A quantum attack-resistant electronic signature method and system

Abstract

The present invention provides an electronic signature method and system resistant to quantum attacks, which obtains a signature application and performs identity authentication on the applicant for signature; receives electronic seal information and a document to be signed, generates electronic signature document information, calculates the ciphertext and message authentication code of the electronic signature document information by using a shared key, and feeds back the corresponding ciphertext and message authentication code to the applicant for signature so that the applicant can decrypt and obtain the document; calculates the message digest of the electronic signature document information, calculates the authentication code of the message digest by using another shared key, submits the message digest and the authentication code to a third party for verification, waits for the verification result of the third party, and the comparison result of the third party on the document and the message digest, when both the verification result and the comparison result are passed, the applicant for signature obtains the electronic signature information after the third party performs a symmetric key digital signature; the present invention can reduce the computational complexity while ensuring the resistance to quantum attacks.

Description

Technical Field

[0001] The present invention belongs to the technical field of encryption communication of quantum cryptographic networks, and specifically relates to an electronic signature method and system resistant to quantum attacks. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] With the rapid development of information technology, electronic signatures have emerged to improve the reliability and convenience of online information. Electronic signatures are not digital images of written signatures and seals, but exist in the form of electronic codes. With electronic signatures, recipients can transmit files over the Internet and easily verify the sender's identity and signature. It can also verify whether the original text of the file has changed during the transmission process. Electronic signatures are conducive to identifying the identity of the signer of the electronic document, ensuring the integrity of the document, and ensuring the authenticity, reliability and non-repudiation of the document.

[0004] Currently, most electronic signatures use PKI technology, but the asymmetric key encryption algorithm used by PKI technology is computationally secure. In the face of the foreseeable research and construction of quantum computers, cryptographic systems based on computational complexity are unsafe and pose high security risks.

[0005] According to the inventors, some researchers also want to improve the above problems. However, the current improvement methods mostly adopt more complex signature or encryption methods. For example, the patent document CN109560935A provides a quantum computing-resistant signature method and signature system based on a public asymmetric key pool. The quantum computing-resistant public key generated by the seal public key combined with the asymmetric key pool in the key card is used to hide the seal public key by publicizing the quantum computing-resistant public key, so as to realize the quantum computing-resistant characteristics of the electronic signature. However, in the signature encryption method provided by it, RSA signature is used once, symmetric encryption is used once, and RSA encryption is used once. The calculation amount is about twice that of the ordinary RSA signature method. Similarly, the calculation amount when decrypting and verifying the signature is also about twice that of the ordinary verification method. The calculation amount involved in signature and verification is large, which affects the communication data volume and efficiency. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes an electronic signature method and system that are resistant to quantum attacks. The present invention can reduce the computational complexity while ensuring resistance to quantum attacks.

[0007] According to some embodiments, the present invention adopts the following technical solutions:

[0008] An electronic signature method resistant to quantum attacks comprises the following steps:

[0009] Obtain the signature application and authenticate the identity of the applicant;

[0010] Receive the electronic seal ID information of the applicant who has passed the identity authentication and the encrypted document to be signed, review the authority of the applicant, generate electronic signature document information matching the authority, calculate the ciphertext and message authentication code of the electronic signature document information using the shared key, and feedback the corresponding ciphertext and message authentication code to the applicant so that the applicant can decrypt and obtain the document;

[0011] Calculate the message digest of the electronic signature document information, use another shared key to calculate the authentication code of the message digest, submit the message digest and authentication code to a third party for verification, wait for the third party's verification result, and the third party's comparison result of the document and the message digest. When both the verification result and the comparison result are passed, the applicant can obtain the electronic signature information after the third party performs symmetric key digital signature.

[0012] As an optional implementation method, before obtaining a signature application and authenticating the identity of the applicant for signature, the applicant for signature needs to undergo registration verification. After passing the verification, a shared key is distributed to the applicant for subsequent encrypted communication.

[0013] As an optional implementation method, the specific process of obtaining a signature application and performing identity verification on the signature applicant includes:

[0014] Send a random number r1 to the person applying for signature;

[0015] Receive the message authentication code about the applicant's ID, random number r1, serial number n and shared key K calculated by the applicant using the unused shared key K with serial number n, and receive the serial number n and random number r2;

[0016] Read the shared key K with serial number n shared with the applicant for signature, verify the correctness of the message authentication code, and if correct, calculate the message authentication code related to r1, r2, serial number n and key K, send it to the applicant for signature, and wait for the verification result. If the verification passes, mark the shared key with serial number n as used.

