unittests/CNameRecordTests.c

   1 #include "CNameRecordTests.h"
   2 #include "unittest_common.h"
   3
   4 mDNSlocal int InitThisUnitTest(void);
   5 mDNSlocal int StartClientQueryRequest(void);
   6 mDNSlocal int PopulateCacheWithClientResponseRecords(void);
   7 mDNSlocal int SimulateNetworkChangeAndVerifyTest(void);
   8 mDNSlocal int FinalizeUnitTest(void);
   9 mDNSlocal mStatus AddDNSServer(void);
  10
  11 // This unit test's variables
  12 static UDPSocket* local_socket;
  13 static request_state* client_request_message;
  14
  15 struct UDPSocket_struct
  16 {
  17         mDNSIPPort port; // MUST BE FIRST FIELD -- mDNSCoreReceive expects every UDPSocket_struct to begin with mDNSIPPort port
  18 };
  19 typedef struct UDPSocket_struct UDPSocket;
  20
  21 // This client request was generated using the following command: "dns-sd -Q 123server.dotbennu.com. A".
  22 uint8_t query_client_msgbuf[35] = {
  23         0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x31, 0x32, 0x33, 0x73, 0x65, 0x72, 0x76, 0x65,
  24         0x72, 0x2e, 0x64, 0x6f, 0x74, 0x62, 0x65, 0x6e, 0x6e, 0x75, 0x2e, 0x63, 0x6f, 0x6d, 0x00, 0x00,
  25         0x01, 0x00, 0x01
  26 };
  27
  28 // This uDNS message is a canned response that was originally captured by wireshark.
  29 uint8_t query_response_msgbuf[108] = {
  30     0x69, 0x41, // transaction id
  31         0x85, 0x80, // flags
  32         0x00, 0x01, // 1 question for 123server.dotbennu.com. Addr
  33         0x00, 0x02,     // 2 anwsers: 123server.dotbennu.com. CNAME test212.dotbennu.com., test212.dotbennu.com. Addr 10.100.0.1,
  34         0x00, 0x01,     // 1 authorities anwser: dotbennu.com. NS cardinal2.apple.com.
  35         0x00, 0x00, 0x09, 0x31, 0x32, 0x33,
  36     0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x08, 0x64, 0x6f, 0x74, 0x62, 0x65, 0x6e, 0x6e, 0x75, 0x03,
  37     0x63, 0x6f, 0x6d, 0x00, 0x00, 0x01, 0x00, 0x01, 0xc0, 0x0c, 0x00, 0x05, 0x00, 0x01, 0x00, 0x00,
  38     0x02, 0x56, 0x00, 0x0a, 0x07, 0x74, 0x65, 0x73, 0x74, 0x32, 0x31, 0x32, 0xc0, 0x16, 0xc0, 0x34,
  39     0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x00, 0x0a, 0x00, 0x04, 0x0a, 0x64, 0x00, 0x01, 0xc0, 0x16,
  40     0x00, 0x02, 0x00, 0x01, 0x00, 0x01, 0x51, 0x80, 0x00, 0x12, 0x09, 0x63, 0x61, 0x72, 0x64, 0x69,
  41     0x6e, 0x61, 0x6c, 0x32, 0x05, 0x61, 0x70, 0x70, 0x6c, 0x65, 0xc0, 0x1f
  42 };
  43
  44 // Variables associated with contents of the above uDNS message
  45 #define uDNS_TargetQID 16745
  46 char udns_original_domainname_cstr[] = "123server.dotbennu.com.";
  47 char udns_cname_domainname_cstr[] = "test212.dotbennu.com.";
  48 static const mDNSv4Addr dns_response_ipv4 = {{ 10, 100, 0, 1 }};
  49
  50 UNITTEST_HEADER(CNameRecordTests)
  51         UNITTEST_TEST(InitThisUnitTest)
  52         UNITTEST_TEST(StartClientQueryRequest)
  53     UNITTEST_TEST(PopulateCacheWithClientResponseRecords)
  54     UNITTEST_TEST(SimulateNetworkChangeAndVerifyTest)
  55     UNITTEST_TEST(FinalizeUnitTest)
  56 UNITTEST_FOOTER
  57
  58 // The InitThisUnitTest() initializes the mDNSResponder environment as well as
  59 // a DNSServer. It also allocates memory for a local_socket and client request.
