907 lines
22 KiB
Groff
907 lines
22 KiB
Groff
.\" Copyright (c) 1985, 1991, 1993, 1994
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" from: @(#)inetd.8 8.3 (Berkeley) 4/13/94
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.\" $FreeBSD$
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.\"
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.Dd February 7, 1996
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.Dt INETD 8
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.Os BSD 4.4
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.Sh NAME
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.Nm inetd
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.Nd internet
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.Dq super-server
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.Sh SYNOPSIS
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.Nm
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.Op Fl d
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.Op Fl l
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.Op Fl w
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.Op Fl W
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.Op Fl c Ar maximum
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.Op Fl C Ar rate
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.Op Fl a Ar address | hostname
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.Op Fl p Ar filename
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.Op Fl R Ar rate
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.Op Ar configuration file
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.Sh DESCRIPTION
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The
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.Nm
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program
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should be run at boot time by
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.Pa /etc/rc
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(see
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.Xr rc 8 ) .
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It then listens for connections on certain
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internet sockets. When a connection is found on one
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of its sockets, it decides what service the socket
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corresponds to, and invokes a program to service the request.
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The server program is invoked with the service socket
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as its standard input, output and error descriptors.
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After the program is
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finished,
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.Nm
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continues to listen on the socket (except in some cases which
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will be described below). Essentially,
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.Nm
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allows running one daemon to invoke several others,
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reducing load on the system.
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.Pp
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The following options are available:
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.Bl -tag -width indent
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.It Fl d
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Turn on debugging.
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.It Fl l
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Turn on logging of successful connections.
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.It Fl w
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Turn on TCP Wrapping for external services.
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See the
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.Sx "IMPLEMENTATION NOTES"
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section for more information on TCP Wrappers support.
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.It Fl W
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Turn on TCP Wrapping for internal services which are built in to
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.Nm .
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.It Fl c Ar maximum
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Specify the default maximum number of
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simultaneous invocations of each service;
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the default is unlimited.
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May be overridden on a per-service basis with the "max-child"
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parameter.
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.It Fl C Ar rate
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Specify the default maximum number of times a service can be invoked
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from a single IP address in one minute; the default is unlimited.
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May be overridden on a per-service basis with the
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"max-connections-per-ip-per-minute" parameter.
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.It Fl R Ar rate
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Specify the maximum number of times a service can be invoked
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in one minute; the default is 256.
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A rate of 0 allows an unlimited number of invocations.
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.It Fl a
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Specify one specific IP address to bind to.
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Alternatively, a hostname can be specified,
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in which case the IPv4 or IPv6 address
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which corresponds to that hostname is used.
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Usually a hostname is specified when
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.Nm
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is run inside a
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.Xr jail 8 ,
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in which case the hostname corresponds to the
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.Xr jail 8
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environment.
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.Pp
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When hostname specification is used
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and both IPv4 and IPv6 bindings are desired,
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one entry with the appropriate
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.Em protocol
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type for each binding
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is required for each service in
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.Pa /etc/inetd.conf .
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For example,
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a TCP-based service would need two entries,
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one using
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.Dq tcp4
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for the
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.Em protocol
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and the other using
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.Dq tcp6 .
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See the explanation of the
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.Pa /etc/inetd.conf
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.Em protocol
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field below.
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.It Fl p
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Specify an alternate file in which to store the process ID.
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.El
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.Pp
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Upon execution,
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.Nm
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reads its configuration information from a configuration
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file which, by default, is
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.Pa /etc/inetd.conf .
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There must be an entry for each field of the configuration
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file, with entries for each field separated by a tab or
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a space. Comments are denoted by a
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.Dq #
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at the beginning
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of a line. There must be an entry for each field. The
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fields of the configuration file are as follows:
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.Pp
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.Bd -unfilled -offset indent -compact
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service name
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socket type
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protocol
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{wait|nowait}[/max-child[/max-connections-per-ip-per-minute]]
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user[:group][/login-class]
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server program
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server program arguments
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.Ed
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.Pp
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To specify an
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.Tn "ONC RPC" Ns -based
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service, the entry would contain these fields:
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.Pp
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.Bd -unfilled -offset indent -compact
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service name/version
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socket type
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rpc/protocol
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user[:group][/login-class]
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server program
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server program arguments
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.Ed
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.Pp
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There are two types of services that
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.Nm
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can start: standard and TCPMUX.
