1
# -*- test-case-name: twisted.names.test.test_dns -*-
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# Copyright (c) 2001-2004 Twisted Matrix Laboratories.
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# See LICENSE for details.
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DNS protocol implementation.
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API Stability: Unstable
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- Get rid of some toplevels, maybe.
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- Put in a better lookupRecordType implementation.
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@author: U{Moshe Zadka<mailto:moshez@twistedmatrix.com>},
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U{Jp Calderone<mailto:exarkun@twistedmatrix.com>}
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import struct, random, types, socket
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import cStringIO as StringIO
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AF_INET6 = socket.AF_INET6
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from Crypto.Util import randpool
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for randSource in ('urandom',):
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f = file('/dev/' + randSource)
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def randomSource(r = file('/dev/' + randSource, 'rb').read):
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return struct.unpack('H', r(2))[0]
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"PyCrypto not available - proceeding with non-cryptographically "
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"secure random source",
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return random.randint(0, 65535)
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def randomSource(r = randpool.RandomPool().get_bytes):
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return struct.unpack('H', r(2))[0]
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from zope.interface import implements, Interface
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from twisted.internet import protocol, defer
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from twisted.python import log, failure
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from twisted.python import util as tputil
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(A, NS, MD, MF, CNAME, SOA, MB, MG, MR, NULL, WKS, PTR, HINFO, MINFO, MX, TXT,
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RP, AFSDB) = range(1, 19)
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# 19 through 27? Eh, I'll get to 'em.
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IXFR, AXFR, MAILB, MAILA, ALL_RECORDS = range(251, 256)
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# "Extended" queries (Hey, half of these are deprecated, good job)
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ALL_RECORDS: 'ALL_RECORDS'
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(v, k) for (k, v) in QUERY_TYPES.items() + EXT_QUERIES.items()
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IN, CS, CH, HS = range(1, 5)
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(v, k) for (k, v) in QUERY_CLASSES.items()
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OP_QUERY, OP_INVERSE, OP_STATUS, OP_NOTIFY = range(4)
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OK, EFORMAT, ESERVER, ENAME, ENOTIMP, EREFUSED = range(6)
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class IRecord(Interface):
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"""An single entry in a zone of authority.
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@cvar TYPE: An indicator of what kind of record this is.
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# Backwards compatibility aliases - these should be deprecated or something I
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from twisted.names.error import DomainError, AuthoritativeDomainError
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from twisted.names.error import DNSQueryTimeoutError
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('S', 1), ('M', 60), ('H', 60 * 60), ('D', 60 * 60 * 24),
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('W', 60 * 60 * 24 * 7), ('Y', 60 * 60 * 24 * 365)
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if isinstance(s, types.StringType):
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s = s.upper().strip()
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for (suff, mult) in suffixes:
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return int(float(s[:-1]) * mult)
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raise ValueError, "Invalid time interval specifier: " + s
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def readPrecisely(file, l):
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class IEncodable(Interface):
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Interface for something which can be encoded to and decoded
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def encode(strio, compDict = None):
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Write a representation of this object to the given
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@type strio: File-like object
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@param strio: The stream to which to write bytes
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@type compDict: C{dict} or C{None}
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@param compDict: A dictionary of backreference addresses that have
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have already been written to this stream and that may be used for
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def decode(strio, length = None):
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Reconstruct an object from data read from the given
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@type strio: File-like object
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@param strio: The stream from which bytes may be read
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@type length: C{int} or C{None}
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@param length: The number of bytes in this RDATA field. Most
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implementations can ignore this value. Only in the case of
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records similar to TXT where the total length is in no way
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encoded in the data is it necessary.
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implements(IEncodable)
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def __init__(self, name=''):
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assert isinstance(name, types.StringTypes), "%r is not a string" % (name,)
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def encode(self, strio, compDict=None):
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Encode this Name into the appropriate byte format.
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@param strio: The byte representation of this Name will be written to
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@param compDict: dictionary of Names that have already been encoded
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and whose addresses may be backreferenced by this Name (for the purpose
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of reducing the message size).
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if compDict is not None:
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if compDict.has_key(name):
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struct.pack("!H", 0xc000 | compDict[name]))
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compDict[name] = strio.tell() + Message.headerSize
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label, name = name[:ind], name[ind + 1:]
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label, name = name, ''
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strio.write(chr(ind))
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def decode(self, strio, length = None):
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Decode a byte string into this Name.
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@param strio: Bytes will be read from this file until the full Name
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@raise EOFError: Raised when there are not enough bytes available
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l = ord(readPrecisely(strio, 1))
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new_off = ((l&63) << 8
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| ord(readPrecisely(strio, 1)))
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label = readPrecisely(strio, l)
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self.name = self.name + '.' + label
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def __eq__(self, other):
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if isinstance(other, Name):
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return str(self) == str(other)
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return hash(str(self))
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Represent a single DNS query.
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@ivar name: The name about which this query is requesting information.
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@ivar type: The query type.
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@ivar cls: The query class.
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implements(IEncodable)
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def __init__(self, name='', type=A, cls=IN):
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@param name: The name about which to request information.
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@param type: The query type.
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@param cls: The query class.
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self.name = Name(name)
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def encode(self, strio, compDict=None):
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self.name.encode(strio, compDict)
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strio.write(struct.pack("!HH", self.type, self.cls))
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def decode(self, strio, length = None):
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self.name.decode(strio)
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buff = readPrecisely(strio, 4)
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self.type, self.cls = struct.unpack("!HH", buff)
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return hash((str(self.name).lower(), self.type, self.cls))
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def __cmp__(self, other):
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return isinstance(other, Query) and cmp(
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(str(self.name).lower(), self.type, self.cls),
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(str(other.name).lower(), other.type, other.cls)
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) or cmp(self.__class__, other.__class__)
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t = QUERY_TYPES.get(self.type, EXT_QUERIES.get(self.type, 'UNKNOWN (%d)' % self.type))
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c = QUERY_CLASSES.get(self.cls, 'UNKNOWN (%d)' % self.cls)
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return '<Query %s %s %s>' % (self.name, t, c)
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return 'Query(%r, %r, %r)' % (str(self.name), self.type, self.cls)
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A resource record header.
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@cvar fmt: C{str} specifying the byte format of an RR.
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@ivar name: The name about which this reply contains information.
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@ivar type: The query type of the original request.
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@ivar cls: The query class of the original request.
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@ivar ttl: The time-to-live for this record.
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@ivar payload: An object that implements the IEncodable interface
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@ivar auth: Whether this header is authoritative or not.
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implements(IEncodable)
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cachedResponse = None
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def __init__(self, name='', type=A, cls=IN, ttl=0, payload=None, auth=False):
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@param name: The name about which this reply contains information.
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@param type: The query type.
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@param cls: The query class.
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@param ttl: Time to live for this record.
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@type payload: An object implementing C{IEncodable}
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@param payload: A Query Type specific data object.
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assert (payload is None) or (payload.TYPE == type)
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self.name = Name(name)
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self.payload = payload
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def encode(self, strio, compDict=None):
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self.name.encode(strio, compDict)
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strio.write(struct.pack(self.fmt, self.type, self.cls, self.ttl, 0))
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prefix = strio.tell()
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self.payload.encode(strio, compDict)
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strio.seek(prefix - 2, 0)
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strio.write(struct.pack('!H', aft - prefix))
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def decode(self, strio, length = None):
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self.name.decode(strio)
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l = struct.calcsize(self.fmt)
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buff = readPrecisely(strio, l)
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r = struct.unpack(self.fmt, buff)
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self.type, self.cls, self.ttl, self.rdlength = r
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def isAuthoritative(self):
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t = QUERY_TYPES.get(self.type, EXT_QUERIES.get(self.type, 'UNKNOWN (%d)' % self.type))
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c = QUERY_CLASSES.get(self.cls, 'UNKNOWN (%d)' % self.cls)
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return '<RR name=%s type=%s class=%s ttl=%ds auth=%s>' % (self.name, t, c, self.ttl, self.auth and 'True' or 'False')
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class SimpleRecord(tputil.FancyStrMixin, tputil.FancyEqMixin):
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A Resource Record which consists of a single RFC 1035 domain-name.
