Add Cloudflare DDNS updater scripts and systemd configurations

dyndns/cf-ddns.sh

@@ -0,0 +1,76 @@
+#!/usr/bin/env bash
+# cf-ddns.sh - Cloudflare DDNS updater
+set -euo pipefail
+
+DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+if [ -f "${DIR}/.env" ]; then
+  # shellcheck disable=SC1091
+  source "${DIR}/.env"
+else
+  echo "$(date -Iseconds) ERROR: missing ${DIR}/.env (create from .env.example)" >&2
+  exit 1
+fi
+
+: "${CF_API_TOKEN:?need CF_API_TOKEN in .env}"
+: "${ZONE:?need ZONE in .env}"
+: "${RECORDS:?need RECORDS in .env}"
+: "${IP_URL:=https://ipv4.icanhazip.com}"
+: "${PROXIED:=false}"
+
+AUTH_HEADER="Authorization: Bearer ${CF_API_TOKEN}"
+CT_HEADER="Content-Type: application/json"
+
+log() { echo "$(date -Iseconds) $*"; }
+
+IP=$(curl -fsS "${IP_URL}" | tr -d '[:space:]')
+if [[ -z "${IP}" ]]; then
+  log "ERROR: could not determine public IP"
+  exit 1
+fi
+
+ZONE_ID=$(curl -fsS -X GET "https://api.cloudflare.com/client/v4/zones?name=${ZONE}" \
+  -H "${AUTH_HEADER}" -H "${CT_HEADER}" | jq -r '.result[0].id // empty')
+
+if [[ -z "${ZONE_ID}" ]]; then
+  log "ERROR: zone not found: ${ZONE}"
+  exit 1
+fi
+
+IFS=',' read -r -a RECORD_ARR <<< "${RECORDS}"
+for fullrec in "${RECORD_ARR[@]}"; do
+  rec=$(echo "${fullrec}" | xargs)
+  log "Processing ${rec}"
+  info=$(curl -fsS -X GET "https://api.cloudflare.com/client/v4/zones/${ZONE_ID}/dns_records?name=${rec}&type=A" \
+    -H "${AUTH_HEADER}" -H "${CT_HEADER}")
+
+  RECORD_ID=$(echo "$info" | jq -r '.result[0].id // empty')
+  CURRENT_CONTENT=$(echo "$info" | jq -r '.result[0].content // empty')
+
+  if [[ -z "${RECORD_ID}" ]]; then
+    log "Creating ${rec} -> ${IP}"
+    create_resp=$(curl -fsS -X POST "https://api.cloudflare.com/client/v4/zones/${ZONE_ID}/dns_records" \
+      -H "${AUTH_HEADER}" -H "${CT_HEADER}" \
+      --data "{\"type\":\"A\",\"name\":\"${rec}\",\"content\":\"${IP}\",\"ttl\":1,\"proxied\":${PROXIED}}")
+    ok=$(echo "$create_resp" | jq -r '.success // false')
+    if [[ "$ok" != "true" ]]; then
+      log "ERROR creating ${rec}: ${create_resp}"
+    else
+      log "Created ${rec}"
+    fi
+  else
+    if [[ "${CURRENT_CONTENT}" == "${IP}" ]]; then
+      log "${rec} unchanged (${IP})"
+    else
+      log "Updating ${rec} -> ${IP}"
+      upd_resp=$(curl -fsS -X PUT "https://api.cloudflare.com/client/v4/zones/${ZONE_ID}/dns_records/${RECORD_ID}" \
+        -H "${AUTH_HEADER}" -H "${CT_HEADER}" \
+        --data "{\"type\":\"A\",\"name\":\"${rec}\",\"content\":\"${IP}\",\"ttl\":1,\"proxied\":${PROXIED}}")
+      ok=$(echo "$upd_resp" | jq -r '.success // false')
+      if [[ "$ok" != "true" ]]; then
+        log "ERROR updating ${rec}: ${upd_resp}"
+      else
+        log "Updated ${rec}"
+      fi
+    fi
+  fi
+done