Research on blockchain evaluation methods under the classified protection of cybersecurity
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摘要: 等级保护(简称等保)是我国信息安全的基本政策,随着区块链技术在各行业中的应用日趋广泛,有必要同步推进区块链系统的等级保护测评工作,这将有利于推动该技术在我国的持续健康发展。有鉴于此,依据等保第三级的应用和数据安全要求,给出了区块链系统中对等网络、分布式账本、共识机制和智能合约等核心技术的具体测评要求及实施方案,并从等保2.0规定的控制点出发,分别对当前区块链系统运行数据与基于日志流程的安全审计机制进行了归纳与分析。通过上述评估与分析可知区块链系统在软件容错、资源控制和备份与恢复等方面满足等保要求,而在安全审计、身份鉴别、数据完整性等方面则有待进一步改进。Abstract: A blockchain is a cryptographic distributed database and network transaction accounting system. In the current era of major technological changes, blockchain technology, with its cryptographic structure, peer-to-peer (P2P) network, consensus mechanism, smart contract and other mechanisms, is decentralized, tamper-proof, and traceable and has become a hot spot in the development of informatization. Classified protection is one of the basic policies of information security in China. The implementation of the information security level protection system can not only guide various industries in performing security management in accordance with the equivalent security standards, but also ensure that supervision and evaluation institutions follow the laws and regulations, which is of significance to network security. As the application of blockchain technology in various industries is becoming more extensive, it is necessary to simultaneously promote the national classified protection of blockchain security assessment, which contributes to the sustainable and healthy development of blockchains in China. According to the revised assessment methods of grade protection, in addition to the status of universality requirements, evaluation specifications should be formulated for specific technologies and fields (such as cloud computing, mobile Internet, Internet of Things, industrial control, and big data). In view of the particularity of blockchain technology, China has initiated the formulation of blockchain evaluation specifications, but has not applied the level protection standards to the formulation of blockchain evaluation specifications. Therefore, the assessment requirements and enforcement proposals are specified for the blockchain’s core technologies, such as P2P network, distributed ledger, consensus mechanism, and smart contracts, according to the application and data security layer requirements at Level 3. Moreover, the current running data of blockchains and their security audit mechanism based on the log workflow were summarized and analyzed respectively in compliance with the control points specified in classified protection 2.0. Our investigation indicates that blockchains can satisfy the requirements of evaluation items in three aspects, namely, software fault tolerance, resource control, and backup and recovery. However, further improvements are needed for other aspects, including security audit, access control, identification and authentication, and data integrity.
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表 1 定级要素与安全等级的关系
Table 1. Relation between grading elements and safety level
程度
Degree公民、法人、其他组织
Citizens, corporations and other organizations社会秩序、社会公共利益
Social order, public interest国家安全
National security损害
General damage第一级
Level 1第二级
Level 2第三级
Level 3严重损害
Significant damage第二级
Level 2第三级
Level 3第四级
Level 4特别严重损害
Especially significant damage第三级
*Level 3第四级
Level 4第五级
