hummmm, i would beg to differ with the 'iamdrscience' post. You are thinking about normal computer science hashes not cryptographic hashes.
207 billion is a very small portion of the possible hash relations.
I worked on a project similar to this, a distributed password cracker.
They calculated 50million passwords and 4096 salts this gives ~207Billion hashes.
There are ~7.32*10^14 possible passwords (quick approximation) with the 4096 possible salts. That gives ~2.99*10^18 possible hashes.
I think the author of the other post was thinking there would be a lot of collisions. There are 2^64 possible permutations of the DES 'cipher text' which gives ~1.8*10^19 possible 'cipher text' final state.
This means there are six times as many theoretical hashes as there are actual password hashes. That and the nature of the DES algorithm would make colusion not very likely.
Anyway back to the point... 207 billion hashes would be 2.07*10^11.
2.07*10^11/2.99*10^18 =.000007%
This is NOT a substantial portion of the search space.
-Nick
*cipher text is refering to the initial 64 zeros cipher text used in the DES password encryption.
This is something that has bothered me about crypto phones in the past.
Key verification usually isn't handeled all that well on mobile devices.
From reading the pdf and making some logic leaps this is how i think they handle key verification:
Looking at the DH to encrypted data tree, the DH key gets hashed broken up and passed off to be the AES key, the twofish key and to the user. There is a little user picture and the key is heading to the user! hummm, interesting.
So the user gets to see part of hash, then what?
On the larger phone images you can clearly see a "you say: XXX" and "partner say: XXX"...
It seems that the user would read off a sort of challenge and responce for the key (text not hex), which i _hope_ would scroll on to show a lot more charecters. I would also guess that it probably is based of hash that 'goes' to each user.
The crypto scheme doesn't seem to have any capabilites for signing the DH key. The DH key changes every time a phone call is made. This leaves me with only one conclusion, the user has to read off the string every time.
This seems to be a large user interface weakness with the phone, as most user would get very tired of reading off a number of phrases before starting each phone call... or perhaps even worse the DH key is hashed into only six chars.
Well, I could be completely off base...or then again not.
-Nick
I would expect an article like this from Tom's Hardware, not from IBM developerWorks.
Sticking together an embedded board with an 802.11b card and a bit of flash memory is hardly a challenge. This belongs on CNET not/.
I made something similar seven years ago! Using an old 486 and a WebGear Aviator 2.4 (pre 802.11b) card. The only difference he was using CF for the operating system! WOW that's amazing! I had to scrounge together the drivers for my system, and spend days searching for helpful documentation.
Very long, but worth the time to read. I've been a big fan of Schneier since i read his book a few years ago.
Best Article quote:
"Cryptophiles, Schneier among them, had been so enraptured by the possibilities of uncrackable ciphers that they forgot they were living in a world in which people can't program VCRs.
Perfect timing as I'm gearing up for CRYPTO 2002 at UCSB, YAY!
Last time i tried Ximian (a month or two ago) it was a nice clean interface, and for the most part Red Carpet was happy to update my programs and install new ones.
From time to time, everything i tried to update would fail the checksum test, but that might have been a bad server.Other times it would deny the existence of programs it had updated before.
Unfortunately the install proccess wasn't pretty, it insisted on downloading all the temporary install files to/var, and couldn't be persuaded to put them anywhere else. This was quite a pain when your/var directory is only 200MB.
Overall, i enjoyed Ximian but it is far better than regular Gnome, but it does have some flaws which need to be fixed...
Couldn't even see the website, firewall too sceureCouldn't even see the website, the firewall is too sceure..
SecureIIS application firewall security alert
HTTP Request caused a security alert, please contact our web master if you are getting this alert in error.
What is SecureIIS
SecureIIS offers websites running Microsoft Internet Information Server a broad range of protection from common vulnerabilities, both known and unknown. Because SecureIIS does not protect against specific vulnerabilities, but classes of vulnerabilities, it allows for a much more far reaching layer of security.
"www.nokia.com is temporarily off-line for scheduled maintenance.
www.nokia.com will return by Thursday evening, January 18 2001."
What interesting timing!
Right after they got slashdotted.
        -MB
Slashdot Mirror
hummmm, i would beg to differ with the 'iamdrscience' post.
.000007%
You are thinking about normal computer science hashes not cryptographic hashes.
207 billion is a very small portion of the possible hash relations.
I worked on a project similar to this, a distributed password cracker.
They calculated 50million passwords and 4096 salts this gives ~207Billion hashes.
There are ~7.32*10^14 possible passwords (quick approximation) with the 4096 possible salts.
