k3s/hack/verify-flags
Kubernetes Submit Queue 7e37b895d7 Merge pull request #41417 from luxas/kubeadm_test_token
Automatic merge from submit-queue

kubeadm: Hook up kubeadm against the BootstrapSigner

**What this PR does / why we need it**:

This PR makes kubeadm able to use the BootstrapSigner. 
Depends on a few other PRs I've made, I'll rebase and fix this up after they've merged.

**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**:

Example usage:
```console
lucas@THENINJA:~/luxas/kubernetes$ sudo ./kubeadm init --kubernetes-version v1.7.0-alpha.0.377-2a6414bc914d55
[sudo] password for lucas: 
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[init] Using Kubernetes version: v1.7.0-alpha.0.377-2a6414bc914d55
[init] Using Authorization mode: RBAC
[preflight] Running pre-flight checks
[preflight] Starting the kubelet service
[certificates] Generated CA certificate and key.
[certificates] Generated API server certificate and key.
[certificates] Generated API server kubelet client certificate and key.
[certificates] Generated service account token signing key.
[certificates] Generated service account token signing public key.
[certificates] Generated front-proxy CA certificate and key.
[certificates] Generated front-proxy client certificate and key.
[certificates] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf"
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf"
[apiclient] Created API client, waiting for the control plane to become ready
[apiclient] All control plane components are healthy after 21.301384 seconds
[apiclient] Waiting for at least one node to register and become ready
[apiclient] First node is ready after 8.072688 seconds
[apiclient] Test deployment succeeded
[token-discovery] Using token: 67a96d.02405a1773564431
[apiconfig] Created RBAC rules
[addons] Created essential addon: kube-proxy
[addons] Created essential addon: kube-dns

Your Kubernetes master has initialized successfully!

To start using your cluster, you need to run:
export KUBECONFIG=/etc/kubernetes/admin.conf

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
    http://kubernetes.io/docs/admin/addons/

You can now join any number of machines by running the following on each node:

kubeadm join --token 67a96d.02405a1773564431 192.168.1.115:6443

other-computer $ ./kubeadm join --token 67a96d.02405a1773564431 192.168.1.115:6443
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Trying to connect to API Server "192.168.1.115:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Cluster info signature and contents are valid, will use API Server "https://192.168.1.115:6443"
[discovery] Successfully established connection with API Server "192.168.1.115:6443"
[bootstrap] Detected server version: v1.7.0-alpha.0.377+2a6414bc914d55
[bootstrap] The server supports the Certificates API (certificates.k8s.io/v1beta1)
[csr] Created API client to obtain unique certificate for this node, generating keys and certificate signing request
[csr] Received signed certificate from the API server, generating KubeConfig...
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"

Node join complete:
* Certificate signing request sent to master and response
  received.
* Kubelet informed of new secure connection details.

Run 'kubectl get nodes' on the master to see this machine join.

# Wrong secret!
other-computer $ ./kubeadm join --token 67a96d.02405a1773564432 192.168.1.115:6443
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Trying to connect to API Server "192.168.1.115:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Failed to connect to API Server "192.168.1.115:6443": failed to verify JWS signature of received cluster info object, can't trust this API Server
[discovery] Trying to connect to API Server "192.168.1.115:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Failed to connect to API Server "192.168.1.115:6443": failed to verify JWS signature of received cluster info object, can't trust this API Server
^C

# Poor method to create a cluster-info KubeConfig (a KubeConfig file with no credentials), but...
$ printf "kind: Config\n$(sudo ./kubeadm alpha phas --client-name foo --server https://192.168.1.115:6443 --token foo | head -6)\n" > cluster-info.yaml
$ cat cluster-info.yaml
kind: Config
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: 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
    server: https://192.168.1.115:6443
  name: kubernetes

lucas@THENINJA:~/luxas/kubernetes$ sudo ./kubeadm token list
TOKEN                     TTL         EXPIRES   USAGES                   DESCRIPTION
67a96d.02405a1773564431   <forever>   <never>   authentication,signing   The default bootstrap token generated by 'kubeadm init'.

# Any token with the authentication usage set works as the --tls-bootstrap-token arg here
other-computer $ ./kubeadm join --skip-preflight-checks --discovery-file cluster-info.yaml --tls-bootstrap-token 67a96d.02405a1773564431
