Avoid fake IPv6 examples

karldns/web/components.py

@@ -143,14 +143,27 @@ def _example_update_ips(request_ip: str | None = None) -> tuple[str, str]:
 
 def _manual_update_commands(update_url: str, request_ip: str | None = None) -> str:
     update_base = update_url.split("?", 1)[0]
-    ipv4, ipv6 = _example_update_ips(request_ip)
-    return "\n".join(
-        [
-            f"curl -sS '{update_base}?myip={ipv4}'",
-            f"curl -sS '{update_base}?myipv6={ipv6}'",
-            f"curl -sS '{update_base}'  # use request IP",
-        ]
-    )
+    request_version, request_address = _known_request_ip(request_ip)
+    lines = []
+    if request_version in {None, 4}:
+        ipv4, _ = _example_update_ips(request_ip)
+        lines.append(f"curl -sS '{update_base}?myip={ipv4}'")
+    if request_version == 6:
+        lines.append(f"curl -sS '{update_base}?myipv6={request_address}'")
+    lines.append(f"curl -sS '{update_base}'  # use request IP")
+    return "\n".join(lines)
+
+
+def _known_request_ip(request_ip: str | None = None) -> tuple[int | None, str]:
+    if not request_ip:
+        return None, ""
+    try:
+        parsed = ip_address(request_ip.strip())
+    except ValueError:
+        return None, ""
+    if not parsed.is_global:
+        return None, ""
+    return parsed.version, str(parsed)
 
 
 def _manual_update_panel(commands: str) -> SafeHtml: