Cryptography-Digest Digest #799, Volume #13 Sun, 4 Mar 01 20:13:01 EST
Contents:
Re: The Foolish Dozen or so in This News Group (Anthony Stephen Szopa)
Re: => FBI easily cracks encryption ...? ("Mark Livingstone")
Re: => FBI easily cracks encryption ...? ("Mark Livingstone")
Re: => FBI easily cracks encryption ...? ("Mark Livingstone")
Re: => FBI easily cracks encryption ...? ("Mark Livingstone")
Monty Hall problem (was Re: philosophical question?) (Benjamin Goldberg)
Re: Is BORG mental patient Linda Gore SSRIHater?? Re: Fake SSRIHATER ("c_h_r.i.s")
Re: The Foolish Dozen or so in This News Group (Anthony Stephen Szopa)
Re: Text of Applied Cryptography (Benjamin Goldberg)
Re: Monty Hall problem (was Re: philosophical question?) (Fred Galvin)
Re: The Foolish Dozen or so in This News Group ("Scott Fluhrer")
----------------------------------------------------------------------------
From: Anthony Stephen Szopa <[EMAIL PROTECTED]>
Subject: Re: The Foolish Dozen or so in This News Group
Date: Sun, 04 Mar 2001 15:49:47 -0800
Bob Harris wrote:
>
> Anthony Stephen Szopa recently wrote:
> > ...
> > As I have clearly stated above, the source code not only makes the
> > fclose() command but it checks for the return value from this
> ><major snip>
>
>
> include your software, the OS, the disk driver, the firmware in the disk
> controller, and perhaps other things), and what it does upon failure.
>
> Hope this helps.
> Bob
You haven't said much here except to point out that in my time
pressured response I made an understandable minor insignificant
error in reference which you have anxiously exploited. Leave the
innocence routine at home.
Insignificant especially in light of the fact that I posted the
very documentation of the fclose() function in the post cited below:
Subject: Re: OverWrite freeware completely removes unwanted files
from hard drive
Date: Fri, 02 Mar 2001 03:30:58 -0800
From: Anthony Stephen Szopa <[EMAIL PROTECTED]>
Newsgroups: alt.hacker
"...
Return Value
fclose returns 0 on success. It returns EOF if any errors were
detected."
BIG DEAL.
"But Anthony, you really should give consideration to the other
posts..."
If you read my posts including the thread cited above you would know
that I do and have. That's all I do.
What have I ignored? All the facts have been laid out.
And if you read the post I just made to Mr. Douglas A. Gwyn you will
see that he is agreeing with me.
But his mind is so twisted and he is so hell bent to disagree with me
and find fault with me that he doesn't even see it. Ergo his post.
"I haven't seen the whole dicussion..." WHOOPS!
It consists of this and the other thread cited above.
All these things are being considered in these threads.
Everyone has been saying "what about this and what about that." Half
are off topic or mere subterfuge and FUD.
Have you read my replies to them.
Don't just make generalities.
Be specific. What was the exact point raised and my reply to it that
you object to?
"I'm not going to get into the discussion of whether checking the
return value has relevance..."
Then why reply post at all? These are the matters that these
threads are addressing because they have direct bearing on whether
or not Ciphile Software's OverWrite Security program does in fact
overwrite the file 27 times as claimed.
You seem to think that we have to know exactly what is going on at
the machine level in order to feel confident that we understand what
is going on.
Well certainly this would be the ultimate test. But we can make
certain educated, well founded and logical determinations of what
is going on and why, as well.
Read some of my posts. Tell us exactly what your disagreement is
with something specific I said and why.
------------------------------
From: "Mark Livingstone" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Sun, 4 Mar 2001 11:58:00 +1000
=====BEGIN PGP SIGNED MESSAGE=====
Hash: SHA1
"Mxsmanic" <[EMAIL PROTECTED]> wrote in message
news:91Nn6.2622$[EMAIL PROTECTED]...
> "Sam Simpson" <[EMAIL PROTECTED]> wrote in message
> news:xtLn6.375$[EMAIL PROTECTED]...
>
> > Very true. BTW it's 'Galois'.
>
> Sorry. I knew it started with Ga-something, but I was too lazy to
> look it up.
