<?php

$usuariophp = $_POST['usuariojs'];
$senhaphp = $_POST['senhajs'];

$user = "SYSDBA";
$pass = "masterkey";
try{
    $str_conn = "firebird:dbname=localhost:teste;host=localhost";
    $lokos = new PDO($str_conn,$user,$pass);
}catch(PDOException $e) {
    echo "connection error.". $e->getMessage();
}

$stmt = $lokos->prepare("SELECT * FROM USUARIOS WHERE USUARIO = :usuario");
$stmt->execute(array(':usuario' => $usuariophp));
$dados = $stmt->fetchAll(PDO::FETCH_OBJ);

foreach ($dados as $row) {
    $id = "{$row->ID}";
    $usuario = "{$row->USUARIO}";
    $senha = "{$row->SENHA}";
    if($usuariophp == $usuario && $senhaphp == $senha){
        echo "ok";
    }else{
        echo "false";
    }
}
?>