Message transmission method and device and related equipment

Abstract

The invention discloses a message transmission method and device and related equipment, and relates to the technical field of wireless communication. A sending device generates a first message and sends the first message to a receiving device. The first message is a data frame message or a management frame message, the first message comprises a first message header in a media access control protocol data unit (MPDU) format and first integrity protection information, and the first integrity protection information is used for performing integrity verification on the first message header. The data frame message or the management frame message sent by the sending device to the receiving device carries the first integrity protection information, and the first integrity protection information is used for protecting the integrity of the message header of the data frame message or the management frame message, so that important information carried in the message header can be prevented from being tampered by an attacker.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to a message transmission method, device and related equipment. Background Art

[0002] With the development of wireless communication technology, more and more wireless communication devices support multi-link communication. Devices supporting multi-link communication can be called multi-link devices (MLD). Each multi-link device has multiple radio frequency modules, and two multi-link devices can communicate through multiple communication links.

[0003] Data that needs to be protected can be transmitted between two multi-link devices through messages in the medium access control protocol data unit (MAC protocol data unit) format. The medium access control protocol data unit can be called a MAC protocol data unit (MAC protocol data unit, MPDU).

[0004] Since the message header of the message in the MPDU format carries important information, the industry has not yet provided a corresponding solution on how to protect the integrity of the message header of the message in the MPDU format. Summary of the invention

[0005] The present application provides a message transmission method, a sending device and a receiving device, which are used to protect the integrity of a message header of a message in an MPDU format.

[0006] In a first aspect, the present application provides a message transmission method, which is executed by a sending device, and the method may include: generating a first message, and sending the first message to a receiving device. The first message is a data frame message or a management frame message, and the first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information; the first integrity protection information is used to perform integrity check on the first message header.

[0007] The message transmission method provided in the embodiment of the present application carries first integrity protection information in the data frame message or management frame message sent by the sending device to the receiving device. The first integrity protection information is used to protect the integrity of the message header of the data frame message or the management frame message, thereby preventing important information carried in the message header from being tampered with by an attacker.

[0008] In an optional implementation manner, the first message is a unicast data frame message or a unicast management frame message, and the first integrity protection information is generated according to a control pairwise transient key CPTK of the unicast control frame message.

[0009] In the above implementation, the CPTK of the unicast control frame message is reused as the secret key of the unicast data frame message or the unicast management frame message, which can reduce the derivation and maintenance of the secret key and reduce the processing complexity when the sending device generates the first integrity protection information.

[0010] In another optional implementation, the first message is a multicast data frame message or a multicast management frame message, and the first integrity protection information is generated according to a control group temporary key CGTK of the multicast control frame message.

[0011] In the above implementation, the CGTK of the unicast control frame message is reused as the secret key of the multicast data frame message or the multicast management frame message, which can reduce the derivation and maintenance of the secret key and reduce the processing complexity when the sending device generates the first integrity protection information.

[0012] In an optional implementation, the first message further includes a first information indicator bit, wherein the first information indicator bit is used to indicate that the first message carries first integrity protection information, so that the receiving device verifies the first message header based on the first integrity protection information.

[0013] In an optional implementation manner, the first information indicator bit is a reserved bit in a Cipher Block Chaining Message Authentication Code Protocol frame header CCMP Header field of the first message.

[0014] In an optional implementation, the first integrity protection information includes a packet sequence number PN; if the first message is a retransmitted message, the PN in the first integrity protection information is configured according to the rule of increasing packet sequence numbers, so that the receiving device can determine whether the first message is a message replayed by an attacker based on the PN, thereby preventing replay attacks.

[0015] In an optional implementation, the sending device may also generate a second message and send the second message, wherein the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit, and the second information indicator bit is used to indicate that the second message carries the second integrity protection information.

[0016] In the above implementation, the second integrity protection information is added to the control frame message, and the second information indicator bit is set. Regardless of the control frame message, integrity protection can be performed to prevent important information carried in the control frame message from being tampered with by attackers.

[0017] In an optional implementation manner, the second information indicator bit is a designated field in a message header of the second message; or, the second information indicator bit is a reserved bit in a block acknowledgement request control BAR control field of the second message.

[0018] In a second aspect, the present application provides a message transmission method, which is executed by a receiving device, and the method may include: receiving a first message sent by a sending device; the first message is a data frame message or a management frame message, and the first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information; based on the first integrity protection information, performing an integrity check on the first message header.

[0019] In an optional implementation, the method may further include:

[0020] Receive a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; based on the second integrity protection information, perform an integrity check on the second message.

[0021] In a third aspect, the present application provides a message transmission method, which is performed by a sending device, and the method may include:

[0022] Generate a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information;

[0023] Send the second message.

[0024] In an optional implementation manner, the second information indicator bit is a designated field in a message header of the second message; or, the second information indicator bit is a reserved bit in a block acknowledgement request control BAR control field of the second message.

[0025] In a fourth aspect, the present application provides a message transmission method, which is performed by a receiving device, and the method may include:

[0026] receiving a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information;

[0027] Based on the second integrity protection information, an integrity check is performed on the second message.

[0028] In a fifth aspect, an embodiment of the present application provides a sending device, comprising a module for executing any one of the methods provided in the first aspect, or a module for executing any one of the methods provided in the third aspect.

[0029] In a sixth aspect, an embodiment of the present application provides a receiving device, comprising a module for executing any one of the methods provided in the second aspect, or a module for executing any one of the methods provided in the fourth aspect.

[0030] In the seventh aspect, an embodiment of the present application provides a sending device, including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the computer program is executed by the processor, the processor implements any one of the methods provided in the first aspect or the third aspect.

[0031] In an eighth aspect, an embodiment of the present application provides a receiving device, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the computer program is executed by the processor, the processor implements any one of the methods provided in the second aspect or the fourth aspect.

