swd - The simple webdav server

swd is a simple webdav server that provides the following features:

• Single binary that runs under Windows, Linux and OSX.
• Authentication via HTTP-Basic.
• TLS support - if needed.
• A simple user management which allows user-directory-jails as well as full admin access to all subdirectories.
• Live config reload to allow editing of users without downtime.
• A cli tool to generate BCrypt password hashes.

It perfectly fits if you would like to give some people the possibility to upload, download or share files with common tools like the OSX Finder, Windows Explorer or Nautilus under Linux (or many other tools).

Table of Contents

• Configuration
  • First steps
  • TLS
  • Behind a proxy
  • User management
  • Logging
  • Live reload
• Installation
  • Binary-Installation
  • Build from sources
• Connecting
• Contributing
• License

Configuration

The configuration is done in form of a yaml file. swd will scan the following locations for the presence of a config.yaml in the following order:

• The directory ./config
• The directory $HOME/.swd
• The current working directory .

First steps

Here an example of a very simple but functional configuration:

address: "127.0.0.1"    # the bind address
port: "8000"            # the listening port
dir: "/home/webdav"     # the provided base dir
prefix: "/webdav"       # the url-prefix of the original url
users:
  user:                 # with password 'foo' and jailed access to '/home/webdav/user'
    password: "$2a$10$yITzSSNJZAdDZs8iVBQzkuZCzZ49PyjTiPIrmBUKUpB0pwX7eySvW"
    subdir: "/user"
  admin:                # with password 'foo' and access to '/home/webdav'
    password: "$2a$10$DaWhagZaxWnWAOXY0a55.eaYccgtMOL3lGlqI3spqIBGyM0MD.EN6"

With this configuration you'll grant access for two users and the webdav server is available under http://127.0.0.1:8000/webdav.

TLS

At first, use your favorite toolchain to obtain a SSL certificate and keyfile (if you don't already have some).

Here an example with openssl:

# Generate a keypair
openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365
# Remove the passphrase from the key file
openssl rsa -in key.pem -out clean_key.pem

Now you can reference your keypair in the configuration via:

address: "127.0.0.1"    # the bind address
port: "8000"            # the listening port
dir: "/home/webdav"     # the provided base directory
tls:
  keyFile: clean_key.pem
  certFile: cert.pem
users:
...

The presence of the tls section is completely enough to let the server start with a TLS secured https connection.

In the current release version you must take care, that the private key doesn't need a passphrase. Otherwise starting the server will fail.

Behind a proxy

swd will also work behind a reverse proxy. Here is an example configuration with apache2 httpd's mod_proxy:

<Location /webdav>
  ProxyPass           https://webdav-host:8000/
  ProxyPassReverse    https://webdav-host:8000/
</Location>

User management

User management in swd is very simple. Each user in the config.yaml MUST have a password and CAN have a subdirectory.

The password must be in form of a BCrypt hash. You can generate one calling the shipped cli tool swdcli passwd.

If a subdirectory is configured for a user, the user is jailed within it and can't see anything that exists outside of this directory. If no subdirectory is configured for an user, the user can see and modify all files within the base directory.

Logging

You can enable / disable logging for the following operations:

• Creation of files or directories
• Reading of files or directories
• Updating of files or directories
• Deletion of files or directories

You can also enable or disable the error log.

All file-operation logs are disabled per default until you will turn it on via the following config entries:

address: "127.0.0.1"    # the bind address
port: "8000"            # the listening port
dir: "/home/webdav"     # the provided base directory
log:
  error: true
  create: true
  read: true
  update: true
  delete: true
...

Be aware, that the log pattern of an attached tty differs from the log pattern of a detached tty.

Example of an attached tty:

INFO[0000] Server is starting and listening              address=0.0.0.0 port=8000 security=none

Example of a detached tty:

time="2018-04-14T20:46:00+02:00" level=info msg="Server is starting and listening" address=0.0.0.0 port=8000 security=none

Live reload

There is no need to restart the server itself, if you're editing the user or log section of the configuration. The config file will be re-read and the application will update it's own configuration silently in background.

Installation

Binary installation

You can check out the releases page for the latest precompiled binaries.

Build from sources

At first you have to clone the repository with:

git clone git@github.com:micromata/swd.git

To build and install from sources you have two major possibilites:

go install

You can use the plain go toolchain and install the project to your $GOPATH via: go install ./....

magefile

You can also use mage to build the project.

Please ensure you've got mage installed. This can be done with the following steps:

go get -u -d github.com/magefile/mage
cd $GOPATH/src/github.com/magefile/mage
go run bootstrap.go

Now you can call mage install to build and install the binaries. If you just call mage, you'll get a list of possible targets:

Targets:
  build            Builds swd and swdcli and moves it to the dist directory
  buildReleases    Builds swd and swdcli for different OS and package them to a zip file for each os
  check            Runs golint and go tool vet on each .go file.
  clean            Removes the dist directory
  fmt              Formats the code via gofmt
  install          Installs swd and swdcli to your $GOPATH/bin folder
  installDeps      Runs dep ensure and installs additional dependencies.

Connecting

You could simply connect to the webdav server with a http(s) connection and a tool that allows the webdav protocol.

For example: Under OSX you can use the default file management tool Finder. Press CMD+K, enter the server address (e.g. http://localhost:8000) and choose connect.

Contributing

Everyone is welcome to create pull requests for this project. If you're new to github, take a look here to get an idea of it.

If you'd like to contribute, please make sure to use the magefile and execute and check the following commands before starting a PR:

mage fmt
mage check

If you've got an idea of a function that should find it's way into this project, but you won't implement it by yourself, please create a new issue.

License

Please be aware of the licenses of the components we use in this project. Everything else that has been developed by the contributions to this project is under Apache 2 License.