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How do you predict the output of a pseudo random software number generator?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

Do you have the generator?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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Umm... yeah. But no hint what kind of a generator it is. I am certain that it does not take entropy from the operating system

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

I have seen contrived questions where from the data you can deduce what the generator looks like. But theoretically this is very, very difficult if not impossible. But in practice, poor implementation or bad seeds can make the job somewhat easier. It is known that both Windoze and Lunix have security flaws in their prngs.

Have you read Schneier's paper?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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No, what's that?

Okay, this is not a Windoze or Lunix prng. Besides I do not know how to execute the prng on Windoze.

As far as I know, the only flaw is that the OS can be flushed with a state of known entropy

*Last edited by Agnishom (2013-10-01 14:03:38)*

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

The papers probably describe how to. Why do you want to?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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Because its fun. Being able to predict things are fun.

However, I really do not want to crack the human PRNGs which determine their moods.

*Last edited by Agnishom (2013-10-02 02:02:24)*

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

Human prngs? What are those?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Brains. Which get entropy from

a) the level of fulfilment of the stomach

b) the amount of money one posseses

c) several stimulus

d) past memories

e) past entropies

f) entropies from others

.

.

xyz) and much more

and generate emotions about being happy or sad

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

Entropies? How do you define that?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Hmm

I do not know. I think I have been reading the wiki for too long

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

So what are you trying to do here?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Learn to crack PRNGs

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

And when you have done that?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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I've not done that. I am willing to do it.

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

There are two approaches both difficult. A math attack and a debugger.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Can you teach me those or any one of those?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

For the general problem you are asking I do not think so. I was still learning myself.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Ok, can you tell how you're learning?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

Know what a reverse engineer is?

Got to go offline, see you tomorrow.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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I've a little idea.

Tomorrow with respect to whom?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

To you I would say. By the time I am done you will be sleeping.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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What if we are not allowed to use a debugger?

What if we are cracking a PRNG on a remote computer?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 103,832

To access the prng of the operating system on a foreign machine you would need to cause a buffer overflow error. Of course such a result would qualify as a malicious act.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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What if it does not belong to the OS?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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