Method and apparatus for detecting data tampering within a database

• US 20070294205A1
• Filed: 06/14/2006
• Published: 12/20/2007
• Est. Priority Date: 06/14/2006
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Xu, MingKang, Wong, Daniel Manhung
• Granted Patent: US 8,190,915 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2255 Hash tables
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures

Abstract

One embodiment of the present invention provides a system that facilitates detecting data tampering within a table in a database. The system operates by hashing a row in the table to create a row-hash. The system then hashes a block of consecutive row-hashes to create a block-hash. Finally, the system signs the block-hash with an encryption key, so that tampering with data in the row will result in an invalid row-hash and an invalid block-hash.

Claims

1. A method for detecting data tampering within a table in a database, the method comprising:

hashing a row in the table to create a row-hash;

hashing a block of consecutive row-hashes to create a block-hash; and

signing the block-hash with an encryption key, wherein tampering with data in the row will result in an invalid row-hash and an invalid block-hash.

2. The method of claim 1, wherein hashing the block further involves hashing a signature of a previous block-hash along with the block of consecutive row-hashes to facilitate the detection of missing blocks.

3. The method of claim 1, wherein the block-hash is stored in the table.

4. The method of claim 1, wherein the row-hash is stored in the corresponding row.

5. The method of claim 1, wherein the table is an insert-only table, wherein data may only be inserted into the table, and wherein no user, including an administrator, may delete or update data which is inserted into the table.

6. The method of claim 1, wherein signing the block-hash with an encryption key involves signing the block-hash with a private-key of a Public Key Infrastructure (PKI) key pair.

7. The method of claim 6, wherein the private-key is stored in an External Security Module (ESM).

8. The method of claim 6, wherein the private-key is held by a third-party.

9. A computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for detecting data tampering within a table in a database, the method comprising:

hashing a row in the table to create a row-hash;

hashing a block of consecutive row-hashes to create a block-hash; and

signing the block-hash with an encryption key, wherein tampering with data in the row will result in an invalid row-hash and an invalid block-hash.

10. The computer-readable storage medium of claim 9, wherein hashing the block further involves hashing a signature of a previous block-hash along with the block of consecutive row-hashes to facilitate the detection of missing blocks.

11. The computer-readable storage medium of claim 9, wherein the block-hash is stored in the table.

12. The computer-readable storage medium of claim 9, wherein the row-hash is stored in the corresponding row.

13. The computer-readable storage medium of claim 9, wherein the table is an insert-only table, wherein data may only be inserted into the table, and wherein no user, including an administrator, may delete or update data which is inserted into the table.

14. The computer-readable storage medium of claim 9, wherein signing the block-hash with an encryption key involves signing the block-hash with a private-key of a Public Key Infrastructure (PKI) key pair.

15. The computer-readable storage medium of claim 14, wherein the private-key is stored in an External Security Module (ESM).

16. The computer-readable storage medium of claim 14, wherein the private-key is held by a third-party.

17. An apparatus configured to detect data tampering within a table in a database, comprising:

a row-hashing mechanism configured to hash a row in the table to create a row-hash;

a block-hashing mechanism configured to hash a block of consecutive row-hashes to create a block-hash; and

an encryption mechanism configured to sign the block-hash with an encryption key, wherein tampering with data in the row will result in an invalid row-hash and an invalid block-hash.

18. The apparatus of claim 17, wherein the block-hashing mechanism is further configured to hash a signature of a previous block-hash along with the block of consecutive row-hashes to facilitate the detection of missing blocks.

19. The apparatus of claim 17, wherein the block-hashing mechanism is further configured to store the block-hash in the table.

20. The apparatus of claim 17, wherein the row-hashing mechanism is further configured to store the row-hash in the corresponding row.

21. A method for detecting data tampering within a table in a database, the method comprising:

upon data being inserted into a row in the table, hashing the row to create a row-hash; and

storing the row hash at a location associated with the row in the database;

wherein tampering with data in the row will result in an invalid row-hash.

22. The method of claim 21, wherein the method further comprises:

hashing a block of consecutive row-hashes to create a block-hash;

wherein tampering with data in any row in the block will result in an invalid block-hash.

23. The method of claim 22, wherein the method further comprises signing the block-hash with an encryption key.

24. The method of claim 22, wherein hashing the block further involves hashing a signature of a previous block-hash along with the block of consecutive row-hashes to facilitate the detection of missing blocks.

25. The method of claim 22, wherein the block-hash is stored in the table.

26. The method of claim 21, wherein the row-hash is stored in the corresponding row.

27. The method of claim 21, wherein the table is an insert-only table, wherein data may only be inserted into the table, and wherein no user, including an administrator, may delete or update data which is inserted into the table.

28. A computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for detecting data tampering within a table in a database, the method comprising:

upon data being inserted into a row in the table, hashing the row to create a row-hash; and

storing the row hash at a location associated with the row in the database;

wherein tampering with data in the row will result in an invalid row-hash.