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Re: ASCII versus binary

On Fri, 8 Aug 1997, William Allen Simpson wrote:

> Gentlefolk, I do not agree that we should use ASCII canonical forms.
> Indeed, after all the dust had settled, I had thought that we had agreed
> that all the escaping problems were not worth the effort.
> Folks went off and coded parsers for both ASCII and binary.  Binary was
> shown to be simpler and faster.

Parsing is fairly easy compared to the level of complexity that is
introduced by the 5-tuple reduction mechanism.

SPKI is a system that will be used in a hostile environment and in
high-risk applications (e.g. funds transfer and notary services). 
An implementor has to consider dozens of possible attacks, understand 
110% of the spec, and get his code bug free. That's asking a lot.

I wrote my s-expression parser in one night, but it took me half a week to
figure out pp 62-67 alone and after two weeks I'm still a bit uncertain
how to translate things like (* reorder-insert) into C -- and to convince
myself that it can't be misused. 

Honestly, I feel that something this big is bound to have bugs and some of
the bugs will be exploitable. 

- Markku-Juhani Saarinen <mjos@ssh.fi>