Minor difference between cigarettes and math :-)
> > For machines storing classified information,
> > the NSA secure facility rules take over - this
> > hardware / software is likely to be quite
> > different from standard pc's.
>
> I question why the FBI has a need to handle information at these
> levels in the first place, at least on any regular basis. It
> sounds like there might be a lot of overclassification going on,
> which only weakens the security of classifications as a whole.
Now, as an Australian, I might not be in the country being discussed
but you do seem to be deprecating the FBI somewhat.
As I understand it, the FBI deals with:
* All your federal crimes
* All your interstate crimes
* Counter Espionage within the USA
* Counter Terrorism within the USA
* Internet crimes that they have 'recently' been assigned
* They often help other worldwide police forces with harder crimes
* Crimes against the USA committed internationally (eg those African
Embassy bombings)
* They helped with the Lockerbie bombing
* Security background checks
As such, why do you think they would NOT have data with as much
requirement for security as other three letter agencies?
=====BEGIN PGP SIGNATURE=====
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>
iQA/AwUBOqGhJOpKWuyElsBtEQK4lwCbBmqGujR8ZGpjruvrxYyp6ZyFIBwAoOHX
isdNnN39zsaPEK97WqGWGUHE
=ltZT
=====END PGP SIGNATURE=====
------------------------------
From: "Mark Livingstone" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Sun, 4 Mar 2001 12:38:21 +1000
=====BEGIN PGP SIGNED MESSAGE=====
Hash: SHA1
"Mxsmanic" <[EMAIL PROTECTED]> wrote in message
news:v_Wn6.7858$[EMAIL PROTECTED]...
> > ... so I think all your porno is safe.
>
> Why would anyone encrypt pornography with PGP?
>
> > Don't get me wrong, I use and like PGP, but it's
> > not the NSA and FBI that I worry about.
These days they hide their PGP encryptions within pornography :-)
Talk about a hot message.....!!!
=====BEGIN PGP SIGNATURE=====
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>
iQA/AwUBOqGqmepKWuyElsBtEQL8pACeN5rFtuxgy3he7OU01ImpPargfewAoN5r
p/FIVZyW9AoTYlVZD4GH90VW
=VMWz
=====END PGP SIGNATURE=====
------------------------------
From: "Mark Livingstone" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Sun, 4 Mar 2001 12:44:32 +1000
=====BEGIN PGP SIGNED MESSAGE=====
Hash: SHA1
"Free-man" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> No. Most of what law enforcement does is a violation of individual
> rights. Most of the laws that they enforce are unjust, bullshit
> laws that criminalize honest trade and peaceful behavior. Many
> cops are nothing but enforcement goons for the government mafias.
> They
> enforce monopolies on drugs, guns, gambling, etc. They commit
> more crimes than the bad guys.
True. I remember reading somewhere that on a number per hundred
thousand basis, more crimes are committed by cops than CCW holders.
I guess this must be true to some degree or Police Dept's would not
have to have Internal Affairs Dept's.
=====BEGIN PGP SIGNATURE=====
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>
iQA/AwUBOqGsDOpKWuyElsBtEQKZGgCg8Z0mxQxZL7uZIOfoYnLxPT8Cr10AoMXL
IQdaR4ri5IlDBU2HovM4txlN
=Rprz
=====END PGP SIGNATURE=====
------------------------------
From: "Mark Livingstone" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Sun, 4 Mar 2001 12:53:12 +1000
=====BEGIN PGP SIGNED MESSAGE=====
Hash: SHA1
"Mxsmanic" <[EMAIL PROTECTED]> wrote in message
news:qKKn6.2060$[EMAIL PROTECTED]...
> presume that for the FBI, which has traditionally been more
> concerned with things like guns than with Gaulois fields.
I suspect that the average news:rec.guns user or IPSC / IDPA
competitor has more training with their firearms than the average FBI
agent; certainly more than the average cop as media reports on
firefights continually prove.
> I suspect that FBI PCs are essentially identical to any other PCs.
Which hackers cracking their (and other govt / corporate) websites
continue to prove. The Human Factor reigns supreme :-(
=====BEGIN PGP SIGNATURE=====
Version: PGPfreeware 7.0.3 for non-commercial use <http://www.pgp.com>
iQA/AwUBOqGuFOpKWuyElsBtEQKn6wCffHsdOmWXFFGrYITNEWuwgnl5V/UAnjJH
ue8Hhet1WLMoEejQs39T1Qk5
=iX9S
=====END PGP SIGNATURE=====
------------------------------
From: Benjamin Goldberg <[EMAIL PROTECTED]>
Crossposted-To: sci.crypt.random-numbers,de.sci.informatik.misc,sci.math
Subject: Monty Hall problem (was Re: philosophical question?)
Date: Mon, 05 Mar 2001 00:05:35 GMT
Fred Galvin wrote:
>
> On Sun, 4 Mar 2001, Randy Poe wrote:
>
> > On Sun, 4 Mar 2001 17:46:31 +0100, [EMAIL PROTECTED] (Joe H. Acker)
> > wrote:
> >
> > >Here's my question to you, which is only interesting if you haven't
> > >yet heard about it:
> > >
> > >You participate in a TV-show and can win a car. The car is behind
> > >one of three doors, behind the two other doors are goats. You have
> > >to choose one door and choose door number 1. It is kept close. Now
> > >the moderator knows behind which door the car is, and says: "I'll
> > >show you something. "He opens door three and behind the door is a
> > >goat. Then he asks: "Would you like to stay with door number 1 or
> > >do you want to choose door number 2?"
> > >
> > >Are there better chances to win if you choose door number 2?
> >
> > It's called the "Monty Hall" problem after the host of the "Let's
> > Make a Deal" game show on which it's based. You can find it in the
> > sci.math FAQ.
> >
> > The answer depends on the rules the host is following. The
> > interesting result happens when the host knows which door contains
> > the car, and will always open a door with a goat after saying
> > "I'll show you something", whether or not you have already picked
> > the car.
> >
> > You should switch.
> >
> > If the host is malicious, only offering you another choice when he
> > knows you have the car, then it doesn't pay to switch (obviously,
> > since you're guaranteed to lose in that case).
>
> Good explanation. Now, what about this variant? Just leave out the
> part about Monty opening a door and showing you a goat. (We assume
> that Monty knows where the car is, and the car is more valuable than
> the goats.) After you pick door number 1, without opening any doors,
> Monty says, "Are you sure you wouldn't rather have door number 2?
> Here's the deal: you can keep door number 1, or you can trade it for
> door number 2." This is the *same* problem as the usual Monty Hall
> problem, right?
Nope, it's not.
The monty hall problem works like this:
33% of the time, we picked the right door the first time. When we
switch, we get a goat, 100% of the time.
66% of the time, we picked a the wrong door the first time. When we
switch, we get the car, 100% of the time.
If we always switch after seeing the goat, then we get a goat 33% of the
time, and a car 66% of the time.
In your version, there's no reason to prefer door #2. Switching and not
switching give equal benefit.
> Showing you the goat behind door number 3 is just for
> misdirection or dramatic effect; it shouldn't affect your decision.
Actually, it does.
Consider the three cases (we always pick door #1)
a) c g g
b) g c g
c) g g c
In case (a), we pick door #1, and he shows us one of the two goats.
Switching is a loss.
In case (b) or case (c), we pick door #1, and he shows us the goat
behind #2 or #3. Switching is a win.
Case (a) occurs 33% of the time, cases (b) and (c) occur 66% of the
time.
But if he doesn't show us the goat, we can't tell the difference between
(a), (b), and (c), so switching gives us 33% odds of a car, and not
switching gives us 33% odds of a car.
--
The difference between theory and practice is that in theory, theory and
practice are identical, but in practice, they are not.
------------------------------
From: "c_h_r.i.s" <[EMAIL PROTECTED]>
Crossposted-To:
alt.support.depression.medication,soc.culture.russian,soc.org.kkk,dk.snak.mudderkastning,rec.scouting.issues
Subject: Re: Is BORG mental patient Linda Gore SSRIHater?? Re: Fake SSRIHATER
Date: Sun, 04 Mar 2001 15:31:11 -0800
"Beeftain" <[EMAIL PROTECTED]> wrote:
>"Johan M. Olofsson" <[EMAIL PROTECTED]> wrote in message
>news:[EMAIL PROTECTED]...
>> Beeftain wrote:
>>
>> > "Johan M. Olofsson" <[EMAIL PROTECTED]> wrote in message
>news:[EMAIL PROTECTED]...
>> > > Beeftain wrote:
>> > >
>> > > > "alexplore" <alexplore@alexplore> wrote in message
>news:97jbuk$if6$[EMAIL PROTECTED]...
>> > > > >
>> > > > > Beeftain <[EMAIL PROTECTED]> wrote in message
>> > > > > news:97j635$1sli$[EMAIL PROTECTED]...
>> > > > > > "alexplore" <alexplore@alexplore> wrote in message
>> > > > > news:97j1m4$687$[EMAIL PROTECTED]...
>> > > > > > >
>> > > > > > > Beeftain <[EMAIL PROTECTED]> wrote in message
>> > > > > > > news:97j0ii$1jf5$[EMAIL PROTECTED]...
>> > > > > > > > Pippelip gokkelok!
>> > > > > > >
>> > > > > > > You must be mentally ill like Linda Gore!
>> > > > >
>> > > > > Linda Gore is a mental patient on the "crazies groups"...
>> > > > > Very mentally ill... married 4 times... does a lot of
>> > > > > "psychiatric medications"... for 23 years in fact...
>> > > > > that and fucking drunks and posting about how to stuff their
>> > > > > limp dicks up her cunt.
>> > > > >
>> > > > > "Diagnossing" her son.... sees that he needs a lot of psychiatric drugs
>> > > > > too...
>> > > > >
>> > > > > Disgusting piece of shit! Someone out there will be husband #
>> > > > > 5 sooner or later.... always a horny asshole that will fuck anything... Ask
>> > > > > Igor Chudov and Yelena Purdunkova about that :)
>> > > >
>> > > > Who are they?
>> > > >
>> > > > > > Well, Al Gore _is_ mentally ill...
>> > > > >
>> > > > > Not so much as his wife "Tipper" (hell kind of name is THAT!)
>> > > >
>> > > > She discovered these Parental Advisory-stickers. It's narrow-minded.
>> > > >
>> > > > > > not very less than George Bush.
>> > > > >
>> > > > > at least his wife ain't eating head-drug pills like "Tipper" :)
>> > > > > or Igor Chudov...
>> > > >
>> > > > No, but any wife of Bush must be brainwashed. Bush is a f...... maniac.
>> > > >
>> > > > Which group are you writing in?
>> > >
>> > > All of them, of course.
>> >
>> > The original, then.
>>
>> Beats me. I'm reading in soc.org.kkk like most good Democrats.
>
>Is this a place for fascists or anti-fascists? People against KKK?
NORMAL PEOPLE AGAINST HEADCASES AND PSYCHIATRIC MED JUNKIES
LIKE LIKDA GORE THE PROZAC WHORE. EXCEPT DESIPRAMINE OF COURSE
I TAKE 200MG/DAY. MY HARD-ONS LAST FOR DAYS
------------------------------
From: Anthony Stephen Szopa <[EMAIL PROTECTED]>
Crossposted-To: alt.hacker
Subject: Re: The Foolish Dozen or so in This News Group
Date: Sun, 04 Mar 2001 16:16:05 -0800
Bob Harris wrote:
>
> Anthony Stephen Szopa recently wrote:
> > ...
> > As I have clearly stated above, the source code not only makes the
> > fc<major snip>
>
>
> include your software, the OS, the disk driver, the firmware in the disk
> controller, and perhaps other things), and what it does upon failure.
>
> Hope this helps.
> Bob
P.S. EOF for error in fclose() and NULL for error in fopen()
(cringe) Can you ever forgive me for making reference otherwise?
Readers: if you are interested in this thread and the overwrite
thread all posts are not necessarily cross posted to both alt.hacker
and sci.crypt
You might want to check both news groups.
------------------------------
From: Benjamin Goldberg <[EMAIL PROTECTED]>
Subject: Re: Text of Applied Cryptography
Date: Mon, 05 Mar 2001 00:16:52 GMT
Henrick Hellstr�m wrote:
>
> "John Savard" <[EMAIL PROTECTED]> skrev i meddelandet
> news:[EMAIL PROTECTED]...
> > On Fri, 2 Mar 2001 18:43:52 -0500, "Ryan M. McConahy"
> > <[EMAIL PROTECTED]> wrote, in part:
> >
> > >http://www.cacr.math.uwaterloo.ca/hac/
> >
> > Wrong book....
