a few hours of work
This commit is contained in:
parent
0e6dc0091b
commit
54ff5d65f2
1 changed files with 366 additions and 0 deletions
366
validate-my-dns.py
Normal file
366
validate-my-dns.py
Normal file
|
|
@ -0,0 +1,366 @@
|
||||||
|
#!/usr/bin/env python3
|
||||||
|
|
||||||
|
import hashlib
|
||||||
|
import base64
|
||||||
|
import struct
|
||||||
|
import sys
|
||||||
|
import os
|
||||||
|
import subprocess
|
||||||
|
import json
|
||||||
|
|
||||||
|
REGISTRY_PATH = "../registry"
|
||||||
|
|
||||||
|
# step1:
|
||||||
|
|
||||||
|
|
||||||
|
def get_domain_by_mntner(mntner):
|
||||||
|
"""get a list of domains (and reverse ipv4/6) if a nserver is specified"""
|
||||||
|
# grep for the given mntner in the dns,inetnum,inet6num directory of the registry and split it into a list; replace // with / in case REGISTRY_PATH ends with /
|
||||||
|
dns_files = subprocess.Popen(["grep", "-Ril", f" {mntner}", f"{REGISTRY_PATH}/data/dns/"],
|
||||||
|
stdout=subprocess.PIPE).communicate()[0].decode().replace("//", "/").split("\n")[:-1]
|
||||||
|
inetnums_files = subprocess.Popen(["grep", "-Ril", f" {mntner}", f"{REGISTRY_PATH}/data/inetnum/"],
|
||||||
|
stdout=subprocess.PIPE).communicate()[0].decode().replace("//", "/").split("\n")[:-1]
|
||||||
|
inet6nums_files = subprocess.Popen(
|
||||||
|
["grep", "-Ril", f" {mntner}", f"{REGISTRY_PATH}/data/inet6num/"], stdout=subprocess.PIPE).communicate()[0].decode().split("\n")[:-1]
|
||||||
|
|
||||||
|
# domains dict containing dns objects and inet(6)nums if they have nserver specified
|
||||||
|
domains = {}
|
||||||
|
# read dns files
|
||||||
|
for domain in dns_files:
|
||||||
|
with open(domain) as d:
|
||||||
|
domain_name = domain.split("/")[-1]
|
||||||
|
# a dictionary for each domain with "nserver": {"ns1.domain.dn42": ["ns1 ipv4", "ns1 ipv6"], ...}, "ds-rdata": ["123 45 67 ...", "98 7 65 ..."]
|
||||||
|
domains[domain_name] = {"nserver": {}, "ds-rdata": []}
|
||||||
|
for line in d.readlines():
|
||||||
|
line = line.replace("\n", "")
|
||||||
|
if line.startswith("nserver"):
|
||||||
|
nserver = line[20:].split(" ")
|
||||||
|
# handle edge case where
|
||||||
|
if "\t" in nserver[0]:
|
||||||
|
nserver = nserver[0].split("\t")
|
||||||
|
# ignore registry-sync nservers
|
||||||
|
if "registry-sync.dn42" in nserver[0]:
|
||||||
|
break
|
||||||
|
# nserver should be defined in an other dns file
|
||||||
|
if len(nserver) == 1:
|
||||||
|
domains[domain_name]["nserver"][nserver[0]] = None
|
||||||
|
# nserver is defined in this file
|
||||||
|
elif len(nserver) == 2:
|
||||||
|
if nserver[0] not in domains[domain_name]["nserver"]:
|
||||||
|
domains[domain_name]["nserver"][nserver[0]] = [nserver[1]]
|
||||||
|
else:
|
||||||
|
domains[domain_name]["nserver"][nserver[0]].append(nserver[1])
|
||||||
|
|
||||||
|
elif line.startswith("ds-rdata:"):
|
||||||
|
domains[domain_name]["ds-rdata"].append(line[20:])
|
||||||
|
# load inetnums
|
||||||
|
for inetnum in inetnums_files:
|
||||||
|
# temp variables in case there is no nserver
|
||||||
|
_nserver = {}
|
||||||
|
_ds_rdata = []
|
||||||
|
_domain_name = ""
|
||||||
