Implement ED25519 auth for mysqlnd

Description

Overview

Since MariaDB 10.4 (released ~5 years ago) introduced an authentication method called auth_ed25519 and still supported till now in the latest versions of MariaDB which is now 11.3, here's official to read more about auth_ed25519

Right now, all MariaDB supported versions are support auth_ed25519 which as I said, since MariaDB 10.4

The Problem

As this code of PHP 8.1.0 ( Located in https://github.com/php/php-src/blob/php-8.1.0/ext/mysqlnd/mysqlnd_auth.c#L1315-L1326 ) mentioned below that auth_ed25519 is not supported yet.

/* {{{ mysqlnd_register_builtin_authentication_plugins */
void
mysqlnd_register_builtin_authentication_plugins(void)
{
	mysqlnd_plugin_register_ex((struct st_mysqlnd_plugin_header *) &mysqlnd_native_auth_plugin);
	mysqlnd_plugin_register_ex((struct st_mysqlnd_plugin_header *) &mysqlnd_pam_authentication_plugin);
#ifdef MYSQLND_HAVE_SSL
	mysqlnd_plugin_register_ex((struct st_mysqlnd_plugin_header *) &mysqlnd_caching_sha2_auth_plugin);
	mysqlnd_plugin_register_ex((struct st_mysqlnd_plugin_header *) &mysqlnd_sha256_authentication_plugin);
#endif
}
/* }}} */

Also, here's what official MariaDB said about mysql_native_password:

The Requested Features

• Implement ED25519 authentication for MySQL Native Driver (mysqlnd)

More on this

• MariaDB - Authentication with ed25519
• MariaDB - Authentication Plugin - ed25519