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A standard service has a well-known port assigned to it;
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it may be a service that implements an official Internet standard or is a
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BSD-specific service.
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As described in
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.Tn RFC 1078 ,
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TCPMUX services are nonstandard services that do not have a
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well-known port assigned to them.
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They are invoked from
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.Nm
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when a program connects to the
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.Dq tcpmux
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well-known port and specifies
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the service name.
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This feature is useful for adding locally-developed servers.
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TCPMUX requests are only accepted when the multiplexor service itself
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is enabled, above and beyond and specific TCPMUX-based servers; see the
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discussion of internal services below.
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.Pp
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The
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.Em service-name
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entry is the name of a valid service in
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the file
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.Pa /etc/services ,
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or the specification of a
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.Ux
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domain socket (see below).
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For
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.Dq internal
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services (discussed below), the service
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name
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should
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be the official name of the service (that is, the first entry in
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.Pa /etc/services ) .
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When used to specify an
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.Tn "ONC RPC" Ns -based
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service, this field is a valid RPC service name in
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the file
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.Pa /etc/rpc .
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The part on the right of the
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.Dq /
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is the RPC version number.
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This
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can simply be a single numeric argument or a range of versions.
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A range is bounded by the low version to the high version -
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.Dq rusers/1-3 .
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For TCPMUX services, the value of the
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.Em service-name
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field consists of the string
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.Dq tcpmux
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followed by a slash and the
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locally-chosen service name.
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The service names listed in
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.Pa /etc/services
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and the name
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.Dq help
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are reserved.
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Try to choose unique names for your TCPMUX services by prefixing them with
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your organization's name and suffixing them with a version number.
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.Pp
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The
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.Em socket-type
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should be one of
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.Dq stream ,
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.Dq dgram ,
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.Dq raw ,
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.Dq rdm ,
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or
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.Dq seqpacket ,
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depending on whether the socket is a stream, datagram, raw,
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reliably delivered message, or sequenced packet socket.
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TCPMUX services must use
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.Dq stream .
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.Pp
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The
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.Em protocol
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must be a valid protocol or
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.Dq unix .
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Examples are
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.Dq tcp
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or
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.Dq udp ,
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both of which imply IPv4 for backward compatibility.
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The names
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.Dq tcp4
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and
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.Dq udp4
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specify IPv4 only.
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The names
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.Dq tcp6
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and
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.Dq udp6
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specify IPv6 only.
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The names
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.Dq tcp46
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and
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.Dq udp46
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specify that the entry accepts both IPv6 and IPv6 connections
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via a wildcard
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.Dv AF_INET6
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socket.
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If it is desired that the service is reachable via T/TCP, one should
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specify
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.Dq tcp/ttcp ,
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which implies IPv4 for backward compatibility.
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The name
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.Dq tcp4/ttcp
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specifies IPv4 only, while
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.Dq tcp6/ttcp
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specifies IPv6 only.
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The name
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.Dq tcp46/ttcp
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specify that the entry accepts both IPv6 and IPv6 connections
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via a wildcard
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.Dv AF_INET6
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socket.
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Rpc based services
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(for which only IPv4 is supported at this time)
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are specified with the
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.Dq rpc/tcp
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or
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.Dq rpc/udp
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service type.
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TCPMUX services must use
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.Dq tcp ,
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.Dq tcp4 ,
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.Dq tcp6
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or
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.Dq tcp46 .
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.Pp
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The
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.Em wait/nowait
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entry specifies whether the server that is invoked by
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.Nm
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will take over
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the socket associated with the service access point, and thus whether
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.Nm
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should wait for the server to exit before listening for new service
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requests.
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Datagram servers must use
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.Dq wait ,
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as they are always invoked with the original datagram socket bound
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to the specified service address.
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These servers must read at least one datagram from the socket
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before exiting.
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If a datagram server connects
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to its peer, freeing the socket so
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.Nm
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can receive further messages on the socket, it is said to be
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a
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.Dq multi-threaded
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server;
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it should read one datagram from the socket and create a new socket
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connected to the peer.
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It should fork, and the parent should then exit
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to allow
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.Nm
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to check for new service requests to spawn new servers.
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Datagram servers which process all incoming datagrams
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on a socket and eventually time out are said to be
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.Dq single-threaded .
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.Xr Comsat 8 ,
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.Pq Xr biff 1
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and
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.Xr talkd 8
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are both examples of the latter type of
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datagram server.