Level 5* Classified protection 1.0 is level 2. 表 2 等级保护1.0与2.0三级应用层控制点对比
Table 2. Comparison of application layer control points in classified protection 1.0 and 2.0 at level 3
版本
Version类别
Category控制点
Control points等级保护1.0
Classified protection 1.0应用安全
Application security身份鉴别、访问控制、安全审计、通信完整性、通信保密性、软件容错、资源控制
Identity authentication, access control, security audit, communication integrity, communication confidentiality, software fault tolerance, resource control数据安全及备份恢复
Data security and backup recovery数据完整性、数据保密性、备份和恢复
Data integrity, data confidentiality, backup and recovery等级保护2.0
Classified protection 2.0应用和数据安全
Application and data security身份鉴别、访问控制、安全审计、软件容错、资源控制、数据完整性、数据保密性、
数据备份和恢复、剩余信息保护、个人信息保护
Identity authentication, access control, security audit, software fault tolerance, resource control, data integrity, data confidentiality, data backup and recovery, residual
information protection, personal information protection表 3 分布式对等网络测评
Table 3. Distributed peer-to-peer network assessment
类别
Categories测评项
Items实施
Implementation预期效果
Expected Effectiveness实际测评结果说明
Description of actual evaluation results达标
Y/N身份鉴别
Identification节点接入控制
Node link control查看连入区块链是否
需要认证
Check if the connection to the Blockchain requires authentication当节点连入系统时,对其进行身份认证,控制节点接入
When nodes are connected, the system authenticates themto restrict node access.节点接入时没有对身份
进行认证
The identity is not authenticated when the node is connected.否
N软件容错
Software fault tolerance自我保护与自适应
Self-protection and self-adaptation网络不稳定时查看信息传输情况
Inspect information transmission when the network is unstable.网络抖动对传输不会造成太大影响,系统运行稳定Network jitter does not have much impact on transmission. Blockchain runs stably. 网络抖动时,区块链
系统运行稳定
Blockchain system runs stably when network jitter occurs.是
Y资源控制
Resource control并发连接限制
Concurrent connection restriction查看节点最大连接数目
View the maximum number of connections on nodes对最大并发连接进行限制,防止系统资源耗尽
Limit maximum concurrent connections to prevent system resource exhaustion节点连接不超过117个输入连接,向其他节点发起
8个输出连接。
Node connections do not exceed 117 input connections and 8 output connections.是
Y连接超时限制
Connection timeout limit查看相关网络配置
View related network configurations自动结束长期无应答的会话防止系统资源占用
Automatically end long-term unanswered sessions to prevent system resource usage.某个节点超过30 min没有新消息,则发送心跳消息,长达90 min没有通信,则结束会话
If there is no communication for more than 30 minutes, a heartbeat message is sent. End the session if there is no communication for 90 minutes.是
Y数据完整性
Data integrity单播通信防篡改
Anti-tampering of unicast查看数据传输是否加密防
篡改安全
Check whether data transmission is encrypted and tamper-proof数据在点对点通信过程中不被篡改
Data is not tampered with in the process of point-to-point communication.不能保障数据在单播通信过程中的完整性
The integrity of data in unicast communication cannot be guaranteed.否
N广播通信防篡改
Multicast communication tamper-proof能否提供通信多播,广播功能,通信过程中数据是否防篡改
Check whether the system can provide communication multicast, broadcast function and tamper-proof data in the process of communication数据在广播通信过程中
不被篡改
Data is not tampered with during broadcast communication.不能保障数据在广播通信过程中的完整性
The Bitcoin system does not guarantee the integrity of data in the broadcast communication process.否
N转发通信防篡改
Forwarding communication tamper-proof转发功能及数据防篡改
Data tampering prevention in forwarding communication数据在某节点通过转发时
不被篡改
Data is not tampered with when forwarded by a node.不能保障数据在转发通信过程中的完整性
