Questions tagged [random-number-generator]
A random number generator is a software or hardware solution which functions as a generator of (real or pseudo) random numbers (or bits).
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Conformance of Windows Random Number Generator (SP800-90A) with Key Lifecycle Security Requirements of the BSI
The BSI (Federal Office for Information Security in Germany) has published a paper detailing the requirements of cryptographic modules for certain applications in the energy sector: Key Lifecycle ...
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Is there a counterpart of /dev/random and /dev/urandom in Windows NT systems?
I am trying to implement a TRNG on Windows and among other entropy sources, I want to extract raw bytes from various kinds of CPU and process info.
As per my knowledge, BCryptGenRandom is a CRNG in ...
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Manual entropy collection from sources with an arbitrary base
I'm writing a tool for manually collecting entropy from sources like coins and dice, and I'm wondering how to best deal with the case where the desired number of bits of entropy is not representable ...
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symmetric key generation - random number vs pbkdf2
I am working on improving my grasp on applied cryptography. Following question is just for learning/understanding purposes..
Lets say I want to generate a 16 byte key that I want to use for some ...
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Can this algorithm be called a RNG?
So I developed this algorithm as RNG, although it looks random to me, I wanted to know the opinion of more experienced persons in the topic.
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Are TRNGs used in low power devices? Why?
I read somewhere that TRNGs are better than cryptographic algorithms that generate pseudo-random numbers (PRNGs) because these algorithms are more energy intensive than TRNGs.
By low power devices, I ...
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Can I predict CryptGenRandom on my own device?
I have a Windows 10 laptop with an algorithm that creates a random number using the PRNG CryptGenRandom. According to Wikipedia:
Because CryptGenRandom is the de facto standard CSPRNG in Win32 ...
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What are the state-of-the-art TRNGs today?
How fast are the fastest ones? Which ones have the most entropy? Which ones are the most practical ones?
I tried looking for answers on Wikipedia and also, I tried reading papers, but I am couldn’t ...
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Is it valid to transform the tested sample file and re-test, rather than invent additional randomness tests?
I'm enhancing the venerable ent randomness test suite. And I came across this idea in On Independence and Sensitivity of Statistical Randomness Tests.
"To ...
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Can someone give a comprehensive guide on how to run NIST SP 800 90B entropy assessment c code in windows? [closed]
I am trying to run the github code in windows 11. I don't know what all I need to install in my laptop to run the C++ code. It would be a great help if someone can point out the steps to run the code.
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Optimize the speed of a safe prime finder in C
I am trying to implement the Schnorr’s identification protocol in C. I need a safe prime in order to be able to find a generator of the cyclic group efficiently. The problem is that my program takes ...
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Is Python secrets module using a unsafe RNG on Windows?
The Python secrets module claims to produce cryptographically secure random numbers. I did some research on which random number generator is used when you call the secrets module on Windows. I found ...
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Generating X ids on Y offline machines in a short time period without collision
In theory this is what I have :
Around 10 000 offline machines
Each machine will generate around 10 000 ids
I can program the machine in any way I want, but I prefer a low memory and low cpu
They all ...
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A HRNG that is NIST 800-90 compliant is not suitable for use for OTP generation right?
A HRNG that is NIST 800-90 compliant must use a DRBG in some way regardless of whether it adheres to a RBG1, RBG2 RBG3(XOR), or RBG3(RS) construction. This violates the requirement that the OTP is ...
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Why does NIST SP 800-90C RBG3 construction require XOR or reseeding a DRBG with a physical entropy source to produce full entropy?
NIST 800-90C defines 3 classes of random bit generation (RBG) constructions: RBG1, RBG2 and RBG3. All constructions must include a DRBG from NIST SP 800-90A. The particular construction in question is ...
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Academic papers for the pros and cons of password based system and digital signature with challenge and response system
I don't really know what should be the correct title for this and the community can correct it after reading.
I was the author of PKDSA (Searchable on github).
