Questions about automatic KSK and using an additional stand-by KSK

[Bernd Naumann]

Hi Matthijs, thanks for your response.


On 24.02.25 9:47 AM, Matthijs Mekking wrote:
> Hi Bernd,
> 
> Non-signing keys (for example a stand-by key), is a bit tricky in
> dnssec-policy and not fully supported.
> 

Yeah I figured that in the mean time :/

But what I don't understand; RFC 7583 explicit mentioned pre-publish of
DSDATA of ZSK, but not for KSK (IIUC)?

(Or is the 'market-share' of standby keys that low and most people using
a single KSK/ZSK and doing automatic roll over? How high is the chance
anyway to need an emergency key revocation and key rotation?)

Now, I wanted to test an KSK roll over with the following procedure.

* gen KSK-1; gen ZSK-1; gen KSK-2 (offline)
* Add KSK-1, KSK-2, ZSK-1 to the zone
* Sign DNSKEY with KSK-1; sign zone with ZSK-1
* Publish 2x DS for DNSKEY 257
* activate KSK-2; revoke KSK-1; sign DNSKEY with KSK-2 and sign zone
with ZSK-1


> In 9.18, I would suggest to disable inline-signing and just add the
> DNSKEY record to the zone. Don't put the key files for the stand-by key
> in the 'key-directory', this should only hold signing keys.
> 

Jep I've done that; except "Don't put the key files for the stand-by key
> in the 'key-directory'". You the `.private` and `.state` file? (I
added either the `.key` and on a second run `.key` and `.state`.)


> In 9.20 this is fixed and you should be able to add the DNSKEY record to
> the zone, even with inline-signing enabled.
> 

K, lets see if I got 9.20 for OpenWrt. (Or I need to test on Debian)

> Also note that dnssec-policy does not support RFC 5011 (yet).
> 

I'm not sure I understand what you say? How does dnssec-policy interact
with 5011? (Or are you talking about, that a new auto generated key got
auto added to trust-anchros?)

I've added my KSK to the trust-anchor as initial-key and `rdnc
manged-keys` picked that up... (Btw: Can I change to
30-day-delay-till-trust-established? Like to 1 days for testing purpose?)


Thanks again,
Bernd


> Best regards,
> 
> Matthijs
> 
> 
> On 21-02-2025 12:32, Bernd Naumann wrote:
>> I've followed the ARM and the DNSSEC Guide, as well as some ISC KB blog
>> posts.
>>
>> What I got working on BIND 9.18.33:
>> * adding a dnsssec-policy
>> * adding a zone using that dnssec-policy
>>     - setting only SOA, NS, and the AAAA for NS for a minimal zone
>> * reload zone
>>
>> I got an KSK and ZSK; the zone got signed; I added the KSK to
>> `trust-anchors` as an `initial-key`, and saw that the key got /managed/.
>>
>> So far so good.
>>
>> ```
>> dnssec-policy "dn42-ec" {
>>      keys {
>>          ksk lifetime P1Y algorithm ecdsa256;
>>          zsk lifetime P60D algorithm ecdsa256;
>>      };
>>      purge-keys 0;
>> };
>>
>> zone "example.dn42" {
>>          type primary;
>>          file "/etc/bind/db.dn42.example";
>>          dnssec-policy dn42-ec;
>>          inline-signing yes;
>>          allow-transfer {
>>                  fd00::/8;
>>          };
>> };
>> ```
>>
>> ```
>> # cat /etc/bind/keys/Kexample.dn42.+013+03829.key
>> ; This is a key-signing key, keyid 3829, for example.dn42.
>> ; Created: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Publish: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Activate: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Inactive: 20260220195943 (Fri Feb 20 19:59:43 2026)
>> ; Delete: 20260221215943 (Sat Feb 21 21:59:43 2026)
>> ; SyncPublish: 20250221210443 (Fri Feb 21 21:04:43 2025)
>> example.dn42. 3600 IN DNSKEY 257 3 13
>> pMlQUzpKNh2rgEh+DsazO8AiOHKFSpIvUltNPufKR26CugUU1p/1E8fi
>> atOqnOKIqUqrW+EJF/+RrgDPxfhW/A==
>>
>> # cat /etc/bind/keys/Kexample.dn42.+013+41655.key
>> ; This is a zone-signing key, keyid 41655, for example.dn42.
>> ; Created: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Publish: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Activate: 20250220195943 (Thu Feb 20 19:59:43 2025)
>> ; Inactive: 20250421195943 (Mon Apr 21 19:59:43 2025)
>> ; Delete: 20250501210443 (Thu May  1 21:04:43 2025)
>> example.dn42. 3600 IN DNSKEY 256 3 13
>> oRwtJvxmISF4H9eMXkbqgL87muMvwP/D3v+dzki0GoYhl3d7OD03Jaeg
>> ykM+Qra0swAGHNfpprwsmjiOL7J00Q==
>> ```
>>
>>
>> I then generated an stand-by key `dnssec-keygen -G` and included it to
>> the zone.
>>
>> I tried sync, freeze, /update/, reload, thaw; and
>> I tried to `update add` the DNSKEY Record.
>>
>>
>> But, my issue is now: **I don't see the second KSK in the zone.**
>>
>> I went through the manual generation and sign process and IIRC adding a
>> second KSK and seeing afterwards 2x KSK and 1x ZKS wasn't an issue.
>>
>> What mistakes I do when trying to add a stand-by KSK to a auto-managed
>> zone? Or do I need to stick with the manual update and signing process?
>>
>> (In the end I want to have the second KSK known to resolver so they can
>> manage (rfc 5011) that key for later revocation and roll-over events.)
>>
>> Thanks.
>> Bernd
>>
>>

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