Linux Security Cookbook [Electronic resources] نسخه متنی

Recipe 3.6 Adding a New Service (inetd)

3.6.1 Problem

You want to add a new network service, controlled by
inetd
.

3.6.2 Solution

Add a new line to /etc/inetd.conf
of the form:

SERVICE_NAME  SOCKET_TYPE  PROTOCOL  THREADING  USER  /PATH/TO/SERVER  ARGS

Then signal inetd to reread
/etc/inetd.conf. [Recipe 3.4]

3.6.3 Discussion

The values on the line are:

1. Service name . A service listed in
   /etc/services. If
   it's not, add an entry by selecting a service name,
   port number, and protocol. See services(5).




2. Socket type . Either
   stream, dgram,
   raw, rdm, or
   seqpacket.




3. Protocol . Typically tcp or
   udp.




4. Threading
   . Use
   wait for single-threaded, or
   nowait for multithreaded.




5. User . The service will run as this user.




6. Path to server executable.




7. Server arguments , separated by
   whitespace. You must begin with the zero^th
   argument, the server's basename itself. For example,
   for /usr/sbin/in.telnetd, the
   zero^th argument would be
   in.telnetd.

A full example is:

telnet  stream  tcp  nowait  root  /usr/sbin/in.telnetd  in.telnetd

A line in inetd.conf may contain a few other
details as well, specifying buffer sizes, a local host address for
listening, and so forth. See the manpage.

3.6.4 See Also

inetd(8), inetd.conf(5), services(5).