  60 // Note: This unit test does not send packets on the wire and it does not open sockets.
  61 UNITTEST_HEADER(InitThisUnitTest)
  62         // Init unit test environment and verify no error occurred.
  63         mStatus result = init_mdns_environment(mDNStrue);
  64         UNITTEST_ASSERT(result == mStatus_NoError);
  65
  66         // Add one DNS server and verify it was added.
  67         AddDNSServer();
  68         UNITTEST_ASSERT(NumUnicastDNSServers == 1);
  69
  70         // Create memory for a socket that is never used or opened.
  71         local_socket = mDNSPlatformMemAllocate(sizeof(UDPSocket));
  72         mDNSPlatformMemZero(local_socket, sizeof(UDPSocket));
  73
  74         // Create memory for a request that is used to make this unit test's client request.
  75         client_request_message = calloc(1, sizeof(request_state));
  76 UNITTEST_FOOTER
  77
  78 // This test simulates a uds client request by setting up a client request and then
  79 // calling mDNSResponder's handle_client_request.  The handle_client_request function
  80 // processes the request and starts a query.  This unit test verifies
  81 // the client request and query were setup as expected.  This unit test also calls
  82 // mDNS_execute which determines the cache does not contain the new question's
  83 // answer.
  84 UNITTEST_HEADER(StartClientQueryRequest)
  85     mDNS *const m = &mDNSStorage;
  86     request_state* req = client_request_message;
  87         char *msgptr = (char *)query_client_msgbuf;
  88         size_t msgsz = sizeof(query_client_msgbuf);
  89         mDNSs32 min_size = sizeof(DNSServiceFlags) + sizeof(mDNSu32) + 4;
  90     DNSQuestion *q;
  91     mStatus err = mStatus_NoError;
  92         char qname_cstr[MAX_ESCAPED_DOMAIN_NAME];
  93
  94     // Process the unit test's client request
  95         start_client_request(req, msgptr, msgsz, query_request, local_socket);
  96     UNITTEST_ASSERT(err == mStatus_NoError);
  97
  98         // Verify the request fields were set as expected
  99         UNITTEST_ASSERT(req->next == mDNSNULL);
 100         UNITTEST_ASSERT(req->primary == mDNSNULL);
 101         UNITTEST_ASSERT(req->sd == client_req_sd);
 102         UNITTEST_ASSERT(req->process_id == client_req_process_id);
 103         UNITTEST_ASSERT(!strcmp(req->pid_name, client_req_pid_name));
 104         UNITTEST_ASSERT(req->validUUID == mDNSfalse);
 105         UNITTEST_ASSERT(req->errsd == 0);
 106         UNITTEST_ASSERT(req->uid == client_req_uid);
 107         UNITTEST_ASSERT(req->ts == t_complete);
 108         UNITTEST_ASSERT((mDNSs32)req->data_bytes > min_size);
 109         UNITTEST_ASSERT(req->msgend == msgptr+msgsz);
 110         UNITTEST_ASSERT(req->msgbuf == mDNSNULL);
 111     UNITTEST_ASSERT(req->hdr.version == VERSION);
 112     UNITTEST_ASSERT(req->replies == mDNSNULL);
 113     UNITTEST_ASSERT(req->terminate != mDNSNULL);
 114         UNITTEST_ASSERT(req->flags == kDNSServiceFlagsReturnIntermediates);
