Re: Updating to RFC6434 to deal with 8200-style header insertion by IPIP

Michael Richardson <mcr+ietf@sandelman.ca> Wed, 08 November 2017 15:11 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
cc: Tim Chown <Tim.Chown@jisc.ac.uk>, Fernando Gont <fernando@gont.com.ar>, "C. M. Heard" <heard@pobox.com>, 6man WG <ipv6@ietf.org>
Subject: Re: Updating to RFC6434 to deal with 8200-style header insertion by IPIP
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Date: Wed, 08 Nov 2017 10:10:59 -0500
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Brian E Carpenter <brian.e.carpenter@gmail.com> wrote:
    >    Note that it is impossible for a node to distinguish between an
    > unrecognized extension header and an unrecognized upper layer

Does "unrecognized" mean unknown to the writer of the code at the time of
writing, or does it mean a header which the node has no support for?

Or to put it in C, what goes into TBD?

retry:
  switch(proto) {
  case IPPROTO_UDP:
       udp_rcv();
       break;
  case IPPROTO_TCP:
       tcp_rcv();
       break;
  case IPPROTO_AH:
       if(ipsec_enabled) ipsec_rcv();
       else TBD;
  case IPPROTO_HOPOPT:
       process_hopopt();
       goto retry;
  case IPPROTO_MOBILITY_HEADER:
       skip_hopopt();
       goto retry;
  default:
       return_icmp(1);
  }

-- 
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-