current trends in data security nursing research ppt

49
Current Trends in Data Security Dr. Jayesh Patidar www.drjayeshpatidar.blogspot.com

Upload: nursing-path

Post on 14-Apr-2017

406 views

Category:

Education


0 download

TRANSCRIPT

Page 1: Current trends in data security nursing research ppt

Current Trends in Data

Security

Dr. Jayesh Patidarwww.drjayeshpatidar.blogspot.com

Page 2: Current trends in data security nursing research ppt

2

Data Security

Dorothy Denning, 1982:

• Data Security is the science and study of

methods of protecting data (...) from

unauthorized disclosure and modification

• Data Security = Confidentiality + Integrity

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 3: Current trends in data security nursing research ppt

3

Data Security

• Distinct from systems and network security– Assumes these are already secure

• Tools:– Cryptography, information theory, statistics, …

• Applications:– An enabling technology

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 4: Current trends in data security nursing research ppt

4

Outline

• Traditional data security

• Two attacks

• Data security research today

• Conclusions

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 5: Current trends in data security nursing research ppt

5

Traditional Data Security

• Security in SQL = Access control +

Views

• Security in statistical databases =

Theory

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 6: Current trends in data security nursing research ppt

6

Access Control in SQL

GRANT privileges ON object TO users

[WITH GRANT OPTIONS]

privileges = SELECT | INSERT | DELETE | . . .

object = table | attribute

REVOKE privileges ON object FROM users

[CASCADE ]

[Griffith&Wade'76, Fagin'78]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 7: Current trends in data security nursing research ppt

7

Views in SQL

A SQL View = (almost) any SQL query

• Typically used as:

GRANT SELECT ON pmpStudents TO DavidRispoli

CREATE VIEW pmpStudents AS

SELECT * FROM Students WHERE…

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 8: Current trends in data security nursing research ppt

8

Summary of SQL Security

Limitations:

• No row level access control

• Table creator owns the data: that‟s unfair !

… or spectacular failure:

• Only 30% assign privileges to users/roles

– And then to protect entire tables, not columns

Access control = great success story of the DB community...

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 9: Current trends in data security nursing research ppt

9

Summary (cont)

• Most policies in middleware: slow, error

prone:

– SAP has 10**4 tables

– GTE over 10**5 attributes

– A brokerage house has 80,000 applications

– A US government entity thinks that it has 350K

• Today the database is not at the center of the

policy administration universe

[Rosenthal&Winslett‟2004]9/30/2015 www.drjayeshpatidar.blogspot.in

Page 10: Current trends in data security nursing research ppt

10

Security in Statistical DBs

Goal:

• Allow arbitrary aggregate SQL queries

• Hide confidential data

SELECT count(*)

FROM Patients�

WHERE age=42

and sex=„M‟

and diagnostic=„schizophrenia‟

OK

SELECT name

FROM Patient�

WHERE age=42

and sex=„M‟

and diagnostic=„schizophrenia‟

[Adam&Wortmann‟89]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 11: Current trends in data security nursing research ppt

11

Security in Statistical DBs

What has been tried:

• Query restriction– Query-size control, query-set overlap control, query

monitoring

– None is practical

• Data perturbation– Most popular: cell combination, cell suppression

– Other methods, for continuous attributes: may introduce bias

• Output perturbation– For continuous attributes only

[Adam&Wortmann‟89]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 12: Current trends in data security nursing research ppt

12

Summary on Security in

Statistical DB

• Original goal seems impossible to

achieve

• Cell combination/suppression are

popular, but do not allow arbitrary

queries

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 13: Current trends in data security nursing research ppt

13

Outline

• Traditional data security

• Two attacks

• Data security research today

• Conclusions

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 14: Current trends in data security nursing research ppt

14

Search claims by:

SQL InjectionYour health insurance company lets you see the claims online:

Now search through the claims :

Dr. Lee

First login: User:

Password:

fred

********

SELECT…FROM…WHERE doctor=„Dr. Lee‟ and patientID=„fred‟

[Chris Anley, Advanced SQL Injection In SQL]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 15: Current trends in data security nursing research ppt

15

SQL InjectionNow try this:

Search claims by: Dr. Lee‟ OR patientID = „suciu‟; --

Better:

Search claims by: Dr. Lee‟ OR 1 = 1; --

…..WHERE doctor=„Dr. Lee‟ OR patientID=„suciu‟; --‟ and patientID=„fred‟

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 16: Current trends in data security nursing research ppt

16

SQL InjectionWhen you‟re done, do this:

Search claims by: Dr. Lee‟; DROP TABLE Patients; --

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 17: Current trends in data security nursing research ppt

17

SQL Injection

• The DBMS works perfectly. So why is

SQL injection possible so often ?

• Quick answer:

– Poor programming: use stored procedures

!

