JP7026971B2 - Digital field survey record reliability model system and method - Google Patents

Description

The present invention belongs to the technical field of protecting the integrity of data in digital data processing, and specifically relates to a digital field survey record reliability model system.

With the progress of science and technology, various police activities in the police department have entered the digital age. A crime scene investigation is usually a person involved in a crime in accordance with the law in order for an investigator to confirm the facts of the crime, collect evidence of the crime, and identify and expose the criminal after a criminal case has occurred. Refers to on-site visits and inspections conducted on things, places, goods, people, corpses, etc., and criminal on-site investigations are conducted using criminal science and technology means in accordance with national laws and regulations. Must be done within a specific spatial area. The site survey record is a set of documents and attachments formed after the site survey work is completed, mainly on-site brush records, site photographs, site videos, site audio, traces, and various types of physical material. Includes evidence, electronic data evidence of each type, drawings, etc. Among these on-site survey records, digitization of photographs, videos, and audio has already been realized, and on-site survey records in the form of brush records, drawing drawings, etc. will be sent to the subsequent on-site inspection information system. Digitization is realized by manual input by the investigator.

Field surveys are a very strong task with a procedural element, and even small flaws in the workflow can have serious consequences. For example, the collection of evidence may be inadequate or the trace evidence may be damaged. In the meantime, the loss of credibility of the field survey record is a catastrophic result, which makes the origin of the entire evidence chain unacceptable and, in turn, invalidates the entire field survey work. The conventional on-site investigation record trust mechanism is based on "signature", and each paper-based on-site investigation record and trace evidence collection list are recorded by the investigator by signing the name by hand. Reliability must be guaranteed and generally two or more investigators' signatures are required to prevent falsification of records. However, in actual field survey work, the norm of "signature" has many problems. There are mainly the following two cases. One is a retrofit signature. For convenience, some investigators do not sign records and lists as requested at the time of the field investigation, but then add their signatures. The second is an alternative signature. That is, some investigators are not involved in the field investigation and sign or sign on behalf of others as procedurally necessary.

All of the above actions raise doubts about the reliability of the field investigation records and have a hidden adverse effect on the subsequent judicial certification work. In the digital age, even if the risks of manual signatures mentioned above are avoided, it is urgently necessary to solve how to effectively guarantee the reliability of a large amount of digital field survey records. It has become an issue.

In the conventional patent document, the invention of the application number "CN201710140360.5" and the name "method and system for determining electronic evidence in the field" discloses a method and system for determining electronic evidence in the field. This method obtains the user's login information, selects the user's authority and starts recording for user operations, collects on-site eDiscovery, and stops recording for user operations. , Generate the recorded result as a user operation log, perform a completeness check on the acquired electronic evidence, generate the acquired electronic evidence as an electronic report, and generate the completeness check result of the electronic evidence. Including adding to eDiscovery and uploading eDiscovery, these are jointly done by modules such as User Login Module, Evidence Collection Module, Integrity Check Results Module, Report Generation Module and Upload Module. It has been realized. The present invention has solved to some extent the technical problem that photographs and videos taken by conventional mobile terminals are easily tampered with, but the problem of retrofit signatures and alternative signatures has not yet been solved.

In view of the above-mentioned problems in the above-mentioned prior art, the present invention uses a method such as a cryptographic digital signature or hash to perform a reliability operation on a digitization field survey record to perform all digital operations. Regarding on-site investigation records, from the start of recording to submission to the court, it is possible to guarantee that the digitized information such as the contents of the record, the recorder, the recording location, the recording time, etc. is complete and has not been tampered with. We propose a survey record reliability model system.

In order to achieve the above object, the technical proposal adopted by the present invention is a digital field survey record reliability model system, in which the digital field survey record reliability model is described as T, and T = (E, A). , DR, TR, Sign), where E is an entity in the model, E = _{ S, Ci _} , S is a server, and Ci is a field survey terminal device. , S and _Ci are connected via a wireless communication network, where A is a set of cryptographic algorithms in a trust model, and server S uses a public key and an asymmetric cryptographic algorithm in A. Generate a private key, DR is a set of all digital field survey records, DR = {dr _i | dr _i ∈ {digital photo, digital brush recording, video, audio} _} , DR information is Ci Stored within, TR is a set of reliable digital field survey records, TR = {tr _i | tr _i = dr _i + Sign (dr _i )}, and Sign is a reliability operation. The reliability operation uses the above-mentioned private key, the DT is the date and time and is input to the server S, and the GPS is the current geographic position coordinate information of _Ci and is input to _Ci . ..

Further, the on-site investigation terminal device _Ci is associated with the status of the investigator who uses the device, and is dedicated to the investigator.

Preferably, the field survey terminal device Ci is equipped with a high-definition camera, a GPS sensor, Wi- _fi , and access capability using a 4G signal.