[0032] In the ninth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute any one of the methods provided in the first, second, third or fourth aspects above.

[0033] In a tenth aspect, an embodiment of the present application provides a computer program product comprising computer executable instructions, which are used to enable a computer to execute any one of the methods provided in the first, second, third or fourth aspects above.

[0034] The technical effects that can be achieved in any of the second to tenth aspects mentioned above can refer to the description of the beneficial effects in the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A network architecture diagram of a wireless communication system provided in an embodiment of the present application;

[0036] Figure 2 An interaction diagram between a sending device and a receiving device during a message transmission process provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a message format of a data frame message or a management frame message;

[0038] Figure 4 A schematic diagram of a message format of a data frame message or a management frame message provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of a message format of a frame control field provided in an embodiment of the present application;

[0040] Figure 6 A schematic diagram of a CCMP frame header message format provided in an embodiment of the present application;

[0041] Figure 7 A flowchart of a first message generation process provided in an embodiment of the present application;

[0042] Figure 8 A flowchart of a receiving device processing a first message provided in an embodiment of the present application;

[0043] Fig. 9 A schematic diagram of the correspondence between a key and a message type provided in an embodiment of the present application;

[0044] Fig.10 A schematic diagram of another correspondence between a key and a message type provided in an embodiment of the present application;

[0045] Fig.11 Another diagram of interaction between a sending device and a receiving device during a message transmission process provided in an embodiment of the present application;

[0046] Fig.12 A schematic diagram of a message format of a control frame message provided in an embodiment of the present application;

[0047] Fig.13 A structural block diagram of a sending device provided in an embodiment of the present application;

[0048] Fig.14 A structural block diagram of a receiving device provided in an embodiment of the present application;

[0049] Fig.15 A schematic diagram of the structure of a sending device provided in an embodiment of the present application;

[0050] Fig.16 A schematic diagram of the structure of a receiving device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. The terms used in the implementation method section of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0052] Before introducing the specific solutions provided by the embodiments of the present application, some terms in the present application are explained to facilitate understanding by those skilled in the art, and the terms in the present application are not limited.

[0053] (1) Data frame message: A message used to transmit data can be called a data frame message. Data frame messages can include unicast data frame messages and multicast data frame messages. The destination address of a unicast data frame message is a single target, that is, the receiving device of a unicast data frame message is uniquely determined. Multicast means that a sending device sends the same message to multiple receiving devices. The destination address of a multicast data frame message is a multicast address, and the multicast address points to multiple receiving devices belonging to a group.

[0054] (2) Management frame message: A message used to transmit management information between an access point device and a station device can be called a management frame message. Management frame messages can include unicast management frame messages and multicast management frame messages.

[0055] (3) Control frame message: A message used to transmit control signaling to assist data transmission can be called a control frame message. For example, a message used to transmit wake-up signaling, etc. Control frame messages can include unicast control frame messages and multicast control frame messages.

[0056] In the embodiments of the present application, "multiple" refers to two or more than two. In view of this, in the embodiments of the present application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, for example, one, two or more. For example, including at least one means including one, two or more, and there is no restriction on which ones are included. For example, including at least one of A, B and C, then A, B, C, A and B, A and C, B and C, or A and B and C may be included. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / ", unless otherwise specified, generally indicates that the previously associated objects are in an "or" relationship.

[0057] Unless otherwise specified, the ordinal numbers such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects and are not used to limit the order, timing, priority or importance of the multiple objects.

[0058] The message transmission method provided in the embodiment of the present application can be applied to a wireless communication network, for example, can be applied to a wireless local area network. Figure 1 A network architecture diagram of a wireless communication network is shown, such as Figure 1As shown, the wireless communication network may include an access point multi-link device (AP MLD) 100 and a non-access point multi-link device (non-AP MLD) 200. Figure 1 Only one AP MLD and one non-AP MLD are shown in the figure. In other embodiments, the wireless communication network may include multiple AP MLDs and multiple non-AP MLDs.

[0059] Among them, non-AP MLD200 can be a station (STA) multi-link device, such as a base station device. The base station device can be understood as a device deployed in a wireless access network to provide wireless communication functions for terminals. For example, it can be a base station (gNodeB or gNB) that meets the 5G standard. Among them, gNB can include various forms of macro base stations, micro base stations (also called small stations), relay stations, access points, wearable devices, and vehicle-mounted devices. gNB can also be a transmission and reception point (TRP) and a transmission measurement function (TMF). The gNB may include a central unit (CU) and a distributed unit (DU) integrated on the gNB.

[0060] AP MLD100 can be a user terminal device, for example, a wireless modem, or a mobile station (MS) connected to a wireless modem, a subscriber unit, a cellular phone, a smart phone, a wireless data card, a personal digital assistant (PDA) computer, a tablet computer, a wireless modem, a handset, a laptop computer, a machine type communication (MTC) terminal, etc.

[0061] Each AP MLD may include multiple radio frequency modules, for example, AP MLD100 may include radio frequency modules AP0 and AP1, and each non-AP MLD may include multiple radio frequency modules, for example, non-AP MLD200 may include radio frequency modules STA0 and STA1. The communication link formed between radio frequency module AP0 and radio frequency module STA0 may be referred to as link0, and the communication link formed between radio frequency module AP1 and radio frequency module STA1 may be referred to as link1, that is, the communication link between AP MLD100 and non-AP MLD200 includes at least link0 and link1. In other words, multi-link devices in a wireless communication network may communicate with each other through multiple communication links. Each communication link corresponding to each multi-link device has its own MAC address in the lower MAC (LMAC) sublayer of MLD, and the MAC address corresponding to each communication link may be referred to as a link address. In addition, each multi-link device also has a MAC address in the upper MAC (UMAC) sublayer of MLD, and the MAC address corresponding to the multi-link device may be referred to as an MLD MAC address.

