+-----------------------------------------------------------------------
| Customizing ${PKGSTEM} execution on OpenBSD
+-----------------------------------------------------------------------

Caution regarding built-in Webserver
====================================

The Hercules program allows for configuration to enable a webserver
with included CGI binaries to display System/370 registers and status.

It connects to all IPv4 interfaces and is generally accessible
without a password.

You should carefully consider your PF configuration to limit
access to this webserver.

Additionally, most System/370 operating systems support 3270-style
terminals.  (The x3270 package is useful here.)  The virtual
machines open port 3270 and connect to all IPv4 addresses.

Sample pf.conf entries

    # Do not permit remote connections to Hercules VMs
    block return in on ! lo0 proto tcp to port 3270
    block return in on ! lo0 proto tcp to port 8081

Sources for System/370 operating systems
========================================

For downloadable public-domain System/370 operating systems see

    https://www.ibiblio.org/jmaynard/

and

    https://try-mts.com/

At least MTS and VM/370 are known to work.
