Davrods - An Apache WebDAV interface to iRODS

Davrods provides access to iRODS servers using the WebDAV protocol. It is a bridge between the WebDAV protocol and the iRODS API, implemented as an Apache HTTPD module.

Davrods leverages the Apache server implementation of the WebDAV protocol, mod_dav, for compliance with the WebDAV Class 2 standard.

Notable features include:

• WebDAV Class 2 support, with locks local to the Apache server
• Connects to iRODS server versions 4+
• PAM and Native (a.k.a. STANDARD) iRODS authentication
• Optional negotiated SSL encryption for the entire iRODS connection
• Configurable using Apache configuration directives
• Optional anonymous access mode for password-less public access
• Themeable directory listings for read-only web browser access.
• Partial file up- and downloads and resumes (HTTP byte-ranges)
• iRODS ticket-based access

Themeable listings and anonymous access were inspired by Simon Tyrrell's work at Earlham Institute.

Download

Please choose the right version for your platform:

1. If you run Davrods on the same server as your iRODS service, you need a Davrods version built against the same version iRODS runtime.
2. If you run Davrods separately, on its own server, then the iRODS runtime version does not matter - just pick the newest Davrods you can get. All Davrods packages below should be compatible with any iRODS 4.x server version.

Date	Davrods ver.	iRODS runtime ver.	Packages	Remarks
2022-06-22	1.5.0	4.3.0	RPM, DEB	Pre-release
2023-07-27	1.5.1	4.2.12	RPM, DEB	Pre-release
2021-12-20	1.5.0	4.2.11	RPM, DEB
2021-07-28	1.5.0	4.2.10	RPM, DEB
2021-06-16	1.5.0	4.2.9	RPM, DEB
2020-06-02	1.5.0	4.2.8	RPM, DEB
2019-12-20	1.4.2	4.2.7	RPM, DEB
2019-06-20	1.4.2	4.2.6	RPM, DEB
2019-04-03	1.4.2	4.2.5	RPM, DEB
2018-12-17	1.4.2	4.2.4	RPM, DEB
2018-07-15	1.4.1	4.2.3	RPM, DEB
2018-07-15	1.4.1	4.1.x	RPM

(older versions are still available on the releases page)

If you require a certain Davrods/iRODS runtime version combination that is not listed above, you can most likely still build it yourself (see "Building from source").

A log describing which features were added and which bugs were fixed in each version can be found in changelog.txt.

We currently distribute RPM packages for CentOS 7 & RHEL systems and DEB packages for Debian & Ubuntu systems. We test our packages on CentOS 7 and (as of Davrods 1.4.0) Ubuntu 16.04.

Installation

This section describes the installation steps for iRODS 4.2+ based Davrods releases.

To view instructions for iRODS 4.1-based Davrods releases, switch to the irods-4.1-libs branch.

Using the binary distribution

Davrods depends on certain iRODS packages, which as of iRODS 4.2 are distributed at https://packages.irods.org/

After following the instructions for adding the iRODS repository to your package manager at the link above, Davrods can be installed as a binary package using the RPM or DEB file from the releases page (use the table near the top of this README to select the right version).

Download the Davrods package for your platform and install it using your package manager, for example:

yum install davrods-4.2.8_1.5.0-1.rpm
--or--
apt install davrods-4.2.8_1.5.0.deb

Now see the Configuration section for instructions on how to configure Davrods once it has been installed.

Davrods and SELinux

If the machine on which you install Davrods is protected by SELinux, you may need to make changes to your policies to allow Davrods to run:

• Apache HTTPD must be allowed to connect to TCP port 1247

For example, the following command can be used to resolve this requirement:

setsebool -P httpd_can_network_connect true

Configuration

Davrods is configured in two locations: In a HTTPD vhost configuration file and in an iRODS environment file. The vhost config is the main configuration file, the iRODS environment file is used for iRODS client library configuration, similar to the configuration of icommands.

HTTPD vhost configuration

The Davrods RPM distribution installs two vhost template files:

1. /etc/httpd/conf.d/davrods-vhost.conf
2. /etc/httpd/conf.d/davrods-anonymous-vhost.conf

(for Ubuntu, replace /etc/httpd/conf.d with /etc/apache2/sites-available)

These files are provided completely commented out. To enable either configuration, simply remove the first column of # signs, and then tune the settings to your needs.

