This target is only valid in the
.B nat
table, in the
.B PREROUTING
and
.B OUTPUT
chains, and user-defined chains which are only called from those
chains.  It alters the destination IP address to send the packet to
the machine itself (locally-generated packets are mapped to the
127.0.0.1 address).  It takes one option:
.TP
.BR "--to-ports " "\fIport\fP[-\fIport\fP]"
This specifies a destination port or range of ports to use: without
this, the destination port is never altered.  This is only valid
if the rule also specifies
.B "-p tcp"
or
.BR "-p udp" .