tftpd is a server that supports the Internet Trivial File Transfer Protocol (TFTP). This server is normally started by inetd(1M) and operates at the port indicated in the tftp Internet service description in the /etc/inetd.conf file. By default, the entry for in.tftpd in etc/inetd.conf is commented out. To make in.tftpd operational, the comment character(s) must be deleted from the file. See inetd.conf(4).
Before responding to a request, the server attempts to change its current directory to homedir; the default directory is /tftpboot.
The use of tftp does not require an account or password on the remote system. Due to the lack of authentication information, in.tftpd will allow only publicly readable files to be accessed. Files may be written only if they already exist and are publicly writable. 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 this service.
in.tftpd runs with the user ID and group ID set to [GU]ID_NOBODY under the assumption that no files exist with that owner or group. However, nothing checks this assumption or enforces this restriction.
Debug. When specified it sets the SO_DEBUG socket option.
Secure. When specified, the directory change to homedir must succeed. The daemon also changes its root directory to homedir.
The in.tftpd server is IPv6–enabled. See ip6(7P).
See attributes(5) for descriptions of the following attributes:
Malkin, G. and Harkin, A. RFC 2347, TFTP Option Extension. The Internet Society. May 1998
Malkin, G. and Harkin, A. RFC 2348, TFTP Blocksize Option. The Internet Society. May 1998
Malkin, G. and Harkin, A. RFC 2349, TFTP Timeout Interval and Transfer Size Options. The Internet Society. May 1998
Sollins, K.R. RFC 1350, The TFTP Protocol (Revision 2). Network Working Group. July 1992.
The tftpd server only acknowledges the transfer size option that is sent with a read request when the octet transfer mode is specified.