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implements(IEncodable, IRecord)
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showAttributes = (('name', 'name', '%s'), 'ttl')
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compareAttributes = ('name', 'ttl')
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def __init__(self, name='', ttl=None):
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self.name = Name(name)
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self.ttl = str2time(ttl)
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def encode(self, strio, compDict = None):
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self.name.encode(strio, compDict)
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def decode(self, strio, length = None):
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self.name.decode(strio)
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return hash(self.name)
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# Kinds of RRs - oh my!
477
class Record_NS(SimpleRecord):
480
class Record_MD(SimpleRecord): # OBSOLETE
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class Record_MF(SimpleRecord): # OBSOLETE
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class Record_CNAME(SimpleRecord):
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class Record_MB(SimpleRecord): # EXPERIMENTAL
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class Record_MG(SimpleRecord): # EXPERIMENTAL
495
class Record_MR(SimpleRecord): # EXPERIMENTAL
498
class Record_PTR(SimpleRecord):
501
class Record_DNAME(SimpleRecord):
504
class Record_A(tputil.FancyEqMixin):
505
implements(IEncodable, IRecord)
510
compareAttributes = ('address', 'ttl')
512
def __init__(self, address='0.0.0.0', ttl=None):
513
address = socket.inet_aton(address)
514
self.address = address
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self.ttl = str2time(ttl)
518
def encode(self, strio, compDict = None):
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strio.write(self.address)
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def decode(self, strio, length = None):
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self.address = readPrecisely(strio, 4)
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return hash(self.address)
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return '<A %s ttl=%s>' % (self.dottedQuad(), self.ttl)
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def dottedQuad(self):
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return socket.inet_ntoa(self.address)
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class Record_SOA(tputil.FancyEqMixin, tputil.FancyStrMixin):
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implements(IEncodable, IRecord)
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compareAttributes = ('serial', 'mname', 'rname', 'refresh', 'expire', 'retry', 'ttl')
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showAttributes = (('mname', 'mname', '%s'), ('rname', 'rname', '%s'), 'serial', 'refresh', 'retry', 'expire', 'minimum', 'ttl')
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def __init__(self, mname='', rname='', serial=0, refresh=0, retry=0, expire=0, minimum=0, ttl=None):
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self.mname, self.rname = Name(mname), Name(rname)
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self.serial, self.refresh = str2time(serial), str2time(refresh)
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self.minimum, self.expire = str2time(minimum), str2time(expire)
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self.retry = str2time(retry)
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self.ttl = str2time(ttl)
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def encode(self, strio, compDict = None):
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self.mname.encode(strio, compDict)
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self.rname.encode(strio, compDict)
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self.serial, self.refresh, self.retry, self.expire,
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def decode(self, strio, length = None):
567