>
> What's wrong about it? It is a book on applied cryptography, isn't it?
There's two books with similar titles, which occasionally people get
confused. There's "Applied Cryptography," and "Handbook of Applied
Cryptography." The URL above is for "Handbook of Applied Cryptography."
Ryan wants "Applied Cryptography." Unfortunatly for Ryan, only HAC is
available for free, and to get AC, you have to pay money. There is no
place to get AC, for free, on the net. Well, maybe it's available on
some warez site...
Maybe if you post a request on a warez newsgroup? It's not exactly hard
to buy a PDF and make it available for free. It's not getting caught
that's the problem :)
> > But you can buy a copy of the .PDF of Bruce Schneier's
> > book on the CD-ROM from Dr. Dobb's.
> >
> > John Savard
> > http://home.ecn.ab.ca/~jsavard/crypto.htm
>
> --
> Henrick Hellstr�m [EMAIL PROTECTED]
> StreamSec HB http://www.streamsec.com
--
The difference between theory and practice is that in theory, theory and
practice are identical, but in practice, they are not.
------------------------------
From: Fred Galvin <[EMAIL PROTECTED]>
Crossposted-To: sci.crypt.random-numbers,de.sci.informatik.misc,sci.math
Subject: Re: Monty Hall problem (was Re: philosophical question?)
Date: Sun, 4 Mar 2001 18:32:56 -0600
On Mon, 5 Mar 2001, Benjamin Goldberg wrote:
> Fred Galvin wrote:
> >
> > On Sun, 4 Mar 2001, Randy Poe wrote:
> >
> > > On Sun, 4 Mar 2001 17:46:31 +0100, [EMAIL PROTECTED] (Joe H. Acker)
> > > wrote:
> > >
> > > >Here's my question to you, which is only interesting if you haven't
> > > >yet heard about it:
> > > >
> > > >You participate in a TV-show and can win a car. The car is behind
> > > >one of three doors, behind the two other doors are goats. You have
> > > >to choose one door and choose door number 1. It is kept close. Now
> > > >the moderator knows behind which door the car is, and says: "I'll
> > > >show you something. "He opens door three and behind the door is a
> > > >goat. Then he asks: "Would you like to stay with door number 1 or
> > > >do you want to choose door number 2?"
> > > >
> > > >Are there better chances to win if you choose door number 2?
> > >
> > > It's called the "Monty Hall" problem after the host of the "Let's
> > > Make a Deal" game show on which it's based. You can find it in the
> > > sci.math FAQ.
> > >
> > > The answer depends on the rules the host is following. The
> > > interesting result happens when the host knows which door contains
> > > the car, and will always open a door with a goat after saying
> > > "I'll show you something", whether or not you have already picked
> > > the car.
> > >
> > > You should switch.
> > >
> > > If the host is malicious, only offering you another choice when he
> > > knows you have the car, then it doesn't pay to switch (obviously,
> > > since you're guaranteed to lose in that case).
> >
> > Good explanation. Now, what about this variant? Just leave out the
> > part about Monty opening a door and showing you a goat. (We assume
> > that Monty knows where the car is, and the car is more valuable than
> > the goats.) After you pick door number 1, without opening any doors,
> > Monty says, "Are you sure you wouldn't rather have door number 2?
> > Here's the deal: you can keep door number 1, or you can trade it for
> > door number 2." This is the *same* problem as the usual Monty Hall
> > problem, right?
>
> Nope, it's not.
>
> The monty hall problem works like this:
> 33% of the time, we picked the right door the first time. When we
> switch, we get a goat, 100% of the time.
> 66% of the time, we picked a the wrong door the first time. When we
> switch, we get the car, 100% of the time.
> If we always switch after seeing the goat, then we get a goat 33% of the
> time, and a car 66% of the time.
>
> In your version, there's no reason to prefer door #2. Switching and not
> switching give equal benefit.
>
> > Showing you the goat behind door number 3 is just for
> > misdirection or dramatic effect; it shouldn't affect your decision.
>
> Actually, it does.
> Consider the three cases (we always pick door #1)
> a) c g g
> b) g c g
> c) g g c
> In case (a), we pick door #1, and he shows us one of the two goats.
