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Re: One-line password generator



On 25/08/17 12:15, Thomas Schmitt wrote:
>> Also, the theoretical vulnerability described in that man page is far
>> fetched.
> It is a mathematical fact. If you take a few theoretically unpredictable
> bits and inflate them to 128 bits, then the added size is no entropy,
> although it might be hard to distinguish this redundancy from the initial
> information.

This saves me from having to write a whole reply, since I know your
incompetence in cryptography is such that you are incapable of realizing
how incompetent you are.

I will justify my claim of incompetence.

You say that pseudo-random number generators can not add entropy and
this is a mathematical fact. This is true, and irrelevant.

It is also a mathematical fact that cryptographic algorithms you use
daily like DSA and Diffie-Hellman work over a cyclic group, including
their elliptic curve variants.

In the case of conventionall (not elliptic curve), the group in question
is the group of integers modulo “n”, where the group operatin is
*multiplication*.

DSA and Diffie-Hellman are broken if one can compute “discrete
logarithms”, that is, if one can compute “x”, given “b” and “(b^x) mod “n”.

Any cyclic group of order “n” is mathematically equivalent (isomorph) to
the group of integeres modulo “n”, where the group operation is *addition*.

In this group, computing “x” (or proving that it does not exists) such
that “ax=c” for any given “a“ and “c” is trivial (using the extended
euclidean algorithm). And this is mathematically (but not
computationally) equivalent to solving the discrete logarithm.

Why aren't these algorithms broken? Because this is only a mathematical
result. The isomorphisms can not be computed efficiently in practice, so
they are irrelevant for cracking. The same is the case with your
“mathematical fact”.

-- 
Do not eat animals, respect them as you respect people.
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