"""
Domain Name Server
"""
import os, traceback
from twisted.python import usage
from twisted.protocols import dns
from twisted.application import internet, service
from twisted.names import server
from twisted.names import authority
from twisted.names import secondary
class Options(usage.Options):
optParameters = [
["interface", "i", "", "The interface to which to bind"],
["port", "p", "53", "The port on which to listen"],
["resolv-conf", None, None,
"Override location of resolv.conf (implies --recursive)"],
]
optFlags = [
["cache", "c", "Enable record caching"],
["recursive", "r", "Perform recursive lookups"],
["iterative", "I", "Perform lookups using the root servers"],
["verbose", "v", "Log verbosely"]
]
zones = None
zonefiles = None
def __init__(self):
usage.Options.__init__(self)
self['verbose'] = 0
self.bindfiles = []
self.zonefiles = []
self.secondaries = []
def opt_pyzone(self, filename):
"""Specify the filename of a Python syntax zone definition"""
if not os.path.exists(filename):
raise usage.UsageError(filename + ": No such file")
self.zonefiles.append(filename)
def opt_bindzone(self, filename):
"""Specify the filename of a BIND9 syntax zone definition"""
if not os.path.exists(filename):
raise usage.UsageError(filename + ": No such file")
self.bindfiles.append(filename)
def opt_secondary(self, ip_domain):
"""Act as secondary for the specified domain, performing
zone transfers from the specified IP (IP/domain)
"""
args = ip_domain.split('/', 1)
if len(args) != 2:
raise usage.UsageError("Argument must be of the form IP/domain")
self.secondaries.append((args[0], [args[1]]))
def opt_verbose(self):
"""Increment verbosity level"""
self['verbose'] += 1
def postOptions(self):
if self['resolv-conf']:
self['recursive'] = True
if self['iterative'] and self['recursive']:
raise usage.UsageError("--iterative and --recursive are mutually exclusive.")
self.svcs = []
self.zones = []
for f in self.zonefiles:
try:
self.zones.append(authority.PySourceAuthority(f))
except Exception, e:
traceback.print_exc()
raise usage.UsageError("Invalid syntax in " + f)
for f in self.bindfiles:
try:
self.zones.append(authority.BindAuthority(f))
except Exception, e:
traceback.print_exc()
raise usage.UsageError("Invalid syntax in " + f)
for f in self.secondaries:
self.svcs.append(secondary.SecondaryAuthorityService(*f))
self.zones.append(self.svcs[-1].getAuthority())
try:
self['port'] = int(self['port'])
except ValueError:
raise usage.UsageError("Invalid port: %r" % (self['port'],))
def makeService(config):
import client, cache
ca, cl = [], []
if config['cache']:
ca.append(cache.CacheResolver(verbose=config['verbose']))
if config['recursive']:
cl.append(client.createResolver(resolvconf=config['resolv-conf']))
f = server.DNSServerFactory(config.zones, ca, cl, config['verbose'])
p = dns.DNSDatagramProtocol(f)
f.noisy = 0
ret = service.MultiService()
for (klass, arg) in [(internet.TCPServer, f), (internet.UDPServer, p)]:
s = klass(config['port'], arg, interface=config['interface'])
s.setServiceParent(ret)
for svc in config.svcs:
svc.setServiceParent(ret)
return ret