WO2007022731A1

WO2007022731A1 - Encryption key negotiation method, system and equipment in the enhanced universal verify frame

Info

Publication number: WO2007022731A1
Application number: PCT/CN2006/002181
Authority: WO
Inventors: Yanmei Yang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2005-08-26
Filing date: 2006-08-25
Publication date: 2007-03-01
Also published as: CN1921682A; CN1921682B

Abstract

A method of Encryption key negotiation in the enhanced universal verify frame is applied in the communication derived key negotiation between the NAF and the subscriber thereof, which includes: the peripheral terminal device requests the derived key from UE, the request carries on the peripheral terminal device tag; UE computes the first derived key according to the shared key with BSF and the peripheral terminal device tag; the network side computes the second derived key according to the shared key which shared by UE and BSF and the peripheral terminal device tag obtained, and the second derived key is memorized by NAF. The encryption key negotiation system and equipment are also provided in the present invention. It can realize which the GBA subscriber side is in the UE, while NAF subscriber is in the other peripheral terminal device, NAF subscriber and NAF negotiate the key.

Description

Key agreement method, system and device in enhanced universal authentication framework

Technical field

The present invention relates to the technical field of the 3GPP Generic Authentication Architecture (GAA), and in particular to a key agreement method, system and apparatus in an enhanced universal authentication framework. Background of the invention

In the third generation wireless communication standard, GAA is a general structure used by various application service entities to complete the verification of user identity. GAA can be used to check and verify the identity of users of application services. The foregoing multiple application services may be multicast or broadcast services, user certificate services, information provision services, or proxy services.

Figure 1 shows the structure of the GAA. The GAA is usually composed of a UE, a BSF (Bootstrapping Server Function), a Home Subscriber System (HSS), and a Network Application Function (NAF). The BSF and the UE mutually authenticate the identity, and simultaneously generate the shared key Ks of the BSF and the UE; the HSS stores a profile file for describing the user information, and the HSS also has the function of generating the authentication information. The interface between the various entities can be seen in Figure 1.

When the user needs to use a service, if the UE needs to go to the BSF to perform the mutual authentication process, the UE directly authenticates to the BSF. Otherwise, the UE first contacts the NAF corresponding to the service, if the NAF is used. The GAA, and finds that the UE has not yet reached the BSF for mutual authentication, and the NAF notifies the UE to the BSF for mutual authentication to verify the identity.

The mutual authentication between the UE and the BSF is the Bootstrapping rights under the General Bootstrapping Authentication Framework (GBA, Generic Bootstrapping Architecture). The method includes: the UE sends an authentication request to the BSF; after receiving the authentication request, the BSF first obtains the authentication information of the user from the HSS; after obtaining the authentication information, the BSF uses the HTTP digest AKA protocol to perform mutual authentication and key agreement with the UE, and completes The mutual authentication of the identity between the UE and the BSF and the generation of the shared key Ks, the BSF also defines an expiration date for the shared key Ks, so that the Ks performs regular updates. The shared key Ks is used as a root key to derive a key for encrypted communication.

Then, the BSF allocates a Bootstrapping Transaction Identifier (B-TID) to the UE, and the B-TID is associated with Ks, which can be used to identify the Ks, and also includes the expiration date of the Ks.

After receiving the B-TID, the UE sends a connection request to the NAF again, and the B-TID is carried in the request message, and the UE side calculates the derived key NAF specific keys according to Ks (may be Ks-NAF, or Ks- Int—NAF and Ks—ext—NAF, as explained later).

After receiving the connection request, the NAF first queries the B-TID of the user. If the NAF cannot query the B-TID locally, the NAF queries the BSF. The query carries the NAF identifier and the B-TID. . If the BSF cannot query the B-TID locally, the NAF is notified that there is no information about the user. At this time, the NAF will notify the UE to re-authenticate the authentication to the BSF. After the BSF queries the B-TID, it calculates the derived key NAP specific keys of the Ks using the same algorithm as the UE side, and sends a successful response message to the NAF. The successful response includes the B-TID required by the NAF. The derived key NAF specific keys corresponding to the B-TID, and the expiration date set by the BSF for the key. After receiving the successful response message from the BSF, the NAF considers that the user is a legitimate user authenticated by the BSF, and the NAF and the UE share the key NAP specific keys derived from the Ks.

After that, the NAF and the UE perform encrypted communication through NAF specific keys in the subsequent communication process.

When the UE finds that Ks is about to expire, or the NAP requires the UE to re-authenticate to the BSF, The UE repeats the above steps to re-authenticate to the BSF to obtain a new shared key Ks and a derived key NAF specific keys.

It should be noted that for the GBA-ME process, the UE refers to a mobile device (ME, Mobile Equipment); if it is a GBA-U process, the above UE refers to a user identification module in a mobile device (UICC, Universal Integrated) Circuit Card ), the generated NAF specific keys described herein include two derived keys: Ks_int_NAF for the UICC and Ks_ext_NAF for the ME.

The above procedure is applicable to the case where the NAF client is in the UE, that is, the NAF client is on the ME of the UE, or on the UICC of the UE. However, with the increasing scope of application of the universal authentication framework, some new application scenarios have emerged. One of the larger application scenarios is the separation of the NAF client from the terminal. This situation refers to: A mobile user has multiple terminal devices, that is, in addition to the mobile phone, other terminal devices such as a PC, a WLAN UE, The handheld computer and the like, and these terminals use the same UICC (such as SIM card) user information to access the network service, so that the NAF client and the UE are not on the same device. The GAA architecture in this case is shown in Figure 2, which is referred to herein as the enhanced GAA framework. In this case, the NAF client is not on the UE, but on one or several peripheral devices other than the UE. When these peripheral terminal devices do not have the GBA function, the NAF client will be on the peripheral terminal device and not on the same device as the client executing GBA. The current GAA specification is mainly for the case where the NAF client and the GBA client are in the same terminal, and there is no authentication method for the GAA framework described in FIG.

Moreover, when a plurality of peripheral terminal devices share a GBA client on one UE, 'if two or some of the peripheral terminal devices access the same NAF, a plurality of peripheral terminal devices may also adopt the same derivative. When a key communicates with a certain NAF, it poses a security risk: If one of them is compromised, the other one will not break. Summary of the invention

In view of this, the main object of the present invention is to provide a key agreement method, system and device in an enhanced universal authentication framework to solve a GBA client in a UE, and a NAF client in a NAF client with other peripheral terminal devices. The end negotiates a key with the NAF to implement encrypted communication. An enhanced key agreement method in a universal authentication framework includes the following steps:

The peripheral terminal device requests a derivative key from the UE; the request carries a peripheral terminal device flag;

The UE calculates the first derived key according to the shared key Ks and the peripheral terminal device flag of the entity BSF that performs the user identity initial check verification, and provides the first derived key to the NAF client on the peripheral terminal device. ;

The network side calculates a second derived key according to the shared key Ks of the UE and the BSF and the obtained peripheral terminal device identifier, and saves the second derived key by the NAF. An enhanced key agreement method in a universal authentication framework includes the following steps:

The network side calculates a first derived key according to the shared key Ks of the entity BSF and the obtained peripheral terminal device identifier, which is performed by the UE and the user identity initial check verification, and saves the first derived key by the NAF;

The peripheral terminal device requests a derivative key from the UE, and the request carries a peripheral terminal device badge.

The UE calculates a second derived key according to its shared key Ks with the BSF and the peripheral terminal device flag, and provides the second derived key to the NAF client on the peripheral terminal device. A key agreement system in an enhanced universal authentication framework includes: More than one peripheral terminal device having a network service application entity NAF client requests a derived key from a UE connected thereto, and the request carries a peripheral terminal device flag;

The UE calculates a first derived key according to the shared key Ks of the entity BSF and the peripheral terminal device flag that performs initial authentication verification of the user identity, and provides the first derived key to the NAF client on the peripheral terminal device. End

The BSF calculates a second derived key according to its shared key Ks with the UE and the acquired peripheral terminal device flag, and provides the second derived key to the NAF. A key agreement system in an enhanced universal authentication framework includes:

More than one peripheral terminal device having a network service application entity NAF client requests a derived key from a UE connected thereto, and the request carries a peripheral terminal device flag;

The BSF calculates a temporary key according to the shared key Ks with the UE;

The NAF calculates a second derived key according to the temporary key and the obtained peripheral terminal device identifier, and saves the second derived key. A user terminal UE, connected to one or more peripheral terminal devices having a network service application entity NAF client, includes:

a key derivation module, configured to calculate a derived key according to a shared key Ks of the entity BSF with which the user identity initial verification is performed and a device identifier of the peripheral terminal device connected thereto, and provide the derived key to the peripheral terminal NAF client on the device. An execution user identity initial check verification entity BSF includes:

a key derivation module for acquiring and acquiring a shared key Ks from the user terminal UE A flag of the peripheral terminal device connected to the UE, calculating a derived key, and providing the derived key to the network service application entity NAF. A network side key derivation functional entity includes:

The first key derivation module is located in the execution user identity initial check verification entity BSF, and calculates the temporary key according to the shared key Ks of the BSF and the user terminal UE;

The second key derivation module is located at the network service application entity NAF, and calculates the derived key according to the temporary key calculated by the first key derivation module and the obtained device identifier of the peripheral terminal device connected to the UE. As can be seen from the foregoing technical solution, the present invention implements key negotiation between the NAF client and the NAF when the GBA client is at the UE and the NAF client is at another terminal.

Moreover, the present invention adopts the device identifier as one of the parameters for calculating the derived key, so different peripheral terminal devices use different derived keys to communicate with the same NAF, so that different peripheral terminal devices of the same UE can be prevented from adopting the same The security problem that exists when the derived key communicates with the NAF is that a peripheral terminal device is attacked, and other peripheral terminal devices may also be attacked. In the present invention, after the parameter for calculating the derived key is added to the device identifier identifying the peripheral terminal device of the different terminal, the derived key calculated for the different peripheral terminal device terminals is different, thereby improving the security.

On the other hand, the NAF client on the peripheral terminal device reports its own device flag to the NAF, which can not only calculate different derived keys for different terminal devices, but also make it possible to distinguish connection requests from different terminals of the same user. In this way, the access problem of multiple terminals of one user can be handled according to the local policy. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of the GAA frame. 2 is a schematic diagram of an enhanced GAA framework in a state where the NAF client and the GBA client are separated.

FIG. 3 is a flowchart of key negotiation between a NAF client and NAF communication in an enhanced GAA framework according to an embodiment of the present invention.

FIG. 4 is a flowchart of key negotiation for NAF client and NAF communication in an enhanced GAA framework according to another embodiment of the present invention.

FIG. 5 is a schematic diagram of a key agreement system for NAF client and NAF communication in an enhanced GAA framework according to an embodiment of the present invention.

FIG. 6 is a schematic diagram of a key agreement system for communicating NAF clients with NAF in an enhanced GAA framework according to another embodiment of the present invention.

FIG. 7 is a schematic diagram of a UE participating in key negotiation of a NAF client and NAF communication according to an embodiment of the present invention.

FIG. 8 is a schematic diagram of a BSF for key negotiation of a NAF client and NAF communication according to an embodiment of the present invention.

FIG. 9 is a schematic diagram of a network-side key derivation functional entity participating in key negotiation of a NAF client and NAF communication according to an embodiment of the present invention. Mode for carrying out the invention

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

FIG. 3 shows a GAA authentication procedure according to an embodiment of the present invention. In this embodiment, the UE and the peripheral terminal device belong to the same user. The following describes the secret key negotiation method of the NAF client and the NAF communication in the enhanced GAA framework, including the following steps:

Step 301: When the NAF client on the peripheral terminal device needs to use a certain service, send a connection request to the NAF corresponding to the service. If the NAF client knows that it needs to go to BSF To perform the mutual authentication process, you can skip this step and go directly to step 303.