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.Xr Tftpd 8
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is an example of a multi-threaded datagram server.
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.Pp
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Servers using stream sockets generally are multi-threaded and
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use the
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.Dq nowait
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entry.
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Connection requests for these services are accepted by
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.Nm ,
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and the server is given only the newly-accepted socket connected
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to a client of the service.
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Most stream-based services operate in this manner.
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Stream-based servers that use
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.Dq wait
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are started with the listening service socket, and must accept
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at least one connection request before exiting.
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Such a server would normally accept and process incoming connection
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requests until a timeout.
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TCPMUX services must use
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.Dq nowait .
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.Pp
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The maximum number of outstanding child processes (or
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.Dq threads )
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for a
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.Dq nowait
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service may be explicitly specified by appending a
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.Dq /
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followed by the number to the
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.Dq nowait
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keyword.
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Normally
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(or if a value of zero is specified) there is no maximum.
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Otherwise,
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once the maximum is reached, further connection attempts will be
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queued up until an existing child process exits.
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This also works
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in the case of
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.Dq wait
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mode, although a value other than one (the
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default) might not make sense in some cases.
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You can also specify the maximum number of connections per minute
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for a given IP address by appending
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a
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.Dq /
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followed by the number to the maximum number of
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outstanding child processes.
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Once the maximum is reached, further
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connections from this IP address will be dropped until the end of the
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minute.
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.Pp
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The
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.Em user
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entry should contain the user name of the user as whom the server
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should run. This allows for servers to be given less permission
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than root.
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Optional
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.Em group
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part separated by
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.Dq \&:
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allows to specify group name different
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than default group for this user.
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Optional
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.Em login-class
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part separated by
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.Dq /
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allows to specify login class different
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than default
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.Dq daemon
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login class.
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.Pp
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The
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.Em server-program
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entry should contain the pathname of the program which is to be
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executed by
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.Nm
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when a request is found on its socket. If
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.Nm
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provides this service internally, this entry should
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be
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.Dq internal .
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.Pp
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The
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.Em server program arguments
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should be just as arguments
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normally are, starting with argv[0], which is the name of
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the program. If the service is provided internally, the
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.Em service-name
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of the service (and any arguments to it) or the word
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.Dq internal
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should take the place of this entry.
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.Pp
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Currently, the only internal service to take arguments is
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.Dq auth .
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Without options, the service will always return
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.Dq ERROR\ : HIDDEN-USER .
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The available arguments to this service that alter its behavior are:
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.Bl -tag -width indent
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.It Fl d Ar fallback
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Provide a
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.Ar fallback
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username.
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If the real
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.Dq auth
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service is enabled
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(with the
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.Fl r
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option discussed below),
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return this username instead of an error
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when look ups fail
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for either socket credentials or the username.
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If the real
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.Dq auth
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service is disabled,
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return this username for every request.
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This is primarily useful when running this service on a NAT machine.
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.It Fl g
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Instead of returning
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the user's name to the ident requester,
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report a
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username made up of random alphanumeric characters,
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e.g.\&
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.Dq c0c993 .
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The
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.Fl g
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flag overrides not only the user names,
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but also any fallback name,
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.Pa .fakeid
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or
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.Pa .noident
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files.
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.It Fl t Xo
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.Ar sec Ns Op . Ns Ar usec
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.Xc
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Specify a timeout for the service.
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The default timeout is 10.0 seconds.
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.It Fl r
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Offer a real
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.Dq auth
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service, as per RFC 1413.
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All the remaining flags apply only in this case.
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.It Fl i
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Return numeric user IDs instead of usernames.
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.It Fl f
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If the file
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.Pa .fakeid
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exists in the home directory of the identified user, report the username
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found in that file instead of the real username.
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If the username found in
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.Pa .fakeid
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is that of an existing user,
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then the real username is reported.
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If the
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.Fl i
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flag is also given then the username in
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.Pa .fakeid
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is checked against existing user IDs instead.
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.It Fl F
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same as
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.Fl f
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|
but without the restriction that the username in
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.Pa .fakeid
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must not match an existing user.
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.It Fl n
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If the file
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.Pa .noident
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exists in the home directory of the identified user, return
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.Dq ERROR\ : HIDDEN-USER .
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This overrides any
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.Pa fakeid
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file which might exist.
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.It Fl o Ar osname
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|
Use
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.Ar osname
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|
instead of the name of the system as reported by
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|
.Xr uname 3 .
