login |
why we choose logins and credentials?
the Logins and credentials are used to define the user for uniqueness and experience the services fully.credentials are used for restricting the access to the other users and privacy.
user-login-representation |
what happens when You Enter a Logging system?
Generally when you enter a Username & Passwords through a Form.they are considered as input from users and they are being travelled to Server side validation.validation is the important step in a Login system.First it checks and clean the input values to avoid injecting database.then they are appended through a Query statement and if the process gets success,You are redirected to another page.If the process fails it stands in same page.
here i provide You a Simple codings from PHP & MYSQL:
config.php:
<?php
$mysql_hostname = "localhost";$mysql_user = "username of mysql account";$mysql_password = "password";$mysql_database = "your database name";$bd = mysql_connect($mysql_hostname, $mysql_user, $mysql_password) or die("Could not connect database");mysql_select_db($mysql_database, $bd) or die("Could not select database"); ?>
$mysql_hostname = "localhost";$mysql_user = "username of mysql account";$mysql_password = "password";$mysql_database = "your database name";$bd = mysql_connect($mysql_hostname, $mysql_user, $mysql_password) or die("Could not connect database");mysql_select_db($mysql_database, $bd) or die("Could not select database"); ?>
create config.php file and keep it in Your web server directory.
create a table in your database:
CREATE TABLE IF NOT EXISTS `login` (`id` int(11) NOT NULL AUTO_INCREMENT,`username` varchar(500) NOT NULL,`password` varchar(500) NOT NULL, PRIMARY KEY (`id`)) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
Run sql query to generate the table.
<!DOCTYPE HTML>
<html>
<head>
<title>Login System</title>
</head>
<body>
<h1>Login Form</h1>
<?php
if(isset($_GET['msg']))
{
$msg=$_GET['msg'];
echo '<p><font color="red">';
echo $msg;
echo '</font></p>';
}
?>
<form action="verify.php" method=POST>
<label for="username">Username</label>
<input type="text" name="username" id="username" placeholder="username"><br>
<label for="password">Password</label>
<input type="password" name="password" id="password" placeholder="password"><br><br>
<input type="submit" value="Submit">
</form>
</body>
</html>
save this code as index.php file in same directory.
<?php
$username=$_POST['username'];
$password=$_POST['password'];
$query="select * from user where username='".$username."'";
$result=mysql_query($query);
$records=mysql_fetch_array($result);
if($records)
{
if($password==$records['password'])
{
session_start();
$_SESSION['username']=$records['username'];
$_SESSION['userid']=$records['id'];
header('Location: home.php');
}
else
{
$msg="Password Incorrect";
header('Location: index.php?msg='.$msg);
}
}
else
{
$msg="Username Incorrect";
header('Location: index.php?msg='.$msg);
}
?>
home.php:
<?php
if(session_start())
{
$username=$_SESSION['username'];
$userid=$_SESSION['userid'];
echo "You Are Logged IN -<b>".$username."</b> and your ID is -<b>".$userid."</b>";
?>
<a href="logout.php">Log out </a> <?php
}
else
{echo "Access Denied";
}
?>
logout.php:
<?phpthis provides you to access the home.php.
if(session_destroy()){ echo "logged out successfully!"; }
?>
if user bypass the login! he will be noted as Access Denied.
thus tutorial gives you a start up for login system and You can see advanced logins like php self() using functions in my next post,which is reliable now as secured.
if you feel free comment below.
HEY NICE ONE shiva BUT! THERE IS A SLIGHT BUG!
ReplyDeleteIN FORM TAG POST MUST BE IN "POST"
-@aishu
yeah correct aishu!
Deleteand change the querystatement user to login!
$query="select * from login where username='".$username."'";
$result=mysql_query($query);
quite useful for beginers but contains many vulnerabilities .....
ReplyDeletepls post abt validating user input....
ReplyDeletethanks,
naren.
your explanation towards the login and credentials was awsome..this shows your understanding capablity of needs in environment!
ReplyDelete- ankush
good work ! this gave me a start up! pls post a secure login system in future
ReplyDelete-Satish