|
with open(inetnum) as i4:
|
||||||
|
for line in i4.readlines():
|
||||||
|
line = line.replace("\n", "")
|
||||||
|
if line.startswith("cidr"):
|
||||||
|
line = line[20:]
|
||||||
|
_domain_name = ".".join(line.split(".")[::-1]) + ".in-addr.arpa"
|
||||||
|
elif line.startswith("nserver"):
|
||||||
|
nserver = line[20:].split(" ")
|
||||||
|
# handle edge case where
|
||||||
|
if "\t" in nserver[0]:
|
||||||
|
nserver = nserver[0].split("\t")
|
||||||
|
# ignore registry-sync nservers
|
||||||
|
if "registry-sync.dn42" in nserver[0]:
|
||||||
|
break
|
||||||
|
# nserver should be defined in an other dns file
|
||||||
|
if len(nserver) == 1:
|
||||||
|
_nserver[nserver[0]] = None
|
||||||
|
# nserver is defined in this file
|
||||||
|
elif len(nserver) == 2:
|
||||||
|
if nserver[0] not in _nserver:
|
||||||
|
_nserver[nserver[0]] = [nserver[1]]
|
||||||
|
else:
|
||||||
|
_nserver[nserver[0]].append(nserver[1])
|
||||||
|
|
||||||
|
elif line.startswith("ds-rdata:"):
|
||||||
|
_ds_rdata.append(line[20:])
|
||||||
|
# if nserver list is not empty add the reverse to the domain list
|
||||||
|
if not _nserver == {}:
|
||||||
|
domains[_domain_name] = {"nserver": _nserver, "ds-rdata":_ds_rdata}
|
||||||
|
# load inet6nums
|
||||||
|
for inet6num in inet6nums_files:
|
||||||
|
# temp variables in case there is no nserver
|
||||||
|
_nserver = {}
|
||||||
|
_ds_rdata = []
|
||||||
|
_domain_name = ""
|
||||||
|
with open(inet6num) as i6:
|
||||||
|
for line in i6.readlines():
|
||||||
|
line = line.replace("\n", "")
|
||||||
|
if line.startswith("inet6num"):
|
||||||
|
line = line[20:]
|
||||||
|
|
||||||
|
# generate the reverse ipv6
|
||||||
|
_domain_name = "ip6.arpa"
|
||||||
|
_lowest, _highest = line.replace(":","").split(" - ")
|
||||||
|
for _digit1, _digit2 in zip(_lowest,_highest):
|
||||||
|
if _digit1 != _digit2:
|
||||||
|
break
|
||||||
|
_domain_name = _digit1 + "." + _domain_name
|
||||||
|
elif line.startswith("nserver"):
|
||||||
|
nserver = line[20:].split(" ")
|
||||||
|
|
||||||
|
# handle edge case where
|
||||||
|
if "\t" in nserver[0]:
|
||||||
|
nserver = nserver[0].split("\t")
|
||||||
|
# ignore registry-sync nservers
|
||||||
|
if "registry-sync.dn42" in nserver[0]:
|
||||||
|
break
|
||||||
|
|
||||||
|
# nserver should be defined in an other dns file
|
||||||
|
if len(nserver) == 1:
|
||||||
|
_nserver[nserver[0]] = None
|
||||||
|
# nserver is defined in this file
|
||||||
|
elif len(nserver) == 2:
|
||||||
|
if nserver[0] not in _nserver:
|
||||||
|
_nserver[nserver[0]] = [nserver[1]]
|
||||||
|
else:
|
||||||
|
_nserver[nserver[0]].append(nserver[1])
|
||||||
|
|
||||||
|
elif line.startswith("ds-rdata:"):
|
||||||
|
_ds_rdata.append(line[20:])
|
||||||
|
# if nserver list is not empty add the reverse to the domain list
|
||||||
|
if not _nserver == {}:
|
||||||
|
domains[_domain_name] = {"nserver": _nserver, "ds-rdata":_ds_rdata}
|
||||||
|
|
||||||
|
# add entries from main domain, if the nserver doesn't have an ip address (like in inet(6)nums)
|
||||||
|
for domain in domains:
|
||||||
|
for nserver in domains[domain]["nserver"]:
