Detailed explanation of examples of methods to prevent hotlinking in PHP-PHP Tutorial-php.cn

This article mainly introduces the method of anti-hotlinking in PHP, and analyzes the related technologies and specific implementation techniques involved in PHP anti-hotlinking in the form of examples. Friends in need can refer to it

The details are as follows:

$_SERVER['HTTP_REFERER']acquisition situation

Note$_SERVER['HTTP_REFERER'] may not always be obtained, only It can be obtained under the following circumstances:

1. The circumstances under which HTTP_REFERER can be obtained are as follows:

1. Use
2 directly. Form submitted with Submit or(POST or GET)
3． Form submitted using Jscript (POST or GET)

2. The following situations cannot be obtained:

1. Link from Favorites
2. Click "Home" or the customized address
3. Use Jscript's location.href or location.replace()
4． Directly enter the address
5 in the browser. <%Response.Redirect%>
6． <%Response.AddHeader%> or Go to
7． Use XML to load the address

strrposFunction explanation:

strrpos - Calculate the position of the last occurrence of the specified string in the target string

Description

int strrpos (string $haystack, string $needle [, int $offset = 0])Returns the last occurrence of needle in string $haystack Numeric location.

$haystack	Find in this string.
$needle	If needle is not a string, it will be converted to an integer and treated as a sequential value of characters.

Return value

Returns the position where needle exists. If not found, returns FALSE.

Hot link determination code: asd.php

'; } else{ header("Location:warning.php");//跳转页面到warning.php //echo $_SERVER["HTTP_REFERER"]; } } else { header("Location:warning.php"); } ?>

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warning.php

 倒链

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Anti-hotlink verification code

    Insert title here 
  验证防盗链

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The above is the understanding principle

Generally configure the server to prevent hotlinking, such as nginx configuration access

(gif|jpg|jpeg|png|bmp|swf)White list of other files

The specific configuration can be searched on Baidu

Related recommendations:

NginxAnti-hotlinkingAnd Nginx access control and Nginx parsing php configuration

How about PHP Implementanti-hotlinkdetailed explanation

php crackanti-hotlink

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