1. Database Security: Concepts, Approaches and Challenges
ĐẠI HỌC BÁCH KHOA TP. HỒ CHÍ MINH
Khoa khoa học máy tính
Database Security: Concepts, Approaches and Challenges
Group 20:
Võ Văn Vinh :
Nguyễn Hoàng Tín :
Vũ Hoàng Việt :
Phạm Văn Vinh :

2. Contents
Part I : DB Security Concepts
Part II : DB Security Approaches
Part III: DB Security Challenges
Part IV: Summary

3. DB Security Concepts Authentication:
Authentication is the process or act of confirming that a user who is
Attempting to log in to a database,
Authorized to log in to a database
Examples:
A mobile phone performs authentication by asking for a PIN.
A computer authenticates a username by asking for the corresponding password

4. DB Security Concepts Authorization
Authorization is a process of defining :
which users are allowed to access to database
what privileges(access to which views, tables, attributes, how long…) of use in the database.
Examples:
The students are not allowed to modify their Academic Records in the University webpage.
The students are allowed to view their Academic Records in a University webpage.

5. DB Security Concepts DB Security Requirements- CIA Triad

6. Database Security Concepts
Confidentiality(Secrecy)
Data Confidentiality : Data is not made available or disclosed to unauthorized individuals
Examples: DB stores Payroll Information =>Not release/modify the individual salaries to/by unauthorized users.

7. DB Security Concepts Integrity Availability:
Data Integrity : Data is changed only in a specified and authorized manner
Examples: A web site of airline Company =>customer’s reservations are not modified arbitrarily.
Availability:
Data Availability:
Data is available when needing to access.
Prevention and recovery from making data be unavailable(Ex … DDoS attacks)
Examples: A web site of airline Company =>The information on flight and reservations are always available.

8. DB Security Concepts Introducing DB Security Approaches
Authentication mechanism
Cryptographic techniques
Designed Features to detect, prevent, or recover from a security attacks
Recovery Subsystem & Concurrence Control
Access Control
Privacy-Preserving Techniques for Database(New)
Privacy-Preserving Data mining(New)
Privacy-Preserving Information Retrieval(New)

9. DB Security Concepts What is Access Control ?
 A process by which users are granted access and certain privileges to systems, resources or information.
Why using Access Control ?
Whenever a user tries to access to a data object, Access Control checks the rights of the user against the set of authorization which states whether the subject can perform a particular action on the data object=>Access Control ensures Data Confidentiality.
Whenever a user tries to modify some data, Access Control verifies the user have the right to modify the data=>Access Control assures the Data Integrity

10. DB Security Approaches
Part II:
DB Security Approaches
-Access Control
Part : Discretionary Access Control(DAC)
Part : Mandatory Access Control (MAC)
-Privacy-Preserving Data Techniques
Part : Privacy-Preserving Data Techniques

11. DB Security Concepts What is Access Control ?
Control of rules determined by security policies for all direct accesses to the system
Why using Access Control ?
Whenever a subject tries to access to a data object, Access Control checks the rights of the user against the set of authorization which states whether the subject can perform a particular action on the data object=>Access Control ensures the Data Confidentiality.
Whenever a subject tries to modify some data, Access Control verifies the user have the right to modify the data=>Access Control assures the Data Integrity

12. DB Security Approaches
There are two Access Control Models:
Discretionary Access Control(DAC)
Mandatory Access Control(MAC)

13. Part II : DB Security Approaches
PART Discretionary Access Control(DAC)

14. Introduction to DAC
defined
Trusted Computer System Evaluation Criteria (TCSEC) is a United States Government Department of Defense (DoD) standard - that sets basic requirements for assessing the effectiveness of computer security controls built into a computer system
Chuẩn đánh giá hệ thống máy tính tin cậy – 1 chuẩn bộ quốc phòng chính phủ mỹ - 1 bộ yêu cầu cơ bản để đánh giá tính hiệu quả của kiểm soát bảo mật trong hệ thống máy tính
A means of restricting access to objects based on the identity of subjects and/or groups to which they belong => Discretionary access control (DAC) is a type of access control

15. Discretionary Access Control (DAC)
owner
object
Discretionary Access Control (DAC):
User can protect what they own.
The owner is given all privileges on their own data.
The owner can define the type of access (read/write/execute/…) and grant access to others.
The typical method of enforcing DAC in a database system is based on the granting and revoking privileges
Discretionary Access Control (DAC): thực hiện dựa trên việc cấp phát và thu hồi quyền truy xuất CSDL
Sử dụng các câu lệnh trong ngôn ngữ truy vấn cho phép DBA và người dùng có quyền hạn được cấp phát quyền cho các người dùng khác
Specifies Users/ groups who can access

16. Cấp tài khoản (account level):
There are two levels for assigning privileges to use the database system
The account/system level: The administrator / DBA specifies the particular privileges that each account holds independently of the objects in the database system.
The object level / relation (or table) level: The administrator can control the privilege to access each individual object in the database system
Cấp tài khoản (account level):
DBA cụ thể quyền của mỗi tài khoản một cách độc lập với các bảng trong CSDL
Cấp bảng (table or relation level):
DBA điều khiển quyền truy xuất cho từng bảng hoặc từng hướng nhìn (view) trong CSDL