|
||||||
|
# if the nserver isn't specified: ...
|
||||||
|
if domains[domain]["nserver"][nserver] == None:
|
||||||
|
#print(f"INFO: the nserver {nserver} isn't specified in {domain}, looking into the parent domain of it")
|
||||||
|
for i in range(len(nserver.split(".")), 1, -1):
|
||||||
|
# check if the nserver is already in loaded database, starts with more specific
|
||||||
|
if ".".join(nserver.split(".")[-i:]) in domains:
|
||||||
|
try:
|
||||||
|
domains[domain]["nserver"][nserver] = domains[".".join(nserver.split(".")[-i:])]["nserver"][nserver]
|
||||||
|
except KeyError:
|
||||||
|
# reaches here if the domain for the nserver specified in the inet{6}num/domain is found, but the nserver itself not.
|
||||||
|
print(f"Warn: the nserver {nserver} specified in {domain} wasn't found")
|
||||||
|
break
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
return domains
|
||||||
|
|
||||||
|
def get_dnskey(domain, nserver=None):
|
||||||
|
"""query dns server for DNSKEY"""
|
||||||
|
|
||||||
|
if not nserver:
|
||||||
|
# drill: use DNSSEC, fallback to tcp, for $domain
|
||||||
|
drill_cmd = subprocess.Popen(
|
||||||
|
["drill", "-D", "-a", "DNSKEY", domain], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
|
||||||
|
else:
|
||||||
|
# drill: use DNSSEC, fallback to tcp, ask $nserver for $domain
|
||||||
|
drill_cmd = subprocess.Popen(
|
||||||
|
["drill", "-D", "-a", "DNSKEY", f"@{nserver}", domain], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
|
||||||
|
# get the output of the drill command
|
||||||
|
lines = drill_cmd.communicate()[0].decode().split("\n")
|
||||||
|
# filter out comments (;;) and empty lines
|
||||||
|
new_lines = []
|
||||||
|
for line in lines:
|
||||||
|
if line == "" or line.startswith(";;"):
|
||||||
|
continue
|
||||||
|
new_lines.append(line)
|
||||||
|
lines = new_lines
|
||||||
|
# split records into domain and key
|
||||||
|
dnskeys = [[record.split("\t")[0], record.split("\t")[-1]]
|
||||||
|
for record in lines]
|
||||||
|
#print(len(dnskeys))
|
||||||
|
return dnskeys
|
||||||
|
# end_step1
|
||||||
|
|
||||||
|
|
||||||
|
# step 2: <start dnskey_to_DS.py based on https://gist.github.com/wido/4c6288b2f5ba6d16fce37dca3fc2cb4a >
|
||||||
|
"""
|
||||||
|
Generate a DNSSEC DS record based on the incoming DNSKEY record
|
||||||
|
The DNSKEY can be found using for example 'dig':
|
||||||
|
$ dig DNSKEY secure.widodh.nl
|
||||||
|
The output can then be parsed with the following code to generate a DS record
|
||||||
|
for in the parent DNS zone
|
||||||
|
Author: Wido den Hollander <wido@widodh.nl>
|
||||||
|
Many thanks to this blogpost: https://www.v13.gr/blog/?p=239
|
||||||
|
"""
|
||||||
|
|
||||||
|
|
||||||
|
def _calc_keyid(flags, protocol, algorithm, dnskey):
|
||||||
|
st = struct.pack('!HBB', int(flags), int(protocol), int(algorithm))
|
||||||
|
st += base64.b64decode(dnskey)
|
||||||
|
|
||||||
|
cnt = 0
|
||||||
|
for idx in range(len(st)):
|
||||||
|
s = struct.unpack('B', st[idx:idx+1])[0]
|
||||||
|
if (idx % 2) == 0:
|
||||||
|
cnt += s << 8
|
||||||
|
else:
|
||||||
|
cnt += s
|
||||||
|
|
||||||
|
return ((cnt & 0xFFFF) + (cnt >> 16)) & 0xFFFF
|
||||||
|
|
||||||
|
|
||||||
|
def _calc_ds(domain, flags, protocol, algorithm, dnskey):
|
||||||
|
if domain.endswith('.') is False:
|
||||||
|
domain += '.'
