pure-authd (8) - Linux Man Pages
pure-authd: External authentication agent for Pure-FTPd.
pure-authd [-p </path/to/pidfile>] [-u uid] [-g gid] [-B] <-s /path/to/socket> -r /program/to/run
pure-authd is a daemon that forks an authentication program, waits for an authentication reply, and feed them to an application server.
pure-authd listens to a local Unix socket. A new connection to that socket should feed pure-authd the following structure :
(replace xxx with appropriate values) . localhost, localport and peer are numeric IP addresses and ports. peer is the IP address of the remote client.
These arguments are passed to the authentication program, as environment variables :
The authentication program should take appropriate actions to fetch account info according to these arguments, and reply to the standard output a structure like the following one :
- If xxx is 0, the user was not found (the next authentication method passed to pure-ftpd will be tried) . If xxx is -1, the user was found, but there was a fatal authentication error : user is root, password is wrong, account has expired, etc (next authentication methods will not be tried) . If xxx is 1, the user was found and successfully authenticated.
- The system uid to be assigned to that user. Must be > 0.
- The primary system gid. Must be > 0.
- The absolute path to the home directory. Can contain /./ for a chroot jail.
- slow_tilde_expansion:xxx (optional, default is 1)
- When the command 'cd ~user' is issued, it's handy to go to that user's home directory, as expected in a shell environment. But fetching account info can be an expensive operation for non-system accounts. If xxx is 0, 'cd ~user' will expand to the system user home directory. If xxx is 1, 'cd ~user' won't expand. You should use 1 in most cases with external authentication, when your FTP users don't match system users. You can also set xxx to 1 if you're using slow nss_* system authentication modules.
- throttling_bandwidth_ul:xxx (optional)
- The allocated bandwidth for uploads, in bytes per second.
- throttling_bandwidth_dl:xxx (optional)
- The allocated bandwidth for downloads, in bytes per second.
- user_quota_size:xxx (optional)
- The maximal total size for this account, in bytes.
- user_quota_files:xxx (optional)
- The maximal number of files for this account.
- ratio_upload:xxx (optional)
- radio_download:xxx (optional)
- The user must match a ratio_upload:ratio_download ratio.
- -u <uid>
- Have the daemon run with that uid.
- -g <gid>
- Have the daemon run with that gid.
- Fork in background (daemonization).
- -s </path/to/socket>
- Set the full path to the local Unix socket.
- -R </path/to/program>
- Set the full path to the authentication program.
- Output help information and exit.
To run this program the standard way type:
pure-authd -s /var/run/ftpd.sock -r /usr/bin/my-auth-program &
pure-ftpd -lextauth:/var/run/ftpd.sock &
- /usr/bin/my-auth-program can be as simple as :