CL_RFC2671_5_3_OPT_not_understand - Responders don't understand OPT RR
Verify that a NUT retransmits query when responders don't understand OPT RR
- Responders who do not understand these protocol extensions are
- expected to send a response with RCODE NOTIMPL, FORMERR, or SERVFAIL.
- Therefore use of extensions should be "probed" such that a responder
- who isn't known to support them be allowed a retry with no extensions
- if it responds with such an RCODE.
Client
CL_RFC2671_5_3_OPT_not_understand.seq [-tooloption ...]: KOI tool option
See also DNSConfig.pm
AP Server1(TN):A.example.com DNS Server1(TN)
|3ffe:501:ffff:101::10 |3ffe:501:ffff:101::20
|192.168.1.10 |192.168.1.20
| |
Net-y --+--------+-----------------------+-------- 3ffe:501:ffff:101::/64
| 192.168.1/24
|
|
ROUTER1(TN)
|3ffe:501:ffff:100::1
|192.168.0.1
|
Net-z --+--------+-------------------------------- 3ffe:501:ffff:100::/64
| 192.168.0/24
DNS Client1(NUT)
3ffe:501:ffff:100:XXXX
192.168.0.10
XXXX: EUI64 address
Setup
Set the DNS Server1(TN)'s address on NUT as above mentioned Network Topology.
Pre-Sequence
In order to send the query for A type of AP Server1(TN):A.example.com
to the DNS Server1(TN) with OPT RR(1024 bytes), NUT is configured.
This test sequence is following.
DNS Client1 (NUT) DNS Server1 (TN)
| |
|--------------------------------------------->|
| 1. Send standard query |
| with OPT RR |
| |
|<---------------------------------------------|
| 2. Send query response |
| RCODE=4(Not Implemented) |
| |
|--------------------------------------------->|
| 3. Send standard query |
| without OPT RR |
| |
v v
1. NUT send standard query with OPT RR to TN.
Judgment (Check *1)
2. TN send standard query response to NUT.
3. NUT send standard query to TN.*Send query automatically.
Judgment (Check *3)
Packet Description
1st Packet.
|
1. Standard query from DNS Client1 (NUT) to DNS Server1 (TN)
|
| IP Header |
Source Address |
NUT_NETZ |
| Destination Address |
SV_NETY |
| UDP Header |
Src Port |
any |
| Dst Port |
53 |
| DNS Header |
ID |
any |
| QR |
0 |
| OPCODE |
0 |
| AA |
any |
| TC |
0 |
| RD |
any |
| RA |
any |
| Z |
any |
| RCODE |
any |
| QDCOUNT |
1 |
| ANCOUNT |
1 |
| NSCOUNT |
0 |
| ARCOUNT |
any |
| DNS Question section |
QNAME |
A.example.com |
| QTYPE |
A (0x0001) |
| QCLASS |
any |
| DNS Additional section |
NAME(root) |
empty (root domain 0x00) |
| TYPE(OPT) |
EDNS0 option(0x0029) |
| CLASS(UDP payload size) |
0x0400 |
| TTL(EXTENDED-RCODE) |
0x00 |
| TTL(VERSION) |
0x00 |
| TTL(Z) |
0x0000 |
| RDLENGTH (describes RDATA) |
0x0 |
| RDATA {attribute,value} pairs |
empty |
2nd packet.
|
2. Standard query response from DNS Server1 (TN) to Client1 (NUT)
|
| IP Header |
Source Address |
SV_NETY |
| Destination Address |
NUT_NETZ |
| UDP Header |
Src Port |
53 |
| Dst Port |
Same as 1st Packet's Src Port |
| DNS Header |
ID |
Same as 1st Packet's ID |
| QR |
1 |
| OPCODE |
0 |
| AA |
0 |
| TC |
0 |
| RD |
Same as 1st Packet's RD |
| RA |
0 |
| Z |
0 |
| RCODE |
4 |
| QDCOUNT |
1 |
| ANCOUNT |
0 |
| NSCOUNT |
1 |
| ARCOUNT |
1 |
| DNS Question section |
QNAME |
A.example.com |
| QTYPE |
A (0x0001) |
| QCLASS |
IN (0x0001) |
| DNS Authority section |
NAME |
example.com (Pointer 0xC00E) |
| TYPE |
NS (0x0002) |
| CLASS |
IN (0x0001) |
| TTL |
1 day (86400) |
| RDLENGTH |
6 |
| NSDNAME |
NS1.example.com (NS1 + Pointer 0xC00E) |
| DNS Additional section |
NAME |
NS1.example.com (Pointer 0xC02B) |
| TYPE |
A (0x0001) |
| CLASS |
IN (0x0001) |
| TTL |
1 day (86400) |
| RDLENGTH |
4 |
| ADDRESS |
192.168.1.20 |
3rd Packet.
|
1. Standard query from DNS Client1 (NUT) to DNS Server1 (TN)
|
| IP Header |
Source Address |
NUT_NETZ |
| Destination Address |
SV_NETY |
| UDP Header |
Src Port |
any |
| Dst Port |
53 |
| DNS Header |
ID |
any |
| QR |
0 |
| OPCODE |
0 |
| AA |
any |
| TC |
0 |
| RD |
any |
| RA |
any |
| Z |
any |
| RCODE |
any |
| QDCOUNT |
1 |
| ANCOUNT |
0 |
| NSCOUNT |
0 |
| ARCOUNT |
any |
| DNS Question section |
QNAME |
A.example.com |
| QTYPE |
A (0x0001) |
| QCLASS |
IN (0x0001) |
NUT_NETZ : DNS Client1(NUT)'s address
SV_NETY : DNS Server1(TN)'s address
1. Received standard query QNAME=A.example.com with OPT RR from NUT to Server1(TN).
3. Received standard query QNAME=A.example.com without OPT RR from NUT to Server1(TN)
If NUT has cache function, clear the cache.
RFC2671 Extension Mechanisms for DNS (EDNS0)
4 - OPT pseudo-RR