The integrity of data in the process of forwarding communication cannot be guaranteed否
N安全审计
Security audit网络状态获取更新
Network status get update查看日志是否记录
节点状态信息
Check whether the log records
node status information.能够为系统的稳定运行提供可信的节点数据
Ability to provide trusted node data for stable operation of the system.存在单个节点的状态更新记录,但更新记录不进行全网交换,无法获取全网状态
There is a status update record for a single node. However, update records are not exchanged in the whole network, the whole network status cannot be obtained.否
N网络节点动态监测
Network node dynamic monitoring是否对在线节点数量
进行统计
Statistics on the number of
online nodes具备对节点动态增加和减少的识别能力
Ability to recognize nodes dynamically increasing and decreasing.区块链系统具备全网节点数量实时统计能力
The Bitcoin system does not have the real-time statistical ability of the number of nodes in the whole network.是
Y表 4 不同区块链参数选择对网络传输影响[43]
Table 4. Impact of parameter selection on network transmission in different blockchains[43]
Parameter Bitcoin Litecoin Dogecoin Ethereum 区块间隔
Block interval10 min
10 min2.5 min
2.5 min1 min
1 min10−20 s
10−20 s公共节点
Public nodes6000 800 600 4000 挖矿池
Mining pools16 12 12 13 陈腐块率/%
Stale block rate0.41 0.273 0.619 6.8 区块大小/KB
Block size534.8 6.11 8 1.5 表 5 共识机制测评
Table 5. Consensus mechanism assessment
类别
Categories测评项
Items实施
Implementation预期效果
Expected effectiveness实际测评结果说明
Description of actual
evaluation results达标
Y/N资源控制
Resource control共识资源控制
Consensus resource control检测计算机中资源
使用情况。
Check the use of resources in the computer共识机制消耗计算机资源
应该最小化原则
Consensus mechanisms should minimize the consumption of computer resources.PoW共识机制计算资源耗费较大,但系统资源可控
PoW consumes a lot of computing resources, but the system resources are controllable.是
Y备份与恢复
Backup and recovery实时备份
Real-time backup查看节点是否同步了
新共识区块
Check whether the node has synchronized the new consensus block全网节点具有相同的数据副本
All network nodes have the
same data replica.节点实时备份区块链中产生的交易数据
Real-time backup of transaction data generated in Bitcoin system by nodes.是
Y系统热冗余
System hot redundancy查看节点瘫痪后
系统可用性
View system availability after node paralysis业务连续性未被中断
Business continuity not interrupted.节点之间互为冗余,单一或少数节点故障不影响系统稳定性和可用性
Nodes are redundant to each other and single or few node failures do not affect the stability and availability of the system.是
Y共识效果
Consensus effect共识容错性
Consensus fault tolerance设置异常节点,查看共识情况
Set exception nodes and view consensus.存在共识阈值,使得超过阈值的节点达到共识即代表全网共识完成
There is a consensus threshold, so that the node exceeding the threshold reaches the consensus, which means that the consensus of the whole network is completed.系统可容纳5%的节点共识错误。95%以上的节点
共识成功即可
The system can accommodate 5% node consensus errors. More than 95% of the nodes are successful.是
Y共识有效性
Consensus Effectiveness发起非法交易,查看共识是否失败
Initiate an illegal transaction to see if the consensus failed非法交易共识失败。通过对交易进行正确性和逻辑性验证,使恶意造假交易的代价昂贵,避免恶意共识
Illegal transaction consensus failed. By verifying the correctness and logic of the transaction, the cost of malicious fraudulent transactions is expensive and avoids malicious consensus.非法交易不能被共识通过
Illegal transactions cannot be passed by consensus.是
Y共识结果一致性
Consensus consistency发起合法交易,查看共识结果是否满足一致
Initiate a legal transaction and see if the consensus result is consistent忠诚参与方共识结果
具有一致性
Loyal participant consensus results are consistent.对于合法交易区块链系统达成共识后写入区块链
After agreeing on the legal transaction of Bitcoin system, it is written into the blockchain.是
Y表 6 分布式账本测评
Table 6. Distributed ledger assessment
