tftp-proxy is a proxy for the Internet Trivial File Transfer Protocol invoked by the
inetd(8) internet server. TFTP connections should be redirected to the proxy using the
pf(4) rdr command, after which the proxy connects to the server on behalf of the client.
The proxy establishes a
pf(4) rdr rule using the
anchor facility to rewrite packets between the client and the server. Once the rule is established,
tftp-proxy forwards the initial request from the client to the server to begin the transfer. After
transwait seconds, the
pf(4) NAT state is assumed to have been established and the
rdr rule is deleted and the program exits. Once the transfer between the client and the server is completed, the NAT state will naturally expire.
Assuming the TFTP command request is from $client to $server, the proxy connected to the server using the $proxy source address, and $port is negotiated,
tftp-proxy adds the following rule to the anchor:
rdr proto udp from $server to $proxy port $port -> $client
The options are as follows:
-v
Log the connection and request information to
syslogd(8).
-w transwait
Number of seconds to wait for the data transmission to begin before removing the
pf(4) rdr rule. The default is 2 seconds.