<?php

$json = '{"token":"blablabla"}';
$salt = "21x1231";

$code = json_decode($json, true);
$token = $code->token;
$hash = strtolower(md5($token.salt)); 
echo 'url?param='.$token.'&tok='.$hash;
echo PHP_EOL, PHP_EOL;

$code = json_decode($json);
$token = $code->token;
$hash = strtolower(md5($token.$salt)); 
echo 'url?param='.$token.'&tok='.$hash;