It was only used in a single place, and did not implement an errdef;
the type itself was not used as sentinel error.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Traditionally when Linux receives remote packets with daddr set to a
loopback address, it reject them as 'martians'. However, when a NAT rule
is applied through iptables this doesn't happen. Our current DNAT rule
used to map host ports to containers is applied unconditionally, even
for such 'martian' packets.
This means a neighbor host (ie. a host connected to the same L2
segment) can send packets to a port mapped on a loopback address. The
purpose of publishing on a loopback address is to make ports
inaccessible to remote hosts -- lack of proper filtering defeats that.
This commit adds an iptables rule to the raw-PREROUTING chain to drop
packets with a loopback dest address and coming from any interface other
than lo.
To accomodate WSL2 mirrored mode, another rule is inserted beforehand to
specifically accept packets coming from the loopback0 interface.
Signed-off-by: Albin Kerouanton <albinker@gmail.com>
When a NAT-based port mapping is created, the daemon adds a DNAT rule in
nat-DOCKER to replace the dest addr with the container IP. However, the
daemon never sets up rules to filter packets destined directly to the
container port. This allows a rogue neighbor (ie. a host that shares a
L2 segment with the host) to send packets directly to the container on
its container-side exposed port.
For instance, if container port 5000 is mapped to host port 6000, a
neighbor could send packets directly to the container on its port 5000.
Since nat-DOCKER mangles the dest addr, and the nat table forbids DROP
rules, this change adds a new rule in the raw-PREROUTING chain to filter
ingress connections targeting the container's IP address.
This filtering is only done when gw_mode=nat. For the unprotected
variant, no filtering is done.
Signed-off-by: Albin Kerouanton <albinker@gmail.com>
It was only returned in a few places, and not used any different than
a "invalid parameter" error, so let's use a standard errdefs.ErrInvalidParameter
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
It was only returned in a few places, and not used any different than
a "invalid parameter" error, so let's use a standard errdefs.ErrInvalidParameter
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
It was only returned in 1 place, and not used any different than
a "notfound" error, so let's use a standard errdefs.ErrNotFound
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
commit 80c44b4b2e removed uses of this
method and added a comment that it should never be used;
> EndpointByID should *never* be called as it's going to create a 2nd instance
> of an Endpoint. The first one lives in the Sandbox the endpoint is attached to.
> Instead, the endpoint should be retrieved by calling [Sandbox.Endpoints()].
Given that the only use of this method is in tests, we can remove if altogether.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
It was only returned in 2 places, and not used any different than
a "notfound" error, so let's use a standard errdefs.NotFound
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Since commit 933fcc9 (Re-remove the SetKey OCI prestart hook),
the network namespace will be set up before endpoints are
created in most cases, apart from build containers.
So, when possible, create the veth with one end in that netns
to save moving it in later. On my host, that saves about 20ms
for each bridge network a container is connected to.
Signed-off-by: Rob Murray <rob.murray@docker.com>
Prefering Check here over NilError so that all defers
wil be executed, instead of potentially failing on the
first one.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Now a gratuitous/unsolicted ARP is sent, there's no need to
use an IPv4-based MAC address to preserve arp-cache mappings
between an endpoint's IP addresses and its MAC addresses.
Because a random MAC address is used for the default bridge,
it no longer makes sense to derive container IPv6 addresses
from the MAC address. This "postIPv6" behaviour was needed
before IPv6 addresses could be configured, but not now. So,
IPv6 addresses will now be IPAM-allocated on the default
bridge network, just as they are for user-defined bridges.
Signed-off-by: Rob Murray <rob.murray@docker.com>
With randomly-generated MAC addresses going into wider use in the most
commonly used container network drivers, it is imperative to avoid
address collisions. Increase the number of random bits in randomly-
generated MAC addresses from 32 bits to 46 bits.
Signed-off-by: Cory Snider <csnider@mirantis.com>
The default is to send 3 messages at 1s intervals.
That can be overridden in "docker network create" using:
-o com.docker.network.advertise_addr_nmsgs=3
-o com.docker.network.advertise_addr_ms=1000
Or, in daemon.json for each driver:
"default-network-opts": {
"bridge": {
"com.docker.network.advertise_addr_nmsgs": "3",
"com.docker.network.advertise_addr_ms": "1000"
}
}
The allowed range is 0-3 for the number of messages, and
100-2000ms for the interval. Setting nmsgs to 0 disables the
gratuitous ARP/NA messages.
The default bridge will always use the built-in defaults,
it cannot be configured.
Signed-off-by: Rob Murray <rob.murray@docker.com>
