CN101257517B - Method and device for processing address analysis protocol request message - Google Patents

Abstract

The invention discloses an address resolution protocol request message processing method, comprising: after receiving an address resolution protocol request packet from a sender, constructing an address resolution protocol response packet according to the information in the address resolution protocol request packet, and analyzing the address The physical address of the source end of the protocol response packet is set to a predetermined value; and the constructed address resolution protocol response packet is sent to the sender. In addition, the invention also discloses an address resolution protocol request message processing device. According to the technical solution of the present invention, the stability of the IP CS network and the normal transmission of data can be guaranteed; and, it can be applied to various forms of user equipment under the WiMAX network and with various operating systems (for example, linux operating system, windows operating system) or devices without an operating system, which have good versatility.

Description

Address resolution protocol request message processing method and device

technical field

The present invention relates to the field of wireless communication, and in particular, relates to a method and device for processing an address resolution protocol request message. the

Background technique

Like most protocols, the Medium Access Control (MAC) specification of IEEE 802.16 adopts a layered structure, and the protocol is divided into three sublayers: Service Specific Convergence Sublayer, Public Part Sublayer Layer (Common Part Sublayer), and Security Sublayer (Security Sublayer). The main function of the convergence sublayer is to be responsible for converting and mapping the external data received by its access point (SAP) to the MAC service data unit (SDU), and passing it to the MAC layer service access point (SAP), that is, connecting The public part of the service (MAC service) is mapped to a standard type of service. the

In addition, the MAC protocol defines two CS types, Asynchronous Transfer Mode (ATM) CS and Pocket CS, among which Pocket CS provides support for 802.3 (Ethernet, Ethernet), 802.1Q (Virtual Local Area Network, VLAN), and IP ( IPv4, IPv6) and other packet service mapping. the

IP CS exchanges IP packets between two network endpoints. Only IP packets on the air interface are sent to the Worldwide Interoperability for Microwave Access (WiMAX) base station (Base Station, BS), and other protocol packets are discarded. For example, Internet work Packet Exchange (IPX), sequence packet exchange (Sequences Pocket Exchange, SPX) packets. FIG. 1 is a schematic diagram of the message format of the above-mentioned IP format data packet. the

In general, WiMAX user equipment will use an operating system with a network protocol stack for network-related processing. WiMAX user equipment registers with the operating system as a network interface, and sends and receives data packets through the network protocol stack of the operating system. . Figure 2 is a schematic diagram of the network protocol stack and 802.16 system in the operating system, as shown in Figure 2, in the current operating system (for example, linux, windows), the 802.16 network subsystem is considered as a common 802.3 Ethernet device , and communicate with this 802.16 subsystem in the form of 802.3 interface. Figure 3 is the sending and receiving packet format of the 802.3 Ethernet interface. In actual operation, after the network protocol stack of the operating system encapsulates the data packet into an Ethernet packet as shown in Figure 3, it is handed over to the MAC layer of the 802.16 subsystem for processing. the

It can also be seen from FIG. 3 that, in addition to the IP datagram type (0800), the data part in the Ethernet packet also includes an address resolution protocol (ARP) request type (0806). ARP can be used to realize the dynamic conversion from IP address to MAC address. By using ARP, the MAC address of a certain IP address can be obtained. The ARP packet format is shown in Figure 4; by sending a broadcast message with this packet format to the network, you can Obtain the MAC address corresponding to the destination IP address. the

But in the 802.16 system, the MAC layer is connection-oriented, and each connection is uniquely identified by an identifier CID (Connect ID). Therefore, in the process of data transmission, the MAC address does not need to be used, so there is no need to Ethernet's ARP protocol is required. This is why the IPv4 CS in the 802.16 system does not process ARP packets. the

Therefore, in this 802.16 system application scenario, if the ARP request is not processed or discarded, the ARP request sent from the network protocol stack of the operating system cannot be responded to, resulting in the failure of the sending process, which may lead to communication interruption. Make WiMAX user equipment unable to perform normal voice or data communication, that is to say, currently there is a problem that normal telephone calls or Internet operations may not be performed due to the inability of the IPv4 CS sublayer to correctly process ARP requests. However, a technical solution that can solve this problem has not been proposed so far

Contents of the invention

The present invention is made in consideration of the above problems. Therefore, the main purpose of the present invention is to provide an address resolution protocol request message processing method and device. In order to solve the problem in the related art that the IPv4CS sublayer in the 802.16 system cannot correctly process the ARP request. the

