CN1722656B - A digital signature method and digital signature tool - Google Patents

Abstract

The invention discloses a digital signature method and a signature tool, comprising the following steps: dividing a file to be signed into a plurality of data packets, then sending the data packets into signing hardware in batches, encrypting the mixed data by two private keys in the hardware respectively, and then outputting the encrypted data to software respectively; after the software receives the two groups of encrypted data, the data are reorganized into a new signature file; the signature file comprises two parts, wherein one part is a ciphertext encrypted by a private key to an original text, and the other part is a ciphertext encrypted by the private key to the original text; the invention has the following advantages: the signed digital file can be clearly known by anyone with legal authority about the content, identity, source, author and the final signature time of the file; any signed digital file is unique, i.e., none of the signed files are the same; any modifications made to the signed digital file are known.

Description

A digital signature method and digital signature tool

technical field

The invention relates to digital signature technology, in particular to a digital signature method, and also relates to a digital signature tool using the method.

Background technique

With the continuous advancement of science and technology, with the continuous popularization of computers and the Internet, more and more handwritten documents are replaced by digital documents, so how to determine the identity, legal source, author and final signature of a digital document what time? How to ensure that digital files are unique once they are signed? How to ensure that any modification made to a signed digital file is known? There is an urgent need for a tool and a method to realize the above functions. At the same time, we also need to make the digital document after being signed by anyone with legal authority to clearly know the content, identity, source, author, and last signature time of the signed document. A key here is the last signature time of the document and the identity of the author. The last signature time of the document and the identity of the author can ensure that each signed document is unique.

Contents of the invention

A main purpose of the present invention is to provide a digital signature method, which can make:

1. The signed digital file can be clearly known by anyone with legal authority to the content, identity, source, author, and last signature time of the signed file.

2. Any signed digital file is unique, that is, no signed file is the same.

3. Any modification made to the signed digital file is known.

Another object of the present invention is to provide a digital signature tool using the above-mentioned signature method, which can realize the functions of the above-mentioned digital signature method.

The digital signature method provided by the present invention is as follows:

Signature steps:

Generate signature file: The software divides the file to be signed into multiple data packets, and then sends these data packets to the signing hardware in batches, and then sends out encryption instructions. The hardware first mixes the input data with the hardware ID and the current time according to certain rules, then uses two private keys inside the hardware to encrypt the mixed data, and then outputs them to the software respectively, and the software receives the two sets of encryption After the data, reorganize the data into a new signature file. The signature file contains two parts, one part is the ciphertext encrypted by the private key pair of the original text, and the other part is the ciphertext encrypted by the private key pair of the original text. In this way, the newly generated signature file has uniqueness based on hardware identity and time on the basis of the original text, and also has encryption features.

Verify signature steps:

1. Use your own key for authentication:

The software sends the part of the file to be signed encrypted by the private key to the hardware, and then issues a decryption command, requiring the hardware to use its own private key to decrypt it. The hardware will use the private key to decrypt the incoming data, and then return the decrypted data to the software. Then, the software sends the part of the file to be signed encrypted by the private key 2 into the hardware, and then sends a decryption command, requiring the hardware to decrypt it with its own private key 2. The hardware will use the private key 2 to decrypt the input data, and then return the decrypted data to the software.

The software compares the two decrypted results before and after. If they are not the same, it means that the file has been modified. At this time, an error can be prompted and the different places will be displayed. If they are the same, it means that the signed file has not been modified. Since the decrypted data contains the ID of the hardware, the time of signing and the original original content, the software can separate these data and generate the signature. An original copy of a document, showing who signed it and when it was signed.

2. Use the encryption key output by the signing hardware to verify on any signing tool (excluding itself):

When verifying the signature file, the signature tool that generates the signature file must output its encrypted private key after generating the signature file (use the public key to encrypt the two private keys in the hardware, and then output).

The software first obtains the encrypted private key of the signature tool (referred to as the original signature tool) of the signature file, and then sends the encrypted private key to the signature tool to be verified (referred to as the verification tool for short), and the verification tool uses the public The key decrypts the input encryption key and generates two private keys of the original signature tool, so that the verification tool can use the private key of the original signature tool to verify the files signed by the original signature tool. The verification method Same as above, not repeated here.

3. Use the key encrypted by the random number output by the signing hardware to verify on the designated signing tool:

The biggest difference between this verification method and the previous verification method is that no authorized signature tool can verify it, which increases the security of the signed file, and will not cause any damage due to the theft of the output encryption key. Signed documents are viewed by unauthorized persons.

1. The authorized signature tool (referred to as the authorized tool) first generates a random number, then mixes the random number with its own ID according to certain rules, then encrypts it with a public key, and then encrypts the encrypted data output.

