creation of (real or pseudo) random numbers (or bits).
2
votes
1answer
170 views
Conforming Randomness To An Alphabet
Imagine that we're trying to create a function to generate a random string conforming to a user-supplied alphabet. That way, users can generate random strings with given characters. Something like:
...
2
votes
1answer
212 views
server side Javascript security
It is accepted that the javascript library lacks the ability to create an adequate PRNG. My understanding that this was mainly due to the limits of a sandboxed browser enviroment that javascript ...
2
votes
2answers
132 views
Does a hash function in chaining mode or in counter mode make a better pseudo-random number generator?
I have two pseudorandom generators:
$f_1$ takes a random seed $l_0||r_0$ $\in \{0,1\}^{160}$ as input and outputs $r_1||r_2|| \dots ||r_k$, where $l_i||r_i = \operatorname{SHA-1}(l_{i-1}||r_{i-1})$ ...
2
votes
1answer
216 views
Webcam random number generator
I have a question about random number generators.
I have read from a real random number generator, based on a webcam ("randcam"). My problem is, that I do not really understand how the generation of ...
2
votes
1answer
115 views
Seed a PRNG with random data and a password
I'd like to combine a random key file with a password to generate a secure seed for a CSPRNG. The key file is assumed to have very high entropy, but the password will be whatever the user provides. ...
2
votes
1answer
296 views
Linear Feedback Shift Register Taps
Linear feedback shift register tap charts are availale for registers of length 3 to 168. Does anyone have a chart for register lengths from 168 to 256 or beyond? Thank you.
2
votes
2answers
522 views
Using an RSA private key simultanously as an AES encryption key to generate random numbers?
Currently I'm implementing a PRNG for an embedded system. Using the RFC 4086 I've decided to use the X9.17 - to be more specific the succesor X9.31- standard to implement my PRNG. X9.17 uses DES, but ...
2
votes
0answers
113 views
Odds of false error detection in a randomness test using the chi-squared test?
Common Criteria classifies the requirements for true Random Number Generators, and specifies how these should be tested against failures (these can occur accidentally, or following deliberate attack, ...
2
votes
3answers
221 views
Endless PRNG from PRNG with specific stretch?
Every definition of pseudorandom generator that I've seen says it takes n-bit strings and gives poly(n)-bit strings.
Is there a proof that if there is such a pseudorandom generator then there is a ...
1
vote
1answer
1k views
Cryptographic security of PHP mt_rand() function using Mersenne Twister algo
At stackoverflow this question has been asked. It uses additional random entropy and a hash method (among others) to try and create a cryptographically secure pseudo-random number generator for PHP. ...
1
vote
2answers
129 views
True random numbers generated by sensors
Is using sensor raw data a good way of generating true random numbers? I mean using an IPhone's gyro/accelerometer raw output as a base for generating an array of true random numbers.
1
vote
1answer
99 views
Can A PRNG Be Used To Generate Multiple Private Keys for ECDSA?
Suppose Alice seeds a cryptographically strong Pseudo Random Number Generator with a truly random number, and keeps it secret. Alice then uses the output of the PRNG to generate several 256-bit ...
1
vote
2answers
169 views
How do I demonstrate that a PRNG not designed for cryptography is not suitable for generating passwords?
This is a replication of this question on Stack Overflow. There's class Random in .NET runtime which is designed for use as a cheap fast source of pseudo-random ...
1
vote
2answers
72 views
GGM PRG construction: Why do we need to change keys all the time with underlying PRG
When constructing a PRF that has n bit input using the GGM PRG, why do we always have to recursively run the PRG using its previous output as a seed key n times. Instead, why don't we run the PRG n ...
1
vote
1answer
111 views
Why does Fortuna (RNG) require entropy sources to specify accumulator pool?
Re-reading my copy of Cryptography Engineering for the holidays, I was struck by the following question about the Fortuna RNG:
Why require an entropy source specify which pool a random event should ...
1
vote
1answer
147 views
Generating a cryptographically secure, many-time use, symmetric encryption key
I need to generate a 256 bit encryption key described by the adjectives in the title. Currently I intend to create the key using this RNG.
Is this a secure manner of creating the key, given that it ...
1
vote
2answers
98 views
CSPRNG in JavaScript using Audio and Video
I ported GnuPG to Javascript using Emscripten (not released yet).
Now I need a good replacement for /dev/random//dev/urandom.
...
1
vote
2answers
101 views
random number generator 10-side dice alternative
A lot of sites like this one Here, refer to 10-side dice to generate random number for otp. I was thinking about new ways to generate random numbers,letters and passwords. here what I got.
to ...
1
vote
3answers
220 views
Entropy of system data - use all and hash, or trim least significant bits?
I'm working on a background entropy collector for key generation that monitors hardware and produces an entropy pool.
Here's my list of sources:
Mouse position
Keyboard timings (i.e. time between ...
0
votes
1answer
103 views
Is this scheme a provably fair random number generation?
I have thought up a method for generating random numbers between a client and a server which I hope is fair:
The client and server decide on a range in advance, $0$ trough $n-1$.
The server ...
0
votes
2answers
341 views
Are mouse movement coordinates useful as a seed for a RNG?
Is it good to use a mouse movement as a 64-bit random seed for a Pseudorandom Generator like AES in Counter Mode?
Should I only need to get the X and Y coordinates of the mouse movement?
0
votes
1answer
156 views
Cryptographically strong pseudo-random seq. generators
If a pseudo-random sequence generator is built so that it uses an n-bit seed and outputs a string that is of length x. Let's say one wants to generate a bit string of length y and uses the previous ...
0
votes
2answers
146 views
Generate random number which should depend on key
i want to generate random number for example from [1..100].
This algorithm which generates random number should work similarly like ("Linear congruential generator").
Here:
c - increment should ...
0
votes
1answer
64 views
Is there a problem with constructing a CSPRNG using MD5 or SHA1?
Is there any security concerns with building a CSPRNG using a broken hash function like MD5 or SHA1? The design is such that a CRC-like function is used for mixing entropy and MD5 is used as the ...
0
votes
0answers
100 views
Secure Pseudorandom Number Generators [closed]
Can anyone list the pseudo-random number generators used in todays stream ciphers that are considered secure or highly resistant to cryptanalysis?
-1
votes
1answer
93 views
Pseudo-random Number generation for Passwords
i want to know what is the best pseudo-random number generation algorithm for passwords? for example my scenario is I have to generate 5K pseudo-random bits from a user-supplied password(6 ...
-2
votes
1answer
62 views
Cryptographic Primitive Method
Is there any cryptographic primitive bijective (one-to-one and onto) function for creating cryptographic tools like symmetric encryption/decryption, Hash code generator, MAC, HMAC and Random number ...
-4
votes
1answer
352 views
128-bit Pseudorandom number Generator
Is there any 128-bit pseudorandom number generator available?
I tried the Blum Blum Shub Generator, but I can't produce a 128-bit pseudo-random number.
Maybe before I produce a 128-bit pseudorandom ...