I have the idea to do it because I feel ...
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How did the VB6 PRNG generate a byte output from a specific seed, and how to replicate in C? [closed]
I'm hoping to get some help regarding an old problem that has eluded me. I'm trying to figure out how the VB6 PRNG was used to generate a byte output from the two byte seed that the Randomize() ...
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Predicting compromised OpenSSL 3.0 DRBG
The OpenSSL 3.0 rand function's DRBG uses the getrandom() system call to get 48 bytes of secure entropy from the kernel. It also ...
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theoretical hash collisions vs random number collisions
I have a theoretical question about the probability of collisions of hashes versus random numbers. I'm not interested in the exact probabilities. The exact hash function is not relevant (we can assume ...
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Collision Resistance in Random Bit Generator
Consider following simple RBG where SHA-256 of random noise (more than 200Bytes of 4 bits entropy per byte) is computed to produce 256 output bits
$\text{output} = \operatorname{SHA-256}(\text{...
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What is the result of not connecting the 1st register to the xor gate in LFSR?
I designed 8 bit lfsr in vhdl. According to mathematical theory, I xor processed the outputs of registers 1, 4, 5, 6 and 8 and connected them to the input of register 1. theory says that if I give the ...
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Communication through shared seed in RNG
Given that there are two parties, and a process has been conducted by which both parties are knowledgeable of a shared value p, how could two parties communicate with each other over a public channel ...
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Is a pseudorandom function (PRF) also a one-way function (OWF)? If yes, how can we proof that a PRF $f_k$ is a OWF? If no, what is the closest work?
Let $f_k$ be a PRF. We claim that $f_k$ is a OWF. PROOF let $f_k$ is not a OWF, there exists a $PPT$ algorithm $A$ that can invert $f_k$ with non-negligible advantage. Even if we know the input $x$ ...
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Public seed expansion for uniform reference strings
Many cryptographic protocols are parameterized by a uniformly random reference string (e.g. the commitment key for Pedersen commitments).
Our goal is to publicly generate the random values of this ...
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How to generate random numbers within a range (0,n) from random bits?
What is a good method to generate random numbers between 0 and n from random bits?
For example, I have a one million random bits generated according to NIST SP 800 90 publications. Now I need to ...
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How can 4 users generate a provable fair random number?
The past few weeks I have been trying to solve a difficult problem.
I have asked some cryptography experts but unfortunately they had no clue on how to solve the problem.
The situation is as follows, ...
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Concatenating RNG with PRNG
Is it secure to concatenate numbers from an RNG with numbers from a PRNG? I was thinking to throw a dice and use four outcomes to use as real random numbers, one outcome to change to the next ...
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How bad are human-generated random numbers really (One Time Pad)?
This is a pretty open question, so I'm mostly looking for gut reactions from experts more educated than I.
Given these assumptions which are easy to verify with a quick Google search:
One Time Pads ...
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Any simple, cryptographically secure AES-based DRNG?
I am looking for a DRNG/DRBG (cryptographically secure) algorithm/function (which I can program into js). I am looking to use a DRNG as a seed generator for generating multiple, identical AES keys on ...
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Pseudo Random Number Generator test uniform distribution
If I test the Pseudo Random Number Generator(PRNG) and it satisfies the serial test, it is not sure that the resulting distribution is uniform. Is my observation correct? If it is correct, what test ...
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Drawbacks of multiple sources of entropy for AES
Since AES needs IV to be random (unless fed by a unit test), I was wondering how to properly handle it.
I know that Intel/AMD now supports the rdrand64 function but ...
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NodeJS : Generate unique 16-digit decimal values [closed]
Situation
I need to generate unique 16-digit decimal values in NodeJS API or C++ Addon.
It's used internally in my organization (gift card id). And performance doesn't matter as it's generated non-...
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ChaCha-based Sponge PRNG fails PractRand suite
TL;DR: My simple ChaCha-based sponge PRNG is getting "unusual" evaluation from PractRand test battery pretty reliably, sometimes even within the first GB; I'm trying understand why.
