1.\" $OpenBSD: tftpd.8,v 1.5 2015/07/18 05:32:56 mcbride Exp $ 2.\" 3.\" Copyright (c) 1983, 1991 The Regents of the University of California. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" from: @(#)tftpd.8 6.7 (Berkeley) 5/13/91 31.\" 32.Dd $Mdocdate: July 18 2015 $ 33.Dt TFTPD 8 34.Os 35.Sh NAME 36.Nm tftpd 37.Nd DARPA Trivial File Transfer Protocol daemon 38.Sh SYNOPSIS 39.Nm tftpd 40.Op Fl 46cdv 41.Op Fl l Ar address 42.Op Fl p Ar port 43.Op Fl r Ar socket 44.Ar directory 45.Sh DESCRIPTION 46.Nm 47is a server which implements the 48.Tn DARPA 49Trivial File Transfer Protocol. 50.Pp 51The use of 52.Xr tftp 1 53does not require an account or password on the remote system. 54Due to the lack of authentication information, 55.Nm 56will allow only publicly readable files to be accessed. 57Files may be written only if they already exist and are publicly writable, 58unless the 59.Fl c 60flag is specified 61.Pq see below . 62Note that this extends the concept of 63.Dq public 64to include 65all users on all hosts that can be reached through the network; 66this may not be appropriate on all systems, and its implications 67should be considered before enabling TFTP service. 68.Pp 69The server must be started as root, but will chroot to the 70.Ar directory 71specified on the command line and drop privileges to the _tftpd user. 72.Pp 73.Nm tftpd 74always provides random data at the path 75.Pa /etc/random.seed , 76and therefore this path will be ignored inside the 77.Ar directory . 78.Ox 79network bootloaders access this path to harvest entropy during 80kernel load. 81.Pp 82The options are as follows: 83.Bl -tag -width Ds 84.It Fl 4 85Forces 86.Nm 87to use IPv4 addresses only. 88.It Fl 6 89Forces 90.Nm 91to use IPv6 addresses only. 92.It Fl c 93Allow new files to be created; 94otherwise uploaded files must already exist. 95Files are created with default permissions 96allowing anyone to read or write to them. 97.It Fl d 98Do not daemonize. 99If this option is specified, 100.Nm 101will run in the foreground and log 102the client IP, type of request, and filename to stderr. 103.It Fl l Ar address 104Listen on the specified address. 105By default 106.Nm 107listens on wildcard addresses. 108.It Fl p Ar port 109Listen on the specified port. 110By default 111.Nm 112listens on the port indicated in the 113.Ql tftp 114service description; see 115.Xr services 5 . 116.It Fl r Ar socket 117Issue filename rewrite requests to the specified UNIX domain socket. 118.Nm 119will write lines in the format "IP OP filename", terminated by a newline, 120where IP is the client's IP address, and OP is one of "read" or "write". 121.Nm 122expects replies in the format "filename" terminated by a newline. 123All rewrite requests from the daemon must be answered 124(even if it is with the original filename) 125before the TFTP request will continue. 126By default 127.Nm 128does not use filename rewriting. 129.It Fl v 130Log the client IP, type of request, and filename. 131.It Ar directory 132.Xr chroot 2 133to 134.Ar directory 135on startup; 136the remote host is not expected to pass the directory 137as part of the file name to transfer. 138.El 139.Sh SEE ALSO 140.Xr tftp 1 , 141.Xr pxeboot 8 , 142.Xr syslogd 8 , 143.Xr tftp-proxy 8 144.Sh HISTORY 145The 146.Nm 147command was originally a process run via 148.Xr inetd 8 149and appeared in 150.Bx 4.2 . 151It was rewritten for 152.Ox 5.2 153as a persistent non-blocking daemon. 154.Sh BUGS 155Many TFTP clients will not transfer files over 16744448 octets 156.Pq 32767 blocks . 157