def print_errors(errors):
for err, err_data in errors:
if err == 'Question':
print("Question error:")
for (d1, d2) in err_data:
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
elif err == 'Reply':
print("Reply error:")
for (d1, d2) in err_data:
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
elif err == 'Question Pack':
print("Question pack error")
print("QDATA:", binascii.hexlify(err_data[0]))
print(DNSRecord.parse(err_data[0]))
print("QPACK:", binascii.hexlify(err_data[1]))
print(DNSRecord.parse(err_data[1]))
elif err == 'Reply Pack':
print("Response pack error")
print("RDATA:", binascii.hexlify(err_data[0]))
print(DNSRecord.parse(err_data[0]))
print("RPACK:", binascii.hexlify(err_data[1]))
print(DNSRecord.parse(err_data[1]))
def check_decode(f, debug=False):
errors = []
# Parse the q/a records
with open(f) as x:
q, r = DigParser(x)
# Grab the hex data
with open(f, 'rb') as x:
for l in x.readlines():
if l.startswith(b';; QUERY:'):
qdata = binascii.unhexlify(l.split()[-1])
elif l.startswith(b';; RESPONSE:'):
rdata = binascii.unhexlify(l.split()[-1])
# Parse the hex data
qparse = DNSRecord.parse(qdata)
rparse = DNSRecord.parse(rdata)
# Check records generated from DiG input matches
# records parsed from packet data
if q != qparse:
errors.append(('Question', q.diff(qparse)))
if r != rparse:
errors.append(('Reply', r.diff(rparse)))
# Repack the data
qpack = qparse.pack()
rpack = rparse.pack()
# Check if repacked question data matches original
# We occasionally get issues where original packet did not
# compress all labels - in this case we reparse packed
# record, repack this and compare with the packed data
if qpack != qdata:
if len(qpack) < len(qdata):
# Shorter - possibly compression difference
if DNSRecord.parse(qpack).pack() != qpack:
errors.append(('Question Pack', (qdata, qpack)))
else:
errors.append(('Question Pack', (qdata, qpack)))
if rpack != rdata:
if len(rpack) < len(rdata):
if DNSRecord.parse(rpack).pack() != rpack:
errors.append(('Reply Pack', (rdata, rpack)))
else:
errors.append(('Reply Pack', (rdata, rpack)))
if debug:
if errors:
print("ERROR\n")
print_errors(errors)
print()
if input(">>> Inspect [y/n]? ").lower().startswith('y'):
code.interact(local=locals())
print()
else:
print("OK")
return errors
def print_errors(errors):
for err, err_data in errors:
if err == "Question":
print("Question error:")
for (d1, d2) in err_data:
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
elif err == "Reply":
print("Reply error:")
for (d1, d2) in err_data:
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
elif err == "Question Pack":
print("Question pack error")
print("QDATA:", binascii.hexlify(err_data[0]))
print(DNSRecord.parse(err_data[0]))
print("QPACK:", binascii.hexlify(err_data[1]))
print(DNSRecord.parse(err_data[1]))
elif err == "Reply Pack":
print("Response pack error")
print("RDATA:", binascii.hexlify(err_data[0]))
print(DNSRecord.parse(err_data[0]))
print("RPACK:", binascii.hexlify(err_data[1]))
print(DNSRecord.parse(err_data[1]))
def check_decode(f, debug=False):
errors = []
# Parse the q/a records
with open(f) as x:
q, r = DigParser(x)
# Grab the hex data
with open(f, "rb") as x:
for l in x.readlines():
if l.startswith(b";; QUERY:"):
qdata = binascii.unhexlify(l.split()[-1])
elif l.startswith(b";; RESPONSE:"):
rdata = binascii.unhexlify(l.split()[-1])
# Parse the hex data
qparse = DNSRecord.parse(qdata)
rparse = DNSRecord.parse(rdata)
# Check records generated from DiG input matches
# records parsed from packet data
if q != qparse:
errors.append(("Question", q.diff(qparse)))
if r != rparse:
errors.append(("Reply", r.diff(rparse)))