That gives ~2.99*10^18 possible hashes.
I think the author of the other post was thinking there would be a lot of collisions.
There are 2^64 possible permutations of the DES 'cipher text' which gives ~1.8*10^19 possible 'cipher text' final state.
This means there are six times as many theoretical hashes as there are actual password hashes.
That and the nature of the DES algorithm would make colusion not very likely.
Anyway back to the point... 207 billion hashes would be 2.07*10^11.
2.07*10^11/2.99*10^18 =
This is NOT a substantial portion of the search space.
-Nick
*cipher text is refering to the initial 64 zeros cipher text used in the DES password encryption.
Key verification usually isn't handeled all that well on mobile devices.
From reading the pdf and making some logic leaps this is how i think they handle key verification:
Looking at the DH to encrypted data tree, the DH key gets hashed broken up and passed off to be the AES key, the twofish key and to the user. There is a little user picture and the key is heading to the user!
hummm, interesting.
So the user gets to see part of hash, then what?
On the larger phone images you can clearly see a "you say: XXX" and "partner say: XXX"...
It seems that the user would read off a sort of challenge and responce for the key (text not hex), which i _hope_ would scroll on to show a lot more charecters. I would also guess that it probably is based of hash that 'goes' to each user.
The crypto scheme doesn't seem to have any capabilites for signing the DH key. The DH key changes every time a phone call is made. This leaves me with only one conclusion, the user has to read off the string every time.
This seems to be a large user interface weakness with the phone, as most user would get very tired of reading off a number of phrases before starting each phone call... or perhaps even worse the DH key is hashed into only six chars.
Well, I could be completely off base...or then again not.
-Nick
I would expect an article like this from Tom's Hardware, not from IBM developerWorks.
/.
Sticking together an embedded board with an 802.11b card and a bit of flash memory is hardly a challenge. This belongs on CNET not
I made something similar seven years ago! Using an old 486 and a WebGear Aviator 2.4 (pre 802.11b) card. The only difference he was using CF for the operating system! WOW that's amazing! I had to scrounge together the drivers for my system, and spend days searching for helpful documentation.
This article is a joke.
-Nick
Boo Jason!
Anoymous Coward don't work for the nexus they pay shit.
"I'm the Online Editor for the Daily Nexus", Online Editor, what's that?
Everyone knows you're the nexus bitch....
-Nick (your neighbor)
No It's not a Hoax, i read it in the campus newspaper on friday.
Need more authentication than that? read my past posts.
Yes, one of the *nix users could set their box up to forward packets for their friends, but it probably won't happen on a large scale.
-Nick
Lex Systems
Its tiny, powerfull, and has tripple ethernet... what more could you ask for?
well maybe a fanless cpu.
-Nick
now if i can only find somewhere that sells it....
Well of course, H4X0RZ never make mistakes...
-NickVery long, but worth the time to read. I've been a big fan of Schneier since i read his book a few years ago.
Best Article quote: "Cryptophiles, Schneier among them, had been so enraptured by the possibilities of uncrackable ciphers that they forgot they were living in a world in which people can't program VCRs.
Perfect timing as I'm gearing up for CRYPTO 2002 at UCSB, YAY!
-Nick
Last time i tried Ximian (a month or two ago) it was a nice clean interface, and for the most part Red Carpet was happy to update my programs and install new ones.
/var, and couldn't be persuaded to put them anywhere else. This was quite a pain when your /var directory is only 200MB.
From time to time, everything i tried to update would fail the checksum test, but that might have been a bad server.Other times it would deny the existence of programs it had updated before.
Unfortunately the install proccess wasn't pretty, it insisted on downloading all the temporary install files to
Overall, i enjoyed Ximian but it is far better than regular Gnome, but it does have some flaws which need to be fixed...
-Nick
CDC wouldn't know what to do with root passwords.
Only a couple of the companies have disappeared, e.g. Atari, Pan Am.
Others like Coca Cola aren't in any imminent danger of going bankrupt.
SecureIIS application firewall security alert
HTTP Request caused a security alert, please contact our web master if you are getting this alert in error.
What is SecureIIS SecureIIS offers websites running Microsoft Internet Information Server a broad range of protection from common vulnerabilities, both known and unknown. Because SecureIIS does not protect against specific vulnerabilities, but classes of vulnerabilities, it allows for a much more far reaching layer of security.
eEye? Digital Security - Vulnerability Is Over...
Don't forget space.com
"www.nokia.com is temporarily off-line for scheduled maintenance.
www.nokia.com will return by Thursday evening, January 18 2001."
What interesting timing!
Right after they got slashdotted.
        -MB