Good Program That Creates OTPs?

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Michael Brown

Posted: Sat Dec 13, 2003 12:37 am

Guest

Jeremy Thorpe wrote:
[...]

Quote:

They will be destroyed forever after being used,

What about before they are used? Eg: your friend gets the CDs to the other
person's place, and he stores them ... where? Unless he keeps it strapped to
his body 24/7 this would be the obvious "attack" point. Given that they are
destroyed after they are being used, I'm guessing that you have 1 message
per CD (otherwise they could just break in and beat the CD out of him to get
the OTP used for previous messages, aka rubber hose cryptanalysis). So
having all those CDs on yourself 24/7 would be a little annoying.

And if you store them in a safe somewhere: TLA's agents break in to the
house (silently) and remove the safe at 1AM in the morning. They take it a
distance away so that they can use more noise-making attacks on it and get
the CDs. They copy them to a laptop, and by 4AM the safe is back at the
house and noone (except the TLA) is any the wiser. That's the biggest
problem with OTPs: key delivery and storage. With a normal cipher, the key
can just be remembered, and rubber hose cryptanalysis can get the contents
of previously sent messages. However, with an OTP, the keys must be stored
somewhere, which means an opponent, with sufficient resources (which would
be the only reason why OTP would be used), could get the "keys" for future
transmissions without the communicatees knowing.

[...]

--
Michael Brown
www.emboss.co.nz : OOS/RSI software and more Smile

Add michael@ to emboss.co.nz - My inbox is always open

Bas Ruiter

Posted: Sat Dec 13, 2003 12:42 am

Guest

Quote:

Be happy to post a message HERE, encrypted in a one-time-pad with my
credit card and pin number included.

What could be better than that?

I think you're missing the point.

--
Bas Ruiter

e-Mail: lordsnow@home.nl
www: http://members.home.nl/lordsnow

Tom St Denis

Posted: Sat Dec 13, 2003 6:43 am

Guest

"Jeremy Thorpe" <jeremythorpe@shore.net> wrote in message
news:70xCb.1297$0s2.528@newsread2.news.pas.earthlink.net...

Quote:

On Sat, 13 Dec 2003 02:57:29 GMT, Tim Smith
reply_in_group@mouse-potato.com> wrote:

In article <DnuCb.826$0s2.572@newsread2.news.pas.earthlink.net>, Jeremy
Thorpe wrote:
You apparently think that I am going to describe every detail of our
plans
on the Usenet. Which means that either you are a dumb motherfucker, or
that
you think that I am.

If your plan would be weakened by posting every detail to usenet, then
it is
a weak plan.

You are an idiot.

Wow, this conversation is highly purposeful already. We've got the "I know
you are but what am I?" defense....

Tom

Tom St Denis

Posted: Sat Dec 13, 2003 6:44 am

Guest

"Joe C" <jkc8289@bellsouth.net> wrote in message
news:f1xCb.9555$T14.204@bignews3.bellsouth.net...

Quote:

"Tom St Denis" <tomstdenis@iahu.ca> wrote in message news:hVuCb.4474
That's right cuz you're a fucking double-oh agent right? Grow up.

You're the asshat devising your own cryptosystem stating "I can only
trust
my security to an OTP...".

Tom
Hey Tom...did you forget??? You're in the sandbox.
http://home.bellsouth.net/p/PWP-brightwave

Gah? Um I didn't write either of those algorithms.

Tom

Tom St Denis

Posted: Sat Dec 13, 2003 6:45 am

Guest

"Tim Smith" <reply_in_group@mouse-potato.com> wrote in message
news:gSyCb.1612$Pg1.1346@newsread1.news.pas.earthlink.net...

Quote:

In article <70xCb.1297$0s2.528@newsread2.news.pas.earthlink.net>, Jeremy
Thorpe wrote:
If your plan would be weakened by posting every detail to usenet, then
it is
a weak plan.

You are an idiot.

That's nice. Look, if any aspect of your plan would be weakened by
posting
details, *why* are you keeping that in your plan?

Hint: J.T. is a troll. Just leave him alone. If he wants to walk around
ranting about this and that let him do that just don't respond!!!

Tom

Jan Panteltje

Posted: Sat Dec 13, 2003 8:45 am

Guest

On a sunny day (Fri, 12 Dec 2003 23:28:43 GMT) it happened Jeremy Thorpe
<jeremythorpe@shore.net> wrote in
<LasCb.681$0s2.495@newsread2.news.pas.earthlink.net>:

Quote:

On Fri, 12 Dec 2003 21:43:19 GMT, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Fri, 12 Dec 2003 17:28:42 GMT) it happened Jeremy Thorpe
jeremythorpe@shore.net> wrote in
eVmCb.323$0s2.198@newsread2.news.pas.earthlink.net>:

Does anyone here know of a program for Linux that creates OTPs and is
open source?

