Known issues with MIPL Mobile IPv6 v0.9.5

Issue 1: HAO placement 

Home Address Destination Option should really be added to a new
destination option header specified in Mobile IPv6 spec which should
be placed after routing header(s), but before fragmentation header.
Putting HAO in DO1 works for now, but support for the new placement
should be added to the IPv6 stack.

Solution: Add support for third DO placement in Linux IPv6 stack.
When: v0.9.6

Issue 2: BU and HAO processing

Home Address Destination Option should be only accepted when valid
binding exists, or packet contains a Binding Update.  Now MH is the
next header after HAO and we can easily check nexthdr for MH.  There
could however, be a FH, AH or ESP between HAO and MH.  With current
code, if we receive a packet with sequence HAO|other header|MH(BU), we
mistakenly drop it.

Solution: Add a check after extension header processing whether HAO
was valid.
When: after IPSec support

Issue 3: DHAAD and home registration retries

When Dynamic Home Agent Address Discovery Reply is received MN only
tries to register with the first HA.  Since HAs from a DHAAD reply
must not be added to the home agents list, they should be added to a
separate list.  If registration with the prefered HA fails, additional
HAs should be tried.  When a new DHAAD reply is received, it should
override old one.

Solution: Add new HA candidate list and supporting functions.  This is
already work in progress.
When: v0.9.6

Issue 4: Several Home Addresses

If MN has several home addresses, Return Routability works only for
the first home address.  This is caused by last remnants of old code
not supporting multiple home addresses.

Solution: Fix Care-of address to Home address resolution.
When: v0.9.6
