You are here

rick's blog

Spying as public activity

Critics and comics sometimes say that government insiders get more accurate information from CNN than from the CIA. Now we have 'open source spying' (Wall Street Journal). There's a grad student who, via his "North Korea Uncovered" web site, is documenting all sorts of details of that notoriously secretive country.
Post category: 

Matlab, RC4, and Crypto-Graphics

A while back I used graphical images to illustrate why you never, ever want to reuse the keystream of a stream cipher. Recently I've constructed similar examples to show the role of modes in using block ciphers. There's a nice set of block mode examples in Wikipedia, but I wanted to include the real result of applying the mode.

 

smileycolorsmileyecbsmileycbc

 

While cryptographic neophytes may want to know why the second encryption clearly failed (if you can read the message, the encryption failed), cryptographic experts may find it interesting to see other examples of cryptographic failures appearing graphically.

 

[There is a later post with more info on RC4 in Matlab

]

 

A while back I used graphical images to illustrate why you never, ever want to reuse the keystream of a stream cipher. Recently I've constructed similar examples to show the role of modes in using block ciphers. There's a nice set of block mode examples in Wikipedia, but I wanted to include the real result of applying the mode.

 

smileycolorsmileyecbsmileycbc

 

While cryptographic neophytes may want to know why the second encryption clearly failed (if you can read the message, the encryption failed), cryptographic experts may find it interesting to see other examples of cryptographic failures appearing graphically.

 

[There is a later post with more info on RC4 in Matlab]

 

Post category: 

Sharing Files on a Desktop Computer

The easiest way to share files on a desktop computer is for everyone to use the same login, and leave all the files on the desktop or in the "Documents" folder.

On the other hand, a desktop can be a personal thing. If I put a file somewhere, I like to know it'll still be in that spot when I get back. Computers are tricky enough. We don't have to add the work of other unpredictable humans to make them hard to use.

Once a household starts using multiple logins, you run into a completely different problem: how do you share things? I took all those pictures and my daughter wants to see them. We took turns typing in Xmas presents as we opened them, now where do we put the list so everyone knows what Thank You notes to write?

Post category: 

Dell Laptop

I just bought a Dell laptop. I generally buy from vendors I know, and St. Thomas has been buying Dell systems for the past several years. I might have bought an Apple, but their lowest base price was $1,000. I knew I could do a little better. In any case, I wanted to run both Windows and Linux. Running OS-X would have been a plus (I'm addicted to Aperture) but not worth the extra dollars.

The hardware seems solid - an XPS 1330 - and it's comfortably compact. It has thumbprint authentication that seems tolerably robust. The major size limiters, the RAM and hard drive, are easy to replace. So is the 802.11g network card. It came with "Windows Home Premium." I'm astonished at the amount of Dell-branded software you have to trim back. And I'm appalled that the default search engine, "Live.com," directs you away from OpenOffice.org when you go looking for it.

Post category: 

Boak's Puzzle: Disposing of Classified Trash

Recently I was skimming through the NSA's "classified history of COMSEC" (posted at governmentattic.com).  This "history" is a transcription of lectures by David G. Boak, who liked to explain NSA-related topics from a historical perspective. He clearly inspired a generation of NSA's employees. The last "real" page of the document contains a humorous story and a crypto puzzle (link to pdf).

The NSA had an incinerator in their old Arlington Hall facility that was designed to reduce top secret crypto materials and such to ash. Someone discovered that it wasn't in fact working. Contract disposal trucks had been disposing of this not-quite-sanitized rubish, and officers tracked down a huge pile in a field in Ft. Meyer.

How did they dispose of it? The answer is encrypted in the story's text!

Wordpress tag: 

Techno-zombies and Pluribus

I'm always amazed at how long a piece of apparently obsolete equipment can remain in service, especially in government service. Bruce Schneier's blog listed a link to NSA's 1991 video catalog at governmentattic.org. The catalog grants us an interesting if spotty view into the world of crypto gear and classified data collection systems.

I was particularly astonished to see inclusion of a video about the Pluribus - a long-obsolete Arpanet-era packet switch. I worked on the beast: it was overbuilt and underpowered. And unreliable (more on that another time). In the ideal world of tech, such obsolete junk should have been recycled by 1991. I was optimistic.

Password Recovery Speeds

Ivan Lucas of "Lockdown.co.uk" has posted an interesting summary of Password Recovery Speeds. These are scaled on the assumption that the attacker will do trial-and-error attempts of all possible permutations.
Wordpress tag: 
Post category: 

Donor Data Exposed from MN Senate Race

The election may have been last year, but the race for Minnesota's US Senate seat drags on. Back in January, Minneapolis techie and consultant Adria Richards went to visit the web site belonging to former Sen. Norm Coleman's campaign - he's shy about 200 votes and hanging on through court challenges.

What Richards found was a mess. Especially bad: the site did not prevent browsers from listing site directories - a huge security snafu. Richards navigated through the directories and found one with the intriguing title "db" - suggesting database. Sure enough, the directory contained a database that apparently lists Coleman's political donors.

Richards documented her visit via photos and screen captures and has posted a tour of Coleman's web site on her blog.

Post category: 

xkcd and humor

Bruce Schneier recently linked to an xkcd comic on rubber hose cryptanalysis. But here's the the comic that really made me laugh.

Rubber hose cryptanalysis stopped being funny when the rumor emerged about the fingerprint-controlled BMW that was stoley by cutting off a finger. Ugh.

Wordpress tag: 
Post category: 

A Microsoft-Centric World

Back in the 1970s when many of us were struggling to free ourselves from mainframes, the mantra in the computing world was "Nobody ever got fired for choosing IBM." No doubt Bill Gates was inspired by this to build his own empire. Today, people unblushingly swap "IBM" for "Microsoft" in that mantra.

Since converting back to the Macintosh I've been learning a lot about Microsoft-centric software. Several programs that ran on both systems have essentially withered, especially since the conversion to OS X. I'm most directly affected by Microsoft-centric teams at Intuit and at Adobe.

Post category: 

Pages

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer