A pod could put any source MAC or address on the wire: weave has no layer-2
anti-spoofing, so a pod with NET_RAW could pose as another pod or as a node's
bridge, on its own node (local bridging never reaches the router) and, through
weave, on others. That undercut every rule that trusts a source MAC or address,
including the egress holder's check of which node a tunnel packet came from.
The CNI plugin now locks the host side of each pod's veth with tc ingress
filters: IPv4 from the pod's MAC and address, ARP speaking for exactly those
(or probing from 0.0.0.0) pass; everything else is dropped before the bridge
sees it. The u32 keys follow iproute2's layout for "ether src" (-8, -4) and
"ip src" (12). ADD fails if the port cannot be locked, so an unlocked pod never
starts. The filters go away with the veth.
Pods attached before this plugin get locked by weave-init: "weaveutil
lock-ports" walks libcni's result cache (each attachment's netns, interface and
address) and locks their ports, leaving locked ones alone. weave-init mounts
the cache and /var/run/netns read-only for it.
TestPortLockInKernel (root) builds a bridge and two pods in throwaway
namespaces and checks what reaches the other pod; reweave/test/portlock runs
the same against a live cluster, across nodes, after checking every port is
locked.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHXzGrsxfkGk8LmwrBbHNZ
EgressService (reweave.levk.dev/v1alpha1, named after a LoadBalancer
Service of class reweave.levk.dev/node-address) makes every pod the
Service selects (by pod IP, never readiness) leave the cluster from the
Service's address, or not at all. spec.emit is explicit: Holder (the only
mode so far) tunnels members' packets to the node holding the address,
which emits them.
The holder (S1's: the one node with the address on an interface) is the
status' sole writer: host, address, and a 512-port block per node in
61000-65535 (above the default ephemeral range), stable across churn.
A member's node SNATs it to address:its-block before it leaves, so the
holder forwards it unchanged and routes replies back by port alone: ip
rules (to address, ipproto tcp/udp, dport block) ahead of the local
table, which moves from 0 to 100, since the address is local on the
holder. Members' packets travel both ways in reweave-eg, an ipip tunnel
between weave bridges (NPC drops new routed packets into weave), with
accept_local and loose rp_filter on that device only.
Members' new connections are classed at the tail of nat PREROUTING,
after kube-proxy's DNAT has ended the nat walk for Services: the pod
network, multicast and the nodes' addresses are not outside. Marked
packets follow a per-member rule to the holder's table (or to an
unreachable one), are SNATed into the tunnel, and a FORWARD guard drops
anything else a member sends outside (other protocols, other ways out).
The tunnel is accepted only from the nodes' bridges, a holder accepts
from it only the blocks' ports, and TCP MSS is clamped into it.
Fail closed throughout: until the holder has published the status,
without a block, with no single holder, or for a pod two EgressServices
select, a member's outside traffic is dropped. The CNI plugin asks
weave-npc to admit every pod (unix socket /run/weave-npc/egress.sock,
conflist "egressAdmission": true, now rewritten when it differs) after
IPAM and before the pod has an interface, so a member's first packet
already leaves from the address; no answer, no pod. weave-npc applies
nothing about egress from caches that are not synced (unless the API is
absent): a restart never strips members' rules.
reweave/test/egress/run.sh checks the design's assertions against a
live cluster; both end-to-end scripts now re-evaluate each check on
every retry (it was expanded once, before the loop).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHXzGrsxfkGk8LmwrBbHNZ
* Module name changed to `github.com/rajch/weave`
* Added environment variable `CHECKPOINT_DISABLE=1` to default manifests, to bypass weaveworks telemetry
The change makes "weave expose" to call the "/expose" HTTP
endpoint implemented in router which exposes the bridge.
Such architectural change required as we need to know whether NPC is
enabled when exposing the bridge and weaver knows this fact the best.
Unfortunately, this change makes impossible to "weave expose"
when weaver is not running.
Fixes#2921, as all errors are now ignored, including `ENOENT`.
This command typically attempts to delete the network interface `eth0` of a container being destroyed by Kubernetes.
If this interface has already been destroyed or is missing for whatever reason, we still want to remove this container's entry from IPAM in order to free associated resources.
- Optimize. Use LinkByName instead of iterating over list of available
links. Linux does not support interfaces with the same names.
- Remove unnecessary indirection in utility functions which return
common.NetDev.
* highlight the need for `weave expose` in CNI/k8s
Fixes#2405
* Extend error message
* rearranged the sentences
weave launch <peer hosts> seems a bit orphaned here maybe include the weave connect command as well, since it's being mentioned.
When running in the AWSVPC mode, we need to do the following:
- Keep the HW TX offloading on.
- Check that the allocated address belongs to the default subnet,
because only one subnet is allowed and it should be the default one.
If it is not possible to determine whether AWSVPC is on, we ignore
all the steps, because the attachment routines have to work
regardless whether the router is running and the AWSVPC detection
is done by querying the /ipinfo/tracker endpoint served by
the router.
Also move netlink and netns code from common to net
Creates interface if not already there
Adds addresses
Move the set link 'up' to after addresses are added
levaliciousandClaude Opus 5.5