Method, server and computer program for security management in database

1. A non-transitory computer readable medium having a program for security management in a database to allow a computing device to perform steps including:

reading one or more data encrypted at a column level from any of a persistent storage medium or a memory;

decrypting one or more data encrypted at the column level to generate one or more decrypted data;

generating an index table based on the one or more generated decrypted data; and

performing an operation of encrypting the generated index table at a block level,

where the instructions for the program are executed by one or more processors in the computing device,

wherein, in a column-level encryption, a first encryption key is generated by a column unit and, in a block-level encryption, a second encryption key is generated by a block unit or by a unit of the block or more, and wherein the first encryption key and the second encryption key are encrypted through a master key to be stored in a data dictionary of a memory, and the master key is stored in any of an external storage medium or a database server.

2. The non-transitory computer readable medium of claim 1 ,

wherein the steps further include: storing the index table encrypted at the block level in the persistent storage medium.

3. The non-transitory computer readable medium of claim 1 ,

wherein the operation of encrypting the generated index table at the block level is performed when a background process intends to write the block in the memory in the persistent storage medium.

4. The non-transitory computer readable medium of claim 1 ,

wherein the steps further include:

receiving a storage request for the one or more data;

determining whether a column in which the one or more data are to be stored is an encrypted column and whether the column in which the one or more data are to be stored is a column of which an index is set; and

encrypting and storing the one or more data at the column level when the column in which the one or more data are to be stored is the encrypted column and the column in which the one or more data are to be stored is the column of which the index is set.

5. The non-transitory computer readable medium of claim 4 ,

wherein the encrypting and storing of the one or more data at the column level includes storing the one or more data encrypted at the column level in a data segment of the persistent storage medium.

6. The program non-transitory computer readable medium of claim 4 ,

wherein the first and second encryption keys have different values.

7. The non-transitory computer readable medium of claim 1 ,

wherein the steps further include: storing the index table encrypted at the block level in an index segment of the persistent storage medium.

8. The non-transitory computer readable medium of claim 1 ,

wherein the generating of the index table includes generating the index table at least partially based on a size attribute for a column in which the one or more decrypted data are to be stored.

9. The non-transitory computer readable medium of claim 1 ,

wherein the generating of the index table is performed based on at least one of a balanced tree (B-tree) index technique, a bitmap index technique, and a function based index (FBI) technique.

10. The non-transitory computer readable medium of claim 1 ,

wherein the encryption and decryption are transparently and automatically performed with respect to a client of the database server.

11. The non-transitory computer readable medium of claim 1 ,

wherein one or more data encrypted at the column level are stored in the persistent storage medium together with an encryption comparison code generated at least partially based on the one or more data values and positional information in which the data values are to be stored.

12. The non-transitory computer readable medium of claim 1 , wherein the steps further include:

encrypting and storing the one or more data at the column level,

wherein the column in which the one or more data are to be stored is an encrypted column and a column in which an index is set.

13. A non-transitory computer readable medium storing a program for security management in a database to allow a computing device to perform steps including:

reading an index table encrypted at a block level from a persistent storage medium in response to an index inquiry request;

decrypting the index table encrypted at the block level to generate the decrypted index table;

performing index scan based on the decrypted index table;

reading one or more data encrypted at a column level corresponding to a result of the index scan, from the persistent storage medium; and

decrypting one or more data encrypted at the column level to generate one or more decrypted data,

where the instructions for the program are executed by one or more processors in the computing device, and

wherein, in a column-level encryption, a first encryption key is generated by a column unit and, in a block-level encryption, a second encryption key is generated by a block unit or by a unit of the block or more, and wherein the first encryption key and the second encryption key are encrypted through a master key to be stored in a data dictionary of a memory, and the master key is stored in any of an external storage medium or a database server.

14. The non-transitory computer readable medium of claim 13 ,

wherein the index scan result includes a column key and a row ID corresponding to the index inquiry request.

15. The non-transitory computer readable medium of claim 13 ,

wherein the steps further include: generating an index inquiry result value corresponding to the index inquiry request based on one or more decrypted data.

16. A database server having a program for security management, comprising:

at least one hardware processor and a memory configured for

reading an index table encrypted at a block level from a persistent storage medium in response to an index inquiry request,

decrypting the index table encrypted at the block level to generate the decrypted index table,

performing index scan based on the decrypted index table,

reading one or more data encrypted at a column level corresponding to a result of the index scan, from the persistent storage medium, and

decrypting one or more data encrypted at the column level to generate one or more decrypted data; and

a persistent storage medium configured to store a data table including the data encrypted at the column level and an index table encrypted at the block level,

wherein, in a column-level encryption, a first encryption key is generated by a column unit and in a block-level encryption, a second encryption key is generated by a block unit or by a unit of the block or more, and wherein the first encryption key and the second encryption key are encrypted through a master key to be stored in a data dictionary, and the master key is stored in any of an external storage medium or the database server, where any software portions of the program are stored in the memory.

17. The database server of claim 16 , further comprising:

the at least one processor further configured to generate the index table based on the one or more decrypted data, and to perform an operation of encrypting the generated index table at the block level.