- Fix that DS queries with referral replies are answered straight

  away, without a repeat query picking the DS from cache.
  The correct reply should have been an answer, the reply is fixed
  by the scrubber to have the answer in the answer section.

git-svn-id: file:///svn/unbound/trunk@4430 be551aaa-1e26-0410-a405-d3ace91eadb9

diff --git a/doc/Changelog b/doc/Changelog
index 0e0a82c4a04db7e41cb32c9143ae49c85b757bc3..9036882eb1d01a2e553f069782f6f213f2333d9c 100644 (file)
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,9 @@
+2 January 2017: Wouter
+       - Fix that DS queries with referral replies are answered straight
+         away, without a repeat query picking the DS from cache.
+         The correct reply should have been an answer, the reply is fixed
+         by the scrubber to have the answer in the answer section.
+
 15 December 2017: Wouter
        - Fix timestamp failure because of clang optimizer failure, by
          disabling -O2 when the compiler --version is clang.

diff --git a/iterator/iter_scrub.c b/iterator/iter_scrub.c
index 1bee85c0b991df219dae0ade95a0ec49dc7e2edd..12580dcdb539578b7cbed562847731ab742bd8fd 100644 (file)
--- a/iterator/iter_scrub.c
+++ b/iterator/iter_scrub.c
@@ -503,6 +503,24 @@ scrub_normalize(sldns_buffer* pkt, struct msg_parse* msg,
                                continue;
                        }
                }
+               /* if this is type DS and we query for type DS we just got
+                * a referral answer for our type DS query, fix packet */
+               if(rrset->type==LDNS_RR_TYPE_DS &&
+                       qinfo->qtype == LDNS_RR_TYPE_DS &&
+                       dname_pkt_compare(pkt, qinfo->qname, rrset->dname) == 0) {
+                       rrset->section = LDNS_SECTION_ANSWER;
+                       msg->ancount = rrset->rr_count + rrset->rrsig_count;
+                       msg->nscount = 0;
+                       msg->arcount = 0;
+                       msg->an_rrsets = 1;
+                       msg->ns_rrsets = 0;
+                       msg->ar_rrsets = 0;
+                       msg->rrset_count = 1;
+                       msg->rrset_first = rrset;
+                       msg->rrset_last = rrset;
+                       rrset->rrset_all_next = NULL;
+                       return 1;
+               }
                mark_additional_rrset(pkt, msg, rrset);
                prev = rrset;
                rrset = rrset->rrset_all_next;

diff --git a/testdata/iter_ds_referral.rpl b/testdata/iter_ds_referral.rpl
new file mode 100644 (file)
index 0000000..e320942
--- /dev/null
+++ b/testdata/iter_ds_referral.rpl
@@ -0,0 +1,213 @@
+; config options
+; The island of trust is at example.com
+server:
+       trust-anchor: "example.com.    3600    IN      DS      2854 3 1 46e4ffc6e9a4793b488954bd3f0cc6af0dfb201b"
+       val-override-date: "20070916134226"
+       target-fetch-policy: "0 0 0 0 0"
+       fake-sha1: yes
+       trust-anchor-signaling: no
+
+stub-zone:
+       name: "."
+       stub-addr: 193.0.14.129         # K.ROOT-SERVERS.NET.
+CONFIG_END
+
+SCENARIO_BEGIN Test iterator with DS query and referral reply
+
+; 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 subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+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 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.                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   ns.example.com.
+example.com.    3600    IN      RRSIG   NS 3 2 3600 20070926134150 20070829134150 2854 example.com. MC0CFQCN+qHdJxoI/2tNKwsb08pra/G7aAIUAWA5sDdJTbrXA1/3OaesGBAO3sI= ;{id = 2854}
+SECTION ADDITIONAL
+ns.example.com.         IN      A       1.2.3.4
+ns.example.com. 3600    IN      RRSIG   A 3 3 3600 20070926135752 20070829135752 2854 example.com. MC0CFQCMSWxVehgOQLoYclB9PIAbNP229AIUeH0vNNGJhjnZiqgIOKvs1EhzqAo= ;{id = 2854}
+ENTRY_END
+
+; response to DNSKEY priming query
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+example.com. IN DNSKEY
+SECTION ANSWER
+example.com.    3600    IN      DNSKEY  256 3 3 ALXLUsWqUrY3JYER3T4TBJII s70j+sDS/UT2QRp61SE7S3E EXopNXoFE73JLRmvpi/UrOO/Vz4Se 6wXv/CYCKjGw06U4WRgR YXcpEhJROyNapmdIKSx hOzfLVE1gqA0PweZR8d tY3aNQSRn3sPpwJr6Mi /PqQKAMMrZ9ckJpf1+b QMOOvxgzz2U1GS18b3y ZKcgTMEaJzd/GZYzi/B N2DzQ0MsrSwYXfsNLFO Bbs8PJMW4LYIxeeOe6rUgkWOF 7CC9Dh/dduQ1QrsJhmZAEFfd6ByYV+ ;{id = 2854 (zsk), size = 1688b}
+example.com. 3600    IN      RRSIG   DNSKEY DSA 2 3600 20070926134150 20070829134150 2854 example.com. MCwCFBQRtlR4BEv9ohi+PGFjp+AHsJuHAhRCvz0shggvnvI88DFnBDCczHUcVA== ;{id = 2854}
+SECTION AUTHORITY
+example.com.   IN NS   ns.example.com.