 115     UNITTEST_ASSERT(req->interfaceIndex == kDNSServiceInterfaceIndexAny);
 116
 117         // Verify the query fields were set as expected
 118         q = &req->u.queryrecord.q;
 119     UNITTEST_ASSERT(q != mDNSNULL);
 120     UNITTEST_ASSERT(q == m->Questions);
 121     UNITTEST_ASSERT(q == m->NewQuestions);
 122     UNITTEST_ASSERT(q->SuppressUnusable == mDNSfalse);
 123     UNITTEST_ASSERT(q->ReturnIntermed == mDNStrue);
 124     UNITTEST_ASSERT(q->SuppressQuery == mDNSfalse);
 125
 126         UNITTEST_ASSERT(q->qnameOrig == mDNSNULL);
 127         ConvertDomainNameToCString(&q->qname, qname_cstr);
 128         UNITTEST_ASSERT(!strcmp(qname_cstr, udns_original_domainname_cstr));
 129         UNITTEST_ASSERT(q->qnamehash == DomainNameHashValue(&q->qname));
 130
 131         UNITTEST_ASSERT(q->InterfaceID == mDNSInterface_Any);
 132     UNITTEST_ASSERT(q->flags == req->flags);
 133     UNITTEST_ASSERT(q->qtype == 1);
 134     UNITTEST_ASSERT(q->qclass == 1);
 135     UNITTEST_ASSERT(q->LongLived == 0);
 136     UNITTEST_ASSERT(q->ExpectUnique == mDNSfalse);
 137     UNITTEST_ASSERT(q->ForceMCast == 0);
 138     UNITTEST_ASSERT(q->TimeoutQuestion == 0);
 139     UNITTEST_ASSERT(q->WakeOnResolve == 0);
 140     UNITTEST_ASSERT(q->UseBackgroundTrafficClass == 0);
 141     UNITTEST_ASSERT(q->ValidationRequired == 0);
 142     UNITTEST_ASSERT(q->ValidatingResponse == 0);
 143     UNITTEST_ASSERT(q->ProxyQuestion == 0);
 144     UNITTEST_ASSERT(q->AnonInfo == mDNSNULL);
 145     UNITTEST_ASSERT(q->QuestionCallback != mDNSNULL);
 146     UNITTEST_ASSERT(q->QuestionContext == req);
 147     UNITTEST_ASSERT(q->SearchListIndex == 0);
 148     UNITTEST_ASSERT(q->DNSSECAuthInfo == mDNSNULL);
 149     UNITTEST_ASSERT(q->DAIFreeCallback == mDNSNULL);
 150     UNITTEST_ASSERT(q->RetryWithSearchDomains == 0);
 151     UNITTEST_ASSERT(q->AppendSearchDomains == 0);
 152     UNITTEST_ASSERT(q->AppendLocalSearchDomains == 0);
 153     UNITTEST_ASSERT(q->DuplicateOf == mDNSNULL);
 154
 155     // Call mDNS_Execute to see if the new question, q, has an answer in the cache.
 156         // It won't be yet because the cache is empty.
 157         m->NextScheduledEvent = mDNS_TimeNow_NoLock(m);
 158     mDNS_Execute(m);
 159
 160     // Verify mDNS_Execute processed the new question.
 161         UNITTEST_ASSERT(m->NewQuestions == mDNSNULL);
 162
 163         // Verify the cache is empty and the request got no reply.
 164         UNITTEST_ASSERT(m->rrcache_totalused == 0);
 165     UNITTEST_ASSERT(req->replies == mDNSNULL);
 166
 167 UNITTEST_FOOTER
 168
 169 // This unit test receives a canned uDNS response message by calling the mDNSCoreReceive() function.
 170 // It then verifies cache entries were added for the CNAME and A records that were contained in the
 171 // answers of the canned response, query_response_msgbuf.  This unit test also verifies that
 172 // 2 add events were generated for the client.
