+++ /dev/null
-.\"
-.\" Copyright (c) 2005 Fredrik Tolf <fredrik@dolda2000.com>
-.\"
-.\" This is free documentation; you can redistribute it and/or
-.\" modify it under the terms of the GNU General Public License as
-.\" published by the Free Software Foundation; either version 2 of
-.\" the License, or (at your option) any later version.
-.\"
-.\" The GNU General Public License's references to "object code"
-.\" and "executables" are to be interpreted as the output of any
-.\" document formatting or typesetting system, including
-.\" intermediate and printed output.
-.\"
-.\" This manual is distributed in the hope that it will be useful,
-.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
-.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-.\" GNU General Public License for more details.
-.\"
-.\" You should have received a copy of the GNU General Public
-.\" License along with this manual; if not, write to the Free
-.\" Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111,
-.\" USA.
-.\"
-.TH IDNLOOKUP 1 "12 Jan 2006" "icmpdn 0.3" "ICMP Hostname Manual"
-.SH NAME
-idnlookup \- ICMP domain name resolver
-.SH SYNOPSIS
-.B idnlookup
-[ \fB-ahT\fP ] [ \fB-t\fP \fItimeout\fP ] \fIhostname\fP
-.SH DESCRIPTION
-\fBidnlookup\fP is a utility to ask an Internet host for its fully
-qualified domain name over ICMP. If successful, it will print the
-host's domain name to standard output.
-.P
-\fIhostname\fP is the address of the Internet host to query. It can be
-either a symbolic hostname, an IPv4 address in decimal notation, or an
-IPv6 address in hexadecimal notation. If a symbolic hostname is
-specified, all its addresses are looked up and tried in order.
-.P
-The remote host must be running software which can respond to the
-requests for hostname. To the knowledge of the author, current
-BSD-based systems can do this in the kernel. Linux systems must, as of
-this writing, be running \fBicmpdnd\fP(8).
-.SH EXIT STATUS
-\fBidnlookup\fP will return 0 if the specified host was succesfully
-queried. If illegal arguments were given, or if the host could, for
-any reason, not be queried, or if another error occurred, it will
-return 1.
-.SH OPTIONS
-.TP
-.B -a
-Normally, \fBidnlookup\fP will only print the first name that the host
-returns. This option will cause all names to be printed, one per
-line.
-.TP
-.B -h
-Print a brief usage message and exit.
-.TP
-.B -T
-Write the time-to-live in seconds that the remote host suggests on the
-first line, before any names.
-.TP
-.B -t
-Print an error message and exit if the remote host does not reply in
-\fItimeout\fP milliseconds. The default is 3 seconds. Note that this
-timeout will apply to all addresses, in case a symbolic hostname
-resolves to more than one address.
-.SH SECURITY
-Since \fBidnlookup\fP uses ICMP, it needs to run as root. Normally, it
-should be installed set-uid root in order for any user to be able to
-ask hosts for their names. Although the author believes
-\fBidnlookup\fP to be safe to install as set-uid root, he makes no
-guarantees.
-.SH BUGS
-\fBidnlookup\fP does not yet implement domain name decompression, and
-as such will scream and die at the sight of such names. This is
-because the author is not sure from which point in the ICMP datagrams
-the offsets specified in compressed domain names is to be counted. If
-you have information on this, please mail the author. Until then, this
-bug will hopefully not pose any large problems, since probably only
-very few hosts will return more than one name, and then there is
-little chance to compress it.
-.P
-Some GNU/Linux distributions still ship with a GNU C library
-implementation that has a bug in the implementation of
-\fBgetaddrinfo\fP(3), which may cause addresses resolved from a
-symbolic hostname to be returned in the wrong order (i.e. not
-consistent with RFC 3484). This will in turn cause \fBidnlookup\fP to
-try addresses in the wrong order, if the hostname in question triggers
-the \fBgetaddrinfo\fP(3) bug. This will normally not pose a problem,
-but not too uncommonly, this will cause IPv4 addresses to be sorted
-before IPv6 addresses. If the remote host listens for ICMP hostname
-requests only on IPv6 (or if the Internet service provider for the
-remote host blocks ICMP packets, which is wrong, but unfortunately not
-all too uncommon), \fBidnlookup\fP will have to time out on the IPv4
-address before being able to query the IPv6 address. This bug has been
-fixed since, but as of this writing, only a few systems run the fixed
-version of glibc.
-.SH NOTES
-The ICMP hostname tools also ship with a nameswitch module for ICMP
-hostname lookups, which can be used to automatically look up hostnames
-over ICMP when a program calls \fBgethostbyaddr\fP(3) or any related
-function. See the \fBnss-icmp\fP(7) man page for more information.
-.SH AUTHOR
-Fredrik Tolf <fredrik@dolda2000.com>
-.SH SEE ALSO
-\fBicmpdnd\fP(8), \fBnss-icmp\fP(7), \fIRFC 1788\fP
Dolda2000 GitWeb / icmp-dn.git / blobdiff