# Repack the data
qpack = qparse.pack()
rpack = rparse.pack()
# Check if repacked question data matches original
# We occasionally get issues where original packet did not
# compress all labels - in this case we reparse packed
# record, repack this and compare with the packed data
if qpack != qdata:
if len(qpack) < len(qdata):
# Shorter - possibly compression difference
if DNSRecord.parse(qpack).pack() != qpack:
errors.append(("Question Pack", (qdata, qpack)))
else:
errors.append(("Question Pack", (qdata, qpack)))
if rpack != rdata:
if len(rpack) < len(rdata):
if DNSRecord.parse(rpack).pack() != rpack:
errors.append(("Reply Pack", (rdata, rpack)))
else:
errors.append(("Reply Pack", (rdata, rpack)))
if debug:
if errors:
print("ERROR\n")
print_errors(errors)
print()
if input(">>> Inspect [y/n]? ").lower().startswith("y"):
code.interact(local=locals())
print()
else:
print("OK")
return errors
def parse(self):
dns = None
section = None
paren = False
rr = []
try:
while True:
tok, val = next(self.i)
if tok == 'COMMENT':
if 'Sending:' in val or 'Got answer:' in val:
if dns:
self.parseQuestions(q, dns)
self.parseAnswers(a, auth, ar, dns)
yield (dns)
dns = DNSRecord()
q, a, auth, ar = [], [], [], []
elif val.startswith('; ->>HEADER<<-'):
self.expect('NL')
val2 = self.expect('COMMENT')
dns.header = self.parseHeader(val, val2)
elif val.startswith('; QUESTION'):
section = q
elif val.startswith('; ANSWER'):
section = a
elif val.startswith('; AUTHORITY'):
section = auth
elif val.startswith('; ADDITIONAL'):
section = ar
elif val.startswith(';') or tok[1].startswith('<<>>'):
pass
elif dns and section == q:
q.append(val.split())
elif tok == 'ATOM':
if val == '(':
paren = True
elif val == ')':
paren = False
else:
rr.append(val)
elif tok == 'NL' and not paren and rr:
if self.debug:
print(">>", rr)
section.append(rr)
rr = []
except StopIteration:
if rr:
self.section.append(rr)
if dns:
self.parseQuestions(q, dns)
self.parseAnswers(a, auth, ar, dns)
yield (dns)
def parse(self):
dns = None
section = None
paren = False
rr = []
try:
while True:
tok,val = next(self.i)
if tok == 'COMMENT':
if 'Sending:' in val or 'Got answer:' in val:
if dns:
self.parseQuestions(q,dns)
self.parseAnswers(a,auth,ar,dns)
yield(dns)
dns = DNSRecord()
q,a,auth,ar = [],[],[],[]
elif val.startswith('; ->>HEADER<<-'):
self.expect('NL')
val2 = self.expect('COMMENT')
dns.header = self.parseHeader(val,val2)
elif val.startswith('; QUESTION'):
section = q
elif val.startswith('; ANSWER'):
section = a
elif val.startswith('; AUTHORITY'):
section = auth
elif val.startswith('; ADDITIONAL'):
section = ar
elif val.startswith(';') or tok[1].startswith('<<>>'):
pass
elif dns and section == q:
q.append(val.split())
elif tok == 'ATOM':
if val == '(':
paren = True
elif val == ')':
paren = False
else:
rr.append(val)
elif tok == 'NL' and not paren and rr:
if self.debug:
print(">>",rr)
section.append(rr)
rr = []
except StopIteration:
if rr:
self.section.append(rr)
if dns:
self.parseQuestions(q,dns)
self.parseAnswers(a,auth,ar,dns)
yield(dns)
def new_test(domain, qtype, address="8.8.8.8", port=53, nodig=False):
tcp = False
q = DNSRecord.question(domain, qtype)
a_pkt = q.send(address, port)
a = DNSRecord.parse(a_pkt)
if a.header.tc:
tcp = True
a_pkt = q.send(address, port, tcp)
a = DNSRecord.parse(a_pkt)
if not nodig:
dig = getoutput("dig +qr -p %d %s %s @%s" %
(port, domain, qtype, address))
dig_reply = list(iter(DigParser(dig)))
# DiG might have retried in TCP mode so get last q/a
q_dig = dig_reply[-2]
a_dig = dig_reply[-1]
if q != q_dig or a != a_dig:
if q != q_dig:
print(";;; ERROR: Diff Question differs")
for (d1, d2) in q.diff(q_dig):