[0062] The multi-link devices can transmit the data to be protected through the message in MPDU format. To ensure the integrity of the message header in MPDU format, the embodiment of the present application provides a message transmission method. Figure 2 The figure shows a flow chart of interaction between a sending device and a receiving device during message transmission. Both the sending device and the receiving device are multi-link devices. For example, the sending device may be Figure 1 The receiving device can be the AP MLD100 shown in FIG. Figure 1 The non-APMLD 200 shown in FIG. 200; alternatively, the sending device may be Figure 1 The non-AP MLD200 shown in the figure, the receiving device can be Figure 1 The AP MLD100 shown in FIG. Figure 2 As shown, the message transmission process may include the following steps:

[0063] S201, the sending device generates message A.

[0064] Among them, message A can be a unicast data frame message or a unicast management frame message. For example, when a sending device needs to send data to a receiving device, a unicast data frame message can be generated; when a sending device needs to send management information to a receiving device, a unicast management frame message can be generated. Message A can also be a retransmitted unicast data frame message or a unicast management frame message, and the unicast data frame message or the unicast management frame message can be a message in MPDU format.

[0065] The message format of the unicast data frame message or unicast management frame message in the related art is as follows: Figure 3 As shown, it may include a MAC frame header, a frame body, and a frame check sequence (FCS). Among them, the frame body is used to carry data or management information to be transmitted, and the FCS is used to check the data or management information. The MAC frame header can be called a message header in the MPDU format. The MAC frame header may include the following fields: frame control, duration, address 1, address 2, address 3, sequence control, QoS control, and HT control. The address 1 field is used to indicate the receiving address (receiver address, RA), that is, the link address corresponding to the receiving device. The address 2 field is used to indicate the sending address (transmitter address, TA), that is, the link address corresponding to the sending device. In the case of a non-aggregate MAC service data unit (MSDU), the address 3 field is used to indicate the address of the MLD associated with the receiving end, that is, the MLD MAC address of the receiving device; or, in the case of an aggregated MSDU, the address 3 field is used to indicate the link address associated with the receiving end, such as the link address corresponding to the AP0 of the receiving device. For unicast management frame messages, the address 3 field can be used for frame filtering. For example, according to address 3, it can be known whether the frame belongs to the basic service set (BSS). If not, the receiving device can discard the frame. Sequence control, QoS control and HT control are all control fields. The QoS control field may include a traffic identifier (TID) subfield and an MSDU present (A-MSDUpresent) subfield. The sequence control field may include two subfields: fragment number and sequence number.

[0066] In some embodiments, the message format of the unicast data frame message or the unicast management frame message carrying integrity protection information, that is, the message format of message A is as follows: Figure 4 As shown, the following fields may be included: MAC frame header (MAC header), cipher-block chaining message authentication code (CBC-MAC) protocol (CCMP) frame header (header), integrity protection information, protocol data unit (PDU), message integrity code (MIC) and frame check sequence (FCS). Among them, PDU is used to carry data or management information to be transmitted, and FCS is used to check the data or management information. The MAC frame header and CCMP frame header can be called MPDU format message headers, that is, the MPDU format message header can include a MAC frame header and a CCMP frame header. Among them, the structure of the MAC frame header can refer to Figure 3 The structure of the MAC frame header.

[0067] The frame control field in the MAC frame header is as follows Figure 5 As shown, the following subfields may be included: protocol version, type, subtype, to DS, from DS, more fragments, retry, power management, more data, protected frame, and whether HT control exists (+HTC). The protocol version subfield occupies two bits to indicate the network transmission protocol version applicable to the frame. For example, the protocol version may be IEEE802.1X. The type subfield occupies two bits, and the subtype subfield occupies four bits. The type and subtype are used to indicate the type of the frame, for example, whether the frame is a unicast data frame message, a multicast data frame message, or a unicast management frame message. The to DS subfield and the from DS subfield each occupy one bit to indicate whether the current device is a sending device or a receiving device. Whether more fragments, retry, power management, more data, protected frame, and HT control exist, these subfields each occupy one bit. More Fragments is used to indicate whether there are other fragments associated with the frame, More Data is used to indicate whether there is other data associated with the frame. Retry is used to indicate whether the frame is a retransmitted message.

[0068] In some embodiments, Figure 6 As shown in FIG. 1 , the CCMP frame header may include a packet number (PN) and a key information (Key ID) field. The PN length is 6 bytes, corresponding to PN0-PN5 from low byte to high byte. The key information field occupies one byte, the ExtIV bit in the byte is always set to 1, and Bit 6-7 in the byte is the Key ID subfield, which can carry a key identifier to indicate the key used, and the other bits are reserved bits.

[0069] The third byte of the CCMP frame header field is a reserved byte. In some embodiments, message A may also include an information indicator bit a, and the information indicator bit a is used to indicate that message A carries integrity protection information a. The information indicator bit a may be a reserved byte in the CCMP frame header field of message A or a reserved bit in a reserved bit. For example, when the reserved bit is in the 1 position, it indicates that integrity protection information a exists; when the reserved bit is in the 0 position, it indicates that integrity protection information a does not exist. In other embodiments, the information indicator bit a may be carried in the MAC frame header, for example, Figure 4 The subtype subfield in the MAC frame header shown is set to a new value, which is used to indicate that message A is a message in an enhanced protected MPDU frame format, that is, message A contains integrity protection information a to protect the MPDU message header.

