NAME

       qmail-popup - read a POP username and password

SYNOPSIS

       qmail-popup hostname subprogram

DESCRIPTION

       qmail-popup reads a POP username and password from the network.  It then runs subprogram.

       qmail-popup is most commonly invoked from inetd as

          qmail-popup CHANGEME checkpassword qmail-pop3d Maildir

       with CHANGEME replaced by the fully qualified domain name of the local host.

       qmail-popup  expects  descriptor 0 to read from the network and descriptor 1 to write to the network.  It
       reads a username and password from descriptor 0 in POP's USER-PASS  style  or  APOP  style.   It  invokes
       subprogram,  with  the  same  descriptors  0 and 1; descriptor 2 writing to the network; and descriptor 3
       reading the username, a 0 byte, the password, another 0 byte, an APOP timestamp  derived  from  hostname,
       and  a  final  0  byte.   qmail-popup then waits for subprogram to finish.  It prints an error message if
       subprogram crashes or exits nonzero.

       qmail-popup should be used only within a secure network.  Otherwise an eavesdropper can steal  passwords.
       Even if you use APOP, an active attacker can still take over the connection and wreak havoc.

       qmail-popup has a 20-minute idle timeout.

       qmail-popup is based on a program contributed by Russ Nelson.

SEE ALSO

       maildir(5), qmail-local(8), qmail-pop3d(8)

                                                                                                  qmail-popup(8)