1 .\" Copyright (c) 2000 David A. Holland.
2 .\" All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
7 .\" 1. Redistributions of source code must retain the above copyright
8 .\" notice, this list of conditions and the following disclaimer.
9 .\" 2. Redistributions in binary form must reproduce the above copyright
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12 .\" 3. All advertising materials mentioning features or use of this software
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14 .\" This product includes software developed by David A. Holland.
15 .\" 4. Neither the name of the Author nor the names of any contributors
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31 .\" $Id: telnetlogin.8,v 1.1 2000/10/13 20:54:20 ysato Exp $
35 .Os "Linux NetKit (0.17)"
38 .Nd login wrapper for telnetd
45 is a setuid wrapper that runs
47 It is meant to be invoked by
49 the idea is to remove the necessity of running telnetd as root.
52 should be installed mode 4750, user root, group telnetd. Then,
53 telnetd may be run from
55 as user ``nobody'', group ``telnetd'', and with the option
56 .Fl L Ar path-to-telnetlogin .
59 accepts only the subset of options to
61 shown above, in the order listed. This is the order
63 normally provides them in.
65 also only accepts the environment variables
71 It also insists that the standard input, output, and error streams are
72 open on a terminal, and that it is the process group leader of the
73 foreground process of that terminal. After checking all of these
74 conditions, checking the values of the above environment variables for
75 reasonable values, resetting signal handlers, and so forth, it execs
86 option to login, and does not permit passing a username, so will not
87 work with telnetds that perform authentication via Kerberos or SSL.
89 THIS IS PRESENTLY EXPERIMENTAL CODE; USE WITH CAUTION.
92 was written during the development of NetKit 0.17.