Access Control in GAIA Operating

System

GAIA • OS for ubiquitous system.

• Built at middle-ware level built over native participating OS

• It has a context aware file system

• Each file is encapsulated in a container

• Each file has some context variables defined for it.

<CFS:Storage>

<CFS:Owner>Munawar</CFS:Owner>

<CFS:Host>srg181</CFS:Host>

<CFS:Path>c:\Temp\15687</CFS:Path>

<CFS:Context>

<CFS:Type>situation</CFS:Type>

<CFS:Value>class-presentation</CFS:Value>

</CFS:Context>

<CFS:Context>

<CFS:Type>location</CFS:Type>

<CFS:Value>106B1-Engg Hall</CFS:Value>

</CFS:Context>

</CFS:Storage>

Context File System of GAIA

Problem Statement

Implement cryptographic access control for GAIA's Context File System.

General problem of cryptographic access control

Identifying the User making the request

The whole problem is a jigsaw puzzle and it’s a

matter of putting the pieces in the right position

And make correct decisions to get the whole solution.

Client Side Support

At this point all users make request as root while accessing files.

So, the client side CORBA interceptor should have amechanism of including the user ID with every file accessrequest.

Decision 1 – Add user ID with everyFile access request.

Communication between client-server shouldbe secure

We would use OpenSSH for crypto solution and some key-generation protocol for sessionkey management.

An existing protocol like Otway-Rees wouldbe used.

Maintaining the Access Control List

Add an additional field to the XML definition for each file

<CFS:Privilege>rwxr—r-x</CFS:Privilege>

Looks a Lot like UNIX !!!!!!!

We have to implement some user and group management scheme like UNIX.

File Access Policies

Clients have different nativeOS – therefore the files shouldundergo filtering before being sent to clients.

A filtering mechanism is already existent – Some augmentation may be necessary.

Credentials

GAIA AS provides credentials

Jalal is working on this. We would be using his component

Everything in middleware

Current Activities

•Creating a draft of design•Going through the code•And a lot of reading materials, ,phew…

Almost left anImportant point

Where are we putting the privilege information and how do we secure it?

Suggestions and Questions ??