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 The address selected for IPv4 DHCP offers is marked with a DHCP flag. We also include a commit to support late binding of interfaces, addresses, and routes. 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. Jon Maloy (13): ip: Introduce unified multi-address data structures ip: Introduce for_each_addr() macro for address iteration fwd: Unify guest accessibility checks with unified address array arp: Check all configured addresses in ARP filtering netlink: Return prefix length for IPv6 addresses in nl_addr_get() conf: Allow multiple -a/--address options per address family ip: Track observed guest IPv4 addresses in unified address array ip: Track observed guest IPv6 addresses in unified address array migrate: Rename v1 address functions to v2 for clarity migrate: Update protocol to v3 for multi-address support dhcp, dhcpv6: Select addresses for DHCP distribution ndp: Support advertising multiple prefixes in Router Advertisement netlink: Add host-side monitoring for late template interface binding arp.c | 15 +- conf.c | 200 +++++++++++++++---------- conf.h | 9 ++ dhcp.c | 30 ++-- dhcp.h | 2 +- dhcpv6.c | 78 +++++++--- dhcpv6.h | 2 +- epoll_type.h | 2 + fwd.c | 263 +++++++++++++++++++++++++-------- fwd.h | 9 ++ inany.h | 3 + ip.h | 5 + isolation.c | 5 + migrate.c | 183 ++++++++++++++++++++--- ndp.c | 134 ++++++++++++----- netlink.c | 401 ++++++++++++++++++++++++++++++++++++++++++++++++++- netlink.h | 3 + passt.c | 5 + passt.h | 104 +++++++++++-- pasta.c | 39 +++-- tap.c | 67 ++++++--- 21 files changed, 1282 insertions(+), 277 deletions(-) -- 2.52.0