CN111698093B - Digital timestamp issuing and verifying method based on PKI system - Google Patents
Digital timestamp issuing and verifying method based on PKI system Download PDFInfo
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- CN111698093B CN111698093B CN202010531678.8A CN202010531678A CN111698093B CN 111698093 B CN111698093 B CN 111698093B CN 202010531678 A CN202010531678 A CN 202010531678A CN 111698093 B CN111698093 B CN 111698093B
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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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- 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
- H04L63/123—Applying verification of the received information received data contents, e.g. message integrity
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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
- H04L9/3236—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 using cryptographic hash functions
- H04L9/3239—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 using cryptographic hash functions involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD
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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
- H04L9/3263—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 certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements
- H04L9/3268—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 certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements using certificate validation, registration, distribution or revocation, e.g. certificate revocation list [CRL]
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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
- H04L9/3297—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 time stamps, e.g. generation of time stamps
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- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
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- General Engineering & Computer Science (AREA)
- Storage Device Security (AREA)
Abstract
The invention discloses a digital timestamp issuing and verifying method based on a PKI system, which comprises the following specific steps of: acquiring a digital certificate and a timestamp service provided by an authentication center; creating a message digest value of the medical record document based on a hash function; carrying out encryption operation on the message digest value by using private key data in the digital certificate according to an encryption principle to create a digital signature and sending the digital signature to a timestamp authority; decrypting the digital signature by using public key data in the digital certificate, and encrypting additional timestamp information in combination with private key data corresponding to the digital certificate to generate a new digital signature; the timestamp authority sends the new digital signature back to the sender along with its own digital certificate. The invention fully considers the time stamp authentication requirement of the medical record document digital signature, can better solve the problem that the time stamp authority possibly exists in the digital signature process and the user communicates with each other to change the credibility of the signature, and enhances the non-repudiation of the data.
Description
Technical Field
The invention relates to the field of digital signature information security, in particular to a digital timestamp issuing and verifying method based on a PKI system.
Background
With the increasing popularization of internet concepts in recent years, on the basis of meeting all diagnosis, treatment, laws and management requirements, the electronic medical records gradually replace the traditional paper medical records, and electronic management of personal health states and medical health care information is realized. The development of digital signature technology has been progressed, wherein the undeniability of the digital signature by the physician is one of the important roles of the digital signature. When a medical dispute occurs, evidence is necessary to verify the identity of the party or medical technician, but identity information alone is not sufficient because the responsible party or medical technician may tamper with the medical record content afterwards, and to prevent this, time stamp information approved by law and third parties must be added at the time of signature.
Much work has been focused on the process of issuing and verifying timestamps. For example, a simple time stamp issuing step includes three steps: the user sends a medical record document W to the timestamp authority TSA, which appends the current time T after W and the document' S unique identification ID to form a new electronic signature S, TSA and sends S to the user. However, the timestamp protocol is not feasible in implementation, and relates to the confidentiality problem of medical record documents W, the file integrity problem in the uploading and storing processes, the resource utilization problem caused by overlarge files, and the signature credibility problem that TSA and a user are fraudulently communicated possibly; based on the steps, relevant scholars improve, a TSA credible timestamp scheme is provided, the abstract value H of the document replaces the original medical record document W, and a digital signature technology is applied in the transmission process, so that the problems of confidentiality, integrity and resource utilization rate are solved well, but the problem that the credibility of the signature is changed due to the fact that a timestamp authority mechanism and a user are communicated in the digital signature process is not solved technically.
Disclosure of Invention
The invention aims to solve the problems in the prior art by providing a digital timestamp issuing and verifying method based on a PKI system.
In order to achieve the purpose, the invention provides the following technical scheme: a digital timestamp issuing and verifying method based on a PKI system comprises the following steps:
step (1): acquiring a digital certificate provided by a PKI (public key infrastructure) certification center CA and a timestamp service provided by a timestamp authority TSA (certificate of authority);
step (2): creating a message digest value h of the XML medical record document W based on a hash function;
step (1 a): a doctor applies for a digital certificate from a certificate authority CA to obtain a legal identity;
step (1 b): the CA center authorizes the TSA to provide a time stamp service, issues a digital certificate for the TSA and supervises the action of the TSA (the digital certificate of the TSA can be revoked if necessary);
and (3): encrypting the message digest value h by using private key data in the digital certificate according to an encryption principle to create a digital signature s ═ SIGDOctor (h), and sending (s, h) and the digital certificate to the TSA;
and (4): the TSA decrypts the digital signature S by using the public key data in the digital certificate, and adds timestamp information to encrypt the digital signature S in combination with the private key data corresponding to the digital certificate to generate a new digital signature S;
step (4 a): the TSA decrypts the received digital signature by using public key data in the digital certificate of the sender in combination with an encryption algorithm to obtain a message digest value H;
step (4 b): comparing the decrypted message digest value H with the original message digest value H; if not, sending error information to the requester; if the time t is equal to the time t, the serial number ID of the timestamp request and the message digest H, the whole data block formed by the accurate time t when the request is received, the serial number ID of the timestamp request and the message digest H is combined with a private key corresponding to the digital certificate to be encrypted to form a new digital signature S ═ SIGTSA(ID,H,t)；
And (5): the TSA sends the new digital signature S and the digital certificate of the TSA back to the sender, and performs local saving and backup;
and (6): the sender verifies the credibility of the TSA digital timestamp through a PKI mechanism;
step (6 a): the sender verifies the credibility of the TSA digital certificate through a PKI mechanism, if the TSA digital certificate passes the verification, the credibility of the digital timestamp is verified, and the digital signature S with the timestamp is stored;
step (6 b): when the sender needs to verify the time when the XML medical record document W was produced, the PKI certificate authority CA can verify the authenticity of the timestamp using the public key in the TSA digital certificate to see if the document W is legally valid.