[0017] As an optional implementation, the process of generating electronic signature document information matching the authority includes: packaging the electronic seal information and the signature applicant information into electronic signature data, stamping it on the document, and generating the electronic signature document information.

[0018] As an optional implementation, the specific process of a third party performing a symmetric key digital signature includes: using an unused key to calculate a message authentication code of the signature information as a symmetric key digital signature of the electronic signature document information, wherein the symmetric key digital signature includes information about the electronic signature document information, the time at that time, the serial number of the signature key used, and the key used for the digital signature.

[0019] As an optional implementation, multiple keys are distributed at once according to the length of the shared key used each time, and the shared keys are divided and numbered in synchronization order;

[0020] When the shared key is about to be used up, the two parties of the shared key use the unused shared key for identity authentication, redistribute the shared key using the quantum cryptography network, encrypt the newly distributed shared keys one by one using the same unused shared key distributed last time, resynchronize the sequential number storage, and delete all the shared keys distributed last time.

[0021] An electronic signature system resistant to quantum attacks, comprising:

[0022] The client device is configured to submit a signature application of the signatory, obtain the identity verification result, authenticate the electronic signature server, send the electronic seal ID and encrypt and send the document to be signed, use the message authentication code to verify the identity of the electronic signature server, if it is correct, decrypt the electronic signature information sent by it and verify the correctness, if it is correct, use the shared key with the trusted center to calculate the ciphertext and authentication code of the electronic signature document information, send them to the trusted center, and receive the final signed document;

[0023] The electronic signature server is configured to verify the identity of the applicant, review the authority of the applicant, package the received applicant information and electronic seal information to generate electronic signature data, affix it to the document, generate electronic signature document information, send the ciphertext and authentication code of the electronic signature document information to the client device, and calculate the message digest of the electronic signature document information and its authentication code, and send them to the trusted center;

[0024] The trusted center is configured to verify the identity of the electronic signature server using the authentication code of the electronic signature document information. If the verification is correct, the message digest is saved, and the electronic signature document information of the correct applicant is received, the message digest of the electronic signature document information is calculated, and compared with the stored message digest. If they are the same, the electronic signature document information is digitally signed with a symmetric key, the electronic signature information is generated, and it is encrypted and sent to the corresponding client device.

[0025] As an optional implementation, the trusted center is a third-party organization located at the quantum cryptography network terminal, and is provided with a true random number digital signature key library. The keys in the true random number digital signature key library are divided according to the length used for each digital signature and have different numbers.

[0026] As an optional implementation, the electronic signature server stores electronic seal file information, electronic seals, and electronic seal user authority information.

[0027] As an optional implementation, the trusted center's comparison process of the document and message digest includes: calculating the message digest of the electronic signature document information sent by the client device, and comparing it with the message digest of the electronic signature document information received from the electronic signature server; if they are consistent, symmetrically digitally signing the electronic signature document information.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention has fewer overall encryption times, which can reduce the computational complexity of the entire signing process.

[0030] The present invention establishes an electronic signature server, which manages the electronic seal information of the electronic signature user. The electronic signer first generates electronic signature file information through the electronic signature server, and the electronic signature file information is returned to the electronic signer, so that the electronic signer can check whether there are errors or problems in the electronic signature file.

[0031] The present invention sets up a trusted center, and configures the trusted center to receive the message digest of the electronic signature file sent by the electronic signature server, and at the same time receive the electronic signature file generated by the electronic signature server and sent by the electronic signer. By comparing the hash operation result of the latter with the former, it is guaranteed that the electronic signature file to be signed is a real electronic signature file processed by the electronic signature server, thereby ensuring the authenticity and reliability of the file.

[0032] The trusted center of the present invention is based on a symmetric key algorithm when signing, has anti-quantum attack characteristics, fundamentally eliminates the security defects of the traditional PKI-based electronic signature algorithm based on computational security, and has lower computational complexity; it can achieve unconditional security.

[0033] The calculation of the key-related message authentication code of the present invention realizes the message binding of the signed document, the electronic seal and the signer ID, and ensures the non-repudiation of the electronic signature message.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0036] Figure 1 This is a system structure diagram of Embodiment 1;

[0037] Figure 2 This is a schematic diagram of the process of Embodiment 2. DETAILED DESCRIPTION

[0038] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0039] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0041] Embodiment 1:

[0042] This embodiment provides an electronic signature system that is resistant to quantum attacks, relying on the rich symmetric key resources of the quantum cryptography network. Figure 1 shown.

[0043] The entire system includes a trusted center, an electronic signature server, and a signature applicant (terminal device). The functions of each component of the system are described in detail as follows:

[0044] The trusted center is a trusted third-party organization located at the quantum cryptography network terminal. The trusted center has a true random number signature key library (hereinafter referred to as the signature key library) for digital signature of electronic signature data. The keys in the key library are divided according to the length used for each digital signature, and the divided keys are numbered sequentially. The trusted center saves each key used for signature and its number until the signature validity period of the key expires. The trusted center can increase the number of signature keys in the key library according to the signature requirements.

[0045] The electronic signature server is set up in the quantum cryptography network terminal to store electronic seals, review the authority of applicants for signatures, generate signature information and send it to the trusted center for digital signature, and save the signature record of applicants for signatures. The electronic signature server registers with the trusted center. After the trusted center verifies its identity, it distributes a certain number of shared keys to it through the quantum cryptography network. The trusted center and the electronic signature server divide the shared keys according to the length of each key used and synchronize the sequence numbering. The trusted center and the electronic signature server safely store the shared keys. The shared keys are used for identity authentication when the electronic signature server communicates with the trusted center and for encrypted communication with the trusted center.

[0046] The electronic signature server stores electronic seal information including electronic seal file information, electronic seal users and authority information, which can be saved in the electronic signature server database.

[0047] The applicant for signature is a person who has electronic signature authority and can implement electronic signature on electronic documents through the electronic signature server. In the specific implementation process, it is implemented through a terminal device. In order to make it clearer to those skilled in the art, in this embodiment, the applicant for signature is used for description.

[0048] The applicant registers with the electronic signature server. After verifying his identity, the electronic signature server allows him to register, saves his registration information, and distributes a certain number of shared keys to him through the quantum cryptography network. The applicant and the electronic signature server divide the shared keys according to the length of the key used each time and synchronize the sequence numbering. The applicant and the electronic signature server securely save the shared keys respectively. The shared keys are used for identity authentication when the applicant and the electronic signature server communicate and for encrypted communication with the trusted center.

[0049] The applicant registers with the trusted center according to the same registration information (including registration ID) as the one registered with the electronic signature server and applies for the same registration ID. After verifying the identity, the trusted center allows the applicant to register, saves the registration information, and distributes a certain number of shared keys to the applicant through the quantum cryptography network. The applicant and the trusted center divide the shared keys according to the length of the key used each time and synchronize the sequence numbering. The applicant and the trusted center securely save the shared keys respectively. The shared keys are used for identity authentication when the applicant and the trusted center communicate and for encrypted communication with the trusted center.

[0050] The electronic signature process is divided into three parts: seal making, seal signing and seal verification.

[0051] The seal making process of this embodiment is completed with the assistance of the electronic signature server. The electronic signature server can be configured with an administrator to put the electronic seal information, the applicant information and the authority information to be used for the electronic signature into the database of the electronic signature server in advance.

[0052] Electronic seal information mainly includes the electronic seal ID and the electronic file information of the electronic seal. The signature personnel information mainly includes the ID of each electronic seal applicant with signature authority and the signature validity period of each ID. When the identity information of the applicant is confirmed and has signature authority, the electronic signature server packages the electronic seal information and the applicant information into electronic signature data, stamps it on the document that needs electronic signature, and generates electronic signature document information.

[0053] Embodiment 2:

[0054] Based on the system of embodiment 1, the following is provided: Figure 2 The signing process shown is detailed as follows:

[0055] The applicant uses the registration ID to initiate a signature application to the electronic signature server, and the electronic signature server and the applicant use a shared key for identity authentication.

[0056] The authentication process is as follows:

[0057] After receiving the signature application request, the electronic signature server sends a random number r1 to the applicant;

[0058] The applicant receives r1 and uses the unused shared key K with serial number n to calculate HMAC(r1||SID||n; K), where SID is the applicant ID and || indicates data concatenation operation.

