It can only be set on a "--internal" network, and the only difference is
that no address is assigned to the bridge. So, there's no route to a
host address.
Signed-off-by: Rob Murray <rob.murray@docker.com>
It's a generic errdefs.ErrInvalidParameter, and the type itself is not
used as sentinel error anywhere.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Before this change, for IPv4:
- sysctl net.ipv4.ip_forward was enabled during bridge driver
initialisation, if:
- not already enabled
- ip-forward=true, and
- iptables=true.
- the filter-FORWARD chain's policy was set to DROP, if the daemon
updated the sysctl.
- if setting the policy failed, the sysctl change was reverted.
But, for IPv6:
- sysctls net.ipv6.conf.[default|all].forwarding were both enabled
when creating the first IPv6-enabled network, if:
- they weren't already enabled,
- ip-forward=true, and
- ip6tables=true.
- the filter-FORWARD chain's policy was set to DROP when creating
an IPv4 enabled bridge network (inc. the default bridge), if:
- ip6tables=true.
- (this happened whether or not the daemon would ever enable
IPv6 forwarding, or even create an IPv6 network.)
The bridge driver no longer needs the default policy to be DROP to
implement its own port-filtering rules. But, enabling IP forwarding
without setting the filter-FORWARD policy to DROP would potentially
be a security risk.
This change aligns IPv4 and IPv6 behaviours:
- only try to set the sysctls when creating a bridge network that
needs them (for IPv4, that's still during daemon init because
the default bridge is IPv4 enabled).
- only check/set the filter-FORWARD policy after updating sysctls.
- if the filter-FORWARD policy can't be set, treat it as an error
and revert sysctl changes.
We enabled ip6tables by default in 27.0. Setting the filter-FORWARD
policy to DROP even when no IPv6 enabled network was created
caused issues for some users. In particular, those running with
iptables=false suddenly got the IPv6 DROP policy enabled (which
broke unrelated services on the host). This change solves that by
only setting the policy when necessary.
Signed-off-by: Rob Murray <rob.murray@docker.com>
The netlink.RouteAdd in setupBridgeIPv6 always failed, because
the bridge is always 'down' when it's called.
Signed-off-by: Rob Murray <rob.murray@docker.com>
setupBridgeIPv6 attempts to add a route to a new network while
the bridge device is 'down', so it always fails (and the route
is added anyway when the bridge is set 'up').
I'm almost sure the RouteAdd can be removed but, this close to
the moby 27.0 release, only sure-enough to demote the log message
from error to debug.
Signed-off-by: Rob Murray <rob.murray@docker.com>
- Remove package variable bridge.bridgeIPv6
- Use netip in more places
- Improve error messages from fixed-cidr-v6 checks
Signed-off-by: Rob Murray <rob.murray@docker.com>
If env var DOCKER_BRIDGE_PRESERVE_KERNEL_LL=1, don't assign fe80::1/64
to a bridge, and don't delete any link local address with prefix fe80::/64.
Signed-off-by: Rob Murray <rob.murray@docker.com>
If IPv6 is enabled for a bridge network, by the time configuration
is applied, the bridge will always have an address. Assert that, by
raising an error when the configuration is validated.
Use that to simplify the logic used to calculate which addresses
should be assigned to a bridge. Also remove a redundant check in
setupGatewayIPv6() and the error associated with it.
Fix unit tests that enabled IPv6, but didn't supply an IPv6 IPAM
address/pool. Before this change, these tests passed but silently
left the bridge without an IPv6 address.
(The daemon already ensured there was an IPv6 address, this change
does not add a new restriction on config at that level.)
Signed-off-by: Rob Murray <rob.murray@docker.com>
Calculate the IPv6 addreesses needed on a bridge, then reconcile them
with the addresses on an existing bridge by deleting then adding as
required.
(Previously, required addresses were added one-by-one, then unwanted
addresses were removed. This meant the daemon failed to start if, for
example, an existing bridge had address '2000:db8::/64' and the config
was changed to '2000:db8::/80'.)
IPv6 addresses are now calculated and applied in one go, so there's no
need for setupVerifyAndReconcile() to check the set of IPv6 addresses on
the bridge. And, it was guarded by !config.InhibitIPv4, which can't have
been right. So, removed its IPv6 parts, and added IPv4 to its name.
Link local addresses, the example given in the original ticket, are now
released when containers are stopped. Not releasing them meant that
when using an LL subnet on the default bridge, no container could be
started after a container was stopped (because the calculated address
could not be re-allocated). In non-default bridge networks using an
LL subnet, addresses leaked.
Linux always uses the standard 'fe80::/64' LL network. So, if a bridge
is configured with an LL subnet prefix that overlaps with it, a config
error is reported. Non-overlapping LL subnet prefixes are allowed.
Signed-off-by: Rob Murray <rob.murray@docker.com>
The github.com/containerd/containerd/log package was moved to a separate
module, which will also be used by upcoming (patch) releases of containerd.
This patch moves our own uses of the package to use the new module.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This makes it easier to spot if code is only used on Linux. Note that "all of"
the bridge driver is Linux-only.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
