Latest Crypto related questions

If I have a known plaintext and ciphertext pairs and 2 unknown keys of length 24 bits. (Assume encryption method is unknown)

9acb0442f0c5341e 035a85c5772da926
aa209b8e700e0976 f1849958b47fec38
6cb50b02afd3a30c 4e48ca11ee429960
10cd96722811a558 0a18dd10a6b31c5c
18d2fe904d088f48 f84950f2d18dc4e8
83e4f98dd04ab55f 4dc9a896a1dd3a99
36d9ff456172bfe3 ea626b82da337f24
516c42b078092a35 05d5757be9fca1e7

The fir ...

It looks like on BFV, I can always relinearize and keep doing operations on numbers. However, on CKKS, when we multiply 2 values together, their scale gets multiplied also. So we end up having to re-escale by doing modulus switching (taking off one of the primes of the RNS representation of the ciphertext):

The number of primes limits how many rescalings can be done, and thus limits the multiplicative d ...

I saw a paper said RC6 cipher is weak and weakness cause of using 'SINGLE CLASS OF WEAK KEYS' What is that mean? and could we solve this problem ?

Thank you.

i have a function transferWithData(address to, uint256 amount, bytes data) it basically transfer ERC20 token but it has an additional 'data' field, in order to inject a certificate generated off-chain by an issuer.

Certificate contains:

1. The function ID which ensures the certificate can’t be used on an other function.
2. parameters which ensures the input parameters have been validated by the issuer.

1. Scenario

Suppose that we have a source that is generating one random value per, say, minute. So we have random value $x_1$ in $1$st minute, $x_2$ in $2$nd minute, $\ldots$, $x_n$ in the $n$th minute, and so forth.

The distribution of values $x_1, x_2, \ldots$ is not entirely uniform random, but follows the following rule: for any $i \ge 1$, $x_i = (y_i, y_{i+1})$, where, $y_i$ is the unique ident ...

Given a keyed pseudorandom function $f: S \times X \rightarrow Y$, where $S$ is the space of secret keys, $X$ is the input domain, and $Y$ is the range, the pseudorandom property says that given any secret key in $S$ the uniform distribution over $Y$ is indistinguishable from the distribution of $f(X)$.

Am wondering, does this property imply also the following:

Let $f: S \times X \rightarrow Y$ b ...

I'm reading FIPS 197 (AES) to try and understand how the algorithm works but I don't yet have answer for are these two questions:

1. I see the 256 byte s-box for substituting during the rounds. Do the values in this 256 byte table get updated or is it a static table for the whole transformation?
2. In key expansion, I see that the key is expanded based on the amount of rounds there are which determined by t ...

I am reading Fast and Secure Three-party Computation: The Garbled Circuit Approach And in the introduction section it said that:

the round complexity of these protocols is proportional to the circuit-depth of the computation being performed

What does this exactly means? Why does Yao's garbled circuit does not have this kind of issue?Thanks in advance!

For El-gamal encryption, safe prime p is used such that p = 2q+1. However, can someone explain to me in simple terms why we would need in this context a large order of G and how it will contribute in making g^ab more secure such that a & b could be 0btained via solving for discrete logarithm problem.

Based on Wikipedia, using p = 2q+1 denotes that order of G is is 2 and q and that "g is then  ...