 173 UNITTEST_HEADER(PopulateCacheWithClientResponseRecords)
 174     mDNS *const m = &mDNSStorage;
 175         DNSMessage *msgptr = (DNSMessage *)query_response_msgbuf;
 176         size_t msgsz = sizeof(query_response_msgbuf);
 177     struct reply_state *reply;
 178     request_state* req = client_request_message;
 179     DNSQuestion *q = &req->u.queryrecord.q;
 180     const char *data;
 181         const char *end;
 182     char name[kDNSServiceMaxDomainName];
 183     uint16_t rrtype, rrclass, rdlen;
 184     const char *rdata;
 185     size_t len;
 186     char domainname_cstr[MAX_ESCAPED_DOMAIN_NAME];
 187
 188         // Receive and populate the cache with canned response
 189     receive_response(req, msgptr, msgsz);
 190
 191     // Verify 2 cache entries for CName and A record are present
 192     mDNSu32 CacheUsed =0, notUsed =0;
 193     LogCacheRecords_ut(mDNS_TimeNow(m), &CacheUsed, &notUsed);
 194     UNITTEST_ASSERT(CacheUsed == m->rrcache_totalused);
 195     UNITTEST_ASSERT(CacheUsed  == 4); // 2 for the CacheGroup object plus 2 for the A and CNAME records
 196     UNITTEST_ASSERT(m->PktNum  == 1); // one packet was received
 197
 198         // Verify question's qname is now set with the A record's domainname
 199         UNITTEST_ASSERT(q->qnameOrig == mDNSNULL);
 200         ConvertDomainNameToCString(&q->qname, domainname_cstr);
 201         UNITTEST_ASSERT(q->qnamehash == DomainNameHashValue(&q->qname));
 202         UNITTEST_ASSERT(!strcmp(domainname_cstr, udns_cname_domainname_cstr));
 203
 204         // Verify client's add event for CNAME is properly formed
 205     reply = req->replies;
 206     UNITTEST_ASSERT(reply != mDNSNULL);
 207     UNITTEST_ASSERT(reply->next == mDNSNULL);
 208
 209     data    = (char *)&reply->rhdr[1];
 210     end     = data+reply->totallen;
 211     get_string(&data, data+reply->totallen, name, kDNSServiceMaxDomainName);
 212     rrtype  = get_uint16(&data, end);
 213     rrclass = get_uint16(&data, end);
 214     rdlen   = get_uint16(&data, end);
 215     rdata   = get_rdata(&data, end, rdlen);
 216         len     = get_reply_len(name, rdlen);
 217
 218     UNITTEST_ASSERT(reply->totallen == len + sizeof(ipc_msg_hdr));
 219     UNITTEST_ASSERT(reply->mhdr->version == VERSION);
 220     UNITTEST_ASSERT(reply->mhdr->datalen == len);
 221     UNITTEST_ASSERT(reply->mhdr->ipc_flags == 0);
 222     UNITTEST_ASSERT(reply->mhdr->op == query_reply_op);
 223
 224     UNITTEST_ASSERT(reply->rhdr->flags == htonl(kDNSServiceFlagsAdd));
 225     UNITTEST_ASSERT(reply->rhdr->ifi == kDNSServiceInterfaceIndexAny);
 226     UNITTEST_ASSERT(reply->rhdr->error == kDNSServiceErr_NoError);
 227
 228     UNITTEST_ASSERT(rrtype == kDNSType_CNAME);
 229     UNITTEST_ASSERT(rrclass == kDNSClass_IN);
 230     ConvertDomainNameToCString((const domainname *const)rdata, domainname_cstr);
 231     UNITTEST_ASSERT(!strcmp(domainname_cstr, "test212.dotbennu.com."));
 232
 233     // The mDNS_Execute call generates an add event for the A record
 234     m->NextScheduledEvent = mDNS_TimeNow_NoLock(m);
 235     mDNS_Execute(m);
 236
 237     // Verify the client's reply contains a properly formed add event for the A record.
