Dusty's EXEVALID utility fundemental flaw EXPOSED! *** WARNING: DO NOT USE THIS UTILITY! ***

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Subject: Dusty's EXEVALID utility fundemental flaw EXPOSED! *** WARNING: DO NOT USE THIS UTILITY! ***
Posted by:  p-0''0-h the cat (ES) (super.pooh@furryfreeware.invalid)
Date: Fri, 25 Apr 2014

Dusty's EXEVALID utility fundamental flaw EXPOSED!

*** WARNING: DO NOT USE THIS UTILITY! ***

When Dusty posted his EXEVALID utility in ACF on the 19/04 I was
immediately suspicious.

I quizzed him about the code and his strange use of ABS which he never
adequately explained preferring instead to go on a rampage to try and
discredit me despite the fact that I had never programmed in ASIC.

Dusty filled this and other groups with a flood of disinformation. What
was he trying to hide?

After extensive work at Pooh the cat and with the help of Dave@gchq
a.k.a Jax bear we can now conclusively prove that the use of ABS *DOES
NOT* solve the problem of integers above 7FFF resulting in an incorrect
negative file size.

See test program source at the end.

Using a hex editor I changed the first six bytes of an exe to

4D 5A 01 00 FF 7F

blocks = 7FFF last two bytes are stored low byte first

C:\ASIC>dusty.exe
Dusty buster. Version 1
Written by Pooh the cat April 25th, 2014

Enter filename: exe.exe
Totalsize    16776193 bytes

As we can see the file size returns positive

Using a hex editor I changed the first six bytes of an exe to

4D 5A 01 00 00 80

blocks = 8000 last two bytes are stored low byte first

C:\ASIC>dusty.exe
Dusty buster. Version 1
Written by Pooh the cat April 25th, 2014

Enter filename: exe.exe
Totalsize    -16777727 bytes

and contrary to what Dusty now says after FTR pointed out the purpose of
ABS you can see the file size returns a negative value and an incorrect
file size and therefore doesn't accurately return the file size as per
the MZ EXE header specification when the number of blocks > 7FFF.

Further tests in Pooh the cat labs is ongoing. Preliminary testing of
integer handling shows some very unusual results and therefore for the
time being I advise you NOT to use this utility.

This program obviously has a fundamental design flaw which Dusty has
tried to hide. His protestations that this is one of the limits of ASIC
are hard to believe. Pooh will now dedicate his Iams time to proving
Dusty wrong and programming reliably around this issue. If successful
one has to ask some serious questions about the release of this utility
in ACF.

Pooh the cat - making Usenet safe

Test source

print"Dusty buster. Version 2"
print"Written by Pooh the cat April 25th, 2014"
print""
print"Enter filename: ";
input filename$;
open"i",1,filename$
input #1,a$ BYTE
input #1,b$ BYTE
input #1,partialblock
input #1,blocks
close 1

blocks=abs(blocks)
totalsize&=blocks*512
partialblock=abs(partialblock)
partialblock=512-partialblock
if partialblock>0 then
totalsize&=totalsize&-partialblock
endif

print" "
print"Totalsize ";
print totalsize&;
print" bytes"

end

--
p-0.0-h the cat

Internet Terrorist, Mass sock puppeteer, Agent provocateur, Gutter rat,
Devil incarnate, Linux user#666, BaStarD hacker, Resident evil, Monkey Boy,
Certifiable criminal, Spineless cowardly scum, textbook Psychopath,
the SCOURGE, l33t p00h d3 tr0ll, p00h == lam3r, p00h == tr0ll, troll infâme,
the OVERCAT [The BEARPAIR are dead, and we are its murderers], lowlife troll,
shyster [pending approval by STATE_TERROR], cripple, sociopath, kook,
smug prick, smartarse, arsehole, moron, idiot, imbecile, snittish scumbag,
liar, total ******* retard, shill, and scouringerer.

Honorary SHYSTER and FRAUD awarded for services to Haberdashery.
By Appointment to God Frank-Lin.

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