[0059] The person applying for signature selects a random number r2, and sends r2, n and HMAC(r1||SID||n; K) to the electronic signature server;

[0060] The electronic signature server reads the shared key K with serial number n shared with the applicant, verifies the correctness of HMAC(r1||SID||n; K), and if correct, calculates HMAC(r1||r2||n; K) and sends it to the applicant;

[0061] The applicant verifies the correctness of HMAC(r1||r2||n; K). If it is correct, the identity authentication of both parties is successful, and both parties mark the shared key with serial number n as used.

[0062] After successful verification, the applicant for signature sends the ID of the electronic seal to be used for signature to the electronic signature server, and at the same time encrypts the electronic document that needs to be electronically signed using the shared key and sends it to the electronic signature server. The electronic signature server verifies the signature permission of the applicant for signature. If the permission is established, the electronic signature server decrypts the electronic document that needs to be electronically signed, packs the electronic seal information and the applicant's signature information into electronic signature data, and stamps it on the document to generate electronic signature document information.

[0063] The electronic signature server encrypts the electronic signature document information using the unused shared key between the electronic signature server and the applicant for signature, and at the same time uses the shared key to generate a key-related hash operation message authentication code for the ciphertext of the electronic signature document information, and sends the ciphertext and its message authentication code to the applicant for signature. The specific calculation method of the message authentication code is as follows:

[0064] HMAC(E(I, K n1 )||n1||n2; K n2 ),

[0065] where I is the electronic signature document information, I = I f ||I s ||SID(I f is the electronic document information that needs to be electronically signed, I s is the electronic seal information, SID is the ID of the electronic signer), K n1 and K n2 are the shared keys between the electronic signature server and the applicant for signature with serial numbers n1 and n2 respectively, E(I, K n1 ) represents the ciphertext generated by encrypting I using the key K n1 , HMAC(E(I, K n1 )||n1||n2; K n2 ) represents the key-related hash operation message authentication code of E(I, K n2 )||n1||n2 generated using the key K n1 . The electronic signature server sends E(I, K n1 ), n1, n2 and HMAC(E(I, K n1 )||n1||n2; K n2 ) to the applicant for signature.

[0066] The electronic signature server calculates the message digest of the electronic signature document information, calculates the key-related hash operation message authentication code of the message digest of the electronic signature document information using the unused shared key between the electronic signature server and the trusted center, and sends the message digest and its message authentication code to the trusted center. The calculation method of the message digest and its message authentication code is as follows:

[0067] Message digest MD = Hash(I), where I is the electronic signature document information;

[0068] Message authentication code MAC = HMAC(MD || SID; K n ), where K n is the shared key with sequence number n unused by the electronic signature server and the trusted center, and SID is the ID of the applicant for signature. The electronic signature server sends SID, MD, and MAC to the trusted center.

[0069] The applicant for signature receives the data E(I, K n1 ), n1, n2, and HMAC(E(I, K n1 ) || n1 || n2; K n2 ) sent by the electronic signature server. First, read the shared key K n2 shared by the applicant for signature with sequence number n2 and the electronic signature server. If K n2 has been used, the authentication fails and the data sent by the electronic signature server is rejected. Otherwise, use K n2 to verify the correctness of HMAC(E(I, K n1 ) || n1 || n2; K n2 ). If the verification is correct, mark the key K n2 as used, read the key K n1 with sequence number n1. If K n1 has been used, reject the ciphertext E(I, K n1 ). Otherwise, use K n1 to decrypt the ciphertext E(I, K n1 ) to obtain the electronic signature document information I, and mark K n1 as used.

[0070] The applicant for signature verifies the correctness of I. If I has an error, re-apply for an electronic signature from the electronic signature server. Otherwise, the applicant for signature encrypts the electronic signature document information using the shared key with the trusted center and calculates the hash operation message authentication code related to the key of the ciphertext of the electronic signature document information. The applicant for signature sends the ciphertext and its message authentication code to the trusted center. The calculation method of the message authentication code is as follows:

[0071] HMAC(E(I, K m1 ) || SID || m1 || m2; K m2 ),

[0072] where I is the electronic signature document information, I = I f || I s || SID(I f is the electronic document information that needs an electronic signature, I sis the electronic seal information, SID is the ID of the electronic signer), K n1 and K n2 are respectively the unused keys shared by the applicant signers with serial numbers m1 and m2 and the trusted center. E(I, K m1 ) represents the ciphertext generated by encrypting I with the key K m1 . HMAC(E(I, K m1 ) || SID || m1 || m2; K m2 ) represents the key-related hash operation message authentication code of E(I, K m2 ) || SID || m1 || m2 generated using the key K m1 . The applicant signer sends E(I, K m1 ), SID, m1, m2, and HMAC(E(I, K m1 ) || SID || m1 || m2; K m2 ) to the trusted center.

