homelab/active/kubernetes_userspace/scripts/upsertuser.sh

#!/bin/bash

# Use
# ./upsert.sh <ssh_address> <server_fqdn (for kubectl)> <user>
# Note, do not specify https:// or :port for the fqdn, just give the domain
# Port is expected to be 6443. You can change this later in the generated conf 
# ./upsert.sh node1 containers.reeseapps.com testuser
# ./upsert.sh 192.168.1.10 mydomain.ddns.net admin

export SERVER=$1
export FQDN=$2
export KUBE_USER=$3

export CERT_DIR=$HOME/.kube/$FQDN/users/$KUBE_USER
export CA_CERT_DIR=$HOME/.kube/$FQDN

export SERVER_USER_DIR="~/.kube/users/$KUBE_USER"
export SERVER_NAME=$(echo "$FQDN" | sed 's/\./-/g')
export SERVER_USER="$KUBE_USER-$SERVER_NAME"

export KUBECONFIG="$HOME/.kube/$KUBE_USER-config"

if [ -z $KUBE_USER ]; then
echo "No arguments supplied! Format is ./upsert.sh <SERVER_FQDN> <USER>"
exit 1
fi

if [ -z $SERVER ]; then
echo "No server supplied for user $KUBE_USER"
exit 1   
fi

if [ $KUBE_USER = "admin" ]; then
echo "Creating admin user for server $SERVER"
fi

echo "Creating cert dir"
mkdir -p $CERT_DIR

if [ $? -ne 0 ]; then
    echo "Couldn't create cert dir at $CERT_DIR"
    exit 1
fi

echo "Generating openssl cert"
podman run -it -v $CERT_DIR:/$KUBE_USER python:latest openssl genrsa -out /$KUBE_USER/$KUBE_USER.key 2048

if [ $KUBE_USER = "admin" ]; then
podman run -it -v $CERT_DIR:/$KUBE_USER python:latest openssl req -new -key /$KUBE_USER/$KUBE_USER.key -out /$KUBE_USER/$KUBE_USER.csr -subj "/CN=$KUBE_USER/O=system:masters"
else
podman run -it -v $CERT_DIR:/$KUBE_USER python:latest openssl req -new -key /$KUBE_USER/$KUBE_USER.key -out /$KUBE_USER/$KUBE_USER.csr -subj "/CN=$KUBE_USER/O=user"
fi
# /CN=admin/O=manager

if [ $? -ne 0 ]; then
    echo "Couldn't create cert with Podman. Are you sure it's running?"
    exit 1
fi

echo "Creating namespace dir on server"
ssh $SERVER "mkdir -p $SERVER_USER_DIR"
echo "Copying client csr to server cert dir"
scp $CERT_DIR/$KUBE_USER.csr $SERVER:$SERVER_USER_DIR/$KUBE_USER.csr

if [ $? -ne 0 ]; then
    echo "Failed to copy client csr to server cert dir"
    exit 1
fi

echo "Getting cert signing pod"
export CERT_POD=$(ssh $SERVER "kubectl get pod -n kube-system --selector=app=certsigner --output=jsonpath={.items..metadata.name}")

if [ -z $CERT_POD ]; then
    echo "Installing certsigner"
    helm template certsigner ./certsigner | ssh $SERVER "sudo -t -E kubectl apply -f -"
fi

while [ -z $CERT_POD ]; do
    echo "Getting cert signing pod"
    export CERT_POD=$(ssh $SERVER "kubectl get pod -n kube-system --selector=app=certsigner --output=jsonpath={.items..metadata.name}")
    sleep 2
done

if [ $? -ne 0 ]; then
echo "Failed to install certsigner."
exit 1
fi

echo "Signing cert with pod $CERT_POD"
ssh $SERVER "kubectl -n kube-system cp $SERVER_USER_DIR/$KUBE_USER.csr $CERT_POD:/certs/$KUBE_USER.csr"
ssh $SERVER "kubectl -n kube-system exec $CERT_POD -- openssl x509 -in /certs/$KUBE_USER.csr -req -CA /keys/client-ca.crt -CAkey /keys/client-ca.key -set_serial $(python -c 'import random; print(random.randint(1000000000, 9999999999))') -out /certs/$KUBE_USER.crt -days 5000"
ssh $SERVER "kubectl -n kube-system cp $CERT_POD:/certs/$KUBE_USER.crt ~/.kube/users/$KUBE_USER/$KUBE_USER.crt"
echo "retrieving signed cert"
scp $SERVER:$SERVER_USER_DIR/$KUBE_USER.crt $CERT_DIR/$KUBE_USER.crt

echo "retrieving server ca"
wget --no-check-certificate https://$FQDN:6443/cacerts -O $CA_CERT_DIR/server-ca.pem

echo "creating $FQDN-$KUBE_USER context"
kubectl config set-context $FQDN-$KUBE_USER

echo "setting $FQDN-$KUBE_USER as current context"
kubectl config set current-context $FQDN-$KUBE_USER

echo "adding server to config with new context $FQDN-$KUBE_USER"
kubectl config set-cluster $FQDN --server=https://$FQDN:6443 --certificate-authority=$CA_CERT_DIR/server-ca.pem
kubectl config set contexts.$(kubectl config current-context).cluster $FQDN

echo "adding user to config file"
kubectl config set-credentials $SERVER_USER --client-certificate=$CERT_DIR/$KUBE_USER.crt --client-key=$CERT_DIR/$KUBE_USER.key

echo "setting user context"
kubectl config set contexts.$(kubectl config current-context).user $SERVER_USER

if [ $KUBE_USER = "admin" ]; then
echo "Admin user created, skipping namespace"
echo "export KUBECONFIG=$KUBECONFIG"
exit 0
fi

echo "Templating namespace with helm and copying to server"
helm template $KUBE_USER --set user=$KUBE_USER ./userspace | ssh $SERVER "cat - > $SERVER_USER_DIR/namespace.yaml"

if [ $? -ne 0 ]; then
    echo "Failed to template namespace. Is helm installed?"
    exit 1
fi

echo "Creating namespace from template"
ssh $SERVER "kubectl apply -f $SERVER_USER_DIR/namespace.yaml"

echo "Setting namespace context"
kubectl config set contexts.$(kubectl config current-context).namespace $KUBE_USER

if [ $? -ne 0 ]; then
    echo "Failed to create namespace"
    exit 1
fi

echo "export KUBECONFIG=$KUBECONFIG"