Automatic merge from submit-queue (batch tested with PRs 41672, 42084, 42233, 42165, 42273)
Don't sync IPtables before underlying store/reflector is fully synced
Ref #42108
Build on top of #42108 - only the second commit is unique.
Automatic merge from submit-queue
Extensible Userspace Proxy
This PR refactors the userspace proxy to allow for custom proxy socket implementations.
It changes the the ProxySocket interface to ensure that other packages can properly implement it (making sure all arguments are publicly exposed types, etc), and adds in a mechanism for an implementation to create an instance of the userspace proxy with a non-standard ProxySocket.
Custom ProxySockets are useful to inject additional logic into the actual proxying. For example, our idling proxier uses a custom proxy socket to hold connections and notify the cluster that idled scalable resources need to be woken up.
Also-Authored-By: Ben Bennett bbennett@redhat.com
Automatic merge from submit-queue (batch tested with PRs 42316, 41618, 42201, 42113, 42191)
Support unqualified and partially qualified domain name in DNS query in Windows kube-proxy
**What this PR does / why we need it**:
In Windows container networking, --dns-search is not currently supported on Windows Docker. Besides, even with --dns-suffix, inside Windows container DNS suffix is not appended to DNS query names. That makes unqualified domain name or partially qualified domain name in DNS query not able to resolve.
This PR provides a solution to resolve unqualified domain name or partially qualified domain name in DNS query for Windows container in Windows kube-proxy. It uses well-known Kubernetes DNS suffix as well host DNS suffix search list to append to the name in DNS query. DNS packet in kube-proxy UDP stream is modified as appropriate.
This PR affects the Windows kube-proxy only.
**Special notes for your reviewer**:
This PR is based on top of Anthony Howe's commit 48647fb, 0e37f0a and 7e2c71f which is already included in the PR 41487. Please only review commit b9dfb69.
**Release note**:
```release-note
Add DNS suffix search list support in Windows kube-proxy.
```
Automatic merge from submit-queue (batch tested with PRs 42200, 39535, 41708, 41487, 41335)
Update kube-proxy support for Windows
**What this PR does / why we need it**:
The kube-proxy is built upon the sophisticated iptables NAT rules. Windows does not have an equivalent capability. This introduces a change to the architecture of the user space mode of the Windows version of kube-proxy to match the capabilities of Windows.
The proxy is organized around service ports and portals. For each service a service port is created and then a portal, or iptables NAT rule, is opened for each service ip, external ip, node port, and ingress ip. This PR merges the service port and portal into a single concept of a "ServicePortPortal" where there is one connection opened for each of service IP, external ip, node port, and ingress IP.
This PR only affects the Windows kube-proxy. It is important for the Windows kube-proxy because it removes the limited portproxy rule and RRAS service and enables full tcp/udp capability to services.
**Special notes for your reviewer**:
**Release note**:
```
Add tcp/udp userspace proxy support for Windows.
```
This changes the userspace proxy so that it cleans up its conntrack
settings when a service is removed (as the iptables proxy already
does). This could theoretically cause problems when a UDP service
as deleted and recreated quickly (with the same IP address). As
long as packets from the same UDP source IP and port were going to
the same destination IP and port, the the conntrack would apply and
the packets would be sent to the old destination.
This is astronomically unlikely if you did not specify the IP address
to use in the service, and even then, only happens with an "established"
UDP connection. However, in cases where a service could be "switched"
between using the iptables proxy and the userspace proxy, this case
becomes much more frequent.
This commit makes the userspace proxy keep an ObjectReference to the
service being proxied. This allows the consumers of the `ServiceInfo`
struct, like `ProxySockets` to emit events about or otherwise refer to
the service.
This commit adds a new method for constructing userspace proxiers,
`NewCustomProxier`. `NewCustomProxier` functions identically to
`NewProxier`, except that it allows a custom constructor method to
be passed in to construct instances of ProxySocket.
This commit makes it possible for the `ProxySocket` interface to be
implemented by types outside of the `userspace` package. It mainly just
exposes relevant types and fields as public.
This commit adds a method to the `LoadBalancer` interface in the
userspace proxy which allows consumers of the `LoadBalancer` to check if
it thinks a given service has endpoints available.
This makes it more obvious that they run together and makes the upcoming
rate-limited syncs easier.
Also make test use ints for ports, so it's easier to see when a port is
a literal value vs a name.
This is a weird function, but I didn't want to change any semantics
until the tests are in place. Testing exposed one bug where stale
connections of renamed ports were not marked stale.
There are other things that seem wrong here, more will follow.
Move the feature test to where we are activating the feature, rather
than where we detect locality. This is in service of better tests,
which is in service of less-frequent resyncing, which is going to
require refactoring.
Instead of copying the map, like OnServicesUpdate() used to do and which
was copied into buildServiceMap() to preserve semantics while creating
testcases, start with a new empty map and do deletion checking later.
The API docs say:
// ServiceTypeExternalName means a service consists of only a reference to
// an external name that kubedns or equivalent will return as a CNAME
// record, with no exposing or proxying of any pods involved.
which implies that ExternalName services should be ignored for proxy
purposes.
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