CN108833440B - Block chain-based network security audit system and network security audit method - Google Patents
Block chain-based network security audit system and network security audit method Download PDFInfo
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- CN108833440B CN108833440B CN201810807355.XA CN201810807355A CN108833440B CN 108833440 B CN108833440 B CN 108833440B CN 201810807355 A CN201810807355 A CN 201810807355A CN 108833440 B CN108833440 B CN 108833440B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L63/00—Network architectures or network communication protocols for network security
- H04L63/04—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks
- H04L63/0428—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload
- H04L63/045—Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload wherein the sending and receiving network entities apply hybrid encryption, i.e. combination of symmetric and asymmetric encryption
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L63/00—Network architectures or network communication protocols for network security
- H04L63/06—Network architectures or network communication protocols for network security for supporting key management in a packet data network
- H04L63/062—Network architectures or network communication protocols for network security for supporting key management in a packet data network for key distribution, e.g. centrally by trusted party
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L63/00—Network architectures or network communication protocols for network security
- H04L63/12—Applying verification of the received information
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
- H04L9/3247—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving digital signatures
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- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
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- Computer Hardware Design (AREA)
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- General Engineering & Computer Science (AREA)
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Abstract
The invention relates to a network security audit system and a network security audit method based on a block chain, wherein an audit server applies for a signature public and private key pair and a key to a key management server, a block chain block generation server applies for a signature public key to the key management server, and the audit server collects data to be audited and encrypts the data to generate the dataC 1 Re-encrypting the encryption key to generateC 2 By a private key pairC 1 AndC 2 digital signature generationσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσand after the block generation server is verified to be effective by the public key, the to-be-audited counting data is placed into a data buffer area, if the block generation condition is met, a new block is generated and broadcasted, and the display end can request the block generation server to check the audit data. According to the invention, a block chain technology is applied, the block chain is added in the audit system, the audit data cannot be tampered, the data security is improved, the audit data in the block chain is encrypted to ensure that the audit data is only accessed by an authorized user, and the confidentiality of the audit data is protected.
Description
Technical Field
The invention relates to the technical field of confidential communication, in particular to a block chain-based network security audit system and a network security audit method, which add a block chain component in a traditional audit system to ensure that audit data cannot be tampered.
Background
The computer network security audit is a process of checking, examining and checking the environment and activities of operation events by using information such as records, system activities, user activities and the like according to a certain security policy so as to discover system bugs and intrusion behaviors or improve system performance, and is also a process of examining and evaluating system security risks and taking corresponding measures. The network security audit carries out independent examination and estimation on system records and behaviors, provides deterrence and warning for potential attackers which may exist, tests the control condition of the system and timely adjusts the control condition to ensure the coordination with the security strategy and the operation regulation, evaluates the occurred damage events, provides effective disaster recovery and basis for pursuing responsibility, evaluates and feeds back changes in system control, the security strategy and the regulation so as to revise decision and deployment, and assists a system administrator to timely find network system intrusion or potential system vulnerabilities and hidden dangers.
However, in the conventional audit system, a system administrator can add and delete audit data, and the obtained audit data and the read audit data have the defect that consistency cannot be ensured, that is, the network security audit has great possibility of losing the significance of the network security audit, and the network security cannot be ensured.
Disclosure of Invention
The invention solves the technical problem that in the prior art, a system administrator can add and delete audit data, and the obtained audit data and the read audit data have the defect that the consistency cannot be ensured.
The technical scheme adopted by the invention is that a network security audit method based on a block chain comprises the following steps:
step 1: data initialization, any audit server applies for signature public and private key pair from key management server（pka, ska）And a secret keypkbThe block chain block generation server applies the signature public key to the key management serverpka；
Step 2: the audit server collects original audit datamAnd using the encryption keykEncrypt, generateC 1 By usingpkbTo pairkEncrypt, generateC 2 By usingskaTo pairC 1 AndC 2 performs digital signature to generateσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσ；
and step 3: block generation server utilizationpkaAuthenticationC 1 、C 2 Andσif not, discardingC 1 、C 2 Andσgo to step 5, otherwise, willC 1 、C 2 Andσputting the data into a data buffer area, judging whether the block generation condition is met, if so, carrying out the next step, and otherwise, returning to the step 2;
and 4, step 4: the block generation server generates and broadcasts a new block, the new block including the original audit datam；
And 5: the display end requests the block generation server to check the audit data, when the number of the unedited blocks in the block generation server is larger than 0, if decryption is passed, the display end obtains the original audit datamOtherwise, carrying out the next step;
step 6: and (6) ending.
