homelab/k8s/apps/amnezia/configmap-scripts.yaml

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: amneziawg-scripts
data:
  firewall-up.sh: |
    #!/usr/bin/env bash
    set -euo pipefail

    PORT="${1:-5847}"
    VPN_CIDR="${2:-10.8.0.0/16}"

    external_interface() {
      ip route get 1.1.1.1 | awk '{for (i=1;i<=NF;i++) if ($i=="dev") {print $(i+1); exit}}'
    }

    ensure_insert_rule() {
      local table_args=()
      if [ "${1:-}" = "-t" ]; then
        table_args=("$1" "$2")
        shift 2
      fi

      local chain="$1"
      shift

      if ! iptables "${table_args[@]}" -C "${chain}" "$@" >/dev/null 2>&1; then
        iptables "${table_args[@]}" -I "${chain}" 1 "$@"
      fi
    }

    delete_rule() {
      local table_args=()
      if [ "${1:-}" = "-t" ]; then
        table_args=("$1" "$2")
        shift 2
      fi

      local chain="$1"
      shift

      while iptables "${table_args[@]}" -D "${chain}" "$@" >/dev/null 2>&1; do
        true
      done
    }

    ensure_append_rule() {
      local table_args=()
      if [ "${1:-}" = "-t" ]; then
        table_args=("$1" "$2")
        shift 2
      fi

      local chain="$1"
      shift

      if ! iptables "${table_args[@]}" -C "${chain}" "$@" >/dev/null 2>&1; then
        iptables "${table_args[@]}" -A "${chain}" "$@"
      fi
    }

    EXT_IF="$(external_interface || true)"
    if [ -z "${EXT_IF}" ]; then
      EXT_IF="$(ip route show default | awk '{print $5; exit}')"
    fi
    if [ -z "${EXT_IF}" ]; then
      echo "Unable to detect external interface"
      exit 1
    fi

    sysctl -w net.ipv4.ip_forward=1

    delete_rule INPUT -i tailscale0 -p udp -m comment --comment amneziawg-block-tailscale -j DROP
    ensure_insert_rule INPUT -i "${EXT_IF}" -p udp --dport "${PORT}" -m comment --comment amneziawg-allow-external -j ACCEPT
    ensure_insert_rule INPUT -i tailscale0 -p udp --dport "${PORT}" -m comment --comment amneziawg-block-tailscale -j DROP
    ensure_append_rule INPUT -i awg0 -m comment --comment amneziawg-awg-input -j ACCEPT
    ensure_append_rule FORWARD -i awg0 -m comment --comment amneziawg-forward-in -j ACCEPT
    ensure_append_rule FORWARD -o awg0 -m comment --comment amneziawg-forward-out -j ACCEPT
    ensure_append_rule -t nat POSTROUTING -s "${VPN_CIDR}" -o "${EXT_IF}" -m comment --comment amneziawg-masquerade -j MASQUERADE

  firewall-down.sh: |
    #!/usr/bin/env bash
    set -euo pipefail

    PORT="${1:-5847}"
    VPN_CIDR="${2:-10.8.0.0/16}"

    external_interface() {
      ip route get 1.1.1.1 | awk '{for (i=1;i<=NF;i++) if ($i=="dev") {print $(i+1); exit}}'
    }

    delete_rule() {
      local table_args=()
      if [ "${1:-}" = "-t" ]; then
        table_args=("$1" "$2")
        shift 2
      fi

      local chain="$1"
      shift

      while iptables "${table_args[@]}" -D "${chain}" "$@" >/dev/null 2>&1; do
        true
      done
    }

