Ubuntu Manpage: pure-authd - External authentication agent for Pure-FTPd.

Provided by: pure-ftpd-common_1.0.50-2.1ubuntu0.22.04.1_all

NAME

       pure-authd - External authentication agent for Pure-FTPd.

SYNTAX

       pure-authd  [-p  </path/to/pidfile>]  [-u  uid]  [-g  gid]  [-B]  <-s  /path/to/socket> -r
       /program/to/run

DESCRIPTION

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:

account:xxx

password:xxx

localhost:xxx

localport:xxx

peer:xxx

end

(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:

AUTHD_ACCOUNT

AUTHD_PASSWORD

AUTHD_LOCAL_IP

AUTHD_LOCAL_PORT

AUTHD_REMOTE_IP

AUTHD_ENCRYPTED

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:

auth_ok:1

uid:42

gid:21

dir:/home/j

end

auth_ok:xxx
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.

uid:xxx
The system uid to be assigned to that user. Must be > 0.

gid:xxx
The primary system gid. Must be > 0.

dir:xxx
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.

Only one authentication program is forked at a time. It must return quickly.

OPTIONS

       -u <uid>
              Have the daemon run with that uid.

       -g <gid>
              Have the daemon run with that gid.

       -B     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.

       -h     Output help information and exit.

EXAMPLES

       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:
              #! /bin/sh

              echo 'auth_ok:1'

              echo 'uid:42'

              echo 'gid:21'

              echo 'dir:/home/j'

              echo 'end'

AUTHORS