hexatier - mysql role-based security & data masking

©2002-2016 Teladoc, Inc. All rights reserved.

Hexatier at Teladoc9/8/2016

©2002-2016 Teladoc, Inc. All rights reserved.2

Hexatier Architecture

• Hexatier is a network proxy process running on a Linux server, designed to receive and forward MySQL database connections

• Applications and MySQL clients see the proxy as a MySQL database. Hexatier receives the connections, applies rules and passes approved connections and queries on to the database


Hexatier Architecture

AppServers

Desktops

HexatierProxy

(10.240.20.100)

MySQLDatabase

AppServers

Desktops

HexatierProxy

(10.240.20.100)

MySQLDatabase

X

Note – As MySQL database accounts can be configured to include a host address, the architecture can be designed to ensure the proxy cannot be bypassed. All traffic will be subject to Hexatier authority.


Hexatier Capabilities

Hexatier offers three security capabilities in current use at Teladoc ;

• Table Access Control

• Data Masking

• Activity Auditing


Table Access Control

• Hexatier allows users and groups of users to have access only to assigned tables.

• Privileges are managed via a series of rules, applied in a top-down manner to each data request.

• MySQL privilege grants offer similar capability, but are managed only at the user level.

• Hexatier’s use of rules and user-groups allows a form of role-based security to operate, greatly simplifying security management.


Table Access Control – Users on MySQL

Corresponding Users on Database:

• Users are created on the database with full privileges, relying on Hexatier to apply security.• This is secure as access is allowed ONLY through Hexatier proxy’s IP address (10.240.20.100)


Table Access Control – Users on Hexatier

Users (inherited from database) :

Users Groups (can contain users or other user groups) :


Table Access Control - Policies

• Ordering of rules is important, most restrictive at the bottom to catch “none of the above” and block all access. People with no rules assigned have no access.

• Grantee’s can be individual users or pre-defined groups of users ( roles ! )

Policies define table access rules


Table Access Control – Policy Contents

Contents of a Policy :

Users affected by policy

Restrictions can be database, table or column-based

Allowed privileges

Log violations?


Table Access Control - Example using “nyug1”

User “nyug1” defined on database Usergroup “dw_NYUG_members” created, user “nyug1” added to group

Usergroup “dw_demo_hexatier_ro” created, user “dw_NYUG_members” added to group Note – Up to this point Hexatier

is authorizing no privileges, user “nyug1” has no privs on the database. Usergroups are just logical constructions.


Table Access Control – Policy Example

Goal – set up policy allowing select on database “demo_hexatier”

Who

What

Privs


Table Access ControlExample using nyug1, effect of policy ;

1) Can see data in database “demo_hexatier”

2) No rows returned when querying database “DW“

3) Unable to update data in database “demo_hexatier”


What We’ve Just Done

13

Created user

nyug1

Created logical group of users

dw_NYUG_members

Created group to relate policies to user-groups

dw_demo_hexatier_ro

Created policy to define rules

dw_demo_hexatier_ro

Database

demo_hexatier

Users can be easily moved between user-groups

User-groups can be moved between policies

= Role-Based Security


Table Access Control – New Role for DMLCreate new user group to hold users allowed DML

Create new policy allowing DML, assign above user group to it


What We’ve Just Done

15

dw_NYUG_members dw_demo_hexatier_ro dw_demo_hexatier_ro demo_hexatier

dw_WashDC_members

Moving users between groups, groups between rules

dw_demo_hexatier_rw dw_demo_hexatier_rw


Data Masking

• Proxy holds rules describing which tables and columns should have data masked before being returned to client.

• Rules can be configured and granted dynamically.

• Different rules can apply to different users & user-groups.

• Data remains in the clear within database.


Data MaskingRule below instructs proxy to mask “first_nm”, “last_nm”, “user_nm” and “ssn” from role “dw_NYU_members;

If the data-types of the columns being masked by the policy are the same, there is great flexibility in how they are masked.


Effect of Data Masking on “nyug1”

Designated columns masked for “nyug1”

Masked tables remain join-able


Activity Auditing

• Each table access control rule can be set to write audit records each time it is invoked.

• Each data masking rule can be set to write audit records each time it is invoked.

• As each security installation will contain a rule to deny access to any query not matching a granting rule, auditing this rule records all attempts to access prohibited data.


Activity Auditing

Audit Record of a Policy Violation :


Performance Benchmarking

Industry-standard TPCC benchmarks were run against the Hexatier POC deployment with the following feature combinations enabled;

1. Baseline (proxy bypassed)2. Hexatier controling table access3. Hexatier access control and PHI masking4. Hexatier access control, PHI masking & full

transaction logging


Performance Benchmarking

System Details• Database

– AWS RDS MySQL, m3xlarge (4 CPU, 15GB ram, prov io ssd)

• Proxy Server– AWS EC2 Centos, m4large (2 CPU, 8GB ram, prov io ssd)

# Virtual Users

Transactions Per Minute

10 20 30 40 50 60 70 80 90 1000

100000

200000

300000

400000

500000

600000

700000

800000

900000

1000000

Baseline, Proxy BypassedProxy, Table Access Control, No MaskingProxy, Table Access Control, PHI MaskingProxy, Table Access Control, PHI Masking, all transactions logged

Note : Teladoc’s production database db1a.us1 averages approx. 35,000 TpM during business hours


Features in Hexatier not in use currently at Teladoc

23

Can’t speak knowledgably of these, but mentioning anyway;

• Access via query-groups• Queries can be tracked and “learned” over a given period.• Once all common queries have been learned, queries outside of this set can

be either prohibited or reported.

• Access limited by ip address• Any policy can be set to allow access from specific ip addresses only.• Similar limits possible for known applications, schedules, etc…

• Injection attack detection & reporting

hexatier - mysql role-based security & data masking

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