Creating a SHA512 password hash on MacOS

One of the great tools that ships with every version of Linux is openssl. This piece of software allows you create hashes using many algorithms.

In a terminal, run openssl --help to list the supported hashing functions on your Linux system:

On Linux (e.g. Fedora):

openssl --help

blake2b512        blake2s256        md2               md4
md5               rmd160            sha1              sha224
sha256            sha3-224          sha3-256          sha3-384
sha3-512          sha384            sha512            sha512-224
sha512-256        shake128          shake256          sm3

MacOS also includes the openssl software, but it has fewer hashing algorithms available:

openssl --help
gost-mac          md4               md5               md_gost94
ripemd160         sha1              sha224            sha256
sha384            sha512            sm3               sm3WithRSAEncryption
streebog256       streebog512       whirlpool

Weirdly, when you try to run

openssl passwd -6 

On MacOS, it throws an error. SHA512 is a supported hashing function on MacOS, so it should work. Sadly, it does not. In order to use this command on MacOS, you need to feed the password into openssl like this (the <<< here indicates the input should be passed into the openssl function):

openssl dgst -SHA512 <<< YOUR_PASSWORD
120c223ffa2ac0662e79850dfc9c4d70ee0653d28aabb9e885c8a12580ca8a42c2f91f0bfedbccb6d6550d8ab6b1a8f0b19f2a5a88b7ec4ce148a75c83e37062

Another solution is to boot a Podman machine instance, ssh into it and use the openssl software that ships with Fedora CoreOS (Which is the vm machine that Podman runs in). I like this method, as it allows us to use openssl as the manpages dictate.

podman machine start &&
podman machine ssh

Now we can create our SHA512 hash by running the openssl passwd -6 and following the prompts:

The -6 here tells openssl we want a SHA512 hash

openssl passwd -6

Password:
Verifying - Password:
$6$0yip7Y5y1Cl8NFOf$rV6Mb3jdVafjWUO9Sj2mBCzenC62NsyB3s/pe8Qjs.aLakoPWJ8nprCtpq8ybg7O6WjONxYFsN2uQVpaDvg4J/

Podman machines on the M1 Mac start almost instantly, so using the software that ships with Fedora's CoreOS is a breeze.

Thomas - 31-03-2023