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Date:	Thu, 12 Jun 2008 22:39:09 -0700
From:	Gary Johnson <garyjohn AT spk DOT agilent DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Bug in ping? ICMP Sequence Number octets are reversed
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I've been using Cygwin's ping (/usr/bin/ping, ping-1.0-1) to do some 
testing of IP over a wireless modem.  In the process, I was trying 
to correlate the icmp_seq values in ping's output with the ICMP 
Sequence Number field values in a log of the IP messages.  What I 
discovered is that the Sequence Number field values increment like 
this:

   0x0000
   0x0100
   0x0200
   0x0300
   ...
   0xfe00
   0xff00
   0x0001
   0x0101
   0x0201
   ...

It looks like someone just wrote a short integer to the sequence 
number field without calling htons() to perform the possible 
little-endian to big-endian conversion.

Granted, RFC 792 doesn't specify how this number is to be 
incremented, and the current behavior is consistent with Windows' 
ping, but this behavior just doesn't seem right.  It also makes is 
slightly more of a pain to correlate my IP log to ping's display.  I 
would compare it to ping on other systems, but I don't have a 
convenient way to sniff those packets.

Regards,
Gary


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