|
||||||
|
|
||||||
|
signature = bytes()
|
||||||
|
for i in domain.split('.'):
|
||||||
|
signature += struct.pack('B', len(i)) + i.encode()
|
||||||
|
|
||||||
|
signature += struct.pack('!HBB', int(flags), int(protocol), int(algorithm))
|
||||||
|
signature += base64.b64decode(dnskey)
|
||||||
|
|
||||||
|
return {
|
||||||
|
'sha1': hashlib.sha1(signature).hexdigest().upper(),
|
||||||
|
'sha256': hashlib.sha256(signature).hexdigest().upper(),
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
def dnskey_to_ds(domain, dnskey):
|
||||||
|
dnskeylist = dnskey.split(' ', 3)
|
||||||
|
|
||||||
|
flags = dnskeylist[0]
|
||||||
|
protocol = dnskeylist[1]
|
||||||
|
algorithm = dnskeylist[2]
|
||||||
|
key = dnskeylist[3].replace(' ', '')
|
||||||
|
|
||||||
|
keyid = _calc_keyid(flags, protocol, algorithm, key)
|
||||||
|
ds = _calc_ds(domain, flags, protocol, algorithm, key)
|
||||||
|
|
||||||
|
ret = list()
|
||||||
|
ret.append(str(keyid) + ' ' + str(algorithm) + ' ' + str(1) + ' '
|
||||||
|
+ ds['sha1'].lower())
|
||||||
|
ret.append(str(keyid) + ' ' + str(algorithm) + ' ' + str(2) + ' '
|
||||||
|
+ ds['sha256'].lower())
|
||||||
|
return ret
|
||||||
|
|
||||||
|
# if __name__ == "__main__":
|
||||||
|
# print(len(sys.argv))
|
||||||
|
# if len(sys.argv) == 1:
|
||||||
|
# print("no data specified, please enter manually")
|
||||||
|
# DOMAIN = input("enter domain: ")
|
||||||
|
# DNSKEY = input("enter DNSKEY: ")
|
||||||
|
#
|
||||||
|
# print(dnskey_to_ds(DOMAIN, DNSKEY))
|
||||||
|
# elif len(sys.argv) in [9,10]:
|
||||||
|
# # user pasted full dig output
|
||||||
|
# DOMAIN = sys.argv[1]
|
||||||
|
# DNSKEY = " ".join(sys.argv[5:])
|
||||||
|
# print(DOMAIN)
|
||||||
|
# print(DNSKEY)
|
||||||
|
# print(dnskey_to_ds(DOMAIN,DNSKEY))
|
||||||
|
|
||||||
|
# step2: <end dnskey_to_DS.py>
|
||||||
|
|
||||||
|
# step3: start: partially stolen from: https://stackoverflow.com/questions/26137036/programmatically-check-if-domains-are-dnssec-protected
|
||||||
|
|
||||||
|
def check_dnssec(domain_name, domain_data):
|
||||||
|
import dns.name
|
||||||
|
import dns.query
|
||||||
|
import dns.dnssec
|
||||||
|
import dns.message
|
||||||
|
import dns.resolver
|
||||||
|
import dns.rdatatype
|
||||||
|
import dns.exception
|
||||||
|
|
||||||
|
success = False
|
||||||
|
|
||||||
|
no_ds_rdata = domain_data["ds-rdata"] == []
|
||||||
|
if no_ds_rdata:
|
||||||
|
print(f"INFO: {domain_name} doesn't have ds-rdata configured, not checking it")
|
||||||
|
|
||||||
|
for nserver in domain_data["nserver"]:
|
||||||
|
|
||||||
|
# if the nserver is not set (i.e. not loaded from other dns file or "wrong" fqdn)
|
||||||
|
if domain_data["nserver"][nserver] == None:
|
||||||
|
print(f"INFO: ip address(es) for nserver '{nserver}' in '{domain_name}' isn't specified/loaded")
|
||||||
|
continue
|
||||||
|
for nsaddr in domain_data["nserver"][nserver]:
|
||||||
|
|
||||||
|
# get SOA
|
||||||
|
request = dns.message.make_query(domain_name, dns.rdatatype.SOA,want_dnssec=False)
|
||||||
|
try:
|
||||||
|
# send the query
|
||||||
|
dns.query.udp(request,nsaddr, timeout=2)
|
||||||
|
# if it timed out: tell the user
|
||||||
