How make dns queries in dns-python as dig (with additional records section)?

tbicr picture tbicr · Jul 16, 2013 · Viewed 22k times · Source

I trying use dns python and want get all records with ANY type query:

import dns.name
import dns.message
import dns.query

domain = 'google.com'
name_server = '8.8.8.8'

domain = dns.name.from_text(domain)
if not domain.is_absolute():
    domain = domain.concatenate(dns.name.root)

request = dns.message.make_query(domain, dns.rdatatype.ANY)

response = dns.query.udp(request, name_server)
print response.answer
print response.additional
print response.authority

but it return me

[]
[]
[]

When I try make this request with dig:

$ dig @8.8.8.8  google.com -t ANY

; <<>> DiG 9.9.2-P1 <<>> @8.8.8.8 google.com -t ANY
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2848
;; flags: qr rd ra; QUERY: 1, ANSWER: 25, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;google.com.            IN  ANY

;; ANSWER SECTION:
google.com.     299 IN  A   173.194.40.14
google.com.     299 IN  A   173.194.40.1
google.com.     299 IN  A   173.194.40.7
google.com.     299 IN  A   173.194.40.4
google.com.     299 IN  A   173.194.40.3
google.com.     299 IN  A   173.194.40.0
google.com.     299 IN  A   173.194.40.8
google.com.     299 IN  A   173.194.40.6
google.com.     299 IN  A   173.194.40.5
google.com.     299 IN  A   173.194.40.2
google.com.     299 IN  A   173.194.40.9
google.com.     299 IN  AAAA    2a00:1450:4002:804::1000
google.com.     21599   IN  TYPE257 \# 23 0009697373756577696C6473796D616E7465632E636F6D
google.com.     21599   IN  TYPE257 \# 19 0005697373756573796D616E7465632E636F6D
google.com.     21599   IN  NS  ns2.google.com.
google.com.     21599   IN  NS  ns3.google.com.
google.com.     599 IN  MX  50 alt4.aspmx.l.google.com.
google.com.     599 IN  MX  10 aspmx.l.google.com.
google.com.     3599    IN  TXT "v=spf1 include:_spf.google.com ip4:216.73.93.70/31 ip4:216.73.93.72/31 ~all"
google.com.     599 IN  MX  20 alt1.aspmx.l.google.com.
google.com.     21599   IN  SOA ns1.google.com. dns-admin.google.com. 2013070800 7200 1800 1209600 300
google.com.     599 IN  MX  30 alt2.aspmx.l.google.com.
google.com.     21599   IN  NS  ns1.google.com.
google.com.     599 IN  MX  40 alt3.aspmx.l.google.com.
google.com.     21599   IN  NS  ns4.google.com.

;; Query time: 52 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Tue Jul 16 18:23:46 2013
;; MSG SIZE  rcvd: 623

When I check requests with wireshark then found that dig and dns python have different requests:

dig:

0000  c8 64 c7 3a e3 40 50 46  5d a5 70 99 08 00 45 00   .d.:.@PF ].p...E.
0010  00 43 9f 60 00 00 40 11  09 8f c0 a8 01 03 08 08   .C.`..@. ........
0020  08 08 8e 9e 00 35 00 2f  71 cf ef 49 01 20 00 01   .....5./ q..I. ..
0030  00 00 00 00 00 01 06 67  6f 6f 67 6c 65 03 63 6f   .......g oogle.co
0040  6d 00 00 ff 00 01 00 00  29 10 00 00 00 00 00 00   m....... ).......
0050  00                

dns python:

0000  c8 64 c7 3a e3 40 50 46  5d a5 70 99 08 00 45 00   .d.:.@PF ].p...E.
0010  00 38 00 00 40 00 40 11  68 fa c0 a8 01 03 08 08   .8..@.@. h.......
0020  08 08 b8 62 00 35 00 24  23 6b 3d 31 01 00 00 01   ...b.5.$ #k=1....
0030  00 00 00 00 00 00 06 67  6f 6f 67 6c 65 03 63 6f   .......g oogle.co
0040  6d 00 00 ff 00 01                                  m.....           

For DNS query section:

dig have AD bit: Set flag:

002C-002D: 01 20 for dig and 01 00 for dns python

and this Additional records section that except for dns-python:

0046-0050: 00 00 29 10 00 00 00 00 00 00 00.

This actual also not only for google.com also for logitech.com mayby other.

So how can I make requests with dns python as dig with this additional section?

Answer

tbicr picture tbicr · Jul 17, 2013

I found solution, I made request as dig:

import dns.name
import dns.message
import dns.query
import dns.flags

domain = 'google.com'
name_server = '8.8.8.8'
ADDITIONAL_RDCLASS = 65535

domain = dns.name.from_text(domain)
if not domain.is_absolute():
    domain = domain.concatenate(dns.name.root)

request = dns.message.make_query(domain, dns.rdatatype.ANY)
request.flags |= dns.flags.AD
request.find_rrset(request.additional, dns.name.root, ADDITIONAL_RDCLASS,
                   dns.rdatatype.OPT, create=True, force_unique=True)
response = dns.query.udp(request, name_server)


print response.answer
print response.additional
print response.authority

With ADDITIONAL_RDCLASS = 4096 like dig all work too, but I set it full to be on the safe side.

and it works pretty good.