TW201828642A - Method and device for realizing electronic signature, and signature server to solve the problem that the implementation cost of the U-shield signature scheme in the prior art is high - Google Patents

Abstract

The present invention provides a method and a device for realizing an electronic signature. The method incudes: determining a hash value of an electronic document to be signed; encrypting the hash value with a private key corresponding to a public key in the digital certificate; and merging the encrypted hash value, the digital certificate, and the picture of the electronic signature into the electronic document. With the technical scheme of the present invention, it is able to solve the problem that the implementation cost of the U-shield signature scheme in the prior art is high, so as to realize the mode of Internet signature and reduce the user cost.

Description

 Method, device and signature server for realizing electronic signature  

The present invention relates to the field of Internet technologies, and in particular, to a method, an apparatus, and a signature server for implementing an electronic signature.

When it is necessary to electronically sign a electronic file provided by a large Internet financial enterprise for a user, the private key used in the prior art by the electronic signature is placed in the U shield, when the user uses the electronic signature, Inserting the U shield into the computer, the electronic signature system signs the electronic document by obtaining the private key corresponding to the public key in the digital certificate in the U shield. The prerequisite for using the solution is that the user must purchase the U. Shield, so when a large number of users need an electronic signature, the implementation cost is high and the promotion is difficult.

In view of this, the present invention provides a new technical solution, which can solve the technical problem of instantly inventing an electronic signature of an electronic document in an Internet manner when the amount of users is large, and reducing the hardware cost of the electronic signature process.

In order to achieve the above object, the present invention provides a technical solution as follows: According to a first aspect of the present invention, a method for implementing an electronic signature is provided, comprising: determining a hash value of an electronic document to be signed; and using the hash value Encrypting the private key corresponding to the public key in the digital certificate; synthesizing the encrypted hash value, the digital certificate, and the picture of the electronic signature into the electronic document.

According to a second aspect of the present invention, a method for implementing an electronic signature is provided, comprising: determining a hash value of an electronic document to be signed; and transmitting the hash value and the second key of the electronic document to a second private network The second key is a preset key between the signature server and the third-party service platform; the second key pair is used in the third-party service platform. After the hash value is encrypted, the encrypted hash value is received via the second private network; the encrypted hash value, the digital certificate, and the electronic signature picture are synthesized into the electronic document in.

According to the collaborative manufacturer of the present invention, an apparatus for implementing an electronic signature is provided, comprising: a determining module for determining a hash value of an electronic document to be signed; and a first encryption module for determining the modulus The hash value determined by the group is encrypted by using a private key corresponding to the public key in the digital certificate; the signature synthesizing module is configured to encrypt the hash value and the identifier of the first encryption module. A digital certificate and a picture of the electronic signature are combined into the electronic document.

According to a fourth aspect of the present invention, a signature server is provided, comprising: a processor; a memory for storing the processor executable instructions; wherein the processor is configured to: determine a signature to be signed a hash value of the electronic document; encrypting the hash value with a private key corresponding to the public key in the digital certificate; and the encrypted hash value, the digital certificate, and the picture of the electronic signature Synthesized into the electronic document.

According to a fifth aspect of the present invention, a signature server is provided, comprising: a processor; a memory for storing the processor executable instructions; wherein the processor is configured to: determine a signature to be signed a hash value of the electronic document; sending the hash value and the second key of the electronic document to the third-party private network via the second private network, the second key being used by the signature server and the a preset key between the vendors' service platforms; after the third vendor's service platform encrypts the hash value by using the second key, receiving the encrypted hash by the second private network a value; the encrypted hash value, the digital certificate, and the electronic signature are synthesized into the electronic document.

It can be seen from the above technical solution that the present invention encrypts the hash value by using the private key corresponding to the public key in the digital certificate, and synthesizes the encrypted hash value, the digital certificate and the electronic signature image into the electronic document. Therefore, the problem of high implementation cost of the U-Shield signature scheme in the prior art is solved, the mode of the Internet signature is implemented, the user cost is reduced, the hash value is encrypted, and the encrypted hash value is The digital voucher is synthesized into an electronic document, which enhances the security and credibility of the electronic signature.

