Re: [netconf] ietf crypto types - permanently hidden

"Rob Wilton (rwilton)" <> Tue, 07 May 2019 11:36 UTC

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From: "Rob Wilton (rwilton)" <>
To: Kent Watsen <>, "" <>
Thread-Topic: [netconf] ietf crypto types - permanently hidden
Date: Tue, 07 May 2019 11:36:36 +0000
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Subject: Re: [netconf] ietf crypto types - permanently hidden
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Hi Kent,

The problem that I have with <generate-key> generating configuration directly in <running> is that <running> on the device is now different from what the management system thinks should be in <running> on the device.

I.e. it breaks the architectural simplicity that it is only the client that controls what goes into in <running>, e.g. perhaps that can be summarized by this flow:

"Update client's desired    ->   "Push to
config"                         <running>"
          ^                        |
          |                        \/
"Client notified of         <-   "Apply config,
changes in <operational>"       <operational> updated"

However, I would not be opposed to allowing <generate-key> create configuration that is persisted separately from <running> and injected into <intended> (e.g. merged with <running>), hence allowing leaf-refs in config validation to work as expected.  I think that this would allow device reboot to work as expected.

If the clients would like to see the keys in the configuration then they can monitor <operational> (or <intended>), and then add the keys, either in raw form, or encrypted in some way.  But I still think that it is architecturally cleaner if it is always the client that updates the <running> configuration and never the device.


From: netconf <> On Behalf Of Kent Watsen
Sent: 03 May 2019 17:24
Subject: Re: [netconf] ietf crypto types - permanently hidden

I had an idea last night that might inch us closer to a solution.

Essentially, the generate/install-key operations always populate <operational>, even for keys that are not-hidden, but then a follow-up operation (something like <copy-config>) replicates the not-hidden key in <operational> to <running>.    Two options:

1) A regular-access admin executes the actions to generate the key, get a CSR, configure a resulting signed certificate, etc. and then, as a second step later in time, a special-access admin replicates the key to <running> (perhaps using standard <get-confg> and <edit-config>), so that it can be included in a standard backup and restored to *any* device (since this key is "not-hidden", it isn't encrypted with a device-specific key and hence can be migrated).

2) A regular-access admin executes the actions to generate the key, get a CSR, configure a resulting signed certificate, etc. and then, as a second step (ideally immediately after), the regular-access admin executes a command like <copy-config>, but rather than copying the entire datastore, it just copies a subtree.

Neither option seems great.  #1 is unappealing being it necessitates coordination between clients.  #2 is unappealing because defining a generic operation for this special case seems too much.

IMO, allowing <generate-key> to create the configuration directly is the only client-friendly answer.

Kent // contributor