The invention has the beneficial effects that: the digital timestamp issuing and verifying method based on the PKI system fully considers the timestamp authentication requirement of medical record document digital signature, can better solve the problem that the credibility of signature is changed by the fact that a timestamp authority TSA communicates with a user in a digital signature process, and enhances the non-repudiation of data.
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FIG. 1 is a flow chart of the present invention.
Detailed Description
The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more readily understand the advantages and features of the present invention and to clearly and clearly define the scope of the invention.
Example 1: referring to fig. 1, the present invention provides a technical solution: a digital time stamp issuing and verifying method based on a PKI system comprises the following steps: the invention has the following implementation steps:
(1) acquiring a digital certificate provided by a PKI (public key infrastructure) certification center CA and a timestamp service provided by a timestamp authority TSA (certificate authority);
(1a) a doctor applies for a digital certificate to a certification authority CA to obtain a legal identity;
(1b) the CA center authorizes the TSA to provide a time stamp service, issues a digital certificate for the TSA and supervises the behavior of the TSA (the digital certificate of the TSA can be revoked if necessary);
(2) establishing a message abstract value h of the XML medical record document W based on a hash function;
(3) encrypting the message digest value h by using private key data in the digital certificate according to an encryption principle to create a digital signature s ═ SIGdotor (h), and sending (s, h) and the digital certificate to the TSA;
(4) the TSA decrypts the digital signature S by using the public key data in the digital certificate, and adds timestamp information to encrypt the digital signature S in combination with the private key data corresponding to the digital certificate to generate a new digital signature S;
(4a) the TSA decrypts the received digital signature by using public key data in the digital certificate of the sender in combination with an encryption algorithm to obtain a message digest value H;
(4b) comparing the decrypted message digest value H with the original message digest value H; if not, sending error information to the requester; if the time t is equal to the time t, the serial number ID of the timestamp request and the message digest H, the whole data block formed by the accurate time t when the request is received, the serial number ID of the timestamp request and the message digest H is combined with a private key corresponding to the digital certificate to be encrypted to form a new digital signature S ═ SIGTSA(ID,H,t)；
(5) The TSA sends the new digital signature S and the digital certificate of the TSA back to the sender, and performs local saving and backup;
(6) the sender verifies the credibility of the TSA digital timestamp through a PKI mechanism;
(6a) the sender verifies the credibility of the TSA digital certificate through a PKI mechanism, if the verification is passed, the credibility of the digital timestamp is proved, and the digital signature S with the timestamp is stored;
(6b) when the sender needs to verify the time when the XML medical record document W is produced, the PKI certificate authority CA can verify the authenticity of the timestamp using the public key in the TSA digital certificate to see if the document W is legally valid.
In order to verify the effectiveness of the method in the patent, based on the digital timestamp issuing and verifying process, a medical record timestamp issuing and verifying system is designed by depending on a C # development environment and a Visual Studio2010 operation environment, and the core of the medical record timestamp issuing and verifying system is to provide timestamp service for medical staff and facilitate the timestamp adding of medical record documents. And the medical record timestamp adopts a streaming Socket as a transmission basis and performs packaging transmission on the information of the request and the response. The medical record timestamp system adopts a client/server structure, and medical staff can access a TSA service program of a server side through an IP address of a login server to obtain a signature timestamp or check the authenticity and the validity of the timestamp online.
The client program mainly provides an interface convenient for medical staff to operate so as to complete the request of the timestamp service and the processing of the timestamp response information. The medical record document to be stamped is subjected to abstract operation firstly, in order to ensure the transmission safety of data, an abstract value is signed, correct timestamp service request format data is formed finally and is sent to a server side, and then the medical record document is waited for processing. When the response information is returned, the correctness analysis and the integrity verification of the result data and the verification of the certificate credibility and the validity of the timestamp server are required, and finally the obtained data is correspondingly processed according to different applications.
The server-side program, i.e., the timestamp server, is the core of the whole system, so the system functions are mainly concentrated on the server side, and mainly include functions of responding to a client-side timestamp request, issuing a timestamp, storing timestamp information, and the like. The server side receives a plurality of users who receive the time stamp requests, and for safety, the server side has a plurality of keys for signature, and the key management module can safely and effectively manage the keys. The database module is used for saving the time stamp and other relevant information for receiving the request of the client time stamp verification in the future. The time source module can provide accurate and trusted time. The verification service module is responsible for verifying the identity of the requester and the like.
