Copyright © 2002, 2003 Peter Jones (http://pmade.org/pjones/)
This is the manual for the mod_injection Apache module.
The latest version of this manual can be found at http://pmade.org/pjones/software/mod_injection/.
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mod_injection is an Apache 2.0.X filter module. It allows you to inject text in the HTTP response after a HTML tag or after any given text string. The main intention of this module is to add a banner to several HTML pages on the fly.
mod_injection has the following features.
Injection can happen after any HTML tag (default is the BODY tag).
Injection can also happen after a specific text string has been seen in the output.
Injection of a string from the Apache configuration file.
Injection of an entire URI.
Injection is based on the Content-Type. You can specify which MIME types you want to inject for.
This section will show you how to install mod_injection using the supplied Makefiles.
Make sure that apxs is either in your path or make sure that you give it to make like this: make APXS=/path/to/apxs
From the top directory, run make. This must be GNU make and on some systems it is called gmake.
After everything is done compiling you can run make install.
Update your Apache configuration file.
The first thing that you need to do is load mod_injection. If your module directory is called modules you can load mod_injection with the following Apache configuration directive:
LoadModule injection_module modules/mod_injection.so
Like other filter modules, there are many different ways to enable mod_injection. If you wanted to link mod_injection to a file extension you could do the following.
AddOutputFilter INJECTION .html
Most likely you are going to want to filter all files under a given directory regardless of their file extension. Here is an example of an Apache directory directive that uses mod_injection.
<Directory />
SetOutputFilter INJECTION
InjectString "<h1>Injected</h1>"
</Directory>
By default, mod_injection only filters content that has a MIME
type of text/html. You can override this
using the InjectType configuration
directive.
This directive can be repeated as many times as you wish. It can
also contain shell style glob patterns. Here is an example that
tells mod_injection to filter any content that has a MIME type
that begins with text/.
InjectType text/*
This final section on configuration will explain all the directives that mod_injection can use.
InjectTag - Set the tag to inject after.
Example: InjectTag title
InjectAfter - Set a string to find and inject after.
Example: InjectAfter "!-- here --"
InjectString - Set a string to inject at the injection point.
Example: InjectString "h1Injected!h1"
InjectURI - Set the name of a URI that should be injected at the injection point.
Example: InjectURI /injectme.html
InjectType - Add a MIME type to filter.
If you don't use this, the default type is text/html.
This option can also have shell style glob patterns like text/*.
Note: You cannot use
InjectStringandInjectURIin the same location. Only use one at a time.
Note: You cannot use
InjectTagandInjectAfterin the same location. Only use one at a time.
mod_injection should compile anywhere that Apache does. You need the following software tools to build mod_injection.
Required Software
The Apache web server, at least version 2.0.40.
The same C compiler you used to compile Apache.
GNU Make (since the Apache build Makefiles use GNU specific code).
The apxs program that comes with Apache.
Fixed a bug where mod_injection would try to run on a response that contained no body. This would cause a core dump because mod_injection would try to inspect a NULL content type header.
Added InjectTag to set the name of the tag to inject after. Default is still BODY.
Added InjectAfter so you can set a string to inject after.
Updated for Apache filter API change. This change requires you to be using at least version 2.0.40 of the Apache web server.
Removed the InjectFile directive for security reasons. You can use the InjectURI directive to get the same results.
Added some safety checks to make sure the configuration is sane.
Optimized the code, mod_injection works much faster now.
mod_injection was written by Peter Jones.
I also would like to say thank you to Sebastian Wolfgarten for including mod_injection in his book "Apache Webserver 2.0".