[0070] The integrity protection information field is used to carry integrity protection information a. Key ID+PN+MIC can be called integrity protection information a, which is used to perform integrity check on the message header in MPDU format. The message header in MPDU format can be referred to as MPDU message header. Exemplarily, the integrity protection information a can be additional authentication data (AAD) in the MPDU message header. In the frame control field of the MPDU message header, except for the lower 3 bits of the Subtype subfield, the Retry subfield, the Power management subfield, the More Data subfield, the Protected frame subfield and the +HTC subfield, all other subfields belong to AAD. The Duration field is not protected, and the Sequence Number subfield in the Sequence Control field is not protected. That is to say, the Protocol version subfield, Type subfield, To DS subfield, From DS subfield, More fragments subfield in the frame control field, as well as the Address1 field, Address2 field, Address3 field, Fragment Number subfield in the Sequence Control field, and TID subfield in the QoS control field (the above fields or subfields belong to the MAC frame header) all belong to AAD and are protected.

[0071] In some embodiments, the MAC layer of the multi-link device can be divided into a UMAC sublayer and an LMAC sublayer. The integrity protection of the message header in the MPDU format can be deployed in the LMAC sublayer of the MAC layer. Figure 7 As shown, the sending device performs the following steps:

[0072] S701: Create an MPDU message header for message A.

[0073] S702: Perform integrity protection operation on the MPDU message header.

[0074] For the sending device, after the LMAC layer of the sending device creates the MPDU message header for message A, it performs the integrity protection operation of the MPDU message header. Among them, Key ID indicates the key identifier used, and PN is the packet sequence number assigned to the MPDU. PN can be used by the receiving end to detect replay attacks. The MIC is determined according to the protected information, Key and PN, wherein the protected information may include part or all of the following fields: Protocol version subfield, Type subfield, To DS subfield, From DS subfield, More fragments subfield, Retry subfield, PowerManagement subfield, More Data subfield, protected frame subfield, +HTC subfield, Address1 field, Address2 field, Address3 field, Sequence Control field and QoS control field, CCMP frame header field; MIC is obtained by performing calculations based on the protected information, Key and PN. Key ID+PN+MIC can be called integrity protection information a.

[0075] In the related art, the PN of the retransmitted message is usually consistent with the initial transmission message, and does not follow the rule of increasing the packet sequence number. In the embodiment of the present application, in order to prevent replay attacks, even if the message A is a retransmitted message, the PN in the integrity protection information a is configured according to the rule of increasing the packet sequence number, that is, the PN also needs to be increased to maintain a strict increase of the PN.

[0076] In some embodiments, a set of pairwise transient keys (PTK) can be set separately. The pairwise transient key can be called XPTK. XPTK is used to protect the message header of the MPDU format of the unicast data frame message or the unicast management frame message. The LMAC layer of the sending device can use the identifier of the XPTK as the Key ID. In an optional embodiment, multiple XPTKs are stored in the sending device. Each communication link between the sending device and the receiving device corresponds to an XPTK, and the identifier of the XPTK corresponding to each communication link can be different. The sending device can determine the corresponding XPTK identifier based on the communication link corresponding to the message A, and use the determined XPTK identifier as the Key ID.

[0077] In other embodiments, considering that the unicast control frame message has a control pairwise transient key (CPTK), the CPTK of the unicast control frame message can be reused, that is, the CPTK is used to protect the unicast control frame message, and can also be used to protect the unicast data frame message and the unicast management frame message. The LMAC layer of the sending device can use the identifier of the CPTK as the Key ID. In an optional embodiment, multiple CPTKs are stored in the sending device. Each communication link between the sending device and the receiving device corresponds to a CPTK, and the identifier of the CPTK corresponding to each communication link is different. The sending device can determine the corresponding CPTK identifier based on the communication link corresponding to the message A, and use the determined CPTK identifier as the Key ID.

[0078] Reusing the CPTK of the unicast control frame message as the secret key for the unicast data frame message and the unicast management frame message can reduce the derivation and maintenance of the secret key and reduce the processing complexity of the LMAC layer.

[0079] S703: Create a cyclic redundancy check.

[0080] The sending device may calculate a cyclic redundancy check (CRC) to obtain an FCS.

[0081] S704, MPDU aggregation process.

[0082] The sending device may aggregate multiple messages A.

[0083] S202: The sending device sends message A to the receiving device.

[0084] The sending device may send the MPDU obtained by aggregating multiple messages A to the receiving device.

[0085] S203: The receiving device performs an integrity check on the message header a based on the integrity protection information a.

[0086] In some embodiments, after receiving the MPDU after the aggregation of multiple messages A, the processing process of the aggregated MPDU can refer to the following. Figure 8 As shown, the following steps are included:

[0087] S801, MPDU de-aggregation process.

[0088] The receiving device performs de-aggregation processing on the received aggregated MPDU to obtain one or the first message A.

[0089] S802, perform CRC check on message A.

[0090] The LMAC layer of the receiving device uses FCS to perform a CRC check on message A. If the check passes, it continues to perform an integrity check on the MPDU message header of message A. If the verification fails, message A is discarded.

[0091] S803: Perform integrity check on the MPDU header of message A.

[0092] The LMAC layer of the receiving device can obtain the Key according to the Key ID carried in the integrity protection information a, and calculate the MIC according to the protected information, the Key and the PN, that is, by calculating the Protocol version subfield, the Type subfield, the To DS subfield, the From DS subfield, the More fragments subfield, the Retry subfield, the Powermanagement subfield, the More Data subfield, the Protected frame subfield, the +HTC subfield, the Address1 field, the Address2 field, the Address3 field, the Sequence Control field and the QoS control field in the frame control field, part or all of the information in the CCMP frame header field, and the Key and the PN to obtain the MIC. If the calculated MIC is consistent with the MIC in the integrity protection information a, the verification is passed, and the replay attack detection of the message A continues; if the calculated MIC is inconsistent with the MIC in the integrity protection information a, the verification fails, and the message A is discarded.

[0093] S804: Perform replay attack detection on message A.