self.mname, self.rname = Name(), Name()
568
self.mname.decode(strio)
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self.rname.decode(strio)
570
r = struct.unpack('!LlllL', readPrecisely(strio, 20))
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self.serial, self.refresh, self.retry, self.expire, self.minimum = r
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self.serial, self.mname, self.rname,
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self.refresh, self.expire, self.retry
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class Record_NULL: # EXPERIMENTAL
582
implements(IEncodable, IRecord)
585
def __init__(self, payload=None, ttl=None):
586
self.payload = payload
587
self.ttl = str2time(ttl)
590
def encode(self, strio, compDict = None):
591
strio.write(self.payload)
594
def decode(self, strio, length = None):
595
self.payload = readPrecisely(strio, length)
599
return hash(self.payload)
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class Record_WKS(tputil.FancyEqMixin, tputil.FancyStrMixin): # OBSOLETE
603
implements(IEncodable, IRecord)
606
compareAttributes = ('address', 'protocol', 'map', 'ttl')
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showAttributes = ('address', 'protocol', 'ttl')
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def __init__(self, address='0.0.0.0', protocol=0, map='', ttl=None):
610
self.address = socket.inet_aton(address)
611
self.protocol, self.map = protocol, map
612
self.ttl = str2time(ttl)
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def encode(self, strio, compDict = None):
616
strio.write(self.address)
617
strio.write(struct.pack('!B', self.protocol))
618
strio.write(self.map)
621
def decode(self, strio, length = None):
622
self.address = readPrecisely(strio, 4)
623
self.protocol = struct.unpack('!B', readPrecisely(strio, 1))[0]
624
self.map = readPrecisely(strio, length - 5)
628
return hash((self.address, self.protocol, self.map))
631
class Record_AAAA(tputil.FancyEqMixin): # OBSOLETE (or headed there)
632
implements(IEncodable, IRecord)
635
compareAttributes = ('address', 'ttl')
637
def __init__(self, address = '::', ttl=None):
638
self.address = socket.inet_pton(AF_INET6, address)
639
self.ttl = str2time(ttl)
642
def encode(self, strio, compDict = None):
643
strio.write(self.address)
646
def decode(self, strio, length = None):
647
self.address = readPrecisely(strio, 16)
651
return hash(self.address)
655
return '<AAAA %s ttl=%s>' % (socket.inet_ntop(AF_INET6, self.address), self.ttl)
659
implements(IEncodable, IRecord)
662
def __init__(self, prefixLen=0, suffix='::', prefix='', ttl=None):
663
self.prefixLen = prefixLen
664
self.suffix = socket.inet_pton(AF_INET6, suffix)
665
self.prefix = Name(prefix)
666
self.bytes = int((128 - self.prefixLen) / 8.0)
667
self.ttl = str2time(ttl)
670
def encode(self, strio, compDict = None):
671
strio.write(struct.pack('!B', self.prefixLen))
673
strio.write(self.suffix[-self.bytes:])
675
# This may not be compressed
676
self.prefix.encode(strio, None)
679
def decode(self, strio, length = None):
680
self.prefixLen = struct.unpack('!B', readPrecisely(strio, 1))[0]
681
self.bytes = int((128 - self.prefixLen) / 8.0)
683
self.suffix = '\x00' * (16 - self.bytes) + readPrecisely(strio, self.bytes)
685
self.prefix.decode(strio)
688
def __eq__(self, other):
689
if isinstance(other, Record_A6):
690
return (self.prefixLen == other.prefixLen and
691
self.suffix[-self.bytes:] == other.suffix[-self.bytes:] and
692
self.prefix == other.prefix and
693
self.ttl == other.ttl)
698
return hash((self.prefixLen, self.suffix[-self.bytes:], self.prefix))
702
return '<A6 %s %s (%d) ttl=%s>' % (
704
socket.inet_ntop(AF_INET6, self.suffix),
705
self.prefixLen, self.ttl
709
class Record_SRV(tputil.FancyEqMixin, tputil.FancyStrMixin): # EXPERIMENTAL
710
implements(IEncodable, IRecord)
713
compareAttributes = ('priority', 'weight', 'target', 'port', 'ttl')
714
showAttributes = ('priority', 'weight', ('target', 'target', '%s'), 'port', 'ttl')
716
def __init__(self, priority=0, weight=0, port=0, target='', ttl=None):
717
self.priority = int(priority)
718
self.weight = int(weight)
719
self.port = int(port)
720
self.target = Name(target)
721
self.ttl = str2time(ttl)
