keccak | SHA-3 Keccak implementation in C

You can't convert the hash value back to the original string. The hash function is created in a way that it is infeasible to convert the hash value back to the original string.

The easist way to make it working is to patch webpack.config.js generated by Angular CLI.

Create web3-patch.js file in root folder of your app.

I found my error. My jest.config.ts had src in the moduleDirectories because I configured Next.js to support absolute imports.

You can achieve SHA-3 256 Hashing with a SQL Server CLR integration

There is a project on GitHub that has most of the work done for you already and you could easily add SHA3 support to it.

https://github.com/sedenardi/sql-hashing-clr

There is no way of SHA3-256 hashing with pure dotnet core. I recommend you make use of BouncyCastle library (https://www.bouncycastle.org/csharp/index.html) that has a SHA3-256 support. There is a nuget library package that is a wrapper on top of BouncyCastle and could make SHA3-256 hashing relatively easy to achieve. https://www.nuget.org/packages/SHA3.Net/. You'll need to use this package and update HashUtil.cs

Pre Req: Build CLR .dll

openssl pkeyutl -sign -inkey ecprivkey.pem is entirely correct.

I would assume for the large my-very..-long-digest it should return larger output (because it should take the input as-is without shortening (hashing).

You assumed wrongly. An ECDSA signature mathematically consists of two integers (r,s) in the range 1 to the order of the curve subgroup; it is completely unaffected by the size of the hash used as (or on) the input. It is recommended to use a hash whose size matches the subgroup -- e.g. SHA256 (or your Keccak256) with P-256 aka secp256r1 -- because otherwise if the hash is too large it is truncated or if too small it is padded and either reduces security.

The same is true for DSA, and mostly for RSA -- for RSA the signature is always the size of the RSA key, and an encoded-and-padded hash smaller than the RSA key is padded, but a too-large one is rejected as an error. (This is very rare, because RSA keys below 2048 bits are no longer considered acceptably secure for use, and no one uses hashes that big.)

The size of an ECDSA signature representation -- or encoding -- can vary and there are several different standards. OpenSSL always uses the ASN.1 SEQUENCE of INTEGERs shown in rfc3279 2.2.3. So does the standard SunEC provider in Java, and so does the BouncyCastle provider in Java by default. The length of the ASN.1 encoding depends, usually only slightly, on the values of the two integers which as you correctly note are controlled by a random value (k) and thus effectively pseudo-random numbers themselves. See (cross) https://crypto.stackexchange.com/questions/33095/shouldnt-a-signature-using-ecdsa-be-exactly-96-bytes-not-102-or-103 and https://crypto.stackexchange.com/questions/44988/length-of-ecdsa-signature

The Bouncy provider also supports '{hash}with{PLAIN-,CVC-}ECDSA' algorithms which do the same mathematical signature but use the simpler representation defined by P1363, simply two (unsigned bigendian) integers of fixed size (equal to the subgroup order size) concatenated. JWS also uses this representation. Finally, the Bouncy LWAPI which you showed returns or takes BigInteger[] -- the mathematical value -- and leaves the encoding and decoding up to you.

It seems Botan support for building Android binaries on Windows hosts is limited. You will have to use dark magic to make this work.

The build process consists of two phases, the configuration phase and the make phase.

The Android-specific instructions in the documentation you linked do not cover the whole build process, only the configuration phase. For the make phase, you then have to follow the Windows-specific instructions (link).

You will need the following binaries, adjust the paths to your machine:

• clang++ (note the .cmd at the end): C:\Development\android-ndk-r19c-windows-x86_64\android-ndk-r19c\toolchains\llvm\prebuilt\windows-x86_64\bin\armv7a-linux-androideabi28-clang++.cmd

• ar: C:\Development\android-ndk-r19c-windows-x86_64\android-ndk-r19c\toolchains\llvm\prebuilt\windows-x86_64\bin\arm-linux-androideabi-ar.exe

In the Botan folder, run the configure command:

Module output's can only be connected to net types in Verilog and roundreg[1] is not a net. If possible, you can declare roundreg as wire [23:0] roundreg [1599:0] instead, though that might affect how the rest of your code works. Note that if you can use SystemVerilog, you can avoid these complexities, and use the logic type instead.

You can also look at this question to see how to infer block RAM for FPGA designs: How to initialize contents of inferred Block RAM (BRAM) in Verilog

str is already decoded and you are trying to decode it, which is already decoded. but if you really want to decode it, you should encode it, and then decode it again. i don't recommend it.

i recommend you to use binascii. note that the input string should be a byte-like object.

I can debug and solved the problem and share the solutions with you