PGP_060patch 1.0

Short:        _FAST_ 68060 patcher for PGP2.6.3i
Author:       roragusa@freenet.hut.fi (Roberto Ragusa)
Uploader:     roragusa freenet hut fi (Roberto Ragusa)
Type:         util/crypt
Version:      1.0
Requires:     PGP 2.6.3is
Architecture: m68k-amigaos

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THIS PROGRAM IS ONLY A PATCHER. IT DOESN'T CONTAIN ANY CRYPTO CODE.
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This is a small patcher that makes PGP a lot faster, and is only useful on
68060 processor.

The patch will make PGP executable (68020 version) 100 bytes bigger (but
more than 2 times faster!). If used on 020/030/040 CPUs the patched version
is probably a little slower (I didn't test that...), but it should work
without problems.

Technically: the critical loop of the calculations has been rewritten
without 32x32->64 mulu.l, thus avoiding missing instruction emulation
and multitasking suspension (jumping mouse).

A little test (encrypt/sign and decrypt of the PGP executable itself):
unpatched 8.64s and 8.00s, patched 4.32s and 3.77s (!!!).

I extensively tested the perfect working of the 060 PGP, so I'm pretty sure
it hasn't got any bug.

WARNING: if you are using the original PGP executable with CyberPatcher
and/or OxyPatcher, you could have some speed increase, but also spurious
errors due to inaccurate emulation of the mulu.l instruction. Technically:
the emulation routine does not preserve the X flag, but PGP does need that
the X flag isn't changed. No problems with the patched version (because no
mulu.l are emulated anymore and the rewritten loop takes care of X flag!).

If you don't trust this patch (you think it's a virus/backdoor...), just
either don't use it and continue to have that "jumping mouse", or
disassemble the changed code and check it on your own.

If you want to try it, use a command like this:
  PatchPGPfor060 c:PGP ram:PGP060
Then rename c:PGP to c:PGP.slow and copy ram:PGP060 to c:PGP.

Enjoy the speed!
Send me an Email, if you think this patcher is useful :-) .