Cryptography-Digest Digest #808, Volume #13 Mon, 5 Mar 01 16:13:01 EST
Contents:
Re: super strong crypto, phase 3 (Mok-Kong Shen)
Re: passphrase question ("Simon Johnson")
Re: The Foolish Dozen or so in This News Group ("Doom the Mostly Harmless")
Re: A question to John Savard (John Savard)
Re: super strong crypto, phase 3 (John Savard)
Re: => FBI easily cracks encryption ...? (Paul Rubin)
Re: Crypto security of pseudo-random sequences ("Simon Johnson")
Re: => FBI easily cracks encryption ...? ("Mxsmanic")
Re: => FBI easily cracks encryption ...? ("Mxsmanic")
Re: Was there ever a CRM-114 Discriminator? (Jerry Coffin)
Re: => FBI easily cracks encryption ...? ("Mxsmanic")
Re: Monty Hall problem (was Re: philosophical question?) ("Mxsmanic")
Re: => FBI easily cracks encryption ...? (Fogbottom)
Re: Monty Hall problem (was Re: philosophical question?) ("Mxsmanic")
Re: passphrase question ("Mxsmanic")
Re: beyond "group signatures": how to prove sibling relationships? ("Simon Johnson")
Re: => FBI easily cracks encryption ...? (Free-man)
Re: passphrase question (Tom McCune)
Re: Completly wiping HD: forget it, it can't be done. ("Simon Johnson")
Test vectors for 3DES with OFB or CFB ("Morten Vested Olesen")
----------------------------------------------------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: super strong crypto, phase 3
Date: Mon, 05 Mar 2001 20:14:58 +0100
John Savard wrote:
>
[snip]
> Instead of 448 + 64, then, we have to go to 384 + 128 to send a whole
> key each time. Or maybe 896 + 128. But I think that it is necessary to
> elaborate this kind of concept still further - and even then, there is
> no 'provable security' here, just an extra layer that will make things
> more difficult for the cryptanalyst.
>
> Initial keys:
>
> KA1 : initial block encrypting key
> Ka : new key to block encryption key transformation key
> KB1 : initial key encrypting key
> Kb : new key to key encryption key transformation key
> Kc : new key to mask encryption key transformation key
>
> First block:
>
> E(P1, KA1), where the first plaintext message P1 is composed of R,
> random data 896 bits long, and K2, a 128-bit random vector.
>
> Set:
> M1 = R
> KA2 = D( D( K2, KB1), Ka )
> KB2 = D( K2, Kb )
>
> Second block - and subsequent blocks follow the same pattern:
>
> E(P2, KA2), where P2 is composed of 896 bits of plaintext sent in this
> block, XOR M1, and K3, a 128-bit random vector.
>
> Set:
> KC2 = E(K3, Kc)
> M2 = E(M1, KC2)
> KA3 = D( D( K3, KB2), Ka )
> KB3 = D( K3, Kb )
>
> Thus: each block consists of 896 bits of plaintext and a 128-bit
> random vector which is used as a source of keys.
It seems that you use a block cipher of size 1024 bits and
a key of 1024 bits. Do I get that right?
There are many encryption and decryption operations for
sending 7/8 block of plaintext in your scheme. Would that
be much better than double or triple encryption (of whole
blocks of plaintext) with two or three keys and with the
following alternatives: (1) the keys are kept constant,
(2) the keys get incremented by some constant amounts after
processing a block, (3) the keys get incremented by amounts
governed by a PRNG after processing a block, (4) as (3) but
the incremented values are again processed by the encryption
algorithm, i.e. encrypted, to get the keys for use? Why?
(Note that here key informations are never contained in the
blocks transmitted.) Thanks in advance.
M. K. Shen
======================
http://home.t-online.de/home/mok-kong.shen
------------------------------
From: "Simon Johnson" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp
Subject: Re: passphrase question
Date: Mon, 5 Mar 2001 19:38:09 -0800
Anonymous <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> I was thinking about using a decryption passphrase for software like PGP
> and the like that would consist of a very long string of characters like:
>
> ......aaaaaaaaaa$$$$$$$$$$$fffffffffffDDDDDDD5555
>
>
> I would remember the passphrase by just remembering there are 7 periods,
10
> a's, 11 $'s, 11f's, and 7 D's, and 4 5's.
> So, the only thing in my mind would be 7 10 11 7 4 and the
> characters/numbers used. I know the security in public key encryption
lies
> in the protection of the private key, and that long private key
passphrases
> would make for a more secure system. Not taking into account things like
> keyloggers, remote electronic monitoring i.e TEMPEST, etc, just how secure
> is this method choosing a long passphrase?
>
> Just using the above letters once, the pass would be:
> .a$fD5 which is 6 characters in length.
>
> But I'm multiplying each character a number of times to get the pass.
> 7(.)11($)11(f)7(D)4(5)
>
> My final passphrase length is 7 + 11 + 11 + 7 + 4 + 5 = 45, which
satisfies
> the long passphrase requirement, and brute forcing something of that
length
> would be difficult from what I've read on the subject. But is the way I'm
> choosing that long passphrase weak? Is it any different that the original
> 7 character .a$fD5 passphrase when put up to a brute force?
> Comments/answers much appreciated, and please reply to the newsgroup only.
>
> Thanks,
> gerry
It does reduce the key-space, clearly 20 random characters contains far more
entropy than aabbccddeeffgghh... remember that's we are battling for here.
The more entropy we can get into our passphrase the better. Your scheme
prevents a straight brute-force attempt, but one could optimise their search
to your particular method and break it alot faster.
In my opinion, i wouldn't use this scheme. I'd just pick random words from
the dictonary. Something like "Cat Bomb Frog Hoorah" is easy to remember and
has a reasonable entropy content (exactly how much is hard to determine),
www.diceware.com is a site that demonstrates this approach.
Simon Johnson
------------------------------
From: "Doom the Mostly Harmless" <[EMAIL PROTECTED]>
Crossposted-To: alt.hacker
Subject: Re: The Foolish Dozen or so in This News Group
Date: Mon, 05 Mar 2001 19:37:23 GMT
It occurs to me that, however many foolish people there are in this news
group, you are certainly one of them.
After a certain point, it doesn't really matter whether your software does
as you claim or not. By now, you've convinced those who will ever believe
you, and will never convince those who openly criticize your posts.
Your personal attacks on those who do criticize you, while often amusing,
aren't really doing much besides pissing people off and hurting your
reputation. Personally, I'm far less inclined to believe you because of
these attacks than because of any technical arguments by those you seem to
have designated opponents.
Why? Because, imho, the point of this newsgroup is not to create enmity or
take sides so much as share information and point out flaws in others' work
in an open forum. If you don't want your software criticized, don't post
news about it in a newsgroup designed to improve software, theory, etc.
through constructive criticism. Most of the posts I've seen aren't of the
nature "You're stuff is shit, shut the hell up!" so much as "It seems to me
that you will encounter problems x,y,and z. How do you deal with them?"
which is exactly what this newsgroup is about.
I recognize that I'm not an expert on cryptography or cryptology, and am not
a regular poster. I'm not well known here, but I have been lurking on and
off for over a year and a half, and have come to believe that, while there
are occasional bouts of spurious rudeness, most of the wars are started by
people who come expecting god-like status because they've done something
they think is cool, or wizardry, or unique. People like you.
Perhaps I'm wrong about some or all of this. For all I know, this
dissention has boosted sales by 150%. Or perhaps you just enjoy shooting it
out in the trenches. Maybe I'm the only one who thinks this newsgroup is
all about constructive criticism.
--
To air is human....
--Doom.
------------------------------
From: [EMAIL PROTECTED] (John Savard)
Subject: Re: A question to John Savard
Date: Mon, 05 Mar 2001 19:25:14 GMT
On Mon, 5 Mar 2001 21:38:54 +0300, "Roman E. Serov" <[EMAIL PROTECTED]>
wrote, in part:
>Can you post here the url of your home page?
I do that whenever I post anything! It's in my .sig!
But in case that isn't working, my home page is at:
http://home.ecn.ab.ca/~jsavard/index.html
John Savard
http://home.ecn.ab.ca/~jsavard/crypto.htm
------------------------------
From: [EMAIL PROTECTED] (John Savard)
Subject: Re: super strong crypto, phase 3
Date: Mon, 05 Mar 2001 19:27:00 GMT
On Mon, 05 Mar 2001 20:14:58 +0100, Mok-Kong Shen
<[EMAIL PROTECTED]> wrote, in part:
>It seems that you use a block cipher of size 1024 bits and
>a key of 1024 bits. Do I get that right?
