TFTPD(8) | System Manager's Manual | TFTPD(8) |
tftpd
— Trivial
File Transfer Protocol daemon
tftpd |
[-46cdiv ] [-l
address] [-p
port] [-r
socket] directory |
tftpd
is a server which implements the
Trivial File Transfer Protocol.
The use of tftp(1) does not
require an account or password on the remote system. Due to the lack of
authentication information, tftpd
will allow only
publicly readable files to be accessed. Files may be written only if they
already exist and are publicly writable, unless the
-c
flag is specified (see below). Note that this
extends the concept of “public” to include all users on all
hosts that can be reached through the network; this may not be appropriate
on all systems, and its implications should be considered before enabling
TFTP service.
The server must be started as root, but will chroot to the directory specified on the command line and drop privileges to the _tftpd user.
tftpd
always provides random data at the
path /etc/random.seed, and therefore this path will
be ignored inside the directory.
OpenBSD network bootloaders access this path to
harvest entropy during kernel load.
The options are as follows:
-4
tftpd
to use IPv4 addresses only.-6
tftpd
to use IPv6 addresses only.-c
-d
tftpd
will run in the foreground and log the
client IP, type of request, and filename to stderr.-i
tftpd
falls back on the requested path. Note that
no attempt is made to limit the client to its subdirectory. This option
cannot be combined with -r
.-l
addresstftpd
listens on wildcard addresses.-p
porttftpd
listens on the port indicated in the
‘tftp
’ service description; see
services(5).-r
sockettftpd
will write lines in the format "IP OP
filename", terminated by a newline, where IP is the client's IP
address, and OP is one of "read" or "write".
tftpd
expects replies in the format
"filename" terminated by a newline. All rewrite requests from
the daemon must be answered (even if it is with the original filename)
before the TFTP request will continue. By default
tftpd
does not use filename rewriting. This option
cannot be combined with -i
.-v
K. Sollins, The TFTP Protocol (Revision 2), RFC 1350, July 1992.
G. Malkin and A. Harkin, TFTP Option Extension, RFC 2347, May 1998.
G. Malkin and A. Harkin, TFTP Blocksize Option, RFC 2348, May 1998.
G. Malkin and A. Harkin, TFTP Timeout Interval and Transfer Size Options, RFC 2349, March 1998.
The tftpd
command was originally a process
run via inetd(8) and appeared in
4.2BSD. It was rewritten for
OpenBSD 5.2 as a persistent non-blocking daemon.
Many TFTP clients will not transfer files over 16744448 octets (32767 blocks).
March 4, 2019 | OpenBSD-current |