724
def encode(self, strio, compDict = None):
725
strio.write(struct.pack('!HHH', self.priority, self.weight, self.port))
726
# This can't be compressed
727
self.target.encode(strio, None)
730
def decode(self, strio, length = None):
731
r = struct.unpack('!HHH', readPrecisely(strio, struct.calcsize('!HHH')))
732
self.priority, self.weight, self.port = r
734
self.target.decode(strio)
738
return hash((self.priority, self.weight, self.port, self.target))
742
class Record_AFSDB(tputil.FancyStrMixin, tputil.FancyEqMixin):
743
implements(IEncodable, IRecord)
746
compareAttributes = ('subtype', 'hostname', 'ttl')
747
showAttributes = ('subtype', ('hostname', 'hostname', '%s'), 'ttl')
749
def __init__(self, subtype=0, hostname='', ttl=None):
750
self.subtype = int(subtype)
751
self.hostname = Name(hostname)
752
self.ttl = str2time(ttl)
755
def encode(self, strio, compDict = None):
756
strio.write(struct.pack('!H', self.subtype))
757
self.hostname.encode(strio, compDict)
760
def decode(self, strio, length = None):
761
r = struct.unpack('!H', readPrecisely(strio, struct.calcsize('!H')))
763
self.hostname.decode(strio)
767
return hash((self.subtype, self.hostname))
771
class Record_RP(tputil.FancyEqMixin, tputil.FancyStrMixin):
772
implements(IEncodable, IRecord)
775
compareAttributes = ('mbox', 'txt', 'ttl')
776
showAttributes = (('mbox', 'mbox', '%s'), ('txt', 'txt', '%s'), 'ttl')
778
def __init__(self, mbox='', txt='', ttl=None):
779
self.mbox = Name(mbox)
781
self.ttl = str2time(ttl)
784
def encode(self, strio, compDict = None):
785
self.mbox.encode(strio, compDict)
786
self.txt.encode(strio, compDict)
789
def decode(self, strio, length = None):
792
self.mbox.decode(strio)
793
self.txt.decode(strio)
797
return hash((self.mbox, self.txt))
801
class Record_HINFO(tputil.FancyStrMixin):
802
implements(IEncodable, IRecord)
805
showAttributes = ('cpu', 'os', 'ttl')
807
def __init__(self, cpu='', os='', ttl=None):
808
self.cpu, self.os = cpu, os
809
self.ttl = str2time(ttl)
812
def encode(self, strio, compDict = None):
813
strio.write(struct.pack('!B', len(self.cpu)) + self.cpu)
814
strio.write(struct.pack('!B', len(self.os)) + self.os)
817
def decode(self, strio, length = None):
818
cpu = struct.unpack('!B', readPrecisely(strio, 1))[0]
819
self.cpu = readPrecisely(strio, cpu)
820
os = struct.unpack('!B', readPrecisely(strio, 1))[0]
821
self.os = readPrecisely(strio, os)
824
def __eq__(self, other):
825
if isinstance(other, Record_HINFO):
826
return (self.os.lower() == other.os.lower() and
827
self.cpu.lower() == other.cpu.lower() and
828
self.ttl == other.ttl)
833
return hash((self.os.lower(), self.cpu.lower()))
837
class Record_MINFO(tputil.FancyEqMixin, tputil.FancyStrMixin): # EXPERIMENTAL
838
implements(IEncodable, IRecord)
844
compareAttributes = ('rmailbx', 'emailbx', 'ttl')
845
showAttributes = (('rmailbx', 'responsibility', '%s'),
846
('emailbx', 'errors', '%s'),
849
def __init__(self, rmailbx='', emailbx='', ttl=None):
850
self.rmailbx, self.emailbx = Name(rmailbx), Name(emailbx)
851
self.ttl = str2time(ttl)
854
def encode(self, strio, compDict = None):
855
self.rmailbx.encode(strio, compDict)
856
self.emailbx.encode(strio, compDict)
859
def decode(self, strio, length = None):
860
self.rmailbx, self.emailbx = Name(), Name()
861
self.rmailbx.decode(strio)
862
self.emailbx.decode(strio)
866
return hash((self.rmailbx, self.emailbx))
869
class Record_MX(tputil.FancyStrMixin, tputil.FancyEqMixin):
870
implements(IEncodable, IRecord)
873
compareAttributes = ('preference', 'name', 'ttl')
874
showAttributes = ('preference', ('name', 'name', '%s'), 'ttl')
876
def __init__(self, preference=0, name='', ttl=None, **kwargs):
877
self.preference, self.name = int(preference), Name(kwargs.get('exchange', name))
878
self.ttl = str2time(ttl)
880
def encode(self, strio, compDict = None):
881
strio.write(struct.pack('!H', self.preference))
882
self.name.encode(strio, compDict)
885
def decode(self, strio, length = None):
886
self.preference = struct.unpack('!H', readPrecisely(strio, 2))[0]
888
self.name.decode(strio)
891
warnings.warn("use Record_MX.name instead", DeprecationWarning, stacklevel=2)
894
exchange = property(exchange)
897
return hash((self.preference, self.name))