 238     reply = req->replies;
 239     UNITTEST_ASSERT(reply != mDNSNULL);
 240     UNITTEST_ASSERT(reply->next != mDNSNULL);
 241     reply = reply->next;
 242
 243     data    = (char *)&reply->rhdr[1];
 244     end     = data+reply->totallen;
 245     get_string(&data, data+reply->totallen, name, kDNSServiceMaxDomainName);
 246     rrtype  = get_uint16(&data, end);
 247     rrclass = get_uint16(&data, end);
 248     rdlen   = get_uint16(&data, end);
 249     rdata   = get_rdata(&data, end, rdlen);
 250         len     = get_reply_len(name, rdlen);
 251
 252     UNITTEST_ASSERT(reply->totallen == len + sizeof(ipc_msg_hdr));
 253     UNITTEST_ASSERT(reply->mhdr->version == VERSION);
 254     UNITTEST_ASSERT(reply->mhdr->datalen == len);
 255
 256     UNITTEST_ASSERT(reply->mhdr->ipc_flags == 0);
 257     UNITTEST_ASSERT(reply->mhdr->op == query_reply_op);
 258
 259     UNITTEST_ASSERT(reply->rhdr->flags == htonl(kDNSServiceFlagsAdd));
 260     UNITTEST_ASSERT(reply->rhdr->ifi == kDNSServiceInterfaceIndexAny);
 261     UNITTEST_ASSERT(reply->rhdr->error == kDNSServiceErr_NoError);
 262
 263     UNITTEST_ASSERT(rrtype == kDNSType_A);
 264     UNITTEST_ASSERT(rrclass == kDNSClass_IN);
 265         UNITTEST_ASSERT(rdata[0] == dns_response_ipv4.b[0]);
 266         UNITTEST_ASSERT(rdata[1] == dns_response_ipv4.b[1]);
 267         UNITTEST_ASSERT(rdata[2] == dns_response_ipv4.b[2]);
 268         UNITTEST_ASSERT(rdata[3] == dns_response_ipv4.b[3]);
 269
 270 UNITTEST_FOOTER
 271
 272 // This function verifies the cache and event handling occurred as expected when a network change happened.
 273 // The uDNS_SetupDNSConfig is called to simulate a network change and two outcomes occur. First the A record
 274 // query is restarted and sent to a new DNS server. Second the cache records are purged. Then mDNS_Execute
 275 // is called and it removes the purged cache records and generates a remove event for the A record.
 276 // The following are verified:
 277 //      1.) The restart of query for A record.
 278 //      2.) The cache is empty after mDNS_Execute removes the cache entres.
 279 //  3.) The remove event is verified by examining the request's reply data.
 280 UNITTEST_HEADER(SimulateNetworkChangeAndVerifyTest)
 281     mDNS *const m = &mDNSStorage;
 282     request_state*  req = client_request_message;
 283     DNSQuestion*    q = &req->u.queryrecord.q;
 284     mDNSu32 CacheUsed =0, notUsed =0;
 285     const char *data;   const char *end;
 286     char name[kDNSServiceMaxDomainName];
 287     uint16_t rrtype, rrclass, rdlen;
 288     const char *rdata;
 289     size_t len;
 290
 291     // The uDNS_SetupDNSConfig reconfigures the resolvers so the A record query is restarted and
 292     // both the CNAME and A record are purged.
 293     uDNS_SetupDNSConfig(m);
 294
 295     // Verify the A record query was restarted.  This is done indirectly by noticing the transaction id and interval have changed.
 296     UNITTEST_ASSERT(q->ThisQInterval == InitialQuestionInterval);
 297     UNITTEST_ASSERT(q->TargetQID.NotAnInteger != uDNS_TargetQID);
 298
 299     // Then mDNS_Execute removes both records from the cache and calls the client back with a remove event for A record.
 300     m->NextScheduledEvent = mDNS_TimeNow_NoLock(m);
 301     mDNS_Execute(m);
 302
 303     // Verify the cache entries are removed
 304     LogCacheRecords_ut(mDNS_TimeNow(m), &CacheUsed, &notUsed);
 305     UNITTEST_ASSERT(CacheUsed == m->rrcache_totalused);
 306     UNITTEST_ASSERT(CacheUsed == 0);
 307
 308     // Verify the A record's remove event is setup as expected in the reply data
 309     struct reply_state *reply;
 310     reply = req->replies;
 311     UNITTEST_ASSERT(reply != mDNSNULL);
 312
 313     UNITTEST_ASSERT(reply != mDNSNULL);
