NetBSD and atomic fragments

[Loganaden Velvindron <logan%elandsys.com@localhost>]

Hi folks,

Going through fgont's draft:
https://tools.ietf.org/html/draft-ietf-6man-deprecate-atomfrag-generation-00

Quote:
   The following text from Section 5 of [RFC2460]:

      "In response to an IPv6 packet that is sent to an IPv4 destination
      (i.e., a packet that undergoes translation from IPv6 to IPv4), the
      originating IPv6 node may receive an ICMP Packet Too Big message
      reporting a Next-Hop MTU less than 1280.  In that case, the IPv6
      node is not required to reduce the size of subsequent packets to
      less than 1280, but must include a Fragment header in those
      packets so that the IPv6-to-IPv4 translating router can obtain a
      suitable Identification value to use in resulting IPv4 fragments.
      Note that this means the payload may have to be reduced to 1232
      octets (1280 minus 40 for the IPv6 header and 8 for the Fragment
      header), and smaller still if additional extension headers are
      used."

   is formally replaced with:

      "An IPv6 node that receives an ICMPv6 Packet Too Big error message
      that reports a Next-Hop MTU smaller than 1280 bytes (the minimum
      IPv6 MTU) MUST NOT include a Fragment header in subsequent packets
      sent to the corresponding destination.  That is, IPv6 nodes MUST
      NOT generate IPv6 atomic fragments."


Tentative diff:

--- ip6_output.c.orig	2015-01-22 00:46:02.998378415 +0000
+++ ip6_output.c	2015-01-22 00:46:34.205044134 +0000
@@ -1230,7 +1230,7 @@ ip6_getpmtu(struct route *ro_pmtu, struc
 			 * (fragment header is needed regardless from the
 			 * packet size, for translators to identify packets)
 			 */
-			alwaysfrag = 1;
+			alwaysfrag = 0;
 			mtu = IPV6_MMTU;
 		} else if (mtu > ifmtu) {
 			/*


Feedback welcomed.