RE: [Algorithms] Message signature in token ring

[Brian H. <ho...@py...>]

>You're not qualified to verify, prove, proof, or otherwise=
 validate
>that it implements the algorithm correctly and *securely*=
 either.

Which is completely irrelevant.  The point is that SOMEONE is 
qualified, and if that code is not available for review, then NO=
 ONE 
except the people that wrote it in the first place are going to=
 even 
have that option.

With the sheer number of exploits found in Windows on a routine 
basis, I think the leeriness presented here is completely=
 rational.  

>There are other problems than the core algorithm. 

Of course there are.  But not having that or its implementation 
exposed IS a problem.

>It's true that platforms like PS2 present an issue, if Sony did=
 not
>think to provide standard libraries.

Which, of course, still doesn't solve an interoperability=
 problems.  

The best, non-crypto example of this is DirectPlay, which is=
 pretty 
much laughed at by most serious network game programmers I know,=
 is a 
complete nightmare when porting to non-Microsoft platforms, and=
 which 
is generally only defended by the people that worked on it, who=
 do a 
bunch of hand waving and make statements like "A lot of people=
 have 
spent a lot more time looking at this problem than you have, and=
 
there's no way you can do better".

Yet game programmers do.  Go figure.

>My major point was not to roll your own unless you absolutely=
 have
>to.

It's pretty clear you can go both ways on this issue.  I cannot 
recommend hardware mixing in DirectSound to anyone, yet it seems=
 that 
it is often suggested as the right thing to do because, hey,=
 "they" 
are going to get it right more often than the lowly game=
 programmer.

>I also pointed out that for many applications there is=
 perfectly
>good OS code available which will do the job. 

The problem, again, is who says it's "perfect good"?  Shall we do=
 a 
laundry list of Windows APIs that flat out have historically just=
 
sucked?  To be fair, we can also include the CRTL and Unix APIs=
 if 
you'd like, the point being that just because something is=
 "standard" 
or part of the operating system does not automatically make it=
 good 
or better than rolling your own solution.

>library deficient. That doesn't invalidate the sense of using=
 the
>provided libraries on Windows if you are not deploying on PS2.

IF there is a high likelihood that the Windows implementation is=
 
better than your own attempts and IF you don't care about=
 portability 
to other systems (Linux dedicated servers; Sun Ultra clusters;=
 etc.) 
then sure, it might make sense.

But not always.

-Hook