Restructuring code to correctly return NXDOMAIN on non-A-record requests

[invirt/packages/invirt-dns.git] / code / dnsserver.py

diff --git a/code/dnsserver.py b/code/dnsserver.py
index 9864731..7678db5 100755 (executable)
--- a/code/dnsserver.py
+++ b/code/dnsserver.py
@@ -26,6 +26,10 @@ class DatabaseAuthority(common.ResolverBase):
                                   serial=1, refresh=3600, retry=900,
                                   expire=3600000, minimum=21600, ttl=3600)
         self.ns = dns.Record_NS(name='ns1.xvm.mit.edu', ttl=3600)
+        record = dns.Record_A(address='18.181.0.62', ttl=3600)
+        self.ns1 = dns.RRHeader('ns1.xvm.mit.edu', dns.A, dns.IN,
+                                3600, record, auth=True)
+
     
     def _lookup(self, name, cls, type, timeout = None):
         for i in range(3):
@@ -44,47 +48,53 @@ class DatabaseAuthority(common.ResolverBase):
         sipb_xen_database.clear_cache()
         
         ttl = 900
-        if name.lower() in self.domains:
-            domain = name.lower()
+        name = name.lower()
+        if name in self.domains:
+            domain = name
         else:
             # This works because domain will remain bound after breaking out of the loop
             for domain in self.domains:
-                if name.lower().endswith('.'+domain):
+                if name.endswith('.'+domain):
                     break
             else: #Not us
                 return defer.fail(failure.Failure(dns.DomainError(name)))
         results = []
         authority = []
-        additional = []
+        additional = [self.ns1]
         authority.append(dns.RRHeader(domain, dns.NS, dns.IN,
                                       3600, self.ns, auth=True))
         if cls == dns.IN:
-            if type in (dns.A, dns.ALL_RECORDS):
-                host = name[:-len(domain)-1]
-                if not host:
+            host = name[:-len(domain)-1]
+            if not host:
+                if type in (dns.A, dns.ALL_RECORDS):
                     record = dns.Record_A('18.181.0.62', ttl)
                     results.append(dns.RRHeader(name, dns.A, dns.IN, 
                                                 ttl, record, auth=True))
-                else:
+                elif type == dns.NS:
+                    results.append(dns.RRHeader(domain, dns.NS, dns.IN,
+                                                ttl, self.ns, auth=True))
+                    authority = []
+                elif type == dns.SOA:
+                    results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
+                                                ttl, self.soa, auth=True))
+            else:
+                if host:
                     value = sipb_xen_database.Machine.get_by(name=host)
                     if value is None or not value.nics:
                         return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
                     ip = value.nics[0].ip
                     if ip is None:  #Deactivated?
                         return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
+                if type in (dns.A, dns.ALL_RECORDS):
                     record = dns.Record_A(ip, ttl)
                     results.append(dns.RRHeader(name, dns.A, dns.IN, 
                                                 ttl, record, auth=True))
-            elif type == dns.NS:
-                results.append(dns.RRHeader(domain, dns.NS, dns.IN,
-                                            ttl, self.ns, auth=True))
+                elif type == dns.SOA:
+                    results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
+                                                ttl, self.soa, auth=True))
+            if len(results) == 0:
                 authority = []
-                record = dns.Record_A(address='18.181.0.62', ttl=ttl)
-                additional.append(dns.RRHeader('ns1.xvm.mit.edu', dns.A, dns.IN,
-                                               ttl, record, auth=True))
-            elif type == dns.SOA:
-                results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
-                                            ttl, self.soa, auth=True))
+                additional = []
             return defer.succeed((results, authority, additional))
         else:
             #Doesn't exist