Bizzare routing table entry.

[Chuck Swiger]

On Aug 7, 2007, at 3:13 PM, Adam J Richardson wrote:
> Modulok wrote:
>>   0&0xc0a80132       link#1             UCS         0        0   bge0
> <snip>
>> 1. The first entry, it's not IPv4, IPv6 or a MAC address that I've
>> ever seen, what format is it?
>
> Hi Modulok,
>
> It's possible to represent IPv4 addresses as a single number. I  
> don't recall the algorithm for converting that four byte dot- 
> delimited group into an integer, though, so I can't tell you what  
> number it is. Perhaps you can Google the algorithm and do the math  
> to figure out what it is.

aaa.bbb.ccc.ddd => 0xAABBCCDD, where AA = hex(aaa), BB = hex(bbb), etc.
In particular, 0xc0a80132 is the hex equivalent of 192.168.1.50.

An IP address + netmask can normally be represented in the routing  
table via the slash notation-- say 192.168.1.50/24 meaning a  
255.255.255.0 (or 0xffffff00) netmask.  Non-contiguous netmasks are  
represented by "address & netmask", but since no normal network ever  
uses such a netmask, they almost always represent a  
misconfiguration-- someone confused the arguments such that the route  
command interpreted the gateway IP as a netmask instead.

-- 
-Chuck