Gateways of a GatewayClass whose controllerName is reweave.levk.dev/gateway
are served like LoadBalancer Services: a Gateway names one IPv4 address in
spec.addresses, and the node holding that address serves all of it and
writes its status.
- TCP listeners forward the oldest TCPRoute attached to them in the kernel,
through the same DNAT and reply steering as LoadBalancer Services, so the
backend sees the client's own address.
- HTTP and HTTPS listeners are served by the agent itself on the holder:
TLS terminated with the listener's certificate (chosen by SNI, swapped in
place when its Secret changes, HTTP/2 offered), requests routed by the
attached HTTPRoutes in the order the spec prescribes (hostname, exact
path, longest prefix, method, headers, query, age, name, rule), and passed
to a ready endpoint of the backend with X-Forwarded-For built from this
hop only. RequestRedirect, URLRewrite and both header modifiers are
implemented; other filters and regular expressions are refused
(Accepted False, UnsupportedValue). Bodies are streamed, never limited.
Unresolved backends answer 500, backends without ready endpoints 503,
requests nothing matches 404. Those ports are let in ahead of the host
firewall (REWEAVE-LB-IN).
Listeners are checked for protocol, route kinds, certificates (Secrets in
the Gateway's namespace or granted by a ReferenceGrant, and only in the
namespaces the agent may read: --gateway-namespaces, default
gateway-system), conflicts on a port, and ports LoadBalancer Services
already forward. Routes attach by parentRef (sectionName, port),
allowedRoutes (namespaces Same, All or Selector; kinds) and hostname
intersection, with the spec's conditions and reasons.
One writer per status: the holder writes its Gateway's (the first node by
name when nobody holds the address, so failures are reported once), the
first node by name writes GatewayClass and route statuses, keeping other
controllers' route parents. Writes are conditional on the resourceVersion
they were computed from, and a condition keeps its transition time while
its status stands, so an unchanged status is never rewritten.
The types are plain structs for the subset implemented (the upstream module
needs a newer client-go than the fork's); the CRDs are installed apart from
this manifest, which grants the agent read access to the Gateway API kinds,
patch on their status, and Secrets in gateway-system only.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHXzGrsxfkGk8LmwrBbHNZ
A Service of type LoadBalancer with loadBalancerClass
reweave.levk.dev/node-address names its address in spec.loadBalancerIP.
Each node's weave-npc publishes the IPv4 addresses on its host interfaces
and its weave bridge (Node annotations reweave.levk.dev/addresses and
reweave.levk.dev/weave). The one node that holds a Service's address is
its holder: it alone writes status.loadBalancer (ipMode Proxy, so
kube-proxy installs nothing for the address) and DNATs the address's ports
to ready endpoints (EndpointSlices), without SNAT, from nat PREROUTING
ahead of kube-proxy. Every other node marks the connections the holder
forwards to its pods (new, from the holder's bridge MAC, from outside the
pod network) and routes their replies back to the holder's bridge through
a per-holder policy rule and table, so the holder's conntrack undoes the
DNAT and the reply leaves from the address the client connected to.
Fail closed: an address no node holds, or that several nodes hold, is
served by no node, and its status is cleared (by its holder, or by the
first node by name if none holds it). Compute is the policy as a pure
function; Datapath replaces exactly the chains it owns with
iptables-restore --noflush and keeps its rules and tables exact.
weave-npc runs it unless --lb=false; the ClusterRole gains services
(watch), services/status (patch), endpointslices (watch), nodes (patch).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UHXzGrsxfkGk8LmwrBbHNZ
levaliciousandClaude Opus 5.5