#42 RC4 decode plus others for 0.5

[Ross Johnson]

This is a reconstructed copy of David Mansfield's patch
to version 0.5 posted to the mdb-tools-dev list on
2004-06-13 and is intended to be applied directly to
the distro tar file after downloading. See:

http://sourceforge.net/mailarchive/message.php?msg_id=8705392

I have posted it here because the list archives have a
maximum message size limit, which truncates the patch.

It provides RC4 en/decryption of MDB files (works for
JET 3, don't know about JET 4). Parts of this patch
appear to have been incorporated into 0.6pre1, but the
essential RC4 en/decoding parts appear to have been
left out.

This patch has been reconstructed relative to the
current mdb-tools-0.5.tar.gz distribution with some
very minor header prototype additions to build it error
free on my Fedora Core 3 Linux system (these additions
aren't conditional but should not affect other systems).

The patch requires linking with libm for ceil and log10
functions (not related to RC4 I believe) and I'm not
sure where this should be specified (Makefile.am or
Makefile.in. David's original copy in the list archives
was truncated but appears to have added it to
Makefile.am (the correct place I think), but this
caused problems running the auto tools. I added it to
Makefile.in which works when applying the patch to the
distribution tar file.

[Ross Johnson]

RC4 en/decrypt patch plus others for 0.5