diff --git a/server.py b/server.py index ace5220..0ff6f73 100644 --- a/server.py +++ b/server.py @@ -11,6 +11,20 @@ from sanic.exceptions import InvalidUsage app = Sanic() +async def query_dns(host, dns_entry_type): + loop = asyncio.get_event_loop() + dns_resolver = aiodns.DNSResolver(loop=loop) + + try: + return await dns_resolver.query(host, dns_entry_type) + except aiodns.error.DNSError: + return [] + except Exception: + import traceback + traceback.print_exc() + logger.error("Unhandled error while resolving DNS entry") + + @app.route("/check/", methods=["POST"]) async def check_http(request): ip = request.ip @@ -44,26 +58,50 @@ async def check_http(request): }) # TODO handle ipv6 - loop = asyncio.get_event_loop() - dns_resolver = aiodns.DNSResolver(loop=loop) - dns_entry = await dns_resolver.query(domain, 'A') + # ipv6 situation + if ":" in ip: + dns_entry = await query_dns(domain, "AAAA") - if not dns_entry: - logger.info(f"Invalid request, not A DNS entry for domain {domain})") - return json_response({ - "status": "error", - "code": "error_no_dns_entry_for_domain", - "content": "there is not A (ipv4) DNS entry for domain {domain}", - }) + if not dns_entry: + # check if entry in ip4 for custom error + dns_entry = await query_dns(domain, "A") + + # there is an ipv4 entry but the request is made in ipv6, ask to uses ipv4 instead + if dns_entry: + logger.info(f"[ipv6] Invalid request, no AAAA DNS entry for domain {domain} BUT ipv4 entry, ask user to request in ipv4") + return json_response({ + "status": "error", + "code": "error_no_ipv6_dns_entry_but_ipv4_dns_entry", + "content": f"there is not AAAA (ipv6) DNS entry for domain {domain} BUT there is an entry in ipv4, please redo the request in ipv4", + }) + + else: + logger.info(f"[ipv6] Invalid request, no DNS entry for domain {domain} (both in ipv6 and ip4)") + return json_response({ + "status": "error", + "code": "error_no_ipv4_ipv6_dns_entry_for_domain", + "content": f"there is not A (ipv4) and AAAA (ipv6) DNS entry for domain {domain}", + }) + # ipv4 situation + else: + dns_entry = await query_dns(domain, "A") + + if not dns_entry: + logger.info(f"[ipv4] Invalid request, no DNS entry for domain {domain}") + return json_response({ + "status": "error", + "code": "error_no_ipv4_dns_entry_for_domain", + "content": f"there is not A (ipv4) and AAAA (ipv6) DNS entry for domain {domain}", + }) dns_entry = dns_entry[0] if dns_entry.host != ip: - logger.info(f"Invalid request, not A DNS entry for domain {domain})") + logger.info(f"Invalid request, A DNS entry {dns_entry.host} for domain {domain} doesn't match request ip {ip}") return json_response({ "status": "error", "code": "error_dns_entry_doesnt_match_request_ip", - "content": "error, the request is made from the ip {ip} but the dns entry said {domain} has the ip {dns_entry.host}, you can only check a domain configured for your ip", + "content": f"error, the request is made from the ip {ip} but the dns entry said {domain} has the ip {dns_entry.host}, you can only check a domain configured for your ip", }) async with aiohttp.ClientSession() as session: @@ -96,7 +134,7 @@ async def check_http(request): # [x] - validate domain is in correct format # [x] - check dns that domain == ip # [x] - if not, complain - # [ ] - handle ipv6 + # [x] - handle ipv6 # [x] - if everything is ok, try to get with http # [x] - ADD TIMEOUT # [x] - try/catch, if everything is ok → response ok