+example.com.    3600    IN      RRSIG   NS 3 2 3600 20070926134150 20070829134150 2854 example.com. MC0CFQCN+qHdJxoI/2tNKwsb08pra/G7aAIUAWA5sDdJTbrXA1/3OaesGBAO3sI= ;{id = 2854}
+SECTION ADDITIONAL
+ns.example.com.                IN      A       1.2.3.4
+ns.example.com. 3600    IN      RRSIG   A 3 3 3600 20070926135752 20070829135752 2854 example.com. MC0CFQCMSWxVehgOQLoYclB9PIAbNP229AIUeH0vNNGJhjnZiqgIOKvs1EhzqAo= ;{id = 2854}
+ENTRY_END
+
+; note, no specific DS answer here, it replies with the referral for
+; the type DS query
+
+; response for delegation to sub.example.com.
+ENTRY_BEGIN
+MATCH opcode subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN A
+SECTION ANSWER
+SECTION AUTHORITY
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+sub.example.com.        3600    IN      RRSIG   DS 3 3 3600 20070926134150 20070829134150 2854 example.com. MCwCFCW3ix0GD4BSvNLWIbROCJt5DAW9AhRt/kg9kBKJ20UBUdumrBUHqnskdA== ;{id = 2854}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ENTRY_END
+
+RANGE_END
+
+; ns.sub.example.com.
+RANGE_BEGIN 0 100
+       ADDRESS 1.2.3.6
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN NS
+SECTION ANSWER
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      RRSIG   NS 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. wcpHeBILHfo8C9uxMhcW03gcURZeUffiKdSTb50ZjzTHgMNhRyMfpcvSpXEd9548A9UTmWKeLZChfr5Z/glONw== ;{id = 30899}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ns.sub.example.com.     3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. UF7shD/gt1FOp2UHgLTNbPzVykklSXFMEtJ1xD+Hholwf/PIzd7zoaIttIYibNa4fUXCqMg22H9P7MRhfmFe6g== ;{id = 30899}
+ENTRY_END
+
+; response to DNSKEY priming query
+; sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN DNSKEY
+SECTION ANSWER
+sub.example.com.        3600    IN      DNSKEY  256 3 5 AQPQ41chR9DEHt/aIzIFAqanbDlRflJoRs5yz1jFsoRIT7dWf0r+PeDuewdxkszNH6wnU4QL8pfKFRh5PIYVBLK3 ;{id = 30899 (zsk), size = 512b}
+sub.example.com.        3600    IN      RRSIG   DNSKEY 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. uNGp99iznjD7oOX02XnQbDnbg75UwBHRvZSKYUorTKvPUnCWMHKdRsQ+mf+Fx3GZ+Fz9BVjoCmQqpnfgXLEYqw== ;{id = 30899}
+SECTION AUTHORITY
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      RRSIG   NS 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. wcpHeBILHfo8C9uxMhcW03gcURZeUffiKdSTb50ZjzTHgMNhRyMfpcvSpXEd9548A9UTmWKeLZChfr5Z/glONw== ;{id = 30899}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ns.sub.example.com.     3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. UF7shD/gt1FOp2UHgLTNbPzVykklSXFMEtJ1xD+Hholwf/PIzd7zoaIttIYibNa4fUXCqMg22H9P7MRhfmFe6g== ;{id = 30899}
+ENTRY_END
+
+; response to A query
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+www.sub.example.com. IN A
+SECTION ANSWER
+www.sub.example.com. IN A      11.11.11.11
+www.sub.example.com.    3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. 0DqqRfRtm7VSEQ4mmBbzrKRqQAay3JAE8DPDGmjtokrrjN9F1G/HxozDV7bjdIh2EChlQea8FPwf/GepJMUVxg== ;{id = 30899}
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+
+; something for wrong type DS query here
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR REFUSED
+SECTION QUESTION
+sub.example.com. IN DS
+SECTION ANSWER
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+RANGE_END
+
+STEP 1 QUERY
+ENTRY_BEGIN
+REPLY RD DO
+SECTION QUESTION
+sub.example.com. IN DS
+ENTRY_END
+
+; recursion happens here.