2. The software sends the output encrypted data to the original signature tool, and the original signature tool uses the public key to decrypt the data, restores it to a random number and the authorized tool ID, and then uses the random number to encrypt the data in the original signature tool. The private key is encrypted, and then the encrypted private key and the authorized tool ID are output. When the software obtains the encrypted private key, the authorized tool ID is displayed to the user to verify its identity.

3. The software sends the encrypted key encrypted by the random number to the authorized tool, and the authorized tool uses the random number generated by it to decrypt the encrypted key and generates two private keys of the original signature tool. In this way, the verification tool is You can use the private key of the original signature tool to verify the files signed by the original signature tool, and the verification method is the same as above.

A digital signature tool adopting the above-mentioned digital signature method is provided, comprising a tool box body, a single-chip microcomputer arranged in the box body, and the following units for exchanging information with the single-chip microcomputer are also arranged in the box body: a hardware encryption algorithm unit and a decryption algorithm unit, a unique ID number generation unit, at least one public key unit, at least two private keys, a random number generator unit, a random number storage area unit, a clock counter unit, and the box body is also provided with peripheral equipment Peripheral interface and long-term power supply for communication.

The signature tool provided by the present invention has the following advantages:

1. It is non-replicable, that is, the hardware cannot be completely copied (except for the issuing agency), so that the uniqueness of the hardware is guaranteed at the hardware level.

Second, the hardware is a black box, which can be composed of devices like smart cards or single-chip microcomputers.

3. The hardware can have built-in hardware encryption and decryption algorithms, or use software encryption and decryption algorithms.

4. There is a unique ID number in the hardware, which is used as the identity certificate of the hardware.

5. There are one or more public keys in the hardware.

6. There are two or more private keys in the hardware

7. The hardware has a peripheral interface that can communicate with peripheral devices.

8. The hardware has a long-term power supply system (such as battery power supply) and a backup power supply system, and can have a power indicator device.

9. The clock in the hardware cannot be modified or set (except the issuing institution), and the clock has been set by the issuing institution to synchronize with the international time when it leaves the factory.

10. Once the hardware is powered off, it will fail immediately, that is, it cannot be operated in any way, even if it is powered on again, it cannot be operated, thus ensuring that the hardware clock cannot be illegally modified.

11. There is a random number generator inside the hardware for generating random numbers.

12. There is a random number storage area inside the hardware, which is used to store some recently generated random numbers.

The hardware internal system also has the following functions:

When the encrypted data command is issued externally, firstly, the current hardware clock and hardware ID are mixed with the input data to be encrypted according to certain rules to generate a new set of encrypted data, and then use the hardware built-in private key 1 and the private The second key encrypts the newly generated mixed data respectively, generates two different encrypted data, and then outputs them to the peripheral device. An example is as follows: Suppose the encrypted data group is 128 bits, and the data to be encrypted is 0×01, 0×02, 0×03, 0×04, 0×05, 0×06, 0×07, 0×08, hardware The internal system first sets the system clock (the number of milliseconds elapsed relative to a certain fixed time): assumed to be 0×45, 0×67, 0×89, 0×10, and the unique ID inside the hardware: assumed to be 0×01, 0× 02, 0×03, 0×04 to form a 128-bit group, and then use the private key one pkey1 and the private key two pkey2 to encrypt the data in the group to generate two sets of encrypted data, so that the two sets After the encrypted data are correctly decrypted, they all include the hardware ID and the time when the visa was issued.

1. When the encryption pkey1 and pkey2 key commands are issued from the outside, the internal system of the hardware uses the public key ckey1 to encrypt pkey1 and pkey2 respectively and then output them to the peripheral system.

2. When an external command is issued to require the hardware to output a random number, the internal system of the hardware uses the public key ckey1 to encrypt the generated random number and output it.

3. When the command to encrypt pkey1 and pkey2 with random data is issued externally, the hardware internal system uses the public key ckey1 to encrypt pkey1 and pkey2 respectively to generate a set of encrypted data, and then use the input random data to encrypt the generated data The data is encrypted and then output to the peripheral system.

4. When an external request is issued to decrypt data using its own key, the hardware system uses private key one pkey1 and private key two pkey2 to decrypt the input two groups of group data, and then compares the two groups of decrypted data and output.

5. When an external request is issued to use the input encryption key to decrypt data, the hardware internal system first uses the public key to decrypt the input encrypted private key 1 and private key 2, and then uses the two private keys to decrypt the data. The input two sets of block encrypted data are decrypted, and then the two sets of decrypted data are compared and output.

6. When an external request is sent to decrypt the data using the random data in the hardware and the input encryption key, the internal system of the hardware first uses the public key in the hardware to decrypt the encrypted random key input, and then uses the random data Decrypt the input encryption key, and then use the public key to decrypt the input encrypted private key 1 and private key 2, and then use the two private keys to decrypt the input two groups of encrypted data , and then compare and output the two sets of decrypted data.

