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58
docs/02-client-tools.md
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@ -1,72 +1,56 @@
# Installing the Client Tools # Installing the Client Tools
In this lab you will install the command line utilities required to complete this tutorial: [cfssl](https://github.com/cloudflare/cfssl), [cfssljson](https://github.com/cloudflare/cfssl), and [kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl). In this lab you will install the command line utilities required to complete this tutorial: [step](https://github.com/smallstep/cli), and [kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl).
## Install CFSSL ## Install CFSSL
The `cfssl` and `cfssljson` command line utilities will be used to provision a [PKI Infrastructure](https://en.wikipedia.org/wiki/Public_key_infrastructure) and generate TLS certificates. The `step` command line utility will be used to provision a [PKI Infrastructure](https://en.wikipedia.org/wiki/Public_key_infrastructure) and generate TLS certificates.
Download and install `cfssl` and `cfssljson`: Download and install `step`:
### OS X ### OS X
``` For Intel chips:
curl -o cfssl https://storage.googleapis.com/kubernetes-the-hard-way/cfssl/1.4.1/darwin/cfssl
curl -o cfssljson https://storage.googleapis.com/kubernetes-the-hard-way/cfssl/1.4.1/darwin/cfssljson
```
``` ```
chmod +x cfssl cfssljson curl -L https://dl.step.sm/gh-release/cli/gh-release-header/v0.18.0/step_darwin_0.18.0_amd64.tar.gz | tar xz
sudo mv step_0.18.0/bin/step /usr/local/bin/
``` ```
``` For Apple Silicon:
sudo mv cfssl cfssljson /usr/local/bin/
```
Some OS X users may experience problems using the pre-built binaries in which case [Homebrew](https://brew.sh) might be a better option:
``` ```
brew install cfssl curl -L https://dl.step.sm/gh-release/cli/gh-release-header/v0.18.0/step_darwin_0.18.0_arm64.tar.gz | tar xz
sudo mv step_0.18.0/bin/step /usr/local/bin/
```
Or, if you'd like to use [Homebrew](https://brew.sh):
```
brew install step
``` ```
### Linux ### Linux
``` ```
wget -q --show-progress --https-only --timestamping \ curl -L https://dl.step.sm/gh-release/cli/gh-release-header/v0.18.0/step_linux_0.18.0_amd64.tar.gz
https://storage.googleapis.com/kubernetes-the-hard-way/cfssl/1.4.1/linux/cfssl \ sudo mv step_0.18.0/bin/step /usr/local/bin/
https://storage.googleapis.com/kubernetes-the-hard-way/cfssl/1.4.1/linux/cfssljson
```
```
chmod +x cfssl cfssljson
```
```
sudo mv cfssl cfssljson /usr/local/bin/
``` ```
### Verification ### Verification
Verify `cfssl` and `cfssljson` version 1.4.1 or higher is installed: Verify `step` version 0.18.0 or higher is installed:
``` ```
cfssl version step version
``` ```
> output > output
``` ```
Version: 1.4.1 Smallstep CLI/0.18.0 (linux/amd64)
Runtime: go1.12.12 Release Date: 2021-11-17 21:15 UTC
```
```
cfssljson --version
```
```
Version: 1.4.1
Runtime: go1.12.12
``` ```
## Install kubectl ## Install kubectl

348
docs/04-certificate-authority.md
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@ -1,100 +1,280 @@
# Provisioning a CA and Generating TLS Certificates # Provisioning a CA
In this lab you will provision a [PKI Infrastructure](https://en.wikipedia.org/wiki/Public_key_infrastructure) using CloudFlare's PKI toolkit, [cfssl](https://github.com/cloudflare/cfssl), then use it to bootstrap a Certificate Authority, and generate TLS certificates for the following components: etcd, kube-apiserver, kube-controller-manager, kube-scheduler, kubelet, and kube-proxy. In this lab you will provision a [PKI Infrastructure](https://en.wikipedia.org/wiki/Public_key_infrastructure) using Smallstep's CA server, [`step-ca`](https://github.com/smallstep/certificates), and generate TLS certificates for the following components: etcd, kube-apiserver, kube-controller-manager, kube-scheduler, kubelet, and kube-proxy.
## Certificate Authority ## Certificate Authority
In this section you will provision a Certificate Authority that can be used to generate additional TLS certificates. In this section you will provision a `step-ca` Certificate Authority that can be used to generate additional TLS certificates. The CA will only run on `controller-0`. While it's possible to run a high-availability CA across multiple nodes, it's not necessary in a small-to-medium sized Kubernetes cluster. The CA service would have to be down for several days before having any negative impact on the cluster.