21‧‧‧ Third Party Certification Center

22‧‧‧Signature Server

23‧‧‧Cloud database

24‧‧‧First Business Platform

31‧‧‧Signature Server

32‧‧‧ Third Party Certification Center

41‧‧‧Signature Server

42‧‧‧ Third Party Service Platform

61‧‧‧Determining modules

62‧‧‧First encryption module

63‧‧‧Signature Synthesis Module

64‧‧‧Second encryption module

65‧‧‧Storage module

66‧‧‧Signature Synthetic Module

67‧‧‧ receiving module

621‧‧‧Acquisition unit

622‧‧‧Decryption unit

623‧‧‧Encryption unit

624‧‧‧First sending unit

625‧‧‧First receiving unit

1A is a flow chart showing a method of implementing an electronic signature according to an exemplary embodiment of the present invention; FIG. 1B is a schematic diagram showing a picture of an electronic signature according to an exemplary embodiment of the present invention; A schematic diagram of a digital certificate in accordance with an exemplary embodiment of the present invention is shown; FIG. 2A shows a flow diagram of a method of implementing an electronic signature in accordance with another exemplary embodiment of the present invention; FIG. 2B illustrates A scene view of another exemplary embodiment of the present invention; FIG. 3A shows a schematic flowchart of a method of implementing an electronic signature according to still another exemplary embodiment of the present invention; FIG. 3B illustrates yet another A scenario diagram of an exemplary embodiment; FIG. 4A illustrates a flow diagram of a method of implementing an electronic signature in accordance with yet another exemplary embodiment of the present invention; FIG. 4B illustrates a further exemplary embodiment in accordance with the present invention. FIG. 5 is a schematic structural diagram of a signature server according to an exemplary embodiment of the present invention; FIG. 6 is a schematic diagram showing the structure of an electronic signature device according to an exemplary embodiment of the present invention. ; FIG. 7 shows a schematic structural diagram of another exemplary embodiment of the present invention is implemented in accordance with an electronic signature device.

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. The following description refers to the same or similar elements in the different figures unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with aspects of the invention as detailed in the appended claims.

The terminology used in the present invention is for the purpose of describing particular embodiments, and is not intended to limit the invention. The singular forms "a", "the" and "the" It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information may also be referred to as second information without departing from the scope of the invention. Similarly, the second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "when" or "in response to a determination."

In order to further illustrate the present invention, the following embodiments are provided: According to one embodiment of the present invention, an encrypted hash value, a digit, is encrypted by using a private key corresponding to the public key in the digital certificate for the hash value. The images of the voucher and the electronic signature are synthesized into an electronic document, thereby solving the problem of high implementation cost of the U-Shield signature scheme in the prior art, realizing the mode of the Internet signature, reducing the user cost, by The hash value encryption and the integration of the encrypted hash value and digital certificate into the electronic document enhance the security and credibility of the electronic signature.

1A is a flow chart showing a method of implementing an electronic signature according to an exemplary embodiment of the present invention, and FIG. 1B is a schematic diagram showing an electronic signature according to an exemplary embodiment of the present invention, and FIG. 1C shows A schematic diagram of a digital certificate in accordance with an exemplary embodiment of the present invention; applicable to a signature server. As shown in FIG. 1A, the method for implementing an electronic signature includes the following steps: Step 101, determining a hash value of an electronic document to be signed; and Step 102, using a private key corresponding to the public key in the digital certificate for the hash value. The key is encrypted; in step 103, the encrypted hash value, the digital certificate, and the electronic signature image are synthesized into an electronic document.

In step 101, in an embodiment, the electronic document may be a local file (eg, a certification file, an electronic receipt, etc.); in another embodiment, the electronic document may be from a first service platform, and the first service platform may For a payment-type financial service platform (for example, Alipay), correspondingly, the electronic document may be an asset certificate, a bill, or an electronic receipt; in another embodiment, the electronic document may be from a second service platform, and the second service platform may be For a deposit-type financial business platform (for example, Treasures), correspondingly, the electronic document can be proof of loan and interest; in another embodiment, the electronic document can be from the third service platform, and the third service platform can be the Internet. The financial service platform (for example, the network merchant bank), correspondingly, the electronic document can be an electronic certificate invented by the terminal user, etc., and thus, the present invention does not limit the source of the electronic document.

In an embodiment, the electronic signature may be an electronic signature of the enterprise corresponding to the first service platform, an electronic signature of the enterprise corresponding to the second service platform, and an electronic signature of the enterprise corresponding to the third service platform. In an embodiment, the hash value of the electronic document can be extracted by a hash algorithm.

In step 102, in an embodiment, the encryption method for the hash value may be determined according to the source of the electronic document. For example, if the electronic document is from the first service platform, the encryption machine may be set in the signature server by encrypting. The first key of the machine (also known as the primary key, MainKey) to encrypt the private key in the digital certificate; for example, if the electronic document is from the second service platform, the hash value can be sent to the third private network. The vendor certification authority (for example, the CA center) encrypts the hash value by the third-party network by using the private key corresponding to the public key in the digital certificate, and then encrypts the hash by the first private network. The value is returned to the signature server; for example, if the electronic document is from the third service platform, the second key set between the hash value, the signature server, and the third party financial platform can be sent to the second private network. The encryption machine of the three service platforms, the third service platform encrypts the hash value by using the second key set by both parties by the encryption machine, and then the third industry Hash value is returned to the signature server platform then encrypted. The hash value can be encrypted by using different encryption methods for electronic documents from different sources to meet personalized business needs.

In step 103, in an embodiment, the corresponding electronic signature image can be obtained from the corresponding service platform (the first service platform, the second service platform, and the third service platform), and the encrypted hash value and digit are obtained. For the synthesis of the picture of the voucher and the electronic signature into the electronic document, refer to the related description of the prior art, which will not be described in detail herein.

As shown in FIG. 1B, the electronic signature synthesized on the electronic document is “AB Company”, and when the click event on the electronic signature of “AB Company” is monitored, the related information of the digital certificate shown in FIG. 1C is displayed. Since the digital certificate is obtained through the third-party certification center, the user can verify the authenticity of the electronic signature by using a digital certificate.

It can be seen from the above description that the embodiment of the present invention implements the mode of the Internet signature by the steps S101-S103, and solves the problem of high implementation cost of the U shield signature scheme in the prior art, and reduces the user cost by using The hash value encryption and the integration of the encrypted hash value and digital certificate into the electronic document enhance the security and credibility of the electronic signature.

2A shows a flow diagram of a method of implementing an electronic signature in accordance with another exemplary embodiment of the present invention, and FIG. 2B illustrates a scenario of a method of implementing an electronic signature in accordance with another exemplary embodiment of the present invention. The embodiment is exemplified by taking an electronic document from the first service platform as an example. As shown in FIG. 2A, the method for implementing an electronic signature includes the following steps: Step 201, determining a hash value of an electronic document to be signed; Step 202, acquiring a digital certificate and a private key corresponding to the public key in the digital certificate, The private key is encrypted; in step 203, the encrypted private key is decrypted; in step 204, the decrypted private key is used to encrypt the hash value; in step 205, the encrypted hash value and the digital certificate are encrypted. The images of the electronic signature are combined into an electronic document.

For the description of the foregoing step 201, refer to the related description of the foregoing step 101, which will not be described in detail herein.