17. Introduction to DAC The account/system level privileges (example)
CREATE SCHEMA
CREATE TABLE
CREATE VIEW
ALTER
DROP
MODIFY
SELECT
Alter: apply schema changes such as adding or removing attributes from relations
Drop: to delete relations or views
Modify: to insert, delete, or update tuples
Select: to retrieve information from the database by using a SELECT query

18. Introduction to DAC The relation/object level privileges
Data objects: relation or view
Includes:
INSERT
UPDATE
DELETE
REFERENCE

19. SQL for Data Control Commands: Based on three central objects: GRANT
REVOKE
Based on three central objects:
Users
Database objects
Privileges: select, modify (insert, update, delete), reference

20. SQL for Data Control
GRANT: pass privileges on their own database objects to other users
GRANT <privilege list>
ON <database objects>
TO <user list>
REVOKE: take back (cancel) privileges on their own database objects from other users
REVOKE <privilege list>
FROM <user list>

21. An Example
Suppose that the DBA creates four accounts A1, A2, A3, A4 and wants only A1 to be able to create base relations. Then the DBA must issue the following GRANT command in SQL
GRANT CREATETAB TO A1;
In SQL2 the same effect can be accomplished by having the DBA issue a CREATE SCHEMA command, as follows:
CREATE SCHEMAEXAMPLE AUTHORIZATIONA1;

22. An Example(2)
User account A1 can create tables under the schema called EXAMPLE.
Suppose that A1 creates the two base relations EMPLOYEE and DEPARTMENT
A1 is then owner of these two relations and hence all the relation privileges on each of them.

23. An Example(2)
Suppose that A1 wants to grant A2 the privilege to insert and delete tuples in both of these relations, but A1 does not want A2 to be able to propagate these privileges to additional accounts:
GRANT INSERT, DELETE ON EMPLOYEE, DEPARTMENT TO A2;

24. An Example(2) - Notice
Owner account A1 automatically has the GRANT OPTION, allowing it to grant privileges on the relation to other accounts
However, account A2 cannot grant INSERT and DELETE privileges on the EMPLOYEE and DEPARTMENT tables because A2 was not given the GRANT OPTION in the preceding command.
Suppose that A1 wants to allow account A3 to retrieve information from either of the two tables and also to be able to propagate the SELECT privilege to other accounts. A1 can issue the following command:
GRANT SELECT ON EMPLOYEE, DEPARTMENT TO A3 WITH GRANT OPTION;

25. An Example(2)
Now, A3 can grant the SELECT privilege on the EMPLOYEE relation to A4 by issuing the following command:
GRANT SELECT ON EMPLOYEE TO A4;
Notice that A4 cannot propagate the SELECT privilege to other accounts because the GRANT OPTION was not given to A4.

26. An Example(2)
Now suppose that A1 decides to revoke the SELECT privilege on the EMPLOYEE relation from A3; A1 then can issue this command:
REVOKE SELECT ON EMPLOYEE FROM A3;
The DBMS must now revoke the SELECT privilege on EMPLOYEE from A3, and it must also automatically revoke the SELECT privilege on EMPLOYEE from A4. This is because A3 granted that privilege to A4, but A3 does not have the privilege anymore.

27. An Example(3)
Next, suppose that A1 wants to give back to A3 a limited capability to SELECT from the EMPLOYEE relation and wants to allow A3 to be able to propagate the privilege.
The limitation is to retrieve only the Name, Bdate, and Address attributes and only for the tuples with Dno = 5. A1 then can create the following view:
CREATE VIEW A3EMPLOYEE AS
SELECT Name, Bdate, Address
FROM EMPLOYEE
WHERE Dno = 5;
GRANT SELECT ON A3EMPLOYEE TO A3 WITH GRANT OPTION

28. Role Based Access Control (RBAC)

29. Hierarchies RBAC

30. Constrained RBAC
Add a requirement for enforcing separation of duty (SOD)
Static SOD – SSD (based on user-role assignment)
Impose restriction on role intersections: 2 roles can not have common users
Dynamic SOD – DSD (based on role activation)
Restrict the activation of roles at run time

31. RBAC in commercial DBMS
INFORMIX Online Dynamic Server Version 7.2
Sybase Adaptive Server release 11.5
Oracle Enterprise Server Version 8.0

32. Mandatory Access Control (MAC)
Based on multilevel security (MLS)
Top Secret > Secret > Confidential > Unclassified
Subject has security clearance of a given level
Object has security classification of a given level
Two required properties for confidentiality (Bell-LaPadula)
No read up (simple security property)
Class(S) >= Class(0)
No write down (star property)
Class(S) <= Class(0)

33. Part II: Database Security
PART Mandatory Access Control(MAC)

34. Mandatory Access Control (MAC)
Polyinstantiation

35. Mandatory Access Control (MAC)
Pros
Ensure a high degree of protection, prevent any illegal flow of information.
Suitable for military and high security types of applications.
Cons:
Require strict classification of subjects and objects
Applicable to few environments.

