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Elixir Cross Referencer

; Check if fallback to the parent side works when MAX_TARGET_NX is reached.

server:
	module-config: "iterator"
	trust-anchor-signaling: no
	target-fetch-policy: "0 0 0 0 0"
	verbosity: 3
	access-control: 127.0.0.1 allow_snoop
	qname-minimisation: no
	minimal-responses: no
	rrset-roundrobin: no

stub-zone:
	name: "."
	stub-addr: 193.0.14.129 	# K.ROOT-SERVERS.NET.
CONFIG_END

SCENARIO_BEGIN Test the NXNS fallback

; K.ROOT-SERVERS.NET.
RANGE_BEGIN 0 100
	ADDRESS 193.0.14.129
	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			. IN NS
		SECTION ANSWER
			. IN NS	K.ROOT-SERVERS.NET.
		SECTION ADDITIONAL
			K.ROOT-SERVERS.NET.	IN	A	193.0.14.129
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype subdomain
		ADJUST copy_id copy_query
		REPLY QR NOERROR
		SECTION QUESTION
			example.com. IN A
		SECTION AUTHORITY
			com.	IN NS	a.gtld-servers.net.
		SECTION ADDITIONAL
			a.gtld-servers.net.	IN 	A	192.5.6.30
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode subdomain
		ADJUST copy_id copy_query
		REPLY QR NOERROR
		SECTION QUESTION
			nonexistant.com. IN A
		SECTION AUTHORITY
			com.	IN NS	a.gtld-servers.net.
		SECTION ADDITIONAL
			a.gtld-servers.net.	IN 	A	192.5.6.30
	ENTRY_END
RANGE_END

; a.gtld-servers.net.
RANGE_BEGIN 0 100
	ADDRESS 192.5.6.30
	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			com. IN NS
		SECTION ANSWER
			com.    IN NS   a.gtld-servers.net.
		SECTION ADDITIONAL
			a.gtld-servers.net.     IN      A       192.5.6.30
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype subdomain
		ADJUST copy_id copy_query
		REPLY QR NOERROR
		SECTION QUESTION
			example.com. IN A
		SECTION AUTHORITY
			example.com.	IN NS	ns.example.com.
		SECTION ADDITIONAL
			ns.example.com.	10 IN A		1.2.3.4
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode subdomain
		ADJUST copy_id copy_query
		REPLY QR NOERROR
		SECTION QUESTION
			nonexistant.com. IN A
		SECTION AUTHORITY
			nonexistant.com. IN NS	ns.example.com.
		SECTION ADDITIONAL
			ns.example.com.	 10 IN A	1.2.3.4
	ENTRY_END
RANGE_END

