1 # Copyright 2014 The Chromium OS Authors. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 import dpkt 6 import logging 7 import re 8 9 from autotest_lib.client.bin import test 10 from autotest_lib.client.common_lib import error 11 from autotest_lib.client.common_lib.cros.tendo import peerd_config 12 from autotest_lib.client.cros import chrooted_avahi 13 from autotest_lib.client.cros.netprotos import interface_host 14 from autotest_lib.client.cros.netprotos import zeroconf 15 from autotest_lib.client.cros.tendo import peerd_dbus_helper 16 17 18 class peerd_AdvertiseServices(test.test): 19 """Test that peerd can correctly advertise services over mDNS.""" 20 version = 1 21 22 ANY_VALUE = object() # Use reference equality for wildcard. 23 FAKE_HOST_HOSTNAME = 'test-host' 24 TEST_TIMEOUT_SECONDS = 30 25 TEST_SERVICE_ID = 'test-service-0' 26 TEST_SERVICE_INFO = {'some_data': 'a value', 27 'other_data': 'another value'} 28 TEST_SERVICE_PORT = 8080 29 SERBUS_SERVICE_ID = 'serbus' 30 SERBUS_SERVICE_INFO = { 31 'ver': '1.0', 32 'id': ANY_VALUE, 33 'services': r'(.+\.)?' + TEST_SERVICE_ID + r'(\..+)?', 34 } 35 SERBUS_SERVICE_PORT = 0 36 37 38 def initialize(self): 39 # Make sure these are initiallized to None in case we throw 40 # during self.initialize(). 41 self._chrooted_avahi = None 42 self._peerd = None 43 self._host = None 44 self._zc_listener = None 45 self._chrooted_avahi = chrooted_avahi.ChrootedAvahi() 46 self._chrooted_avahi.start() 47 # Start up a cleaned up peerd with really verbose logging. 48 self._peerd = peerd_dbus_helper.make_helper( 49 peerd_config.PeerdConfig(verbosity_level=3)) 50 # Listen on our half of the interface pair for mDNS advertisements. 51 self._host = interface_host.InterfaceHost( 52 self._chrooted_avahi.unchrooted_interface_name) 53 self._zc_listener = zeroconf.ZeroconfDaemon(self._host, 54 self.FAKE_HOST_HOSTNAME) 55 # The queries for hostname/dns_domain are IPCs and therefor relatively 56 # expensive. Do them just once. 57 hostname = self._chrooted_avahi.hostname 58 dns_domain = self._chrooted_avahi.dns_domain 59 if not hostname or not dns_domain: 60 raise error.TestFail('Failed to get hostname/domain from avahi.') 61 self._dns_domain = dns_domain 62 self._hostname = '%s.%s' % (hostname, dns_domain) 63 64 65 def cleanup(self): 66 for obj in (self._chrooted_avahi, 67 self._host, 68 self._peerd): 69 if obj is not None: 70 obj.close() 71 72 73 def _check_txt_record_data(self, expected_data, actual_data): 74 # Labels in the TXT record should be 1:1 with our service info. 75 expected_entries = expected_data.copy() 76 for entry in actual_data: 77 # All labels should be key/value pairs. 78 if entry.find('=') < 0: 79 raise error.TestFail('All TXT entries should have = separator, ' 80 'but got: %s' % entry) 81 k, v = entry.split('=', 1) 82 if k not in expected_entries: 83 raise error.TestFail('Unexpected TXT entry key: %s' % k) 84 if (expected_entries[k] != self.ANY_VALUE and 85 not re.match(expected_entries[k], v)): 86 # We're going to return False here rather than fail the test 87 # for one tricky reason: in the root serbus record, we may 88 # find that the service list does not match our expectation 89 # since other daemons may be advertising services via peerd. 90 # We need to basically wait for our test service to show up. 91 logging.warning('Expected TXT value to match %s for ' 92 'entry=%s but got value=%r instead.', 93 expected_entries[k], k, v) 94 return False 95 expected_entries.pop(k) 96 if expected_entries: 97 # Raise a detailed exception here, rather than return false. 