类别
Categories测评项
Items实施
Implementation预期效果
Expected effectiveness实际测评结果说明
Description of actual evaluation results达标
Y/N软件容错
Software fault tolerance账本格式规范性
Standardization of ledger查看账本中的数据格式是否有统一标准
Check whether the data format in the ledger has a uniform standard交易、区块等数据按照数据格式进行存储
Data such as transactions and blocks are stored
in data format.区块链系统交易、区块等均有统一组织标准
Blockchain system transactions, blocks, etc. have unified organizational standards.是
Y访问控制
Access control账本访问控制
Ledger access control查看是否存在访问策略监管节点及访问控制策略
Check whether there is an access policy supervision node and access control policy对账本上的数据资源进行保护,防止非法访问
Protect the data resources
on the ledger against
illegal access作为公有链系统没有完备的访问控制策略
Bitcoin as a public blockchain, there is no complete access control strategy否
N数据完整性
Data integrity存储完整性
Storage integrity查看数据存储是否存在哈希、指纹等机制保障存储的完整性
Check if there is a hash mechanism in the data storage to ensure the integrity of the storage存储内容被哈希处理,完整性得到保障
Stored data is hashed and integrity is guaranteed.将交易按照默克尔树的形式进行哈希并存储于区块
Bitcoin hashes transactions in the form of Merkel trees and stores them in blocks.是
Y数据保密性
Data confidentiality存储保密性
Storage Confidentiality查看机密数据的存储
是否加密
Check if the storage of confidential data is encrypted数据存储不是以明文格式
Data is not stored in plaintext format.数据存储是以明文的16进制形式进行存储,方便查询和验证
Bitcoin data storage is stored in plaintext in hexadecimal form, which is convenient for query and verification.否
N账本功能
Ledgerfunction数据抗抵赖
Data non-repudiation查看账本中的交易数据来源是否有效
Check if the transaction data in the ledger is signed交易被各个参与方签名,使交易可溯源,以达到抗抵赖的作用。
The transaction is signed by each participant, so that the transaction can be traceable to achieve the role of non-repudiation.区块链系统通过对交易数据进行签名达到了数据
抗抵赖的作用
Bitcoin achieves data non-repudiation by signing transaction data.是
Y账本数据同步
Ledger data synchronization查看是否有完全节点,
节点间存储账本数据
是否一致
Check if there is a full node, store all data in the ledger全节点中同步了账本中所有的数据,可以通过全节点得到区块链数据的完整副本
All the data in the ledger is synchronized in the full node. A complete copy of the blockchain data can be obtained from full nodes.区块链系统中存在同步了账本所有数据的全节点,并能对同步过程中发现的数据错误予以检测及确认
There are full nodes in the Bitcoin system that synchronize all the data of the ledger.是
Y账本数据幂等
Ledger data idempotentce查看账本信息中检索同样的数据结果是否一致
Check if the results of retrieving the same data
are consistent在查询相同记录时具有
相同的结果,确保
数据的一致性
Ensure data consistency by querying the same records with the same results.区块链系统存入账本的数据均通过共识,账本数据具有幂等性
The data of Bitcoin deposited in the ledger has passed the consensus, and ledger data has idempotency.是
Y表 7 区块链头信息及长度限制
Table 7. Information and length limit of Blockchain Header
数据项
Items用途
Use大小(字节)
Size(byte)区块版本V
Version区块版本号
Block version number4 难度D
Difficulty Target用以标注挖矿难度
To indicate the difficulty of mining4 前区块哈希
PreH Pre-block hash基于区块中所有交易的256位hash值
Based on the 256-bit hash value of all transactions in the block32 默克尔树根M
Merkletree Root交易内容hash256值
The value of the transaction content 256-bit hash32 随机数N
Nonce用以调整当前区块头hash值
To adjust the current block head hash value4 时间戳T
TimestampUNIX时间戳A
UNIX timestamp4 表 8 区块链合约计算层测评
Table 8. Blockchain contract computing layer evaluation
类别
Categories测评项
Items实施
Implementation预期效果
Expected effectiveness实际测评结果说明
Description of actual evaluation results达标
Y/N身份鉴别
Identification执行身份验证
Performingentity authentication查看合约是否许可查看或限定执行者身份
