cSHAKE from command line

[Robert Moskowitz]

the Fedora user list provided:


==========

It looks like the package "python3-pycryptodomex" might have you want.
https://pycryptodome.readthedocs.io/en/v3.15.0/src/introduction.html

==========

So at least I can get cSHAKE within python.



On 4/17/23 08:40, Robert Moskowitz wrote:
> I am looking to generate a cSHAKE output via the openssl command line.
>
> In: 
> https://wiki.openssl.org/index.php/Command_Line_Utilities#Generating_a_File_Hash
>
> I see I can generate a SHAKE128 hash by:
>
> openssl shake128 stringtohash.dat
>
> NIST SP800-185 defines cshake128 as:
>
> cSHAKE128(X, L, N, S) = KECCAK[256](bytepad(encode_string(N) || 
> encode_string(S), 168) || X || 00, L)
>
> In my usage, "N" will be a null string, but "S" will have a value.
>
> and FIPS202 defines SHAKE128 as:
>
> SHAKE128(M, d) = KECCAK[256] (M || 1111, d)
>
> Why 202 uses "M" & "d" and 185 uses "X" & "L" is beyond me, but eh.
>
> I don't see how to get from one to the other.  Or maybe I am just 
> missing the cSHAKE option, but the openssl wiki does not seem to have 
> any reference to cSHAKE.
>
> thanks for the help.
>
>