NET has been implemented to provide great convenience to encoding personnel, the namespace for implementing these algorithms is System security. The implementation of the hash function maps binary strings of arbitrary length to small binary strings of fixed length. The hash value is a unique and compact numerical representation of a piece of data, and if a piece of plaintext is hashed, one punctuation mark in the plaintext is changed, and the subsequent hash values generate different values. Therefore, it is computationally almost impossible to find two different inputs that are hashed to the same value. Therefore, the hash value of the data can verify the integrity of the data.
Public key cryptography uses a private key that is kept secret from unauthorized users and a public key. Data encrypted with the public key can only be decrypted with the private key, while data signed with the private key can only be verified with the public key. The public key can be used by anyone; the key is used to encrypt data to be sent to the holder of the private key.
The medical record timestamp issuing and verifying system mainly realizes the following functions. First, the use of a hash function to randomly generate a public key and a private key, the key being in the form of an XML extensible markup language, which identifies a document by dividing it into many parts, is a way to store data in a simple text format, meaning that it can be read by any computer, and returns a string of characters. Second, the required message digest MD is generated for the plaintext information to be encrypted. Thirdly, the generated private key d is used for carrying out encryption operation on the generated message digest according to the encryption principle of the SA algorithm, and a digital signature is obtained. Fourth, the identity of another entity is verified and the integrity of the data is protected. That is, when a message is digitally signed using public key data, the sender first applies a hash function to the message to create a digest of the message. The sender then encrypts the message digest using the sent private key to create a sender's personal signature, since this private key uniquely identifies the sender, and upon receipt of the message and signature, the recipient decrypts the signature using the sender's public key to recover the message digest and hashes the message using a uniform hashing algorithm used by the sender. If the message digest computed by the recipient exactly matches the message digest received from the sender, the recipient may determine that the message is from the sender.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.
Claims (1)
1. A digital timestamp issuing and verifying method based on a PKI system is characterized by comprising the following steps:
step (1): acquiring a digital certificate provided by a PKI (public key infrastructure) certification center CA and a timestamp service provided by a timestamp authority TSA (certificate of authority);
step (1 a): a doctor applies for a digital certificate to a certification authority CA to obtain a legal identity;
step (1 b): the CA center authorizes the TSA to provide a timestamp service, issues a digital certificate for the TSA, and supervises the behavior of the TSA;
step (2): establishing a message abstract value h of the XML medical record document W based on a hash function;
and (3): encrypting the message digest value h by using private key data in the digital certificate according to an encryption principle to create a digital signature s ═ SIGdotor (h), and sending (s, h) and the digital certificate to the TSA;
and (4): the TSA utilizes public key data in the digital certificate to decrypt the digital signature S, and adds timestamp information to generate a new digital signature S by combining with the encryption of private key data corresponding to the digital certificate;
step (4 a): the TSA decrypts the received digital signature by using the public key data in the digital certificate of the sender in combination with an encryption algorithm to obtain a message digest value H;
step (4 b): comparing the decrypted message digest value H with the original message digest value H; if not, sending error information to the requester; if the time t is equal to the time t, the serial number ID of the timestamp request and the message digest H, the whole data block formed by the accurate time t when the request is received, the serial number ID of the timestamp request and the message digest H is combined with a private key corresponding to the digital certificate to be encrypted to form a new digital signature S ═ SIGTSA(ID,H,t)；
And (5): the TSA sends the new digital signature S and the digital certificate of the TSA back to the sender, and performs local saving and backup;
and (6): the sender verifies the credibility of the TSA digital timestamp through a PKI mechanism;
step (6 a): the sender verifies the credibility of the TSA digital certificate through a PKI mechanism, if the verification is passed, the credibility of the digital timestamp is proved, and the digital signature S with the timestamp is stored;
step (6 b): when the sender needs to verify the time when the XML medical record document W was produced, the PKI certificate authority CA can verify the authenticity of the timestamp using the public key in the TSA digital certificate to see if the document W is legally valid.
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| CN112465502A (en) * | 2020-11-11 | 2021-03-09 | 中国农业银行股份有限公司上海市分行 | Method for deploying digital time stamp offline |
| CN112395620B (en) * | 2020-11-19 | 2024-01-30 | 四川泰富地面北斗科技股份有限公司 | Trusted time stamp implementation method based on trusted time |
| CN113130031B (en) * | 2021-05-18 | 2024-07-30 | 中南大学湘雅三医院 | PKI-based inter-hospital electronic medical record interaction system, method, equipment and storage medium |
| CN113536391A (en) * | 2021-06-29 | 2021-10-22 | 上海浩霖汇信息科技有限公司 | Electronic certificate, digital certificate class black box authentication method, system and related products |
| CN114362955A (en) * | 2021-12-01 | 2022-04-15 | 零信技术(深圳)有限公司 | Software code cloud digital signature method, system, device and storage medium |
| CN114499875B (en) * | 2021-12-31 | 2024-05-10 | 兴业消费金融股份公司 | Service data processing method, device, computer equipment and storage medium |
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