undefined constant PASSWORD_ARGON2ID

Hi @onyx808,
PASSWORD_ARGON2I support is only available on PHP 7.3 and future versions. You can use PASSWORD_ARGON2I if you have PHP 7.2 or later.

@ayeshrajans Im on PHP Version 7.2.9, setting “define(‘WP_PASSWORD_HASH_ALGO’, PASSWORD_ARGON2I);”

Still gives error.

( ! ) Warning: Use of undefined constant PASSWORD_ARGON2I – assumed ‘PASSWORD_ARGON2I’ (this will throw an Error in a future version of PHP) in /wp-config.php on line 85

I see. It looks like your PHP setup is not compiled with Argon2 support.

Most of the common distros have this enabled, but if you compile PHP yourself, please make sure you have ./configure --with-password-argon2 step to enable Argon2 support.

May I know your OS, whether you compiled PHP yourself, or the repo you used to get PHP binaries from?

You are right, I was testing on my local environment with php 7.2 installed using brew…

for anyone having the same issue see below:

To check whether PHP is compiled with Argon2:

? php -r 'print_r(get_defined_constants());' | grep -i argon
    [PASSWORD_ARGON2I] => 2
    [PASSWORD_ARGON2_DEFAULT_MEMORY_COST] => 1024
    [PASSWORD_ARGON2_DEFAULT_TIME_COST] => 2
    [PASSWORD_ARGON2_DEFAULT_THREADS] => 2
    [SODIUM_CRYPTO_PWHASH_ALG_ARGON2I13] => 1
    [SODIUM_CRYPTO_PWHASH_ALG_ARGON2ID13] => 2
    [SODIUM_CRYPTO_PWHASH_STRPREFIX] => $argon2id$

If you don’t get the above output, either re-compile PHP 7.2+ with the flag –with-password-argon2 or:

Ubuntu

? sudo add-apt-repository ppa:ondrej/php
? sudo apt-get update
? sudo apt-get install php7.2 or php7.3

macOS

? brew update
? brew install php

Awesome, thanks a lot for this helpful information @onyx808.