Check if the contract can be viewed or qualify executor’s identity应对登录的用户进行身份标识和鉴别,身份标识具有唯一性,身份鉴别信息具有复杂度
The identification and authentication should be carried out for the logged-in user. The identification is required to be unique and complicated.在发布交易时,区块链会对执行者身份进行验证,因此可以控制执行合约的身份
When publishing a transaction, the blockchain verifies the executor’s identity, thus constraining the execution of contract.是
Y安全审计
Security audit行为事件审计
Behavioral event audit能否验证智能
合约的执行
Check if to verify the execution of smart contract应启用安全审计功能,审计覆盖到每个用户,对重要的用户行为和重要
安全事件进行审计
The security audit function should be enabled to cover every user over significant user actions and
security events.所有参与挖矿节点会
验证智能合约执行的
正确性
All nodes involved in mining can verify the correctness of smart contract execution.是
Y审计记录
Audit records是否记录了审计的
相关信息
Check if audit information is recorded审计记录应包括事件的日期和时间、用户、事件类型、事件是否成功等。应对审计记录进行保护,定期备份,避免受到未预期的删除、修改或覆盖等
The audit record should include the date and time of event, the executor, the type
of event, the state if the event was successful, etc. Audit records should
be protected and backed up regularly to avoid unexpected deletions, modifications or overwrites.区块中的交易记录了智能合约的执行时间、执行用户、执行的输入与输出
The transactions in the block record the execution time, the executors, the input and output of the smart contract.否
N恶意代码防范
Malicious code protection免受恶意代码攻击
Protection from
malicious code是否有免受恶意代码攻击的机制
Check if there is a mechanism to protect against malicious code应采用免受恶意代码攻击的技术措施或主动免疫可信验证机制及时识别入侵和病毒行为,并将其有效阻断。
It is necessary to adopt the technical measures to avoid the attack of malicious code or the trusted verification mechanism with active immunity to identify the intrusion and virus behavior in time and block it effectively.通过限定的寻址方式、
限定的指令集以及Docker等运行环境或其他机制使得本地计算机及区块链系统不会
受到影响
Local computers and blockchain systems do not be affected byrestricted addressing methods, limited instruction sets, operating platforms such as Docker, or other mechanisms.是
Y数据完整性
Data integrity传输完整性
Transmission integrity查看是否通过校验技术或密码技术保证
数据完整性
Check if data integrity is guaranteed by CRC or cryptography应采用校验技术或密码技术保证重要数据在传输过程中的完整性。
Verification technology or cryptography should be adopted to ensure the integrity of important data during transmission.存在单个节点的状态
更新记录
There are status updating records for individual nodes.是
Y数据保密性
Data confidentiality传输保密性
Transmission confidentiality查看是否通过密码技术保证数据保密性
Check if data onidenticality is guaranteed by cryptography.应采用密码技术保证重要数据
在传输过程中的保密性。
Cryptography should be adopted to ensure the confidentiality of important data during transmission.区块链系统不具备全网节点数量实时统计能力
The blockchain system does not have the real-time statistical ability on the number of nodes in the whole network.否
N表 9 区块链系统error审计分类
Table 9. Blockchain error audit classification
功能
Function接口函数
Interface function输出错误
Output error初始化错误
Initialization errorAppInit2_Cold() Winsock库、初始化完整性检测、钱包文件损坏等
Winsock Library, Initial Integrity Detection, Wallet File Damage, etc.交易错误
Transaction errorCheckTransaction() 检查交易时出错,如输入输出为空等交易格式错误
Errors in checking transactions, such as empty input and output, etc.AcceptToMemoryPool() 验证交易合理性并存入交易池时发生错误,如输入已经被花费等
Errors occur when validating the reasonableness of transactions
and storing them in the trading pool, such as input being spent, etc.CScriptCheck() 脚本签名错误
Script signature errorCheckInputs() 交易输入错误,如:交易总输入<总输出
