修复kube-proxy证书权限过大问题
修复kube-proxy证书权限过大问题
之前kube-proxy服务都是用admin集群证书，造成权限过大不安全，后续该问题，将在文档中修复
请关注 https://github.com/cby-chen/Kubernetes
创建生成证书配置文件
详细见：https://github.com/cby-chen/Kubernetes#23%E5%88%9B%E5%BB%BA%E8%AF%81%E4%B9%A6%E7%9B%B8%E5%85%B3%E6%96%87%E4%BB%B6
cat > ca-config.json << EOF
{
"signing": {
"default": {
"expiry": "876000h"
},
"profiles": {
"kubernetes": {
"usages": [
"signing",
"key encipherment",
"server auth",
"client auth"
],
"expiry": "876000h"
}
}
}
}
EOF
cat > kube-proxy-csr.json << EOF
{
"CN": "system:kube-proxy",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "Beijing",
"L": "Beijing",
"O": "system:kube-proxy",
"OU": "Kubernetes-manual"
}
]
}
EOF生成 CA 证书和私钥
cfssl gencert \
-ca=/etc/kubernetes/pki/ca.pem \
-ca-key=/etc/kubernetes/pki/ca-key.pem \
-config=ca-config.json \
-profile=kubernetes \
kube-proxy-csr.json | cfssljson -bare /etc/kubernetes/pki/kube-proxy
ll /etc/kubernetes/pki/kube-proxy*
-rw-r--r-- 1 root root 1045 May 26 10:21 /etc/kubernetes/pki/kube-proxy.csr
-rw------- 1 root root 1675 May 26 10:21 /etc/kubernetes/pki/kube-proxy-key.pem
-rw-r--r-- 1 root root 1464 May 26 10:21 /etc/kubernetes/pki/kube-proxy.pem设置集群参数和客户端认证参数时 --embed-certs 都为 true，这会将 certificate-authority、client-certificate 和 client-key 指向的证书文件内容写入到生成的 kube-proxy.kubeconfig 文件中；
kube-proxy.pem 证书中 CN 为 system:kube-proxy，kube-apiserver 预定义的 RoleBinding cluster-admin 将User system:kube-proxy 与 Role system:node-proxier 绑定，该 Role 授予了调用 kube-apiserver Proxy 相关 API 的权限；
创建 kubeconfig 文件
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=https://10.0.0.89:8443 \
--kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig
kubectl config set-credentials kube-proxy \
--client-certificate=/etc/kubernetes/pki/kube-proxy.pem \
--client-key=/etc/kubernetes/pki/kube-proxy-key.pem \
--embed-certs=true \
--kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig
kubectl config set-context kube-proxy@kubernetes \
--cluster=kubernetes \
--user=kube-proxy \
--kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig
kubectl config use-context kube-proxy@kubernetes --kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig无法访问 pod资源
[cby@k8s-master01 ~]$ kubectl get pod
Error from server (Forbidden): pods is forbidden: User "system:kube-proxy" cannot list resource "pods" in API group "" in the namespace "default"
[cby@k8s-master01 ~]$可以访问 node资源
[cby@k8s-master01 ~]$ kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master01 Ready 2d21h v1.24.0
k8s-master02 Ready 2d21h v1.24.0
k8s-master03 Ready 2d21h v1.24.0
k8s-node01 Ready 2d21h v1.24.0
k8s-node02 Ready 2d21h v1.24.0
[cby@k8s-master01 ~]$ 将配置进行替换
for NODE in k8s-master02 k8s-master03; do scp /etc/kubernetes/kube-proxy.kubeconfig $NODE:/etc/kubernetes/kube-proxy.kubeconfig; done
for NODE in k8s-node01 k8s-node02; do scp /etc/kubernetes/kube-proxy.kubeconfig $NODE:/etc/kubernetes/kube-proxy.kubeconfig; done
[root@k8s-master01 ~]# cat /etc/kubernetes/kube-proxy.yaml
apiVersion: kubeproxy.config.k8s.io/v1alpha1
bindAddress: 0.0.0.0
clientConnection:
acceptContentTypes: ""
burst: 10
contentType: application/vnd.kubernetes.protobuf
kubeconfig: /etc/kubernetes/kube-proxy.kubeconfig
qps: 5
clusterCIDR: 172.16.0.0/12,fc00::/48
configSyncPeriod: 15m0s
conntrack:
max: null
maxPerCore: 32768
min: 131072
tcpCloseWaitTimeout: 1h0m0s
tcpEstablishedTimeout: 24h0m0s
enableProfiling: false
healthzBindAddress: 0.0.0.0:10256
hostnameOverride: ""
iptables:
masqueradeAll: false
masqueradeBit: 14
minSyncPeriod: 0s
syncPeriod: 30s
ipvs:
masqueradeAll: true
minSyncPeriod: 5s
scheduler: "rr"
syncPeriod: 30s
kind: KubeProxyConfiguration
metricsBindAddress: 127.0.0.1:10249
mode: "ipvs"
nodePortAddresses: null
oomScoreAdj: -999
portRange: ""
udpIdleTimeout: 250ms
[root@k8s-master01 ~]# systemctl restart kube-proxyhttps://www.oiox.cn/
https://www.chenby.cn/
https://cby-chen.github.io/
https://blog.csdn.net/qq_33921750
https://my.oschina.net/u/3981543
https://www.zhihu.com/people/chen-bu-yun-2
https://segmentfault.com/u/hppyvyv6/articles
https://juejin.cn/user/3315782802482007
https://cloud.tencent.com/developer/column/93230
https://www.jianshu.com/u/0f894314ae2c
https://www.toutiao.com/c/user/token/MS4wLjABAAAAeqOrhjsoRZSj7iBJbjLJyMwYT5D0mLOgCoo4pEmpr4A/
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