In step 202 to step 204, in an embodiment, the digital certificate and the encrypted private key may be obtained from the cloud database, wherein the first key of the encryption machine on the signature server may be used (also The primary key is encrypted by encrypting the private key corresponding to the public key in the digital certificate, and then stored in the cloud database, and decrypting the encrypted private key stored in the cloud database when needed. . In another embodiment, the cloud database can store a large number of digital certificates and a private key corresponding to the public key in the digital certificate, thereby implementing a large number of digital certificates and corresponding to the public key in the digital certificate. The security of the private key is stored.

For the description of the foregoing step 205, refer to the related description of the foregoing step 103, and details are not described herein.

As an exemplary scenario, as shown in FIG. 2B, the signature server 22 invents a digital certificate from the third vendor certification center 21, by means of the first key of the local encryption machine (not shown) of the signature server 22. The private key corresponding to the public key in the digital certificate is encrypted, and the encrypted private key and digital certificate are stored in the cloud database 23. The signature server 22 obtains the electronic document that needs to be electronically signed from the first service platform 24, extracts the hash value of the electronic document by using the hash algorithm, and acquires the digital certificate and the encrypted private key from the cloud database 23, The hash value is transmitted to the encryption machine local to the signature server 22, and the private key corresponding to the public key in the digital certificate is decrypted in the encryption machine local to the signature server 22, and obtained in the digital certificate. The public key corresponding to the public key, the encryption machine encrypts the hash value by using the private key. Finally, the signature server 22 synthesizes the encrypted hash value, digital certificate and electronic signature onto the electronic document. In turn, an electronic document can be provided to the user. Since the private key corresponding to the public key in the digital certificate is decrypted by the first key, and the hash key is encrypted by the private key corresponding to the digital certificate public key, the signature servo is used in the signature servo. The internal processing of the encryptor of the device ensures that the private key corresponding to the public key in the digital certificate is secure during use.

In this embodiment, since the digital certificate and the encrypted private key are stored in the cloud database, when the electronic document needs to be electronically signed, the encrypted private key of the digital certificate and the digital certificate is obtained from the cloud database. In the prior art, the encryption machine in the third-party certification center can only save a limited number of private keys corresponding to the public key in the digital certificate, thereby supporting the large amount of data and high concurrency of the Internet signature. The characteristics and ensure the security of the private key corresponding to the public key in the digital certificate.

FIG. 3A illustrates a flow diagram of a method of implementing an electronic signature in accordance with yet another exemplary embodiment of the present invention, and FIG. 3B illustrates a scenario of a method of implementing an electronic signature in accordance with yet another exemplary embodiment of the present invention. FIG. 1 is an exemplary illustration of an electronic document provided by a second service platform. As shown in FIG. 3A, the method for implementing an electronic signature includes the following steps: Step 301: determining a hash value of an electronic document to be signed; and step 302, transmitting a hash value of the electronic document to a third party through a first private network. a center, wherein the third-party certification center is configured to generate the digital certificate and encrypt the hash value by using a private key corresponding to the public key in the digital certificate; and step 303, receiving the encryption from the third-party private network through the first private network After the hash value; step 304, the encrypted hash value, the digital certificate and the electronic signature picture are synthesized into the electronic document.

For the description of the foregoing step 301, refer to the related description of step 101 above, and details are not described herein.

In step 302 and step 303, in an embodiment, the first private network may be a dedicated communication network connected to the signature server and the authentication center, and no other devices are connected in the dedicated communication network. The first private network transmits the hash value and the encrypted hash value to ensure the security of the hash value.

For the description of the foregoing step 304, refer to the related description of the foregoing step 103, which is not detailed here.

As an exemplary scenario, as shown in FIG. 3B, the signature server 31 is co-signed with the third-party certification authority 32. In the joint signature process, the signature server 31 extracts the hash value of the electronic document by the hash algorithm, and the signature server 31 sends the hash value to the third party certification center 32 via the first private network, which is authenticated by the third party. The center 32 encrypts the hash value using the private key corresponding to the public key in the digital certificate, and then returns the encrypted hash value to the signature server 31 via the first private network, and the signature server 31 The encrypted hash value, digital certificate, and electronic signature are combined into an electronic document, and the electronic document can be provided to the user.

In this embodiment, the hash value of the electronic document is sent to the third-party private network to the third-party private network, and the hash value is encrypted in the third-party authentication center by the private key corresponding to the public key in the digital certificate. After receiving the encrypted hash value through the first private network, the encrypted hash value, the digital certificate and the electronic signature image are synthesized into the electronic document, which solves the high implementation cost of the U shield signature scheme in the prior art. The problem is that the user cost is reduced, and the hash value is encrypted by using the private key corresponding to the public key stored in the digital certificate of the third-party certificate authority, and then the digital certificate and the encrypted hash value are synthesized into On the electronic document, the credibility of the electronic signature is enhanced, and at the same time, the electronic document can be leaked to other unrelated businesses to ensure the commercial security of the electronic document.

4A shows a flow diagram of a method of implementing an electronic signature in accordance with yet another exemplary embodiment of the present invention, and FIG. 4B illustrates a scenario of a method of implementing an electronic signature in accordance with yet another exemplary embodiment of the present invention. FIG. 1 is an exemplary embodiment of an electronic document provided from a third service platform. As shown in FIG. 4A, the method for implementing an electronic signature includes the following steps: Step 401: determining a hash value of an electronic document to be signed; and step 402, sending a hash value of the electronic document and a second key through a second private network. To the third-party service platform, where the second key is a preset key or a mutually negotiated key between the signature server and the third-party service platform; and step 403, receiving the encrypted hash value via the second private network; Step 404, synthesizing the encrypted hash value, the digital certificate and the electronic signature into an electronic document.

For the description of the above step 401, refer to the related description of the above step 101, which will not be described in detail herein.

In step 402 and step 403, in an embodiment, the second private network may be a dedicated communication network connected to the signature server and the third-party service platform, and no other device is connected to the dedicated communication network. The hash value and the encrypted hash value are transmitted via the second private network to ensure the security of the hash value. In an embodiment, the third-party service platform may be a platform that can provide electronic documents, such as the first service platform, the second service platform, and the third service platform, in the foregoing embodiments.

For the description of the above step 404, refer to the related description of the above step 103, which will not be described in detail herein.

As an exemplary scenario, as shown in FIG. 4B, the signature server 41 acquires an electronic document from the third-party service platform 42, extracts the hash value of the electronic document using a hash algorithm, and transmits the hash value to the encryption of the third-party service platform 42. The encryption machine of the third party service platform 42 encrypts the hash value by the second key, and then the third service platform 42 returns the encrypted hash value to the signature server 41, and the signature server 41 encrypts. The subsequent hash value, digital certificate, and electronic signature are combined into an electronic document, and the electronic document can be provided to the user.

This embodiment can meet the requirement that the third-party service platform 42 requires the private key corresponding to the public key in the digital certificate to be stored, and the flexibility of the electronic signature mode is improved.

With the above embodiments, different electronic signature signature schemes can be used in different service scenarios, so that the personalized service requirements are satisfied when the advantages of various electronic signature usage schemes are exerted.

Corresponding to the above-described method of implementing an electronic signature, the present invention also proposes a schematic configuration diagram of the signature server according to an exemplary embodiment of the present invention shown in FIG. 5. Referring to FIG. 5, on the hardware side, the network server includes a processor, an internal bus, a network interface, a memory, and non-volatile memory, and may of course include hardware required for other services. The processor reads the corresponding computer program from the non-volatile memory into the memory and then operates to form a device for implementing the electronic signature on the logical level. Of course, the present invention does not exclude other implementations, such as a logic device or a combination of software and hardware, etc., that is, the execution body of the following processing flow is not limited to each logical unit, and may also be used. It is a hardware or logic device.