Further, the set of cryptographic algorithms is an asymmetric key pair generation algorithm, a symmetric key algorithm, a signature algorithm and a hash algorithm.

The present invention further proposes a method for performing a reliability operation using the above digital field survey record reliability model system, which specifically includes the following initialization process, registration process, and signature process. ..

1. Initialization process Using the RSA algorithm, a public key and a private key are generated for the server S and described as PK _s and SK _s . PK _s is saved in the digital certificate and described as Cert _s , and is described as SK. _s is stored locally on the server S using an AES algorithm (AES, Advanced Encryption Standard, Advanced Encryption Standard) and a strong key.

2. Registration process It is necessary to complete the registration before using the site survey terminal device for the first time, the server issues a certificate to the site survey terminal device, sends the private key to the terminal in encrypted form, and All field survey terminal equipment and server public keys are stored on the server and can be visited publicly.

3. Signature process 1. The site survey terminal device Ci _{collects the site survey data dr n by} the device and collects it.
2. 2. The site survey terminal device _Ci acquired the geographic location coordinates from which the site survey data was collected by its own GPS sensor, and described it as _Gn .
3. 3. The site survey terminal device _Ci requests a trust time stamp from the server and
4. The server returns the current time dt _n to the field survey terminal device, puts a digital signature to guarantee the reliability of the time, and the reply content is Timestamp _n = dt _n + sign (SK _s , dt _n ). can be,
5. The site survey terminal device Ci _verifies the reliability of time, and the following 6. The site survey data dr _n is subjected to the reliability processing as described above, and the reliable site survey data tr _n is obtained.

Further, as the above registration process, specifically, the site survey terminal device Ci sends a registration request and a key _i , which is a password set by the owner of the terminal i, to the server S, and the server S sends the key _i to the server S. A key pair (PK _Ci , SK _Ci ) is generated for _Ci , E and D are the encryption and decryption functions of the symmetric cryptographic algorithm AES, respectively, and Sign is the asymmetric cryptographic algorithm DSA (Digital Signature). It is signed with Algorithm) and includes that H is a hash function of the SHA1 (Secure Hash Algorithm) algorithm.

Further, step 3. of the above signature process. In, the field survey data can be text, images, audio, or video.

Ｓ２：オリジナルデータＯ内のタイムスタンプが有効であるかを検証し、以下の式が成立するかを確認し、

成立の場合は、次のステップに進み、そうでない場合は、検証失敗の旨を提示し、検証過程を中止し、
Ｓ３：オリジナルデータＯの信頼性を検証し、以下の式が成立するかを確認し、

成立の場合は、検証が成功となり、そうでない場合は、検証失敗の旨を提示し、
Ｓ４：検証過程が終了する。 If the data in the above record is falsified, the verification fails, and the process of verifying the reliable field survey data tr _n is as described in S1 to S4 below.

S2: Verify that the time stamp in the original data O is valid, and confirm that the following formula holds.

If it is successful, proceed to the next step. If not, indicate that the verification has failed, stop the verification process, and stop the verification process.
S3: Verify the reliability of the original data O, check if the following formula holds, and

If it is successful, the verification is successful, and if not, it is indicated that the verification has failed.
S4: The verification process is completed.

Compared with the prior art, the present invention has the following beneficial technical effects.

1. The present invention generates a reliable on-site investigation digital record by performing a reliability process on the digital record generated in the crime on-site investigation, and the record includes the on-site investigation data, the collection place, and the like. Includes collection time and collector information.
2. The reliable record signs the record using the private key of the terminal and stores the collector of the record, and the reliability of the record is manifested in tamper-proof and undeniable. The terminal is dedicated to a specific person, and the digital signature reveals from which terminal the data was collected, and the owner of the terminal cannot deny it.
3. If the field survey record is falsified, it will be discovered through the verification process. That is, if the data in the record is falsified, the verification will fail. It effectively solved the technical problem that the video was easily tampered with, and also solved the problem of how to prevent retrofitting and alternative signatures.

FIG. 1 is a structural diagram of a digital field survey record reliability model. FIG. 2 is a flowchart of terminal registration. FIG. 3 is a flowchart of reliability verification of field survey data.

The present invention will be described in more detail with reference to the drawings.

FIG. 1 shows a structural diagram of a trust model. In the present invention, the digital field survey record reliability model is referred to as T, and T = (E, A, DR, TR, Sign), where E is an entity in the model and E = {S, C _i . _} , S is a server, Ci is a field survey terminal device, S and _Ci are connected via a wireless communication network, and A is a set of cryptographic algorithms in the model. And DR is a set of all digital field survey records.