No. Although the message is divided into blocks of 1024 bits, my
example is built around a block cipher with a 128 bit block and a 128
bit key. The same key is used to encipher eight blocks of the message,
one of which is a new key, before switching. So it is closely based on
Douglas Gwyn's proposal.
John Savard
http://home.ecn.ab.ca/~jsavard/crypto.htm
------------------------------
From: Paul Rubin <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: 05 Mar 2001 11:45:13 -0800
[EMAIL PROTECTED] (Fogbottom) writes:
> Europeans have always tolerated police forces that demand that
> each and every citizen "register" his/her residence with the
> police. Americans never have. It's a fundamental difference
> between Americans and much of the rest of the world.
In practice I don't think that's much of a difference. In the US, you
might not have to register directly with the police, but unless you go
to fairly crazy lengths to conceal your residence, the police can
easily find you. For example if you have a telephone or electricity,
the phone or electric companies have to know your address and the
police can get the info from them. That's a standard method for bill
collectors to locate people. Also, if you rent an apartment, your
landlord has probably done a credit check on you, which means the
landlord's name is in your credit file. So someone running a credit
check can find out who your landlord is, and find out from your
landlord what apartment you rent, even if all your bills are sent to
some other address.
------------------------------
From: "Simon Johnson" <[EMAIL PROTECTED]>
Subject: Re: Crypto security of pseudo-random sequences
Date: Mon, 5 Mar 2001 19:58:11 -0800
Mok-Kong Shen <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
>
> If one has a statistically good pseudo-random sequence, e.g.
> one from the Mersenne Twister, and post-process it through
> the following methods:
>
> (1) Encryption with AES.
Yes, encryption takes predictable plain-text and transforms it
pseudo-randomly. The same would be true here but depends on the exact
configuration of the generator. e.g. how does it feedback?:
x(0) = key
x(i) = i'th random bit
AES(x,k) = AES block, x, with key, k.
x(i) = AES(x(i-1),x(0))
or:
x(0) = key.
x(i) = AES(x(i-1), x(i-2))
These are different systems, an idea of what you have in mind is needed,
really.
>
> (2) Hashing with SHA-1.
Same kind of idea as 1, except it would probably be vunerable to
linear-cryptanalysis (cause hashes don't need to be secure against it,
whereas stream generators do; the designers might not have bothered adding
resistance to this algorithm).
> (3) Using groups of n bits (e.g. n=24) to index the binary
> digits of Pi.
No, Pi is a well known determistic sequence and this would simply act as a
monoalphabetic substitution. The attack against the good prng would still
work with only minor change.
> (4) Further processing any of the above by taking the parity
> of groups of m bits.
Ack, unsure about this one, but i'd say No to be cautious. It probably
depends on the nature of the PRNG, doing this, with say, a straight LFSR
would probably yield a different security profile than that of an additive
generator, for example.
> which of these can qualify (or not qualify) as crypto-secure
> pseudo-random sequences? Why?
I doubt i've been much help, but the questions need proper cryptanalysis to
be answered in any kind of acceptable fashion.
Simon.
> Thanks in advance.
>
> M. K. Shen
> -------------------------
> http://home.t-online.de/home/mok-kong.shen
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Mon, 05 Mar 2001 20:06:21 GMT
"Joe H. Acker" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> Breaking strong crypto is the most expensive
> path of several dozens of paths that lead to
> your private information. Both government
> agencies and crooks are more likely to break
> into your appartment ...
An excellent point, often overlooked. Aside from breaking in in an
obvious way, experts could defeat even the fanciest lock and sneak in
undetected _far_ more easily than anyone could crack any decent
encryption scheme.
And even that isn't necessary. The spooks can just park a van across
the street from your house and watch what you type on your screen. That
would be a million times cheaper than trying to break your encryption
the hard way.
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Mon, 05 Mar 2001 20:06:27 GMT
"Fogbottom" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> You've been watching "The FBI Story" a bit too often.
I've never heard of that.
> But in general, local cops are just as well trained
> as FBI special agents and actually have far more
> street experience.
Why are local cops always getting into so much more trouble for
misdeeds, then?
------------------------------
From: Jerry Coffin <[EMAIL PROTECTED]>
Subject: Re: Was there ever a CRM-114 Discriminator?