; ns.example.com.
RANGE_BEGIN 0 100
	ADDRESS 1.2.3.4
	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			example.com. IN NS
		SECTION ANSWER
			example.com.    IN NS   ns1.nonexistant.com.
			example.com.    IN NS   ns2.nonexistant.com.
			example.com.    IN NS   ns3.nonexistant.com.
			example.com.    IN NS   ns4.nonexistant.com.
			example.com.    IN NS   ns5.nonexistant.com.
			example.com.    IN NS   ns6.nonexistant.com.
			example.com.    IN NS   ns7.nonexistant.com.
			example.com.    IN NS   ns8.nonexistant.com.
			example.com.    IN NS   ns9.nonexistant.com.
			example.com.    IN NS   ns10.nonexistant.com.
			example.com.    IN NS   ns11.nonexistant.com.
			example.com.    IN NS   ns12.nonexistant.com.
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			ns.example.com. IN A
		SECTION ANSWER
			ns.example.com. 10 IN A 1.2.3.4
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			ns.example.com. IN AAAA
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode subdomain
		ADJUST copy_id copy_query
		REPLY QR NXDOMAIN
		SECTION QUESTION
			nonexistant.com. IN A
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			a.example.com. IN A
		SECTION ANSWER
			a.example.com. IN A	10.20.30.40
		SECTION AUTHORITY
			example.com.    IN NS   ns1.nonexistant.com.
			example.com.    IN NS   ns2.nonexistant.com.
			example.com.    IN NS   ns3.nonexistant.com.
			example.com.    IN NS   ns4.nonexistant.com.
			example.com.    IN NS   ns5.nonexistant.com.
			example.com.    IN NS   ns6.nonexistant.com.
			example.com.    IN NS   ns7.nonexistant.com.
			example.com.    IN NS   ns8.nonexistant.com.
			example.com.    IN NS   ns9.nonexistant.com.
			example.com.    IN NS   ns10.nonexistant.com.
			example.com.    IN NS   ns11.nonexistant.com.
			example.com.    IN NS   ns12.nonexistant.com.
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			b.example.com. IN A
		SECTION ANSWER
			b.example.com. IN A	10.20.30.40
		SECTION AUTHORITY
			example.com.    IN NS   ns1.nonexistant.com.
			example.com.    IN NS   ns2.nonexistant.com.
			example.com.    IN NS   ns3.nonexistant.com.
			example.com.    IN NS   ns4.nonexistant.com.
			example.com.    IN NS   ns5.nonexistant.com.
			example.com.    IN NS   ns6.nonexistant.com.
			example.com.    IN NS   ns7.nonexistant.com.
			example.com.    IN NS   ns8.nonexistant.com.
			example.com.    IN NS   ns9.nonexistant.com.
			example.com.    IN NS   ns10.nonexistant.com.
			example.com.    IN NS   ns11.nonexistant.com.
			example.com.    IN NS   ns12.nonexistant.com.
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			c.example.com. IN A
		SECTION ANSWER
			c.example.com. IN A	10.20.30.40
		SECTION AUTHORITY
			example.com.    IN NS   ns1.nonexistant.com.
			example.com.    IN NS   ns2.nonexistant.com.
			example.com.    IN NS   ns3.nonexistant.com.
			example.com.    IN NS   ns4.nonexistant.com.
			example.com.    IN NS   ns5.nonexistant.com.
			example.com.    IN NS   ns6.nonexistant.com.
			example.com.    IN NS   ns7.nonexistant.com.
			example.com.    IN NS   ns8.nonexistant.com.
			example.com.    IN NS   ns9.nonexistant.com.
			example.com.    IN NS   ns10.nonexistant.com.
			example.com.    IN NS   ns11.nonexistant.com.
			example.com.    IN NS   ns12.nonexistant.com.
	ENTRY_END

	ENTRY_BEGIN
		MATCH opcode qtype qname
		ADJUST copy_id
		REPLY QR NOERROR
		SECTION QUESTION
			d.example.com. IN A
		SECTION ANSWER
			d.example.com. IN A	10.20.30.40
		SECTION AUTHORITY
			example.com.    IN NS   ns1.nonexistant.com.
			example.com.    IN NS   ns2.nonexistant.com.
			example.com.    IN NS   ns3.nonexistant.com.
			example.com.    IN NS   ns4.nonexistant.com.
			example.com.    IN NS   ns5.nonexistant.com.
			example.com.    IN NS   ns6.nonexistant.com.
			example.com.    IN NS   ns7.nonexistant.com.
			example.com.    IN NS   ns8.nonexistant.com.
			example.com.    IN NS   ns9.nonexistant.com.
			example.com.    IN NS   ns10.nonexistant.com.
			example.com.    IN NS   ns11.nonexistant.com.
			example.com.    IN NS   ns12.nonexistant.com.
	ENTRY_END
RANGE_END

STEP 1 QUERY
ENTRY_BEGIN
REPLY RD
SECTION QUESTION
a.example.com. IN A
ENTRY_END

; This was resolved by asking the parent side nameservers
STEP 2 CHECK_ANSWER
ENTRY_BEGIN
MATCH all
REPLY QR RD RA NOERROR
SECTION QUESTION
a.example.com.	IN A
SECTION ANSWER
a.example.com.	IN A	10.20.30.40
SECTION AUTHORITY
example.com.    IN NS   ns1.nonexistant.com.
example.com.    IN NS   ns2.nonexistant.com.
example.com.    IN NS   ns3.nonexistant.com.
example.com.    IN NS   ns4.nonexistant.com.
example.com.    IN NS   ns5.nonexistant.com.
example.com.    IN NS   ns6.nonexistant.com.
example.com.    IN NS   ns7.nonexistant.com.
example.com.    IN NS   ns8.nonexistant.com.
example.com.    IN NS   ns9.nonexistant.com.
example.com.    IN NS   ns10.nonexistant.com.
example.com.    IN NS   ns11.nonexistant.com.
example.com.    IN NS   ns12.nonexistant.com.
ENTRY_END

