Re: [PATCH proxmox/yew-pwt/datacenter-manager/installer v3 00/38] add auto-installer integration

[Dominik Csapak <d.csapak@proxmox.com>]

On 4/17/26 1:26 PM, Lukas Wagner wrote:
> On Fri Apr 17, 2026 at 11:48 AM CEST, Dominik Csapak wrote:
>>
>>
>> On 4/17/26 11:23 AM, Lukas Wagner wrote:
>>> On Fri Apr 17, 2026 at 11:10 AM CEST, Dominik Csapak wrote:
>>>> also two things i forgot:
>>>>
>>>> i think we could make the endpoint available without authentication?
>>>> at least that's what i would have expected, since the current
>>>> http endpoints also had to be public?
>>>>
>>>> second things is about the tokens + acl, I'd probably
>>>> use the existing token acl mechanism, so instead of
>>>> having custom tokens + a token list per answer,
>>>>
>>>> use the standard pdm tokens + an acl path (e.g.
>>>> /system/auto-installation/answers/<id> ) maybe a separate privilege
>>>> could make sense here, so the token does not have access
>>>> to anything else?
>>>>
>>>
>>> Check out my response to v2, which is (I think) the main reason why it
>>> is implemented like it is right now:
>>>
>>> https://lore.proxmox.com/all/DETMUXY1Q877.32G593TWC52WW@proxmox.com/T/#u
>>>
>>
>> ok i see, but i have some counter arguments to that, for brevity, here
>> is part of your response from that mail:
>>
>> ---
>> I think this is dangerous.
>>
>> While the answer-file does not leak any passwords (seems like the root
>> password is hashed), it still contains semi-sensitive data (email address,
>> SSH key, FQDN, etc.). Also, since each POST creates a new entry in the
>> installations JSON file, an unauthenticated user could abuse this to
>> make the PDM system run out of disk space (or simply disturb operations
>> by creating bogus entries).
>> ---
>>
>>
>> We already had the requirement for a http endpoint to be unauthenticated
>> so for a secured and protected network, this should be a non issue
> 
> Yes, but I think it's a big difference if we integrate something like
> this into PDM natively. There will always be users who, against our
> recommendations, expose the PDM web interface directly to the internet
> or other untrusted network environments. I would very much argue
> against returning any kind of (semi)-sensitive information from the API
> without proper access controls, even if it is opt-in.

why is it different? previously we *needed* the admin to expose
it unauthenticated if he wanted to use, it, i proposed
making authentication optional, it's still a win from a security pov?

IMO this boils down what we choose, neither options is more correct here.

do we trust the admin to properly configure his environment?
if yes, then we can leave it up to their choice if they want to protect
these endpoints with a token

(for example, we allow the migration traffic to be unencrypted too,
but only if the admin decides that)

we could print a big warning that this info is publicly exposed if
no token restriction is used, or something like this.

but as i said this is more of choice, not a purely technical argument
> 
>>
>> also i'm not for making it unauthenticated for all responses, but
>> make it the admins choice.
>>
>> as for the DOS vector of pdm, we could check if the user was
>> authenticated, and only generate the data then.
> 
> There is no user information available when the installer requests the
> answer file, how would we check it?
> 
> Sorry, maybe I'm misunderstanding your proposal here :)
> 

how it currently works is that the iso must be prepared with a token,
i'd propose leaving that in, but only as an option if the admin
wants to do the authentication, but not as a requirement

the api could check if there is a user in the rpcenv anyway and check
their permissions against the available prepared answers

>>
>> but how much data is that really? e.g. each api call (authenticated or
>> not) creates a new line in the access log. so with enough api calls,
>> i can fill up the disk too...
> 
> You're right about the access log. That being said, an unauthenticated
> user would still be able to create bogus entries installation entries
> that would show up in the UI.
> 

btw. most of the pain with the authentication imho here comes
from having separate api tokens just for the automated installs
and the lack of guidance what the user should do.

if we e.g. can autogenerate the 'proxmox-auto-install-assistant'
cli command with the gui and make it copyable, makes this probably
a lot less cumbersome