|
except dns.exception.Timeout:
|
||||||
|
print(f"WARN: querying {nserver} ({nsaddr}) for {domain_name} timed out")
|
||||||
|
continue
|
||||||
|
|
||||||
|
if no_ds_rdata:
|
||||||
|
print(f"INFO: query for {domain_name} SOA on {nserver} ({nsaddr}) succeded, not checking DNSSEC")
|
||||||
|
continue
|
||||||
|
# get DNSKEY for zone
|
||||||
|
request = dns.message.make_query(domain_name, dns.rdatatype.DNSKEY,want_dnssec=True)
|
||||||
|
response = dns.query.udp(request,nsaddr, timeout=2)
|
||||||
|
|
||||||
|
if response.rcode() != 0:
|
||||||
|
# HANDLE QUERY FAILED (SERVER ERROR OR NO DNSKEY RECORD)
|
||||||
|
print(f"WARN: query for a DNSKEY on {domain_name} failed on {nserver} ({nsaddr}), returncode: {response.rcode()}")
|
||||||
|
continue
|
||||||
|
# answer should contain two RRSET: DNSKEY and RRSIG(DNSKEY)
|
||||||
|
answer = response.answer
|
||||||
|
if len(answer) != 2:
|
||||||
|
# SOMETHING WENT WRONG
|
||||||
|
print(f"ERROR: query for a DNSKEY on {domain_name} failed on {nserver} ({nsaddr}), invalid answer length: {len(answer)}")
|
||||||
|
continue
|
||||||
|
# the DNSKEY should be self signed, validate it
|
||||||
|
name = dns.name.from_text(domain_name)
|
||||||
|
try:
|
||||||
|
#print(f"DEBUG: answer[0]: {answer[0]}")
|
||||||
|
#print(f"DEBUG: answer[1]: {answer[1]}")
|
||||||
|
try:
|
||||||
|
dns.dnssec.validate(answer[0],answer[1],{name:answer[0]})
|
||||||
|
# it raises an AttributeError if the records are in the wrong order
|
||||||
|
except AttributeError as e:
|
||||||
|
dns.dnssec.validate(answer[1],answer[0],{name:answer[0]})
|
||||||
|
|
||||||
|
except dns.dnssec.ValidationFailure:
|
||||||
|
# BE SUSPICIOUS
|
||||||
|
print(f"WARN: DNSSEC validation failed on {domain_name} failed on {nserver} ({nsaddr}), answer: {answer}")
|
||||||
|
except AttributeError as e:
|
||||||
|
print(f"ERROR: {e}")
|
||||||
|
else:
|
||||||
|
# WE'RE GOOD, THERE'S A VALID DNSSEC SELF-SIGNED KEY FOR example.com
|
||||||
|
print(f"INFO: DNSSEC validation succeded on {domain_name} failed on {nserver} ({nsaddr})")
|
||||||
|
success = True
|
||||||
|
|
||||||
|
return success
|
||||||
|
|
||||||
|
|
||||||
|
# step3: end
|
||||||
|
|
||||||
|
def main(mntner):
|
||||||
|
|
||||||
|
domains = get_domain_by_mntner(mntner=mntner)
|
||||||
|
|
||||||
|
#with open("domains.tmp", "w") as domain_file:
|
||||||
|
# json.dump(domains, domain_file, indent=4)
|
||||||
|
# print(domains)
|
||||||
|
|
||||||
|
for domain_name in domains:
|
||||||
|
print(check_dnssec(domain_name, domains[domain_name]))
|
||||||
|
|
||||||
|
if __name__ == "__main__":
|
||||||
|
if len(sys.argv) == 1:
|
||||||
|
print(f"please specify your mntner\n {sys.argv[0]} YOU-MNT")
|
||||||
|
exit(1)
|
||||||
|
main(sys.argv[1])
|
||||||
|
|
||||||
|
|
||||||
|
# commands to run:
|
||||||
|
# 1. drill -D <domain>.dn42 @ns1.<domain>.dn42 NS
|
||||||
|
# 2. dnskey_to_ds("<domain>.dn42"
|
||||||
|
# #<TTL> IN DNSKEY
|
||||||
|
# "257 3 13 <base64 ...>")
|
||||||
|
# 3. write dnskey to "trust-anchor"
|
||||||
|
# 4.delv @ns1.<domain.dn42 +root=<domain>.dn42 -a ./trust-anchor.tmp SOA <domain>.dn42
|
||||||
Loading…
Add table
Reference in a new issue