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|
.El
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.Pp
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|
The
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.Nm
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program
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also provides several other
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.Dq trivial
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services internally by use of
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routines within itself. These services are
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.Dq echo ,
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|
.Dq discard ,
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|
.Dq chargen
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|
(character generator),
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|
.Dq daytime
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|
(human readable time), and
|
|
.Dq time
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|
(machine readable time, in the form of the number of seconds since
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|
midnight, January 1, 1900). All of these services are available in
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|
both TCP and UDP versions; the UDP versions will refuse service if the
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|
request specifies a reply port corresponding to any internal service.
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|
(This is done as a defense against looping attacks; the remote IP address
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is logged.)
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|
For details of these services, consult the
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appropriate
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|
.Tn RFC
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|
document.
|
|
.Pp
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|
The TCPMUX-demultiplexing service is also implemented as an internal service.
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|
For any TCPMUX-based service to function, the following line must be included
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|
in
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|
.Pa inetd.conf :
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|
.Bd -literal -offset indent
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|
tcpmux stream tcp nowait root internal
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|
.Ed
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|
.Pp
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|
When given the
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|
.Fl l
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|
option
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|
.Nm
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|
will log an entry to syslog each time a connection is accepted, noting the
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|
service selected and the IP-number of the remote requester if available.
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|
Unless otherwise specified in the configuration file,
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and in the absence of the
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.Fl W
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|
and
|
|
.Fl w
|
|
options,
|
|
.Nm
|
|
will log to the
|
|
.Dq daemon
|
|
facility.
|
|
.Pp
|
|
The
|
|
.Nm
|
|
program
|
|
rereads its configuration file when it receives a hangup signal,
|
|
.Dv SIGHUP .
|
|
Services may be added, deleted or modified when the configuration file
|
|
is reread.
|
|
Except when started in debugging mode,
|
|
.Nm
|
|
records its process ID in the file
|
|
.Pa /var/run/inetd.pid
|
|
to assist in reconfiguration.
|
|
.Sh IMPLEMENTATION NOTES
|
|
.Ss TCP Wrappers
|
|
When given the
|
|
.Fl w
|
|
option,
|
|
.Nm
|
|
will wrap all services specified as
|
|
.Dq stream nowait
|
|
or
|
|
.Dq dgram
|
|
except for
|
|
.Dq internal
|
|
services.
|
|
If the
|
|
.Fl W
|
|
option is given, such
|
|
.Dq internal
|
|
services will be wrapped.
|
|
If both options are given, wrapping for both
|
|
internal and external services will be enabled.
|
|
Either wrapping option
|
|
will cause failed connections to be logged to the
|
|
.Dq auth
|
|
syslog facility.
|
|
Adding the
|
|
.Fl l
|
|
flag to the wrapping options will include successful connections in the
|
|
logging to the
|
|
.Dq auth
|
|
facility.
|
|
.Pp
|
|
Note that
|
|
.Nm
|
|
only wraps requests for a
|
|
.Dq wait
|
|
service while no servers are available to service requests.
|
|
Once a
|
|
connection to such a service has been allowed,
|
|
.Nm
|
|
has no control
|
|
over subsequent connections to the service until no more servers
|
|
are left listening for connection requests.
|
|
.Pp
|
|
When wrapping is enabled, the
|
|
.Pa tcpd
|
|
daemon is not required, as that functionality is builtin.
|
|
For more information on TCP Wrappers, see the relevant documentation
|
|
.Pq Xr hosts_access 5 .
|
|
When reading that document, keep in mind that
|
|
.Dq internal
|
|
services have no associated daemon name.
|
|
Therefore, the service name
|
|
as specified in
|
|
.Pa inetd.conf
|
|
should be used as the daemon name for
|
|
.Dq internal
|
|
services.
|
|
.Ss TCPMUX
|
|
.Tn RFC 1078
|
|
describes the TCPMUX protocol:
|
|
``A TCP client connects to a foreign host on TCP port 1. It sends the
|
|
service name followed by a carriage-return line-feed <CRLF>. The
|
|
service name is never case sensitive. The server replies with a
|
|
single character indicating positive (+) or negative (\-)
|
|
acknowledgment, immediately followed by an optional message of
|
|
explanation, terminated with a <CRLF>. If the reply was positive,
|
|
the selected protocol begins; otherwise the connection is closed.''
