DNS/毒盛/キャッシュ上書き/NS変更毒/デモ2について、ここに記述してください。

<<TableOfContents()>>

BINDリゾルバーでは、キャッシュにあるAA flag Answer SectionのNSが上書きされてしまうデモです。

(結論) BINDは毒盛しやすい。

== 前提確認 ==
キャッシュにあることを確認する。
{{{
$ dig f.flip.e-ontap.com @127.0.0.1

; <<>> DiG 9.12.3 <<>> f.flip.e-ontap.com @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6441
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
; COOKIE: 5533a5c44408662f7b97a1305c22d84177351090fff02b6e (good)
;; QUESTION SECTION:
;f.flip.e-ontap.com.		IN	A

;; ANSWER SECTION:
f.flip.e-ontap.com.	60	IN	A	150.42.6.1

;; Query time: 11 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: 水 12月 26 10:24:17 JST 2018
;; MSG SIZE  rcvd: 91
}}}

{{{
tmaeno@u16:~$ dig +norec -t ns flip.e-ontap.com @127.0.0.1

; <<>> DiG 9.12.3 <<>> +norec -t ns flip.e-ontap.com @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24262
;; flags: qr ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 2

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
; COOKIE: f806034e71c02a2d331a9ae25c22d84fb57fbf4f5355ab81 (good)
;; QUESTION SECTION:
;flip.e-ontap.com.		IN	NS

;; ANSWER SECTION:
flip.e-ontap.com.	3346	IN	NS	ns.flip.e-ontap.com.

;; ADDITIONAL SECTION:
ns.flip.e-ontap.com.	370	IN	A	150.42.6.1

;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: 水 12月 26 10:24:31 JST 2018
;; MSG SIZE  rcvd: 106
}}}

== テスト ==
時刻に注意: ;; WHEN: 水 12月 26 10:25:36 JST 2018
 
{{{
tmaeno@u16:~$ dig g.flip.e-ontap.com @127.0.0.1

; <<>> DiG 9.12.3 <<>> g.flip.e-ontap.com @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45604
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
; COOKIE: 8ffee66abfd69ae1ef887ca45c22d8906c5a0c23f630af7b (good)
;; QUESTION SECTION:
;g.flip.e-ontap.com.		IN	A

;; ANSWER SECTION:
g.flip.e-ontap.com.	60	IN	A	150.42.6.1

;; Query time: 11 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: 水 12月 26 10:25:36 JST 2018
;; MSG SIZE  rcvd: 91
}}}

== どうかな ==
{{{

tmaeno@u16:~$ dig +norec -t ns flip.e-ontap.com @127.0.0.1

; <<>> DiG 9.12.3 <<>> +norec -t ns flip.e-ontap.com @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 9682
;; flags: qr ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 2

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
; COOKIE: ad9b1a93d89f0a9ba54faf195c22d89571e1ad973a9fe0cc (good)
;; QUESTION SECTION:
;flip.e-ontap.com.		IN	NS

;; ANSWER SECTION:
flip.e-ontap.com.	3276	IN	NS	ns.flip.internot.jp.

;; ADDITIONAL SECTION:
ns.flip.internot.jp.	81695	IN	A	150.42.6.5

;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: 水 12月 26 10:25:41 JST 2018
;; MSG SIZE  rcvd: 122
}}}

毒がはいっています。

{{{
$ dig h.flip.e-ontap.com @127.0.0.1

; <<>> DiG 9.12.3 <<>> h.flip.e-ontap.com @127.0.0.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51456
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1220
; COOKIE: c71e4949401ae028e211980b5c22d992026eb42db0af0fa1 (good)
;; QUESTION SECTION:
;h.flip.e-ontap.com.		IN	A

;; ANSWER SECTION:
h.flip.e-ontap.com.	60	IN	A	150.42.6.5

;; Query time: 12 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: 水 12月 26 10:29:54 JST 2018
;; MSG SIZE  rcvd: 91

}}}