add Flatcar k3d security test host

scripts/proxmox/create-flatcar-k3d-test-host.sh

@@ -0,0 +1,212 @@
+#!/usr/bin/env bash
+# Create a Flatcar VM for disposable Linux k3d security testing.
+# Run this on the Proxmox host as root.
+set -Eeuo pipefail
+
+usage() {
+  cat <<'EOF'
+Usage:
+  VM_ID=9101 \
+  SSH_PUBLIC_KEY="$(cat ~/.ssh/id_ed25519.pub)" \
+  ./create-flatcar-k3d-test-host.sh
+
+Required environment variables:
+  VM_ID                 Proxmox VM ID that does not already exist
+  SSH_PUBLIC_KEY        SSH public key for the Flatcar core user
+
+Optional environment variables:
+  VM_NAME               VM name, default flatcar-k3d-test
+  CORES                 CPU cores, default 4
+  MEMORY_MB             Memory in MiB, default 16384
+  DISK_SIZE             Final disk size, default 100G
+  BRIDGE                Proxmox bridge, default vmbr0
+  DISK_STORAGE          Storage for the VM disk, default local-lvm
+  CLOUDINIT_STORAGE     Storage for the Cloud-Init drive, default local-lvm
+  SNIPPET_STORAGE       Proxmox storage containing snippets, default local
+  SNIPPET_DIR           Host snippet directory, default /var/lib/vz/snippets
+  IMAGE_CACHE_DIR       Host image cache, default /var/lib/vz/template/cache
+  FLATCAR_IMAGE_URL     Flatcar Stable amd64 Proxmox image URL
+  FLATCAR_IMAGE_SHA256  Optional expected SHA256 for the image
+  K3D_VERSION           k3d version installed on first boot, default v5.9.0
+  KUBECTL_VERSION       kubectl version installed on first boot, default v1.35.5
+
+The VM uses DHCP and is intended to be a dedicated disposable Linux test host.
+It is not a Gitea runner and does not receive a registration token.
+EOF
+}
+
+die() {
+  echo "ERROR: $*" >&2
+  exit 1
+}
+
+require_command() {
+  command -v "$1" >/dev/null 2>&1 || die "required command not found: $1"
+}
+
+[[ "${1:-}" != "--help" && "${1:-}" != "-h" ]] || { usage; exit 0; }
+[[ "$(id -u)" -eq 0 ]] || die "run this script as root on the Proxmox host"
+
+for command_name in qm pvesm curl sha256sum jq; do
+  require_command "$command_name"
+done
+
+: "${VM_ID:?VM_ID is required}"
+: "${SSH_PUBLIC_KEY:?SSH_PUBLIC_KEY is required}"
+
+VM_NAME="${VM_NAME:-flatcar-k3d-test}"
+CORES="${CORES:-4}"
+MEMORY_MB="${MEMORY_MB:-16384}"
+DISK_SIZE="${DISK_SIZE:-100G}"
+BRIDGE="${BRIDGE:-vmbr0}"
+DISK_STORAGE="${DISK_STORAGE:-local-lvm}"
+CLOUDINIT_STORAGE="${CLOUDINIT_STORAGE:-local-lvm}"
+SNIPPET_STORAGE="${SNIPPET_STORAGE:-local}"
+SNIPPET_DIR="${SNIPPET_DIR:-/var/lib/vz/snippets}"
+IMAGE_CACHE_DIR="${IMAGE_CACHE_DIR:-/var/lib/vz/template/cache}"
+FLATCAR_IMAGE_URL="${FLATCAR_IMAGE_URL:-https://stable.release.flatcar-linux.net/amd64-usr/current/flatcar_production_proxmoxve_image.img}"
+K3D_VERSION="${K3D_VERSION:-v5.9.0}"
+KUBECTL_VERSION="${KUBECTL_VERSION:-v1.35.5}"
+
+[[ "$VM_ID" =~ ^[0-9]+$ ]] || die "VM_ID must be numeric"
+[[ "$CORES" =~ ^[0-9]+$ ]] || die "CORES must be numeric"
+[[ "$MEMORY_MB" =~ ^[0-9]+$ ]] || die "MEMORY_MB must be numeric"
+
+if qm status "$VM_ID" >/dev/null 2>&1; then
+  die "VM $VM_ID already exists; choose another VM_ID"
+fi
+
+snippet_storages="$(pvesm status --content snippets 2>/dev/null || true)"
+awk -v storage="$SNIPPET_STORAGE" '$1 == storage {found = 1} END {exit !found}' <<<"$snippet_storages" || die "storage $SNIPPET_STORAGE is not configured for snippets"
+
+mkdir -p "$SNIPPET_DIR" "$IMAGE_CACHE_DIR"
+chmod 0750 "$SNIPPET_DIR"
+
+work_dir="$(mktemp -d /tmp/flatcar-k3d.XXXXXX)"
+cleanup() { rm -rf "$work_dir"; }
+trap cleanup EXIT
+
+image_path="$IMAGE_CACHE_DIR/$(basename "$FLATCAR_IMAGE_URL")"
+snippet_name="flatcar-k3d-test-${VM_ID}-user-data"
+snippet_path="$SNIPPET_DIR/$snippet_name"
