Full Disclosure mailing list archives
Re: Cisco IOS Shellcode Presentation
From: Valdis.Kletnieks () vt edu
Date: Fri, 29 Jul 2005 22:12:39 -0400
On Fri, 29 Jul 2005 15:02:51 -1000, Jason Coombs said:
There are any number of technical solutions that one could use to redesign, fundamentally, the turing machine so that before each operation is performed a verification step is employed to ensure that the operation is the correct one in the correct sequence given prior configuration settings loaded into memory at the time the device was activated.
Ahem. No. You *can't* "ensure" it (although you *can* do things like bounds checking to *minimize* issues). It's called the Turing Halting Problem, and in fact, the 'Turing machine' was invented specifically to (a) show the problem for that simple architecture, and then (b) show that all Turing-equivalent systems have the exact same problem.
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Current thread:
- Re: Cisco IOS Shellcode Presentation, (continued)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation Randall Perry (Jul 29)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation Jochen Kaiser (Jul 29)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation J.A. Terranson (Jul 29)
- Re: Cisco IOS Shellcode Presentation Frank Knobbe (Jul 29)
- Re: Cisco IOS Shellcode Presentation Andrew R. Reiter (Jul 29)
- Re: Cisco IOS Shellcode Presentation J.A. Terranson (Jul 29)
- Re: Cisco IOS Shellcode Presentation Jason Coombs (Jul 29)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation Jason Coombs (Jul 29)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation lsi (Jul 30)
- Re: Cisco IOS Shellcode Presentation Valdis . Kletnieks (Jul 29)
- Re: Cisco IOS Shellcode Presentation J.A. Terranson (Jul 29)
- RE: Cisco IOS Shellcode Presentation Geo. (Jul 29)
- Re: Cisco IOS Shellcode Presentation Jason (Jul 29)
- Re: Cisco IOS Shellcode Presentation Pavel Kankovsky (Jul 30)
- Re: Cisco IOS Shellcode Presentation Ron DuFresne (Jul 29)