tinyleaf - Very simple IHAVE-only NNTP server
is intended to be the simplest possible transit news server that
still does something useful. It must be run under inetd
(8) or some
equivalent, and only implements three commands (HELP, IHAVE, and QUIT). When
it receives an article, it saves it into the directory spool
is given, passes information about the article to
via a pipe. The file name of the article will be the MD5 hash
of its message-ID, and if a file by that name already exists, tinyleaf
will refuse the article, reporting it as a duplicate.
is given, it should specify the path to a program. That
program is started when tinyleaf
starts, and its current working
directory will be spool
. For each article received by tinyleaf
a single line will be sent to standard input of processor
. That line
will consist of the file name of the received article (relative to
), a single space, and the message-ID of the received article.
Note that the message-ID will be taken from the argument to the IHAVE command
and may not match the Message-ID: header in the article. When tinyleaf
shuts down, standard input to processor
will be closed.
does no syntax verification of received articles whatsoever; it
just stores them and optionally passes them off to processor
. It also
never deletes articles; normally, processor
should do that when it's
finished doing whatever it needs to with the article.
expects NNTP commands on standard input and replies on standard
output. Status information and any error messages are sent to standard error.
It does no authentication; any authentication must be done by inetd
or by a wrapper program. (One simple authentication mechanism is to invoke
(8) from TCP wrappers and use
to restrict who can talk to
has a (currently hard-coded) maximum message size of 1 MB
and a (similarly hard-coded) timeout of ten minutes for each command or chunk
of article data.
Suppose that you want to archive news articles on a particular host (like the
FTP server for a newsgroup archive) where you don't want the overhead of
running a full-blown news server. Write a program that reads one line at a
time from standard input and treats everything before the first space as the
filename of a news article to archive. Each time the program reads a line, it
should archive that file and then delete it, and it should exit when it gets
end of file on standard input.
Then, add a line like:
nntp stream tcp nowait archive /usr/sbin/tcpd \
<pathbin>/tinyleaf <pathspool>/tinyleaf <pathbin>/archive
(all on one line -- the backslash and split in this line is just for
readability) where "archive" is the user that owns the archive,
is the path to tcpd
is the path to this program, pathspool
/tinyleaf is some scratch
directory that the user "archive" has write access to, and
/archive is the path to your archive
You can now restrict access to tinyleaf
to just your local news server
with "/etc/hosts.allow" and "/etc/hosts.deny" and set up
an ordinary feed from the server to the archive host, just like you would to
any other news server, of only the newsgroup that you want to archive.
Note that the archiving script should probably perform basic syntax and validity
checks on the input, since tinyleaf
This is the application that motivated the original development of this program.
The timeout and maximum message size should really be configurable.
should also probably not just respond 500 to every command
other than HELP, IHAVE, and QUIT; there are more useful (and more expected)
error codes that could be returned.
An option to scan the spool directory for any left-over files and pass them to
the processor when starting up would be useful.
Written by Russ Allbery <email@example.com> for InterNetNews.
$Id: tinyleaf.pod 9767 2014-12-07 21:13:43Z iulius $