+
+if [[ -s "$image_path" ]]; then
+  echo "Using cached Flatcar image: $image_path"
+else
+  echo "Downloading Flatcar image: $FLATCAR_IMAGE_URL"
+  curl --fail --location --retry 3 --output "$image_path.partial" "$FLATCAR_IMAGE_URL"
+  mv "$image_path.partial" "$image_path"
+fi
+
+if [[ -n "${FLATCAR_IMAGE_SHA256:-}" ]]; then
+  printf '%s  %s\n' "$FLATCAR_IMAGE_SHA256" "$image_path" | sha256sum --check --strict -
+fi
+
+bootstrap="$work_dir/bootstrap-k3d-test-host.sh"
+cat >"$bootstrap" <<EOF
+#!/bin/bash
+set -Eeuo pipefail
+
+mkdir -p /opt/k3d-test/bin /opt/k3d-test/workspace
+chmod 0755 /opt/k3d-test /opt/k3d-test/bin /opt/k3d-test/workspace
+mkdir -p /home/core/bin
+chown core:core /opt/k3d-test/workspace
+
+curl --fail --location --retry 3 \\
+  --output /opt/k3d-test/bin/k3d \\
+  https://github.com/k3d-io/k3d/releases/download/${K3D_VERSION}/k3d-linux-amd64
+chmod 0755 /opt/k3d-test/bin/k3d
+
+curl --fail --location --retry 3 \\
+  --output /opt/k3d-test/bin/kubectl \\
+  https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/linux/amd64/kubectl
+chmod 0755 /opt/k3d-test/bin/kubectl
+
+ln -sfn /opt/k3d-test/bin/k3d /home/core/bin/k3d
+ln -sfn /opt/k3d-test/bin/kubectl /home/core/bin/kubectl
+cat >/home/core/.profile <<'PROFILE'
+export PATH="/home/core/bin:/opt/k3d-test/bin:$PATH"
+PROFILE
+chown -R core:core /home/core/bin /home/core/.profile
+touch /opt/k3d-test/.tools-installed
+EOF
+
+bootstrap_unit="$work_dir/k3d-test-tools.service"
+cat >"$bootstrap_unit" <<'EOF'
+[Unit]
+Description=Install k3d test host tooling
+After=network-online.target docker.service
+Wants=network-online.target
+Requires=docker.service
+ConditionPathExists=!/opt/k3d-test/.tools-installed
+
+[Service]
+Type=oneshot
+ExecStart=/opt/k3d-test/bootstrap-k3d-test-host.sh
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+jq -n \
+  --arg ssh_key "$SSH_PUBLIC_KEY" \
+  --rawfile bootstrap "$bootstrap" \
+  --rawfile bootstrap_unit "$bootstrap_unit" \
+  '{
+    ignition: {version: "3.3.0"},
+    storage: {
+      directories: [
+        {path: "/opt/k3d-test", mode: 493},
+        {path: "/opt/k3d-test/bin", mode: 493},
+        {path: "/opt/k3d-test/workspace", mode: 493}
+      ],
+      files: [
+        {path: "/opt/k3d-test/bootstrap-k3d-test-host.sh", mode: 365, contents: {source: ("data:text/plain;charset=utf-8," + ($bootstrap | @uri))}}
+      ]
+    },
+    systemd: {
+      units: [
+        {name: "docker.service", enabled: true},
+        {name: "k3d-test-tools.service", enabled: true, contents: $bootstrap_unit}
+      ]
+    },
+    passwd: {users: [{name: "core", sshAuthorizedKeys: [$ssh_key]}]}
+  }' >"$snippet_path"
+
+chmod 0600 "$snippet_path"
+
+echo "Creating Proxmox VM $VM_ID"
+qm create "$VM_ID" \
+  --name "$VM_NAME" \
+  --ostype l26 \
+  --cores "$CORES" \
+  --memory "$MEMORY_MB" \
+  --net0 "virtio,bridge=$BRIDGE" \
+  --ipconfig0 ip=dhcp \
+  --agent enabled=1 \
+  --onboot 1 \
+  --scsihw virtio-scsi-single
+
+qm disk import "$VM_ID" "$image_path" "$DISK_STORAGE"
+qm set "$VM_ID" --scsi0 "$DISK_STORAGE:vm-${VM_ID}-disk-0"
+qm resize "$VM_ID" scsi0 "$DISK_SIZE"
+qm set "$VM_ID" --boot order=scsi0
+qm set "$VM_ID" --ide2 "$CLOUDINIT_STORAGE:cloudinit"
+qm set "$VM_ID" --cicustom "user=${SNIPPET_STORAGE}:snippets/${snippet_name}"
+qm start "$VM_ID"
+
+cat <<EOF
+
+Flatcar k3d test host created.
+
+VM ID:   $VM_ID
+VM name: $VM_NAME
+Snippet: $snippet_path
+
+After DHCP assigns an address, verify:
+  ssh core@<vm-ip> 'systemctl status docker k3d-test-tools --no-pager'
+  ssh core@<vm-ip> 'k3d version && kubectl version --client'
+
+The test host has no Gitea token and is separate from the CI runner.
+EOF