According to an embodiment of the present invention, an address resolution protocol request message processing method is provided, which is used for processing the address resolution protocol request message when the 802.16 system adopts IPv4. the

The method includes: after receiving the address resolution protocol request packet from the sender, constructing the address resolution protocol response packet according to the information in the address resolution protocol request packet, and setting the source end physical address of the address resolution protocol response packet as a predetermined value , where the predetermined value satisfies the following conditions: there is no conflict with other MAC addresses in the system; and the constructed ARP response packet is sent to the sender. the

Wherein, the ARP response packet is constructed according to at least one of the following information in the ARP request packet: source address, source address type, user equipment address, hardware type, protocol type, protocol address, source protocol address. the

Preferably, the address of the user equipment can be modified, and the modified address of the user equipment can be used as the source end physical address of the address resolution protocol response packet. the

Preferably, the manner of modifying the address of the user equipment may be to add 1 to the address of the user equipment. the

According to another embodiment of the present invention, an address resolution protocol request message processing device is also provided, which is used for processing the address resolution protocol request message when the 802.16 system adopts IPv4. the

The device includes: a receiving module, configured to receive an address resolution protocol request packet from a sender; a construction module, configured to construct an address resolution protocol response packet according to information in the address resolution protocol request packet, and send the source of the address resolution protocol response packet The terminal physical address is set to a predetermined value, wherein the predetermined value meets the following conditions: there is no conflict with other MAC addresses in the system; the sending module is used to send the constructed ARP response packet to the sender. the

Wherein, the construction module constructs the address resolution protocol response packet according to at least one of the following information in the address resolution protocol request packet: source address, source address type, user equipment address, hardware type, protocol type, protocol address, source protocol address . the

Preferably, the construction module can modify the user equipment address, and use the modified user equipment address as the source end physical address of the address resolution protocol response packet. the

Preferably, the configuration module modifies the address of the user equipment by adding 1 to the address of the user equipment. the

Through the above technical scheme of the present invention, the stability of the IP CS network and the normal transmission of data can be guaranteed; and, it can be applied to various forms of user equipment under the WiMAX network and with various operating systems (for example, linux operating system) system, windows operating system) or devices without an operating system, which have good versatility. the

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention and constitute a part of the application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention. In the attached picture:

Fig. 1 is the schematic diagram according to the message format of the IP format packet of related art;

Fig. 2 is a schematic diagram of the interaction between the network protocol stack and the 802.16 system in the operating system according to the related technology;

Fig. 3 is the schematic diagram according to the format of sending and receiving packets of the 802.3 Ethernet interface of related art;

Fig. 4 is a schematic diagram of the ARP packet format according to related technologies;

Fig. 5 is the flow chart of the address resolution protocol request message processing method according to the method embodiment of the present invention;

Fig. 6 is the flow chart of the detailed processing procedure of the address resolution protocol request message processing method according to the method embodiment of the present invention;

Fig. 7 is the signaling flowchart of the WiMAX mobile station power-on access network according to the method embodiment of the present invention; And

Fig. 8 is a block diagram of an apparatus for processing an address resolution protocol request message according to an embodiment of the apparatus of the present invention. the

Detailed ways

Method Example

In this embodiment, an address resolution protocol request message processing method is provided, which is used for processing the address resolution protocol request message when the 802.16 system adopts IPv4. the

Fig. 5 is a flowchart of a method for processing an address resolution protocol request message according to an embodiment of the present invention. the

As shown in FIG. 5, the method for processing an address resolution protocol request message according to an embodiment of the present invention includes: step S502, after receiving the address resolution protocol request packet from the sender, constructing the address resolution protocol according to the information in the address resolution protocol request packet A protocol response packet, and set the source physical address of the ARP response packet as a predetermined value; Step S504, sending the constructed ARP response packet to the sender. the

Wherein, the ARP response packet is constructed according to at least one of the following information in the ARP request packet: source address, source address type, user equipment address, hardware type, protocol type, protocol address, source protocol address. the

Preferably, the user equipment address is modified, and the modified user equipment address is used as the source end physical address of the address resolution protocol response packet. the

That is to say, for the ARP request entering the 802.16 subsystem, a so-called ARP spoofing mechanism can be adopted to ensure that the sending end gets a correct response. After the data is sent to the 802.16 system, the IPv4 CS sublayer of 802.16 first needs to monitor the received packet format, if it is found that the packet to be sent is an ARP request packet, it will be intercepted and filled with an arbitrary MAC address ( For example, the MAC address of the WiMAX user equipment + 1) is directly returned to the network protocol stack at the sending end as an ARP response, and does not continue to send to the next step of the 802.16 system. In this way, it can be ensured that the ARP request sent by the network protocol stack will be responded in time, and normal data transmission will not be affected. Thereby improving the stability of the system. the