Preferably, in step 1, the signed public and private key pair of any audit server（pka,ska）And a secret keypkbIs unique.
Preferably, in step 1, the display terminal applies for a decryption private key from the key management serverskb。
Preferably, in step 5, the display end requests the block generation server to view audit data, and obtains the audit data when the number of non-audited blocks in the block generation server is greater than 0C 1 AndC 2 to do so byskbTo pairC 2 Decrypting to obtain an encryption keykTo do so bykTo pairC 1 Decrypting to obtain the original audit datam。
Preferably, the encryption keykIs a symmetric key.
A network security audit system adopting the block chain-based network security audit method comprises an audit server for collecting audit data and a display end for displaying the audit data, and the network security audit system further comprises:
the block generation server is used for verifying the validity of the audit data acquired by the audit server and packing and adding the audit data into a block chain in due time;
a key management server for managing and distributing keys and signature public and private key pairs required by the audit server, the block generation server and the display end;
the audit server is respectively matched with the key management server and the block generation server; the display end is respectively matched with the key management server and the block generation server; the block generation server is also matched with the key management server.
Preferably, the network security audit system comprises 1 or more block generation servers.
Preferably, when the network security audit system comprises a plurality of block generation servers, a common mechanism is provided among the plurality of block generation servers, and the common mechanism cooperates with any one block generation server.
Preferably, the block generation server is a computer cluster.
The invention provides an optimized network security auditing system and method based on a block chain, wherein an auditing server applies for a signature public and private key pair and a key to a key management server, a block chain block generation server applies for a signature public key to the key management server, the auditing server collects original auditing data and encrypts by using an encryption key to generateC 1 Re-encrypting the encryption key with the key to generateC 2 Using private key pairsC 1 AndC 2 performs digital signature to generateσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσand the block generation server verifies the validity by using the public key, and if the validity is verified, the block generation server verifies the validity by using the public keyC 1 、C 2 Andσand (3) putting the data into a data buffer area, generating a new block when the block generation condition is met, broadcasting, and when the number of the unedited blocks in the block generation server is more than 0, requesting the block generation server to check the audit data by the display end. The invention uses the block chain technology, adds the block chain component in the traditional auditing system, thereby ensuring that the auditing data can not be falsified, greatly improving the safety of the data, ensuring that the block chain can normally work as a distributed account book mode by encrypting the auditing data in the block chain, and ensuring that the auditing data only can work normallyAnd the authorized user accesses the audit data, so that the confidentiality of the audit data is protected.
Detailed Description
The present invention is described in further detail with reference to the following examples, but the scope of the present invention is not limited thereto.
The invention relates to a network security auditing method based on a block chain, which adds a block chain component in a traditional auditing system so as to ensure that auditing data cannot be tampered.
The method comprises the following steps.
Step 1: data initialization, any audit server applies for signature public and private key pair from key management server（pka, ska）And a secret keypkbThe block chain block generation server applies the signature public key to the key management serverpka。
In the step 1, the signature public and private key pair of any audit server（pka,ska）And a secret keypkbIs unique.
In the step 1, the display terminal applies for a decryption private key from the key management serverskb。
In the invention, the public key is a public part in a public and private key pair, the private key is a non-public part, the public key and the private key are the key pair obtained through an algorithm, and generally, data is encrypted by the public key, decrypted by the private key, signed by the private key and verified by the public key.
The present invention relates to a distributed ledger, which is a database shared, replicated, and synchronized among network members for recording transactions, such as the exchange of assets or data, among network participants.
Step 2: the audit server collects original audit datamAnd using the encryption keykEncrypt, generateC 1 By usingpkbTo pairkEncrypt, generateC 2 By usingskaTo pairC 1 AndC 2 performs digital signature to generateσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσ。
in the invention, the block generation server is a block generation server of a block chain.