[0094] In some embodiments, the receiving device may maintain a replay counter for the received unicast message, and the replay counter stores the PN value of the most recently received unicast message. The receiving end compares the PN of message A with the current value in the replay counter. If the PN of message A is less than the current value in the replay counter, it indicates that it may be subject to a replay attack, and message A may be discarded.

[0095] S805, performing address 1 filtering and block scoreboard status update operations on message A.

[0096] If the above verification process is passed, the receiving device can continue to filter the address 1 of message A (address1filtering) and update the block scoreboard status (block ack scoreboarding). Among them, address 1 is the address of the receiving end. If the receiving end determines that it is not the target receiving end through address 1 carried in message A, it can discard message A. If the receiving end determines that it is the target receiving end, it can update the block scoreboard status.

[0097] In some embodiments, the sending device may also send a multicast data frame message or a multicast management frame message to the receiving device. Exemplarily, the sending device may perform step S204.

[0098] S204, the sending device generates message B.

[0099] Among them, message B can be a multicast data frame message or a multicast management frame message. For example, when the sending device needs to send data to the receiving device through multicast, a multicast data frame message can be generated; when the sending device needs to send management information to the receiving device through multicast, a multicast management frame message can be generated. Message B can also be a retransmitted multicast data frame message or a multicast management frame message, and the multicast data frame message or the multicast management frame message can be a message in the MPDU format.

[0100] In some embodiments, the format of the multicast data frame message or the multicast management frame message can refer to Figure 3 and Figure 5 For example, when the receiving device does not need to reorder the multicast frame message, it is not necessary to consider protecting the MPDU message header of the multicast data frame message or the multicast management frame message. At this time, the format of the multicast data frame message or the multicast management frame message can refer to Figure 3 If the MPDU header of a multicast data frame or a multicast management frame needs to be protected, the integrity protection information b can be carried in the multicast data frame or the multicast management frame. In this case, the format of the multicast data frame or the multicast management frame can refer to Figure 5 The message format is shown.

[0101] In some embodiments, a group temporal key (GTK) may be set separately, and the group temporal key may be called XGTK, and XGTK is used to protect the MPDU format message header of the multicast data frame message or the multicast management frame message. The LMAC layer of the sending device may use XGTK as the Key, and determine the MIC according to the protected information, Key and PN, wherein the protected information may include part or all of the following fields: the Protocol version subfield, Type subfield, To DS subfield, From DS subfield, Morefragments subfield, Retry subfield, Power Management subfield, More Data subfield, protectedframe subfield, +HTC subfield, Address1 field, Address2 field, Address3 field, SequenceControl field and QoS control field, CCMP frame header field in the frame control field of the multicast data frame message or the multicast management frame message. The MIC is obtained by performing calculations based on the protected information, Key and PN. The LMAC layer of the sending device may use the identifier of XGTK as the Key ID, and Key ID+PN+MIC may be called integrity protection information b.

[0102] In an optional embodiment, a plurality of XGTKs are stored in the sending device. Each communication link between the sending device and the receiving device corresponds to an XGTK, and the identifier of the XGTK corresponding to each communication link is different. The sending device can determine the identifier of the corresponding XGTK according to the communication link corresponding to the message B, and use the determined identifier of the XGTK as the KeyID.

[0103] In this embodiment, the corresponding relationship between the key and the message is as follows: Fig. 9 As shown in the figure: CPTK is used to protect unicast control frame messages (individually addressed control frame), CGTK is used to protect multicast control frame messages (groupaddressed control frame), XPTK is used to protect the MPDU message header of unicast data frame messages (individually addressed data frame) and unicast management frame messages (individually addressed management frame), and XGTK is used to protect the MPDU message header of multicast data frame messages (group addressed data frame) and multicast management frame messages (group addressed management frame).

[0104] In other embodiments, the control group transient key (CGTK) of the unicast control frame message can be reused, that is, the CGTK is used to protect both the multicast control frame message and the multicast data frame message and the multicast management frame message. The LMAC layer of the sending device can use the CGTK as the Key to determine the MIC according to the protected information, the Key and the PN, wherein the protected information can include part or all of the following fields: the Protocol version subfield, the Type subfield, the To DS subfield, the From DS subfield, the More fragments subfield, the Retry subfield, the Power Management subfield, the More Data subfield, the protected frame subfield, the +HTC subfield, the Address1 field, the Address2 field, the Address3 field, the Sequence Control field and the QoS control field, and the CCMP frame header field in the frame control field of the multicast data frame message or the multicast management frame message. The MIC is obtained by performing calculations based on the protected information, the Key and the PN. The LMAC layer of the sending device can use the identifier of the CGTK as the Key ID, and the Key ID+PN+MIC can be called the integrity protection information b. The LMAC layer of the sending device may use the identifier of the CGTK as the Key ID, that is, the integrity protection information b is generated according to the CGTK of the multicast control frame message.

[0105] In an optional embodiment, a plurality of CGTKs are stored in the sending device. Each communication link between the sending device and the receiving device corresponds to a CGTK, and the identifier of the CGTK corresponding to each communication link may be different. The sending device may determine the identifier of the corresponding CGTK according to the communication link corresponding to the message B, and use the determined CGTK identifier as the Key ID.

[0106] Reusing the CGTK of the multicast control frame message as the secret key of the multicast data frame message and the multicast management frame message can reduce the derivation and maintenance of the secret key and reduce the processing complexity of the LMAC layer.

[0107] In this embodiment, the corresponding relationship between the key and the message is as follows: Fig.10 As shown in the figure: CPTK is used not only to protect unicast control frame messages, but also to protect the MPDU message headers of unicast data frame messages and unicast management frame messages. CGTK is used not only to protect multicast control frame messages, but also to protect the MPDU message headers of multicast data frame messages and multicast management frame messages.