Date: Mon, 5 Mar 2001 13:09:17 -0700
In article <[EMAIL PROTECTED]>,
[EMAIL PROTECTED] says...
[ ... ]
> >According to the Federation of American Scientists page on the B-52, one of
> >its systems is a CRM-114 Discriminator. Here's the link:
> >http://www.fas.org/nuke/guide/usa/bomber/b-52.htm
>
> >This may be a joke by FAS, I can't tell.
>
> It may simply be an error. Since they look far and wide for sources of
> information, perhaps someone assumed the movie was correctly
> researched in this particular.
While this page has a lot of accurate information, it also contains
at least a few things I'd consider questionable. Just for an obvious
example, while they accurately note that the B-52 is often call the
"BUFF", they claim it stands for "big ugly fat fellow", while the
expansion in wide use is "big ugly flying F'er."
For another example, they mention a rear-facing seat behind the co-
pilot as being "spare (instructor seat)". At least when I worked in
B-52s, that's where the tail-gunner sat. I suppose the AF may have
decided the B-52's tail gun wasn't particularly effective and taken
them out though -- AFAIK, only one B-52 was ever credited with a kill
on an enemy fighter using its tail gun (sorry, I don't remember the
tail number, but it was a D-model that shot down a MiG over Southeast
Asia).
--
Later,
Jerry.
The Universe is a figment of its own imagination.
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Mon, 05 Mar 2001 20:09:59 GMT
"Fogbottom" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> But you *will* have to register your residence
> with the police. In America, only convicted
> criminals released on parole have to do that.
This is a bit disingenuous. The government in the U.S. knows perfectly
well where to find just about everyone, even though the average person
is not required to register with the police. You still have to provide
an address for driver's licenses (and any other licenses), state taxes,
local taxes, transaction permits, and all sorts of things.
> Again, that's a fundamental difference between
> Americans and most of the world.
I agree. Unfortunately, Americans are gradually beginning to welcome a
police state as well. Much of the blame for this lies with the news
media.
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: sci.crypt.random-numbers,de.sci.informatik.misc,sci.math
Subject: Re: Monty Hall problem (was Re: philosophical question?)
Date: Mon, 05 Mar 2001 20:14:30 GMT
"Joe H. Acker" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> However, I do not believe that the truth
> table is correct.
The table covers every possibility, and shows every outcome. Which
entry is in error?
> I do believe that the probability to win in
> this special case does *not* depend on my
> knowledge regarding Monty's choice---wether
> or not I *know* which goat door Monty will open.
> The probability to win is determined by the
> fact that Monty will *always* open a door that
> does not contain the car.
Correct. That's why the truth table that I provided does not take
Monty's choice into account. The only thing that matters is that he
always eliminates a door that conceals a goat.
> I think that the truth-table may not contain
> the goat door Monty will always open.
I'm not sure what you mean. The truth table shows every possibility,
and every outcome. You can add up the results for yourself.
> But if I never have the choice to pick out the
> door Monty actually opens, the initial chances
> of winning are 50:50.
No. See the table.
> What do you think of that opinion?
I think you misunderstood the truth table. It's all there.
------------------------------
Date: 5 Mar 2001 20:13:54 -0000
From: [EMAIL PROTECTED] (Fogbottom)
Subject: Re: => FBI easily cracks encryption ...?
Crossposted-To: alt.security.pgp,talk.politics.crypto
In article <[EMAIL PROTECTED]>
[EMAIL PROTECTED] (Free-man) wrote:
> In my country (US), there are more government goons kicking
down doors
> and invading homes than there were in Nazi Germany.
You don't know much about history, do you?
Statements like that simply make most people laugh at you.
> In my country, it is not fashionable to persecute people for
the color
> of their skin. The current fashion is purge people with the
wrong
> color urine. In fact, the self-proclaimed, drug-free
supremists in my
> country have illegalized more humans than any other supremist
> group in history.
That may or may not be a good idea, but substance abuse is not
an inherited immutable characteristic - it's a conscious choice.
The majority of your fellow citizens have made a different
choice than you have.
> I say that you are a person who has not yet begun to question
> the bullshit that is taught at government indoctrination
centers
> (government schools) and government-controled media.
> Rich Eramian aka freeman at shore dot net
So buy a ranch in Montana and declare yourself an independent
country.
Or have you already tried that?