Step 302: After receiving the request, the NAF searches whether the derived key corresponding to the user equipment is already stored, and if not, instructs the NAF client on the peripheral terminal device to communicate with the NAF client by using an encryption method, for example, indicating that the GAA key is used. In order to communicate securely, if there is already a valid derivative key shared by the NAF and the user equipment, the key communication is directly used, and the process ends.

Step 303: After receiving the indication, the NAF client on the peripheral terminal device requests the UE to use the derived key NAF specific keys to be used in the encrypted communication with the NAF, and carries the NAF identifier and the peripheral terminal device in the request message. Equipment sign.

Here, the device identifier refers to an identifier for distinguishing different peripheral terminal devices, and may be a device MAC address, an IP address, or a globally routable user agent universal resource identifier (GRUU, Globally Routable UA imi ), device identifier ( Similar to ME's IMEI) and so on. The peripheral terminal device can connect to the UE as a local interface through an interface such as a data line, USB, Bluetooth, or infrared to exchange messages. The device flag sent may also be an index value for the various identifiers listed above. Correspondingly, the UE stores the correspondence between each index and the identifier. After receiving the device index value, the UE obtains the real identifier according to the corresponding relationship.

It is worth noting that the device identifier is for distinguishing different peripheral terminal devices, that is, it may be a global device identifier, or may be a partial device identifier, such as a personal network element (PNE) defined in the personal network. , personal network element ) logo. The network side may also store the peripheral terminal device information of a certain UE, including the correspondence between the user identifier and each device owned by the UE.

Step 304: After receiving the request, the UE locally searches for a valid Ks. If there is a valid Ks, go directly to step 308; if there is no valid Ks, send an authentication request to the BSF to perform the GB A process.

Step 305: According to the GBA process, the BSF that receives the authentication request obtains the use by the HSS. User's authentication information.

Step 306: After obtaining the authentication information, the BSF performs mutual authentication and key agreement with the UE, and completes mutual authentication of the identity between the UE and the BSF and generation of the shared key Ks.

Step 307: The BSF may also define an expiration date for the Ks, and assign a session transaction identifier (B-TID) that can be used to identify the Ks to the UE. And after the Ks expires, return to step 304 to update Ks.

Step 308: The UE calculates a derived key according to Ks, and the calculation parameter includes a device identifier of the peripheral terminal device in addition to Ks, "gba-me" II RAKD II IMPI || NAFJD, thereby implementing different generation for different peripheral terminal devices. Derived key NAF specific keys. Specifically, it can be divided into:

When the UICC has the GBA function (belonging to the GBA-U process), the derived keys Ks_ext_NAF and Ks_int-NAF are calculated by the UICC. For example: Ks— ext— NAF = KF (Ks, "gba-me" || RAND || IMPI || NAF—Id||device flag); Ks— int— NAF = KDF (Ks, "gba-u" II RAND || IMPI || NAF—Id||Device Mark). Where RAND is a random number, IMPI refers to the user's IP multimedia private identity, NAF-ID refers to the NAF identifier, "gba-me" and "gba-u" represent the string; KDF is the abbreviation of the key derivation function.

When Ks is stored on the ME (belonging to the GBA-ME process), the derived key Ks-NAF is calculated by the ME, such as: Ks-NAF: KDF (Ks, "gba-me" || RAND || IMPI || NAP_Id| | Equipment logo).

It is also worth noting that the calculation of the NAF specific keys of the peripheral terminal device can also be carried out in two steps: In the first step, the Ks temporary derivative key is calculated according to the original calculated derivative key method (Ks-( Ext )—NAF—temp and Ks—int—NAF—temp represents): Ks—( ext )_NAFjemp=KDF(Ks ₅ "gba-me" ||RAND|| IMPI || NAF— Id) ; Ks—int— NAF— temp: KDF(Ks, "gba-u" || RAND || IMPI || NAF— Id); The second step is to calculate the derived key of the peripheral terminal device by the temporary derivative key: Ks—int/( Ext)_NAF =KDF(Ks_int/(ext)_NAF— temp, device flag).

