Chapter 4 Access Control Manage Principals operations in system

Resources Access control Which principals have access to what resources on the system and when Applications Middleware Operating system Hardware

Access control system System authenticates principal using some method, then controls access to system resources. Often a matrix of permissions Triple of User Program File See matrix page 53 Matrices grow very large Control this through groups or roles Certificated based systems coming about I have a certificate signed by some authority that I have a specific right.

Groups and roles Do not assign rights individually Assign to groups that represents the activities or job titles of employees They define the rules, you implement them ACL Access Control List Column of the matrix who has what rights to resource

UNIX Root can access everything. Not a good thing, even system admin should not have access to certain files: Audit trails Logs Newer versions of UNIX have worked to separate out these duties Military versions even more so

Granularity Security and Database Database is 1 file so OS must give access to this one file Within in the database security is controlled by the DBMS This creates various issues with passwords, management and control Many systems, many passwords Companies striving for 1 central directory service This is why Microsoft wants it’s Active Directory product to become a “standard”

Sandboxing Java uses this Applet runs in a virtual restricted environment Does not have access to hard drive JVM has limited local access

Object Request Brokers Mediates communications between objects Outgrowth of Object Oriented programming Common Object Request Broker Architecture (CORBA) Industry standard

Hardware protection Protect one process from interfering with another Memory Metadata (data about processes) Hardware access control Rings of protection Less privileged process (user program) needs to access more privileged process (device driver)

Processors Intel processors page 63 ARM processors page 63 Security processors page 64 QoS Quality of Service issues. One process does not hog CPU

What goes wrong Smashing the stack Syn flooding Trojan horse Root kits Single commands Full root kits Active web content And many more programming defects

NSA Deep distrust of application security Heavy emphasis on trusted OS security

Environmental creep UNIX original use was in trusted environment Todays use is in the most untrusted environment (internet) Many tools also develop for trusted environment FTP, SMTP, DNS… Used in most untrusted environment Code used to be buggy, now is malicious Script kiddies anyone can attack system

Discussion topics Current stack smashing article Environment Creep and OS attacks Current state of windows root kit Where should security lie? OS, applications, middleware? Certificate based security.

Articles Root Kit articles: m/originalContent/0,289142,sid45_gci ,00.html m/originalContent/0,289142,sid45_gci ,00.html

List of resources Access control l l Groups roles tures/accesscntrl.mspx tures/accesscntrl.mspx rbac.shtml rbac.shtml brary/72b cc-4c7f-8fbf cd0b61033.mspx brary/72b cc-4c7f-8fbf cd0b61033.mspx

List of resources Sandboxing curity/sandboxing.html curity/sandboxing.html m m

List of resources Object Request Brokers broker broker a_body.html a_body.html Rings

List of Resources NSA