> Switching is a loss.
> In case (b) or case (c), we pick door #1, and he shows us the goat
> behind #2 or #3. Switching is a win.
> Case (a) occurs 33% of the time, cases (b) and (c) occur 66% of the
> time.
>
> But if he doesn't show us the goat, we can't tell the difference between
> (a), (b), and (c), so switching gives us 33% odds of a car, and not
> switching gives us 33% odds of a car.
All right. Can you explain the fallacy in my reasoning?
I pick door #1. Without opening any doors, Monty offers me the chance
to switch to door #2. I don't know what's behind door #3, could be the
car, could be a goat. However, if the car is behind door #3, then it
doesn't matter what I do, I'm choosing between two goats. Therefore,
in deciding what to do, I may as well assume that there's a goat
behind door #3. Now, how does the decision I make, on the assumption
that there's a goat behind door #3, differ from the decision I'd make
if Monty opened door #3 and showed me a goat?
--
People who don't have a sense of humor shouldn't try to be funny.
------------------------------
From: "Scott Fluhrer" <[EMAIL PROTECTED]>
Crossposted-To: alt.hacker
Subject: Re: The Foolish Dozen or so in This News Group
Date: Sun, 4 Mar 2001 16:06:15 -0800
It is written "Argue not with a fool, lest you be like him". Here I go
again ignoring that excellent advise...
Anthony Stephen Szopa <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> Scott Fluhrer wrote:
> >
> > Anthony Stephen Szopa <[EMAIL PROTECTED]> wrote in message
> > news:[EMAIL PROTECTED]...
> > > The Foolish Dozen or so in This News Group
> > >
> > > Read below. It'll be just like being forced to look into a mirror.
> > > You'll see who you all really are. Read it an weep.
> > >
> > > Here is why I think Ciphile Software's OverWrite program actually
> > > <majorsnip>
> >
> > careful with your fopen() and your fclose() functions won't help you
there
> > either.
> >
> > --
> > poncho
>
>
> "...After all, it's in control of the file system... See,
> logically..."
>
> What people fail to perceive quickly enough is that we are talking
> to several sick minds.
Of course, "sick minds" is being defined as "anyone with any technical
experience that indicates that the problem might be somewhat less trivial
than Anthony Szopa believes."
>
[Re: OS's buffering writes]
> I guess what you say is true even if I am writing to the file in
> append binary mode, I suppose? NOT!
I suspect you meant writing the file in update mode, but in any case, of
course the OS (and the disk driver, and the disk controller itself) can
buffer writes.
[Do any of you claim that any OS that you know of actually returns before
actually writing the data to the disk]
> "...known as Unix which as precisely this property..."
>
> You are slandering UNIX.
Hardly. You may not be aware of this, but several jobs ago, a large part of
my job was to maintain several versions of the Unix kernal. There was very
little that the Unix kernel did that I was unaware of (it helped somewhat
that, back in those days, the Unix kernel was considerably smaller). And, I
can swear unequivocally that those versions of the Unix kernel did have
precisely that property. If you disagree, may I ask after your
qualifications as a Unix kernel hacker?
In any case, I also mentioned (in a part you snipped) that I verified
expirementally that Linux (a Unix work-alike) did in fact have that property
(either that, or the disk on that computer spins at 384,000 RPM).
> So, what you are saying is that everything goes on in cache and that
> disk space is not under the operator's control. A file can be
> written to one place on a hard drive then read into cache.
> Processed then written to a completely different place on the hard
> drive. And this process can continue I suppose until the entire
> hard drive has been written over once and no bit locations have been
> overwritten.
Yes, at least in theory. And, according to Darren New, the Atari disk OS
has pretty much this behavior. I'm glad to see we agree.
>
> I would think this is not likely because of the optimization you
> claim to be expounding. The drive heads are already over these bit
> locations. To wander all over the hard drive writing to no
> predetermined fixed hard drive bit locations would be inefficient
> and un-optimizing.
For one, "unlikely" != "can't happen". The drive heads might not be "over
these bit locations", as some other program may have forced the drive heads
elsewhere. An OS might decide to write the sectors where the heads happen
to be. I have already mentioned one case (disk compression) where
relocating sectors is quite likely. Darren New mentioned another. An OS
attempting to do on-the-fly disk optimization is a fourth conceivable
example.