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Synced cluster-info information from the API Server so we have got the latest information
[bootstrap] Detected server version: v1.7.0-alpha.0.377+2a6414bc914d55
[bootstrap] The server supports the Certificates API (certificates.k8s.io/v1beta1)
[csr] Created API client to obtain unique certificate for this node, generating keys and certificate signing request
[csr] Received signed certificate from the API server, generating KubeConfig...
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"

Node join complete:
* Certificate signing request sent to master and response
  received.
* Kubelet informed of new secure connection details.

Run 'kubectl get nodes' on the master to see this machine join.

# Delete the RoleBinding that exposes the cluster-info ConfigMap publicly. Now this ConfigMap will be private
lucas@THENINJA:~/luxas/kubernetes$ kubectl -n kube-public edit rolebindings kubeadm:bootstrap-signer-clusterinfo

# This breaks the token joining method
other-computer $ sudo ./kubeadm join --token 67a96d.02405a1773564431 192.168.1.115:6443
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Trying to connect to API Server "192.168.1.115:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Failed to request cluster info, will try again: [User "system:anonymous" cannot get configmaps in the namespace "kube-public". (get configmaps cluster-info)]
[discovery] Failed to request cluster info, will try again: [User "system:anonymous" cannot get configmaps in the namespace "kube-public". (get configmaps cluster-info)]
^C

# But we can still connect using the cluster-info file
other-computer $ sudo ./kubeadm join --skip-preflight-checks --discovery-file /k8s/cluster-info.yaml --tls-bootstrap-token 67a96d.02405a1773564431
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Could not access the cluster-info ConfigMap for refreshing the cluster-info information, but the TLS cert is valid so proceeding...
[discovery] The cluster-info ConfigMap isn't set up properly (no kubeconfig key in ConfigMap), but the TLS cert is valid so proceeding...
[bootstrap] Detected server version: v1.7.0-alpha.0.377+2a6414bc914d55
[bootstrap] The server supports the Certificates API (certificates.k8s.io/v1beta1)
[csr] Created API client to obtain unique certificate for this node, generating keys and certificate signing request
[csr] Received signed certificate from the API server, generating KubeConfig...
[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"

Node join complete:
* Certificate signing request sent to master and response
  received.
* Kubelet informed of new secure connection details.

Run 'kubectl get nodes' on the master to see this machine join.

# What happens if the CA in the cluster-info file and the API Server's CA aren't equal?
# Generated new CA for the cluster-info file, a invalid one for connecting to the cluster
# The new cluster-info file is here:
lucas@THENINJA:~/luxas/kubernetes$ cat cluster-info.yaml
kind: Config
apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: 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
    server: https://192.168.1.115:6443
  name: kubernetes

# Try to join an API Server with the wrong CA
other-computer $ sudo ./kubeadm join --skip-preflight-checks --discovery-file /k8s/cluster-info.yaml --tls-bootstrap-token 67a96d.02405a1773564431
[kubeadm] WARNING: kubeadm is in alpha, please do not use it for production clusters.
[preflight] Skipping pre-flight checks
[preflight] Starting the kubelet service
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.1.115:6443"
[discovery] Failed to validate the API Server's identity, will try again: [Get https://192.168.1.115:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")]
[discovery] Failed to validate the API Server's identity, will try again: [Get https://192.168.1.115:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")]
[discovery] Failed to validate the API Server's identity, will try again: [Get https://192.168.1.115:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")]
[discovery] Failed to validate the API Server's identity, will try again: [Get https://192.168.1.115:6443/api/v1/namespaces/kube-public/configmaps/cluster-info: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes")]
^C
```

**Release note**:

```release-note
```
@jbeda @mikedanese @justinsb @pires @dmmcquay @roberthbailey @dgoodwin
2017-03-04 05:54:16 -08:00
..
OWNERS Adds owners for hack/verify-flags 2017-02-21 11:34:05 -03:00
exceptions.txt Merge pull request #41919 from Cynerva/gkk/kubelet-auth 2017-03-03 16:44:37 -08:00
excluded-flags.txt Move kubemark, skew, upgrade, leak logic into hack/e2e.go 2016-08-09 14:04:19 -07:00
known-flags.txt Merge pull request #41417 from luxas/kubeadm_test_token 2017-03-04 05:54:16 -08:00