In order to perform this process, we need to construct an ARP response packet in Ethernet format, that is, as shown in Figure 3, we must first set the Ethernet header, including destination address, source address and type, where the destination address and type can be obtained from ARP Obtained from the request packet, the source address is filled with the address of the WiMAX user equipment. The next step is to fill in the ARP field (as shown in Figure 4), most of which can be obtained from the ARP request packet, including hardware type, protocol type, destination physical address, protocol address, and source protocol address. the

Preferably, considering factors such as processing speed, the method of modifying the user equipment address is to add 1 to the user equipment address (WiMAX user equipment MAC address+1). Those skilled in the art should understand that adding 1 to the address is just an example, and it can also be modified in other ways in practical applications, for example, adding other values to or subtracting a certain value from the MAC address of the user equipment. In a word, the MAC address of the user equipment as the predetermined value above should satisfy the following condition: no conflict with other MAC addresses in the system. the

That is to say, attention should be paid to the value of the physical address of the source end, and an appropriate value (the aforementioned predetermined value) should be selected. The main basis for selecting this value is not to conflict with other MAC addresses in the system. Generally, we select the MAC address of the WiMAX user equipment plus 1. the

After the required fields of the ARP response are filled, the receiving function can be called, and the 802.16 IPV4 CS sublayer sends the ARP response packet back to the network protocol stack (Step504-508). the

According to this method, the network protocol stack of the operating system in the WiMAX user equipment can obtain a timely and correct ARP response packet, and update its own ARP list according to the content. the

Fig. 6 is a flow chart of a preferred embodiment of the method embodiments according to the present invention. Next, the processing of the above technical solution will be described with reference to FIG. 6 . As shown in Figure 6, it specifically includes the following processing procedures:

Steps 601-603, the IPv4 CS sublayer of the 802.16 system detects the received packet, and judges whether it is an ARP request packet;

There are two cases here, the first case is obtained from the type field definition shown in Figure 2; the second case, if the IPv4 circuit domain (CS) sublayer detects that the packet sent is not an ARP request packet, then Carry out next normal 802.16 processing (step 610) to this IP packet data;

Steps 604-608, if the IPv4 CS sublayer detects that the packet type is indeed an ARP packet, then construct an ARP response packet according to the received packet, wherein the destination physical address can be arbitrarily selected, and use the operating system protocol after adding the Ethernet header The receiving function of the stack sends it back to the network protocol stack through the 802.3 interface. the

The above technical solution will be described in detail below by taking the process of powering on and starting up the WiMAX mobile station MS to initialize and search for a network as an example. the

Regarding this process, it should be noted that FIG. 7 is only a schematic diagram of the MS being powered on and accessing the network, and does not represent the complete access process of the MS. For the purpose of clarity, only simplified processing procedures are shown here, and those skilled in the art should understand that in actual applications, the commands and procedures for interaction between the MS and the BS are more complex than those shown in FIG. 7 . the

As shown in Figure 7, it specifically includes the following steps:

Steps 710-730, after performing physical layer synchronization, MAC layer synchronization and network access, after the MS sends a DHCP request IP address to the Dynamic Host Configuration Protocol (DHCP) server on the BS side and successfully obtains it, in order to verify whether the connection is successful, the MS Sent a ping command (step 750) to BS, when executing this ping command, MS at first inquires whether there is the MAC address corresponding to this IP in the ARP list of itself, if not, will send an ARP request, according to the preceding Description, the IP CS of the 802.16 system will not process this ARP request, in this case, it is necessary to spoof the ARP request. the

In this process, the ping command will not cause an error because the correct destination MAC address is not obtained. As mentioned earlier, the 802.16 system is a connection-oriented system. Its correct connection does not depend on the MAC address, but establishes a relationship with the connection through the connection identifier (Connect ID, CID), and obtains the destination address and quality of service (Quality of Service) from the CID. of Serives, QoS) requirements. The CID of the MS is obtained from the RNG-RSP message of the ranging procedure in FIG. 7 (step 730). the

The above application example is just a specific application of ARP spoofing. In actual network operations, there are still many application instruction operations that need to send ARP requests. For these operations, ARP spoofing methods are also required to ensure normal communication. . the