>
> With the reliability of computers these days most operations do take
> place successfully. There is no reason for the write locations to
> be moved around repeatedly. Give us a real world reason that happens
> regularly. You have only given us a once in a blue moon possibility
> that it might happen. What do you think, once in 100,000,000 writes?
Actually, in my previous posting, I gave one real world reason ("disk
compression"). Above, I gave three others.
And, in any case, the "mapping around write defects dynamically" algorithm
was not given as an example of relocating disks, it was a reason why write
buffering may be a valid optimization, even if you have an imperfect disk
(and, some systems have disks, such as SCSI, which claim to be perfect).
>
> Your hard drive was quiet because the heads did not move once they
> were in position. Is that about 1GB with no head movement in 156
> seconds? If you say so. This is not the point.
Are you claiming that my disk really spins at 384,000 RPM? If not, how
could it have possibly done one million writes to one sector in 156 seconds?
>
> The specific point is whether or not a write operation is actually
> taking place in Ciphile Software's OverWrite Security program. I am
> saying that it is by all my reasoning. The fclose() function with a
> conditional statement seems to force a write but you are saying that
> the head is wandering all over the hard drive and writing the
> resultant files repeatedly all over the hard drive in binary append
> mode.
>
> So what you are saying is that even if I just overwrite one character
> in a file this entire file will be loaded into cache if it will fit
> and this one character will be changed and then the entire file will
> be written to some other location on the hard drive so that there
> will be two files on the hard drive: the original file and this
> newly written file. And your position is that this is your view of
> optimization.
>
> Interesting.
Yes. Do you engage in strawman arguments often?
>
> "...These things typically have no knowledge of the file system..."
> You'll run to any length it is apparent to avoid the topic.
The fact that the disk caching routines may be be informed of fclose's is
irrelevant? I thought that fclose forcing writes was the basis of your
argument, and so a disk caching routine not being informed about it would
appear to be highly relevant. And, yes, some disk caches are ignorant of
fclose's -- I know, because I wrote some.
>
> "...Another nasty problem arises if disk compression is in use...."
> Run on. Run on.
Actually, if I were you, I'd look at disk compression real closely -- it's a
very sticky problem for file overwriters. For example, if a file originally
took up 2000 physical sectors, and you overwrote it with data that
compresses down to 500 sectors, why would you expect the OS to overwrite the
1500 remaining sectors?
>
> Has anyone seen the topic of this thread laying around here anywhere?
I thought the topic was "Is the algorithm that Anthony Szopa gave guaranteed
to properly overwite an arbitary file?". I claim that all the points I
brought up was relevent to that.
>
> "...disk drives often write bits to parts of the drive without you
> asking it to...."
>
> What does this mean: a bit here a bit there? Stopped running to
> other topics to run off about who knows what this means: "...disk
> drives often write bits to parts of the drive without you asking it
> to...."
Well, (at least, as reported earlier), disk drives often save data to hidden
parts of the disk for various reasons. This is perfectly valid, because as
long as the disk drive correctly performs the operations asked of it
("accept writes to sectors, and then give back that exact data when that
sector is later read"), it can do anything it finds expedient. This is
important to a disk overwriter, because writes may not overwrite this
redundant storage.
Other things that occur to me that a disk overwriter might need to worry
about:
- Disk optimizers -- run either at a user command, or as a background
process. These routines shuffle files around so they can be accessed
faster, usually by making them consecutive. I would claim that this is a
problem for a disk overwriter, because after the disk overwriter has
completed, there may still be copies of the file still remaining in the free
list, and this violates the security guarantee that the overwriter ought to
make.
- Versioning file systems. These are out-of-favor currently, but they do
exist.
- Transactioning file systems. I'm not sure how these works, but I wouldn't
be shocked to hear that they also move sectors around at times.
- RAID disks. Again, I'm not sure if this is really a problem, but have you
studied all the various RAID levels to verify that there isn't a problem
lurking there somewhere?
--
poncho
------------------------------
** FOR YOUR REFERENCE **
The service address, to which questions about the list itself and requests
to be added to or deleted from it should be directed, is:
Internet: [EMAIL PROTECTED]
You can send mail to the entire list by posting to sci.crypt.
End of Cryptography-Digest Digest
******************************
