if a entry is not route add -net xxx/bits then we should use
the addr (xxx) to establish the number of bits by looking at
the first non-zero bit. So if we enter
route add -net 10.1.1.0 10.1.3.5
this is the same as doing
route add -net 10.1.1.0/24
Since the 8th bit (zero counting) is set to 1 we set bits
to 32-8.
Users can of course still use the /x to change this behavior
or in cases where the network is in the trailing part
of the address, a "netmask" argument can be supplied to
override what is established from the interpretation of the
address itself. e.g:
route add -net 10.1.1.8 -netmask 0xff00ffff
should overide and place the proper CIDR mask in place.
PR: 131365
MFC after: 1 week
7f749ed938