[0108] In some embodiments, the MAC frame header of the multicast data frame message or the multicast management frame message may also include an aggregated control (A-Control) field, which is 26 bits long. In order to enable the old receiving device to correctly receive the multicast data frame message or the multicast management frame message, the integrity protection information b "Key ID + PN + MIC" may also be carried in the A-Control field and carried with a newly defined control identifier. If the A-Control field length is not enough, one or more QoS Null frames may be aggregated and multiple A-Control fields may be sequentially spliced ​​to carry "Key ID + PN + MIC".

[0109] In the related art, the PN of the retransmitted message is usually consistent with the initial transmission message, and does not follow the rule of increasing the packet sequence number. In the embodiment of the present application, in order to prevent replay attacks, even if the message B is a retransmitted message, the PN in the integrity protection information b is configured according to the rule of increasing the packet sequence number, that is, the PN also needs to be increased to maintain a strict increase in the PN.

[0110] In some embodiments, message B may further include an information indicator bit b, and the information indicator bit b is used to indicate that message B carries integrity protection information b. The information indicator bit b may be carried in a MAC frame header, or the information indicator bit b may be a reserved bit in a reserved byte or a reserved bit in a CCMP frame header field of message B.

[0111] S205: The sending device sends message B to the receiving device.

[0112] S206: The receiving device performs an integrity check on the message header b based on the integrity protection information b.

[0113] In some embodiments, after receiving message B, the receiving device may perform de-aggregation processing on message B and extract FCS and integrity protection information b from message B. The LMAC layer of the receiving device uses FCS to perform CRC check on message B. If the verification fails, message B is discarded. If the verification passes, the LMAC layer of the receiving device may obtain the Key according to the Key ID carried in the integrity protection information b, and calculate the MIC according to the protected information, Key and PN, that is, by calculating the Protocol version subfield, Type subfield, To DS subfield, From DS subfield, More fragments subfield, Retry subfield, Power Management subfield, More Data subfield, protected frame subfield, +HTC subfield, Address1 field, Address2 field, Address3 field, Fragment Number subfield and QoS control field in the Sequence Control field in the multicast data frame message or the multicast management frame message, part or all of the information in the CCMP frame header field, and Key and PN to obtain the MIC. If the calculated MIC is inconsistent with the MIC in the integrity protection information b, the verification fails and message B is discarded. If the calculated MIC is consistent with the MIC in the integrity protection information b, the verification passes, and the LMAC layer of the receiving device continues to perform replay attack detection on message B. In some embodiments, the receiving device can maintain a replay counter for the received multicast message, and the replay counter stores the PN value of the most recently received multicast message. The receiving end compares the PN of message B with the current value in the replay counter. If the PN of message B is less than the current value in the replay counter, it indicates that it may be subject to a replay attack and message B can be discarded. If the above verification processes are all passed, the receiving device can process message B normally.

[0114] In the above embodiment, the message headers of the data frame message and the management frame message are protected, so that the attacker may not tamper with the sequence number (SN) in the message header to move the scoreboard window WinStart_R of the receiving end and the window WinStart_B of the receiving reordering buffer, thereby causing a reception error; and if a wake-up request is carried in the message header, the receiving end may be prevented from being mistakenly awakened by the attacker, thereby consuming the energy of the receiving device.

[0115] In some embodiments, before sending a data frame message or a management frame message, a control frame message, such as a Trigger control frame message and a block ack request (BAR) control frame message, may be sent between the sending device and the receiving device. The control frame message may be a unicast control frame message or a multicast control frame message. The integrity protection information "Key ID+PN+MIC" of the control frame message may be carried in a User Info field starting with a special association identifier (AID). However, some control frames that need to be protected do not have a UserInfo field, such as a BAR control frame message. Based on this, an embodiment of the present application provides a message transmission method. Fig.11 FIG. 1 shows a flow chart of the interaction between the sending device and the receiving device in the message transmission method. Fig.11 As shown, the message transmission method may include the following steps:

[0116] S1101, the sending device generates message C.

[0117] The message C is a control frame message, and the message C may be a unicast control frame message or a multicast control frame message. For example, the message C may be a BAR control frame message.

[0118] In some embodiments, the message format of message C is as follows: Fig.12As shown, it may include a frame control field, a duration field, a received address (RA) field, a transmit address (TA), a BAR control field, a BAR information field, an integrity protection information (Key ID+PN+MIC) field and a frame check sequence (FCS) field. If message C is a unicast control frame message, the Key ID may be an identifier of the CPTK, and if message C is a multicast control frame message, the Key ID may be an identifier of the CGTK. In an optional embodiment, a plurality of CPTKs and a plurality of CGTKs are stored in the sending device. Each communication link between the sending device and the receiving device corresponds to a CPTK and a CGTK, and the identifiers of the CPTKs corresponding to each communication link may be different, and the identifiers of the CGTKs corresponding to each communication link may also be different. If message C is a unicast control frame message, the sending device can determine the corresponding CPTK identifier according to the communication link corresponding to message C, and use the determined CPTK identifier as the Key ID; if message C is a multicast control frame message, the sending device can determine the corresponding CGTK identifier according to the communication link corresponding to message C, and use the determined CGTK identifier as the Key ID.

[0119] In message C, the fields before the BAR information field can be called the message header of message C. The frame control field in the message header can occupy 2 bytes (octets). The structure of the frame control field can refer to Figure 4 The structure shown in FIG. 1 is a structure shown in FIG. 1. The frame control field includes a protected frame subfield. The duration field may occupy 2 bytes, the RA field and the TA field may occupy 6 bytes respectively, the BAR control field may occupy 2 bytes, the FCS field may occupy 4 bytes, and the length of the BAR information field may be variable, depending on the length of the control information to be carried.

[0120] In addition to the integrity protection information c, the message C may also include an information indication bit c, where the information indication bit c is used to indicate whether the message C carries the integrity protection information c.

