CN1558593A

CN1558593A - Method for preventing network game external suspension by employing cryptography

Info

Publication number: CN1558593A
Application number: CNA200410001138XA
Authority: CN
Inventors: 阳胡; 胡阳
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-01-30
Filing date: 2004-01-30
Publication date: 2004-12-29

Abstract

The invention discloses a method for externally suspension of network games by adopting cryptography, wherein the two ends of the client machine and the network game server are provided with a common cipher machines, the symmetrical cryptographic algorism is employed as the encryption algorithm for encryption for the data packet transmitted between the network game server end and client machine end, the network game server end and client machine end conduct encryption to the data packets with the same encryption algorithm to create encryption data packet.

Description

Adopt cryptographic technique to prevent the method for network game external store

Technical field:

The present invention relates to filed of network information security, is to realize the data of network game bag is carried out encryption and decryption with cryptographic technique, prevents network game external store, and this technology is applicable to each online game operator.

Background technology:

At present, the safe practice of online game almost is blank at home, the method that wherein solves network game external store is in passive state all the time, basically be plug-in user in the player, to occur, after operator's affirmation is errorless, to its number of deleting punishment, though this method can play some punishment effects, but can not fundamentally solve the plug-in problem of online game, this has greatly influenced the sound development of online game.

Summary of the invention:

Adopt cryptographic technique to prevent the method for network game external store, be to adopt computer, password and network technology to come building network game data packet encryption system, at network game server end and client-side a pair of identical cipher machine is set respectively, its cryptographic algorithm is a symmetry algorithm, encrypt by packet, realize the safe transmission of packet, prevent that packet is modified or replaces online game, all processes realizes that with hardware or hardware, software combination concrete grammar is as follows:

1, each client-side has cover mutually different " sub-key " group N, every cover " sub-key " group N has a user number corresponding with it, N=600～1740 group, the length of every group " sub-key " is 8 bits～32 bits, itself and one group of user number are left in the digital key, this numeral key is realized with hardware, is a built-in CPU intelligent chip, has the USB hardware device of intelligent card function.

2, the cryptographic algorithm of client-side cipher machine realizes with software, leave in the client-side hard disk, and regularly from the network game server end down loading updating; The cryptographic algorithm of network game server end cipher machine realizes with hardware or software, if software then leaves in the hard disk of network game server.

3, network game server end has All Clients end " sub-key " group, it is encrypted with one group of fixed key F, close " sub-key " group user number corresponding with it after encrypting left on the hard disk of network game server end, and this fixed key F leaves in the digital key.

4, user number is made up of English alphabet or numeral, and length is 4～16, corresponding cover " sub-key " group of each user number; Timestamp is to produce according to the network game server end system for computer time, is made up of 8 bit digital; Random code is produced at random by network game server or client computer, and its length is K, K=10～16, and variable quantity is 10 ¹⁰～10 ¹⁶, by user number, timestamp and random code control " sub-key " group of user to be carried out at random, made up in real time and choose, the method that this key is chosen can reach one-time pad, does not reuse, and also toos many or too much for use in 10 years.

5; the key generative process of network game server end is; elder generation's generation time stabs and random code; and according to timestamp and random code from cover close " sub-key " group of user number correspondence; select K group close " sub-key " and synthetic one group of decryption key; use one group of fixed key F in the network game server end numeral key again; its deciphering is reduced into key; at last; this key is put in the cipher machine; encrypt generation ciphertext data bag M1 to being about to client-side data packets for transmission T; this ciphertext data bag M1 is the same with packet T size; but content difference; with user number; timestamp; random code and ciphertext data bag are issued client-side together as parameter from network game server end, are used for the protection to data of network game bag safety.

6, after client-side receives this parameter, from cover " sub-key " group of client-side, select K group " sub-key " according to the user number in the parameter, timestamp and random code, and a synthetic group key, again the ciphertext data bag is decrypted.

7, when the recreation of player's operational network, and will be when network game server end sends packet, in the process that this packet generates it is encrypted, promptly the every generation part of packet is just encrypted this part, is encrypted to the ciphertext data bag until whole packet; Or packet is encrypted to the ciphertext data bag as long as generating a bit just encrypts this bit up to whole packet, makes encryption system and data of network game bag reach seamless combination; Its encryption key is the random code that the timestamp that transmits according to network game server end and client-side produce, in cover " sub-key " group of client-side, select a K group " sub-key " and a synthetic group key, user number, timestamp, random code and ciphertext data bag are sent to network game server end in the lump, and network game server end is decrypted this ciphertext data bag again.

