Messages in this thread | | | Date | Wed, 23 Jul 2003 14:26:41 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | Re: ICMP REQUEST |
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On Wed, 23 Jul 2003, jw schultz wrote:
> On Wed, Jul 23, 2003 at 12:53:35PM +0530, Hemanshu Kanji Bhadra, Noida wrote: > > Hi, All > > > > i am developing a ping program, through my program I get ECHO_REPLY..but I > > dont get ECHO_REQUEST. > > > > is that the ECHO_REQUEST is handled by kernel.? > > > > please respond as it is urgent. > > In most cases ICMP ECHO_REQUEST is handled by the NIC. The > kernel doesn't even see it. That is why you can ping a > crashed system; the NIC is still configured. >
No. It may be handled entirely in an interrupt service routine, but never by the hardware alone, even the "smart" hardware that does IP checksumming. There isn't enough information available. The echo request contains the IP that the caller seeks to respond. The responder needs to know, not only its IP address, but also the IP address of all the IPs it's going to ARP (proxy ARP).
Cheers, Dick Johnson Penguin : Linux version 2.4.20 on an i686 machine (797.90 BogoMips). Note 96.31% of all statistics are fiction.
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