stevazi/addon
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 3 Wiki Activity

Revert "(experimental) force to use custom dns"

Browse Source 
This reverts commit 2a6a5e62d4.
This commit is contained in:
mac12m99
2019-04-28 18:11:11 +02:00
parent 2a6a5e62d4
commit 1747bc98db
100 changed files with 2 additions and 15717 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/dns/renderer.py
-291
View File
@@ -1,291 +0,0 @@
# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2001-2017 Nominum, Inc.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
"""Help for building DNS wire format messages"""
from io import BytesIO
import struct
import random
import time
import dns.exception
import dns.tsig
from ._compat import long
QUESTION = 0
ANSWER = 1
AUTHORITY = 2
ADDITIONAL = 3
class Renderer(object):
"""Helper class for building DNS wire-format messages.
Most applications can use the higher-level L{dns.message.Message}
class and its to_wire() method to generate wire-format messages.
This class is for those applications which need finer control
over the generation of messages.
Typical use::
r = dns.renderer.Renderer(id=1, flags=0x80, max_size=512)
r.add_question(qname, qtype, qclass)
r.add_rrset(dns.renderer.ANSWER, rrset_1)
r.add_rrset(dns.renderer.ANSWER, rrset_2)
r.add_rrset(dns.renderer.AUTHORITY, ns_rrset)
r.add_edns(0, 0, 4096)
r.add_rrset(dns.renderer.ADDTIONAL, ad_rrset_1)
r.add_rrset(dns.renderer.ADDTIONAL, ad_rrset_2)
r.write_header()
r.add_tsig(keyname, secret, 300, 1, 0, '', request_mac)
wire = r.get_wire()
output, a BytesIO, where rendering is written
id: the message id
flags: the message flags
max_size: the maximum size of the message
origin: the origin to use when rendering relative names
compress: the compression table
section: an int, the section currently being rendered
counts: list of the number of RRs in each section
mac: the MAC of the rendered message (if TSIG was used)
"""
def __init__(self, id=None, flags=0, max_size=65535, origin=None):
"""Initialize a new renderer."""
self.output = BytesIO()
if id is None:
self.id = random.randint(0, 65535)
else:
self.id = id
self.flags = flags
self.max_size = max_size
self.origin = origin
self.compress = {}
self.section = QUESTION
self.counts = [0, 0, 0, 0]
self.output.write(b'\x00' * 12)
self.mac = ''
def _rollback(self, where):
"""Truncate the output buffer at offset *where*, and remove any
compression table entries that pointed beyond the truncation
point.
"""
self.output.seek(where)
self.output.truncate()
keys_to_delete = []
for k, v in self.compress.items():
if v >= where:
keys_to_delete.append(k)
for k in keys_to_delete:
del self.compress[k]
def _set_section(self, section):
"""Set the renderer's current section.
Sections must be rendered order: QUESTION, ANSWER, AUTHORITY,
ADDITIONAL. Sections may be empty.
Raises dns.exception.FormError if an attempt was made to set
a section value less than the current section.
"""
if self.section != section:
if self.section > section:
raise dns.exception.FormError
self.section = section
def add_question(self, qname, rdtype, rdclass=dns.rdataclass.IN):
"""Add a question to the message."""
self._set_section(QUESTION)
before = self.output.tell()
qname.to_wire(self.output, self.compress, self.origin)
self.output.write(struct.pack("!HH", rdtype, rdclass))
after = self.output.tell()
if after >= self.max_size:
self._rollback(before)
raise dns.exception.TooBig
self.counts[QUESTION] += 1
def add_rrset(self, section, rrset, **kw):
"""Add the rrset to the specified section.
Any keyword arguments are passed on to the rdataset's to_wire()
routine.
"""
self._set_section(section)
before = self.output.tell()
n = rrset.to_wire(self.output, self.compress, self.origin, **kw)
after = self.output.tell()
if after >= self.max_size:
self._rollback(before)
raise dns.exception.TooBig
self.counts[section] += n
def add_rdataset(self, section, name, rdataset, **kw):
"""Add the rdataset to the specified section, using the specified
name as the owner name.