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
if a != a_dig:
print(";;; ERROR: Diff Response differs")
for (d1, d2) in a.diff(a_dig):
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
return
print("Writing test file: %s-%s" % (domain, qtype))
with open("%s-%s" % (domain, qtype), "w") as f:
print(";; Sending:", file=f)
print(";; QUERY:", binascii.hexlify(q.pack()).decode(), file=f)
print(q, file=f)
print(file=f)
print(";; Got answer:", file=f)
print(";; RESPONSE:", binascii.hexlify(a_pkt).decode(), file=f)
print(a, file=f)
print(file=f)
def new_test(domain, qtype, address="8.8.8.8", port=53, nodig=False):
tcp = False
q = DNSRecord.question(domain, qtype)
a_pkt = q.send(address, port)
a = DNSRecord.parse(a_pkt)
if a.header.tc:
tcp = True
a_pkt = q.send(address, port, tcp)
a = DNSRecord.parse(a_pkt)
if not nodig:
dig = getoutput("dig +qr -p %d %s %s @%s" % (port, domain, qtype, address))
dig_reply = list(iter(DigParser(dig)))
# DiG might have retried in TCP mode so get last q/a
q_dig = dig_reply[-2]
a_dig = dig_reply[-1]
if q != q_dig or a != a_dig:
if q != q_dig:
print(";;; ERROR: Diff Question differs")
for (d1, d2) in q.diff(q_dig):
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
if a != a_dig:
print(";;; ERROR: Diff Response differs")
for (d1, d2) in a.diff(a_dig):
if d1:
print(";; - %s" % d1)
if d2:
print(";; + %s" % d2)
return
print("Writing test file: %s-%s" % (domain, qtype))
with open("%s-%s" % (domain, qtype), "w") as f:
print(";; Sending:", file=f)
print(";; QUERY:", binascii.hexlify(q.pack()).decode(), file=f)
print(q, file=f)
print(file=f)
print(";; Got answer:", file=f)
print(";; RESPONSE:", binascii.hexlify(a_pkt).decode(), file=f)
print(a, file=f)
print(file=f)
p.add_argument("--diff",default="",
help="Compare response from alternate nameserver (format: address:port / default: false)")
p.add_argument("--dig",action='store_true',default=False,
help="Compare result with DiG - if ---diff also specified use alternative nameserver for DiG request (default: false)")
p.add_argument("--short",action='store_true',default=False,
help="Short output - rdata only (default: false)")
p.add_argument("--debug",action='store_true',default=False,
help="Drop into CLI after request (default: false)")
p.add_argument("domain",metavar="<domain>",
help="Query domain")
p.add_argument("qtype",metavar="<type>",default="A",nargs="?",
help="Query type (default: A)")
args = p.parse_args()
# Construct request
q = DNSRecord(q=DNSQuestion(args.domain,getattr(QTYPE,args.qtype)))
address,_,port = args.server.partition(':')
port = int(port or 53)
if args.query:
print(";; Sending%s:" % (" (TCP)" if args.tcp else ""))
if args.hex:
print(";; QUERY:",binascii.hexlify(q.pack()).decode())
print(q)
print()
a_pkt = q.send(address,port,tcp=args.tcp)
a = DNSRecord.parse(a_pkt)
if a.header.tc and args.noretry == False:
default=False,
help="Short output - rdata only (default: false)")
p.add_argument("--debug",
action='store_true',
default=False,
help="Drop into CLI after request (default: false)")
p.add_argument("domain", metavar="<domain>", help="Query domain")
p.add_argument("qtype",
metavar="<type>",
default="A",
nargs="?",
help="Query type (default: A)")
args = p.parse_args()
# Construct request
q = DNSRecord(q=DNSQuestion(args.domain, getattr(QTYPE, args.qtype)))
address, _, port = args.server.partition(':')
port = int(port or 53)
if args.query:
print(";; Sending%s:" % (" (TCP)" if args.tcp else ""))
if args.hex:
print(";; QUERY:", binascii.hexlify(q.pack()).decode())
print(q)
print()
a_pkt = q.send(address, port, tcp=args.tcp)
a = DNSRecord.parse(a_pkt)
if a.header.tc and args.noretry == False:
