tryfrom.1 (2010 09)

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tryfrom(1) tryfrom(1)
NAME
tryfrom, sffinger - utility programs for TCP Wrappers
SYNOPSIS
/usr/bin/tryfrom
/usr/bin/sffinger
DESCRIPTION
tryfrom
This program identifies the end-point details related to a connection. This program must be called via a
remote shell command as shown below. It is used to find out if the hostname and the address are prop-
erly recognized, and also if the username lookup works properly.
# remsh host /usr/bin/tryfrom
tryfrom prints the following output when it is invoked:
client address (%a):
client hostname (%n):
client username (%u):
client info (%c):
server address (%A):
server hostname (%N):
server process (%d):
server info (%s):
The information related to the client describes how the remote host recognizes the client in terms of
address, name and user name. The information related to the server gives the remote host’s details.
See hosts_access (5) manual page for more information on
%letter expressions.
sffinger
This is a wrapper program to the finger(1) client which offers better protection against the possible dam-
age from data sent by the remote
finger server. This command accepts all the options supported by
finger(1).
It is recommended to use this program in the implementation of traps in the access control language of
/etc/hosts.allow and
/etc/hosts.deny. See hosts_access (5) man page for more information on
setting traps.
This program restricts each line length to 128 bytes and total response to a maximum of 100000 bytes.
sffinger uses 60 seconds time-out value in getting the response from the remote host’s
finger server.
AUTHOR
Wietse Venema ([e-mail]),
Department of Mathematics and Computing Science,
Eindhoven University of Technology
Den Dolech 2, P.O. Box 513,
5600 MB Eindhoven, The Netherlands
SEE ALSO
finger(1), tcpd(1M), hosts_access(5).
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1