Jason
Do you anticipate any backward compatibility issues with existing custom
implementation of the authorization interface/plugins?
Thanks
Bosco
On 8/25/17, 3:22 PM, "Jason Gustafson" <ja...@confluent.io> wrote:
No problem. I'll add a note to the KIP to emphasize that we will use the
same object built by the KafkaPrincipalBuilder in the Session object passed
to the authorizer.
-Jason
On Fri, Aug 25, 2017 at 3:17 PM, Mayuresh Gharat <gharatmayures...@gmail.com
> wrote:
> Perfect.
> As long as there is a way we can access the originally created Principal
in
> the Authorizer, it would solve the KIP-111 issue.
>
> This is really helpful, thanks again.
>
> Thanks,
>
> Mayuresh
>
> On Fri, Aug 25, 2017 at 3:13 PM, Jason Gustafson <ja...@confluent.io>
> wrote:
>
> > Hi Mayuresh,
> >
> > To clarify, the intention is to use the KafkaPrincipal object built by
> the
> > KafkaPrincipalBuilder inside the Session. So we would remove the logic
to
> > construct a new KafkaPrincipal using only the name from the Principal.
> Then
> > it should be possible to pass the `AuthzPrincipal` to the underlying
> > library through the `Extended_Plugged_In_Class` as you've suggested
> above.
> > Is that reasonable for this use case?
> >
> > Thanks,
> > Jason
> >
> >
> > On Fri, Aug 25, 2017 at 2:44 PM, Mayuresh Gharat <
> > gharatmayures...@gmail.com
> > > wrote:
> >
> > > Hi Jason,
> > >
> > > Thanks for the replies.
> > >
> > > I think it would be better to discuss with an example that we were
> trying
> > > to address with KIP-111 and see if the current mentioned solution
would
> > > address it.
> > >
> > > Let's consider a third party library called authz_lib that is provided
> by
> > > some Security team at some company.
> > >
> > > - When we call authz_lib.createPrincipal(X509_cert), it would
> return
> > an
> > > AuthzPrincipal that implements Java.Security.Principal.
> > >
> > >
> > > - The authz_lib also provides an checkAccess(....) call that takes
> in
> > 3
> > > parameters :
> > > - authz_principal
> > > - operation type ("Read", "Write"...)
> > > - resource (for simplicity lets consider it as a TopicName)
> > >
> > >
> > > - The AuthzPrincipal looks like this :
> > >
> > > class AuthzPrincipal implements java.security.Principal
> > > {
> > > String name;
> > > String field1;
> > > Object field2;
> > > Object field3;
> > > .....//Some third party logic......
> > > }
> > >
> > >
> > > - In PrincipalBuilder.buildPrincipal() would return AuthzPrincipal
> as
> > > follows :
> > >
> > > public Principal buildPrincipal(...)
> > > {
> > > ......
> > > X509Certificate x509Cert = session.getCert(..);
> > > return authz_lib.createPrincipal(x509Cert);
> > > }
> > >
> > >
> > > - The custom Authorizer (lets call it CustomAuthzAuthorizer), we
> would
> > > use the checkAccess() function provided by the authz_lib as follows
> :
> > >
> > > public class CustomAuthzAuthorizer implements Authorizer
> > > {
> > > .........
> > > public boolean authorize(.....)
> > > {
> > > AuthzPrincipal authz_principal = (AuthzPrincipal)
> > > session.getPrincipal();
> > > return authz_lib.checkAccess(authz_principal, "Read", "topicX");
> > > }
> > > ..........
> > > }
> > >
> > >
> > > - The issue with current implementation is that in
> > > processCompletedReceives() in SocketServer we create a
> KafkaPrincipal
> > > that just extracts the name from AuthzPrincipal as follows :
> > >
> > > session = RequestChannel.Session(new
> > > KafkaPrincipal(KafkaPrincipal.USER_TYPE,
> > > *openOrClosingChannel.principal.getName*),
> > > openOrClosingChannel.socketAddress)
> > >
> > > So the "AuthzPrincipal authz_principal = (AuthzPrincipal)
> > > session.getPrincipal()" call in the CustomAuthzAuthorizer would error
> > > out because we are trying to cast a KafkaPrincipal to AuthzPrincipal.
> > >
> > >
> > >
> > > In your reply when you said that :
> > >
> > > The KIP says that a user can have a class that extends KafkaPrincipal.
> > > Would this extended class be used when constructing the Session object
> > > in the SocketServer instead of constructing a new KafkaPrincipal?
> > >
> > > Yes, that's correct. We want to allow the authorizer to be able to
> > leverage
> > > > additional information from the authentication layer.