Any keyword arguments are passed on to the rdataset's to_wire()
routine.
"""
self._set_section(section)
before = self.output.tell()
n = rdataset.to_wire(name, self.output, self.compress, self.origin,
**kw)
after = self.output.tell()
if after >= self.max_size:
self._rollback(before)
raise dns.exception.TooBig
self.counts[section] += n
def add_edns(self, edns, ednsflags, payload, options=None):
"""Add an EDNS OPT record to the message."""
# make sure the EDNS version in ednsflags agrees with edns
ednsflags &= long(0xFF00FFFF)
ednsflags |= (edns << 16)
self._set_section(ADDITIONAL)
before = self.output.tell()
self.output.write(struct.pack('!BHHIH', 0, dns.rdatatype.OPT, payload,
ednsflags, 0))
if options is not None:
lstart = self.output.tell()
for opt in options:
stuff = struct.pack("!HH", opt.otype, 0)
self.output.write(stuff)
start = self.output.tell()
opt.to_wire(self.output)
end = self.output.tell()
assert end - start < 65536
self.output.seek(start - 2)
stuff = struct.pack("!H", end - start)
self.output.write(stuff)
self.output.seek(0, 2)
lend = self.output.tell()
assert lend - lstart < 65536
self.output.seek(lstart - 2)
stuff = struct.pack("!H", lend - lstart)
self.output.write(stuff)
self.output.seek(0, 2)
after = self.output.tell()
if after >= self.max_size:
self._rollback(before)
raise dns.exception.TooBig
self.counts[ADDITIONAL] += 1
def add_tsig(self, keyname, secret, fudge, id, tsig_error, other_data,
request_mac, algorithm=dns.tsig.default_algorithm):
"""Add a TSIG signature to the message."""
s = self.output.getvalue()
(tsig_rdata, self.mac, ctx) = dns.tsig.sign(s,
keyname,
secret,
int(time.time()),
fudge,
id,
tsig_error,
other_data,
request_mac,
algorithm=algorithm)
self._write_tsig(tsig_rdata, keyname)
def add_multi_tsig(self, ctx, keyname, secret, fudge, id, tsig_error,
other_data, request_mac,
algorithm=dns.tsig.default_algorithm):
"""Add a TSIG signature to the message. Unlike add_tsig(), this can be
used for a series of consecutive DNS envelopes, e.g. for a zone
transfer over TCP [RFC2845, 4.4].
For the first message in the sequence, give ctx=None. For each
subsequent message, give the ctx that was returned from the
add_multi_tsig() call for the previous message."""
s = self.output.getvalue()
(tsig_rdata, self.mac, ctx) = dns.tsig.sign(s,
keyname,
secret,
int(time.time()),
fudge,
id,
tsig_error,
other_data,
request_mac,
ctx=ctx,
first=ctx is None,
multi=True,
algorithm=algorithm)
self._write_tsig(tsig_rdata, keyname)
return ctx
def _write_tsig(self, tsig_rdata, keyname):
self._set_section(ADDITIONAL)
before = self.output.tell()
keyname.to_wire(self.output, self.compress, self.origin)
self.output.write(struct.pack('!HHIH', dns.rdatatype.TSIG,
dns.rdataclass.ANY, 0, 0))
rdata_start = self.output.tell()
self.output.write(tsig_rdata)
after = self.output.tell()
assert after - rdata_start < 65536
if after >= self.max_size:
self._rollback(before)
raise dns.exception.TooBig
self.output.seek(rdata_start - 2)
self.output.write(struct.pack('!H', after - rdata_start))
self.counts[ADDITIONAL] += 1
self.output.seek(10)
self.output.write(struct.pack('!H', self.counts[ADDITIONAL]))
self.output.seek(0, 2)
def write_header(self):
"""Write the DNS message header.
Writing the DNS message header is done after all sections
have been rendered, but before the optional TSIG signature
is added.
"""
self.output.seek(0)
self.output.write(struct.pack('!HHHHHH', self.id, self.flags,
self.counts[0], self.counts[1],
self.counts[2], self.counts[3]))
self.output.seek(0, 2)
def get_wire(self):
"""Return the wire format message."""
return self.output.getvalue()