Method and system for providing a tamper-proof storage of an audit trail in a database

• US 6,968,456 B1
• Filed: 08/08/2000
• Issued: 11/22/2005
• Est. Priority Date: 08/08/2000
• Status: Expired due to Term

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Novell Incorporated (Open Text Corporation)
• Inventors: Tripathi, Aridaman, Murthy, Madhusudhana H. S.
• Primary Examiner(s): Barrón, Jr., Gilberto
• Assistant Examiner(s): Gurshman, Grigory
• Application Number:
  US09/634,445
• Time in Patent Office: 1,932 Days
• Field of Search: 713/177, 713/178, 713/185, 713/193, 713/174, 707/202, 707/9
• US Class Current: 713/185
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 2221/2101 Auditing as a secondary aspect
• CPC Class Codes: G06F 2221/2151 Time stamp
• CPC Class Codes: H04L 9/3234 involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99939 Privileged access
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A method and system is provided for a tamper-proof storage of one or more records of an audit trail in a database. Since the integrity of the database records may be vulnerable to actions taken by a user such as a privileged database administrator, a mechanism is provided to efficiently detect any changes made by him to the database records. The method creates one or more authentication tokens, and generates one or more validation tokens from the authentication tokens through a combination of a hashing process and an encryption process. Once the validation tokens are created, they are further integrated into the records in the database. The authentication tokens are written to a secured information storage in a predetermined format by a writing machine inaccessible by the user but accessible by the auditor. When an authorized person such as an independent auditor who needs to check the integrity of the records, he can detect a tampering of the records by comparing a validation token computed from the stored validation token with the validation token integrated in the record.

Claims

1. A method for providing a tamper-proof storage of an audit trail having one or more records for a database system, the integrity of the audit trail being vulnerable to actions taken by an access-privileged user, the method comprising:

creating an initial authentication token and initial validation token for the audit trail from a Pseudo Random Number, a Timestamp, and a preliminary authentication token;

saving the initial authentication token as a current authentication token in a predetermined format in a secured information storage;

generating one or more validation tokens and authentication tokens sequentially from the initial authentication token and the initial validation token through a combination of at least one hashing process and at least one encryption process;

integrating the generated validation tokens in the records of the audit trail by a writing machine which is decoupled from the database and inaccessible by the user; and

validating, by an authorized auditor, the records of the audit trail by using the generated validation tokens in order to detect a tampering of the audit trail,

wherein a writing and reading access to the secured information storage is given to the writing machine and only a reading access is given to the auditor, and wherein the Pseudo Random Number, the Timestamp, and the preliminary authentication token are saved in the secured information storage.

2. The method of claim 1 further comprising installing an initial record of the audit trail by the auditor.

3. The method of claim 2 wherein the initial record of the audit trail has null content.

4. The method of claim 1 wherein the step of creating further includes:

creating the initial validation token from the Pseudo Random Number, the Timestamp, and the preliminary authentication token by the auditor;

creating the initial authentication token through a hashing process after concatenating the preliminary authentication token with the initial validation token; and

integrating the initial validation token to the initial record of the audit trail.

5. The method of claim 1 wherein the step of generating further includes:

creating the validation token for a selected record by encrypting the selected record with the then current authentication token saved in the secured information storage; and

updating the value of the current authentication token by generating the authentication token through a hashing process after concatenating the created validation token with the then current authentication token saved in the secured information storage,

wherein the above steps are conducted repeatedly for various records in the audit trail, and wherein any prior value of the current authentication token saved in the secured information storage is irreversibly deleted when an updated value is obtained.

6. The method of claim 1 wherein the step of generating further includes:

creating a validation token for a selected record by concatenating, hashing, and encrypting the selected record with the saved authentication token; and

updating the value of the current authentication token by generating the authentication token further through encrypting the created validation token,

wherein the above steps are conducted repeatedly for various records in the audit trail, and wherein any prior value of the current authentication token saved in the secured information storage is irreversibly deleted when an updated value is obtained.

7. The method of claim 1 wherein the step of integrating further includes adding a predetermined field to the record.

8. The method of claim 1 wherein the step of validating further includes:

obtaining the saved Pseudo Random Number, Timestamp, and preliminary authentication token from the secured information storage;

computing sequentially the validation tokens for the records of the database based on the obtained Pseudo Random Number, Timestamp, and selected preliminary authentication token;

comparing each computed validation token with the integrated validation token in the record,

wherein a tampering of the record is detected if the computed validation token is different from the integrated validation token in the record.

