NetBSD/usr.bin/tftp/tftp.1

.\"	$NetBSD: tftp.1,v 1.20 2006/07/23 18:01:58 wiz Exp $
.\"
.\" Copyright (c) 1990, 1993, 1994
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)tftp.1	8.2 (Berkeley) 4/18/94
.\"
.Dd July 23, 2006
.Dt TFTP 1
.Os
.Sh NAME
.Nm tftp
.Nd trivial file transfer program
.Sh SYNOPSIS
.Nm
.Op Fl e
.Op Ar host
.Op Ar port
.Sh DESCRIPTION
.Nm
is the user interface to the Internet
.Tn TFTP
(Trivial File Transfer Protocol),
which allows users to transfer files to and from a remote machine.
The remote
.Ar host
(and optional
.Ar port )
may be specified on the command line, in which case
.Nm
uses
.Ar host
(and
.Ar port )
as the default for future transfers (see the
.Cm connect
command below).
.Pp
The optional
.Fl e
argument sets a binary transfer mode as well as setting the extended options
as if
.Cm tout ,
.Cm tsize ,
and
.Cm blksize 65464 ,
had been given.
.Pp
The Multicast TFTP option is supported in open-loop (i.e., "slave-only") mode
based on IETF draft-dion-tftp-multicast-option-01.txt (May 2002), which in
turn was based on RFC2026.
.Sh COMMANDS
Once
.Nm
is running, it issues the prompt
.Ql tftp\*[Gt]
and recognizes the following commands:
.Pp
.Bl -tag -width verbose -compact
.It Cm \&? Ar command-name ...
Print help information.
.Pp
.It Cm ascii
Shorthand for "mode ascii"
.Pp
.It Cm binary
Shorthand for "mode binary"
.Pp
.It Cm blksize Ar blk-size
Set the tftp blksize option to
.Ar blk-size
octets (8-bit bytes).  Since the number of blocks in a tftp
.Cm get
or
.Cm put
is 65535, the default block size of 512 bytes only allows a maximum of
just under 32 megabytes to be transferred.  The value given for
.Ar blk-size
must be between 8 and 65464, inclusive.
Note that many servers will not respect this option.
.Pp
.It Cm connect Ar host-name Op Ar port
Set the
.Ar host
(and optionally
.Ar port )
for transfers.
Note that the
.Tn TFTP
protocol, unlike the
.Tn FTP
protocol,
does not maintain connections between transfers; thus, the
.Cm connect
command does not actually create a connection,
but merely remembers what host is to be used for transfers.
You do not have to use the
.Cm connect
command; the remote host can be specified as part of the
.Cm get
or
.Cm put
commands.
.Pp
.It Cm get Ar filename
.It Cm get Ar remotename localname
.It Cm get Ar file1 file2 ...  fileN
Get a file or set of files from the specified
.Ar sources .
.Ar Source
can be in one of two forms:
a filename on the remote host, if the host has already been specified,
or a string of the form
.Ar hosts:filename
to specify both a host and filename at the same time.
If the latter form is used,
the last hostname specified becomes the default for future transfers.
.Pp
.It Cm mode Ar transfer-mode
Set the mode for transfers;
.Ar transfer-mode
may be one of
.Em ascii
or
.Em binary .
The default is
.Em ascii .
.Pp
.It Cm put Ar file
.It Cm put Ar localfile remotefile
.It Cm put Ar file1 file2 ... fileN remote-directory
Put a file or set of files to the specified
remote file or directory.
The destination
can be in one of two forms:
a filename on the remote host, if the host has already been specified,
or a string of the form
.Ar hosts:filename
to specify both a host and filename at the same time.
If the latter form is used,
the hostname specified becomes the default for future transfers.
If the remote-directory form is used, the remote host is
assumed to be a
.Ux
machine.
If you need to specify IPv6 numeric address to
.Ar hosts ,
wrap them using square bracket like
.Ar [hosts]:filename
to disambiguate the colon.
.Pp
.It Cm quit
Exit
.Nm .
An end of file also exits.
.Pp
.It Cm rexmt Ar retransmission-timeout
Set the per-packet retransmission timeout, in seconds.
.Pp
.It Cm status
Show current status.
.Pp
.It Cm timeout Ar total-transmission-timeout
Set the total transmission timeout, in seconds.
.Pp
.It Cm tout
Toggle the tftp "timeout" option.  If enabled, the client will pass its
.Ar retransmission-timeout
to the server.
Note that many servers will not respect this option.
.Pp
.It Cm trace
Toggle packet tracing.
.Pp
.It Cm tsize
Toggle the tftp "tsize" option.  If enabled, the client will pass and
request the filesize of a file at the beginning of a file transfer.
Note that many servers will not respect this option.
.Pp
.It Cm verbose
Toggle verbose mode.
.El
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.3 .
IPv6 support was implemented by WIDE/KAME project in 1999.
TFTP options were implemented by Wasabi Systems, Inc., in 2003,
and first appeared in
.Nx 2.0 .
Multicast TFTP was implemented by
.An Jared D. McNeill
in 2006, and first appeared in
.Nx 4.0 .
.Sh SECURITY CONSIDERATIONS
Because there is no user-login or validation within
the
.Tn TFTP
protocol, the remote site will probably have some
sort of file-access restrictions in place.
The exact methods are specific to each site and therefore
difficult to document here.