|
|
The program is passed the TCP connection as file descriptors 0 and 1.
|
|
.Pp
|
|
If the TCPMUX service name begins with a
|
|
.Dq + ,
|
|
.Nm
|
|
returns the positive reply for the program.
|
|
This allows you to invoke programs that use stdin/stdout
|
|
without putting any special server code in them.
|
|
.Pp
|
|
The special service name
|
|
.Dq help
|
|
causes
|
|
.Nm
|
|
to list TCPMUX services in
|
|
.Pa inetd.conf .
|
|
.Ss IPsec
|
|
The implementation includes a tiny hack
|
|
to support IPsec policy settings for each socket.
|
|
A special form of comment line, starting with
|
|
.Dq Li #@ ,
|
|
is interpreted as a policy specifier.
|
|
Everything after the
|
|
.Dq Li #@
|
|
will be used as an IPsec policy string,
|
|
as described in
|
|
.Xr ipsec_set_policy 3 .
|
|
Each
|
|
policy specifier is applied to all the following lines in
|
|
.Pa inetd.conf
|
|
until the next policy specifier.
|
|
An empty policy specifier resets the IPsec policy.
|
|
.Pp
|
|
If an invalid IPsec policy specifier appears in
|
|
.Pa inetd.conf ,
|
|
.Nm
|
|
will provide an error message via the
|
|
.Xr syslog 3
|
|
interface and abort execution.
|
|
.Ss Ux Domain Sockets
|
|
In addition to running services on IP sockets,
|
|
.Nm
|
|
can also manage
|
|
.Ux
|
|
domain sockets.
|
|
To do this you specify a
|
|
.Em protocol
|
|
of
|
|
.Dq unix
|
|
and specify the
|
|
.Ux
|
|
domain socket as the
|
|
.Em service-name .
|
|
The
|
|
.Em service-type
|
|
may be
|
|
.Dq stream
|
|
or
|
|
.Dq dgram .
|
|
The specification of the socket must be
|
|
an absolute path name,
|
|
optionally prefixed by an owner and mode
|
|
of the form
|
|
.Em :user:group:mode: .
|
|
The specification:
|
|
.Pp
|
|
.Dl ":news:daemon:220:/var/run/sock"
|
|
.Pp
|
|
creates a socket owned
|
|
by user
|
|
.Dq news
|
|
in group
|
|
.Dq daemon
|
|
with permissions allowing only that user and group to connect.
|
|
The default owner is the user that
|
|
.Nm
|
|
is running as.
|
|
The default mode only allows the socket's owner to connect.
|
|
.Pp
|
|
.Sy WARNING :
|
|
while creating
|
|
.Ux
|
|
domain socket,
|
|
.Nm
|
|
must change the ownership and permissions on the socket.
|
|
This can only be done securely if
|
|
the directory in which the socket is created
|
|
is writable only by root.
|
|
Do
|
|
.Em NOT
|
|
use
|
|
.Nm
|
|
to create sockets in world writable directories,
|
|
such as
|
|
.Pa /tmp ,
|
|
instead use
|
|
.Pa /var/run
|
|
or a similar directory.
|
|
.Pp
|
|
Internal services may be run on
|
|
.Ux
|
|
domain sockets, in the usual way.
|
|
In this case
|
|
the name of the internal service
|
|
is determined using
|
|
the last component of the socket's pathname.
|
|
.Sh "FILES"
|
|
.Bl -tag -width /var/run/inetd.pid -compact
|
|
.It Pa /etc/inetd.conf
|
|
configuration file
|
|
.It Pa /etc/rpc
|
|
translation of service names to RPC program numbers
|
|
.It Pa /etc/services
|
|
translation of service names to port numbers
|
|
.It Pa /var/run/inetd.pid
|
|
the pid of the currently running
|
|
.Nm
|
|
.El
|
|
.Sh "EXAMPLES"
|
|
.Pp
|
|
Here are several example service entries for the various types of services:
|
|
.Bd -literal
|
|
ftp stream tcp nowait root /usr/libexec/ftpd ftpd -l
|
|
ntalk dgram udp wait root /usr/libexec/ntalkd ntalkd
|
|
telnet stream tcp6 nowait root /usr/libexec/telnetd telnetd
|
|
shell stream tcp46 nowait root /usr/libexec/rshd rshd
|
|
tcpmux/+date stream tcp nowait guest /bin/date date
|
|
tcpmux/phonebook stream tcp nowait guest /usr/local/bin/phonebook phonebook
|
|
rstatd/1-3 dgram rpc/udp wait root /usr/libexec/rpc.rstatd rpc.rstatd
|
|
/var/run/echo stream unix nowait root internal
|
|
#@ ipsec ah/require
|
|
chargen stream tcp nowait root internal
|
|
#@
|
|
.Ed
|
|
.Sh "ERROR MESSAGES"
|
|
The
|
|
.Nm
|
|
server
|
|
logs error messages using
|
|
.Xr syslog 3 .
