On 1/22/22 15:52, Krishna Myneni wrote:
> While many of the Forth programs written for 32-bit Forths were easily
> ported to 64-bit kForth, in a way that the programs work on both 32-bit
> and 64-bit systems, one notable exception was Jabari Zakiya's program
> for computing the md5 sum of a buffer or a file, hmac-md5.4th. The
> program's arithmetic and logic depended on a 32-bit cell size.
>
....
> ... The revised program, which
> still needs a fix to run on big-endian systems, may be found in the most
> recent kForth-32 master and kForth-64 master repos on GitHub. Here is a
> link to the revised program:
>
> https://github.com/mynenik/kForth-64/blob/master/forth-src/hmac-md5.4th
>
> It will run the tests, executed by the word HMAC-TESTS properly under
> both 32-bit and 64-bit (little-endian) systems.
....
A subtle problem in the definition of the word STORELEN limited the
maximum file size for which an accurate MD5 hash could be generated on a
64-bit Forth system, to about 256 MB. The tests provided in the program
for small data buffers did not pick this up, but I recently performed
tests of the word MD5FILE on kforth64 and found that it gave the wrong
hash for files above this size. The problem does not occur on 32-bit
Forth systems, for which the hmac-md5.4th program was originally written
-- on 32-bit systems, the file size is limited anyway to about 2 GB.

The problem has been fixed, and the revised hmac-md5.4th now appears to
work properly for file sizes exceeding 256 MB. The revised file may be
found at

https://github.com/mynenik/kForth-64/blob/master/forth-src/hmac-md5.4th

The largest file I tested with the program under kforth64 was about 2.2 GB:

---
md5file StarTrails.mp4

Bytesize: 2245592130
MD5 Hash: 12f30e7bdf4c6a4f9974f1473e79ad56
---
$ md5sum StarTrails.mp4
12f30e7bdf4c6a4f9974f1473e79ad56 StarTrails.mp4
---

The hmac-md5.4th program, under kforth64, is really too slow to be
useful for such large files. Critical parts of the program need to be in
the form of CODE words.

--
Krishna