Generate the CA configuration file, certificate, and private key: Connect to `controller-0`:
```
gcloud compute ssh controller-0
```
Download the `step` client and `step-ca` server binaries, and the `jq` command:
``` ```
{ {
wget -q --show-progress --https-only --timestamping \
"https://dl.step.sm/gh-release/certificates/gh-release-header/v0.18.0/step-ca_linux_0.18.0_amd64.tar.gz"
wget -q --show-progress --https-only --timestamping \
"https://dl.step.sm/gh-release/cli/gh-release-header/v0.18.0/step_linux_0.18.0_amd64.tar.gz"
sudo apt update
sudo apt install -y jq
}
```
cat > ca-config.json <<EOF Install the binaries:
```
{ {
"signing": { tar -xvf step-ca_linux_0.18.0_amd64.tar.gz
"default": { sudo mv step-ca_0.18.0/bin/* /usr/local/bin/
"expiry": "8760h" tar -xvf step_linux_0.18.0_amd64.tar.gz
}, sudo mv step_0.18.0/bin/* /usr/local/bin/
"profiles": {
"kubernetes": {
"usages": ["signing", "key encipherment", "server auth", "client auth"],
"expiry": "8760h"
} }
```
Now create a `step` user and the paths for `step-ca`:
```
{
sudo useradd --system --home /etc/step-ca --shell /bin/false step
} }
```
Create a CA configuration folder and generate passwords for the CA root key and the CA provisioner:
```
{
export STEPPATH=/etc/step-ca
umask 077
sudo mkdir -p $(step path)/db
< /dev/urandom tr -dc A-Za-z0-9 | head -c40 | sudo tee $(step path)/password > /dev/null
< /dev/urandom tr -dc A-Za-z0-9 | head -c40 > provisioner-password
umask 002
} }
```
Initialize your PKI:
```
{
INTERNAL_IP=$(curl -s -H "Metadata-Flavor: Google" \
http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/ip)
EXTERNAL_IP=$(curl -s -H "Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/access-configs/0/external-ip)
INTERNAL_HOSTNAME=$(hostname -f)
sudo -E step ca init --name="admin" \
--dns="$INTERNAL_IP,$INTERNAL_HOSTNAME,$EXTERNAL_IP" \
--address=":4443" --provisioner="kubernetes" \
--password-file="$(step path)/password" \
--provisioner-password-file="provisioner-password"
sudo -E step ca provisioner add acme --type ACME
} }
```
Configure the CA provisioner to issue 90-day certificates:
```
{
sudo jq '(.authority.provisioners[]) += {
"claims": {
"maxTLSCertDuration": "2160h",
"defaultTLSCertDuration": "2160h"
}
}' /etc/step-ca/config/ca.json > ca-new.json
sudo mv ca-new.json /etc/step-ca/config/ca.json
}
```
Put the CA configuration into place, and add the CA to systemd:
```
{
sudo chown -R step:step /etc/step-ca
cat <<EOF | sudo tee /etc/systemd/system/step-ca.service
[Unit]
Description=step-ca service
Documentation=https://smallstep.com/docs/step-ca
Documentation=https://smallstep.com/docs/step-ca/certificate-authority-server-production
After=network-online.target
Wants=network-online.target
StartLimitIntervalSec=30
StartLimitBurst=3
ConditionFileNotEmpty=/etc/step-ca/config/ca.json
ConditionFileNotEmpty=/etc/step-ca/password
[Service]
Type=simple
User=step
Group=step
Environment=STEPPATH=/etc/step-ca
WorkingDirectory=/etc/step-ca
ExecStart=/usr/local/bin/step-ca config/ca.json --password-file password
ExecReload=/bin/kill --signal HUP $MAINPID
Restart=on-failure
RestartSec=5
TimeoutStopSec=30
StartLimitInterval=30
StartLimitBurst=3
; Process capabilities & privileges
AmbientCapabilities=CAP_NET_BIND_SERVICE
CapabilityBoundingSet=CAP_NET_BIND_SERVICE
SecureBits=keep-caps
NoNewPrivileges=yes
; Sandboxing
ProtectSystem=full
ProtectHome=true
RestrictNamespaces=true
RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
PrivateTmp=true
ProtectClock=true
ProtectControlGroups=true
ProtectKernelTunables=true
ProtectKernelLogs=true
ProtectKernelModules=true
LockPersonality=true
RestrictSUIDSGID=true
RemoveIPC=true
RestrictRealtime=true
PrivateDevices=true
SystemCallFilter=@system-service
SystemCallArchitectures=native
MemoryDenyWriteExecute=true
ReadWriteDirectories=/etc/step-ca/db
[Install]
WantedBy=multi-user.target
EOF EOF
cat > ca-csr.json <<EOF
{
"CN": "Kubernetes",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "US",
"L": "Portland",
"O": "Kubernetes",
"OU": "CA",
"ST": "Oregon"
}
]
}
EOF
cfssl gencert -initca ca-csr.json | cfssljson -bare ca
} }
``` ```
Results: Save the root CA certificate:
```
sudo cat /etc/step-ca/certs/root_ca.crt | tee ca.pem > /dev/null
```
Finally, start the CA service:
```
{
sudo systemctl daemon-reload
sudo systemctl enable --now step-ca
}
```
## Verification
Check the CA health, then request and save the CA root certificate:
```
sudo -u step -E step ca health
```
Output:
```
ok
```
You can now sign out of `controller-0`.
# Generating certificates
## Bootstrapping with the CA
### Bootstrapping your local machine
Run the following on your local machine.