7. When the outside requires the hardware to output its own ID, the internal system of the hardware outputs its own ID to the peripheral system.

9. In order to prevent the signature from being misused by others if the signature tool is lost or stolen, when using the signature tool, the hardware requires the input of a password for verification or other verification to work.

In addition to the hardware, there is also a software for manipulating the hardware. The software must implement the following functions:

1. Issue a command to require the hardware to encrypt the input data, and then process the two sets of output data.

2. Issue a command to require the hardware to encrypt the private key in the hardware, and then process the output data.

3. Issue a command to request the hardware to output the encrypted random key.

4. Issue a command to request the hardware to encrypt the pkey1 and pkey2 keys with random data, and then process the output data.

5. Issue a command to request the hardware to use its own key to decrypt the data, and then process the output two sets of data.

6. Issue a command to use the input encryption key to decrypt the data, and then process the output two sets of data.

7. Issue a command to decrypt the data using the random data in the hardware and the input encryption key, and then process the two sets of output data.

8. Read out the unique ID inside the hardware.

Description of drawings

Fig. 1 is the composition block diagram of digital signature tool of the present invention;

Fig. 2 is a schematic circuit diagram of a digital signature tool;

Fig. 3 is a block diagram of the workflow of the digital signature method of the present invention.

Detailed ways

The structure of the digital signature tool is shown in Figure 1 and Figure 2. There is a single-chip microcomputer in the tool box, and the following units for exchanging information with the single-chip microcomputer are also set in the box: hardware encryption algorithm unit and decryption algorithm unit, unique ID Number generation unit, one or more public key units, two or more private keys, random number generator unit, random number storage area unit, clock counter unit, there are also devices on the box for communicating with peripheral equipment Communication peripheral interface and long-term power supply device.

Further illustrate the working principle of the digital signature method of the present invention below in conjunction with Fig. 3:

Signature process:

Generate signature file: The software divides the file to be signed into multiple data packets, and then sends these data packets to the signing hardware in batches, and then sends out encryption instructions. The hardware first mixes the input data with the hardware ID and the current time according to certain rules, then uses two private keys inside the hardware to encrypt the mixed data, and then outputs them to the software respectively, and the software receives the two sets of encryption After the data, reorganize the data into a new signature file. The signature file contains two parts, one part is the ciphertext encrypted by the private key pair of the original text, and the other part is the ciphertext encrypted by the private key pair of the original text. In this way, the newly generated signature file has uniqueness based on hardware identity and time on the basis of the original text, and also has encryption features.

Verify signature process:

Authenticate with own key:

The software sends the part of the file to be signed encrypted by the private key to the hardware, and then issues a decryption command, requiring the hardware to use its own private key to decrypt it. The hardware will use the private key to decrypt the incoming data, and then return the decrypted data to the software.

Then, the software sends the part of the file to be signed encrypted by the private key 2 into the hardware, and then sends a decryption command, requiring the hardware to decrypt it with its own private key 2. The hardware will use the private key 2 to decrypt the input data, and then return the decrypted data to the software.

The software compares the two decrypted results before and after. If they are not the same, it means that the file has been modified. At this time, an error can be prompted and the different places will be displayed. If they are the same, it means that the signed file has not been modified. Since the decrypted data contains the ID of the hardware, the time of signing and the original original content, the software can separate these data and generate the signature. An original copy of a document, showing who signed it and when it was signed.

Use the encryption key output by the signing hardware to verify on any signing tool (not including itself):

When verifying the signature file, the signature tool that generates the signature file must output its encrypted private key after generating the signature file (use the public key to encrypt the two private keys in the hardware, and then output).

The software first obtains the encrypted private key of the signature tool (referred to as the original signature tool) of the signature file, and then sends the encrypted private key to the signature tool to be verified (referred to as the verification tool for short), and the verification tool uses the public The key decrypts the input encryption key and generates two private keys of the original signature tool, so that the verification tool can use the private key of the original signature tool to verify the files signed by the original signature tool. The verification method Same as above, not repeated here.

Use the key encrypted by the random number output by the signing hardware to verify on the specified signing tool:

The biggest difference between this verification method and the previous verification method is that no authorized signature tool can verify it, which increases the security of the signed file, and will not cause any damage due to the theft of the output encryption key. Signed documents are viewed by unauthorized persons.

The authorized signing tool (referred to as the authorized tool) first generates a random number, then mixes the random number with its own ID according to certain rules, then encrypts it with the public key, and then outputs the encrypted data.

The software sends the output encrypted data to the original signature tool. The original signature tool uses the public key to decrypt the data, restores it to a random number and the authorized tool ID, and then uses the random number to encrypt the private key in the original signature tool. Encrypt with the key, and then output the encrypted private key and the authorized tool ID. When the software obtains the encrypted private key, it will display the authorized tool ID to the user to verify its identity.

