YARN-8410. Fixed a bug in A record lookup by CNAME record.

Contributed by Shane Kumpf
This commit is contained in:
Eric Yang 2018-06-14 15:54:21 -04:00
parent 8d4926f38b
commit 9591765040
2 changed files with 44 additions and 8 deletions

View File

@ -1126,19 +1126,38 @@ public class RegistryDNS extends AbstractService implements DNSOperations,
*/
private byte remoteLookup(Message response, Name name, int type,
int iterations) {
// If retrieving the root zone, query for NS record type
if (name.toString().equals(".")) {
type = Type.NS;
}
// Always add any CNAMEs to the response first
if (type != Type.CNAME) {
Record[] cnameAnswers = getRecords(name, Type.CNAME);
if (cnameAnswers != null) {
for (Record cnameR : cnameAnswers) {
if (!response.findRecord(cnameR)) {
response.addRecord(cnameR, Section.ANSWER);
}
}
}
}
// Forward lookup to primary DNS servers
Record[] answers = getRecords(name, type);
try {
for (Record r : answers) {
if (r.getType() == Type.SOA) {
response.addRecord(r, Section.AUTHORITY);
} else {
response.addRecord(r, Section.ANSWER);
if (!response.findRecord(r)) {
if (r.getType() == Type.SOA) {
response.addRecord(r, Section.AUTHORITY);
} else {
response.addRecord(r, Section.ANSWER);
}
}
if (r.getType() == Type.CNAME) {
Name cname = ((CNAMERecord) r).getAlias();
if (iterations < 6) {
remoteLookup(response, cname, Type.CNAME, iterations + 1);
remoteLookup(response, cname, type, iterations + 1);
}
}
}

View File

@ -410,7 +410,7 @@ public class TestRegistryDNS extends Assert {
return recs;
}
Record[] assertDNSQueryNotNull(String lookup, int type)
Record[] assertDNSQueryNotNull(String lookup, int type, int answerCount)
throws IOException {
Name name = Name.fromString(lookup);
Record question = Record.newRecord(name, type, DClass.IN);
@ -424,7 +424,7 @@ public class TestRegistryDNS extends Assert {
assertEquals("Questions do not match", query.getQuestion(),
response.getQuestion());
Record[] recs = response.getSectionArray(Section.ANSWER);
assertEquals(1, recs.length);
assertEquals(answerCount, recs.length);
assertEquals(recs[0].getType(), type);
return recs;
}
@ -656,7 +656,24 @@ public class TestRegistryDNS extends Assert {
// start assessing whether correct records are available
Record[] recs =
assertDNSQueryNotNull("mail.yahoo.com.", Type.CNAME);
assertDNSQueryNotNull("mail.yahoo.com.", Type.CNAME, 1);
}
@Test
public void testRootLookup() throws Exception {
setRegistryDNS(new RegistryDNS("TestRegistry"));
Configuration conf = new Configuration();
conf.set(RegistryConstants.KEY_DNS_DOMAIN, "dev.test");
conf.set(RegistryConstants.KEY_DNS_ZONE_SUBNET, "172.17.0");
conf.setTimeDuration(RegistryConstants.KEY_DNS_TTL, 30L, TimeUnit.SECONDS);
conf.set(RegistryConstants.KEY_DNS_ZONES_DIR,
getClass().getResource("/").getFile());
getRegistryDNS().setDomainName(conf);
getRegistryDNS().initializeZones(conf);
// start assessing whether correct records are available
Record[] recs =
assertDNSQueryNotNull(".", Type.NS, 13);
}
@Test