[0121] In one embodiment, the information indication bit c may be a designated field in the message header of the message C, for example, the Protected Frame subfield in the frame control field may be multiplexed; when the Protected Frame subfield is set to 1, it indicates that the integrity protection information c exists; when the Protected Frame subfield is set to 0, it indicates that the integrity protection information c does not exist.

[0122] In another embodiment, the information indicator bit c may be a reserved bit in the BAR control field of message C; when the reserved bit is in position 1, it indicates that the integrity protection information c exists; when the reserved bit is in position 0, it indicates that the integrity protection information c does not exist.

[0123] S1102: The sending device sends message C to the receiving device.

[0124] S1103: The receiving device performs an integrity check on the message C based on the integrity protection information c.

[0125] In some embodiments, after the receiving device receives message C, the processing process of message C can be performed with reference to the processing process of message A and message B, which will not be repeated here.

[0126] Based on the same technical concept as the above embodiments, a sending device is also provided in the embodiments of the present application. The sending device can be used to implement the functions of any of the methods provided in the above embodiments, and thus can achieve the beneficial effects of the above method embodiments.

[0127] like Fig.13 As shown, the sending device 1300 may include a message generating module 1301 and a message sending module 1302. The sending device 1300 may be used to implement the functions of the method executed by the sending device in the above embodiment, and thus may achieve the beneficial effects of the above message transmission method embodiment.

[0128] In some embodiments, the message generation module 1301 can be used to generate a first message; the first message is a data frame message or a management frame message. The first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information, and the first integrity protection information is used to perform integrity check on the first message header. The message sending module 1302 can be used to send the first message to a receiving device.

[0129] In some implementations, the first message is a unicast data frame message or a unicast management frame message, and the first integrity protection information is generated based on a control pairwise transient key CPTK of the unicast control frame message.

[0130] In other implementations, the first message is a multicast data frame message or a multicast management frame message, and the first integrity protection information is generated according to a control group temporary key CGTK of the multicast control frame message.

[0131] In some implementations, the first message further includes a first information indicator bit; the first information indicator bit is used to indicate that the first message carries first integrity protection information.

[0132] In some implementations, the first information indicator bit is a reserved bit in a Cipher Block Chaining Message Authentication Code Protocol frame header CCMP Header field of the first message.

[0133] In some implementations, the first integrity protection information includes a packet sequence number PN; if the first message is a retransmission message, the PN in the first integrity protection information is configured according to a rule of increasing packet sequence numbers.

[0134] In some other embodiments, the message generation module 1301 can be used to generate a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information. The message sending module 1302 can be used to send the second message.

[0135] In some implementations, the second information indicator bit is a designated field in a message header of the second message; or, the second information indicator bit is a reserved bit in a block acknowledgement request control BAR control field of the second message.

[0136] Based on the same technical concept as the above embodiments, a receiving device is also provided in the embodiments of the present application. The receiving device can be used to implement the functions of any of the methods provided in the above embodiments, and thus can achieve the beneficial effects of the above method embodiments.

[0137] like Fig.14 As shown, the receiving device 1400 may include a message receiving module 1401 and a message processing module 1402. The receiving device 1400 may be used to implement the functions of the method executed by the receiving device in the above embodiment, and thus may achieve the beneficial effects of the above message transmission method embodiment.

[0138] In some embodiments, the message receiving module 1401 can be used to receive a first message sent by a sending device; the first message is a data frame message or a management frame message, and the first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information; the message processing module 1402 can be used to perform an integrity check on the first message header based on the first integrity protection information.

[0139] In other embodiments, the message receiving module 1401 can be used to receive a second message; the second message is a control frame message, and the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; the message processing module 1402 can be used to perform an integrity check on the second message based on the second integrity protection information.

[0140] Based on the same technical concept as the above embodiment, the present application also provides a sending device, which can be Figure 1 The AP MLD100 or non-AP MLD200 shown in FIG. The sending device can be used to implement the functions of the method executed by the sending device in the above embodiment, so the beneficial effects of the above method embodiment can be achieved.

[0141] In some embodiments, the structure of the sending device 1500 can be as follows: Fig.15 As shown, it includes a processor 1501 and a memory 1502 connected to the processor 1501. The processor 1501 and the memory 1502 can be interconnected via a bus, and the processor 1501 can serve as the main processor of the sending device 1500, that is, the control core of the sending device 1500. The bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The specific connection medium between the above-mentioned processor 1501 and the memory 1502 is not limited in the embodiments of the present application.

[0142] The memory 1502 may include the above-mentioned memory, and the memory 1502 may be a volatile memory, such as a random access memory; the memory may also be a non-volatile memory, such as a read-only memory ROM, a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), or the memory 1502 is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 1502 may be a combination of the above-mentioned memories. The memory 1502 may be used to store software programs and modules.

[0143] The processor 1501 may include one or more processors. The processor 1501 executes various functional applications and data processing of the sending device 1500 by running software programs and modules stored in the memory 1502, such as the message transmission method provided in the embodiment of the present application.

[0144] In some embodiments, the sending device 1500 may also include a communication module, such as Figure 1 The radio frequency module shown in the communication module can be used to communicate with other network elements in the network.

[0145] It is to be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the network device. In other embodiments of the present application, the network device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0146] Based on the same technical concept as the above embodiment, the present application also provides a receiving device, which can be Figure 1 The AP MLD100 or non-AP MLD200 shown in FIG. The receiving device can be used to implement the functions of the method executed by the receiving device in the above embodiment, so the beneficial effects of the above method embodiment can be achieved.

