5 ms·

The Wrong Level of Abstraction

39 points by bdfh42 17y ago

Oompa 17y ago
I would've never guessed using a library would be easier than coding the functionality that the library provides.
- niyazpk 17y ago
  The article is not that bad, compared to the last 5 or so from Jeff. Atleast what he is saying is correct this time. And this time the article is HN worthy IMHO.
  - cracki 17y ago
    saying the right stuff isn't HN worthy, IMHO. saying the right stuff when nobody knows of believes in it, that's HN worthy.
- deleted 17y ago
  [deleted]
tptacek 17y ago
The comments, though. My god, the comments. "Yeah, but how can you trust a cryptography library? This one time, I used a library to parse email addresses, and I wound up having to do it myself. It's like with your car, do you really need the mag-alloy wheels, or shouldn't you just do things right yourself. Like this one time, I took AES and randomized the S-Boxes so even the NSA couldn't decrypt it and" --- sorry, I lapsed into comments from Colin Percival's blog.
- tdavis 17y ago
  Maybe it's just me, perhaps because I didn't understand a damn word in this article[1], but I've never attempted to implement any sort of cryptographic functionality myself. Occasionally I'll MD5 something for the sake of convenience, but it is never meant to secure anything. I don't know why so many programmers actually write their own code. It's silly. There are people way smarter than me in basically every programming domain that exists. I'd rather use their code. [1] http://www.daemonology.net/blog/2009-06-11-cryptographic-right-answers.html http://www.daemonology.net/blog/2009-06-11-cryptographic-rig...
johnm 17y ago
I love how Atwood's piece (let alone many of the comments) is directly an example of what he's talking about. I.e., while's many of his points are true they miss a much more critical point... When it comes to security all discussion must start with: "what are your threat & risk models?" Without that, all of the rest of the discussion are pointless, delusional, wastes of time.
- notaddicted 17y ago
  Here is the usual human algorithm for that sort of big question. a. What should I be worried about? b. What is everyone else worried about? c. I'm worried about $b.
sho 17y ago
"One of those alternatives would be a full-blown library, perhaps something like Bouncy Castle, or Keyczar, or cryptlib." .. none of which are (easily) usable from Ruby. Would anyone have any recommendations for the gem of programming languages?
- tptacek 17y ago
  If you can't write Keyczar bindings for Ruby, maybe cryptography is a little ambitious for you too. Note: Bouncy Castle is not a recommended high-level crypto library. More grevious errors are committed in the name of Bouncy Castle than almost anything but OpenSSL.
  - sho 17y ago
    Of course I have the technical ability to write C bindings (or whatever it is) for $arbitrary_library. Your whole thesis, however, is "crypto is hard, so don't try to do it yourself", so I asked for suggestions on how not to do it myself. And I only mentioned "Bouncy Castle" because it was suggested in the article.
geebee 17y ago
I agree with Jeff's general statement "don't reinvent the wheel, unless you plan on learning more about wheels" but I think it's important to keep in mind the costs of going to a higher level of abstraction as well. Every framework I've used claims to improve productivity, and they all ask why you'd want to reinvent the wheel rather than use iBatis or or Hibernate or JPA or EJB or Spring or Guice or GWT... Some of these frameworks actually deliver on the promise of increased productivity. Others don't at all. A few do help once I've learned them, but aren't worth the sunk cost (ie., they do improve my productivity once I've sunk 200+ hrs into reading and configuring, but not enough to offset the time invested). One reason I like "low level" coding is that I know I can get the job done in a straightforward manner. It'll take a lot of typing, and it may be tedious, but so is dumpster diving through log files to figure out why the "wheel configuration file" isn't finding the "lug nuts" tag, only to then discover that volvo v90 has only been compatible with the deprecated version of the hubcap plugin ever since Ford stopped contributing to the "tricked out rim" facade. "Trivial" doesn't mean quick and easy, it just means that conceptually, you can see a path from here to there that doesn't have any serious question marks. In this sense, reinventing the wheel is often "trivial". Let's not understate how much time a programmer can lose by trying to make sure he doesn't lose time by reinventing the wheel.