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: sci.crypt.random-numbers,de.sci.informatik.misc,sci.math
Subject: Re: Monty Hall problem (was Re: philosophical question?)
Date: Mon, 05 Mar 2001 20:18:34 GMT
"Darren New" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> Which is, incidentally, why this isn't the way
> the game worked. After Monty showed you the goat,
> you had your choice of sticking with your choice or
> taking $100. You never got the chance to switch
> doors after Monty opened one.
Really? Hmm. I don't actually remember much about the show. I'm sure
_some_ show allowed you to switch doors. Perhaps it was "The Price is
Right"?
------------------------------
From: "Mxsmanic" <[EMAIL PROTECTED]>
Crossposted-To: alt.security.pgp
Subject: Re: passphrase question
Date: Mon, 05 Mar 2001 20:18:41 GMT
The passphrase is no more secure than a six-character password, and is
thus vastly less secure than a well-chosen passphrase. The fact that
you repeat each of the characters has no effect, since your opponent
knows this.
"Anonymous" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> I was thinking about using a decryption passphrase for software like
PGP
> and the like that would consist of a very long string of characters
like:
>
> ......aaaaaaaaaa$$$$$$$$$$$fffffffffffDDDDDDD5555
>
>
> I would remember the passphrase by just remembering there are 7
periods, 10
> a's, 11 $'s, 11f's, and 7 D's, and 4 5's.
> So, the only thing in my mind would be 7 10 11 7 4 and the
> characters/numbers used. I know the security in public key encryption
lies
> in the protection of the private key, and that long private key
passphrases
> would make for a more secure system. Not taking into account things
like
> keyloggers, remote electronic monitoring i.e TEMPEST, etc, just how
secure
> is this method choosing a long passphrase?
>
> Just using the above letters once, the pass would be:
> .a$fD5 which is 6 characters in length.
>
> But I'm multiplying each character a number of times to get the pass.
> 7(.)11($)11(f)7(D)4(5)
>
> My final passphrase length is 7 + 11 + 11 + 7 + 4 + 5 = 45, which
satisfies
> the long passphrase requirement, and brute forcing something of that
length
> would be difficult from what I've read on the subject. But is the way
I'm
> choosing that long passphrase weak? Is it any different that the
original
> 7 character .a$fD5 passphrase when put up to a brute force?
> Comments/answers much appreciated, and please reply to the newsgroup
only.
>
> Thanks,
> gerry
>
>
>
>
>
>
>
> --Part_Boundary-26781F--
>
>
>
>
------------------------------
From: "Simon Johnson" <[EMAIL PROTECTED]>
Subject: Re: beyond "group signatures": how to prove sibling relationships?
Date: Mon, 5 Mar 2001 20:23:19 -0800
RSA can do this. We choose exponenets in two key RSA such that:
ed mod (p-1)(q-1)=1 were p and q are the factors of the modulo and e is the
public key and d is the private key.
Now in your system what we do is this....
we generate abcd mod (p-1)(q-1) = 1
a, b, c are the keys for your three 'siblings', d is the globaldecryption
key. P and Q are kept by the master.
Now for your aims:
> 1) Ci, Cj, Ck cannot prove who its parent (T) is
They don't know who has P and Q, if a, b & c are transmitted from an unknown
origin.
> 2) Ci, Cj, Ck cannot prove they are siblings
without d or (p and q) they can't prove this.
> 3) T can prove parenthood of children (e.g. Ci, Cj, and/or Ck)
He proves, using a cut and choose protocol that he knows the factors of
there moduli.
> 4) T is able to prove Ci and Cj are siblings
> 4a) (4), but T can do so anonymously
>
> 4b) (4) or (4a) without leaking proof that Ck is also a sibling
He can do this by multiplying c & d and using this value, show that he can
decrypt any invert what they co-sign, with a cut and choose protocol. If d
is selected at random, then Ci and Cj cannot prove Ck is a sibling without
breaking RSA.
Hope this helps,
Simon.
------------------------------
From: [EMAIL PROTECTED] (Free-man)
Crossposted-To: alt.security.pgp,talk.politics.crypto
Subject: Re: => FBI easily cracks encryption ...?
Date: Mon, 05 Mar 2001 20:25:19 GMT
On 5 Mar 2001 06:39:33 -0000, [EMAIL PROTECTED]
(Fogbottom) wrote:
>In article <[EMAIL PROTECTED]>
>[EMAIL PROTECTED] (Free-man) wrote:
>
>> >I don't want police & intelligence services reading my email
>or files. But
>> >I do want them to read the communications of people who might
>plant a bomb
>> >on the next plane I take.