9. A computer program for providing a tamper-proof storage of an audit trail having one or more records for a database, the integrity of the trail being vulnerable to actions taken by an access-privileged user, the program comprising:

program means for creating an initial authentication token and initial validation token of the audit trail from a Pseudo Random Number, a Timestamp, and a preliminary authentication token;

program means for saving the initial authentication token as a current authentication token in a predetermined format in a secured information storage;

program means for generating one or more validation tokens and authentication tokens sequentially from the initial authentication token and the initial validation token through a combination of at least one hashing process and at least one encryption process;

program means for integrating the generated validation tokens in the records of the audit trail by a writing machine which is decoupled from the database and inaccessible by the user; and

program means for validating, by an authorized auditor, the records of the audit trail by using the generated validation tokens in order to detect a tampering of the audit trail,

wherein a writing and reading access to the secured information storage is given to the writing machine and only a reading access is given to the auditor, and wherein the Pseudo Random Number, the Timestamp, and the preliminary authentication token are saved in the secured information storage.

10. The program of claim 9 further comprising program means for installing an initial record of the audit trail by the auditor.

11. The program of claim 10 wherein the initial record of the audit trail has null content.

12. The program of claim 9 wherein the program means for creating further includes:

program means for creating the initial validation token from the Pseudo Random Number, the Timestamp, and the preliminary authentication token by the auditor;

program means for creating the initial authentication token through a hashing process after concatenating the preliminary authentication token with the initial validation token; and

program means for integrating the initial validation token to the initial record of the audit trail.

13. The program of claim 9 wherein the program means for generating further includes:

program means for creating the validation token for a selected record by encrypting the selected record with the then current authentication token saved in the secured information storage; and

program means for updating the value of the current authentication token by generating the authentication token through a hashing process after concatenating the created validation token with the then current authentication token saved in the secured information storage,

wherein the above steps are conducted repeatedly for various records in the audit trail, and wherein any prior value of the current authentication token saved in the secured information storage is irreversibly deleted when an updated value is obtained.

14. The program of claim 9 wherein the program means for generating further includes:

program means for creating a validation token for a selected record by concatenating, hashing, and encrypting the selected record with the saved authentication token; and

program means for updating the value of the current authentication token by generating the authentication token further through encrypting the created validation token, wherein the above steps are conducted repeatedly for various records in the audit trail, and

wherein any prior value of the current authentication token saved in the secured information storage is irreversibly deleted when an updated value is obtained.

15. The program of claim 9 wherein the program means for integrating further includes program means for adding a predetermined field to the record.

16. The program of claim 9 wherein the program means for validating further includes:

program means for obtaining the saved Pseudo Random Number, Timestamp, and preliminary authentication token from the secured information storage;

program means for computing sequentially the validation tokens for the records of the audit trail based on the obtained Pseudo Random Number, Timestamp, and selected preliminary authentication token; and

program means for comparing each computed validation token with the integrated validation token in the record,

wherein a tampering of the record is detected if the computed validation token is different from the integrated validation token in the record.

17. A computer system for providing a tamper-proof storage of an audit trail having one or more records for a database, the integrity of the trail being vulnerable to actions taken by an access-privileged user, the system comprising:

means for creating an initial authentication token and initial validation token of the audit trail from a Pseudo Random Number, a Timestamp, and a preliminary authentication token;

a secured information storage means for saving the initial authentication token as a current authentication token in a predetermined format;

means for generating one or more validation tokens and authentication tokens sequentially from the initial authentication token and the initial validation token through a combination of at least one hashing process and at least one encryption process;

means for integrating the generated validation tokens in the records of the audit trail; and

means for validating, by an authorized auditor, the records of the audit trail by using the generated validation tokens in order to detect a tampering of the audit trail,

wherein the secured information storage is inaccessible by the user but accessible by the auditor, a writing and reading access to the secured information storage is only given to a writing machine which is decoupled from the database and inaccessible by the user, and wherein the Pseudo Random Number, the Timestamp, and the preliminary authentication token are saved in the secured information storage.