pure-authd(8)

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

Frank DENIS <j at pureftpd dot org>

SEE ALSO
ftp(1), pure-ftpd(8) pure-ftpwho(8) pure-mrtginfo(8) pure-uploadscript(8) pure-statsdecode(8) pure-pw(8) pure-quotacheck(8) pure-authd(8) pure-certd(8)

RFC 959, RFC 2389, RFC 2228 and RFC 2428.