[PATCH v7 00/13] Introduce multiple addresses and late binding

[Jon Maloy <jmaloy@redhat.com>]

This series adds handling of multiple addresses into a unified address
array, so that a guest can see the same addresses on his own interface.

o All addresses are stored as union inany_addr
o User configured addresses are marked with a USER flag.
o Host provided addresses are marked with a HOST flag.
o Link local addresses are also marked with a LINKLOCAL flag.
o Addresses the guest is actually using are marked with an OBSERVED flag.
o Addresses eligible for DHCP assignments are marked with an DHCP flag.
o Addresses eligible for DHCPv6 advertisement are marked with an DHCPV6 flag.
o Addresses eligible for NDP advertisement are marked with an NDP flag.

v2:
  - Added the earlier standalone CIDR commit to the head of the series.
  - Replaced the guest namespace interface subscriptions with just
    an address observation feature, so that it works with both PASTA
    and PASST.
  - Unified 'no_copy_addrs' and 'copy_addrs' code paths, as suggested
    by David G.
  - Multiple other changes, also based on feedback from David.
  - Removed the host interface subscription patches, -for now.
    I intend to re-add them once this series is applied.
  - Outstanding question: When do we add an IPv4 link local address
    to the guest? Only in local/opaque mode? Only when
    explicitly requested? Always?

v3:
  - Unified the IPv4 and IPv6 arrays into one array
  - Changed prefix_len to always be in IPv6/IpV4 mapped format
  - Updated migration protocol to v3, handling multiple addresses
  - Many other smaller changes, based on feedback from the PASST team   

v4:
  - Numerous changes based on feedback
  - Added several new commits, mostly broken
    out of the pre-existing ones.

v5: - Re-introduced multiple OBSERVED addresses. This actually
      turned out to be cleaner and with more predictable behaviour
      than allowing only one.
    - Included the DHCP and NDP patches from previous versions,
      improved and updated according to feedback from the team.
    - Likewise re-included the host-side netlink commit to support
      late binding.

v6: - Skipped late binding commit for now.
    - Added commit for using a single print buffer in conf_print
    - Added commit for reading and adding all addresses from
      template interface.
    - Added commit for refactoring pasta_ns_conf().
    - Added separate address flags for DHCP, DHCPv6, and NDP,
      so that those are easy to recognize for their respective
      functions.
    - Split DHCP and DHCPv6 address selection into separate commits.
    - Updated migration protocol to v3 for multi-address support.
    - Numerous other smaller changes, both after feedback from
      David G. and issues I have identified myself.

v7: - Replaced commit #1 with one that fixes a return address
      issue with DHCPv6
    - Modified for_each_addr() macro to take 4 arguments
    - Many more fixes and changes based on feedback and own
      findings.

Jon Maloy (13):
  dhcpv6: Fix reply destination to match client's source address
  passt, pasta: Introduce unified multi-address data structures
  fwd: Unify guest accessibility checks with unified address array
  arp: Check all configured addresses in ARP filtering
  conf: Allow multiple -a/--address options per address family
  netlink, conf: Read all addresses from template interface at startup
  netlink, pasta: refactor function pasta_ns_conf()
  conf, pasta: Track observed guest IPv4 addresses in unified address
    array
  conf, pasta: Track observed guest IPv6 addresses in unified address
    array
  migrate: Update protocol to v3 for multi-address support
  dhcp: Select address for DHCP distribution
  dhcpv6: Select addresses for DHCPv6 distribution
  ndp: Support advertising multiple prefixes in Router Advertisements

 arp.c     |  20 +++-
 conf.c    | 200 ++++++++++++++++++++---------------
 dhcp.c    |  22 ++--
 dhcpv6.c  | 115 +++++++++++---------
 dhcpv6.h  |   2 +-
 fwd.c     | 305 ++++++++++++++++++++++++++++++++++++++++--------------
 fwd.h     |   8 ++
 inany.h   |  44 ++++++++
 ip.h      |   2 +
 migrate.c | 240 ++++++++++++++++++++++++++++++++++++++++--
 ndp.c     | 131 ++++++++++++++++-------
 netlink.c |  70 +++++++------
 netlink.h |   7 +-
 passt.1   |   7 +-
 passt.h   |  78 +++++++++++---
 pasta.c   | 224 ++++++++++++++++++++-------------------
 tap.c     |  37 ++-----
 tap.h     |   2 -
 18 files changed, 1054 insertions(+), 460 deletions(-)

-- 
2.52.0