The software sends the encryption key encrypted by the random number to the authorized tool, and the authorized tool uses the random number generated by it to decrypt the encrypted key, and generates two private keys of the original signature tool, so that the verification tool can use The private key of the original signature tool has verified the file signed by the original signature tool. The verification method is the same as above, and will not be repeated here.

The private key, hardware ID and identity confirmation of the hardware applicant are uniformly distributed and managed by an issuing organization, so that the uniqueness of the private key and hardware ID can be guaranteed.

Claims (3)

1. a digital signature method is characterized in that, comprises the steps:

Signature step:

Generate signature file earlier: the file that software will be signed is divided into a plurality of packets, then these packets is sent in batches in the signature hardware, sends encrypted instruction then; At first mix with hardware ID and current time the data of input hardware inside according to certain rule, use two privately owned secret keys of hardware inside respectively mixed data to be encrypted then, export to software then respectively, after software receives this two set of encrypted data, these data are reorganized into a new signature file again; This signature file comprises two parts, and a part is by a pair of original text encrypted ciphertext of privately owned secret key, and another part is by two pairs of original text encrypted ciphertext of privately owned secret key; This newly-generated signature file just has the uniqueness based on hardware identity and time on the basis of original text, also have encryption feature simultaneously;

The certifying signature step: described signature verification step is chosen any one kind of them from following three kinds of verification steps:

1) use self secret key to verify:

The part of being encrypted by privately owned secret key one of the file that software will be signed is sent in the hardware, sends decryption instructions then, requires hardware to use a pair of its of privately owned secret key of self to be decrypted; Hardware inside will use privately owned secret key one that the data of sending into are decrypted, and the data after will deciphering then return to software;

The part that the file that software will be signed is encrypted by privately owned secret key two is sent in the hardware, sends decryption instructions then, requires hardware to use the privately owned secret key two of self that it is decrypted; Hardware is inner to use privately owned secret key two that the data of sending into are decrypted, and the data after will deciphering then return to software;

Software compares the result of twice deciphering in front and back, if inequality, the expression file is modified, and the prompting mistake shows different places; If it is identical, file behind the expression signature is not modified, decipher the time and the original textual content that include the ID of hardware in the back data of reducing and signing when, software comes out these data separating, generate the original text copy of this signature file, the time when showing signer identity and signature simultaneously;

2) use the cryptographic keys of exporting by signature hardware on any one signature instrument, to verify:

When carrying out the certifying signature file, the signature instrument that generates signature file must be exported the privately owned secret key of its encryption after generating signature file, use publicly-owned secret key that two privately owned secret keys in the hardware are encrypted, then output;

Privately owned secret key after the signature instrument that software at first obtains this signature file is encrypted, the signature instrument of this signature file is called for short former signature instrument, privately owned secret key after will encrypting is then sent into the signature instrument that will verify, use of the cryptographic keys deciphering of publicly-owned secret key by verification tool to input, generate two privately owned secret keys of former signature instrument, like this, verification tool just can use the privately owned secret key of former signature instrument that the file of being signed by former signature instrument is verified that verification method is the same;

3) use the secret key of being exported by signature hardware by random number encryption to verify on the signature instrument of appointment: the signature instrument that is authorized at first generates a random number, then this random number is mixed by certain rule with self ID, use publicly-owned secret key that it is encrypted then, then data encrypted is exported;

Software is sent to former signature instrument with the data encrypted of output, former signature instrument uses publicly-owned secret key that these data are decrypted, be reduced into random number and be authorized to appliance id, use random number that the privately owned secret key in the former signature instrument is encrypted then, privately owned secret key after will encrypting then and be authorized to appliance id output, in the time of privately owned secret key after software to be encrypted, will be authorized to appliance id and be shown to the user, to verify its identity;

Software will be sent into by the cryptographic keys behind the random number encryption and be authorized to instrument, being authorized to instrument uses the random number of its generation that cryptographic keys is decrypted, generate two privately owned secret keys of former signature instrument, verification tool is verified the file of being signed by former signature instrument with the privately owned secret key of using former signature instrument.

2. one kind is adopted the digital signature instrument of digital signature method according to claim 1, it is characterized in that, comprise the instrument box body, be arranged on the single-chip microcomputer in the box body, in box body, also be provided with following hardware cell: hardware encipher algorithm unit and decipherment algorithm unit with described single-chip microcomputer exchange message, unique ID generating unit, at least one publicly-owned secret key unit, article at least two, privately owned secret key unit, the randomizer unit, unit, random number storage area, the clock counter unit also is provided with the peripheral interface and the long-term electric supply installation that are used for carrying out with ancillary equipment communication on box body.

3. according to the described digital signature instrument of claim 2, it is characterized in that, in described box body, be provided with many publicly-owned secret key unit and many privately owned secret key unit.

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