> > >
> > >
> > > Would it make sense to make this extended class pluggable and when
> > > constructing the Session object in SocketServer check if a plugin is
> > > defined and use it and if not use the default KafkaPrincipal something
> > like
> > > :
> > >
> > > if (getConfig("principal.pluggedIn.class").isDefined())
> > > //"principal.pluggedIn.class"
> > > is just an example name for the config
> > > {
> > > session = RequestChannel.Session(*Extended_Plugged_In_Class*,
> > > openOrClosingChannel.socketAddress)
> > > }
> > > else
> > > {
> > > session = RequestChannel.Session(new KafkaPrincipal(KafkaPrincipal.
> > > USER_TYPE,
> > > *openOrClosingChannel.principal.getName*),
> > > openOrClosingChannel.socketAddress)
> > > }
> > >
> > > This would solve the issue above as follows :
> > >
> > > We can have something like :
> > > public class Extended_Plugged_In_Class extends KafkaPrincipal
> > > {
> > > AuthzPrincipal authzPrincipal;
> > >
> > > public Extended_Plugged_In_Class(....., AuthzPrincipal principal)
> > > {
> > > super(...);
> > > authzPrincipal = principal;
> > >
> > > }
> > >
> > > ......
> > >
> > > public AuthzPrincipal getAuthzPrincipal()
> > > {
> > > return authzPrincipal;
> > > }
> > > }
> > >
> > > In the CustomAuthzAuthorizer we could do something like :
> > >
> > > public class CustomAuthzAuthorizer implements Authorizer
> > > {
> > > .........
> > > public boolean authorize(.....)
> > > {
> > > Extended_Plugged_In_Class extended_Kafka_Principal =
> > > (Extended_Plugged_In_Class)
> > > session.getPrincipal();
> > > AuthzPrincipal authz_principal =
> > > extended_Kafka_Principal.getAuthzPrincipal();
> > > return authz_lib.checkAccess(authz_principal, "Read", "topicX");
> > > }
> > > ..........
> > > }
> > >
> > >
> > > Thanks,
> > >
> > > Mayuresh
> > >
> > > On Fri, Aug 25, 2017 at 11:53 AM, Jason Gustafson <ja...@confluent.io>
> > > wrote:
> > >
> > > > Hey Mayuresh,
> > > >
> > > > Thanks for the comments.
> > > >
> > > > - The KIP says that a user can have a class that extends
> > > KafkaPrincipal.
> > > > > Would this extended class be used when constructing the Session
> > > object
> > > > > in
> > > > > the SocketServer instead of constructing a new KafkaPrincipal?
> > > >
> > > >
> > > > Yes, that's correct. We want to allow the authorizer to be able to
> > > leverage
> > > > additional information from the authentication layer.
> > > >
> > > > - The KIP says "A principal is always identifiable by a
principal
> > > type
> > > > > and a name. Nothing else should ever be required." This might
> not
> > be
> > > > > true
> > > > > always, right? For example, we might have a custom third party
> ACL
> > > > > library
> > > > > that creates a custom Principal from the passed in cert (this
is
> > > done
> > > > in
> > > > > PrincipalBuilder/KafkaPrincipalBuilder) and the custom
> Authorizer
> > > > might
> > > > > use this third party library to authorize using this custom
> > > Principal
> > > > > object. The developer who is implementing the Kafka Authorizer
> > > should
> > > > > not be caring about what the custom Principal would look like
> and
> > > its
> > > > > details, since it will just pass it to the third party library
> in
> > > > Kafka
> > > > > Authorizer's authorize() call.
> > > >
> > > >
> > > > I'm not sure I understand this. Are you saying that the authorizer
> and
> > > > principal builder are implemented by separate individuals? If the
> > > > authorizer doesn't understand how to identify the principal, then it
> > > > wouldn't work, right? Maybe I'm missing something?
> > > >
> > > > Let me explain how I see this. The simple ACL authorizer that Kafka
> > ships
> > > > with understands user principals as consisting of a type and a name.
> > Any
> > > > principal builder that follows this assumption will work with the
> > > > SimpleAclAuthorizer. In some cases, the principal builder may
provide
> > > > additional metadata in a KafkaPrincipal extension such as user
groups
> > or
> > > > roles. This information is not needed to identify the user
principal,
> > so
> > > > the builder is still compatible with the SimpleAclAuthorizer. It
> would
> > > also
> > > > be compatible with a RoleBasedAuthorizer which understood how to use
> > the
> > > > role metadata provided by the KafkaPrincipal extension. Basically
> what
> > we
> > > > would have is a user principal which is related to one or more role
> > > > principals through the KafkaPrincipal extension. Both user and role
> > > > principals are identifiable with a type and a name, so the ACL
> command
> > > tool
> > > > can then be used (perhaps with a custom authorizer) to define
> > permissions
> > > > in either case.
> > > >
> > > > On the other hand, if a user principal is identified by more than
> just
> > > its
> > > > name, then it is not compatible with the SimpleAclAuthorizer. This
> > > doesn't
> > > > necessarily rule out this use case. As long as the authorizer and
the
> > > > principal builder both agree on how user principals are identified,
> > then
> > > > they can still be used together. But I am explicitly leaving out
> > support
> > > in
> > > > the ACL command tool for this use case in this KIP. This is mostly
> > about
> > > > clarifying what is compatible with the authorization system that
> Kafka
> > > > ships with. Of course we can always reconsider it in the future.