Thus, if the peripheral terminal device and the NAF have the function of calculating a key, the second step of calculating the derived key can also be performed on the peripheral terminal device and the AF, and the UE and the BSF can respectively Ks_int/(ext)_ NAF_ temp is sent to the peripheral terminal device and NAF.

Step 309: The UE sends the calculated derivative key NAF specific keys and the B-TID of the identifier Ks to the NAF client on the peripheral terminal device through the local interface.

Step 310: The NAF client on the peripheral terminal device sends a connection request to the NAF again, and carries the B-TID and the device identifier in the request message.

It is worth pointing out that NAF may obtain the communication peripheral terminal equipment mark by other means. For example, the carrier network may locally configure the information that the peripheral terminal has been configured, and the peripheral terminal device or the UE tells the operator network (such as BSF or NAF) to enable a certain characteristic information of a peripheral terminal device by using a short message. The carrier network (such as BSF) finds the device flag locally and notifies NAF. It may also be a peripheral terminal device or a message that the UE directly tells the NAF peripheral terminal device through other messages. Alternatively, after receiving the request in step 304, the UE sends the peripheral terminal device identifier carried in the request to the network side. I won't go into details later.

Step 311: The NAF sends a key query message to the BSF for querying, and the query message carries the NAF identifier and the B-TID and the device identifier.

Step 312: After receiving the query message, the BSF searches for the corresponding key Ks according to the B-TID in the message, and calculates the derivative key according to the same algorithm as the UE side described in step 308 according to the B-TID, the device identifier, and the NAF identifier. key.

Step 313: The BSF returns the twin key NAF specific keys to the NAF along with the generated validity period of the key.

Step 314: After that, the NAF communicates with the peripheral terminal device using the derived key NAF specific keys. And after the derived key expires, return to step 308 to New derived key. Here, when the above process calculates the derived key NAF specific keys as Ks_ext_NAF and Ks_int-NAF, the NAF and the peripheral terminal can negotiate to select a derived key as the encrypted communication.

In addition, according to the device identifier, different peripheral terminal devices of a certain UE can be distinguished, and the feature can be used to control the number of peripheral terminal accesses of a certain UE to access a certain service according to the configuration policy. It can be configured and controlled by the BSF. The configuration policy can be sent to the NAF and controlled by the NAF. For example, the corresponding flag can be set in the USS (User Security Setting). After the operator configures it, it is sent by the BSF. ^ NAF, access control by NAF.

When the access control is performed, different peripheral terminal devices connected to the UE are distinguished according to the device identifier, and corresponding processing is performed according to the configured policy. For example, if only one peripheral terminal device connected to the UE is allowed to access the NAF at the same time (the entity implementing the NAF may be an application server AS), if it is found that there is a connection request sent by the other peripheral terminal device on the UE, or reject A new connection request either disconnects the old connection and accesses the new connection.

When performing access control, the BSF or NAF may also restrict whether the peripheral terminal device is allowed to access the network using the key calculated by the UE according to the peripheral terminal device flag.

As can be seen from the above, the present invention implements key negotiation between the NAF client and the NAF client by implementing the key agreement between the NAF client and the NAF client when the GBA client is in the UE, and the NAF client is in the other terminal. Moreover, in order to ensure sufficient security, when different peripheral terminal devices access the same NAF, different Ks specific keys are generated for the different peripheral terminal devices for the force. Confidential communication.

FIG. 4 shows a GAA authentication process of another embodiment of the present invention. The embodiment shown in FIG. 4 is different from the embodiment shown in FIG. 3 in that the NAF client on the peripheral terminal device sends a request message for querying Ks to the UE before instructing the UE to perform a GBA renegotiation process, and is in the query. After the absence of Ks or a valid Ks, the GBA negotiation process is carried out, A new negotiation Ks.

In this embodiment, both the UE and the peripheral terminal devices belong to the same user. The following describes the key negotiation method for NAF client and NAF communication under the enhanced GAA framework, including the following steps:

Step 401: When the NAF client on the peripheral terminal device needs to use a certain service, send a connection request to the NAF corresponding to the service. If the NAF client knows that it needs to go to the BSF to perform the mutual authentication process, it can skip this step and go directly to step 403.