Transaction input errors, such as: total transaction input <total outputCheckSignature() 检查签名时出错
Error in checking signature区块错误
Block errorWriteBlockToDisk() 将区块写入磁盘出错,如文件打开失败
Errors in writing blocks to disk, such as file opening failureReadBlockFromDisk() 从磁盘读出区块出错,如打开区块文件失败
Error reading block from disk, such as failure to open block fileDisconnectBlock() 断开区块链接时出错
Error while disconnecting block linksConnectBlock() 连接区块时出错,如资产提交时出错
Error connecting blocks, such as asset submissionCheckBlock() 检查区块时出错,如默克尔树根不匹配
Error checking blocks, such as Merkle root mismatchContextualCheckBlockHeader 检查区块头部信息是否出错,如块的时间戳太早
Check if block header information is wrong, such as block timestamp too earlyLoadBlockIndex() 加载区块索引出错,如将创世块写入磁盘失败
Error loading block index, such as failure to write Genesis block to disk共识错误
Consensus errorCheckBlockHeader() 工作量证明失败 Proof-of-work error AcceptBlock() 未找到工作量证明
Accepting blocks makes errors, such as failing to find proof-of-work网络错误
Network errorRecvLine() socket错误Socket error Read() 连接节点数据文件peer.dat读错误
Error in peer.dat reading of connection node data fileWrite() 连接节点数据文件peer.dat写错误
Error in peer.dat writing of connection node data fileConnect() 连接错误 Connection error ProcessMessage() 侦听并处理网络中的不同的消息时出错
Errors in listening for and processing different messages in the network远程过程调用
Remote procedure callJSONRPCError 远程过程调用请求、解析、参数等错误
Errors in remote procedure call requests, parsing, parameters, etc.表 10 区块链系统测评结果总结
Table 10. Summary of evaluation results of blockchain system
类别
Categories测评项
Items达标 √/× 比特币
Bitcoin以太坊
Ethereum超级账本
Hyperledger分布式对等网络测评
Distributed P2P network assessment软件容错
Software fault tolerance自我保护与自适应
Self-protection and self-adaptation√ √ √ 资源控制
Resource control并发连接限制
Concurrent connection restriction√ √ √ 连接超时限制
Connection timeout limit√ √ √ 身份鉴别
Identification节点接入控制
Node link control× × √ 分布式对等网络测评
Distributed P2P network assessment数据完整性
Data integrity单播通信防篡改
Anti-tampering of unicast× × × 广播通信防篡改
Multicast communication tamper-proof× × × 转发通信防篡改
Forwarding communication tamper-proof× × × 安全审计
Security audit网络状态获取更新
Network status get update× × √ 网络节点动态监测
Network node dynamic monitoring√ √ √ 分布式账本测评
Distributed ledgers assessment软件容错
Software fault tolerance账本格式规范性
Standardization of ledger√ √ √ 访问控制
Access control账本访问控制
Ledger access control× × √ 数据完整性
Data integrity存储完整性
Storage integrity√ √ √ 数据保密性
Data confidentiality存储保密性
Storage confidentiality× × × 账本功能
Ledger function数据抗抵赖
Data non-repudiation√ √ √ 账本数据同步
Ledger data synchronization√ √ √ 账本数据幂等
Ledger data idempotence√ √ √ 共识机制测评
Consensus mechanism assessment资源控制
Resource control共识资源测评
Consensus Resource Control√ √ √ 备份与恢复
Backup and recovery实时备份
Real-time backup√ √ √ 系统热冗余
System hot redundancy√ √ √ 共识效果
Consensus effect共识容错性
Consensus fault tolerance√ √ √ 共识有效性
Consensus effectiveness√ √ √ 共识结果一致性
Consensus Consistency√ √ √ 合约计算层测评
Contract computing layer assessment身份鉴别
Identification执行身份验证
Performing entity authentication√ √ √ 安全审计
Security audit行为事件审计
Behavioral event audit√ √ √ 审计记录
Audit records× × × 恶意代码防范
Malicious code protection免受恶意代码攻击
Protection from malicious code√ √ √ 数据完整性
Data integrity传输完整性
Transmission integrity√ √ √ 数据保密性
Data confidentiality传输保密性
Transmission confidentiality× × × 统计
Statistics达标个数
Number of qualified items19
Nineteen19
Nineteen22
Twenty-two -
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