+STEP 10 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all
+REPLY QR RD RA AD DO NOERROR
+SECTION QUESTION
+sub.example.com. IN DS
+SECTION ANSWER
+sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+sub.example.com.        3600    IN      RRSIG   DS 3 3 3600 20070926134150 20070829134150 2854 example.com. MCwCFCW3ix0GD4BSvNLWIbROCJt5DAW9AhRt/kg9kBKJ20UBUdumrBUHqnskdA== ;{id = 2854}
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+
+SCENARIO_END

diff --git a/testdata/iter_ds_reply.rpl b/testdata/iter_ds_reply.rpl
new file mode 100644 (file)
index 0000000..ea2b69d
--- /dev/null
+++ b/testdata/iter_ds_reply.rpl
@@ -0,0 +1,225 @@
+; config options
+; The island of trust is at example.com
+server:
+       trust-anchor: "example.com.    3600    IN      DS      2854 3 1 46e4ffc6e9a4793b488954bd3f0cc6af0dfb201b"
+       val-override-date: "20070916134226"
+       target-fetch-policy: "0 0 0 0 0"
+       fake-sha1: yes
+       trust-anchor-signaling: no
+
+stub-zone:
+       name: "."
+       stub-addr: 193.0.14.129         # K.ROOT-SERVERS.NET.
+CONFIG_END
+
+SCENARIO_BEGIN Test iterator with DS query and answer reply
+
+; 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 subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+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 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.                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   ns.example.com.
+example.com.    3600    IN      RRSIG   NS 3 2 3600 20070926134150 20070829134150 2854 example.com. MC0CFQCN+qHdJxoI/2tNKwsb08pra/G7aAIUAWA5sDdJTbrXA1/3OaesGBAO3sI= ;{id = 2854}
+SECTION ADDITIONAL
+ns.example.com.         IN      A       1.2.3.4
+ns.example.com. 3600    IN      RRSIG   A 3 3 3600 20070926135752 20070829135752 2854 example.com. MC0CFQCMSWxVehgOQLoYclB9PIAbNP229AIUeH0vNNGJhjnZiqgIOKvs1EhzqAo= ;{id = 2854}
+ENTRY_END
+
+; response to DNSKEY priming query
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+example.com. IN DNSKEY
+SECTION ANSWER
+example.com.    3600    IN      DNSKEY  256 3 3 ALXLUsWqUrY3JYER3T4TBJII s70j+sDS/UT2QRp61SE7S3E EXopNXoFE73JLRmvpi/UrOO/Vz4Se 6wXv/CYCKjGw06U4WRgR YXcpEhJROyNapmdIKSx hOzfLVE1gqA0PweZR8d tY3aNQSRn3sPpwJr6Mi /PqQKAMMrZ9ckJpf1+b QMOOvxgzz2U1GS18b3y ZKcgTMEaJzd/GZYzi/B N2DzQ0MsrSwYXfsNLFO Bbs8PJMW4LYIxeeOe6rUgkWOF 7CC9Dh/dduQ1QrsJhmZAEFfd6ByYV+ ;{id = 2854 (zsk), size = 1688b}
+example.com. 3600    IN      RRSIG   DNSKEY DSA 2 3600 20070926134150 20070829134150 2854 example.com. MCwCFBQRtlR4BEv9ohi+PGFjp+AHsJuHAhRCvz0shggvnvI88DFnBDCczHUcVA== ;{id = 2854}
+SECTION AUTHORITY
+example.com.   IN NS   ns.example.com.
+example.com.    3600    IN      RRSIG   NS 3 2 3600 20070926134150 20070829134150 2854 example.com. MC0CFQCN+qHdJxoI/2tNKwsb08pra/G7aAIUAWA5sDdJTbrXA1/3OaesGBAO3sI= ;{id = 2854}
+SECTION ADDITIONAL
+ns.example.com.                IN      A       1.2.3.4
+ns.example.com. 3600    IN      RRSIG   A 3 3 3600 20070926135752 20070829135752 2854 example.com. MC0CFQCMSWxVehgOQLoYclB9PIAbNP229AIUeH0vNNGJhjnZiqgIOKvs1EhzqAo= ;{id = 2854}
+ENTRY_END
+
+; DS gets an answer from the authoritative server
+; (like NSD 4.1.0 answers it)
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR AA NOERROR
+SECTION QUESTION
+sub.example.com. IN DS
+SECTION ANSWER
+sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+sub.example.com.        3600    IN      RRSIG   DS 3 3 3600 20070926134150 20070829134150 2854 example.com. MCwCFCW3ix0GD4BSvNLWIbROCJt5DAW9AhRt/kg9kBKJ20UBUdumrBUHqnskdA== ;{id = 2854}
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+
+; response for delegation to sub.example.com.
