CN113935736A - Mobile terminal block chain safe transaction system - Google Patents
Mobile terminal block chain safe transaction system Download PDFInfo
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- CN113935736A CN113935736A CN202111180542.8A CN202111180542A CN113935736A CN 113935736 A CN113935736 A CN 113935736A CN 202111180542 A CN202111180542 A CN 202111180542A CN 113935736 A CN113935736 A CN 113935736A
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- G06Q20/00—Payment architectures, schemes or protocols
- G06Q20/38—Payment protocols; Details thereof
- G06Q20/382—Payment protocols; Details thereof insuring higher security of transaction
- G06Q20/3829—Payment protocols; Details thereof insuring higher security of transaction involving key management
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- G—PHYSICS
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- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q20/00—Payment architectures, schemes or protocols
- G06Q20/04—Payment circuits
- G06Q20/06—Private payment circuits, e.g. involving electronic currency used among participants of a common payment scheme
- G06Q20/065—Private payment circuits, e.g. involving electronic currency used among participants of a common payment scheme using e-cash
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Abstract
The invention discloses a mobile terminal block chain safe transaction system, wherein a mobile terminal application program module provides interaction for a user, acquires user requirements, and completes functions of wallet creation, transaction sending, information receiving and mobile terminal; the trusted environment module completes encryption and decryption operation, generation of encryption and decryption keys and security file operation; the security storage module stores the encrypted private key in a TEE side security file, so that the private key can be well protected from leakage even if the equipment is damaged; the transaction signature module carries out RLP serialization coding on the transaction data structure, calculates a hash value and a signature and inserts the hash value and the signature into the transaction; the network agent module calls an api interface of the electronic money network according to the requirements of the user, and correctly returns data to the client, and also comprises an access module of a private chain. The invention ensures that the private key is not easy to flow out, has high safety, ensures the safety of the private key after the equipment is broken and dismantled, and improves the safety and the reliability of the traditional hardware wallet.
Description
Technical Field
The invention relates to the field of digital currency and the field of block chains, in particular to a TrustZone-based mobile terminal block chain secure transaction system.
Background
Bitcoin is e-cash like e-mail, and both parties to the transaction need a "bitcoin wallet" like e-mail and a "bitcoin address" like e-mail address. Like sending and receiving e-mails, the sender pays the bitcoin directly to the other party according to the address of the receiver through a computer or a smart phone. The development of the bitcoin trading platform is not different from the development of the traditional website, anyone can call the ready-made PHP library on the open source website to open the bitcoin trading platform, and any bitcoin trading platform can be a live target of hacker attack. If developers do not perform security-based reinforcement protection during development, sensitive data of users may be illegally intercepted.
To address the security issues of traditional software wallets, hardware wallets have been produced. A hardware wallet is an application that manages digital currency based on blockchain technology, such as ethernet, and generally provides wallet address creation, transfer, transaction inquiry, and other functions. Hardware wallets can be divided into android hardware wallets and chip hardware wallets. As the name suggests, the android hardware wallet can be understood as an android mobile phone, unnecessary parts are removed, and the android mobile phone is specially used for wallet purposes after being modified by software. Hardware wallets are generally able to do network isolation, but android does not have system integrity protection, making it vulnerable to supply chain attacks and nefarious commissions. In addition, the android system itself can be problematic if security enforcement is not done. The chip hardware wallet is the mainstream product in foreign markets, and mainly programs wallet core logic directly on a chip system to keep wallet seeds inside the chip as a security feature. Although the chip hardware wallet provides security protection well, great inconvenience exists, for example, smooth instantaneity of transaction is difficult to achieve, carrying is inconvenient, potential safety hazards of loss exist, and even loss of some hardware wallets means permanent loss of account assets.
Therefore, the hardware wallet needs to solve the safety problems of inconvenient carrying, relatively complicated procedures and loss, improve the convenience of operation and carrying, simultaneously maintain the isolated secure signature environment and even higher privacy degree of the private key of the hardware wallet, and better ensure the data security and transaction security.
Disclosure of Invention
The invention aims to provide a mobile terminal block chain safe transaction system aiming at the corresponding defects of the prior art, and the hardware wallet is integrated in a server terminal, so that the operation simplicity and the carrying convenience are improved. The trusted execution environment is built and the private key is safely stored, so that the private key is isolated from a network, and the user application is isolated from a wallet, so that a hacker cannot find the position of a private key ciphertext even if the hacker makes physical attack or invades hardware in other ways, the privacy degree of the private key is improved, and the data and transaction safety is protected in multiple levels.