In the present invention, a key is encryptedkIs generated randomly according to the requirement.
And step 3: block generation server utilizationpkaAuthenticationC 1 、C 2 Andσif not, discardingC 1 、C 2 Andσgo to step 5, otherwise, willC 1 、C 2 Andσand (5) placing the data into a data buffer area, judging whether the block generation condition is met, if so, carrying out the next step, and otherwise, returning to the step (2).
In the present invention,pkaauthenticationC 1 、C 2 Andσis mainly used for verifying the validity of the signature.
In the present invention, the block generation condition is dynamic, and the current situation can be controlled by those skilled in the art.
And 4, step 4: and 4, step 4: the block generation server generates and broadcasts a new block, the new block including the original audit datam。
And 5: the display end requests the block generation server to check the audit data, when the number of the unedited blocks in the block generation server is larger than 0, if decryption is passed, the display end obtains the original audit datamOtherwise, the next step is performed.
In the step 5, the display terminal requests the block generation server to check the audit data, and when the number of the unedited blocks in the block generation server is greater than 0, the audit data is obtainedC 1 AndC 2 to do so byskbTo pairC 2 Decrypting to obtain an encryption keykTo do so bykTo pairC 1 Decrypting to obtain the original audit datam。
Step 6: and (6) ending.
In the invention, the block chain technology is utilized to audit datamEncrypt and pairThe encryption key is re-encrypted, and the data is required to be decrypted successively when finally obtained, thereby ensuring the audit datamConfidentiality and security.
The encryption keykIs a symmetric key.
The invention also relates to a network security audit system adopting the block chain-based network security audit method, which comprises an audit server for collecting audit data and a display end for displaying the audit data, and the network security audit system also comprises:
the block generation server is used for verifying the validity of the audit data acquired by the audit server and packing and adding the audit data into a block chain in due time;
a key management server for managing and distributing keys and signature public and private key pairs required by the audit server, the block generation server and the display end;
the audit server is respectively matched with the key management server and the block generation server; the display end is respectively matched with the key management server and the block generation server; the block generation server is also matched with the key management server.
In the invention, the audit server sends the data to the block generation server after encrypting and signing.
In the invention, the display end extracts data from the block of the block generation server, decrypts the data to finally obtain and display original audit data.
The network security audit system comprises 1 or more block generation servers.
When the network security audit system comprises a plurality of block generation servers, a common identification mechanism is arranged among the block generation servers, and the common identification mechanism is matched with any one block generation server.
In the invention, the consensus mechanism is a mechanism that the block chain nodes achieve the overall network consensus on the block information, which can ensure that the latest block is accurately added to the block chain, the block chain information stored by the nodes is consistent and not forked, and even can resist malicious attack.
The block generation server is a computer cluster.
The invention applies for the public and private key pair and the key of the signature to the key management server through the audit server, the block chain block generation server applies for the public key of the signature to the key management server, the audit server collects the original audit data and encrypts the data by using the encryption key to generate the public key of the signatureC 1 Re-encrypting the encryption key with the key to generateC 2 Using private key pairsC 1 AndC 2 performs digital signature to generateσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσand the block generation server verifies the validity by using the public key, and if the validity is verified, the block generation server verifies the validity by using the public keyC 1 、C 2 Andσand (3) putting the data into a data buffer area, generating a new block when the block generation condition is met, broadcasting, and when the number of the unedited blocks in the block generation server is more than 0, requesting the block generation server to check the audit data by the display end. According to the invention, a block chain technology is applied, and a block chain component is added in a traditional audit system, so that the non-tampering of audit data is ensured, the security of the data is greatly improved, the normal work of the block chain as a distributed account book mode is ensured by encrypting the audit data in the block chain, the audit data is only accessed by an authorized user, and the confidentiality of the audit data is protected.
