X-Git-Url: http://xvm.mit.edu/gitweb/invirt/packages/invirt-dns.git/blobdiff_plain/b2a8e274755df081767745b6439e8eb29ac4c9bc..0022277d7474412f25fd51385830537c781af873:/code/dnsserver.py diff --git a/code/dnsserver.py b/code/dnsserver.py deleted file mode 100755 index ae46d4c..0000000 --- a/code/dnsserver.py +++ /dev/null @@ -1,110 +0,0 @@ -#!/usr/bin/python -from twisted.internet import reactor -from twisted.names import server -from twisted.names import dns -from twisted.names import common -from twisted.internet import defer -from twisted.python import failure - -import sipb_xen_database -import psycopg2 -import sqlalchemy -import time - -class DatabaseAuthority(common.ResolverBase): - """An Authority that is loaded from a file.""" - - soa = None - - def __init__(self, domains, database=None): - common.ResolverBase.__init__(self) - if database is not None: - sipb_xen_database.connect(database) - self.domains = domains - self.soa = dns.Record_SOA(mname='sipb-xen-dev.mit.edu', - rname='sipb-xen.mit.edu', - 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): - try: - value = self._lookup_unsafe(name, cls, type, timeout = None) - except (psycopg2.OperationalError, sqlalchemy.exceptions.SQLError): - if i == 2: - raise - print "Reloading database" - time.sleep(0.5) - continue - else: - return value - - def _lookup_unsafe(self, name, cls, type, timeout): - sipb_xen_database.clear_cache() - - ttl = 900 - 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.endswith('.'+domain): - break - else: #Not us - return defer.fail(failure.Failure(dns.DomainError(name))) - results = [] - authority = [] - 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: - record = dns.Record_A('18.181.0.62', ttl) - results.append(dns.RRHeader(name, dns.A, dns.IN, - ttl, record, auth=True)) - else: - 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))) - 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)) - authority = [] - elif type == dns.SOA: - results.append(dns.RRHeader(domain, dns.SOA, dns.IN, - ttl, self.soa, auth=True)) - if len(results) == 0: - authority = [] - additional = [] - return defer.succeed((results, authority, additional)) - else: - #Doesn't exist - return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name))) - -if '__main__' == __name__: - resolver = DatabaseAuthority(['servers.csail.mit.edu', - 'xvm.mit.edu'], - 'postgres://sipb-xen@sipb-xen-dev/sipb_xen') - - verbosity = 0 - f = server.DNSServerFactory(authorities=[resolver], verbose=verbosity) - p = dns.DNSDatagramProtocol(f) - f.noisy = p.noisy = verbosity - - reactor.listenUDP(53, p) - reactor.listenTCP(53, f) - reactor.run()