DR = {dr _i | dr _i ∈ {digital photography, digital brush recording, video, audio}}, TR is a set of reliable digital field survey records, and TR = {Sign (dr _i )}. Yes, Sign is a reliability operation, DT is the date and time, and GPS is the current geographic location coordinates of _Ci .

The process of performing the reliability operation using this system is as follows.

(1) Initialization process The public key and private key are generated for the server S using the RSA algorithm and described as PK _s and SK _s , and the PK _s are saved in the digital certificate and described as Cert _s . The SK _s is stored locally on the server using the AES algorithm and a strong key.

(2) Registration process FIG. 2 is a flow chart of terminal registration, in which the terminal device Ci is a handheld device for on-site investigation of an investigator, and the device includes a high-definition camera, a GPS sensor, Wi- _fi , and a 4G signal. It is equipped with functions such as access capability and logging, and each terminal device is associated with the status of one investigator on a one-to-one basis and is dedicated to that investigator. Before using the terminal device for the first time, it is necessary to complete the main registration process.

In FIG. 2, the Key _i is a password set by the owner of the terminal i, and is intended to protect the security of the private key. E and D are cryptographically symmetric cryptographic algorithm AES encryption and decryption functions, Sign is signed using the asymmetric cryptographic algorithm DSA, and H is the hash function of the SHA1 algorithm. The purpose of this step is to have the server issue a certificate for the terminal and send the private key in encrypted form to the terminal, and all terminals and the public key of the server are stored on the server. Can be visited publicly.

(3) Signature process 3.1, the terminal Ci _{collects the field survey data dr n by} the device, and the data can be text, image, audio, or video.
3.2, The terminal _Ci acquires the geographic location coordinates from which the field survey data was collected by its own GPS sensor and writes it as _Gn .
3.3, request a trust time stamp from the server,
3.4, the server returns the current time dt _n to the terminal and puts a digital signature to guarantee the reliability of the time, and the reply content is Timestamp _n = dt _n + sign (SK _s , dt _n ). ,
3.5, The terminal Ci verifies the reliability of the time and performs the reliability processing on the site survey data dr _n as _{follows to obtain the reliable site survey data tr n .}

FIG. 3 is a flowchart of reliability verification of the field survey data, showing the entire process of verifying the reliable field survey record tr _n , and if the data of the record is falsified, the verification fails. become.

For convenience of implementation of the present invention by those skilled in the art, one specific embodiment is given.

It is assumed that the initialization operation by the server S has already been completed, the PK _s is open to the outside, and the SK _s is secretly stored. Then, one on-site investigation terminal device C associated with the identity is distributed to the investigator A, and the server has already generated one public key and one private key pair for A. It is assumed that the public key PK _c is open to the outside and the SK _c is secretly stored in the terminal C.

Investigator A obtains one hard disk for PC at the crime scene, takes a picture of this hard disk using his field investigation terminal device C, takes physical evidence, and the file name of the digital photograph of this physical evidence is , DC0017. It is a JPG, and at the same time the terminal device collects the geographical position on its GPS sensor, the value is G = (lat: 22.5024, lng: 113.9383). At the same time, after sending the request for the trust time stamp to the server S, the server sends the current trust time stamp Timestamp (dt = "2018-03-1018: 09: 22") and the server's signature Sign (PK _s , dt). ) Is replied.

The terminal device decrypts Sign (PK _s , dt) using the public key of the server certificate to verify the authenticity of dt, and if it is true and valid, the following steps are used to perform reliable field survey data. Generate tr.

1. 1. DC0017. H (DC0017.JPG), which is the SHA1 hash value of JPG, is calculated.
2. 2. Sign (SK _s , H (DC0017.JPG), G, Timestamp) which is a signature operation by integrating the hash value obtained in the first step with G and Timestamp and using the secret key SK _s of the terminal. And
3. 3. The final reliable field survey data tr is an integration of the following data.
DC0017. JPG, G, Timestamp, Sign (SK _s , H (DC0017.JPG), G, dt)

Next, the reliability verification process for tr is as follows.

1. 1. First, DC0017.Tr is the original data part O. It is decomposed into JPG, G, Timestam and Sign (SK _s , H (DC0017.JPG), G, dt) which is a verification data part V.
2. 2. Verify the reliability of Timestamp in the original data using the server's public key, make sure that dt is equal to Validate (PK _s , Sign (PK _s , dt)), and if so, the time stamp is reliable. If not, stop the verification process and indicate that the verification has failed.
3. 3. DC0017 of the original data part of tr. SHA1 hash operation is performed on JPG and integrated with G and Timestamp dt to form data such as H (DC0017.jpg) + G + dt, which is described as O'.
4. The verification data part of tr is solved using the public key of the server, that is, Validate (PK _s , V), and then it is confirmed whether O'is equal to Validate (PK _s , V). If they are not equal, it indicates that the verification has failed, and if they are equal, the verification is successful, and the photograph DC0017. The JPG is reliable, i.e. the collection time of the photo as physical evidence is 2018-03-1018: 09:22, and the latitude and longitude coordinates of the collection site are (latitude: 22.5024, longitude: 113). .9383).