Thank you so much. I want to burn a bunch of them on a CD and send it to
a friend so that we can discuss a certain proprietary project in complete
secrecy, and this is the only encryption scheme I trust.

Jeremy

cat /dev/random > file
Type also:
apropos random
Then read all those manuals Smile

Jan

I can do that, Jan, and have /dev/random setup correctly, but what I need
to make my simplistic scheme work is the numbers 0000 to 9999 randomized.

When you trim the output of of /dev/random to 4 characters (by concatenating
several runs and then trimming it down) you get a lot of duplicates.

I wonder if there is some way I could just print out a list in order and
then use /dev/random to select a line at random and send it to the bottom
of another file?

Thank you much.

Jeremy

See my reply to Paul Rubin for some possibility.

/dev/urandom is not so secure as /dev/random,
but a lot faster.
Jan

Jan Panteltje

Posted: Sat Dec 13, 2003 8:45 am

Guest

On a sunny day (12 Dec 2003 15:48:52 -0800) it happened Paul Rubin
<http://phr.cx@NOSPAM.invalid> wrote in <7xk751wqaj.fsf@ruckus.brouhaha.com>:

Quote:

Jeremy Thorpe <jeremythorpe@shore.net> writes:
I can do that, Jan, and have /dev/random setup correctly, but what I need
to make my simplistic scheme work is the numbers 0000 to 9999 randomized.

That's elementary programming--there's nothing wrong with asking how
to do it, but it's just not really feasible for a newsgroup response
teach someone to be even a beginning programmer. You might try looking
at a programming book or website instead. "Learning Perl" might
be a reasonable choice.

Note also that you can only get a few dozen bytes (typically) of
random data from /dev/random before it freezes, because it won't give
you more data than it thinks it has gathered from physical randomness
in the computer.
Partly true, some dozen bytes at the time, but WAIT a second or 2.

As soon as enough randomness is 'detected' a next batch follows.
The file (in cat /dev/random > file) will keep growing.
You can do:
cat /dev/random
then while it waits between batches (about a second on my system),
hit a key, see what happens?
The keyboard interrupt causes randomness it seems, and the new batch now
immediately comes.
Now move the mouse hehe Smile

That will generate a LOT of interrupts, and the file grows fast.
Note all these block are different.
Jan
PS for Jeremy,
if you do this:
dd if=/dev/urandom bs=1000000 count=700 of=cdimage
It will take a few minutes...

Then burn the CD image like:
cdrecord -eject -v blank=fast dev=0,0,0 -data cdimage
then you have a random CD.

Give your friend 3 numbers (and the CD of cause) and use dd

dd if=/dev/cdrom bs=NUMBER1 skip=NUMBER2 count=NUMBER3 of=maskfile

You do this with your selected numbers, he does it too.
You XOR with 'maskfile', he does too.
Make sure you do not use the same mask area twice, should be no problem
with a 700MB CD and some text messages.
Of cause you can encrypt the message too, before the xor... or after it, with
a public key algo...
hehe

Here is a short C version of an xor program,
you can compile it with
gcc xor.c
that will generate the executable a.out.
Rename that to xor, then do in that directory:
../xor sourcefile maskfile outfile

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
int c,m;
FILE *fptri, *fptrx, *fptro;

if(argc != 4)
{
fprintf(stderr, "Usage: xor sourcefile maskfile outfile\n");
exit(1);
}

fptri = fopen(argv[1], "r");
if(! fptri)
{
fprintf(stderr, "could not open %s for read\n", argv[1]);
exit(1);
}

fptrx = fopen(argv[2], "r");
if(! fptrx)
{
fprintf(stderr, "could not open %s for read\n", argv[2]);
exit(1);
}

fptro = fopen(argv[3], "w");
if(! fptro)
{
fprintf(stderr, "could not open %s for write\n", argv[3]);
exit(1);
}

fprintf(stdout, "XORing file %s with %s to produce %s\n", argv[1], argv[2], argv[3]);

while(1)
{
c = fgetc(fptri);
if(c == EOF) break;

m = fgetc(fptrx);
if(m == EOF)
{
fprintf(stderr, "WARNING mask file too short! File not encrypted\n");
exit(1);
}
fputc(c ^ m, fptro);
}

fclose(fptri);
fclose(fptrx);
fclose(fptro);

fprintf(stdout, "Ready");

exit(0);
}

Hey, its Saturday and it rains...

Matthew Skala

Posted: Sun Dec 14, 2003 11:00 am

Guest

In article <Y3VydHdpbGw=.dccc7416dbfc8deac3b241d0df897ea9@1071334809.cotse.net>,
Hillary Clinton <no-one@nowhere.com> wrote:

Quote:

Janet managed to get her finger out of my twat long enough to tell me that
/dev/random is a PRNG- whatever that is. She said that's what Bill depended

/dev/random and /dev/urandom are the output ports of an entropy-pool true
random number generator similar in design to Counterpane's Yarrow.
/dev/random is the one that blocks in order to only output as much
randomness as is available; its output should be considered truly random.
/dev/urandom is more like a PRNG.

Quote:

Do a google seach and you'll find a mechanism to create your own random
stream using a simple Geiger counter and a luminous dial from a watch or

I'd trust /dev/random, which has been examined by a lot of people, in
preference to something homemade. One could combine the two,
though, by building the Geiger-counter device and feeding its output into
the /dev/random entropy pool. The resulting construction would be at
least as secure as secure as /dev/urandom (assuming the Geiger-counter
device's output is completely insecure) and also at least as secure as
the Geiger-counter device's output (assuming the other inputs to
/dev/random are insecure). That's almost certainly secure enough.

Quote:

I'm not certain why you only need to randomize the numbers between 0 and
9999, or whatever.

It was not me who wanted to do that.

Quote:

Here's another idea for you. Download both a 10 meg file and a one meg file.
Hash the 1 meg file after adding a large phrase as salt. Then use the output
from SHA-512 as the encryption key to crate the pad. You didn't start off
with a secret file, but I bet it's pretty random and secret by now.

A file downloaded from the Net is not secret. The hash of a such a
file is not secret. You can't take public numbers and turn them into
something "random and secret" by applying a public, deterministic
function. The procedure your describe is not secure, and you know
it. Plonk.
--
Matthew Skala
mskala@ansuz.sooke.bc.ca Embrace and defend.
http://ansuz.sooke.bc.ca/

Andrew Swallow

Posted: Sun Dec 14, 2003 3:34 pm

Guest

"Hillary Clinton" <hillary-no-spam@clinton.net> wrote in message
news:Y3VydHdpbGw=.705d451dda9ed8d0e430db5dc6f76d7e@1071447785.cotse.net...
[snip]

Quote:

What is "Plonk?"

Cheap whine. <g

Andrew Swallow

Richard Herring

Posted: Mon Dec 15, 2003 11:34 am

Guest

In message <7vtCb.1287$Pg1.19@newsread1.news.pas.earthlink.net>, Jeremy
Thorpe <jeremythorpe@shore.net> writes

Quote:

I would NOT stake my life on ANY computer-generated encryption scheme.

Sometimes the low-tech approach is superior. That's a fact that a lot
of Tekkies just won't ever accept.

The fact is that none of you know what the government and military and
corporations REALLY have.

That's trivially true. Like all conspiracy theories, it's also
unfalsifiable and therefore uninteresting.

Quote:

Who knew about the A-Bomb before Hiroshima? A lot of the leading experts
in the field were clueless until they read about it in the papers.

Nonsense. Most of them had been recruited to work on it.

Quote:

And computer projects are one heck of lot easier to hide than the Manhatten
Project.

Not if they need a brain (literally) the size of a planet Wink

Quote:

I have heard it said

by someone you trust?

Quote:

that the government, et al, is ALWAYS at least 20 years
ahead of whatever the public thinks is state of the art.

Could be. But pure mathematics, thermodynamics, the number of atoms in

the universe etc., do between them set some limits on what they can
achieve.
--
Richard Herring

Simon Johnson

Posted: Tue Dec 30, 2003 3:38 am

Guest

Quote:

I can do that, Jan, and have /dev/random setup correctly, but what I need
to make my simplistic scheme work is the numbers 0000 to 9999 randomized.

When you trim the output of of /dev/random to 4 characters (by concatenating
several runs and then trimming it down) you get a lot of duplicates.

I wonder if there is some way I could just print out a list in order and
then use /dev/random to select a line at random and send it to the bottom
of another file?

Thank you much.

Jeremy

Step 1. Take 2 bytes (16-bits) from /dev/random.
Step 2. Zero the higest two significant bits to give a 14-bit value.
Step 3. Take the value from Step 2 and if it's less than 10,000 you have
a single unbiased output between 0 and 9999. If it's over 10,000..
discard the value.

Repeat until you have enough values.

Simon.

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