FIG. 6 is a schematic structural diagram of an apparatus for implementing an electronic signature according to an exemplary embodiment of the present invention; as shown in FIG. 6, the apparatus for implementing an electronic signature may include: a determining module 61 and a first encryption module 62. , signature synthesis module 63. The determining module 61 is configured to determine a hash value of the electronic document to be signed; the first encryption module 62 is configured to use the public key corresponding to the digital certificate in the hash value determined by the determining module 61. The private key is encrypted; the signature synthesizing module 63 is configured to synthesize the hash value, the digital certificate and the electronic signature image encrypted by the first encryption module 62 into the electronic document.

FIG. 7 is a schematic structural diagram of an apparatus for implementing an electronic signature according to an exemplary embodiment of the present invention; as shown in FIG. 7, the first encryption module 62 may include: The obtaining unit 621 is configured to obtain a digital certificate and a private key corresponding to the public key in the digital certificate, the private key is encrypted; and the decrypting unit 622 is configured to encrypt the obtained unit 621. The private key is decrypted; the encryption unit 623 is configured to encrypt the hash value by using the secret key decrypted by the decryption unit 622.

In an embodiment, the apparatus may further include: a second encryption module 64, configured to encrypt the private key corresponding to the public key in the digital certificate by using the first key; the storage module 65, configured to: The private key and the digital certificate encrypted by the second encryption module 64 are stored.

In one embodiment, the digital credentials and the encrypted private key are obtained from the cloud repository.

In an embodiment, the first encryption module 62 may include: a first sending unit 624, configured to send the hash value of the electronic document to the third-party private network via the first private network, where the third-party authentication center is used by the third-party authentication center. The digital certificate is generated and the hash value is encrypted by using a private key corresponding to the public key in the digital certificate; the first receiving unit 625 is configured to receive the encrypted hash value from the third-party private network via the first private network.

In one embodiment, the first private network is a dedicated communication network that is connected to the Signature Server and the third-party certification authority.

In an embodiment, the device may further include: a sending module 66, configured to send the hash value and the second key of the electronic document to the third-party private network to the third-party private network, where the second key is the signature server. The preset key between the device and the third-party service platform; the receiving module 67 is configured to receive the encrypted hash value from the third-party private network through the second private network.

The above embodiments can be seen that different electronic signatures can be applied in different service scenarios. Therefore, when the advantages of various electronic signatures are utilized, the personalized service requirements are met.

Other embodiments of the invention will be apparent to those skilled in the <RTIgt; The present invention is intended to cover any variations, uses, or adaptations of the present invention, which are in accordance with the general principles of the invention and include common general knowledge or common technical means in the art that are not disclosed in the present invention. . The specification and examples are to be regarded as illustrative only, and the true scope and spirit of the invention

It is also to be understood that the terms "comprises" or "comprising" or "comprising" or any other variations are intended to encompass a non-exclusive inclusion, such that a process, method, article, Other elements not explicitly listed, or elements that are inherent to such a process, method, commodity, or equipment. An element defined by the phrase "comprising a ..." does not exclude the presence of additional equivalent elements in the process, method, item, or device including the element.

The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalents, improvements, etc., which are made within the spirit and principles of the present invention, should be included in the present invention. Within the scope of protection.

Claims (18)

