Erro De Lógica

[Eric Freitas]

bom pessoal... se lerem meu código verão q num é dificil o que eu quero fazer..

mas to com um probleminha na lógica do php.. se alguém puder me ajudar a achar o erro agradeço..

INDEX.PHP
<?php
    session_start();
    $_SESSION['username'] = $_POST['username'];
    $_SESSION['passwd'] = $_POST['senha'];
    require_once'funcoesUser.php';
    echo'<link rel="stylesheet" type="text/css" href="estilo.css" />';
    if(empty($_GET['ins'])){
        verUser($_SESSION['username'],$_SESSION['passwd']);
    }elseif(!empty($_GET['ins'])){
        $_ins = $_GET['ins'];
        //-----------------------------------------------------------------------------------------------------
        switch ($_ins){
        case 1:
            echo'<div class="meio">';        
            echo'<form id="form1" name="form1" method="post" action="'.$_SERVER['PHP_SELF'].'?ins=2">';
            echo'<table width="150" border="0" cellspacing="0" cellpadding="0">
                      <tr>
                       <td colspan="3"><div align="center"><strong>Registrar Usu&aacute;rio </strong></div></td>    
                 </tr>    
                    <tr>
                      <td>Username:</td>
                      <td>&nbsp;</td>
                      <td><input name="username" type="text" id="username" size="15" maxlength="15" /></td>
                </tr>
                <tr>
                      <td>Password:</td>
                      <td>&nbsp;</td>
                      <td><input name="senha" type="password" id="senha" size="15" maxlength="15" /></td>
                </tr>
                <tr>
                      <td colspan="3"><div align="center">
                           <input name="Enviar" type="submit" id="Enviar" value="Enviar" />
                           <input name="Resetar" type="reset" id="Resetar" value="Limpar" />
                      </div></td>
                </tr>
                  </table>
                </form>';
            echo'</div>';
            break;
        case 2:
                echo'<div class="meio">';
                $_user = $_POST['username'];
                $_pass = $_POST['senha'];
                if(strlen($_pass)>15 ||strlen($_pass)<8){
                    echo'Sua senha deve conter mais que <font color="red">8</font> e menos q <font color="red">15</font> caracteres';
                    echo'<META HTTP-EQUIV="Refresh" CONTENT="5;URL=?ins=1">';
                }
                require_once'conectaBanco.php';
                $_sql = mysql_query("INSERT INTO tp_usuario (username,passwd,permissao) VALUES ('$_user','$_pass','0')") or die('Erro de query');
                if($_sql){
                    echo'Dados incluidos com sucesso!';
                    $_SESSION['username'] = $_POST['username'];
                    $_SESSION['passwd'] = $_POST['senha'];
                    verUser($_POST['usename'],$_POST['senha']);
                    echo'<META HTTP-EQUIV="Refresh" CONTENT="5;URL=?acao=0">';
                }
                echo'</div>';
                break;
                default:
                    echo'div class="meio">';
                    echo'Operação inválida';
                    echo'</div>';
                    break;
        }    
    }elseif(!empty($_GET['acao'])){
        
    //------------------------------------------------------------------------------------
        switch($_GET['acao']){
            case 0:
            echo'<div class="tabela">';
                echo'<h1>Operador de tramitações</h1>';
                echo'</div>';
                break;

            case 1:
                if(verUser($_POST['username'],$_POST['senha'])==true){
                    
                }else{
                    echo'div class="meio">';
                    echo'Usuário e/ou senha inválidos';
                    echo'</div>';
                }
                break;
            default:
                echo'<div class="meio">';
                echo'Operação inválida';
                echo'</div>';
                break;
            
        }
    }
?>
FUNCOESUSER.PHP
<?php
    function verUser($_login,$_senha){
        require_once'conectaBanco.php';
        $_sqlVerifica = mysql_query("SELECT * FROM tp_usuario") or die('Erro na query');
        $_sql = mysql_query("SELECT * FROM tp_usuario where username = '$_login' and passwd = '$_senha'") or die('Erro na query');
        $_linhas = mysql_num_rows($_sqlVerifica);
        if($_linhas==0){
            echo'<META HTTP-EQUIV="Refresh" CONTENT="1;URL=?ins=1">';
        }elseif(!$_sql){
            return false;
        }else{
            return true;
            echo'<META HTTP-EQUIV="Refresh" CONTENT="1;URL=?acao=1">';
        }
        }
    
?>