    EXT_IF="$(external_interface || true)"
    if [ -z "${EXT_IF}" ]; then
      EXT_IF="$(ip route show default | awk '{print $5; exit}')"
    fi

    if [ -n "${EXT_IF}" ]; then
      delete_rule INPUT -i "${EXT_IF}" -p udp --dport "${PORT}" -m comment --comment amneziawg-allow-external -j ACCEPT
      delete_rule -t nat POSTROUTING -s "${VPN_CIDR}" -o "${EXT_IF}" -m comment --comment amneziawg-masquerade -j MASQUERADE
    fi

    delete_rule INPUT -i tailscale0 -p udp --dport "${PORT}" -m comment --comment amneziawg-block-tailscale -j DROP
    delete_rule INPUT -i tailscale0 -p udp -m comment --comment amneziawg-block-tailscale -j DROP
    delete_rule INPUT -i awg0 -m comment --comment amneziawg-awg-input -j ACCEPT
    delete_rule FORWARD -i awg0 -m comment --comment amneziawg-forward-in -j ACCEPT
    delete_rule FORWARD -o awg0 -m comment --comment amneziawg-forward-out -j ACCEPT

  run.sh: |
    #!/usr/bin/env bash
    set -euo pipefail

    SERVER_CONFIG="/etc/amnezia/server/awg0.conf"
    CLIENTS_DIR="${AMNEZIAWG_CLIENTS_DIR:-/run/amnezia/clients}"
    RUNTIME_CONFIG="/run/amnezia/awg0.conf"
    SYNC_CONFIG="/run/amnezia/awg0.sync.conf"
    STATUS_FILE="/run/amnezia/reload-status"
    RELOAD_INTERVAL="${AMNEZIAWG_RELOAD_INTERVAL:-10}"

    cleanup() {
      if awg show awg0 >/dev/null 2>&1; then
        awg-quick down "${RUNTIME_CONFIG}" || ip link delete awg0 || true
      fi
    }

    render_config() {
      mkdir -p "$(dirname "${RUNTIME_CONFIG}")"
      local tmp_config="${RUNTIME_CONFIG}.tmp"
      cp "${SERVER_CONFIG}" "${tmp_config}"
      chmod 0600 "${tmp_config}"

      local clients_found=0
      for client_config in "${CLIENTS_DIR}"/*; do
        [ -f "${client_config}" ] || continue
        [ -s "${client_config}" ] || continue
        printf '\n' >> "${tmp_config}"
        cat "${client_config}" >> "${tmp_config}"
        clients_found=1
      done

      if [ "${clients_found}" = "0" ]; then
        echo "No client peer configs found in ${CLIENTS_DIR}; starting without peers"
      fi

      mv "${tmp_config}" "${RUNTIME_CONFIG}"
      chmod 0600 "${RUNTIME_CONFIG}"
    }

    client_config_hash() {
      {
        for client_config in "${CLIENTS_DIR}"/*; do
          [ -f "${client_config}" ] || continue
          sha256sum "${client_config}"
        done
      } | sha256sum | awk '{print $1}'
    }

    write_reload_status() {
      local state="${1}"
      local hash="${2:-}"
      local applied_at_ms=""
      if [ "${state}" = "applied" ]; then
        applied_at_ms="$(($(date +%s) * 1000))"
      fi

      mkdir -p "$(dirname "${STATUS_FILE}")"
      {
        printf 'state=%s\n' "${state}"
        printf 'hash=%s\n' "${hash}"
        printf 'applied_at_ms=%s\n' "${applied_at_ms}"
      } > "${STATUS_FILE}.tmp"
      mv "${STATUS_FILE}.tmp" "${STATUS_FILE}"
    }

    apply_live_config() {
      render_config
      awg-quick strip "${RUNTIME_CONFIG}" > "${SYNC_CONFIG}"
      chmod 0600 "${SYNC_CONFIG}"
      awg syncconf awg0 "${SYNC_CONFIG}"
    }

    watch_client_config() {
      local last_hash="${1}"
      while true; do
        sleep "${RELOAD_INTERVAL}" &
        wait "$!" || return 0

        local current_hash
        current_hash="$(client_config_hash)"
        if [ "${current_hash}" = "${last_hash}" ]; then
          continue
        fi

        echo "Detected AmneziaWG client peer config change; applying with awg syncconf"
        if apply_live_config; then
          last_hash="${current_hash}"
          write_reload_status applied "${current_hash}"
          awg show awg0 || true
        else
          echo "ERROR: failed to hot-reload AmneziaWG client peer config" >&2
          write_reload_status error "${current_hash}"
        fi
      done
    }