For the 802.16 system, it should also be noted that such ARP spoofing will not affect the normal sending of IP data packets. It is known from the previous description that when the IP data packet to be sent enters the 802.16 system from the network protocol stack of the operating system, fields such as the destination address, source address, and type need to be added to the header to be encapsulated into an Ethernet packet, and When the 802.16 system finally transmits the data to the air, for the 802.16 IP CS, the format of the payload needs to be restored to the IP packet format, and the Ethernet header is no longer included. Fields such as the destination address and source address are not used when actually transmitting data. Therefore, even if the destination address here is an incorrect address obtained through ARP spoofing, it will not affect the normal transmission of data. the

In the above description, the operating system involved is linux operating system as an example. In fact, in 802.16 systems with other operating systems (for example, windows), the processing of ARP request instructions is also the same , but because the interface implementation methods of the network layer protocols of each operating system are different, the interface functions called during actual operation are different, but the principle and operation process are exactly the same. the

Device embodiment

In the embodiment, an address resolution protocol request message processing device is provided, which is used for processing the address resolution protocol request message when the 802.16 system adopts IPv4. Fig. 8 is a block diagram of an apparatus for processing an address resolution protocol request message according to this embodiment. the

As shown in Figure 8, the device includes: a receiving module 802, configured to receive an address resolution protocol request packet from the sender; a construction module 804, configured to construct an address resolution protocol response packet according to information in the address resolution protocol request packet, and Set the physical address of the source end of the ARP response packet to a predetermined value; the sending module 806 is configured to send the constructed ARP response packet to the sender. the

Wherein, the construction module 804 constructs the address resolution protocol response packet according to at least one of the following information in the address resolution protocol request packet: source address, source address type, user equipment address, hardware type, protocol type, protocol address, source protocol address. the

Preferably, the construction module 804 can modify the user equipment address, and use the modified user equipment address as the source end physical address of the address resolution protocol response packet. the

Preferably, the configuration module 804 may modify the address of the user equipment by adding 1 to the address of the user equipment. the

Preferably, the predetermined value satisfies the following condition: there is no conflict with other MAC addresses in the system. the

In summary, by means of the technical solution of the present invention, the stability of the IP CS network and the normal transmission of data can be guaranteed; and, it can be applied to various forms of user equipment under the WiMAX network and with various operating systems (for example, linux operating system, windows operating system) or equipment without operating system, the present invention has better versatility; In addition, the IP CS part in the 802.16 protocol has also been supplemented and perfected. the

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention. the

Claims (8)

1. arp request message treatment method, the arp request message when being used for that 802.16 systems are adopted IPv4 is handled, and it is characterized in that said method comprises:

Behind the arp request bag that receives from transmit leg; According to the information structuring address resolution protocol respond packet in the said arp request bag; And the source end physical address of said address resolution protocol respond packet is set to predetermined value; Wherein, said predetermined value meets the following conditions: do not exist with other Media Access Control Address in the native system and conflict;

The said address resolution protocol respond packet of structure is sent to said transmit leg.

2. method according to claim 1; It is characterized in that, according to the said address resolution protocol respond packet of one of at least structure in the following information in the said arp request bag: the type of source address, said source address, user device address, type of hardware, protocol type, protocol address, source protocol address.

3. method according to claim 2 is characterized in that, said user device address is made amendment, with the source end physical address of amended user device address as said address resolution protocol respond packet.

4. method according to claim 3 is characterized in that the mode of revising said user device address is for to add 1 with said user device address.

5. arp request message processing apparatus, the arp request message when being used for that 802.16 systems are adopted IPv4 is handled, and it is characterized in that said device comprises:

Receiver module is used to receive the arp request bag from transmit leg;

Constructing module; Be used for information structuring address resolution protocol respond packet according to said arp request bag; And the source end physical address of said address resolution protocol respond packet is set to predetermined value; Wherein, said predetermined value meets the following conditions: do not exist with other Media Access Control Address in the native system and conflict;

Sending module is used for the said address resolution protocol respond packet of structure is sent to said transmit leg.

6. device according to claim 5; It is characterized in that said constructing module is according to the said address resolution protocol respond packet of one of at least structure in the following information in the said arp request bag: the type of source address, said source address, user device address, type of hardware, protocol type, protocol address, source protocol address.

7. device according to claim 6 is characterized in that said constructing module is made amendment to said user device address, with the source end physical address of amended user device address as said address resolution protocol respond packet.

8. device according to claim 7 is characterized in that, said constructing module is revised the mode of said user device address for said user device address is added 1.

Images