New answers tagged rsa
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Reproducing RSA GCD attack (common factor) - real world certificates
There is a 900,000 domain-key database for DKIM RSA public keys for email security at registry.prove.email, that no one to my knowledge has run batch-gcd on yet. There may be some reused keys between ...
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Where can I download a database of RSA keys?
There is a 900,000 domain-key database at registry.prove.email, that no one to my knowledge has run batch-gcd on yet. There may be some reused keys between websites however, so total unique keys may ...
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Confused about use of Euler totient function in RSA
why $x^{ed} \mod n =x$ implies that $ed\mod \phi(n)=1$?
Answer: it doesn't.
On the other hand, if $\forall x: x^{ed} = x \pmod n$, that does imply that $ed \bmod \text{lcm}(p-1, q-1) = 1$.
If $ed \...
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Accepted
Why is 65537 always coprime to φ(N) in RSA?
$65537$ is not always coprime to $\varphi(N)$ in RSA1. But it often is, because:
It often2 is chosen $e=F_4=2^{(2^4)}+1=65537$ in RSA, and then the requirement3 that $e$ is coprime to $\varphi(N)$ ...
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Why is 65537 always coprime to φ(N) in RSA?
There is no known weakness for any public exponent for RSA, as long as the public exponent $e$ is relatively prime to $\varphi(n)$ and the proper padding scheme is used. Fermat's primes are preferable ...
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Why is 65537 always coprime to φ(N) in RSA?
The choice of 65537 is popular because it is a prime number $2^{16}+1$. There might be more reasons, but ones that come to mind are:
It's prime, but not a large number so it's easy on the division ...
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How often do hard-to-factor numbers occur?
If we define "hard to factor" numbers as semi-primes with both factors greater than $2^{\frac k4}$. The average prime gap at this size is < $k\ln(2)$, so for each prime $p_1$ in $[2^{\...
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Creating multiple "public" keys from one private key
It sounds like you are talking about key derivation, for example Hmac-based key derivation (HKDF). You can derive a private key from a known (private) seed or from another private key, creating a ...
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How often do hard-to-factor numbers occur?
As I commented already, the easier problem of finding many hard-to-factor numbers in the (big) interval $[2^k, 2^{k+1}]$ is relatively easy, as this is exactly what an RSA key generation has to do: ...
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Public proven methods to generate SSH key from pass phrase?
I'm assuming that you're talking about SSH private keys. These are just files storing secret keys used in the connection protocol. It is, for example, possible use RSA keys with SSH.
So now the ...
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How often do hard-to-factor numbers occur?
Integers that are easy to factor are primes, integers with small factors, where you can remove all small factors and the remaining number is easy to factor. Plus special cases, like semi primes that ...
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Accepted
Deriving the RSA private key
Is there any security issue with my approach?
Well, no, there doesn't have to be.
One approach would be to seed a cryptorng with $P, Q, salt$, and then use the output bits of your cryptorng as the ...
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