Previously, kubeadm would use <ip>:<port> to construct a master
endpoint. This works fine for IPv4 addresses, but not for IPv6.
IPv6 requires the ip to be encased in brackets when being joined
to a port with a colon.
This patch updates kubeadm to support wrapping a v6 address with
[] to form the master endpoint url. Since this functionality is
needed in multiple areas, a dedicated util function was created.
Fixes: https://github.com/kubernetes/kubernetes/issues/48227
Automatic merge from submit-queue (batch tested with PRs 49129, 50436, 50417, 50553, 47587)
Revert "Remove old node role label that is not used by kubeadm"
Revert the commit that removed printing of node roles from kubectl.
It sounds like we also need to update the labels we inspect, as these were previously removed. But starting with a clean revert.
Issue #49124
```release-note
NONE
```
This change adds the `--discovery-token-ca-cert-hash` and `--discovery-token-unsafe-skip-ca-verification` flags for `kubeadm join` and corresponding fields on the kubeadm NodeConfiguration struct. These flags configure enhanced TLS validation for token-based discovery.
The enhanced TLS validation works by pinning the public key hashes of the cluster CA. This is done by connecting to the `cluster-info` endpoint initially using an unvalidated/unsafe TLS connection. After the cluster info has been loaded, parsed, and validated with the existing symmetric signature/MAC scheme, the root CA is validated against the pinned public key set. A second request is made using validated/safe TLS using the newly-known CA and the result is validated to make sure the same `cluster-info` was returned from both requests.
This validation prevents a class of attacks where a leaked bootstrap token (such as from a compromised worker node) allows an attacker to impersonate the API server.
This change also update `kubeadm init` to print the correct `--discovery-token-ca-cert-hash` flag in the example `kubeadm join` command it prints at the end of initialization.
Automatic merge from submit-queue
Add --feature-gate flags to kubeadm
**What this PR does / why we need it**:
Adds `--feature-gates` in similar manner to other `cmd` binaries
**Which issue this PR fixes**
https://github.com/kubernetes/kubeadm/issues/323
**Special notes for your reviewer**:
This results in a lot of probably unnecessary feature flags. I'm guessing a lot of kubeadm users will be confused when they see:
```
Flags:
--feature-gates mapStringBool A set of key=value pairs that describe feature gates for alpha/experimental features. Options are:
APIResponseCompression=true|false (ALPHA - default=false)
Accelerators=true|false (ALPHA - default=false)
AdvancedAuditing=true|false (ALPHA - default=false)
AllAlpha=true|false (ALPHA - default=false)
AllowExtTrafficLocalEndpoints=true|false (default=true)
AppArmor=true|false (BETA - default=true)
DebugContainers=true|false (ALPHA - default=false)
DynamicKubeletConfig=true|false (ALPHA - default=false)
DynamicVolumeProvisioning=true|false (ALPHA - default=true)
ExperimentalCriticalPodAnnotation=true|false (ALPHA - default=false)
ExperimentalHostUserNamespaceDefaulting=true|false (BETA - default=false)
LocalStorageCapacityIsolation=true|false (ALPHA - default=false)
PersistentLocalVolumes=true|false (ALPHA - default=false)
PodPriority=true|false (ALPHA - default=false)
RotateKubeletClientCertificate=true|false (ALPHA - default=false)
RotateKubeletServerCertificate=true|false (ALPHA - default=false)
StreamingProxyRedirects=true|false (BETA - default=true)
TaintBasedEvictions=true|false (ALPHA - default=false)
-h, --help help for kubeadm
```
However the feature flags used in the core pkg is global, so I don't think it can be overriden. So we have a few options:
1. Allow these flags for kubeadm
2. Refactor feature pkg to allow granular features
3. Roll our own feature gating for kubeadm
/cc @luxas
Automatic merge from submit-queue (batch tested with PRs 48781, 48817, 48830, 48829, 48053)
kubeadm: Start to remove old envparams
**What this PR does / why we need it**:
Historically, the envparams feature was used as a way to easily debug `kubeadm` while developing it in the v1.3-v1.4 timeframe. Since then some parameters have been hanging around and not being moved into the API as they should have.
Note: This is a temporary step; moving things into the API. Still, the API is gonna change, this is not the end state. But this is better than keeping the envparams.
I'm gonna deal with `KubernetesDir` in the next PR.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes: kubernetes/kubeadm#326
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
@timothysc @pipejakob
Allow to specify a node-name instead of relaying in `os.Hostname()`
This is useful where kubelet use the name given by the cloud-provider to
register the node.
Partially fix: kubernetes/kubeadm#64
Allow to specify a node-name instead of relaying in `os.Hostname()`
This is useful where kubelet use the name given by the cloud-provider to
register the node.
Partially fix: kubernetes/kubeadm#64
Automatic merge from submit-queue
Remove old node role label that is not used by kubeadm
**What this PR does / why we need it**:
This label hasn't been used by kubeadm since v1.5.
v1.5 support was dropped when v1.6 arrived due to a potential security flaw and the earlier alpha status.
So this label hasn't been used for around three months.
It makes sense to remove it in time for v1.8, could already have been done for v1.7
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
@kubernetes/sig-cluster-lifecycle-pr-reviews
Automatic merge from submit-queue
kubeadm: If `--config` is set, don't allow any other option as it won't have effect
If use config in kubeadm init, cann't get other values from other arguments.
`kubeadm init --config=../kubeadm.config --token 447ad3.96cda76e3206fca0 --apiserver-bind-port 6445`
So I think we need to allow get values from command and is prior than cofig file.
Automatic merge from submit-queue
Prepare for move zz_generated_deepcopy.go to k8s.io/api
This is in preparation to move deep copies to with the types to the types repo (see https://github.com/kubernetes/gengo/pull/47#issuecomment-296855818). The init() function is referring the `SchemeBuilder` defined in the register.go in the same packge, so we need to revert the dependency.
This PR depends on https://github.com/kubernetes/gengo/pull/49, otherwise verification will fail.
Automatic merge from submit-queue
Allow configurable etcd options
**What this PR does / why we need it**:
Allows users to set the `--listen-client-urls` and `--advertise-client-urls` flags on etcd binaries for clusters set up with kubeadm.
**Which issue this PR fixes**:
As far as I can tell right now, other nodes in a cluster set up with kubeadm cannot communicate with the etcd static pod running on the master. This is needed in order to set up calico/canal SDN which needs access to a publicly addressable IPv4 _before_ the overlay network and inter-cluster subnet is created.
Addresses https://github.com/kubernetes/features/issues/138 and https://github.com/kubernetes/features/issues/11.
**Release note**:
```release-note
Users can now specify listen and advertise URLs for etcd in a kubeadm cluster
```
