<?php
 
function encdec($t, $s){
 
    $secret_key = 'secret_key';
    $secret_iv = 'secret_iv';
 
    $output = false;
    $encrypt_method = "AES-256-CBC";
    $key = hash( 'sha256', $secret_key );
    $iv = substr( hash( 'sha256', $secret_iv ), 0, 16 );
 
    if( $t == 'e' ) {
        $output = base64_encode( openssl_encrypt( $s, $encrypt_method, $key, 0, $iv ) );
    }
    else if( $t == 'd' ){
        $output = openssl_decrypt( base64_decode( $s ), $encrypt_method, $key, 0, $iv );
    }
 
    return  $output;
}
 
$my_secret_enc =  encdec("e", "internal_XPto123");
echo $my_secret_enc ."\n";
 
$my_secret_dec = encdec("d", $my_secret_enc);
echo $my_secret_dec;
 

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