Cloud Servers Authentication¶
When a user interacts with Sunstone, the server authenticates the request and then forwards the requested operation to the OpenNebula daemon.
The forwarded requests between the server and the core daemon include the original user name, and are signed with the credentials of a special
In this guide this request forwarding mechanism is explained, and how it is secured with a symmetric-key algorithm or x509 certificates.
The Sunstone server communicate with the core using a
server user. OpenNebula creates the serveradmin account at bootstrap, with the authentication driver server_cipher (symmetric key).
server user uses a special authentication mechanism that allows the servers to perform an operation on behalf of another user.
You can strengthen the security of the requests from the servers to the core daemon by changing the serveruser’s driver to server_x509. This is specially relevant if you are running your server in a machine other than the frontend.
Please note that you can have as many users with a server_* driver as you need. For example, you may want to have Sunstone configured with a user with server_x509 driver, and EC2 with server_cipher.
This mechanism is enabled by default, you will have a user named serveradmin with driver server_cipher.
To use it, you need a user with the driver server_cipher. Enable it in the relevant configuration file in
You must update the configuration files in
/var/lib/one/.one if you change the serveradmin’s password, or create a different user with the server_cipher driver.
ls -1 /var/lib/one/.one ec2_auth sunstone_auth cat /var/lib/one/.one/sunstone_auth serveradmin:1612b78a4843647a4b541346f678f9e1b43bbcf9
serveradmin password is hashed in the database. You can use the
--sha256 flag when issuing
oneuser passwd command for this user.
When Sunstone is running in a different machine than oned you should use an SSL connection. This can be archived with an SSL proxy like stunnel or apache/nginx acting as proxy. After securing the OpenNebula XML-RPC connection, configure Sunstone to use https with the proxy port:
To enable it, change the authentication driver of the serveradmin user, or create a new user with the driver server_x509:
oneuser chauth serveradmin server_x509 oneuser passwd serveradmin --x509 --cert usercert.pem
The serveradmin account should look like:
oneuser list ID GROUP NAME AUTH PASSWORD 0 oneadmin oneadmin core c24783ba96a35464632a624d9f829136edc0175e 1 oneadmin serveradmin server_x /C=ES/O=ONE/OU=DEV/CN=server
You need to edit
/etc/one/auth/server_x509_auth.conf and uncomment all the fields. The defaults should work:
# User to be used for x509 server authentication :srv_user: serveradmin # Path to the certificate used by the OpenNebula Services # Certificates must be in PEM format :one_cert: "/etc/one/auth/cert.pem" :one_key: "/etc/one/auth/pk.pem"
Copy the certificate and the private key to the paths set in
:one_key:, or simply update the paths.
Then edit the relevant configuration file in
To trust the serveradmin certificate (
/etc/one/auth/cert.pem if you used the default path) the CA’s certificate must be added to the
ca_dir defined in
/etc/one/auth/x509_auth.conf. See the x509 Authentication guide for more information.
openssl x509 -noout -hash -in cacert.pem 78d0bbd8 sudo cp cacert.pem /etc/one/auth/certificates/78d0bbd8.0
Tuning & Extending¶
You can find the drivers in these paths:
Authentication Session String¶
OpenNebula users with the driver server_cipher or server_x509 use a special authentication session string (the first parameter of the XML-RPC calls). A regular authentication token is in the form:
whereas a user with a server_* driver must use this token format:
The core daemon understands a request with this authentication session token as “perform this operation on behalf of target_user”. The
secret part of the token is signed with one of the two mechanisms explained before.