Re: Adobe PDF crypto

[Kinichi <kitano@example.com>]

> Plea for non-technical help this time.

I think it is very technical.

> I'm writing a short article for a Japanese law journal on encryption
> and its implications for the law.  I want to include a few words
> about encrypted PDF.  If anyone knows what encryption method is
> used in these files, I would be most grateful for the info.

According to xpdf old archive,
(http://www.google.com/search?q=cache:www.cs.ruu.nl/mirror/CTAN/support/xpdf/+xpdf+RC4+crypt&hl=ja)
PDF uses RC4.

Check xpdf source code.