Thanks for your comments and yes they make sense. I think we mostly have
the same opinion here.
What is achievable with Keycloak today puts a fair bit of the effort on the
application and the RP. Firstly the RP/API would need to be able to find
out how long since the user authenticated, which it can as that can be
added as a claim to the token. The RP can then reject request if it's to
long since the user authenticated. Further, the application (web/UI) would
need to use max_age and/or prompt=login to force the user to
re-authenticate.
Taking this one step further to step-up authentication which we plan to
introduce in the not to distant future. In this case the application can
use acr_values to request step-up. This also needs to most likely be
validated by the RP, which somehow needs to communicate this to the
applications.
Ideally Keycloak would have some support to make this easier and not have
to put all the burden on the app and the RP, but AFAIK there's no real
standard way of doing that. One idea is that we could somehow drive it
through client scopes. Let's say you have a client scope named
"high-risk-scope". Setting a max_age and also an acr value on the client
scope itself within Keycloak means that everytime an application requests a
token with that scope the refresh token timeout would be set accordingly
and the user would be required to authenticate at the appropriate level.
In summary though - this is something that needs to be thought through
properly. Right now I have too many things on my plate to start working on
any sort of design proposal around this, but if anyone from the community
would like to start working on something that would be great.
On Wed, 25 Sep 2019 at 23:17, Martin Maher <gentoo(a)penguindreams.us> wrote:
Stian:
In reading this thread and the OPs concerns, I see three components that
could exert or express control - the Keycloak server; the application
server; and the user.
From reading the OPs concerns, both in the original post and in the later
articulation, it seems as though there is a desire to have the user express
what is a high-risk API . . . "*Therefore end-user wants to
re-authenticate periodically*”, versus your example of the Application
server designating itself as a high-risk for all users.
I agree with your assertion that solving this issue through HTTP
session-timeouts would be problematic, not least of all for SSO type of
authentications.
Having the application server specify to the Keycloak server the
max-length of a valid authorization based upon successful authentication,
would permit the Keycloak server to set the “max-age” attribute, whereby
refresh tokens would no longer be issued or honored after that time,
leading to a requirement to reauthenticate.
The tricky bit for the OPs scenario is creating a method within the
application server for the user to express this to the application, which
could then be conveyed to Keycloak, which could then be set on the user
tokens.
This does lead back to the application server, as you asserted, but I
believe that there would need to be a mechanism, if one does not already
exist, for the application server to communicate this to Keycloak on a
per-user basis. It should also be possible for the Keycloak server to take
a configuration element that permits designation of high-risk and low-risk
APIs, in order to interfere with attempts to downgrade authentication
strengths for sensitive applications.
I hope this makes sense.
Regards,
Martin
On Sep 24, 2019, at 23:55 , Stian Thorgersen <sthorger(a)redhat.com> wrote:
I don't understand what's different with your use-case compared to what I
listed. As I understand it they are both pretty much the same use-case.
In either case different sessions and timeouts are not the correct
solution. Configurable refresh token timeout is probably not a good
solution either, at least not on its own without anything else.
On Wed, 25 Sep 2019 at 03:05, 田畑義之 / TABATA,YOSHIYUKI <
yoshiyuki.tabata.jy(a)hitachi.com> wrote:
So trying to understand your use-case and simplifying things a bit. You
basically have two (or more) different groups of APIs. Let's call these
low-risk APIs and high-risk APIs. When a user invokes the low-risk API they
don't need to authenticate regularly and a session can last for days (or
weeks). For high-risk APIs they need to authenticate more regularly.
This example is a little bit unfitted for our use case.
I give a concrete example.
For example, there are 2 client applications.
Client application A accesses high-risk APIs such as money transfer API.
Client application B accesses low-risk APIs such as balance inquiry API.
In client application A case, it's risky for an end-user to let the client
application to hold a valid refresh token long time because a risk
increases which an attacker sends money using the stolen mobile devices or
which an attacker steals the valid refresh token. Therefore end-user wants
to re-authenticate periodically and the client application guarantees to
end-user that it holds a valid refresh token only limited short time.
In client application B case, it's not risky for an end-user to let the
client application to hold a valid refresh token long time because it is
not much impact for end-user that an attacker checks end user's balance.
Therefore end-user does not want to re-authenticate periodically and the
client application holds a valid refresh token long time prioritizing
usability.
In the above use case, end-user does not trust client applications
completely, so it's meaningless that client application defines the
expiration of a refresh token. And it's meaningful that authorization
server (Keycloak) defines the expiration of a refresh token.
Regards,
Yoshiyuki Tabata
Hitachi, Ltd.
*From:* Stian Thorgersen <sthorger(a)redhat.com>
*Sent:* Tuesday, September 24, 2019 4:45 PM
*To:* TABATA,YOSHIYUKI <yoshiyuki.tabata.jy(a)hitachi.com>
*Cc:* keycloak-dev <keycloak-dev(a)lists.jboss.org>
*Subject:* [!]Re: Re: [keycloak-dev] Override Refresh token lifespan per
client
So trying to understand your use-case and simplifying things a bit. You
basically have two (or more) different groups of APIs. Let's call these
low-risk APIs and high-risk APIs. When a user invokes the low-risk API they
don't need to authenticate regularly and a session can last for days (or
weeks). For high-risk APIs they need to authenticate more regularly.
Now this is solved with looking at when the user last authenticated as
well as how the user was authenticated, not by having different session
timeouts. As we don't have step-up autentication support right now, that
leaves us with requiring users to re-authenticate more regularly for the
high-risk API.
Conceptually I can see at least two different ways to achieve the above:
1) Resource Server is responsible for verifying - the UI uses login=promt
and/or max_age to re-authenticate the user when needed. Further, the
resource server needs to check when user authenticate.
2) Keycloak is responsible for verifying - perhaps Keycloak issues refresh
tokens with shorter duration for specific apps/UIs
Option 2 is problematic as the UI may just as well invoke both low-risk
and high-risk APIs. Further, in the future as we add step-up, high-risk may
be asking for step-up authentication, not re-authentication.
On Tue, 24 Sep 2019 at 07:46, TABATA,YOSHIYUKI <
yoshiyuki.tabata.jy(a)hitachi.com> wrote:
For authorization code flow it makes no sense at all to have different
session timeouts as it is by definition a shared SSO session. Different
security levels should be controlled things like step-up and authentication
timeout, not by having different session timeouts. Further, I'm not sure if
refresh token timeout should be configurable per-client here as end of the
day a new refresh token can easily be obtained as long as the session is
still active.
Clients guarantee to end-users that clients access to end-users' resources
only within the expiration using the tokens. So end-users need to re-login
after the expiration and clients must not refresh tokens after the
expiration.
The expiration depends on each client by security reason, or usability
reason, or so on.
Therefore regardless of which authorization flows we use, we need to make
a difference between session timeouts.
I'm not particularly found of introducing so many settings on a client.
It's difficult to setup and error prone. So this use-case needs to be
described properly and we need to find a decent solution to it. Simply
adding all these settings on a client may work for you, but I doubt others
would understand how and when to use them, and I think it can easily end up
resulting in a lot of error cases.
How about providing a checkbox which enables a one-to-one relationship
between UserSessionModel and ClientSessionModel?
Currently, UserSessionModel and ClientSessionModel are a one-to-many
relationship, and this makes it difficult to set session timeout per
client.
If the checkbox enabled, not link a new ClientSessionModel to the existing
UserSessionModel when a new client which uses the existing authentication
result appeared but make a new UserSessionModel.
If this possible, we don't need to change the way to manage sessions.
Keycloak is a SSO solution and we have no plans on introducing per-client
sessions.
Regards,
Yoshiyuki Tabata
Hitachi, Ltd.
*From:* Stian Thorgersen <sthorger(a)redhat.com>
*Sent:* Friday, September 20, 2019 6:00 PM
*To:* TABATA,YOSHIYUKI <yoshiyuki.tabata.jy(a)hitachi.com>
*Cc:* keycloak-dev <keycloak-dev(a)lists.jboss.org>
*Subject:* [!]Re: [keycloak-dev] Override Refresh token lifespan per
client
I'm still not quite following what you are trying to achieve.
For authorization code flow it makes no sense at all to have different
session timeouts as it is by definition a shared SSO session. Different
security levels should be controlled things like step-up and authentication
timeout, not by having different session timeouts. Further, I'm not sure if
refresh token timeout should be configurable per-client here as end of the
day a new refresh token can easily be obtained as long as the session is
still active.
For client credentials grant where the server obtains tokens this may make
sense.
I'm not particularly found of introducing so many settings on a client.
It's difficult to setup and error prone. So this use-case needs to be
described properly and we need to find a decent solution to it. Simply
adding all these settings on a client may work for you, but I doubt others
would understand how and when to use them, and I think it can easily end up
resulting in a lot of error cases.
On Fri, 20 Sep 2019 at 08:40, TABATA,YOSHIYUKI <
yoshiyuki.tabata.jy(a)hitachi.com> wrote:
Hello,
In cloud-native application systems, there are various client applications
and those applications are not the same level (i.e. security level,
alliance level, development level). And generally, a realm manager or a
resource server manager wants to set a different timeout to tokens (access
token/refresh token) per client. For example, for a client which wants to
minimize authentication considering usability, we set the timeout of a
refresh token longer enough. For a client which wants to refresh tokens
periodically to mitigate the token interception attack, we set the timeout
of a refresh token according to the client requirement.
Currently, the timeout of an access token can be overridden per client.
However, the timeout of a refresh token (including offline token) cannot be
overridden per client.
We'd like to be able to override the timeout of a refresh token (including
offline token) per client.
We'd already tried to implement this just like access token lifespan
overriding, and create JIRA ticket and PR, but Stian recommended that we
should discuss this use case and how to implement in ML, so I opened this
thread.
For single sign-on purpose, it is useful to share sessions among clients
in a realm.
However, when we implement this, sessions are no longer shared among
clients depending on the settings. And this is useful for API management
purpose because, for API management purpose, tokens (= sessions) are
associated with each client, and should be managed per client.
What do you think about this feature? I would be very happy if you
community gives any kind of comment on that.
JIRA ticket is the following.
https://issues.jboss.org/browse/KEYCLOAK-10907
<
https://clicktime.symantec.com/3XksWm4odSS8VwXNrH1nE8Q7Vc?u=https%3A%2F%2...
>
PR is the following.
https://github.com/keycloak/keycloak/pull/6309
<
https://clicktime.symantec.com/3KpbzQn7GfmuzEjrULq3CKg7Vc?u=https%3A%2F%2...
>
Regards,
Yoshiyuki Tabata
Hitachi, Ltd.
_______________________________________________
keycloak-dev mailing list
keycloak-dev(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/keycloak-dev
<
https://clicktime.symantec.com/36KFRJRZcwj1bDfny5pnUeA7Vc?u=https%3A%2F%2...
>
_______________________________________________
keycloak-dev mailing list
keycloak-dev(a)lists.jboss.org
https://lists.jboss.org/mailman/listinfo/keycloak-dev