* SSL based server (sslxmlrpc_server.py) that wraps the existing Python
  classes (what we export via the existing ssh XMLRPC server). I also have a
  demo client that is analogous the ssh demo client (sslxmlrpc_client.py).
  This client looks for an ssl cert in the user's .ssl directory, or you can
  specify one on the command line. The demo client is installed on ops, and
  is in the downloads directory with the rest of the xmlrpc stuff we export
  to users. The server runs as root, forking a child for each connection and
  logs connections to /usr/testbed/log/sslxmlrpc.log via syslog.

* New script (mkusercert) generates SSL certs for users. Two modes of
  operation; when called from the account creation path, generates a
  unencrypted private key and certificate for use on Emulab nodes (this is
  analagous to the unencrypted SSH key we generate for users). The other mode
  of operation is used to generate an encrypted private key so that the user
  can drag a certificate to their home/desktop machine.

* New webpage (gensslcert.php3) linked in from the My Emulab page that
  allows users to create a certificate. The user is prompted for a pass
  phrase to encrypt the private key, as well as the user's current Emulab
  login password. mkusercert is called to generate the certificate, and the
  result is stored in the user's ~/.ssl directory, and spit back to the user
  as a text file that can be downloaded and placed in the users homedir on
  their local machine.

* The server needs to associate a certificate with a user so that it can
  flip to that user in the child after it forks. To do that, I have stored
  the uid of the user in the certificate. When a connection comes in, I grab
  the uid out of the certificate and check it against the DB. If there is a
  match (see below) the child does the usual setgid,setgroups,setuid to the
  user, instantiates the Emulab server class, and dispatches the method. At
  the moment, only one request per connection is dispatched. I'm not sure
  how to do a persistant connection on the SSL path, but probably not a big
  deal right now.

* New DB table user_sslcerts that stores the PEM formatted certificates and
  private keys, as well as the serial number of the certificate, for each
  user. I also mark if the private key is encrypted or not, although not
  making any use of this data. At the moment, each user is allowed to get
  one unencrypted cert/key pair and one encrypted cert/key pair. No real
  reason except that I do not want to spend too much time on this until we
  see how/if it gets used. Anyway, the serial number is used as a crude form
  of certificate revocation. When the connection is made, I suck the serial
  number and uid out of the certificate, and look for a match in the table.
  If cert serial number does not match, the connection is rejected. In other
  words, revoking a certificate just means removing its entry from the DB
  for that user. I could also compare the certificate itself, but I am not
  sure what purpose that would serve since that is what the SSL handshake is
  supposed to take of, right?

* Updated the documentation for the XMLRPC server to mention the existence
  of the SSL server and client, with a pointer into the downloads directory
  where users can pick up the client.