xref: /dragonfly/libexec/fingerd/fingerd.8 (revision dc71b7ab)
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28.\"     @(#)fingerd.8	8.1 (Berkeley) 6/4/93
29.\" $FreeBSD: src/libexec/fingerd/fingerd.8,v 1.14 2005/01/18 09:29:39 ru Exp $
30.\" $DragonFly: src/libexec/fingerd/fingerd.8,v 1.5 2007/11/23 23:16:36 swildner Exp $
31.\"
32.Dd June 4, 1993
33.Dt FINGERD 8
34.Os
35.Sh NAME
36.Nm fingerd
37.Nd remote user information server
38.Sh SYNOPSIS
39.Nm
40.Op Fl s
41.Op Fl l
42.Op Fl p Ar filename
43.Sh DESCRIPTION
44The
45.Nm
46utility uses a simple protocol based on
47.%T RFC 1196
48that provides an interface to
49.Xr finger 1
50at several network sites.
51It is supposed to return a friendly,
52human-oriented status report on either the system at the moment
53or a particular person in depth.
54There is no required format and the
55protocol consists mostly of specifying a single
56.Dq "command line" ,
57thus,
58.Nm
59can also be used to implement other protocols in conjunction with the
60.Fl p
61flag.
62.Pp
63The
64.Nm
65utility is started by
66.Xr inetd 8 ,
67which listens for
68.Tn TCP
69requests at port 79.
70Once connected it reads a single command line
71terminated by a
72.Aq Tn CRLF
73which is passed to
74.Xr finger 1 .
75The
76.Nm
77utility closes its connections as soon as the output is finished.
78.Pp
79If the line is null (i.e., just a
80.Aq Tn CRLF
81is sent) then
82.Xr finger 1
83returns a
84.Dq default
85report that lists all people logged into
86the system at that moment.
87.Pp
88If a user name is specified (e.g.\&
89.Pf eric Aq Tn CRLF )
90then the
91response lists more extended information for only that particular user,
92whether logged in or not.
93Allowable
94.Dq names
95in the command line include both
96.Dq login names
97and
98.Dq user names .
99If a name is ambiguous, all possible derivations are returned.
100.Pp
101The following options may be passed to
102.Nm
103as server program arguments in
104.Pa /etc/inetd.conf :
105.Bl -tag -width indent
106.It Fl s
107Enable secure mode.
108Queries without a user name are rejected and
109forwarding of queries to other remote hosts is denied.
110.It Fl l
111Enable logging.
112The name of the host originating the query is reported via
113.Xr syslog 3
114at LOG_NOTICE priority.
115.It Fl p
116Use an alternate program as the local information provider.
117The default local program
118executed by
119.Nm
120is
121.Xr finger 1 .
122By specifying a customized local server,
123this option allows a system manager
124to have more control over what information is
125provided to remote sites.
126If
127.Fl p
128is specified,
129.Nm
130will also set the environment variable
131.Ev FINGERD_REMOTE_HOST
132to the name of the host making the request.
133.El
134.Sh SEE ALSO
135.Xr finger 1 ,
136.Xr inetd 8
137.Sh HISTORY
138The
139.Nm
140utility appeared in
141.Bx 4.3 .
142.Sh BUGS
143Connecting directly to the server from a
144.Tn TIP
145or an equally narrow-minded
146.Tn TELNET Ns \-protocol
147user program can result
148in meaningless attempts at option negotiation being sent to the
149server, which will foul up the command line interpretation.
150The
151.Nm
152utility should be taught to filter out
153.Tn IAC Ns \'s
154and perhaps even respond
155negatively
156.Pq Tn IAC WON'T
157to all option commands received.
158