    trap cleanup EXIT
    trap 'exit 0' TERM INT

    initial_hash="$(client_config_hash)"
    render_config
    cleanup
    awg-quick up "${RUNTIME_CONFIG}"
    awg show awg0 || true
    write_reload_status applied "${initial_hash}"
    watch_client_config "${initial_hash}"

  client-secret-sync.sh: |
    #!/usr/bin/env bash
    set -euo pipefail

    CLIENT_SECRET="${AMNEZIAWG_CLIENT_SECRET:-amneziawg-clients}"
    CLIENT_SECRET_KEY="${AMNEZIAWG_CLIENT_SECRET_KEY:-peers.conf}"
    CLIENTS_DIR="${AMNEZIAWG_CLIENTS_DIR:-/run/amnezia/clients}"
    PEERS_FILE="${CLIENTS_DIR}/peers.conf"
    SYNC_INTERVAL="${AMNEZIAWG_CLIENT_SECRET_SYNC_INTERVAL:-5}"
    NAMESPACE="${POD_NAMESPACE:-$(cat /var/run/secrets/kubernetes.io/serviceaccount/namespace)}"

    write_empty_once() {
      mkdir -p "${CLIENTS_DIR}"
      if [ ! -f "${PEERS_FILE}" ]; then
        : > "${PEERS_FILE}"
        chmod 0600 "${PEERS_FILE}"
      fi
    }

    sync_once() {
      mkdir -p "${CLIENTS_DIR}"
      local tmp_file="${PEERS_FILE}.tmp"
      local encoded=""

      if ! encoded="$(kubectl get secret "${CLIENT_SECRET}" -n "${NAMESPACE}" -o "go-template={{ index .data \"${CLIENT_SECRET_KEY}\" }}" 2>/dev/null)"; then
        echo "WARN: failed to read Secret ${NAMESPACE}/${CLIENT_SECRET}; keeping current peers" >&2
        write_empty_once
        return 0
      fi

      if [ -n "${encoded}" ]; then
        printf '%s' "${encoded}" | base64 -d > "${tmp_file}"
      else
        : > "${tmp_file}"
      fi
      chmod 0600 "${tmp_file}"

      if [ -f "${PEERS_FILE}" ] && cmp -s "${tmp_file}" "${PEERS_FILE}"; then
        rm -f "${tmp_file}"
        return 0
      fi

      mv "${tmp_file}" "${PEERS_FILE}"
      echo "Synced AmneziaWG client peers from Secret ${NAMESPACE}/${CLIENT_SECRET}:${CLIENT_SECRET_KEY}"
    }

    if [ "${1:-}" = "once" ]; then
      sync_once
      exit 0
    fi

    while true; do
      sync_once || true
      sleep "${SYNC_INTERVAL}"
    done

  status-patch.sh: |
    #!/usr/bin/env bash
    set -euo pipefail

    STATUS_FILE="/run/amnezia/reload-status"
    PATCH_INTERVAL="${AMNEZIAWG_STATUS_PATCH_INTERVAL:-5}"
    NAMESPACE="${POD_NAMESPACE:-$(cat /var/run/secrets/kubernetes.io/serviceaccount/namespace)}"
    : "${POD_NAME:?POD_NAME is required}"

    last_file_hash=""

    patch_status() {
      local state="unknown"
      local hash=""
      local applied_at_ms=""

      # The file is generated by run.sh and contains only shell assignments.
      # shellcheck disable=SC1090
      source "${STATUS_FILE}"

      kubectl patch pod "${POD_NAME}" -n "${NAMESPACE}" --type merge -p "{\"metadata\":{\"annotations\":{\"amnezia-fellow.hexor.cy/client-secret-reload-status\":\"${state}\",\"amnezia-fellow.hexor.cy/client-secret-applied-at-ms\":\"${applied_at_ms}\",\"amnezia-fellow.hexor.cy/client-secret-applied-hash\":\"${hash}\"}}}"
    }

    while true; do
      if [ -f "${STATUS_FILE}" ]; then
        file_hash="$(sha256sum "${STATUS_FILE}" | awk '{print $1}')"
        if [ "${file_hash}" != "${last_file_hash}" ]; then
          patch_status || true
          last_file_hash="${file_hash}"
        fi
      fi
      sleep "${PATCH_INTERVAL}"
    done