Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread John Denker
I don't have any hard information or even any speculation about BULLRUN, but I have an observation and a question: Traditionally it has been very hard to exploit a break without giving away the fact that you've broken in. So there are two fairly impressive parts to the recent reports: (a)

Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread Perry E. Metzger
On Thu, 05 Sep 2013 16:56:38 -0700 John Denker j...@av8n.com wrote: The generator can be easily tested for correct behavior if it is simply a block cipher. I wouldn't have said that. As Dykstra was fond of saying: Testing can show the presence of bugs; testing can never show

Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread Peter Gutmann
John Denker j...@av8n.com writes: To say the same thing the other way, I was always amazed that the Nazis were unable to figure out that their crypto was broken during WWII. There were experiments they could have done, such as sending out a few U-boats under strict radio silence and comparing

Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread Phillip Hallam-Baker
Sent from my difference engine On Sep 5, 2013, at 9:22 PM, Peter Gutmann pgut...@cs.auckland.ac.nz wrote: John Denker j...@av8n.com writes: To say the same thing the other way, I was always amazed that the Nazis were unable to figure out that their crypto was broken during WWII. There were

Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread Richard Clayton
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 In message 52291a36.9070...@av8n.com, John Denker j...@av8n.com writes To say the same thing the other way, I was always amazed that the Nazis were unable to figure out that their crypto was broken during WWII. There were experiments they could

Re: [Cryptography] tamper-evident crypto? (was: BULLRUN)

2013-09-05 Thread Charles Jackson
On Thu, Sep 5, 2013 at 9:18 PM, Peter Gutmann pgut...@cs.auckland.ac.nzwrote: To say the same thing the other way, I was always amazed that the Nazis were unable to figure out that their crypto was broken during WWII. There were experiments they could have done, such as sending out a few