[0073] After the trusted center receives the message digest of the electronic signature document information and its message authentication code MD and MAC (HMAC(MD || SID; K n )) sent by the electronic signature server, it reads the key K n with serial number n shared by the applicant signer with ID SID and the trusted center. If K n has been used, it rejects the data sent by the electronic signature server. Otherwise, it uses K n to verify the correctness of MAC (HMAC(MD || SID; K n ). If it is correct, the trusted center temporarily saves the message digest MD of the electronic signature document information. Otherwise, it rejects the receipt and saving of MD.

[0074] After the trusted center receives the data E(I, K m1 ), SID, m1, m2, and HMAC(E(I, K m1 ) || SID || m1 || m2; K m2 ) sent by the applicant signer, it first reads the key K m2 with serial number m2 shared by the trusted center and the applicant signer with ID SID. If K m2 has been used, the authentication fails and it rejects the data sent by the applicant signer. Otherwise, it uses K m2 to verify the correctness of HMAC(E(I, K m1 ) || SID || m1 || m2; K m2 ). If the verification is correct, it marks the key K m2 as used, reads the key K m1 with serial number m1. If K m1has been used, then refuse to accept the ciphertext E(I, K m1 ), otherwise use K m1 Decrypted ciphertext E(I, K m1 ), obtain the electronic signature document information I, and K m1 The trusted center calculates the message digest of the electronic signature document information I and compares it with the MD sent by the electronic signature server. If they are inconsistent, the trusted center refuses to digitally sign the electronic signature document information I. Otherwise, the trusted center reads the unused key K with serial number SN in the signature key library. SN , using the key K SN Calculate the HMAC code of the electronic signature document information I as the symmetric key digital signature of the electronic signature document information. The calculation formula is as follows:

[0075] Ds=HMAC(I||T||SN,K SN ),

[0076] Where I is the electronic signature document information, T is the time, SN is the serial number of the signature key used, K SN is the key used for digital signature, and || represents data concatenation operation.

[0077] The trusted center encrypts I||T||Ds||SN as the electronic signature information of the document and sends it to the applicant, marking the encryption key as used. The applicant decrypts and obtains the electronic signature information of the document, and marks the decryption key as used.

[0078] The distribution of the above-mentioned shared keys can distribute multiple keys at a time according to the length of the shared keys used each time, and divide and synchronize the sequence numbering of the shared keys. When the shared keys are about to be used up, the two parties of the shared keys use the unused shared keys for identity authentication, use the quantum cryptography network to redistribute the shared keys, encrypt the newly distributed shared keys one by one with the same unused shared keys distributed last time, resynchronize the sequence numbering storage, and delete all the shared keys distributed last time. Using the old key to encrypt the new key facilitates the transfer of the identity information carried by the old key to the new encryption key.

[0079] Any recipient who has the electronic signature information of a document can encrypt it and send it to the trusted center to verify the legitimacy of the electronic signature. The trusted center extracts the key K with the serial number SN from the key library. SN , calculate HMAC(I||T||SN,K SN ), compare its value to see if it is equal to Ds, if so, the electronic signature is correct, otherwise it is incorrect.

[0080] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0081] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0082] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0083] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0085] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. An electronic signature method resistant to quantum attacks, characterized by: The following steps are involved: The electronic signature server obtains the signature application and authenticates the signature applicant; Receive the electronic seal ID information of the applicant who has passed the identity authentication and the encrypted document to be signed, review the authority of the applicant, generate electronic signature document information matching the authority, use the shared key with the applicant to generate the ciphertext and message authentication code of the electronic signature document information, and feedback the corresponding ciphertext and message authentication code to the applicant for decryption to obtain the document; Calculate the message digest of the electronic signature document information, use another shared key with a trusted center to calculate the authentication code of the message digest, and the trusted center is a third-party organization; submit the message digest and the authentication code to the third-party organization for verification, wait for the verification result of the third-party organization, and the third-party organization decrypts the ciphertext of the electronic signature document information sent by the applicant to obtain the electronic signature document information, calculate the message digest of the electronic signature document information, and compare the data with the message digest sent by the electronic signature server to obtain the comparison result. When both the verification result and the comparison result are passed, the applicant can obtain the electronic signature information after the third-party organization performs a symmetric key digital signature.

2. The method for electronic signature against quantum attack as claimed in claim 1, characterized in that: Obtain a signature application. Before authenticating the applicant, the applicant needs to undergo registration verification. After passing the verification, a shared key will be distributed to him / her for subsequent encrypted communications.

3. The electronic signature method resistant to quantum attack as claimed in claim 1 is characterized by: The specific process of the electronic signature server obtaining the signature application and authenticating the applicant includes: The electronic signature server sends a random number r1 to the person applying for signature; The message authentication code about the applicant's ID, random number r1, serial number n and shared key K calculated by the applicant using the unused shared key K with serial number n is received, and the serial number n and random number r2 are received; specifically, the applicant receives the random number r1, and uses the unused shared key K with serial number n to calculate HMAC(r1||SID||n; K), where SID is the applicant's ID, and || indicates data connection operation; the applicant selects the random number r2, and sends r2, n and HMAC(r1||SID||n; K) to the electronic signature server; Read the shared key K with serial number n shared with the applicant for signature, verify the correctness of the message authentication code, and if correct, calculate the message authentication code related to r1, r2, serial number n and key K, send it to the applicant for signature, and wait for the verification result. If the verification passes, mark the shared key with serial number n as used.

4. The electronic signature method resistant to quantum attack as claimed in claim 1, characterized in that: The process of generating electronic signature document information matching the authority includes: packaging the electronic seal information and the information of the person applying for signature into electronic signature data, stamping it on the document, and generating the electronic signature document information.

5. The electronic signature method resistant to quantum attack as claimed in claim 1 is characterized by: The specific process of a third-party agency performing symmetric key digital signature includes: using an unused key to calculate the message authentication code of the signature information as the symmetric key digital signature of the electronic signature document information, and the symmetric key digital signature contains information about the electronic signature document information, the time at that time, the serial number of the signature key used, and the key used for the digital signature.

6. The electronic signature method resistant to quantum attack as claimed in claim 1 is characterized by: The applicant, the electronic signature server and the trusted center respectively distribute multiple keys at a time according to the length of the shared key used each time, divide the shared keys and synchronize the sequence numbering; When the shared key is about to be used up, the two parties of the shared key use the unused shared key for identity authentication, redistribute the shared key using the quantum cryptography network, encrypt the newly distributed shared keys one by one using the same unused shared key distributed last time, resynchronize the sequential number storage, and delete all the shared keys distributed last time.

7. An electronic signature system resistant to quantum attacks, characterized by: include: The client device is configured to submit a signature application from a signatory, obtain the identity verification result of the signatory, authenticate the electronic signature server, send the electronic seal ID and encrypt and send the document to be signed, use the message authentication code to verify the identity of the electronic signature server, if it is correct, decrypt the electronic signature document information sent by it and verify the correctness, if it is correct, use the shared key with the trusted center to calculate the ciphertext and authentication code of the electronic signature document information, send them to the trusted center, and receive the encrypted electronic signature information; The electronic signature server is configured to verify the identity of the applicant, review the authority of the applicant, package the received applicant information and electronic seal information to generate electronic signature data, affix it to the document, generate electronic signature document information, send the ciphertext and authentication code of the electronic signature document information to the client device, and calculate the message digest of the electronic signature document information and its authentication code, and send them to the trusted center; The trusted center is configured to verify the identity of the electronic signature server using the authentication code of the electronic signature document information. If the verification is correct, the message digest is saved, and the electronic signature document information of the correct applicant is received, the message digest of the electronic signature document information is calculated, and compared with the stored message digest. If they are the same, the electronic signature document information is digitally signed with a symmetric key, the electronic signature information is generated, and it is encrypted and sent to the corresponding client device.

8. The electronic signature system resistant to quantum attacks as claimed in claim 7, characterized in that: The trusted center is a third-party organization located at the quantum cryptography network terminal and is provided with a true random number digital signature key library. The keys in the true random number digital signature key library are divided according to the length used for each digital signature and have different numbers.

9. The electronic signature system resistant to quantum attack as claimed in claim 7, characterized in that: The electronic signature server stores electronic seal file information, electronic seals and electronic seal user authority information.

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