+ENTRY_BEGIN
+MATCH opcode subdomain
+ADJUST copy_id copy_query
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN A
+SECTION ANSWER
+SECTION AUTHORITY
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+sub.example.com.        3600    IN      RRSIG   DS 3 3 3600 20070926134150 20070829134150 2854 example.com. MCwCFCW3ix0GD4BSvNLWIbROCJt5DAW9AhRt/kg9kBKJ20UBUdumrBUHqnskdA== ;{id = 2854}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ENTRY_END
+
+RANGE_END
+
+; ns.sub.example.com.
+RANGE_BEGIN 0 100
+       ADDRESS 1.2.3.6
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN NS
+SECTION ANSWER
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      RRSIG   NS 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. wcpHeBILHfo8C9uxMhcW03gcURZeUffiKdSTb50ZjzTHgMNhRyMfpcvSpXEd9548A9UTmWKeLZChfr5Z/glONw== ;{id = 30899}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ns.sub.example.com.     3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. UF7shD/gt1FOp2UHgLTNbPzVykklSXFMEtJ1xD+Hholwf/PIzd7zoaIttIYibNa4fUXCqMg22H9P7MRhfmFe6g== ;{id = 30899}
+ENTRY_END
+
+; response to DNSKEY priming query
+; sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+sub.example.com. IN DNSKEY
+SECTION ANSWER
+sub.example.com.        3600    IN      DNSKEY  256 3 5 AQPQ41chR9DEHt/aIzIFAqanbDlRflJoRs5yz1jFsoRIT7dWf0r+PeDuewdxkszNH6wnU4QL8pfKFRh5PIYVBLK3 ;{id = 30899 (zsk), size = 512b}
+sub.example.com.        3600    IN      RRSIG   DNSKEY 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. uNGp99iznjD7oOX02XnQbDnbg75UwBHRvZSKYUorTKvPUnCWMHKdRsQ+mf+Fx3GZ+Fz9BVjoCmQqpnfgXLEYqw== ;{id = 30899}
+SECTION AUTHORITY
+sub.example.com. IN    NS ns.sub.example.com.
+sub.example.com.        3600    IN      RRSIG   NS 5 3 3600 20070926134150 20070829134150 30899 sub.example.com. wcpHeBILHfo8C9uxMhcW03gcURZeUffiKdSTb50ZjzTHgMNhRyMfpcvSpXEd9548A9UTmWKeLZChfr5Z/glONw== ;{id = 30899}
+SECTION ADDITIONAL
+ns.sub.example.com. IN A 1.2.3.6
+ns.sub.example.com.     3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. UF7shD/gt1FOp2UHgLTNbPzVykklSXFMEtJ1xD+Hholwf/PIzd7zoaIttIYibNa4fUXCqMg22H9P7MRhfmFe6g== ;{id = 30899}
+ENTRY_END
+
+; response to A query
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR NOERROR
+SECTION QUESTION
+www.sub.example.com. IN A
+SECTION ANSWER
+www.sub.example.com. IN A      11.11.11.11
+www.sub.example.com.    3600    IN      RRSIG   A 5 4 3600 20070926134150 20070829134150 30899 sub.example.com. 0DqqRfRtm7VSEQ4mmBbzrKRqQAay3JAE8DPDGmjtokrrjN9F1G/HxozDV7bjdIh2EChlQea8FPwf/GepJMUVxg== ;{id = 30899}
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+
+; something for wrong type DS query here
+ENTRY_BEGIN
+MATCH opcode qtype qname
+ADJUST copy_id
+REPLY QR REFUSED
+SECTION QUESTION
+sub.example.com. IN DS
+SECTION ANSWER
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+RANGE_END
+
+STEP 1 QUERY
+ENTRY_BEGIN
+REPLY RD DO
+SECTION QUESTION
+sub.example.com. IN DS
+ENTRY_END
+
+; recursion happens here.
+STEP 10 CHECK_ANSWER
+ENTRY_BEGIN
+MATCH all
+REPLY QR RD RA AD DO NOERROR
+SECTION QUESTION
+sub.example.com. IN DS
+SECTION ANSWER
+sub.example.com.        3600    IN      DS      30899 RSASHA1 1 f7ed618f24d5e5202927e1d27bc2e84a141cb4b3
+sub.example.com.        3600    IN      RRSIG   DS 3 3 3600 20070926134150 20070829134150 2854 example.com. MCwCFCW3ix0GD4BSvNLWIbROCJt5DAW9AhRt/kg9kBKJ20UBUdumrBUHqnskdA== ;{id = 2854}
+SECTION AUTHORITY
+SECTION ADDITIONAL
+ENTRY_END
+
+SCENARIO_END