Claims (9)
1. A network security audit method based on a block chain is characterized in that: the method comprises the following steps:
step 1: data initialization, any audit server applies for signature public and private key pair from key management server（pka,ska）And a secret keypkbThe block chain block generation server applies the signature public key to the key management serverpka；
Step 2: the audit server collects original audit datamAnd using the encryption keykEncrypt, generateC 1 By usingpkbTo pairkEncrypt, generateC 2 By usingskaTo pairC 1 AndC 2 performs digital signature to generateσ(ii) a The audit server sends to the block generation serverC 1 、C 2 Andσ；
and step 3: block generation server utilizationpkaAuthenticationC 1 、C 2 Andσif not, discardingC 1 、C 2 Andσgo to step 5, otherwise, willC 1 、C 2 Andσputting the data into a data buffer area, judging whether the block generation condition is met, if so, carrying out the next step, and otherwise, returning to the step 2;
and 4, step 4: the block generation server generates and broadcasts a new block, the new block including the original audit datam(ii) a The number of the block generating servers is 1 or more, when the network security audit system comprises a plurality of block generating servers, a common identification mechanism is arranged among the block generating servers, and the common identification mechanism is matched with any one block generating server;
and 5: the display end requests the block generation server to check the audit data, when the number of the unedited blocks in the block generation server is larger than 0, if decryption is passed, the display end obtains the original audit datamOtherwise, carrying out the next step;
step 6: and (6) ending.
2. The block chain-based network security audit method of claim 1 wherein: in the step 1, the signature public and private key pair of any audit server（pka,ska）And a secret keypkbIs unique.
3. The block chain-based network security audit method of claim 1 wherein: in the step 1, the display terminal applies for a decryption private key from the key management serverskb。
4. The method of claim 3A block chain-based network security audit method is characterized in that: in the step 5, the display terminal requests the block generation server to check the audit data, and when the number of the unedited blocks in the block generation server is greater than 0, the audit data is obtainedC 1 AndC 2 to do so byskbTo pairC 2 Decrypting to obtain an encryption keykTo do so bykTo pairC 1 Decrypting to obtain the original audit datam。
5. The block chain-based network security audit method of claim 1 wherein: the encryption keykIs a symmetric key.
6. A network security auditing system adopting the block chain-based network security auditing method of any one of claims 1 to 5, comprising an auditing server for collecting auditing data and a display end for displaying the auditing data, characterized in that: the network security audit system further comprises:
the block generation server is used for verifying the validity of the audit data acquired by the audit server and packing and adding the audit data into a block chain in due time;
a key management server for managing and distributing keys and signature public and private key pairs required by the audit server, the block generation server and the display end;
the audit server is respectively matched with the key management server and the block generation server; the display end is respectively matched with the key management server and the block generation server; the block generation server is also matched with the key management server.
7. The network security audit system of the block chain based network security audit method according to claim 6, wherein: the network security audit system comprises 1 or more block generation servers.
8. The network security audit system of a block chain based network security audit method according to claim 7, wherein: when the network security audit system comprises a plurality of block generation servers, a common identification mechanism is arranged among the block generation servers, and the common identification mechanism is matched with any one block generation server.
9. The network security audit system of the block chain based network security audit method according to claim 6, wherein: the block generation server is a computer cluster.
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109474599A (en) * | 2018-11-19 | 2019-03-15 | 杭州安恒信息技术股份有限公司 | Network protection method and device based on block chain |
| CN109729068B (en) * | 2018-11-23 | 2021-05-07 | 北京丁牛科技有限公司 | Security vulnerability auditing system based on block chain technology |
| CN109784920B (en) * | 2018-12-27 | 2023-07-18 | 上海边界智能科技有限公司 | Transaction information auditing method and device based on blockchain |
| CN110147995A (en) * | 2019-05-06 | 2019-08-20 | 山东公链信息科技有限公司 | A kind of auditing method based on key level |
| CN111143837A (en) * | 2019-12-25 | 2020-05-12 | 天津南大通用数据技术股份有限公司 | Method for storing database security audit record |
| CN113139194A (en) * | 2020-01-20 | 2021-07-20 | 华控清交信息科技(北京)有限公司 | Public security data query method, device, terminal equipment and medium |
| CN113411191B (en) * | 2021-08-20 | 2021-11-23 | 深圳前海微众银行股份有限公司 | Data auditing method and device |
| CN114900373B (en) * | 2022-07-11 | 2022-10-14 | 南京极域信息科技有限公司 | Dynamic encryption system and method for realizing audit data storage |
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