Note that on Ubuntu, you will additionally need to enable the Davrods module and vhosts, like so:

a2enmod dav
a2enmod davrods
a2ensite davrods-vhost
a2ensite davrods-anonymous-vhost

The normal vhost configuration (1) provides sane defaults for authenticated access.

The anonymous vhost configuration (2) allows password-less public access using the anonymous iRODS account.

You can enable both configurations simultaneously, as long as their ServerName values are unique (for example, you might use dav.example.com for authenticated access and public.dav.example.com for anonymous access).

The iRODS environment file

The binary distribution installs the irods_environment.json file in /etc/httpd/irods. In most iRODS setups, this file can be used as is.

Importantly, options such as irods_host and irods_zone_name are not read from this file (and are omitted for that reason). These settings are taken from their equivalent Davrods configuration directives in the vhost config file instead.

Options in irods_environment.json that are known to affect Davrods behavior are the negotiation, ssl and encryption settings.

See the official documentation for more information on these settings: https://docs.irods.org/4.2.7/system_overview/configuration/#irodsirods_environmentjson

Ticket-based access

Ticket access is disabled by default, and requires special configuration to enable, depending on your use case. Please see README.advanced.md for more information.

Building from source

This repository includes a Vagrant configuration for building Davrods from source on either CentOS 7 (for the RPM package) or Ubuntu 18.04 LTS (for the DEB package). It can be found in vagrant/build. In order to build a package using Vagrant, edit the .env file in the Vagrant build directory. Adjust the BOXNAME and IRODS_VERSION vars as needed. Then run vagrant up to provision the VM. The VM has all dependencies pre-installed, as well as a clone of the Davrods repository. Log in on the VM using vagrant ssh, then generate the build directory and create the package (see below).

To build from source without using the Vagrant configuration, the following build-time dependencies must be installed (package names may differ on your platform):

• cmake
• make
• gcc
• httpd-devel >= 2.4
• irods-devel >= 4.2.0
• openssl-devel
• irods-runtime >= 4.2.0
• rpmdevtools (if you are creating an RPM)

Additionally, the following runtime dependencies must be installed:

• irods-runtime >= 4.2.0
• openssl-libs
• httpd >= 2.4

Follow these instructions to build from source:

• First, browse to the directory where you have unpacked the Davrods source distribution.

• Check whether your umask is set to a sane value. If the output of umask is not 0022, run umask 0022 to fix it. This is important for avoiding conflicts in created packages later on.

• Create and generate a build directory.

mkdir build
cd build
cmake ..

• Compile the project

make

Now you can either build an RPM/DEB or install the project without a package manager.

To create a package:

make package

That's it, you should now have an RPM or DEB in your build directory which you can install using yum or apt.

To install without a package manager on CentOS:

Run the following as user root:

make install
chown apache:apache /var/lib/davrods
chmod 700 /var/lib/davrods

To install without a package manager on Debian:

Run the following as user root:

make install
chown www-data:www-data /var/lib/davrods
chmod 700 /var/lib/davrods

To install without a package manager on other distros:

Linux distributions other than RHEL, Debian and their derivatives may have different HTTPD configuration and directory layouts, which are not currently supported by the build system. For this reason you will need to install the files manually on such Linux distributions:

• Copy mod_davrods.so to your Apache module directory.
• Copy davrods.conf to your Apache module configuration/load directory.
• Copy davrods-vhost.conf and davrods-anonymous-vhost.conf to your Apache vhost configuration directory.
• Create an irods directory in a location where Apache HTTPD has read access.
• Copy irods_environment.json to the irods directory.
• Create directory /var/lib/davrods, and give apache exclusive access to it.

Bugs and feature requests

Please report any issues you encounter on the issues page.

Contact information

For questions or support, please contact the Yoda team at [email protected].

Authors

• Chris Smeele

License

Copyright (c) 2016 - 2021, Utrecht University.

Davrods is licensed under the GNU Lesser General Public License version 3 or higher (LGPLv3+). See the COPYING.LESSER file for details.

The lock_local.c and byterange.c files were adapted from components of Apache HTTPD, and are used with permission granted by the Apache License. See the copyright and license notices in these files for details.