The purpose of the invention is realized by adopting the following scheme:
the invention discloses a mobile terminal block chain safe transaction system which comprises a mobile terminal application program module, a trusted environment module, a safe storage module, a transaction signature module and a network agent module, wherein the mobile terminal application program module mainly provides interaction for a user and acquires user requirements; the trusted environment module mainly uses an OP-TEE architecture; the security storage module adopts a security storage technology based on a TEE side framework, the encryption and decryption processes are completed in a trusted environment, the generation of encryption and decryption keys is also performed in an OP-TEE, the private key is encrypted and stored in a TEE side security file, and the private key can be well protected from leakage even if equipment is damaged.
And the trusted environment module finds the security file in which the private key is stored through dirf.db, decrypts the private key in a trusted environment and transmits the private key to the transaction signature module for transaction signature.
The transaction signature module generates a signature data packet containing a message from a user account, the data packet storing a message to be sent from one account to another account on the blockchain, first creates a transaction data structure (nonce, gasridge, gasLimit, to, value, data, V, R, S) comprising nine fields, then generates an RLP encoded transaction serialized message and calculates a Keccak256 hash value of the message, calculates an ECDSA signature and signs the hash using the sender' S private key, and finally inserts the calculated R and S values of the ECDSA signature in the transaction.
The mobile terminal application program module provides an interactive terminal and an interface for a user, when the user opens a wallet on a mobile phone for transaction, the network agent module transmits a transaction structure body into a signature server in an ssh mode, an REE side OP-TEE driver transmits data into the trusted environment module, the OP-TEE driver analyzes the data and recombines the data, the data which needs to be transmitted into the TEE side is loaded into a shared memory, a security monitoring mode is triggered to call the data and transmits the data to the TEE, meanwhile, the REE side executes a CA (certificate Authority) to open a session and call a command in a TA (trusted application protocol), a function is called to start processing an operation request for calling the TA command according to the created session content obtained by a session ID (identity), then the TA obtains the hash value number of a file name where a private key is located, opens a security file in the security storage module according to the security file number, reads the head of the security file and establishes a node tree of the security file, then, the security file can be read, the information needed for decrypting the ciphertext data can be obtained, the session ID and the running context of the TA can be obtained when the private key is read, and the authority can be checked. And then calling a function to realize the operation of reading Data and returning an execution result to the CA to obtain raw Data, ending the session, and finishing the transaction of the digital currency through the transaction signature module.
The network agent module is a component of a desktop client, and has the functions of calling an api interface of an electronic money network (including Ether, Bitty, Lett and the like) according to the requirements of a user, correctly returning data to the client and also comprising an access module of a private chain.
The invention has the advantages that: based on the OP-TEE trusted execution environment, the function call is initiated by the CA, the TA performs specific function realization and returns data to the CA, so that the functions and data in the security module can be called only by the user application program with the same corresponding uuid on the TEE side, the security module is isolated from the user application layer, the TEE side data is safer, the private key cannot be attacked and stolen by malicious application, the transaction signature also becomes safer, and a secure trusted execution environment on the TEE side is formed. After the first layer of security protection is built through the trusted environment, the private key at the TEE side is stored by using the security storage technology based on the TEE side framework, the encryption and decryption processes are all completed in the trusted environment, and the generation of the encryption and decryption keys is also performed in the OP-TEE, so that the security of the private key and the security of data of the private key are ensured. The invention realizes 'hardware wallet' in a software mode based on the signature server TrustZone, integrates the hardware wallet in the server terminal, and still maintains the isolated secure signature environment of the hardware wallet and even higher privacy degree of a private key on the basis of improving the operation simplicity and carrying convenience degree. Through the scheme, the safety requirement and the convenient requirement of the hardware wallet can be effectively met.
Compared with the existing hardware wallet, the wallet solves the problems of inconvenient carrying and complex operation of the hardware wallet, simplifies the transaction under the condition of ensuring higher safety, and greatly improves the timeliness of the transaction. The hardware wallet is used as a financial transaction tool, the requirements on safety and reliability are higher than those of common products, and aiming at the problems that the safety of a private key is threatened after equipment is broken and disassembled and the private key is easy to flow out of a chip and has low safety degree in the conventional hardware wallet, the private key disclosed by the invention is encrypted and stored in a safety file by using a safety storage technology, so that the private key is ensured not to flow out easily, and the safety of the conventional hardware wallet is improved.