 314     UNITTEST_ASSERT(reply->next != mDNSNULL);
 315     UNITTEST_ASSERT(reply->next->next != mDNSNULL);
 316
 317     reply = reply->next->next; // Get to last event to verify remove event
 318     data    = (char *)&reply->rhdr[1];
 319     end     = data+reply->totallen;
 320     get_string(&data, data+reply->totallen, name, kDNSServiceMaxDomainName);
 321     rrtype  = get_uint16(&data, end);
 322     rrclass = get_uint16(&data, end);
 323     rdlen   = get_uint16(&data, end);
 324     rdata   = get_rdata(&data, end, rdlen);
 325         len     = get_reply_len(name, rdlen);
 326
 327     UNITTEST_ASSERT(reply->totallen == reply->mhdr->datalen + sizeof(ipc_msg_hdr));
 328     UNITTEST_ASSERT(reply->mhdr->version == VERSION);
 329     UNITTEST_ASSERT(reply->mhdr->datalen == len);
 330     UNITTEST_ASSERT(reply->mhdr->ipc_flags == 0);
 331     UNITTEST_ASSERT(reply->mhdr->op == query_reply_op);
 332
 333     UNITTEST_ASSERT(reply->rhdr->flags != htonl(kDNSServiceFlagsAdd));
 334     UNITTEST_ASSERT(reply->rhdr->ifi == kDNSServiceInterfaceIndexAny);
 335     UNITTEST_ASSERT(reply->rhdr->error == kDNSServiceErr_NoError);
 336
 337     UNITTEST_ASSERT(rrtype == kDNSType_A);
 338     UNITTEST_ASSERT(rrclass == kDNSClass_IN);
 339         UNITTEST_ASSERT(rdata[0] == dns_response_ipv4.b[0]);
 340         UNITTEST_ASSERT(rdata[1] == dns_response_ipv4.b[1]);
 341         UNITTEST_ASSERT(rdata[2] == dns_response_ipv4.b[2]);
 342         UNITTEST_ASSERT(rdata[3] == dns_response_ipv4.b[3]);
 343
 344 UNITTEST_FOOTER
 345
 346 // This function does memory cleanup and no verification.
 347 UNITTEST_HEADER(FinalizeUnitTest)
 348     mDNS *m = &mDNSStorage;
 349     request_state* req = client_request_message;
 350     DNSServer   *ptr, **p = &m->DNSServers;
 351
 352     while (req->replies)
 353     {
 354         reply_state *reply = req->replies;
 355         req->replies = req->replies->next;
 356                 mDNSPlatformMemFree(reply);
 357     }
 358     mDNSPlatformMemFree(req);
 359
 360     mDNSPlatformMemFree(local_socket);
 361
 362     while (*p)
 363     {
 364         ptr = *p;
 365         *p = (*p)->next;
 366         LogInfo("FinalizeUnitTest: Deleting server %p %#a:%d (%##s)", ptr, &ptr->addr, mDNSVal16(ptr->port), ptr->domain.c);
 367         mDNSPlatformMemFree(ptr);
 368     }
 369 UNITTEST_FOOTER
 370
 371 // The mDNS_AddDNSServer function adds a dns server to mDNSResponder's list.
 372 mDNSlocal mStatus AddDNSServer(void)
 373 {
 374     mDNS *m = &mDNSStorage;
 375     m->timenow = 0;
 376     mDNS_Lock(m);
 377     domainname  d;
 378     mDNSAddr    addr;
 379     mDNSIPPort  port;
 380     mDNSs32             serviceID               = 0;
 381     mDNSu32             scoped                  = 0;
 382     mDNSu32             timeout                 = dns_server_timeout;
 383     mDNSBool    cellIntf                = 0;
 384     mDNSBool    isExpensive             = 0;
 385     mDNSu16             resGroupID              = dns_server_resGroupID;
 386     mDNSBool    reqA                    = mDNStrue;
 387     mDNSBool    reqAAAA                 = mDNStrue;
 388     mDNSBool    reqDO                   = mDNSfalse;
 389     d.c[0]                                              = 0;
 390     addr.type                                   = mDNSAddrType_IPv4;
 391     addr.ip.v4.NotAnInteger             = dns_server_ipv4.NotAnInteger;
 392     port.NotAnInteger                   = client_resp_src_port;
 393         mDNS_AddDNSServer(m, &d, primary_interfaceID, serviceID, &addr, port, scoped, timeout,
 394                       cellIntf, isExpensive, resGroupID,
 395                                           reqA, reqAAAA, reqDO);
 396         mDNS_Unlock(m);
 397         return mStatus_NoError;
 398 }
 399
 400