 A method for implementing an electronic signature, characterized in that it is applied to a signature server, the method comprising: determining a hash value of an electronic document to be signed; and using the public key in the digital certificate for the hash value The corresponding private key is encrypted; the encrypted hash value, the digital certificate and the electronic signature picture are synthesized into the electronic document.    The method of claim 1, wherein the encrypting the hash value with a private key corresponding to a public key in the digital certificate comprises: acquiring a digital certificate and the digital certificate The private key corresponding to the public key, the private key is encrypted; the encrypted private key is decrypted; and the hash value is encrypted by using the decrypted private key.    The method of claim 2, wherein the method further comprises: encrypting the private key by a first key; storing the digital certificate and the encrypted private key.    The method of claim 2, wherein the digital voucher and the encrypted private key are obtained from a cloud repository.    The method of claim 1, wherein the encrypting the hash value with a private key corresponding to a public key in the digital certificate comprises: placing the hash of the electronic document The value is sent to the third-party private network via the first private network, wherein the third-party certificate authority is configured to generate the digital certificate and adopt a private key pair corresponding to the public key in the digital certificate The hash value is encrypted; the hash value encrypted from the third vendor authentication center is received via the first private network.    The method of claim 5, wherein the first private network is a dedicated communication network connected to the signature server and the third-party certification authority.    A method for implementing an electronic signature, characterized in that it is applied to a signature server, the method comprising: determining a hash value of an electronic document to be signed; and using the hash value and the second key of the electronic document Transmitting to the third-party private network to the third-party service platform, where the second key is a preset key between the signature server and the third-party service platform; After the second key encrypts the hash value, receiving the encrypted hash value via the second private network; synthesizing the encrypted hash value, the digital certificate, and the electronic signature picture into the electronic In the documentation.    The method of claim 9, wherein the second private network is a dedicated communication network connected to the signature server and the third service platform.    An apparatus for implementing an electronic signature, the apparatus comprising: a determining module, configured to determine a hash value of an electronic document to be signed; and a first encryption module, configured to determine the determining module The hash value is encrypted by using a private key corresponding to the public key in the digital certificate; the signature synthesis module is configured to encrypt the hash value and the digital certificate after the first encryption module is encrypted. And a picture of the electronic signature is synthesized into the electronic document.    The device of claim 9, wherein the first encryption module comprises: an obtaining unit, configured to acquire a digital certificate and a private key corresponding to the public key in the digital certificate, The private key is encrypted; a decryption unit is configured to decrypt the encrypted private key acquired by the obtaining unit; and an encryption unit is configured to use the private key decrypted by the decryption unit The hash value is encrypted.    The device of claim 10, wherein the device further comprises: a second encryption module, configured to, by the first key pair, a private key corresponding to the public key in the digital certificate Encrypting; storing a module for storing the digital certificate and a private key corresponding to the public key in the digital certificate.    The device of claim 10, wherein the digital voucher and the encrypted private key are obtained from a cloud repository.    The device of claim 9, wherein the first encryption module comprises: a first sending unit, configured to send the hash value of the electronic document to the a third-party authentication center, wherein the third-party certificate authority is configured to generate the digital certificate and encrypt the hash value by using a private key corresponding to the public key in the digital certificate; the first receiving unit, And the receiving, by the first private network, the hash value after being encrypted from the third-party authentication center.    The device of claim 13, wherein the first private network is a dedicated communication network connected to the signature server and the third-party certification authority.    The device of claim 9, wherein the device further comprises: a transmitting module, configured to send the hash value and the second key of the electronic document to the a third service platform, where the second key is a preset key between the signature server and the third-party service platform; and the receiving module is configured to receive the cooperation from the second private network. The hash value after the vendor certificate authority encrypts.    The device of claim 15, wherein the second private network is a dedicated communication network connected to the signature server and the third service platform.    A signature server, wherein the signature server comprises: a processor; a memory for storing processor executable instructions; wherein the processor is configured to: determine an electronic document to be signed a hash value; encrypting the hash value with a private key corresponding to the public key in the digital certificate; synthesizing the encrypted hash value, the digital certificate, and the electronic signature picture into the In the electronic document.    A signature server, wherein the signature server comprises: a processor; a memory for storing processor executable instructions; wherein the processor is configured to: determine an electronic document to be signed a hash value, the hash value of the electronic document, and the second key are sent to the third-party private network via the second private network, where the second key is used by the signature server and the third-party manufacturer a preset key between the service platforms; after the third vendor key encrypts the hash value by using the second secret key, the encrypted hash value is received by the second private network; The encrypted hash value, digital voucher, and electronic signature picture are synthesized into the electronic document.