Drawings
FIG. 1 is an overall architecture of the mobile end block chain secure transaction system of the present invention based on an OP-TEE digital wallet;
FIG. 2 is a frame of a security driver in the mobile end block chain secure transaction system OP-TEE according to the present invention;
fig. 3 is a processing flow of the trusted execution environment of the mobile-end blockchain secure transaction system according to the present invention.
Detailed Description
Referring to fig. 1 to fig. 3, the present embodiment discloses a mobile end block chain secure transaction system, which includes a mobile end application module (namely, an REE side CA module), a trusted environment module (namely, a TEE side TA module), a secure storage module, a transaction signature module, and a network agent module, where the mobile end application module is a hardware wallet user-oriented application layer program, and mainly provides interaction for a user, obtains user requirements, and completes functions of wallet creation, transaction transmission, information reception, and mobile end. The trusted environment module completes encryption and decryption operation, generation of encryption and decryption keys, security file operation and the like by using an OP-TEE framework.
The security storage module adopts a security storage technology based on a TEE side framework, stores the encrypted private key in a TEE side security file, and can well protect the private key from being leaked even if equipment is damaged. And when a file updating function is called, another random number is generated to serve as an IV value of the encrypted FEK and is stored in the head of the security file, and the IV value is replaced by the new random number each time the file is updated. After an interface function is called in the TA to create the security file, the initialization data is encrypted and written into the security file, and then the node tree information of the whole security file is updated until the creation of the security file is completed. In order to find the security file through the dirf.db file subsequently, the content of the dirf.db file needs to be updated, mainly the file path interface data in the data area of the dirf.db file is updated. And the trusted environment module finds the security file in which the private key is stored through dirf.db, enters an OP-TEE kernel space in the TA to execute an opening operation, decrypts the private key in the trusted environment and transmits the private key to the transaction signature module for transaction signature.
The transaction signature module comprises an RLP (Recursive Length Prefix) coding sequence module, a hash module and an ECDSA signature module. The signature data packet containing the message sent from the user account stores the message to be sent from one account to another account on the blockchain, and accordingly a transaction data structure (nonce, gasridge, gasLimit, to, value, data, V, R, S) containing nine fields is generated, then the RLP encoding serialization module generates an RLP encoded transaction serialized message from the transaction data structure, the hash module calculates the Keccak256 hash value of the message, the ECDSA signature module calculates the ECDSA signature and signs the hash using the private key of the sender, and finally inserts the calculated R and S values of the ECDSA signature in the transaction.
The network agent module is a component of a desktop client and is mainly responsible for calling an api interface of an electronic money network (including Ether, Bitty, Lett and the like) according to the requirements of a user, correctly returning data to the client and also comprising an access module of a private chain.
And the built OP-TEE in the trusted environment module and a Linux application program of a hardware wallet system are integrated in the raspberry pi 3B.
The invention mainly protects the safe storage of the secret key, and if the secret key is stored in a safe file in an encrypted manner by using a safe storage technology, the secret key is not easy to flow out, the safety degree is high, and the safety of the secret key after the equipment is broken and dismantled is also ensured.
The working principle of the invention is as follows: when a user opens a wallet on a mobile phone to trade, a trading structure body is transmitted into a signature server in an ssh mode, an OP-TEE driver on an REE side transmits data into a trusted side, the OP-TEE driver analyzes and recombines the data, the data which needs to be transmitted into the TEE side is loaded into a shared memory, a security monitoring mode call (smc) is triggered to transmit the data to the TEE, the REE side executes a CA to open a session, calls a command in the TA to obtain the created session content according to a session ID, calls a TEE _ TA _ invoke _ command function to start processing an operation request for calling the TA command, the function corresponding to the VOIn _ command _ entry _ Point executes corresponding operation according to different command IDs, then the TA executes and reads a hash value number of a file name of a corresponding private key in a dirf.db file, opens a security file after the security file number is obtained, and reads a head part of the security file, acquiring root node information, establishing a node tree of the security file, starting reading the security file, decrypting ciphertext data in a certain block in a data area, needing to use an IV value in a corresponding node ID, and storing a corresponding FEK (field encryption key) which is encrypted at the head of the security file, and acquiring a session ID and an operation context of a TA (trusted application) and checking authority when reading a private key. And then calling ree _ fs _ read function to realize the operation of reading Data and returning the execution result to CA, obtaining raw Data, ending the session and completing the transaction of digital currency through transaction signature.