901
# Oh god, Record_TXT how I hate thee.
902
class Record_TXT(tputil.FancyEqMixin, tputil.FancyStrMixin):
903
implements(IEncodable, IRecord)
907
showAttributes = compareAttributes = ('data', 'ttl')
909
def __init__(self, *data, **kw):
910
self.data = list(data)
911
# arg man python sucks so bad
912
self.ttl = str2time(kw.get('ttl', None))
915
def encode(self, strio, compDict = None):
917
strio.write(struct.pack('!B', len(d)) + d)
920
def decode(self, strio, length = None):
923
while soFar < length:
924
L = struct.unpack('!B', readPrecisely(strio, 1))[0]
925
self.data.append(readPrecisely(strio, L))
929
"Decoded %d bytes in TXT record, but rdlength is %d" % (
936
return hash(tuple(self.data))
942
headerSize = struct.calcsize( headerFmt )
944
# Question, answer, additional, and nameserver lists
945
queries = answers = add = ns = None
947
def __init__(self, id=0, answer=0, opCode=0, recDes=0, recAv=0,
948
auth=0, rCode=OK, trunc=0, maxSize=512):
949
self.maxSize = maxSize
964
def addQuery(self, name, type=ALL_RECORDS, cls=IN):
966
Add another query to this Message.
969
@param name: The name to query.
972
@param type: Query type
975
@param cls: Query class
977
self.queries.append(Query(name, type, cls))
980
def encode(self, strio):
982
body_tmp = StringIO.StringIO()
983
for q in self.queries:
984
q.encode(body_tmp, compDict)
985
for q in self.answers:
986
q.encode(body_tmp, compDict)
987
for q in self.authority:
988
q.encode(body_tmp, compDict)
989
for q in self.additional:
990
q.encode(body_tmp, compDict)
991
body = body_tmp.getvalue()
992
size = len(body) + self.headerSize
993
if self.maxSize and size > self.maxSize:
995
body = body[:self.maxSize - self.headerSize]
996
byte3 = (( ( self.answer & 1 ) << 7 )
997
| ((self.opCode & 0xf ) << 3 )
998
| ((self.auth & 1 ) << 2 )
999
| ((self.trunc & 1 ) << 1 )
1000
| ( self.recDes & 1 ) )
1001
byte4 = ( ( (self.recAv & 1 ) << 7 )
1002
| (self.rCode & 0xf ) )
1004
strio.write(struct.pack(self.headerFmt, self.id, byte3, byte4,
1005
len(self.queries), len(self.answers),
1006
len(self.authority), len(self.additional)))
1010
def decode(self, strio, length = None):
1012
header = readPrecisely(strio, self.headerSize)
1013
r = struct.unpack(self.headerFmt, header)
1014
self.id, byte3, byte4, nqueries, nans, nns, nadd = r
1015
self.answer = ( byte3 >> 7 ) & 1
1016
self.opCode = ( byte3 >> 3 ) & 0xf
1017
self.auth = ( byte3 >> 2 ) & 1
1018
self.trunc = ( byte3 >> 1 ) & 1
1019
self.recDes = byte3 & 1
1020
self.recAv = ( byte4 >> 7 ) & 1
1021
self.rCode = byte4 & 0xf
1024
for i in range(nqueries):
1030
self.queries.append(q)
1032
items = ((self.answers, nans), (self.authority, nns), (self.additional, nadd))
1033
for (l, n) in items:
1034
self.parseRecords(l, n, strio)
1037
def parseRecords(self, list, num, strio):
1038
for i in range(num):
1041
header.decode(strio)
1044
t = self.lookupRecordType(header.type)
1047
header.payload = t(ttl=header.ttl)
1049
header.payload.decode(strio, header.rdlength)
1055
def lookupRecordType(self, type):
1056
return globals().get('Record_' + QUERY_TYPES.get(type, ''), None)
1060
strio = StringIO.StringIO()
1062
return strio.getvalue()
1065
def fromStr(self, str):
1066
strio = StringIO.StringIO(str)
1070
class DNSDatagramProtocol(protocol.DatagramProtocol):
1078
def __init__(self, controller):
1079
self.controller = controller
1080
self.id = random.randrange(2 ** 10, 2 ** 15)
1084
self.id += randomSource() % (2 ** 10)