8, the random code of client-side and network game server end generation is thousand changes, ten thousand flowers, the random code that network game server end sent client-side the same day, all register at network game server end at every turn, under same user number, same timestamp, the situation that random code is identical is very little especially, when if network game server end receives the parameter appearance mistake of client-side transmission, that is: timestamp is not right, or the reusable words of random code, network game server end can be considered as it illegal parameter, and prompting client-side packet is wrong.

Description of drawings:

Fig. 1: the flow chart that is transferred to network game server end after client-side is encrypted packet

Fig. 2: the flow chart that is transferred to client-side after network game server end is encrypted packet

Embodiment:

Performing step below in conjunction with description of drawings packet encipher-decipher method:

Fig. 1: the random code that timestamp that transmits according to network game server end and client computer self produce, from cover " sub-key " group of client-side, select K group " sub-key " and synthetic key, with this key client-side being sent out the packet of giving network game server end encrypts, its encryption is to carry out in the process that packet forms, be that the data bound edge forms the limit encryption, reach packet and encryption system seamless combination, with user number, timestamp, parameters such as random code and ciphertext data bag transfer to network game server end in the lump, if the timestamp that network game server end detects in the parameter is not right, or random code is reused, then will be considered as illegal parameter to this parameter, and return data is surrounded by mistake, after if review time stamp and random code are errorless, then from cover " sub-key " group of this user number correspondence, select K group close " sub-key " and synthetic one group of decryption key, with fixed key F it is deciphered again, generate key, at last, with this key the ciphertext data bag is decrypted.

Fig. 2: the network game server end rise time stabs and random code, according to user number, timestamp and random code are from cover close " sub-key " group of this user number correspondence, select K group close " sub-key " and synthetic decryption key, with a fixing group key F this group decryption key is decrypted the generation key again, with this key packet is encrypted generation ciphertext data bag, with user number, timestamp, random code and ciphertext data bag transfer to client computer together, client computer is according to the timestamp and the random code that transmit, from cover " sub-key " group of client-side, select K group " sub-key ", an and synthetic group key, again the ciphertext data bag is decrypted, generates packet.

Claims

1, adopt cryptographic technique to prevent the method for network game external store, be an identical cipher machine to be set respectively in network game server end and client, its cryptographic algorithm is a symmetry algorithm, data packets for transmission between network game server end and the client is encrypted, its key adopts the combination generating mode, reach one-time pad, network game server end is encrypted packet with identical key and cryptographic algorithm with client and is generated the ciphertext data bag, with this ciphertext data bag, user number, timestamp and random code are transmitted at network game server and client computer two ends mutually through network in the lump, receiving terminal is decrypted according to the various parameters that transmit, be reduced into bright packet, thereby solve the problem of network game external store.

2, require the described method that prevents network game external store according to right 1, it is characterized in that:

Utilize symmetric cryptographic algorithm that the data of network game bag is carried out encryption and decryption, promptly utilize block cipher, or the data of network game bag is carried out encryption and decryption with stream cipher algorithm.

3, require the described method that prevents network game external store according to right 1, it is characterized in that:

Carry out in the encryption and decryption at the packet to online game, each user uses a mutually different cover key, and reaches one-time pad.

4, require the described method that prevents network game external store according to right 1, it is characterized in that:

The packet that client passes to network game server end is to encrypt in the process that is generating, and promptly the every generation part of packet is just encrypted this part, is encrypted to the ciphertext data bag until whole packet; Or packet is encrypted to the ciphertext data bag as long as generating a bit just encrypts this bit up to whole packet, thereby, reach data of network game bag and encryption system seamless combination, replaced or revised to prevent the data of network game bag.

5, require the described method that prevents network game external store according to right 1, it is characterized in that:

Cryptographic algorithm to network game server end and client cipher machine is carried out regular update, and client is downloaded the cipher machine cryptographic algorithm of having upgraded from network game server end at every turn, decodes ability with the anti-group of improving encryption system.