The present invention has been described in detail with reference to the preferred embodiments, but the scope of the present invention is not limited thereto. For example, the information stored in the secure storage module may be adjusted according to actual requirements, but still fall within the scope of the present invention; the signature algorithm and the hash algorithm used by the transaction signature module are not limited to the ECDSA signature algorithm and the Keccak256 hash algorithm, and other signatures and hash algorithms also belong to the protection scope of the invention; it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (7)
1. A mobile-end block chain secure transaction system is characterized in that: comprises a mobile terminal application program module, a trusted environment module, a secure storage module, a transaction signature module and a network agent module,
the mobile terminal application program module is a program of a hardware wallet facing to a user application layer, and is mainly used for providing interaction for a user, acquiring user requirements, and completing functions of wallet creation, transaction sending, information receiving and mobile terminal;
the trusted environment module completes encryption and decryption operation, generation of encryption and decryption keys, security file operation and the like by using an OP-TEE architecture;
the security storage module stores the encrypted private key in a security file at the TEE side by adopting a security storage technology based on a TEE side framework, so that the private key can be well protected from leakage even if equipment is damaged;
the transaction signature module carries out RLP serialization coding on a transaction data structure, calculates a hash value and a signature and inserts the hash value and the signature into a transaction;
the network agent module calls an api interface of the electronic money network according to the requirements of a user, and correctly returns data to a client, and also comprises an access module of a private chain.
2. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the mobile terminal application program module comprises a wallet establishing module, a wallet managing module, a transaction information acquiring module, a transaction sending module, a transaction processing module, an information receiving module and each function of the mobile terminal,
the wallet creating module is connected to the secure storage module, generates a private key after creating a wallet according to user requirements, and stores the private key in a secure file by the secure storage module;
the transaction information acquisition module comprises a key-in module and a code scanning module and is used for acquiring a transaction destination address and amount;
and clicking the next step to carry out transaction, calling a private key at the TEE side of the trusted environment to carry out offline digital signature, finishing the signature by the transaction signature module, then sending the signature to the node server by the network agent module, and returning information to respond.
3. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the security storage module stores the encrypted private key in a security file at the TEE side by adopting a security storage technology based on a TEE side framework, so that the private key can be protected from being leaked even if equipment is damaged;
the safe storage module mainly completes the function of storing the private key and comprises a db file creating module, a safe file creating module and a db file updating module, the safe storage module is connected to the trusted environment module and executes safe file operation in the trusted environment, the trusted environment module finds the safe file with the private key through the db file, decrypts the private key in the trusted environment and transmits the private key to the transaction signature module for transaction signature.
4. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the transaction signature module comprises a transaction signing module and a signature verification module, wherein,
the transaction signing module comprises an RLP coding sequence module, a hash module and a signature generation module;
the transaction signature module is connected to the mobile terminal application program module, and when a user creates a wallet and initiates a transaction, the transaction can be sent out by the network agent module after being signed by the transaction signature module; when the user receives a transaction, the transaction can be processed after the transaction is signed and verified by the transaction signature module.
5. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the network agent module is a component of a desktop client, and mainly comprises an api interface module, a public link access module and a client interaction module which are required by a user and connected with an electronic money network, and also comprises a private link access module;
the network agent module is connected with the transaction signature module, the transaction is sent to the node after the local signature is finished, and the private key is stored in a local hardware wallet and does not need to be stored in the node wallet.
6. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the trusted execution module is connected with the mobile terminal application program module and the safe storage module to complete safe operation;
the trusted execution module provides a secure storage function for the secure storage module by using an OP-TEE architecture.
7. The mobile-end block chain secure transaction system according to claim 1, characterized in that: the mobile terminal application program module, the trusted environment module, the secure storage module, the transaction signature module and the network agent module are all integrated on an OP-TEE OS.
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| US20200028693A1 (en) * | 2018-07-17 | 2020-01-23 | Huawei Technologies Co., Ltd. | Verifiable Encryption Based on Trusted Execution Environment |
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- 2021-10-11 CN CN202111180542.8A patent/CN113935736A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106506472A (en) * | 2016-11-01 | 2017-03-15 | 黄付营 | A kind of safe mobile terminal digital certificate method and system |
| CN110492990A (en) * | 2018-05-15 | 2019-11-22 | 华为技术有限公司 | Private key management method, apparatus and system under block chain scene |
| US20200028693A1 (en) * | 2018-07-17 | 2020-01-23 | Huawei Technologies Co., Ltd. | Verifiable Encryption Based on Trusted Execution Environment |
Non-Patent Citations (1)
| Title |
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| 林知共创: "【OP-TEE】安全存储", HTTPS://BLOG.CSDN.NET/ THANKSGINING/ARTICLE/DETAILS/111564548, 23 December 2020 (2020-12-23), pages 1 - 3 * |
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