• Deeper answer:

– Move policy implementation from apps to

DB9/30/2015 www.drjayeshpatidar.blogspot.in

Page 18: Current trends in data security nursing research ppt

18

Latanya Sweeney‟s Finding

• In Massachusetts, the Group Insurance

Commission (GIC) is responsible for

purchasing health insurance for state

employees

• GIC has to publish the data:

GIC(zip, dob, sex, diagnosis, procedure, ...)

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 19: Current trends in data security nursing research ppt

19

Latanya Sweeney‟s Finding

• Sweeney paid $20 and bought the voter

registration list for Cambridge

Massachusetts:

GIC(zip, dob, sex, diagnosis, procedure, ...)

VOTER(name, party, ..., zip, dob, sex)

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 20: Current trends in data security nursing research ppt

20

Latanya Sweeney‟s Finding

• William Weld (former governor) lives in

Cambridge, hence is in VOTER

• 6 people in VOTER share his dob

• only 3 of them were man (same sex)

• Weld was the only one in that zip

• Sweeney learned Weld‟s medical

records !

zip, dob, sex

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 21: Current trends in data security nursing research ppt

21

Latanya Sweeney‟s Finding

• All systems worked as specified, yet an

important data has leaked

• How do we protect against that ?

Some of today‟s research in data security address breaches

that happen even if all systems work correctly

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 22: Current trends in data security nursing research ppt

22

Summary on Attacks

SQL injection:

• A correctness problem:

– Security policy implemented poorly in the

application

Sweeney‟s finding:

• Beyond correctness:

– Leakage occurred when all systems work as

specified

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 23: Current trends in data security nursing research ppt

23

Outline

• Traditional data security

• Two attacks

• Data security research today

• Conclusions

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 24: Current trends in data security nursing research ppt

24

Research Topics in Data

Security

Rest of the talk:

• Information Leakage

• Privacy

• Fine-grained access control

• Data encryption

• Secure shared computation

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 25: Current trends in data security nursing research ppt

25

First Last Age Race

Harry Stone 34 Afr-Am

John Reyser 36 Cauc

Beatrice Stone 47 Afr-am

John Ramos 22 Hisp

First Last Age Race

* Stone 30-50 Afr-Am

John R* 20-40 *

* Stone 30-50 Afr-am

John R* 20-40 *

Information Leakage:

k-AnonymityDefinition: each tuple is equal to at least k-1 others

Anonymizing: through suppression and generalization

Hard: NP-complete for supression only

Approximations exists

[Samarati&Sweeney‟98, Meyerson&Williams‟04]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 26: Current trends in data security nursing research ppt

26

Information Leakage:

Query-view Security

Secret Query View(s)Disclosure

?

S(name) V(name,phone)S(name,phone)

V1(name,dept)

V2(dept,phone)

S(name) V(dept)

S(name)

where

dept=„HR‟

V(name)

where

dept=„RD‟

TABLE Employee(name, dept, phone)Have data:

total

big

tiny

none

[Miklau&S‟04, Miklau&Dalvi&S‟05,Yang&Li‟04]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 27: Current trends in data security nursing research ppt

27

Summary on Information

Disclosure

• The theoretical research:

– Exciting new connections between

databases and information theory,

probability theory, cryptography

• The applications:

– many years away

[Abadi&Warinschi‟05]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 28: Current trends in data security nursing research ppt

28

Privacy

• “Is the right of individuals to determine

for themselves when, how and to what

extent information about them is

communicated to others”

• More complex than confidentiality

[Agrawal‟03]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 29: Current trends in data security nursing research ppt

29

Privacy

Involves:

• Data

• Owner

• Requester

• Purpose

• Consent

Example: Alice gives her email

to a web service

[email protected]

Privacy policy: P3P

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 30: Current trends in data security nursing research ppt

30

Hippocratic Databases

DB support for implementing privacy

policies.

• Purpose specification

• Consent

• Limited use

• Limited retention

• …

[Agrawal‟03, LeFevrey‟04]

[email protected]

Privacy policy: P3P

Hippocratic DB

Protection against:

Sloppy organizations

Malicious organizations9/30/2015 www.drjayeshpatidar.blogspot.in

Page 31: Current trends in data security nursing research ppt

31

Privacy for Paranoids

• Idea: rely on trusted agents

[email protected]

Agent

[email protected]

[email protected]

foreign keys ?

[Aggarwal‟04]

Protection against:

Sloppy organizations

Malicious attackers9/30/2015 www.drjayeshpatidar.blogspot.in

Page 32: Current trends in data security nursing research ppt

32

Summary on Privacy

• Major concern in industry

– Legislation

– Consumer demand

• Challenge:

– How to enforce an organization‟s stated

policies

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 33: Current trends in data security nursing research ppt

33

Fine-grained Access Control

Control access at the tuple level.

• Policy specification languages

• Implementation

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 34: Current trends in data security nursing research ppt

34

Policy Specification Language

CREATE AUTHORIZATION VIEW PatientsForDoctors AS

SELECT Patient.*

FROM Patient, Doctor

WHERE Patient.doctorID = Doctor.ID

and Doctor.login = %currentUser

Context

parameters

No standard, but usually based on parameterized views.