39 points by bdfh42 17y ago

Oompa 17y ago

I would've never guessed using a library would be easier than coding the functionality that the library provides.

niyazpk 17y ago
The article is not that bad, compared to the last 5 or so from Jeff. Atleast what he is saying is correct this time. And this time the article is HN worthy IMHO.
- cracki 17y ago
  saying the right stuff isn't HN worthy, IMHO. saying the right stuff when nobody knows of believes in it, that's HN worthy.
deleted 17y ago
[deleted]

tptacek 17y ago

The comments, though. My god, the comments. "Yeah, but how can you trust a cryptography library? This one time, I used a library to parse email addresses, and I wound up having to do it myself. It's like with your car, do you really need the mag-alloy wheels, or shouldn't you just do things right yourself. Like this one time, I took AES and randomized the S-Boxes so even the NSA couldn't decrypt it and" --- sorry, I lapsed into comments from Colin Percival's blog.

tdavis 17y ago
Maybe it's just me, perhaps because I didn't understand a damn word in this article[1], but I've never attempted to implement any sort of cryptographic functionality myself. Occasionally I'll MD5 something for the sake of convenience, but it is never meant to secure anything. I don't know why so many programmers actually write their own code. It's silly. There are people way smarter than me in basically every programming domain that exists. I'd rather use their code. [1] http://www.daemonology.net/blog/2009-06-11-cryptographic-right-answers.html http://www.daemonology.net/blog/2009-06-11-cryptographic-rig...

johnm 17y ago

I love how Atwood's piece (let alone many of the comments) is directly an example of what he's talking about. I.e., while's many of his points are true they miss a much more critical point... When it comes to security all discussion must start with: "what are your threat & risk models?" Without that, all of the rest of the discussion are pointless, delusional, wastes of time.

notaddicted 17y ago
Here is the usual human algorithm for that sort of big question. a. What should I be worried about? b. What is everyone else worried about? c. I'm worried about $b.

sho 17y ago

"One of those alternatives would be a full-blown library, perhaps something like Bouncy Castle, or Keyczar, or cryptlib." .. none of which are (easily) usable from Ruby. Would anyone have any recommendations for the gem of programming languages?

tptacek 17y ago
If you can't write Keyczar bindings for Ruby, maybe cryptography is a little ambitious for you too. Note: Bouncy Castle is not a recommended high-level crypto library. More grevious errors are committed in the name of Bouncy Castle than almost anything but OpenSSL.
- sho 17y ago
  Of course I have the technical ability to write C bindings (or whatever it is) for $arbitrary_library. Your whole thesis, however, is "crypto is hard, so don't try to do it yourself", so I asked for suggestions on how not to do it myself. And I only mentioned "Bouncy Castle" because it was suggested in the article.

geebee 17y ago

I agree with Jeff's general statement "don't reinvent the wheel, unless you plan on learning more about wheels" but I think it's important to keep in mind the costs of going to a higher level of abstraction as well. Every framework I've used claims to improve productivity, and they all ask why you'd want to reinvent the wheel rather than use iBatis or or Hibernate or JPA or EJB or Spring or Guice or GWT... Some of these frameworks actually deliver on the promise of increased productivity. Others don't at all. A few do help once I've learned them, but aren't worth the sunk cost (ie., they do improve my productivity once I've sunk 200+ hrs into reading and configuring, but not enough to offset the time invested). One reason I like "low level" coding is that I know I can get the job done in a straightforward manner. It'll take a lot of typing, and it may be tedious, but so is dumpster diving through log files to figure out why the "wheel configuration file" isn't finding the "lug nuts" tag, only to then discover that volvo v90 has only been compatible with the deprecated version of the hubcap plugin ever since Ford stopped contributing to the "tricked out rim" facade. "Trivial" doesn't mean quick and easy, it just means that conceptually, you can see a path from here to there that doesn't have any serious question marks. In this sense, reinventing the wheel is often "trivial". Let's not understate how much time a programmer can lose by trying to make sure he doesn't lose time by reinventing the wheel.