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Saturday, September 04, 2004 14:00 // SUCON'04, Technopark, Zurich, Switzerland // href
by Amon Ott
Why
Classic Access Control is not sufficient to define secure access scenarios:
The granularity is way too small (only user group read write execute)
Every user can decide the access permissins for his files.
root can do everything
Solution
Other models (not one, but several appropriate ones) are required for describing security policies according to the requirements of the project.
RSBAC is a framework for implementing access control systems.
It can control individual users and programs as well as incoming and outgoing network connections.
The first stable version has been released in March 2000.
RSBAC can be extended with loadable modules.
Auditing and logging is supported at every level.
Architecture
Subjects - are processes acting on behalf of a user.
Object Types - like FILE, DIR, PROCESS, USERS, NETDEV, ...
Requests - abstraction of what the a subject wants to-do with an object. (eg. R_LINK_HARD, ...)
RSBAC acts on system calls. When a system call is received, the call gets intercepted and passed on to the decision-making facility where a decision is taken if the system call should be performed or not. Once a system call is performed a notification is generated so that the access control system knows what is happening and can take this into account for further decisions.
Models
RSBAC supports number of different access control models.
AUTH - Can be used to restrict which UIDS a process can change to.
Role Compatibiliti (RC) - Subjects and objects are sorted into roles and object types. The rules are then described based on the roles and object types. This makes simple to keep rules stable even though users and objects change.
ACLs - Who may access which object with which rights. RC Roles can be used in this.
File Flags (FF) - Secure Delete, Append Only.
Linux Capabilities (CAP) - lets you control normal Linux capabilities from outside the process.
Process Jails (JAIL) - Like BSD Jails (the better chroot)
Resource Control (RES) - File size, Memory, CPU time, ...
Pageexec (PAX) - anti stack smashing ...
How to get it
Kernel patch from www.rsbac.org
Test ist with the iso images from (www.adamantix.org ...)
Quote
The basic idea of RSBAC is to introduce a second level of security to make sure that errors and mistakes one makes in the first level do not lead to disaster.
Saturday, September 04, 2004 15:01 // SUCON'04, Technopark, Zurich, Switzerland // href
by Fredy Künzler
Things I learned
There is no money in ADSL. Swisscom expects the market to be saturated next year.
In summer 2005 Swisscom will offer SDSL (probably 2mb symertical) everywhere. It will be over-booked and not guaranteed availability.
SDSL is like ADSL but without Voice Line on the same wire.
Bluewin 40 million loss per year.
Sunrise can only survive because of their GSM license.
There is no Money in ADSL
End user pays CHF 45.55 (+VAT)
Provider pays CHF 31.20 for the ADSL link to Swisscom. In addition to this the provider has to pay for the network bandwidth between his network and the ADSL backbone (backhaul) this cost CHF 391 for 1 Megabit/s per Month. With moderate overbooking he can fit 40 ADSL customers into one Megabit. This adds another CHF 10 for each of his cutomers.
This means at the end of the day the ISP gets about 4 CHF per ADSL link and month.
The normal wholesale price for 1 Megabit/s connectivity is CHF 100 per Month.
Whats worse, in spring 2003 WEKO got Swisscom to lower the prices they charge for ADSL connectivity by 20%. Swisscom is fighting this decision in court. If they winn, all ISP will have to back the 'missing' 20% back to Swisscom. This will cause a great many of them to go out of buisness.
Content © by Tobias Oetiker