25 or 26, wherein the input of the KDF in case the first key identity is derived based on the third key comprises at least one of: the first key identification string, the length of the first key identification string.
28. The method according to any one of claims 25 to 27, further comprising:

    The identity authentication of the first service is executed with core network equipment to generate the third secret key;

    wherein the core network device comprises at least one of: an authentication server function AUSF network element, a neighboring communication service anchor function PAnF network element, a key management function PKMF network element, a new user plane network element and a new control plane network element.
29. The method according to any of claims 25 to 28, wherein the first service comprises at least one of: proximity communication service ProSe, ranging service.
30. A key generation method of proximity communication service, the method being performed by a relay terminal, the method comprising:

    and acquiring a second key, wherein the second key is a key of a user plane and/or a control plane which is derived in the same derivation mode based on a first key, the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using the PC5 unicast link for communication.
31. The method of claim 30, wherein the second key comprises a first subkey for terminal-to-network U2N relay traffic.
32. The method of claim 31, wherein the first subkey is bound to a first U2N relay service;

    in case the first sub-key is derived based on the first key, the input of the key derivation function KDF comprises at least one of: and the relay service code of the first U2N relay service and the length of the relay service code.
33. The method according to claim 31 or 32, characterized in that the method further comprises:

    and establishing the security of the PC5 unicast link aiming at the U2N relay service with a remote terminal based on the first subkey.
34. The method according to any of the claims 31 to 32, wherein the first sub-key is used for deriving a first session key for the U2N relay service, the first session key being used for protecting a communication session for the U2N relay service between a remote terminal and the relay terminal.
35. The method according to claim 34, wherein the first session key is used to derive a first encryption key and/or a first integrity key.
36. The method according to any one of claims 31 to 35, wherein the obtaining the second key comprises:

    And receiving the first subkey sent by the core network equipment.
37. The method according to any of claims 30 to 36, wherein the second key comprises a second sub-key for terminal-to-terminal U2U relay traffic.
38. The method of claim 37, wherein the second subkey is service bound with the first ProSe U2U;

    in the case of deriving the second subkey based on the first key, the input of the KDF comprises at least one of: and the ProSe U2U service code of the first ProSe U2U service and the length of the ProSe U2U service code.
39. The method according to claim 37 or 38, characterized in that the method further comprises:

    and establishing the security of the PC5 unicast link aiming at the U2U relay service with a remote terminal based on the second subkey.
40. A method according to any of claims 37 to 39, wherein the second sub-key is used to derive a second session key for the U2U relay service, the second session key being used to secure a communication session for the U2U service between a remote terminal and the relay terminal.
41. A method as defined in claim 40, wherein the second session key is used to derive a second encryption key and/or a second integrity key.
42. The method of any one of claims 37 to 41, wherein the obtaining the second key comprises:

    negotiating with a remote terminal to generate the second subkey;

    or, generating the second subkey;

    or, receiving the second subkey sent by the core network device.
43. The method of any one of claims 30 to 42, wherein the first key is derived from a third key;

    or, the first key is the third key;

    the third key is an intermediate key generated through identity authentication of the first service.
44. The method of claim 43, wherein, in the case of deriving the first key based on the third key, the input of the KDF comprises at least one of: a service indicator of the first service, and a length of the service indicator.
45. The method of claim 43 or 44, wherein the input of the KDF comprises at least one of: the first key identification string, the length of the first key identification string.
46. The method of any one of claims 43 to 45, wherein the first service comprises at least one of: proximity communication service ProSe, ranging service.
47. The method of claim 46, wherein the core network device comprises at least one of: an authentication server function AUSF network element, a neighboring communication service anchor function PAnF network element, a key management function PKMF network element, a new user plane network element and a new control plane network element.
48. A key generation apparatus for proximity communication traffic, the apparatus comprising:

    the first generation module is used for deriving a second key of the user plane and the control plane in the same derivation mode based on a first key, wherein the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using a PC5 unicast link for communication.
49. A key generation apparatus for proximity communication traffic, the apparatus comprising:

    and the second generation module is used for deriving a second key of the user plane and the control plane in the same derivation mode based on the first key, wherein the first key is a PC5 root key of an entity using the adjacent communication service, and the second key is a relay service root key between two entities using the PC5 unicast link for communication.
50. A key generation apparatus for proximity communication traffic, the apparatus comprising:

    And the third transceiver module is used for acquiring a second key, wherein the second key is a key of a user plane and/or a control plane which is derived in the same derivation mode based on the first key, the first key is a PC5 root key of an entity using the adjacent communication service, and the second key is a relay service root key between two entities using the PC5 unicast link for communication.
51. A core network device, characterized in that the core network device comprises a processor;

    the processor is configured to derive a second key of the user plane and the control plane in the same derivation manner based on a first key, where the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using a PC5 unicast link for communication.
52. A terminal device, characterized in that the terminal device comprises a processor;

    the processor is configured to derive a second key of the user plane and the control plane in the same derivation manner based on a first key, where the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using the PC5 unicast link for communication.
53. A terminal device, characterized in that the terminal device comprises a transceiver;

    the transceiver is configured to obtain a second key, where the second key is a key of a user plane and/or a control plane derived based on a first key in the same derivation manner, the first key is a PC5 root key of an entity using proximity communication service, and the second key is a relay service root key between two entities using the PC5 unicast link to perform communication.
54. A computer readable storage medium, characterized in that the storage medium has stored therein a computer program for execution by a processor for implementing the method of any one of claims 1 to 47.
55. A chip comprising programmable logic circuitry and/or program instructions for implementing the method of any one of claims 1 to 47 when the chip is run.
56. A computer program product or computer program comprising computer instructions stored in a computer readable storage medium from which a processor reads and executes the computer instructions to implement the method of any one of claims 1 to 47.