; The child side nameservers are now known to Unbound

; Query again, the child server nameservers will be asked now
STEP 3 QUERY
ENTRY_BEGIN
REPLY RD
SECTION QUESTION
b.example.com. IN A
ENTRY_END

; This was resolved by falling back to the parent side nameservers
STEP 4 CHECK_ANSWER
ENTRY_BEGIN
MATCH all
REPLY QR RD RA NOERROR
SECTION QUESTION
b.example.com.	IN A
SECTION ANSWER
b.example.com.	IN A	10.20.30.40
SECTION AUTHORITY
example.com.    IN NS   ns1.nonexistant.com.
example.com.    IN NS   ns2.nonexistant.com.
example.com.    IN NS   ns3.nonexistant.com.
example.com.    IN NS   ns4.nonexistant.com.
example.com.    IN NS   ns5.nonexistant.com.
example.com.    IN NS   ns6.nonexistant.com.
example.com.    IN NS   ns7.nonexistant.com.
example.com.    IN NS   ns8.nonexistant.com.
example.com.    IN NS   ns9.nonexistant.com.
example.com.    IN NS   ns10.nonexistant.com.
example.com.    IN NS   ns11.nonexistant.com.
example.com.    IN NS   ns12.nonexistant.com.
ENTRY_END

; Query a third time, this will get the cached NXDOMAINs (no NX counter for
; those) and will go to the parent as a last resort. This query will test that
; we will not have resolution for the lame(parent side) addresses that could
; raise the NX counter because of no address addition to the delegation point
; (the same addresses are already there).
STEP 5 QUERY
ENTRY_BEGIN
REPLY RD
SECTION QUESTION
c.example.com. IN A
ENTRY_END

; This was resolved by going back to the parent side nameservers (child side
; was exhausted from cache and queries < MAX_TARGET_NX).
STEP 6 CHECK_ANSWER
ENTRY_BEGIN
MATCH all
REPLY QR RD RA NOERROR
SECTION QUESTION
c.example.com.	IN A
SECTION ANSWER
c.example.com.	IN A	10.20.30.40
SECTION AUTHORITY
example.com.    IN NS   ns1.nonexistant.com.
example.com.    IN NS   ns2.nonexistant.com.
example.com.    IN NS   ns3.nonexistant.com.
example.com.    IN NS   ns4.nonexistant.com.
example.com.    IN NS   ns5.nonexistant.com.
example.com.    IN NS   ns6.nonexistant.com.
example.com.    IN NS   ns7.nonexistant.com.
example.com.    IN NS   ns8.nonexistant.com.
example.com.    IN NS   ns9.nonexistant.com.
example.com.    IN NS   ns10.nonexistant.com.
example.com.    IN NS   ns11.nonexistant.com.
example.com.    IN NS   ns12.nonexistant.com.
ENTRY_END

; Allow for the nameserver glue to expire
STEP 10 TIME_PASSES ELAPSE 11

; Query again for the parent side fallback
STEP 11 QUERY
ENTRY_BEGIN
REPLY RD
SECTION QUESTION
d.example.com. IN A
ENTRY_END

; This was resolved by falling back to the parent side nameservers
STEP 12 CHECK_ANSWER
ENTRY_BEGIN
MATCH all
REPLY QR RD RA NOERROR
SECTION QUESTION
d.example.com.	IN A
SECTION ANSWER
d.example.com.	IN A	10.20.30.40
SECTION AUTHORITY
example.com.    IN NS   ns1.nonexistant.com.
example.com.    IN NS   ns2.nonexistant.com.
example.com.    IN NS   ns3.nonexistant.com.
example.com.    IN NS   ns4.nonexistant.com.
example.com.    IN NS   ns5.nonexistant.com.
example.com.    IN NS   ns6.nonexistant.com.
example.com.    IN NS   ns7.nonexistant.com.
example.com.    IN NS   ns8.nonexistant.com.
example.com.    IN NS   ns9.nonexistant.com.
example.com.    IN NS   ns10.nonexistant.com.
example.com.    IN NS   ns11.nonexistant.com.
example.com.    IN NS   ns12.nonexistant.com.
ENTRY_END

SCENARIO_END