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 35: Current trends in data security nursing research ppt

35

ImplementationSELECT Patient.name, Patient.age

FROM Patient

WHERE Patient.disease = „flu‟

SELECT Patient.name, Patient.age

FROM Patient, Doctor

WHERE Patient.disease = „flu‟

and Patient.doctorID = Doctor.ID

and Patient.login = %currentUser

e.g. Oracle

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 36: Current trends in data security nursing research ppt

36

Two Semantics

• The Truman Model = filter semantics– transform reality

– ACCEPT all queries

– REWRITE queries

– Sometimes misleading results

• The non-Truman model = deny semantics– reject queries

– ACCEPT or REJECT queries

– Execute query UNCHANGED

– May define multiple security views for a user[Rizvi‟04]

SELECT count(*)

FROM Patients

WHERE disease=„flu‟

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 37: Current trends in data security nursing research ppt

37

Summary of Fine Grained

Access Control• Trend in industry: label-based security

• Killer app: application hosting

– Independent franchises share a single table at headquarters (e.g., Holiday Inn)

– Application runs under requester‟s label, cannot see other labels

– Headquarters runs Read queries over them

• Oracle‟s Virtual Private Database

[Rosenthal&Winslett‟2004]9/30/2015 www.drjayeshpatidar.blogspot.in

Page 38: Current trends in data security nursing research ppt

38

Data Encryption for Publishing

• Users and their keys:

• Complex Policies:

All authorized users: Kuser

Patient: Kpat

Doctor: Kdr

Nurse: Knu

Administrator : Kadmin

What is the encryption granularity ?

Doctor researchers may access trials

Nurses may access diagnostic

Etc…

Scientist wants to publish

medical research data on the Web

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 39: Current trends in data security nursing research ppt

39

Data Encryption for PublishingAn XML tree protection:

<patient>

<privateData>

<name> <age>

<diagnostic>

JoeDoe 28

<address>

Seattle

<trial>

<drug>

flu

<placebo>

Kuser

Kpat (Knu Kadm) Knu KdrKdr

Kpat Kmaster Kmaster

Tylenol Candy

[Miklau&S.‟03]

Doctor: Kuser, Kdr

Nurse: Kuser, Knu

Nurse+admin: Kuser, Knu, Kadm

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 40: Current trends in data security nursing research ppt

40

Summary on Data Encryption

• Industry:

– Supported by all vendors:

Oracle, DB2, SQL-Server

– Efficiency issues still largely unresolved

• Research:

– Hard theoretical security analysis[Abadi&Warinschi‟05]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 41: Current trends in data security nursing research ppt

41

Secure Shared Processing

• Alice has a database DBA

• Bob has a database DBB

• How can they compute Q(DBA, DBB), without

revealing their data ?

• Long history in cryptography

• Some database queries are easier than

general case9/30/2015 www.drjayeshpatidar.blogspot.in

Page 42: Current trends in data security nursing research ppt

42

Secure Shared Processing

[Agrawal‟03]

Alice Bob

a b c d c d e

h(a) h(b) h(c) h(d) h(c) h(d) h(e)

Compute one-way hash

Exchange

h(c) h(d) h(e) h(a) h(b) h(c) h(d)

What‟s wrong ?

Task: find intersection

without revealing the rest

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 43: Current trends in data security nursing research ppt

43

Secure Shared ProcessingAlice Bob

a b c d c d e

EB(c) EB(d) EB(e) EA(a) EA(b) EA(c) EA(d)

commutative encryption:h(x) = EA(EB(x)) = EB(EA(x))

EA(a) EA(b) EA(c) EA(d) EB(c) EB(d) EB(e)

EA EB

h(c) h(d) h(e) h(a) h(b) h(c) h(d)

EA EB

h(a) h(b) h(c) h(d) h(c) h(d) h(e)

[Agrawal‟03]

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 44: Current trends in data security nursing research ppt

44

Summary on Secure Shared

Processing

• Secure intersection, joins, data mining

• But are there other examples ?

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 45: Current trends in data security nursing research ppt

45

Outline

• Traditional data security

• Two attacks

• Data security research today

• Conclusions

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 46: Current trends in data security nursing research ppt

46

Conclusions

• Traditional data security confined to one

server

– Security in SQL

– Security in statistical databases

• Attacks possible due to:

– Poor implementation of security policies: SQL

injection

– Unintended information leakage in published data

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 47: Current trends in data security nursing research ppt

47

Conclusions

• State of the industry: – Data security policies: scattered throughout applications

– Database no longer center of the security universe

– Needed: automatic means to translate complex policies into physical implementations

• State of research: data security in global data sharing– Information leakage, privacy, secure computations, etc.

– Database research community has an increased appetite for cryptographic techniques

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 48: Current trends in data security nursing research ppt

48

Questions ?

9/30/2015 www.drjayeshpatidar.blogspot.in

Page 49: Current trends in data security nursing research ppt

Thank You

499/30/2015 www.drjayeshpatidar.blogspot.in