HOW TO:Create Secure Login With Simple PHP ?

Here is a simple example for creating a secure login page with PHP which will help you to safe authentication. Here, cookies are not used because of preventive measure against cross-side scripting. The back-end used is MySQL. So, you should have knowledge of MySQL and database as well.

Database

Make a table called login. Use SQL below to create a table of login.

CREATE TABLE login (
user_name varchar(20) NOT NULL default '',
user_pass char(32) binary NOT NULL default '',
PRIMARY KEY (username)
);

CREATE TABLE login (

user_name varchar(20) NOT NULL default '',

user_pass char(32) binary NOT NULL default '',

PRIMARY KEY (username)

);

HTML

&lt;form action="login.php" method="post"&gt; &lt;input name="user_name" size="18" type="text" /&gt;
&lt;input name="user_pass" size="18" type="text" /&gt;
&lt;input name="submit" type="submit" value="Login" /&gt;
&lt;/form&gt;

</form>

Form

if(count($_POST) &amp;gt; 0) {
 $user_name = htmlspecialchars($_POST["user_name"]);
 $user_pass = htmlspecialchars($_POST["user_pass"]);
 
 $sql = "SELECT user_name,user_pass FROM login
           WHERE user_name=\"$user_name\"
            AND    user_pass=\"$user_pass\"";
 
 $rs = mysql_query($sql);               //execute the query
 if(mysql_num_rows($rs)	==	1)  {
 	// username and passwords exists in database
       //other codes
 }
 else {
 	//invalid username of password
 	//redirect to login page
 
 	header("Location: login.php");
 }
 
}

if(count($_POST) &gt; 0) {

$user_name = htmlspecialchars($_POST["user_name"]);

$user_pass = htmlspecialchars($_POST["user_pass"]);

$sql = "SELECT user_name,user_pass FROM login

WHERE user_name=\"$user_name\"

AND user_pass=\"$user_pass\"";

$rs = mysql_query($sql); //execute the query

if(mysql_num_rows($rs) == 1) {

// username and passwords exists in database

//other codes

}

else {

//invalid username of password

//redirect to login page

header("Location: login.php");

}

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