> - this bit seems odd to me:
> 
> ---8<---
> ... Note that IPv4
> and IPv6 are considered as independent resources, so that
> specification of an IPv4 address via zonecfg(1m) does not place any
> constraints on permissible IPv6 addresses, and vice-versa.
> ---8<---
> 
>   ipv4 and ipv6 addresses are considered independent resources from a
>   zonecfg(1m) perspective, but from a systems management perspective
>   they don't seem that different to me.  to me, it seems that once an
>   admin decides to restrict what addresses can be used on a given
>   interface, that restriction should apply to both ipv4 and ipv6

I could go either way on this.. one interpretation of specifying
only ipv4 addresses in zonecfg would be "ipv6-addrs are dont-cares".
Another is that "ipv6-addrs are forbidden".  I've somewhat arbitrarily
selected the former interpretation, but could just as easily go with
the latter.

>   addresses.  for example, with the current mechanism, if an admin want
>   to prevent the zone from configuring any ipv6 address, how do they go
>   about doing this?

Currently, none, though the  "only ipv4 specified implies ipv6-addrs
are forbidden" approach solves that.  In retrospect,  that choices
seems simpler and cleaner. Is that preferable?


> - does the existence of a zonecfg(1m) defrouter property on an interface
>   prevent a zone from changing the default router for that given
>   interface?

No.  

> - does the existence of a zonecfg(1m) defrouter property on an interface
>   prevent a zone from adding additional routes on a given interface?

No.

Note that, even though a shared-IP zone cannot add routes today, there's
really nothing that constrains it to using the routes specified in the
routing table- it could easily circumvent the routing table by using
IP source-routes, or by using IP*NEXTHOP or IP*PKTINFO socket options.
So preventing the addition of routes doesn't actually achieve any
limitations.

> - can exclusive stack zones manipulate arp tables?  
yes.


> if so, does use of
>   the zonecfg(1m) defrouter property restrict arp table manipulation in
>   any way?  (i'm wondering if arp table manipulation could be used to
>   step around any potential routing limitations placed on an interface.)

there are many ways to step around routing limitations even with shared-IP
today, so not sure what limitations you have in mind.
Basically, regardless of what the routing table has, a node can always
send a packet to any onlink router. 

If what we want, is to prevent the NGZ from DOSing some router(s), then
bandwidth controls are a more reliable way to achieve that.

> - can exclusive stack zones manipulate mac addresses on network
>   interfaces?

 yes- they can use 'ifconfig .. ether <..>'.

>  if so, does the use of the zonecfg(1m) address property
>  restrict this in any way?

no, it does not - the address property only clamps dow the IP address,
and makes no promises about the mac address associated with the IP address.

> - the currently proposed DHCP time-out failure isn't that great.  is
>   there a way to improve this failure?  say by returning EPERM for
>   whatever operation it is that's used to initiate DHCP configuration on
>   an interface.

It would be hard to catch all of them because the udp DHCP DISCOVER
could be sent in multiple ways (e.g. as a udp packet, via IP_HDRINCL
etc.)

>  if not it isn't that big of an issue, but as long as we
>   know we're going to fail it's usually nicer not to keep the user
>   waiting...  ;)

--Sowmini

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