Denie's Tech Blog » PHP

Simple Check IP with PHP

Denie — Mon, 15 Jun 2009 18:37:27 +0000

You can use below simple PHP scripting to check IP address

if(!empty($_SERVER["HTTP_X_FORWARDED_FOR"])){
echo “”.$_SERVER["HTTP_X_FORWARDED_FOR"].” via “.$_SERVER["REMOTE_ADDR"].”\n\n”;
echo “Your IP: “.$_SERVER["HTTP_X_FORWARDED_FOR"] . “
\n”;
echo “Proxy IP: “.$_SERVER["REMOTE_ADDR"] . “
\n”;
$ip = $_SERVER["HTTP_X_FORWARDED_FOR"];
}else{
echo “”.$_SERVER["REMOTE_ADDR"].”\n\n”;
echo “Your IP: “.$_SERVER["REMOTE_ADDR"] . “
\n”;
$ip = $_SERVER["REMOTE_ADDR"];
}
echo “Date Time: ” . date(”Y-m-d H:i:s”) . “
\n”;
?>

Mixing PHP and SSI

Denie — Tue, 24 Mar 2009 03:54:53 +0000

This information is ONLY relevant to PHP4 and Apache 1.3. (BUT possible can be work also in PHP 5.x and Apache 2.x ) We historically used PHP for all our web work. We have decided to migrate to ruby for lots of reasons for all our new web development but we still have lots of PHP stuff hanging around.

Background

We regularly mix PHP and SSIs for the following reasons:

Laziness – we have a lot of historic SSI stuff lying around and do not want to change it. We prefer evolution to revolution.
Appropriateness. Not all systems are good at everything. We find that conditionally selecting ‘lumps’ of code to deliver browser specific pages (see server side browser sniffing) is a lot cleaner and easier with SSI. That does not take away from either technology.

Nesting PHP and SSI

The rules go like this (PHP4 and Apache 1.3 – we understand that Apache 2 is more flexible but have not yet made the transition):

You can invoke SSI files from within PHP but must use the PHP virtual() function not include(). Variables set within PHP are NOT available to SSI so our favorite ‘wheeze’ of supplying last modified dates to a standard footer do not work.
You can include SSI files using the include virtual SSI directive but the SSI filename must have a .shtml extension even if the XBitHack is being used.
You cannot include PHP files using the include virtual SSI directive.
Variables set within the General Apache section (we use this technique for server side bowser sniffing) are available to both .php and .shtml files no matter how they are called.

Note: We would guess that the Apache environment for each type of file (.php and .shtml) is initialised to the same state as when the page is first called, whereas a nested .php files uses the same php environment and therefore reflects any dynamic changes.

Examples

The following is our standard level 1 template implemented in SSI first and then PHP.

SSI Version








Level 1 template

PHP Version








Cool Tools

  virtual ("/templates/styles.shtml");

  virtual ("/scripts/javascript.shtml");
?>



  virtual ("/templates/level_1.shtml");
?>

Notes:

You will notice that the styles, javascript and standard page navigation header use the PHP virtual() function because they contain SSI directives but the files are otherwise unchanged.
Our SSI ‘last modified’ date ‘wheeze’ for the footer does not work in a mixed PHP/SSI environment (because you cannot pass variables between PHP and SSI). Instead we have to create a “footer.php” file and set the variable ‘real_date’ using the PHP date() and getlastmod() functions. This file is invoked with the include() function because it is a standard PHP file. In ‘footer.php’ we just use ‘echo $real_date’ to place our last modified date in the output stream. Yes its simpler in PHP but now we have to maintain two versions of our standard footer.

Original

PHP configuration inside httpd.conf

Denie — Fri, 13 Mar 2009 13:53:34 +0000

How to set PHP error notice hidden in httpd.conf (vhost):


  ...
  php_flag display_startup_errors off
  php_flag display_errors off
  php_flag html_errors off
  ...

How to set individual php.ini in httpd.conf (vhost):


  ...
  PHPIniDir '/path/to/php/conf/php-foo.ini'
  ...

How to set individual PHPError.log in httpd.conf (vhost):


  ...
  php_flag  log_errors on
  php_value error_log  /path/to/site/PHPerror.log
  ...

Complete Information

Compiling PHP 5.2.x / cannot find -lltdl

Denie — Thu, 26 Feb 2009 10:35:11 +0000

When compiling PHP from source, some of the CentOS users reported that they getting errors like below:

/usr/bin/ld: cannot find -lltdl
collect2: ld returned 1 exit status

What you need to do, is just follow the below steps.

Verify that the libtool and libtool-ltdl packages are installed.
Symlink libltdl.so to libltdl.so.x.x.x

If libtool and libtool-ltdl already exist, you may go to Step Two.
Step One

[root@banzaibill ~]# yum install libtool-ltdl libtool

Now you have libtool installed. To check it out, do:

[root@banzaibill ~]# yum info libtool*

Step Two

PHP looks for the libltdl library only at /usr/lib/libltdl.so

The symlink to this file is not included in the libtool packages. Do below commands:

[root@banzaibill ~]# cd /usr/lib
[root@banzaibill lib]# ln -s libltdl.so.3.1.4 libltdl.so

And that’s it. PHP should configure and compile without error.

How to protect your website using simple PHP scripts

Denie — Fri, 20 Feb 2009 04:51:10 +0000

Just put below on your top line of the scripts :

$ips = array(”127.0.0.1″,”aaa.bbb.ccc”,”xxx.yyy.zzz”);
$userip = $_SERVER['REMOTE_ADDR'];
foreach ($ips as $ip) {
if (!preg_match(”/$ip/i”, $userip)) {
echo “Access Denied!”;
exit;
}
}

Notes:
$ips is the allowed IP address range

Other way, you can use .htaccess to protect directories/files.