PHP Manual: Create a password hash using OpenSSL's Argon2 implementation

Description

string openssl_password_hash(string $algo, string $password, array $options = [])

Creates a password hash using OpenSSL's Argon2 implementation. This is an alternative to password_hash that uses OpenSSL as the backend, which may offer hardware acceleration on some platforms.

This function is only available when PHP is compiled with OpenSSL support that includes Argon2 (HAVE_OPENSSL_ARGON2).

Parameters

algo

The password hashing algorithm. Supported values: "argon2id" and "argon2i".

password

The user's password.

options

An associative array of options. Supported keys:

memory_cost - Maximum memory (in KiB) that may be used to compute the hash
time_cost - Maximum amount of time it may take to compute the hash
threads - Number of threads to use for computing the hash

Return Values

Returns the password hash as a string.

Errors/Exceptions

Throws a ValueError if algo is not one of the supported values ("argon2i" or "argon2id").

Throws an Error if the hashing operation fails for an unknown reason.

Changelog

Version	Description
8.4.0	Function added.

Examples

Example #1 openssl_password_hash example

<?php
$hash = openssl_password_hash('argon2id', 'my-secret-password');
echo $hash;
?>

The above example will output something similar to:

$argon2id$v=19$m=65536,t=4,p=1$c29tZXNhbHR2YWx1ZQ$hashvalue...

Example #2 openssl_password_hash with custom options

<?php
$hash = openssl_password_hash('argon2id', 'my-secret-password', [
    'memory_cost' => 65536,
    'time_cost'   => 4,
    'threads'     => 1,
]);
?>

openssl_password_hash