[0147] In some embodiments, the structure of the receiving device 1600 can be as follows Fig.16 As shown, it includes a processor 1601 and a memory 1602 connected to the processor 1601. The processor 1601 and the memory 1602 can be interconnected via a bus, and the processor 1601 can serve as the main processor of the receiving device 1600, that is, the control core of the receiving device 1600. The bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The specific connection medium between the above-mentioned processor 1601 and the memory 1602 is not limited in the embodiment of the present application.

[0148] The memory 1602 may include the above-mentioned memory, and the memory 1602 may be a volatile memory, such as a random access memory; the memory may also be a non-volatile memory, such as a read-only memory ROM, a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), or the memory 1602 is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 1602 may be a combination of the above-mentioned memories. The memory 1602 may be used to store software programs and modules.

[0149] The processor 1601 may include one or more processors. The processor 1601 executes various functional applications and data processing of the receiving device 1600 by running software programs and modules stored in the memory 1602, such as the message transmission method provided in the embodiment of the present application.

[0150] In some embodiments, the receiving device 1600 may also include a communication module, such as Figure 1 The radio frequency module shown in the communication module can be used to communicate with other network elements in the network.

[0151] It is to be understood that the structure illustrated in the embodiments of the present application does not constitute a specific limitation on the network device. In other embodiments of the present application, the network device may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0152] The method steps in the embodiments of the present application can be implemented by hardware, or by a processor executing a computer program or instruction. The computer program or instruction can constitute a computer program product. The embodiment of the present application also provides a computer program product, including computer executable instructions. In one embodiment, the computer executable instructions are used to enable a computer to perform the functions in the above method embodiments.

[0153] The computer executable instructions may be stored in a computer readable storage medium. The present application also provides a computer readable storage medium, wherein the computer readable storage medium stores the executable instructions. In one embodiment, the computer executable instructions are used to enable a computer to execute the functions in the above method embodiment.

[0154] The computer-readable storage medium provided in the embodiments of the present application may be a random access memory (RAM), a flash memory, a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a register, a hard disk, a mobile hard disk, a CD-ROM, or any other form of computer-readable storage medium known in the art.

[0155] Computer executable instructions may be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium. For example, the computer program or instructions may be transferred from one website, computer, server or data center to another website, computer, server or data center by wired or wireless means. The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; it may also be an optical medium, such as a digital video disc (DVD); it may also be a semiconductor medium, such as a solid state drive.

[0156] In each embodiment of the present application, if there is no special explanation and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced to each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, including a series of steps or units. Methods, systems, products or devices are not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0157] Although the present application has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, the present specification and the accompanying drawings are merely exemplary illustrations of the schemes defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present application.

[0158] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A message transmission method, characterized in that: Applied to a sending device, the method comprises: Generate a first message; the first message is a data frame message or a management frame message, the first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information; the first integrity protection information is used to perform integrity check on the first message header; Send the first message to a receiving device.

2. The method according to claim 1, characterized in that: The first message is a unicast data frame message or a unicast management frame message, and the first integrity protection information is generated according to a control pairwise transient key CPTK of a unicast control frame message.

3. The method according to claim 1, characterized in that: The first message is a multicast data frame message or a multicast management frame message, and the first integrity protection information is generated according to a control group temporary key CGTK of the multicast control frame message.

4. The method according to any one of claims 1 to 3, characterized in that The first message also includes a first information indicator bit; the first information indicator bit is used to indicate that the first message carries the first integrity protection information.

5. The method according to claim 4, characterized in that The first information indicator bit is a reserved bit in a Cipher Block Chaining Message Authentication Code Protocol frame header CCMP Header field of the first message.

6. The method according to any one of claims 1 to 5, characterized in that: The first integrity protection information includes a packet sequence number PN; if the first message is a retransmitted message, the PN in the first integrity protection information is configured according to a rule of increasing packet sequence numbers.

7. The method according to any one of claims 1 to 6, characterized in that: The method further comprises: Generate a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; the second integrity protection information is used to perform integrity check on the second message; Send the second message.

8. The method according to claim 7, characterized in that The second information indicator bit is a designated field in a message header of the second message; or, the second information indicator bit is a reserved bit in a block acknowledgement request control BARcontrol field of the second message.

9. A message transmission method, characterized in that: Applied to a receiving device, the method comprises: Receive a first message sent by a sending device; the first message is a data frame message or a management frame message, and the first message includes a first message header in a media access control protocol data unit MPDU format and first integrity protection information; Based on the first integrity protection information, an integrity check is performed on the first message header.

10. The method according to claim 9, characterized in that The method further comprises: receiving a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; Based on the second integrity protection information, perform an integrity check on the second message.

11. A message transmission method, characterized in that: Applied to a sending device, the method comprises: Generate a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; the second integrity protection information is used to perform integrity check on the second message; Send the second message to the receiving device.

12. The method according to claim 11, characterized in that The second information indicator bit is a designated field in a message header of the second message; or, the second information indicator bit is a reserved bit in a block acknowledgement request control BARcontrol field of the second message.

13. A message transmission method, characterized in that: Applied to a receiving device, the method comprises: receiving a second message; the second message is a control frame message, the second message includes second integrity protection information and a second information indicator bit; the second information indicator bit is used to indicate that the second message carries the second integrity protection information; Based on the second integrity protection information, perform an integrity check on the second message.

14. A sending device, characterized in that: It comprises a processor and a memory, wherein a computer program is stored in the memory; the processor is used to read and execute the computer program stored in the memory, so that the method according to any one of claims 1 to 8, or the method according to any one of claims 11 to 12 is executed.

15. A receiving device, characterized in that: It comprises a processor and a memory, wherein a computer program is stored in the memory; the processor is used to read and execute the computer program stored in the memory, so that the method according to any one of claims 9 to 10, or the method according to claim 13, is executed.

16. A computer-readable storage medium, characterized in that: Computer executable instructions are stored, and the computer executable instructions are used to enable a computer to execute the method according to any one of claims 1 to 13.

Images