ProFTPD - Customized FTP server instance
Originally by mindbender.
It is presently being reworked by shryke.
Linkstation 2 (MIPSEL)
Stock Proftpd v1.2.9
The Linkstation comes with two different FTP Server deamons.
There is a script file to start wu-ftpd or proftpd (depending on whether you choose anonymous or user-based FTP). This file resides here: /etc/init.d/ftpd and gets called during boot via symlink S92ftpd in rc2.d
If you want to make your configuration changes permanent, you need to keep the linkstation from rewriting the file /etc/proftpd.conf
To achieve this, the file /etc/init.d/mkshare.sh needs to be edited. Only the 5 lines below
# echo "FTP configration file generating..."
need to be commented out.
#generate configuration files if [ -x /bin/mkcode ]; then echo "Netatalk configration file generating..." /bin/mkcode -a > /dev/null /bin/nkf -sEO /etc/atalk/AppleVolumes.default /tmp/AppleVolumes mv -f /tmp/AppleVolumes /etc/atalk/AppleVolumes.default echo "Samba configration file generating..." /bin/mkcode -s > /dev/null /bin/nkf -sEO /etc/samba/smb.conf /tmp/smb.conf mv -f /tmp/smb.conf /etc/samba/smb.conf # echo "FTP configration file generating..." # /bin/mkcode -f > /dev/null # /bin/nkf -sEO /etc/wu-ftpd/ftpaccess /tmp/ftpaccess # mv -f /tmp/ftpaccess /etc/wu-ftpd/ftpaccess # /bin/nkf -sEO /etc/proftpd.conf /tmp/proftpd.conf # mv -f /tmp/proftpd.conf /etc/proftpd.conf fi
Now you can edit /etc/proftpd.conf and it will actually stay that way.
If you speak german, here is a good spot to start your research on how to customize your PROFTPD configuration.
I will add some examples and explanations shortly.
As documentation I looked into http://www.proftpd.org/docs/ mainly to look what I needed for the config file (I wanted to assign different priviledges to virtual users).
The rest is really up to what you want to do with the new server, proftpd is very flexible. I really enjoyed the granularity on access priviledges on a user basis and the possibility to create "virtual users" (ftp users without the need of a full account on the linkstation).
Authentication with "virtual users" (non-system users)
I added these to my config file
AuthPAMAuthoritative off AuthPAMConfig ftp AuthGroupFile /etc/ftp2ndgroup AuthUserFile /etc/ftp2ndpasswd
What happens then is that, if the user has an "regular account" on the linkstation (i.e. the user is in the usual /etc/passwd file and the group is in the /etc/group file) then he/she can login with the linkstation login password.
So you dont have to duplicate your own user account. If the user is not in /etc/passwd then the file /etc/ftp2ndpasswd is looked. The format is exactly the same as /etc/passwd but you have to use fake id number that wont overlap with the ones in the normal passwd file.
To generate password hashes needed in /etc/passwd, you can use the "htpasswd -n username" command. In some cases it might be needed for the home directory and the shell indicated in /etc/ftp2ndpasswd do actually point to existing directories and shell.