>>
>> There is a better way to prevent terrorism. There is an
>alternative
>> to the police-state.
>
>History indicates otherwise.
>
>> Governments such as the US, China, Russia, etc.
>> should stop dropping bombs. Stop stomping on people. Stop
>their
>> systematic violations of human rights and freedom.
>
>You'll have to wait for the "Second Coming" or whatever your
>particular creation myth promises.
I am saying that government violence produces more violence.
A few examples. The downing of the passanger jet over Lockerbie
was a direct retaliation for the downing of an Iranian passanger jet
killing 350 civilians. The bombing of embassies are directed at
countries who violent interfere in other countries. The attack on a
US warship was a protest against US meddling. The bombing of of a
federal building in Oklahoma was a retaliation for the murder of a
religeous sect in Waco. Teaxas. The list goes on and on.
Remember alcohol prohibition when the US government decided
to treat millions of honest, decent people as criminals in order to
"protect the children" What was the
result of all thatt government violence? That violent and criminal
intervention into the free market produced an equally violent black
market. Sending police goons to attack people produced more violence.
Look at drug prohibition today. Millions of good people have been
assaulted, robbed, and arrested. This state-sponsored terrorism has
produced armies of thugs, spies, and informers, a violent underground
market, many prisons, and the widespread abuse of humans.
All this violence is produced by governments with too much power. The
solution is not to give more power to government. The solution is
more freedom for individuals which means less power for government.
Rich Eramian aka freeman at shore dot net
------------------------------
Crossposted-To: alt.security.pgp
From: Tom McCune <[EMAIL PROTECTED]>
Subject: Re: passphrase question
Date: Mon, 05 Mar 2001 20:21:34 GMT
In article <BwSo6.1363$[EMAIL PROTECTED]>, "Mxsmanic"
<[EMAIL PROTECTED]> wrote:
>The passphrase is no more secure than a six-character password, and is
>thus vastly less secure than a well-chosen passphrase. The fact that
>you repeat each of the characters has no effect, since your opponent
>knows this.
How would a potential opponent of any individual user know this?
Tom McCune
My PGP Page & FAQ: http://www.McCune.cc
------------------------------
From: "Simon Johnson" <[EMAIL PROTECTED]>
Subject: Re: Completly wiping HD: forget it, it can't be done.
Date: Mon, 5 Mar 2001 20:29:19 -0800
Paul Rubin <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> David Griffith <[EMAIL PROTECTED]> writes:
> > I wish to completly wipe a 2gig harddisk. There is now no data i want to
> > keep, however neither do i want anything to be recoverable.
>
> If you really want to totally trash the data on your disk, you must
> forget all those software things you were asking about. The only
> thing you can really do is take the drive apart, and sand the oxide
> off the platters with a grinding wheel. Then heat the metal discs to
> above the curie point for several minutes, to get rid of any remaining
> magnetization. Or better yet, melt them. Or slag the whole drive in
> a blast furnace.
>
> There is absolutely no way that software can 100% reliably totally
> erase a disk. You have no idea what the capacity of the disk really
> is. When you say 2 gig, it means 2 gig are available for your files.
> But the real capacity might be, say 2.1 gig, because there are
> reserved areas for flushing the internal drive cache on powerdown, for
> forwarding bad sectors to as the firmware detects them, and whatever
> else. All this happens completely behind the scenes and you have no
> way to know whether any of your data has ever been written to those
> areas. The areas are simply not externally visible.
>
> You simply cannot be sure you have totally destroyed the data, except
> by physically destroying the drive.
Yup, logic provails. Store, all your secure data on CD or a floppy, that way
its easier to destroy. CD's are better, because there's no magnetism to deal
with. Just blend, burn and forget! :)
Simon.
------------------------------
From: "Morten Vested Olesen" <[EMAIL PROTECTED]>
Subject: Test vectors for 3DES with OFB or CFB
Date: Mon, 5 Mar 2001 21:31:15 +0100
I am looking for testvectors for 3DES with CFB (8-bit) and 3DES with OFB
(8-bit). Do you know where I can find them or do you have such vectors
yourself, please let me know.
Thanks in advance,
Morten
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