from twisted.internet import defer
from twisted.python import failure
+from invirt.common import InvirtConfigError
from invirt.config import structs as config
import invirt.database
import psycopg2
import sqlalchemy
import time
+import re
class DatabaseAuthority(common.ResolverBase):
"""An Authority that is loaded from a file."""
if name in self.domains:
domain = name
else:
- # Look for the longest-matching domain. (This works because domain
- # will remain bound after breaking out of the loop.)
+ # Look for the longest-matching domain.
best_domain = ''
for domain in self.domains:
if name.endswith('.'+domain) and len(domain) > len(best_domain):
best_domain = domain
if best_domain == '':
- return defer.fail(failure.Failure(dns.DomainError(name)))
+ if name.endswith('.in-addr.arpa'):
+ # Act authoritative for the IP address for reverse resolution requests
+ best_domain = name
+ else:
+ return defer.fail(failure.Failure(dns.DomainError(name)))
domain = best_domain
results = []
authority = []
if cls == dns.IN:
host = name[:-len(domain)-1]
- if not host: # Request for the domain itself.
+ if not host and type != dns.PTR: # Request for the domain itself.
if type in (dns.A, dns.ALL_RECORDS):
record = dns.Record_A(config.dns.nameservers[0].ip, ttl)
results.append(dns.RRHeader(name, dns.A, dns.IN,
results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
ttl, self.soa, auth=True))
else: # Request for a subdomain.
- value = invirt.database.Machine.query().filter_by(name=host).first()
- 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 name.endswith(".in-addr.arpa"): # Reverse resolution here
+ if type in (dns.PTR, dns.ALL_RECORDS):
+ ip = '.'.join(reversed(name.split('.')[:-2]))
+ value = invirt.database.NIC.query.filter_by(ip=ip).first()
+ if value and value.hostname:
+ hostname = value.hostname
+ if '.' not in hostname:
+ hostname = hostname + "." + config.dns.domains[0]
+ record = dns.Record_PTR(hostname, ttl)
+ results.append(dns.RRHeader(name, dns.PTR, dns.IN,
+ ttl, record, auth=True))
+ else: # IP address doesn't point to an active host
+ return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
+ # FIXME: Should only return success with no records if the name actually exists
+ else: # Forward resolution here
+ value = invirt.database.NIC.query.filter_by(hostname=host).first()
+ if value:
+ ip = value.ip
+ else:
+ value = invirt.database.Machine.query().filter_by(name=host).first()
+ if value:
+ ip = value.nics[0].ip
+ else:
+ return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
+
+ if ip is None:
+ 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.SOA:
- results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
- ttl, self.soa, auth=True))
+ 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.SOA:
+ results.append(dns.RRHeader(domain, dns.SOA, dns.IN,
+ ttl, self.soa, auth=True))
if len(results) == 0:
authority = []
additional = []
#Doesn't exist
return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
+class QuotingBindAuthority(authority.BindAuthority):
+ """
+ A BindAuthority that (almost) deals with quoting correctly
+
+ This will catch double quotes as marking the start or end of a
+ quoted phrase, unless the double quote is escaped by a backslash
+ """
+ # Match either a quoted or unquoted string literal followed by
+ # whitespace or the end of line. This yields two groups, one of
+ # which has a match, and the other of which is None, depending on
+ # whether the string literal was quoted or unquoted; this is what
+ # necessitates the subsequent filtering out of groups that are
+ # None.
+ string_pat = \
+ re.compile(r'"((?:[^"\\]|\\.)*)"|((?:[^\\\s]|\\.)+)(?:\s+|\s*$)')
+
+ # For interpreting escapes.
+ escape_pat = re.compile(r'\\(.)')
+
+ def collapseContinuations(self, lines):
+ L = []
+ state = 0
+ for line in lines:
+ if state == 0:
+ if line.find('(') == -1:
+ L.append(line)
+ else:
+ L.append(line[:line.find('(')])
+ state = 1
+ else:
+ if line.find(')') != -1:
+ L[-1] += ' ' + line[:line.find(')')]
+ state = 0
+ else:
+ L[-1] += ' ' + line
+ lines = L
+ L = []
+
+ for line in lines:
+ in_quote = False
+ split_line = []
+ for m in self.string_pat.finditer(line):
+ [x] = [x for x in m.groups() if x is not None]
+ split_line.append(self.escape_pat.sub(r'\1', x))
+ L.append(split_line)
+ return filter(None, L)
+
if '__main__' == __name__:
resolvers = []
- for zone in config.dns.zone_files:
- for origin in config.dns.domains:
- r = authority.BindAuthority(zone)
- # This sucks, but if I want a generic zone file, I have to
- # reload the information by hand
- r.origin = origin
- lines = open(zone).readlines()
- lines = r.collapseContinuations(r.stripComments(lines))
- r.parseLines(lines)
-
- resolvers.append(r)
+ try:
+ for zone in config.dns.zone_files:
+ for origin in config.dns.domains:
+ r = QuotingBindAuthority(zone)
+ # This sucks, but if I want a generic zone file, I have to
+ # reload the information by hand
+ r.origin = origin
+ lines = open(zone).readlines()
+ lines = r.collapseContinuations(r.stripComments(lines))
+ r.parseLines(lines)
+
+ resolvers.append(r)
+ except InvirtConfigError:
+ # Don't care if zone_files isn't defined
+ pass
resolvers.append(DatabaseAuthority())
verbosity = 0
projects / invirt/packages/invirt-dns.git / blobdiff