Lecture Database security and auditing - Protecting data integrity and accessibility - Chapter 8: Application Data Auditing

Database Security and
Auditing: Protecting Data
Integrity and Accessibility
Chapter 8
Application Data Auditing


Objectives

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Understand the difference between the auditing
architecture of DML Action Auditing Architecture
and DML changes
Create and implement Oracle triggers
Create and implement SQL Server triggers
Define and implement Oracle fine-grained
auditing

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Objectives (continued)

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Create a DML statement audit trail for Oracle
and SQL Server
Generate a data manipulation history
Implement a DML statement auditing using a
repository

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Objectives (continued)

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Understand the importance and the
implementation of application errors auditing in
Oracle
Implement Oracle PL/SQL procedure
authorization

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DML Action Auditing Architecture

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Data Manipulation Language (DML): companies
use auditing architecture for DML changes
DML changes can be performed on two levels:
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Row level
Column level

Fine-grained auditing (FGA)

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DML Action Auditing Architecture
(continued)

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DML Action Auditing Architecture
(continued)

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Oracle Triggers

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Stored PL/SQL procedure executed whenever:
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DML operation occurs
Specific database event occurs

Six DML events (trigger timings): INSERT,
UPDATE, and DELETE
Purposes:

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Audits, controlling invalid data
Implementing business rules, generating values

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Oracle Triggers (continued)

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Oracle Triggers (continued)
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CREATE TRIGGER
Executed in a specific order:
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STATEMENT LEVEL triggers before COLUMN
LEVEL triggers
BEFORE triggers before AFTER triggers

USER_TRIGGERS data dictionary view: all
triggers created on a table
A table can have unlimited triggers: do not
overuse them
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Oracle Triggers (continued)

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SQL Server Triggers

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CREATE TRIGGER DDL statement: creates a
trigger
Trigger condition:

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Prevents a trigger from firing
UPDATE() and COLUMNS_UPDATE() functions

Logical tables:
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DELETED contains original data
INSERTED contains new data

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SQL Server Triggers (continued)
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Restrictions—Transact-SQL statements not
allowed:
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ALTER and CREATE DATABASE
DISK INIT and DISK RESIZE
DROP DATABASE and LOAD DATABASE
LOAD LOG
RECONFIGURE
RESTORE DATABASE
RESTORE LOG

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Implementation of an Historical Model
with SQL Server
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Create a history table:
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Same structure as original table
HISTORY_ID column

Create a trigger: inserts original row into the

HISTORY table

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Fine-grained Auditing (FGA) with
Oracle
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Oracle provides column-level auditing: Oracle
PL/SQL-supplied package DBMS_FGA
DBMS_FGA procedures:
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ADD_POLICY
DISABLE_POLICY
DROP_POLICY
ENABLE_POLICY

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Fine-grained Auditing (FGA) with
Oracle (continued)
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ADD_POLICY parameters:
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OBJECT_SCHEMA
OBJECT_NAME
POLICY_NAME
AUDIT_CONDITION
AUDIT_COLUMN
HANDLER_SCHEMA

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Fine-grained Auditing (FGA) with
Oracle (continued)
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ADD_POLICY parameters (continued):

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HANDLER_MODULE
ENABLE
STATEMENT_TYPES

DBA_FGA_AUDIT_TRAIL: view the audit trail
of the DML activities

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DML Action Auditing with Oracle

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Record data changes on the table:
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Name of the person making the change

Date of the change
Time of the change

Before or after value of the columns are not
recorded

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DML Action Auditing with Oracle
(continued)

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DML Action Auditing with Oracle
(continued)
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Steps:
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Use any user other than SYSTEM or SYS; with
privileges to create tables, sequences, and
triggers
Create the auditing table
Create a sequence object
Create the trigger that will record DML
operations
Test your implementation

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History Auditing Model Implementation
Using Oracle
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Historical data auditing is simple to implement;
main components are TRIGGER objects and
TABLE objects
Keeps record of:
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Date and time the copy of the record was
captured

Type of operation applied to the record

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History Auditing Model Implementation
Using Oracle (continued)
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Steps:
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Use any user other than SYSTEM or SYS; with
privileges to create tables, sequences, and
triggers
Create history table
Create the trigger to track changes and record
all the values of the columns
Test your implementation

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DML Auditing Using Repository with
Oracle (Simple 1)
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Simple Auditing Model 1
Flag users, tables, or columns for auditing
Requires less database administrative skills:
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Application administrators can do it
User interface is built in top of the repository

Auditing flags are flexible
Does not record before or after column values;
only registers type of DML operations

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DML Auditing Using Repository with
Oracle (Simple 1) (continued)

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DML Auditing Using Repository with
Oracle (Simple 1) (continued)
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Steps:
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Use any user other than SYSTEM or SYS
Create triggers
Create sequence object
Build tables to use for applications
Populate application tables

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