[Pdns-dev] Possible ANY, CNAME & cache bug in pdns_recursor ?

[Leen Besselink]

Hi folks,

Possible I've found a bug in pdns_recursor, it will return a different
answer after I've requested more information.

I've tested it with the Debian package (on Debian stable ofcourse).

$  dpkg -s pdns-recursor | egrep '^(Maintainer|Version):'
Maintainer: bert hubert <bert.hubert at netherlabs.nl>
Version: 3.1.3-1

Below is an account of the behaviour. I've also noticed dnscache just
returns the CNAME when requesting ANY, which is probably not a bad idea.

$ dig @127.0.0.1 -p 1234 www.ipv6.org A

; <<>> DiG 9.2.4 <<>> @127.0.0.1 -p 1234 www.ipv6.org A
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51965
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.ipv6.org.                  IN      A

;; ANSWER SECTION:
www.ipv6.org.           3600    IN      CNAME   shake.stacken.kth.se.
shake.stacken.kth.se.   3600    IN      A       130.237.234.40

;; Query time: 527 msec
;; SERVER: 127.0.0.1#1234(127.0.0.1)
;; WHEN: Fri Sep 22 11:29:59 2006
;; MSG SIZE  rcvd: 80

$ dig @127.0.0.1 -p 1234 www.ipv6.org ANY

; <<>> DiG 9.2.4 <<>> @127.0.0.1 -p 1234 www.ipv6.org ANY
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33401
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.ipv6.org.                  IN      ANY

;; ANSWER SECTION:
www.ipv6.org.           3596    IN      CNAME   shake.stacken.kth.se.
shake.stacken.kth.se.   3596    IN      A       130.237.234.40

;; Query time: 6 msec
;; SERVER: 127.0.0.1#1234(127.0.0.1)
;; WHEN: Fri Sep 22 11:30:03 2006
;; MSG SIZE  rcvd: 80

$ dig @127.0.0.1 -p 1234 www.ipv6.org AAAA

; <<>> DiG 9.2.4 <<>> @127.0.0.1 -p 1234 www.ipv6.org AAAA
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27139
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.ipv6.org.                  IN      AAAA

;; ANSWER SECTION:
www.ipv6.org.           3594    IN      CNAME   shake.stacken.kth.se.
shake.stacken.kth.se.   3600    IN      AAAA    2001:6b0:1:ea:202:a5ff:fecd:13a6

;; Query time: 515 msec
;; SERVER: 127.0.0.1#1234(127.0.0.1)
;; WHEN: Fri Sep 22 11:30:06 2006
;; MSG SIZE  rcvd: 92

$ dig @127.0.0.1 -p 1234 www.ipv6.org ANY 

; <<>> DiG 9.2.4 <<>> @127.0.0.1 -p 1234 www.ipv6.org ANY
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11425
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.ipv6.org.                  IN      ANY

;; ANSWER SECTION:
www.ipv6.org.           3589    IN      CNAME   shake.stacken.kth.se.
shake.stacken.kth.se.   3596    IN      AAAA    2001:6b0:1:ea:202:a5ff:fecd:13a6
shake.stacken.kth.se.   3589    IN      A       130.237.234.40

;; Query time: 7 msec
;; SERVER: 127.0.0.1#1234(127.0.0.1)
;; WHEN: Fri Sep 22 11:30:10 2006
;; MSG SIZE  rcvd: 108

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