Step 402: After receiving the request, the NAF searches whether the derived key corresponding to the user equipment is already stored. If not, the NAF client on the peripheral terminal device is instructed to communicate with the NAF client by using an encryption method, for example, indicating that the GAA key is used. In order to communicate securely, if there is already a valid derivative key shared by the NAF and the user equipment, the key communication is directly used, and the process ends.

Step 403: After receiving the indication, the NAF client on the peripheral terminal device sends a request for querying the Ks information to the UE. In order to know whether there is a valid Ks on the UE.

Step 404: After receiving the request, the UE locally searches for a valid Ks. If there is Ks, the B-TID of Ks is further sent to the peripheral terminal device together; if there is no Ks or the UE judges that Ks is invalid, then the B-TID is not returned (step 406 can be directly executed, In order to negotiate a Ks; it is also possible to send an indication to the peripheral terminal device that there is no valid key, and after receiving the GBA renegotiation indication of step 405, step 406 is performed.

Step 405: If the peripheral terminal device does not receive the B-TID corresponding to the Ks or judges that the received B-TID has expired according to the returned key validity period, the UE is instructed to perform a GBA renegotiation process. Otherwise, proceed to step 410.

It is worth noting that steps 403, 404, 405 can also be performed in the following manner: The peripheral device does not query whether the UE has a valid Ks, but sends a GBA indication directly to the UE. After receiving the GBA indication, the UE performs the same method according to the processing method after receiving the GBA indication of the NAF in the existing specification.

Step ⁴ 06: If no valid Ks exists, the UE sends an authentication request to the BSF to negotiate a Ks.

Step 407: According to the GBA process, the BSF that receives the authentication request obtains the authentication information of the user from the HSS.

Step 408: After obtaining the authentication information, the BSF performs mutual authentication and key agreement with the UE, and performs mutual authentication of the identity between the user and the BSF and generation of the shared key Ks.

Step 409: The BSF may also define an expiration date for the Ks, and allocate a B-TID that can be used to identify the Ks to be sent to the UE. And after the expiration of Ks, return to step 406 to update Ks.

Step 410: The peripheral terminal device requests the UE to use the derived key NAF specific keys to be used for the encrypted communication with the NAF, and carries the NAF identifier and the device identifier of the peripheral terminal device in the request message.

Step 411: The UE calculates the derived key according to Ks. The specific method of calculation is the same as step 308.

Step 412: The UE sends the calculated derivative key NAF specific keys and the B-TID of the identifier Ks to the NAF client on the peripheral terminal device through the local interface.

Step 413: The NAF client on the peripheral terminal device sends a connection request to the NAF again, and carries the B-TID and the device identifier in the request message.

Step 414: The NAF sends a key query message to the BSF for querying, and the query message carries the NAF identifier and the B-TID and the device identifier.

Step 415: After receiving the query message, the BSF searches for the corresponding key Ks according to the B-TID in the message, and calculates the derivative key according to the same algorithm as the UE side described in step 308 according to the B-TID, the device identifier, and the NAF identifier. key.

Step 416: The BSF will derive the key NAF specific keys along with the generated key The validity period is returned to NAF together.

Step 417: After that, the NAF communicates with the peripheral terminal device using the derived key NAF specific keys. And after the derived key expires, return to step 408 to update the derived key.

It is worth noting that steps 410-412 can be performed after 416.

The steps 408 to 417 are the same as the steps 306 to 314. The present invention also provides an enhanced key agreement system in a universal authentication framework. As shown in FIG. 5, in one embodiment, the system includes:

The UE calculates a first derived key according to the shared key Ks of the entity BSF and the peripheral terminal device flag that performs initial authentication verification of the user identity, and provides the first derivative key to the NAF client on the peripheral terminal device;

The BSF calculates a second derived key identical to the first derived key according to the shared key Ks with the UE and the acquired peripheral terminal device flag, and provides the second derived key to the NAF.

