TSF Aware : random

Crypto History

Eric Brown — Fri, 11 Jul 2008 20:01:02 GMT

David LeBlanc wrote an excellent overview of encrypted documents in Office. A long, long time ago, I worked on the Word conversions team (it wasn’t even called Office then). As part of my job, I wrote a document encryption filter.

More specifically, I wrote (around 1990 or so) a document obfuscation filter. I say ‘obfuscation’ because one of the requirements was that the password had to be stored with the (encrypted) document. Of course, that rendered any possible security null and void, but the customer needed to be able to recover documents with forgotten passwords.

When David talks about XOR obfuscation, I believe that the incredibly weak security was a ‘feature’, not a bug – quite a few companies wanted to be able to prevent casual snoopers from reading their documents, but also wanted to be able to recover from a forgotten password.

DES was a standard in 1990 (it didn’t really fall until 1998), and I know the Office devs had an implementation around to use, as my manager wrote a real encryption filter using DES a couple of months after I wrote my obfuscation filter.

What Isn’t TSF good for?

Eric Brown — Wed, 25 Jun 2008 21:03:00 GMT

Well, for one thing, it’s not that great for grabbing the current selection in the foreground application.

There are several problems here:

1) You have to get your text service loaded into the target application. This can be slow.

2) Once your text service is loaded, you can only really work with TSF-enabled applications, which, sadly, are few and far between.

What do I recommend? There aren’t any really good solutions. MSAA doesn’t have good text support. UI Automation doesn’t have good native support (although it works very nicely in managed applications, and has good text support). You can use the clipboard, but users tend to be somewhat attached to their clipboard contents. (Saving & restoring the clipboard is possible, but can be tricky – application vendors will often register private clipboard formats that contain pointers which get invalidated when the clipboard changes. When you put the clipboard back, you will crash the application. Most vendors don’t do that, but it’s something you should be aware of.)

If you do decide to use the clipboard, then this guy has implemented a pretty fancy clipboard manager, and has a good discussion of various traps & pitfalls with the clipboard.

Steam Trek: The Moving Picture

Eric Brown — Fri, 15 Jun 2007 20:02:46 GMT

I don't have anything better to blog about right now (I'm in the middle of reviews and designs), so I thought I would share a bit of whimsy - notably, this steampunk version of Star Trek. If you're familiar with A Trip to the Moon, you will find this deeply funny. Hat tip to BT.

(If you do have suggestions, please contact me.)

LOLCode

Eric Brown — Thu, 31 May 2007 22:37:56 GMT

I suppose while I'm sending out the random link propagation, I should also mention LOLCODE - the programming language for really leet coders. I think it's related to the (deservedly) esoteric language valgol, from the 80's.

Update: on second thought, some examples might be useful. :)

Hello World (in LOLCODE):

HAI WORLD:

HAI
CAN HAS STDIO?
VISIBLE "HAI WORLD!"
KTHXBYE

A small example of valgol:

LIKE, Y*KNOW (I MEAN) STARTIF PIZZA =LIKE BITCHEN AND
   GUY =LIKE TUBULAR AND 
   VALLEY GIRL =LIKE GRODY**MAX(FERSURE)**2 THEN
  FOR I =LIKE 1 TO OH*MAYBE 100
      DO*WAH - (DITTY**2);
      BARF(I)=TOTALLY GROSS(OUT)
  SURE
  LIKE, BAG THIS PROGRAM;
  REALLY;
  LIKE TOTALLY(Y*KNOW);
  IM*SURE 
GOTO THE MALL

Desktop Tower Defense

Eric Brown — Thu, 31 May 2007 17:00:00 GMT

Enough about TSF for a while. :)

I found this amazingly addictive game the other day called Desktop Tower Defense. It's sort of the reverse of Lemmings - instead of saving all the lemmings, you need to squash them all. There's an insane number of levels, and it gets really challenging really fast.

Highly recommended.

Trek can has Cheezburger, too

Eric Brown — Fri, 04 May 2007 23:50:00 GMT

And now for something completely unrelated to TSF, or dictation:

I'm going to pile onto the incredibly funny Star Trek/lolcat spoof at granades.com. If you haven't seen it yet, it's pretty darn funny.