98 raise error.TestFail('Missing entries from TXT: %r' % 99 expected_entries) 100 return True 101 102 103 def _ask_for_record(self, record_name, record_type): 104 """Ask for a record, and query for it if we don't have it. 105 106 @param record_name: string name of record (e.g. the complete host name 107 for A records. 108 @param record_type: one of dpkt.dns.DNS_*. 109 @return list of matching records. 110 111 """ 112 found_records = self._zc_listener.cached_results( 113 record_name, record_type) 114 if len(found_records) > 1: 115 logging.warning('Found multiple records with name=%s and type=%r', 116 record_name, record_type) 117 if found_records: 118 logging.debug('Found record with name=%s, type=%r, value=%r.', 119 record_name, record_type, found_records[0].data) 120 return found_records[0] 121 logging.debug('Did not see record with name=%s and type=%r', 122 record_name, record_type) 123 desired_records = [(record_name, record_type)] 124 self._zc_listener.send_request(desired_records) 125 return None 126 127 128 def _found_service_records(self, service_id, service_info, service_port): 129 PTR_name = '_%s._tcp.%s' % (service_id, self._dns_domain) 130 record_PTR = self._ask_for_record(PTR_name, dpkt.dns.DNS_PTR) 131 if not record_PTR: 132 return False 133 # Great, we know the PTR, make sure that we can also get the SRV and 134 # TXT entries. 135 TXT_name = SRV_name = record_PTR.data 136 record_SRV = self._ask_for_record(SRV_name, dpkt.dns.DNS_SRV) 137 if record_SRV is None: 138 return False 139 if (record_SRV.data[0] != self._hostname or 140 record_SRV.data[3] != service_port): 141 raise error.TestFail('Expected SRV record data %r but got %r' % 142 ((self._hostname, service_port), 143 record_SRV.data)) 144 # TXT should exist. 145 record_TXT = self._ask_for_record(TXT_name, dpkt.dns.DNS_TXT) 146 if (record_TXT is None or 147 not self._check_txt_record_data(service_info, record_TXT.data)): 148 return False 149 return True 150 151 152 def _found_desired_records(self): 153 """Verifies that avahi has all the records we care about. 154 155 Asks the |self._zc_listener| for records we expect to correspond 156 to our test service. Will trigger queries if we don't find the 157 expected records. 158 159 @return True if we have all expected records, False otherwise. 160 161 """ 162 logging.debug('Looking for records for %s.', self._hostname) 163 # First, check that Avahi is doing the simple things and publishing 164 # an A record. 165 record_A = self._ask_for_record(self._hostname, dpkt.dns.DNS_A) 166 if (record_A is None or 167 record_A.data != self._chrooted_avahi.avahi_interface_addr): 168 return False 169 logging.debug('Found A record, looking for serbus records.') 170 # If we can see Avahi publishing that it's there, check that it has 171 # appropriate entries for its serbus master record. 172 if not self._found_service_records(self.SERBUS_SERVICE_ID, 173 self.SERBUS_SERVICE_INFO, 174 self.SERBUS_SERVICE_PORT): 175 return False 176 logging.debug('Found serbus records, looking for service records.') 177 # We also expect the subservices we've added to exist. 178 if not self._found_service_records(self.TEST_SERVICE_ID, 179 self.TEST_SERVICE_INFO, 180 self.TEST_SERVICE_PORT): 181 return False 182 logging.debug('Found all desired records.') 183 return True 184 185 186 def run_once(self): 187 # Tell peerd about this exciting new service we have. 188 self._peerd.expose_service( 189 self.TEST_SERVICE_ID, 190 self.TEST_SERVICE_INFO, 191 mdns_options={'port': self.TEST_SERVICE_PORT}) 192 # Wait for advertisements of that service to appear from avahi. 193 logging.info('Waiting to receive mDNS advertisements of ' 194 'peerd services.') 195 success, duration = self._host.run_until(self._found_desired_records, 196 self.TEST_TIMEOUT_SECONDS) 197 if not success: 198 raise error.TestFail('Did not receive mDNS advertisements in time.') 199