Therefore, in this embodiment, the second derivative key used by the NAF is separately calculated by the BSF on the network side. The peripheral terminal device flag used by the BSF to calculate the second derived key may be reported by the UE or may be obtained from the NAF. As shown in FIG. 6, in another embodiment of 4t, the system includes:

The UE calculates a first derived key according to the shared key Ks of the entity BSF and the peripheral terminal device flag that performs initial authentication verification of the user identity, and provides the first derived key to the peripheral terminal. a backup NAF client;

The BSF calculates a temporary key according to the shared key Ks with the UE;

NAF calculates a second derived key identical to the first derived key according to the temporary key and the acquired peripheral terminal device flag, and saves the second derived key.

Therefore, in this embodiment, the second derivative key used by the NAF is jointly calculated by the BSF and the NAF on the network side. The peripheral terminal device identifier used by the NAF to calculate the second derived key may be obtained from a connection request sent by the NAF client, or may be reported by the UE. The present invention also discloses a UE. As shown in FIG. 7, the UE is connected to one or more peripheral terminal devices having a NAF client, and includes a key derivation module for performing an entity BSF according to an initial check verification with a user identity. The shared key Ks and the device flag of the peripheral terminal device connected thereto calculate the derived key, and provide the derived key to the NAF client on the peripheral terminal device. The present invention also discloses a BSF for generating a derivative key by means of a BSF on the network side. As shown in FIG. 8, in this case, the BSF includes a key derivation module for calculating a derived key according to its shared key Ks with the user terminal UE and the acquired identifier of the peripheral terminal device connected to the UE. And provide the derived key to the network service application entity NAF. The invention also discloses a network side key derivation function entity, which is used for jointly generating a derivative key by the BSF and the NAF on the network side. As shown in FIG. 9, in this case, the key derivation function entity includes a first key derivation module located on the BSF and a second key derivation module located on the NAF. The first key derivation module is configured to calculate a temporary key according to the shared key Ks of the BSF and the user terminal UE; the second key derivation module is configured to use the temporary key and the calculated key according to the first key derivation module. Obtained peripheral terminal device connected to the UE The prepared device flag calculates the derived key.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

Claim

1. An enhanced key agreement method in a universal authentication framework for an encrypted communication between a network service application entity NAF and a client located on a peripheral terminal device, the method comprising:

The peripheral terminal device requests a derivative key from the UE, where the request carries a peripheral terminal device identifier;

The network side calculates a second derived key according to the shared key Ks of the UE and the BSF and the obtained peripheral terminal device identifier, and saves the second derived key by the NAF.

The method according to claim 1, wherein before the peripheral terminal device requests the derived key from the UE, the method further includes:

The NAF client sends a connection request to the NAF through the peripheral terminal device;

After receiving the connection request, the NAF instructs the peripheral terminal device to perform key agreement for performing the encrypted communication when it finds that the derived key for the encrypted communication is not stored.

The method according to claim 1, further comprising: when the first or second derived key exceeds an expiration date, or after the shared key Ks is updated, re-executing generating the first and second derived secrets The process of the key.

The method according to claim 1 or 3, wherein the shared key Ks of the UE and the BSF is a shared key generated by the UE and the BSF performing a mutual authentication GBA process.

5. The method according to claim 1, further comprising:

The UE provides the peripheral terminal device with a session transaction identifier B-TID that can be used to identify the shared key Ks, and sends the session transaction identifier to the network side through the peripheral terminal device; The network side determines the shared key Ks according to the session transaction identifier B-TID.

The method according to claim 1, wherein the network side calculates the second derived key as: calculating, by the BSF on the network side, the second derived key.

The method according to claim 1, wherein the calculating, by the network side, the second derived key comprises: calculating, by the BSF, the temporary key according to the shared key Ks, and then using the NAF according to the temporary secret The key and the peripheral terminal device flag calculate the second derived key.

The method according to claim 6 or 7, wherein, in the process of calculating Ks, the following parameters are also used for calculation: a random number RAND, a user's IP multimedia private identity identifier IMPI, the NAF identifier, A specific string.

The method according to claim 1, wherein the peripheral terminal device flag is one of the following:

The MAC address of the peripheral terminal device, the IP address, the globally routable user agent common resource identifier GRUU, the device identifier, and the index values of the above-mentioned respective identifiers.

10. The method according to claim 1, wherein the step of acquiring the peripheral terminal device flag comprises:

When the peripheral terminal device sends a connection request to the NAF on the network side, the connection request carries the peripheral terminal device identifier;

The network side acquires the peripheral terminal device flag from the connection request.

The method according to claim 1, wherein the acquiring the peripheral terminal device flag comprises: sending, by the UE, the peripheral terminal device identifier carried in the received request to the network side.

12. The method according to claim 1, further comprising: the BSF or the NAF identifying a connection request from a different peripheral terminal device of a certain user according to the peripheral terminal device flag, and controlling the user to perform according to the connection The number of different peripheral terminal devices connected to the same service. The method according to claim 1, wherein before the peripheral terminal device requests the derived key from the UE, the method further includes:

The peripheral terminal device sends a B-TID request to the UE to query whether the UE has a valid Ks. The peripheral terminal device receives the query result returned by the UE. If the query result is that the UE does not have a valid Ks, the UE is instructed to initiate the GBA process and negotiate a new one. Ks.

The method according to claim 1, wherein before the UE calculates the first derived key, further comprising,

XJE queries whether there is a valid Ks in the local. If the query result is that there is no valid Ks locally, a new GBA process is initiated to negotiate a new Ks.

15. An enhanced key agreement method in a universal authentication framework for use in an encrypted communication between a network service application entity NAF and a client located on a peripheral terminal device, the method comprising:

The UE calculates a second derived key according to the shared key Ks of the UE and the BSF and the peripheral terminal device flag, and provides the second derived key to the NAF client on the peripheral terminal device.

The method according to claim 15, wherein before the calculating, by the network side, the first derivative key, the method further comprises:

The method according to claim 15, wherein the calculating, by the network side, the first derived key comprises: calculating, by the BSF, the first derived key.

The method according to claim 15, wherein the calculating, by the network side, the first derivative key comprises: calculating, by the BSF, the temporary key according to the shared key Ks, and then using the NAF according to the temporary secret The key and the peripheral terminal device flag calculate the first derived key.

19. A key agreement system in an enhanced universal authentication framework, comprising: one or more peripheral terminal devices having a network service application entity NAF client, requesting a derived key from a UE connected thereto, the request carrying Peripheral terminal equipment mark;

UE, according to its shared key with the entity BSF that performs the initial check verification of the user identity

Ks and the peripheral terminal device flag calculate a first derived key, and provide the first derived key to the NAF client on the peripheral terminal device;

The BSF calculates a second derived key according to the shared key Ks with the UE and the obtained peripheral terminal device identifier, and provides the second derived key to the NAF;

NAF, saving the second derivative key.

20. A key agreement system in an enhanced universal authentication framework, comprising: more than one peripheral terminal device having a network service application entity NAF client, requesting a derived key from a UE connected thereto, the request carrying Peripheral terminal equipment mark;

The BSF calculates a temporary key according to the shared key Ks with the UE;

NAF, calculating the second derivative according to the temporary key and the acquired peripheral terminal device flag Generate a key and save the second derived key.

A user terminal UE, which is connected to one or more peripheral terminal devices having a network service application entity NAF client, and includes:

a key derivation module, configured to calculate a derived key according to a shared key Ks of the entity BSF with which the user identity initial verification is performed and a device identifier of the peripheral terminal device connected thereto, and provide the derived key to the peripheral terminal NAF client on the device.

An entity user initial check verification entity BSF, comprising: a key derivation module, configured to use the shared key Ks with the user terminal UE and the obtained peripheral terminal device connected to the UE The flag calculates the derived key and provides the derived key to the network service application entity NAF.

A network-side key-derived functional entity, comprising:

The second key derivation module is located at the network service application entity NAJF, and calculates the derived key according to the temporary key calculated by the first key derivation module and the obtained device identifier of the peripheral terminal device connected to the UE.