Re: Socket type SOCK_RAW

[Scott Klement <c400-l@xxxxxxxxxxxxxxxx>]

Hi Boris,

I don't remember the reason _why_ this was done, but back in the V4R4 
release, IBM decided to disable specifying these protocol numbers for 
raw sockets.   I remember it, because it broke my traceroute utility 
(that required the ability to specify some extra data in a UDP datagram)

When I complained to IBM about breaking backward compatibility by 
disabling this functionality, they issued PTFs for V4R4 and V4R5.  With 
V5R1, IBM provided their own traceroute utility, and told everyone to 
use that, instead. :-)

Again, I don't remember why they did this -- but I suspect that they 
figured it made it more secure, since people can no longer spoof IP 
addresses and stuff like that.



On 7/2/2012 7:10 PM, Boris wrote:
> Hi Everybody,
> Does anybody have more information or refer to the relevant sources
> regarding why the following call is not supported on the 400?:
> socket(PF_INET, SOCK_RAW, IPPROTO_TCP)
>
> The help text doesn't say much:
> When the socket type is SOCK_RAW, you can specify any protocol number
> between 0-255. Two exceptions are the IPPROTO_TCP and IPPROTO_UDP protocols,
> which cannot be specified on a socket type of SOCK_RAW (if you issue
> socket(), you get an error with an error code of [EPROTONOSUPPORT])
>
> Thanks