I was in ...
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Entropy of a counter
I wondered whether my understanding of entropy is correct, that a 256-bit counter that starts at 0 and counts to 2^256 - 1 by a <...
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Can I emit a block shorter than internal state of (any) Xorshift PRNG without having to compute the full block?
Xorshift family pseudo-random number generators have a variety of different internal state sizes.
Let's take one of this family called xorshift1024*.
My question is:
Having xorshift1024* a internal ...
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Examples of frauds discovered because someone tried to mimic a random sequence [closed]
[Moderator note: this question now lives there]
So, I'm preparing a talk about the well known fact that humans are bad at the task of generating uniformly random sequences of numbers when asked to do ...
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Proof-of-Randomness with an EC Public Key
I will be using a tRNG to generate EC keypairs on a Secure Integrated Controller.
I need to demonstrate I, the issuer, can not know the private key without colluding with the user to obtain it, even ...
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1st round attack on rc4
I'm trying to implement the 1st round attack on RC4 stream cipher according to Attacks on the RC4 stream cipher. For now I am interested in section 4.2 Attack on other key bytes. It works really fine ...
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Safe p-value for NIST randomness test with small sample size
In this journal paper related to physically unclonable function (PUF) [1], the authors used NIST 800-22 test to check if the bitstreams generated by their PUFs are random, which is described as ...
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Conditions on a cryptographic hash function for Randomness Extraction
Assume we want to transform semi-random $n$-bit inputs into shorter $k$-bit outputs computationally indistinguishable from uniformly random bit strings, and there is (in some sense, to be specified) ...
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Do all numbers have all the same chances to be returned using a CSPRNG?
Given a range of numbers, e.g. [1, 2^256], does each number have the same chances to be picked by a CSPRNG, which are 1 in 2^256?
My concern is that truly random number generators do have this feature,...
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Algorithm used to generate a BitLocker recovery key
I know exactly how a generated BitLocker recovery key works and I can write a code to brute-force it.
How is the recovery key generated though?
I could think of some answers:
it is generated using an ...
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Is it safe to initialize a random number generator with MD5 for pixel selection in image steganography?
This question is related to "Is it safe to initialize a random number generator with MD5?".
But in the context of steganography we don't know which pixels have been selected to hide ...
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Is it safe to initialize a random number generator with MD5?
The MD5 algorithm is no longer considered secure for most applications of a hash algorithm. However, is it safe to initialize a PRNG via a password?
If it is not, how could it be exploited?
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Does a pseudo-random number have the same security as its SHA digest message?
Is a random number generated by a CSRNG equivalently secure as the SHA hash of that number? I know that RNGs generate numbers that look random, and aren't necessarily random. For example, in a range ...
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How to create a CSPRNG seed that can be used to shuffle a deck of cards
I want to generate a seed using CSPRNG. I then want to shuffle a standard pack of playing cards (52) using said seed, however, I want the shuffle to be accurate enough that it covers all the possible ...
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Where can I find a comprehensive guide to running the NIST SP800-90B_EntropyAssessment?
I am already using the 2 they suggest :
https://github.com/usnistgov/SP800-90B_EntropyAssessment https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-90B.pdf
but, here is where I run into ...
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exact meaning of ntup in dieharder tests
I'm working with the dieharder package to test a PRNG, but I don't quite understand the ntup parameter.
I get that the ntuple should be a set of consecutive bits. ...
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Hash function adapted to work as bactracking resistant PRNG
Let's consider PRNG which is updating its state by using some cryptographically secure hash function. So it takes some input, returns output and this output is a new input. And so on.
Of course there ...
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Bactracking resistance PRNG - real world usage
I read about bactracking resistance:
http://cs.yale.edu/publications/techreports/tr1466.pdf
https://arxiv.org/pdf/1810.02227.pdf
https://www.schneier.com/wp-content/uploads/2017/10/paper-prngs.pdf
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