HTTPS SSH

Apache HTTPd Stream Security Plugin

This plugin brings Opencast Stream Security to the Apache HTTPd server. More information about Opencast Stream Security can be found in the Opencast Administration Guide.

Opencast installations can use Apache HTTPd to distribute files over HTTP or HTTPS, with the verification of signed URLs carried out by a custom component available from Bitbucket: http://bitbucket.org/opencast-community/apache-httpd-stream-security-plugin.

Install Dependencies

In order to build the HTTPd component, some dependencies need to be installed first. The example routine is based on CentOS 6 and will work similarly using alternate platforms and/or package managers.

1. Install Package Dependencies For Your Platform (Example is CentOS 6)

sudo yum install httpd-devel libtool openssl-devel

2. Install Jansson For Json Support

cd /tmp
wget http://www.digip.org/jansson/releases/jansson-2.10.tar.gz
tar -xvf jansson-2.10.tar.gz
cd jansson-2.10
./configure
make
make check
sudo make install
sudo ln -s /usr/local/lib/libjansson.so.4 /usr/lib/libjansson.so.4
sudo ldconfig

Install Stream Security HTTPd Component

Once the dependencies are in place, the HTTPd component can be built with the following commands:

sudo yum install git
cd /tmp
git clone http://bitbucket.org/opencast-community/apache-httpd-stream-security-plugin.git
cd apache-httpd-stream-security-plugin
./configure
make
sudo make install

Configure

In order to use stream security load the module in the httpd config with

LoadModule stream_security_module modules/mod_stream_security.so

The Stream Security component is implemented as an Apache Handler. To activate the component, the handler must be added to the HTTPd configuration:

<Directory "/var/matterhorn/distribution/downloads">
    ...
    SetHandler stream-security
    ...
</Directory>

Besides the handler, there are two directives which need to be defined: StreamSecurityEnabled - (On/Off, default On) StreamSecurityKeysPath - {path to the keys file}

Example:

<VirtualHost *:80>    
    ...
    StreamSecurityEnabled On
    StreamSecurityKeysPath /etc/httpd/conf/stream-security-keys.json
    ...
</VirtualHost>

Additionally, there are two optional directives which can be defined: StreamSecurityDebug - (On/Off, default Off) - Returns an html document of the result of the request for a resource instead of actually returning the resource / denying the source. Useful for trying to determine why a request for a resource failed. StreamSecurityStrict - (On/Off, default On) - If turned on, the entire URL will be considered when comparing the current request for a resource against the policy, including the scheme (http, https etc.), hostname and optional port. If turned off, only the path to the resource will be considered. So if the request is for a resource at http://download.matterhorn.com:8080/the/full/path/video.mp4, and strict mode is disabled, only the /the/full/path/video.mp4 will be checked against the policy. This flexibility is useful when using things like load balancers, where the Apache hostname may not match the requested hostname or if a video player is rewriting requests, e.g. by inserting the port number.

Keys File

The final configuration involves setting the parameters for id and key for each key. The entries here need to have the same values for id and key as used for the Signing Providers configuration, because the id is part of the policy and the key is used to sign and verify the request.

An example configuration file is contained in the component code called stream-security-keys.json and as below:

Example:

{
  "keys":[
    {
      "id":"demoKeyOne",
      "key":"6EDB5EDDCF994B7432C371D7C274F"
    },
    {
      "id":"demoKeyTwo",
      "key":"C843C21ECF59F2B38872A1BCAA774"
    }
  ]
}

Development

Bump version of plugin

Bumping the version of the plugin is a manual task and involves two steps:

  1. Change the version in the file configure.ac in the AC_INIT section.
  2. Rebuild the configure file by running the autoconf tool without any further parameters.

Changes in both files, configure.ac and configure need to be committed to the version control system.

Docker based build environment

The project comes with a Dockerfile which defines a Docker image useful for tasks during development. In order to build the image, execute this task:

docker build -t stream-security-build-env .

Build distribution archive

The distribution archive can be created leveraging the Docker image created in the previous step by executing this command:

docker run --rm -v $(pwd):/tmp -w /tmp stream-security-build-env ./configure && make dist distclean

As a result, you should find the archive in your working directory.