36. Part II : Database Security Approaches
PART Privacy-Preserving Data Techniques
Ky thuat giu gin thong du lieu ca nhan

37. Privacy-Preserving Data Techniques
Why needing Privacy-Preserving Data Techniques ?
Importance of data representation
Increasing number of data set including Individual Data
Data availability causes the serious threats for the privacy of Individuals and Organizations

38. Privacy-Preserving Data Techniques
Modifying the released data by removing items related to Individuals(data anonymity).
Problems : The remaining data can be linked with others infos, so people can recover the privacy data
Solutions : Generalizations Techniques (Relations to Fuzzy Concepts)

39. Privacy-Preserving Data Techniques
Privacy-Preservation Data in Data Mining Context
Causes: Data mining techniques may recover the removed information
All approaches are based on modifying or perturbing data
Developments are based Commutative Encrypted Techniques
Data mining is a new effective tool to mine data

40. Privacy-Preserving Data Techniques
Hippocratic Databases
Incorporating privacy protection in relational database system.
Privacy policies stored in privacy-policy tables
Privacy authorization stored in privacy-authorization tables
Privacy authorization defines authorized users
Data mining is a new effective tool to mine data

41. PART III Database Security CHALLENGES

42. Database Security Challenges
Data quality & Completeness
Data quality : A perception or an assessment of data's fitness to serve its purpose in a given context. 
Data Completeness : Data is not modified comparing with the original
Data quality : la su hieu biet va danh gia su phu hop cua du lieu cho muc dich cua no tron 1 ngu canh nao do
Data Completeness : Du lieu khong dc sua so voi ban goc cua no.
Perception : Hieu biet
Assessment : Danh gia
fitness : Khop voi

43. Database Security Challenges
Data quality & Completeness
Is data complete and of acceptable quality ?
Is data from Web is relyable ?
How to assess and attest the quality of data ?
Techniques and organizational solutions
Quality stamps
Providing more effective integrity verification
Tools for assessment of data quality
Application-level recovery
Assess : Danh gia
Attest : Chung nhan

44. Database Security Challenges
Intellectual Property Rights(IPR)
Who create data
Can be illegal if using this data
Techniques
Watermaking techniques for relational data are used to detect IPR violations

45. Database Security Challenges
Database Survivability
Confinement : Actions to eliminate the attacker’s access
Damage assessment: Determine the problem including failed function and corrupted data
Reconfiguration : Run in safe-mode while recovery
Repair:Recover data, reinstall failed system
Fault treatment:Identify the weakness and prevent the recurrence of the faults
Confinement: chong lai va cach li nhung su tan cong
Damage assessment: danh gia muc do hu hai

46. Database Security Challenges
Access control and privacy for mobile users
Mobile is popular and larger variety device available
Computing power and sensor in environment
User with continuous online activities
Personal information and become impotant key
Need efficient storage, potable access rights

47. Database Security Challenges
Techniques for mobile users
Access control mechanisms + standar for id manage
Trust negotiation
Processing techniques for continuous queries

48. PART III Summary

49. Summary DB Security Concepts
Confidentialilty, Integrity and Avalaiblity
Database Sercurity Approaches
Access Control
Privacy-Preserving Data Techniques
Database Security Challenges
Data quality and Completeness
Access Control and Pravicy for Mobile users
Intellectual Property Right
Database survivability
Co so du lieu an toan phai bao dam 3 tinh chat: Bao mat, Toan Ven va san sang

50. References
[1] Database security-concepts, approaches, and challenges(2005)
[2] Ramez Elmasri and Shamkant B. Navathe Fundamentals of Database Systems”, 6th Edition (2010)

51. THANK YOU !

52. Questions
1. Why is the access control of information systems necessary?
A For the preservation of their authenticity, confidentiality, integrity and availability.
B For the preservation of their integrity and availability.
C For the preservation of their confidentiality and integrity.
D For the preservation of their authenticity, confidentiality and availability.
2. Which of the following best describes an access control mechanism in which access control decisions are based on the responsibilities that an individual user or process has in an organization?
A MAC (Mandatory Access Control)
B RBAC (Role Based Access Control)
C DAC (Discretionary Access Control)
D None of the above.

53. Answers 1. Why is the access control of information systems necessary?
A For the preservation of their authenticity, confidentiality, integrity and availability.
B For the preservation of their integrity and availability.
C For the preservation of their confidentiality, integrity.
D For the preservation of their authenticity, confidentiality and availability.
2. Which of the following best describes an access control mechanism in which access control decisions are based on the responsibilities that an individual user or process has in an organization?
A MAC (Mandatory Access Control)
B RBAC (Role Based Access Control)
C DAC (Discretionary Access Control)
D None of the above.