automatic user generation for ftp-upload service

[Franz Waldmüller]

I kindly ask for some advice for a rather challenging (at least for me) 
task:
The guests of a wedding should be able to upload their photos to a 
server. The task is to collect the pictures, not to make a gallery.

I want to avoid online photo-services: we don't want any restrictions on 
image size, total size and want to ensure that the data is only accessed 
by certain people.
This is the solution (?) I figured out and would like to realize:
Use the vsftpd ftp-server but disable anonymous write access. Instead 
automatically create 150 users with random passwords. This users should 
only access the ftp server but since the cannot access it physically I 
will only have to disable their ability to login with ssh (I will use to 
the openssh-server package for remote administration).

Task 1: create the user list random name and random password and export 
the user list to a text file.
(I will use glabels print individual login cards for each guest.)

Task 2: configure vsftpd:
Each user should be able to create directories and to copy files to the 
server.
Restricting every user to its home directory should be sufficient.

Task 3: Demand my administrator to open the required ports. I am not yet 
sure about which ports to demand.
port 22 for the remote ssh access but for ftp I will have to specify 
several ports (passive range). I will figure out which ones are needed.

With this solution I hope that everybody will be able to transfer files 
from his (Windows-) PC to the server just using the Windows-Explorer 
File Manager. The login-cards which will be handed out to the guest will 
feature a small “how to upload” but still is has to remain very easy.

Do you know if the Windows Explorer will handle this? Is there something 
to take about or do you have some advice for a better solution?
I am confident that I will be able to manage the vsftpd config, but I 
would appreciate some help on the generation of the user list.

Thank you very much

Franz