Instead of storing the IP address string in virNetwork related
structs, store the parsed virSocketAddr. This will make it
easier to add IPv6 support in the future, by letting driver
code directly check what address family is present
* src/conf/network_conf.c, src/conf/network_conf.h,
src/network/bridge_driver.c: Convert to use virSocketAddr
in virNetwork, instead of char *.
* src/util/bridge.c, src/util/bridge.h,
src/util/dnsmasq.c, src/util/dnsmasq.h,
src/util/iptables.c, src/util/iptables.h: Convert to
take a virSocketAddr instead of char * for any IP
address parameters
* src/util/network.h: Add macros to determine if an address
is set, and what address family is set.
This patch attempts to take advantage of a newly added netfilter
module to correct for a problem with some guest DHCP client
implementations when used in conjunction with a DHCP server run on the
host systems with packet checksum offloading enabled.
The problem is that, when the guest uses a RAW socket to read the DHCP
response packets, the checksum hasn't yet been fixed by the IP stack,
so it is incorrect.
The fix implemented here is to add a rule to the POSTROUTING chain of
the mangle table in iptables that fixes up the checksum for packets on
the virtual network's bridge that are destined for the bootpc port (ie
"dhcpc", ie port 68) port on the guest.
Only very new versions of iptables will have this support (it will be
in the next upstream release), so a failure to add this rule only
results in a warning message. The iptables patch is here:
http://patchwork.ozlabs.org/patch/58525/
A corresponding kernel module patch is also required (the backend of
the iptables patch) and that will be in the next release of the
kernel.
IPtables will seek to preserve the source port unchanged when
doing masquerading, if possible. NFS has a pseudo-security
option where it checks for the source port <= 1023 before
allowing a mount request. If an admin has used this to make the
host OS trusted for mounts, the default iptables behaviour will
potentially allow NAT'd guests access too. This needs to be
stopped.
With this change, the iptables -t nat -L -n -v rules for the
default network will be
Chain POSTROUTING (policy ACCEPT 95 packets, 9163 bytes)
pkts bytes target prot opt in out source destination
14 840 MASQUERADE tcp -- * * 192.168.122.0/24 !192.168.122.0/24 masq ports: 1024-65535
75 5752 MASQUERADE udp -- * * 192.168.122.0/24 !192.168.122.0/24 masq ports: 1024-65535
0 0 MASQUERADE all -- * * 192.168.122.0/24 !192.168.122.0/24
* src/network/bridge_driver.c: Add masquerade rules for TCP
and UDP protocols
* src/util/iptables.c, src/util/iptables.c: Add source port
mappings for TCP & UDP protocols when masquerading.
We don't use this method of reloading rules anymore, so we can just
kill the code.
This simplifies things a lot because we no longer need to keep a
table of the rules we've added.
* src/util/iptables.c: kill iptablesReloadRules()
Long ago we tried to use Fedora's lokkit utility in order to register
our iptables rules so that 'service iptables restart' would
automatically load our rules.
There was one fatal flaw - if the user had configured iptables without
lokkit, then we would clobber that configuration by running lokkit.
We quickly disabled lokkit support, but never removed it. Let's do
that now.
The 'my virtual network stops working when I restart iptables' still
remains. For all the background on this saga, see:
https://bugzilla.redhat.com/227011
* src/util/iptables.c: remove lokkit support
* configure.in: remove --enable-lokkit
* libvirt.spec.in: remove the dirs used only for saving rules for lokkit
* src/Makefile.am: ditto
* src/libvirt_private.syms, src/network/bridge_driver.c,
src/util/iptables.h: remove references to iptablesSaveRules