1086
if self.id not in self.liveMessages:
1090
def stopProtocol(self):
1091
self.liveMessages = {}
1093
self.transport = None
1095
def startProtocol(self):
1096
self.liveMessages = {}
1099
def writeMessage(self, message, address):
1100
self.transport.write(message.toStr(), address)
1102
def startListening(self):
1103
from twisted.internet import reactor
1104
reactor.listenUDP(0, self, maxPacketSize=512)
1106
def datagramReceived(self, data, addr):
1111
log.msg("Truncated packet (%d bytes) from %s" % (len(data), addr))
1114
# Nothing should trigger this, but since we're potentially
1115
# invoking a lot of different decoding methods, we might as well
1116
# be extra cautious. Anything that triggers this is itself
1118
log.err(failure.Failure(), "Unexpected decoding error")
1121
if m.id in self.liveMessages:
1122
d, canceller = self.liveMessages[m.id]
1123
del self.liveMessages[m.id]
1125
# XXX we shouldn't need this hack of catching exceptioon on callback()
1131
if m.id not in self.resends:
1132
self.controller.messageReceived(m, self, addr)
1135
def removeResend(self, id):
1136
"""Mark message ID as no longer having duplication suppression."""
1138
del self.resends[id]
1142
def query(self, address, queries, timeout = 10, id = None):
1144
Send out a message with the given queries.
1146
@type address: C{tuple} of C{str} and C{int}
1147
@param address: The address to which to send the query
1149
@type queries: C{list} of C{Query} instances
1150
@param queries: The queries to transmit
1154
from twisted.internet import reactor
1156
if not self.transport:
1157
# XXX transport might not get created automatically, use callLater?
1158
self.startListening()
1163
self.resends[id] = 1
1164
m = Message(id, recDes=1)
1167
resultDeferred = defer.Deferred()
1168
cancelCall = reactor.callLater(timeout, self._clearFailed, resultDeferred, id)
1169
self.liveMessages[id] = (resultDeferred, cancelCall)
1171
self.writeMessage(m, address)
1172
return resultDeferred
1175
def _clearFailed(self, deferred, id):
1177
del self.liveMessages[id]
1180
deferred.errback(failure.Failure(DNSQueryTimeoutError(id)))
1183
class DNSProtocol(protocol.Protocol):
1192
def __init__(self, controller):
1193
self.controller = controller
1194
self.liveMessages = {}
1195
self.id = random.randrange(2 ** 10, 2 ** 15)
1200
self.id += randomSource() % (2 ** 10)
1202
if not self.liveMessages.has_key(self.id):
1207
def writeMessage(self, message):
1209
self.transport.write(struct.pack('!H', len(s)) + s)
1212
def connectionMade(self):
1213
self.controller.connectionMade(self)
1216
def dataReceived(self, data):
1217
self.buffer = self.buffer + data
1220
if self.length is None and len(self.buffer) >= 2:
1221
self.length = struct.unpack('!H', self.buffer[:2])[0]
1222
self.buffer = self.buffer[2:]
1224
if len(self.buffer) >= self.length:
1225
myChunk = self.buffer[:self.length]
1230
d = self.liveMessages[m.id]
1232
self.controller.messageReceived(m, self)
1234
del self.liveMessages[m.id]
1240
self.buffer = self.buffer[self.length:]
1247
def query(self, queries, timeout = None):
1249
Send out a message with the given queries.
1251
@type queries: C{list} of C{Query} instances
1252
@param queries: The queries to transmit
1257
d = self.liveMessages[id] = defer.Deferred()
1258
if timeout is not None:
1259
d.setTimeout(timeout)
1260
m = Message(id, recDes=1)
1262
self.writeMessage(m)
added
removed
src/twisted/names/dns.py