It is said that the collector is Investigator A and the contents of the photograph have not been tampered with, and the above information is true and valid.

The present invention generates a reliable on-site investigation digital record by performing a reliability process on the digital record generated in the crime on-site investigation, and the record includes the on-site investigation data, the collection place, and the collection time. And the collector's information is included, and this information is guaranteed to be tamper-proof and undeniable.

It should be noted that the description of the above specific embodiments is not intended to limit the present invention, and any modifications, uniform replacements, improvements, etc. made within the spirit and principles of the present invention are all of the present invention. Should be within the scope of protection.

Claims (7)

Digital field survey record A method of performing reliability operations using a reliability model.
The digital field survey record trust model is referred to as T, where T = (E, A, DR, TR, Sign), where E is an entity in the model and E = {S, C _i }. S is a server, Ci _is a field survey terminal device, S and Ci _are connected via a wireless communication network, and A is a set of cryptographic algorithms in a trust model. Server S uses the asymmetric encryption algorithm in A to generate the public and private keys, where DR is a set of all digital field survey records, DR = {dr _i | dr _i ∈ {digital photo, Digital writing, video, audio}}, DR information is stored in Ci, TR is a set of reliable digital field survey records, TR = {tr _i | tr _{i =} dr _i + Sign (dr _i )}, Sign is a reliability operation, the reliability operation uses the above-mentioned private key, DT is a date and time, is input to the server S, and GPS is C. The current geographic location coordinate information of _i , which is input to _Ci and
Including the following (1) initialization process, (2) registration process, and (3) signing process
(1) In the initialization process,
The public and private keys are generated for the server S using the RSA algorithm and are marked as PK _s and SK _s , and the PK _s are saved in the digital certificate, marked as Cert _s , and exposed to the outside, SK. _s is stored locally on server S using the AES algorithm and a strong key.
(2) In the registration process
Registration must be completed before using the field survey terminal device for the first time, and the server issues and encrypts the public key PK _Ci and the private key SK _Ci , which are the key _pairs for the field survey terminal device Ci . The private key SK _Ci is sent to the terminal in the form of a form, and all field survey terminal equipment and the public key of the server are stored in the server and can be visited publicly.
(3) In the signature process,
a) On-site survey terminal equipment Ci _{collects on-site survey data dr n by} the equipment.
b) The on-site survey terminal device _Ci acquires the geographic location coordinates from which the on-site survey data was collected by its own GPS sensor and writes it as _Gn .
c) The site survey terminal device _Ci requests the server for a trust time stamp.
d) The server returns the current time dt _n to the site survey terminal device, puts a digital signature to guarantee the reliability of the time, and the reply content is Timestamp _n = dt _n + sign (SK _s , dt _n) . ) And
_e ) The on-site survey terminal device Ci verifies the reliability of time, performs a reliability process on the on-site survey data dr _n as shown in f) below, and obtains reliable on-site survey data tr _n . ,

A method characterized by being. Specifically, as the registration process, the site survey terminal device C sends a registration request and Ki, which is a password set by the owner of the terminal _Ci , to the server S, and the server S is for _Ci . A key pair (PK _Ci , SK _Ci ) is generated in, E and D are the encryption and decryption functions of the symmetric cryptographic algorithm AES, respectively, and Sign signs using the asymmetric cryptographic algorithm DSA and Validates. However, the method according to claim 1 , wherein the signature is verified using DSA, and H is a hash function of the SHA1 algorithm. The method of claim 1 , wherein in step a of the signing process, the data can be text, images, audio, or video. The process of verifying the reliable field survey data tr _n is as described in S1 to S4 below.

S2: Verify that the time stamp in the original data O is valid, and confirm that the following formula holds.

If it is successful, proceed to the next step. If not, indicate that the verification has failed, stop the verification process, and stop the verification process.
S3: Verify the reliability of the original data O, check if the following formula holds, and

If it is successful, the verification is successful, and if not, it is indicated that the verification has failed.
S4: The verification process is completed,
The method according to claim 1 , wherein the method is characterized by the above. The above-mentioned site survey terminal device C _i Is associated with the identity of the investigator of the device
The method according to claim 1, wherein the method is characterized by the above. The above-mentioned site survey terminal device C _i Is equipped with a high-definition camera, GPS sensor, Wi-fi and 4G signal access capability.
The method according to claim 1, wherein the method is characterized by the above. The set of cryptographic algorithms includes an asymmetric key pair generation algorithm, a symmetric key algorithm, a signature algorithm and a hash algorithm.
The method according to claim 1, wherein the method is characterized by the above.

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