Download your CA's root certificate:
```
gcloud compute scp controller-0:ca.pem controller-0:provisioner-password .
```
Result:
``` ```
ca-key.pem
ca.pem ca.pem
provisioner-password
``` ```
Now bootstrap with your CA:
```
{
CA_IP=$(gcloud compute instances describe controller-0 \
--format='get(networkInterfaces[0].accessConfigs[0].natIP)')
step ca bootstrap --ca-url "https://$CA_IP:4443/" --fingerprint $(step certificate fingerprint ca.pem)
}
```
Output:
```
The root certificate has been saved in /home/carl/.step/authorities/XX.XXX.XXX.XXX/certs/root_ca.crt.
The authority configuration has been saved in /home/carl/.step/authorities/XX.XXX.XXX.XXX/config/defaults.json.
The profile configuration has been saved in /home/carl/.step/profiles/XX.XXX.XXX.XXX/config/defaults.json.
```
Add your CA URL and fingerprint to the project metadata on GCP, so instances can bootstrap:
```
gcloud compute project-info add-metadata --metadata="STEP_CA_URL=https://10.240.0.10:4443,STEP_CA_FINGERPRINT=$(step certificate fingerprint ca.pem)"
```
Output:
```
Updated [https://www.googleapis.com/compute/v1/projects/project-id-xxxxxx].
```
### Bootstrapping remote instances
Run each command on every node:
```
{
for i in 0 1 2; do
gcloud compute ssh worker-${i} -- \
step ca bootstrap \
--ca-url "$(curl -s -H "Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/project/attributes/STEP_CA_URL)" \
--fingerprint "$(curl -s -H "Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/project/attributes/STEP_CA_FINGERPRINT)"
gcloud compute ssh worker-${i} -- \
step ca bootstrap \
--ca-url "$(curl -s -H "Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/project/attributes/STEP_CA_URL)" \
--fingerprint "$(curl -s -H "Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/project/attributes/STEP_CA_FINGERPRINT)"
done
}
```
Output:
```
The root certificate has been saved in /home/carl/.step/certs/root_ca.crt.
The authority configuration has been saved in /home/carl/.step/config/defaults.json.
```
## Client and Server Certificates ## Client and Server Certificates
In this section you will generate client and server certificates for each Kubernetes component and a client certificate for the Kubernetes `admin` user. In this section you will generate client and server certificates for each Kubernetes component and a client certificate for the Kubernetes `admin` user.
### The Admin Client Certificate ### The Admin Client Certificate
Generate the `admin` client certificate and private key: On your local machine, generate the `admin` client certificate and private key:
``` ```
{ {
step ca certificate admin admin.pem admin-key.pem \
cat > admin-csr.json <<EOF --provisioner="kubernetes" \
{ --provisioner-password-file="provisioner-password"
"CN": "admin",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "US",
"L": "Portland",
"O": "system:masters",
"OU": "Kubernetes The Hard Way",
"ST": "Oregon"
}
]
}
EOF
cfssl gencert \
-ca=ca.pem \
-ca-key=ca-key.pem \
-config=ca-config.json \
-profile=kubernetes \
admin-csr.json | cfssljson -bare admin
} }
``` ```
@ -113,24 +293,6 @@ Generate a certificate and private key for each Kubernetes worker node:
``` ```
for instance in worker-0 worker-1 worker-2; do for instance in worker-0 worker-1 worker-2; do
cat > ${instance}-csr.json <<EOF
{
"CN": "system:node:${instance}",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "US",
"L": "Portland",
"O": "system:nodes",
"OU": "Kubernetes The Hard Way",
"ST": "Oregon"
}
]
}
EOF
EXTERNAL_IP=$(gcloud compute instances describe ${instance} \ EXTERNAL_IP=$(gcloud compute instances describe ${instance} \
--format 'value(networkInterfaces[0].accessConfigs[0].natIP)') --format 'value(networkInterfaces[0].accessConfigs[0].natIP)')
@ -138,13 +300,7 @@ EXTERNAL_IP=$(gcloud compute instances describe ${instance} \
INTERNAL_IP=$(gcloud compute instances describe ${instance} \ INTERNAL_IP=$(gcloud compute instances describe ${instance} \
--format 'value(networkInterfaces[0].networkIP)') --format 'value(networkInterfaces[0].networkIP)')
cfssl gencert \ step ca certificate "system:node:${instance}" ${instance}.pem ${instance}-key.pem --san "${instance}" --san "${EXTERNAL_IP}" --san "${INTERNAL_IP}" --provisioner "kubernetes" --provisioner-password-file "provisioner-password"
-ca=ca.pem \
-ca-key=ca-key.pem \
-config=ca-config.json \
-hostname=${instance},${EXTERNAL_IP},${INTERNAL_IP} \
-profile=kubernetes \
${instance}-csr.json | cfssljson -bare ${instance}
done done
``` ```
@ -159,6 +315,18 @@ worker-2-key.pem
worker-2.pem worker-2.pem
``` ```
### The Controller Manager Client Certificate ### The Controller Manager Client Certificate
Generate the `kube-controller-manager` client certificate and private key: Generate the `kube-controller-manager` client certificate and private key: