diff --git a/bin/tests/system/resend_loop/ans3/ans.py b/bin/tests/system/resend_loop/ans3/ans.py new file mode 100644 index 0000000000..90a3f2f9cc --- /dev/null +++ b/bin/tests/system/resend_loop/ans3/ans.py @@ -0,0 +1,128 @@ +# Copyright (C) Internet Systems Consortium, Inc. ("ISC") +# +# SPDX-License-Identifier: MPL-2.0 +# +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, you can obtain one at https://mozilla.org/MPL/2.0/. +# +# See the COPYRIGHT file distributed with this work for additional +# information regarding copyright ownership. + +from collections.abc import AsyncGenerator + +import dns.edns +import dns.name +import dns.rcode +import dns.rdatatype +import dns.rrset + +from isctest.asyncserver import ( + AsyncDnsServer, + DnsResponseSend, + QueryContext, + ResponseHandler, +) + + +def _get_cookie(qctx: QueryContext): + for o in qctx.query.options: + if o.otype == dns.edns.OptionType.COOKIE: + cookie = o + try: + if len(cookie.server) == 0: + cookie.server = b"\x11\x22\x33\x44\x55\x66\x77\x88" + except AttributeError: # dnspython<2.7.0 compat + if len(o.data) == 8: + cookie.data *= 2 + + return cookie + + return None + + +class PrimeHandler(ResponseHandler): + """ + Specifically handle priming query for "." NS (type 2) + """ + + def match(self, qctx: QueryContext) -> bool: + return len(qctx.qname.labels) == 0 and qctx.qtype == dns.rdatatype.NS + + async def get_responses( + self, qctx: QueryContext + ) -> AsyncGenerator[DnsResponseSend, None]: + + ns_rrset = dns.rrset.from_text( + ".", dns.rdatatype.NS, qctx.qclass, "a.root-servers.nil." + ) + a_rrset = dns.rrset.from_text( + "a.root-servers.nil.", dns.rdatatype.A, qctx.qclass, "10.53.0.3" + ) + + response = qctx.prepare_new_response(with_zone_data=False) + response.set_rcode(dns.rcode.NOERROR) + response.answer.append(ns_rrset) + response.additional.append(a_rrset) + + yield DnsResponseSend(response, authoritative=True) + + +class CookieHandler(ResponseHandler): + def match(self, qctx: QueryContext) -> bool: + example = dns.name.from_text("example") + return qctx.qname.is_subdomain(example) + + async def get_responses( + self, qctx: QueryContext + ) -> AsyncGenerator[DnsResponseSend, None]: + + qctx.prepare_new_response() + + # Check for client cookie + cookie = _get_cookie(qctx) + + # If missing cookie entirely, just return SERVFAIL + if cookie is None: + qctx.response.set_rcode(dns.rcode.SERVFAIL) + yield DnsResponseSend(qctx.response, authoritative=True) + + # If there is a client cookie, mock BADCOOKIE to trigger + # the resend loop logic. + qctx.response.use_edns(options=[cookie]) + qctx.response.set_rcode(dns.rcode.BADCOOKIE) + yield DnsResponseSend(qctx.response, authoritative=True) + + +class NoErrorHandler(ResponseHandler): + """ + If the query is NOT a subdomain of example, respond with standard NOERROR empty answer + """ + + async def get_responses( + self, qctx: QueryContext + ) -> AsyncGenerator[DnsResponseSend, None]: + + qctx.prepare_new_response() + qctx.response.set_rcode(dns.rcode.NOERROR) + yield DnsResponseSend(qctx.response, authoritative=True) + + +def resend_server() -> AsyncDnsServer: + server = AsyncDnsServer(default_aa=True, default_rcode=dns.rcode.NOERROR) + server.install_response_handlers( + [ + PrimeHandler(), + CookieHandler(), + NoErrorHandler(), + ] + ) + return server + + +def main() -> None: + resend_server().run() + + +if __name__ == "__main__": + main() diff --git a/bin/tests/system/resend_loop/ns4/named.conf.j2 b/bin/tests/system/resend_loop/ns4/named.conf.j2 new file mode 100644 index 0000000000..360bc12e17 --- /dev/null +++ b/bin/tests/system/resend_loop/ns4/named.conf.j2 @@ -0,0 +1,16 @@ +options { + query-source address 10.53.0.4; + notify-source 10.53.0.4; + transfer-source 10.53.0.4; + port @PORT@; + pid-file "named.pid"; + listen-on { 10.53.0.4; }; + listen-on-v6 { none; }; + recursion yes; + dnssec-validation no; +}; + +zone "." IN { + type hint; + file "root.hint"; +}; diff --git a/bin/tests/system/resend_loop/ns4/root.hint b/bin/tests/system/resend_loop/ns4/root.hint new file mode 100644 index 0000000000..3889a8b353 --- /dev/null +++ b/bin/tests/system/resend_loop/ns4/root.hint @@ -0,0 +1,14 @@ +; Copyright (C) Internet Systems Consortium, Inc. ("ISC") +; +; SPDX-License-Identifier: MPL-2.0 +; +; This Source Code Form is subject to the terms of the Mozilla Public +; License, v. 2.0. If a copy of the MPL was not distributed with this +; file, you can obtain one at https://mozilla.org/MPL/2.0/. +; +; See the COPYRIGHT file distributed with this work for additional +; information regarding copyright ownership. + +$TTL 999999 +. IN NS a.root-servers.nil. +a.root-servers.nil. IN A 10.53.0.3 diff --git a/bin/tests/system/resend_loop/tests_resend_loop.py b/bin/tests/system/resend_loop/tests_resend_loop.py new file mode 100644 index 0000000000..f7ed4d3da6 --- /dev/null +++ b/bin/tests/system/resend_loop/tests_resend_loop.py @@ -0,0 +1,28 @@ +# Copyright (C) Internet Systems Consortium, Inc. ("ISC") +# +# SPDX-License-Identifier: MPL-2.0 +# +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, you can obtain one at https://mozilla.org/MPL/2.0/. +# +# See the COPYRIGHT file distributed with this work for additional +# information regarding copyright ownership. + +import dns.message + +import isctest + + +def test_resend_loop_badcookie(ns4): + expected_log = "exceeded max queries resolving 'test.example/A'" + + msg = dns.message.make_query("test.example", "A") + with ns4.watch_log_from_here() as watcher: + res = isctest.query.udp(msg, ns4.ip) + watcher.wait_for_line(expected_log) + + isctest.check.servfail(res) + + prohibited_log = "query failed (timed out) for test.example/IN/A" + assert prohibited_log not in ns4.log