Looking for an linux (or windows) offline SHA-256 binary calculator

[Zellko]

Hello guys,

Do you know any SHA-256 binary hash calculator, like this online one:

https://cryptii.com/hash-function

The goal is to create my own seed from 256 bits generate with a dice, then to the binary sha-256 hash in order to find the last 8 bits (checksum) for my seed.

For obvious security reasons, I want to use a old, offline computer using tails live-cd.

Thanks,

[achow101]

You can use OpenSSL's hashing command. Or you can write your bytes to a file (with a hex editor or something) and hash the file using sha256sum which comes standard in most linux distributions.

[RGBKey]

If you're using Windows and you'd rather not have to install any additional software, there's a certutil command available to calculate hashes (among other things).

To calculate a hash, do  certutil -hashfile filename algorithm

For example, certutil -hashfile image.png SHA256

The available hash algorithms are MD2, MD4, MD5, SHA1, SHA256, SHA384, and SHA512.

[rpstatic]

I am not sure about tails, but under Ubuntu you can just use

Code:

echo -n "Message" | sha256sum

Don't forget the "-n" otherwise you will hash your message including a newline.