|
|
Important error messages and their explanations are:
|
|
.Pp
|
|
.Bl -ohang -compact
|
|
.It Xo
|
|
.Ar service Ns / Ns Ar protocol
|
|
.No "server failing (looping), service terminated."
|
|
.Xc
|
|
The number of requests for the specified service in the past minute
|
|
exceeded the limit.
|
|
The limit exists to prevent a broken program
|
|
or a malicious user from swamping the system.
|
|
This message may occur for several reasons:
|
|
.Bl -enum -offset indent
|
|
.It
|
|
There are many hosts requesting the service within a short time period.
|
|
.It
|
|
A broken client program is requesting the service too frequently.
|
|
.It
|
|
A malicious user is running a program to invoke the service in
|
|
a denial-of-service attack.
|
|
.It
|
|
The invoked service program has an error that causes clients
|
|
to retry quickly.
|
|
.El
|
|
.Pp
|
|
Use the
|
|
.Fl R Ar rate
|
|
option,
|
|
as described above, to change the rate limit.
|
|
Once the limit is reached, the service will be
|
|
reenabled automatically in 10 minutes.
|
|
.Pp
|
|
.It Xo
|
|
.Ar service Ns / Ns Ar protocol :
|
|
.No \&No such user
|
|
.Ar user ,
|
|
.No service ignored
|
|
.Xc
|
|
.It Xo
|
|
.Ar service Ns / Ns Ar protocol :
|
|
.No getpwnam :
|
|
.Ar user :
|
|
.No \&No such user
|
|
.Xc
|
|
No entry for
|
|
.Ar user
|
|
exists in the
|
|
.Xr passwd 5
|
|
database.
|
|
The first message
|
|
occurs when
|
|
.Nm
|
|
(re)reads the configuration file.
|
|
The second message occurs when the
|
|
service is invoked.
|
|
.Pp
|
|
.It Xo
|
|
.Ar service :
|
|
.No can't set uid
|
|
.Ar uid
|
|
.Xc
|
|
.It Xo
|
|
.Ar service :
|
|
.No can't set gid
|
|
.Ar gid
|
|
.Xc
|
|
The user or group ID for the entry's
|
|
.Ar user
|
|
field is invalid.
|
|
.Pp
|
|
.It "setsockopt(SO_PRIVSTATE): Operation not supported"
|
|
The
|
|
.Nm
|
|
program attempted to renounce the privileged state associated with a
|
|
socket but was unable to.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr ipsec_set_policy 3 ,
|
|
.Xr hosts_access 5 ,
|
|
.Xr hosts_options 5 ,
|
|
.Xr login.conf 5 ,
|
|
.Xr passwd 5 ,
|
|
.Xr rpc 5 ,
|
|
.Xr services 5 ,
|
|
.Xr comsat 8 ,
|
|
.Xr fingerd 8 ,
|
|
.Xr ftpd 8 ,
|
|
.Xr rexecd 8 ,
|
|
.Xr rlogind 8 ,
|
|
.Xr rpcbind 8 ,
|
|
.Xr rshd 8 ,
|
|
.Xr telnetd 8 ,
|
|
.Xr tftpd 8
|
|
.Rs
|
|
.%A Michael C. St. Johns
|
|
.%T Identification Protocol
|
|
.%O RFC1413
|
|
.Re
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
command appeared in
|
|
.Bx 4.3 .
|
|
TCPMUX is based on code and documentation by Mark Lottor.
|
|
Support for
|
|
.Tn "ONC RPC"
|
|
based services is modeled after that
|
|
provided by
|
|
.Tn SunOS
|
|
4.1.
|
|
The IPsec hack was contributed by the KAME project in 1999.
|
|
The
|
|
.Fx
|
|
TCP Wrappers support first appeared in
|
|
.Fx 3.2 .
|