> > > >
> > > > Thanks,
> > > > Jason
> > > >
> > > > On Fri, Aug 25, 2017 at 10:48 AM, Mayuresh Gharat <
> > > > gharatmayures...@gmail.com> wrote:
> > > >
> > > > > Hi Jason,
> > > > >
> > > > > Thanks a lot for the KIP and sorry for the delayed response.
> > > > >
> > > > > I had a few questions :
> > > > >
> > > > >
> > > > > - The KIP says that a user can have a class that extends
> > > > KafkaPrincipal.
> > > > > Would this extended class be used when constructing the Session
> > > object
> > > > > in
> > > > > the SocketServer instead of constructing a new KafkaPrincipal?
> > > > >
> > > > >
> > > > > - The KIP says "A principal is always identifiable by a
> principal
> > > type
> > > > > and a name. Nothing else should ever be required." This might
> not
> > be
> > > > > true
> > > > > always, right? For example, we might have a custom third party
> ACL
> > > > > library
> > > > > that creates a custom Principal from the passed in cert (this
is
> > > done
> > > > in
> > > > > PrincipalBuilder/KafkaPrincipalBuilder) and the custom
> Authorizer
> > > > might
> > > > > use this third party library to authorize using this custom
> > > Principal
> > > > > object. The developer who is implementing the Kafka Authorizer
> > > should
> > > > > not be caring about what the custom Principal would look like
> and
> > > its
> > > > > details, since it will just pass it to the third party library
> in
> > > > Kafka
> > > > > Authorizer's authorize() call.
> > > > >
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Mayuresh
> > > > >
> > > > >
> > > > > On Thu, Aug 24, 2017 at 10:21 AM, Mayuresh Gharat <
> > > > > gharatmayures...@gmail.com> wrote:
> > > > >
> > > > > > Sure.
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > Mayuresh
> > > > > >
> > > > > > On Wed, Aug 23, 2017 at 5:07 PM, Jun Rao <j...@confluent.io>
> wrote:
> > > > > >
> > > > > >> Hi, Mayuresh,
> > > > > >>
> > > > > >> Since this KIP covers the requirement in KIP-111, could you
> review
> > > it
> > > > > too?
> > > > > >>
> > > > > >> Thanks,
> > > > > >>
> > > > > >> Jun
> > > > > >>
> > > > > >>
> > > > > >> On Tue, Aug 22, 2017 at 3:04 PM, Jason Gustafson <
> > > ja...@confluent.io>
> > > > > >> wrote:
> > > > > >>
> > > > > >>> Bump. I'll open a vote in a few days if there are no comments.
> > > > > >>>
> > > > > >>> Thanks,
> > > > > >>> Jason
> > > > > >>>
> > > > > >>> On Sat, Aug 19, 2017 at 12:28 AM, Ismael Juma <
> ism...@juma.me.uk
> > >
> > > > > wrote:
> > > > > >>>
> > > > > >>> > Thanks for the KIP Jason. It seems reasonable and cleans up
> > some
> > > > > >>> > inconsistencies in that area. It would be great to get some
> > > > feedback
> > > > > >>> from
> > > > > >>> > Mayuresh and others who worked on KIP-111.
> > > > > >>> >
> > > > > >>> > Ismael
> > > > > >>> >
> > > > > >>> > On Thu, Aug 17, 2017 at 1:21 AM, Jason Gustafson <
> > > > ja...@confluent.io
> > > > > >
> > > > > >>> > wrote:
> > > > > >>> >
> > > > > >>> > > Hi All,
> > > > > >>> > >
> > > > > >>> > > I've added a new KIP to improve and extend the principal
> > > building
> > > > > API
> > > > > >>> > that
> > > > > >>> > > Kafka exposes:
> > > > > >>> > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-
> > > > > >>> > > 189%3A+Improve+principal+builder+interface+and+add+
> > > > > support+for+SASL
> > > > > >>> > > .
> > > > > >>> > >
> > > > > >>> > > As always, feedback is appreciated.
> > > > > >>> > >
> > > > > >>> > > Thanks,
> > > > > >>> > > Jason
> > > > > >>> > >
> > > > > >>> >
> > > > > >>>
> > > > > >>
> > > > > >>
> > > > > >
> > > > > >
> > > > > > --
> > > > > > -Regards,
> > > > > > Mayuresh R. Gharat
> > > > > > (862) 250-7125
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > -Regards,
> > > > > Mayuresh R. Gharat
> > > > > (862) 250-7125
> > > > >
> > > >
> > >
> > >
> > >
> > > --
> > > -Regards,
> > > Mayuresh R. Gharat
> > > (862) 250-7125
> > >
> >
>
>
>
> --
> -Regards,
> Mayuresh R. Gharat
> (862) 250-7125
>
