Re: [keycloak-dev] Pairwise Subject Identifier

Sounds good. I'll look into it and see what I can do. Possibly during next week. :) On Tue, 23 Aug 2016 at 15:38 Marek Posolda <mposolda(a)redhat.com <mailto:mposolda@redhat.com>> wrote: We discussed it with Stian a bit and we discussed to: - Implement as protocolMapper - There will be possibility to configure "salt" as parameter to protocolMapper. It may not be mandatory parameter. If it's used, then client will use it as salt, otherwise salt will be generated. This allows the use-case you mentioned. You can use same salt for clients x,y,z but different salt for clients m,n. If you let generate salt, then the subject identifiers will be really unique just to the particular client. - We need to validate sector_identifier_uri during create/update of protocolMapper, but also during update of client. Otherwise someone can register sector_identifier_uri and register the client with valid redirect_uris (for example URLs "http://good-host/url1" <http://good-host/url1> "http://good-host/url2" <http://good-host/url2> , which are both specified under sector_identifier_uri ) but then later update just the client redirect_uris to "http://evil-host/url1" <http://evil-host/url1> . Basically he will be able to update redirect_uris to anything he wants regardless of redirect_uris under sector_identifier_uri, so the whole validation will be bypassed. For updating client, I've just sent PR, which adds RealmModel.ClientUpdatedEvent . You can register to that event similarly like https://github.com/keycloak/keycloak/blob/master/server-spi/src/main/java... . The creation/update listener for protocolMapper doesn't yet exists, however we are likely going to refactor protocolMapper to generic component, which will have validation support. But that will be likely available in few weeks, so for now, we can add something temporary for protocolMappers similar to what is available for example for UserFederationMapperFactory (See https://github.com/keycloak/keycloak/blob/master/services/src/main/java/o... ) Martin, will you have some time to eventually look into this and send PR ? Marek On 23/08/16 14:25, Martin Hardselius wrote: > Let's say we want to force all of our client to use pairwise > subs, but a single "merchant" needs to implement several clients > where subs should remain the same for all those clients. > > Merchant A > - client x > - client y > - client z > > Merchant B > - client m > - client n > > You can assume the sector_identifiers are the same across all > clients owned by a merchant > > It should not be possible to correlate activities between > Customer A and Customer B (at least not from their side). They > should, however, be able to correlate user activities between > their own clients. > > Which implementation of pairwise subs is better suited for > supporting this scenario? I'm leaning towards the protocol mapper > solution. It should be easier to create custom mappers with > merchant-wide configuration (e.g salts). > > On Mon, 22 Aug 2016 at 22:40 Marek Posolda <mposolda(a)redhat.com > <mailto:mposolda@redhat.com>> wrote: > > The question is, should we really introduce another SPI for > that? Doesn't it mean uneccessary complexity? Also add the > new options directly to the client for the feature, which is > likely interesting just for quite limited amount of people? > > IMO it's fine if this is implemented as protocolMapper? > > Few thoughts: > - We can have abstract superclass like > AbstractPairwiseSubGeneratorMapper . The subclasses will just > need to implement method "generateSub" . We can have just one > concrete impl, which will use SHA-256( sector_identifier || > local_sub || salt ) > > - The sector_identifier_uri will be a configuration option of > this protocolMapper implementation. > > - If protocolMapper is not added to client, the client will > just use the public subjects. By default it's not added, > which ensures backwards compatibility and public subjects by > default. Note that with this approach, we don't even need > subject_type option on the client. > > - The salt can be generated lazily at the first time when > mapper is used. > > - The validation can be done at the moment, when > protocolMapper is going to be created/updated. Right now, we > don't have validation callback during protocolMapper > creation/update. However Bill is going to add support for > that into generic componentModel. So if we're going to > refactor protocolMapper to use the new generic component > model, we will have validation callback available to > protocolMapper SPI. The validation will fail if array of > redirect_uri from sector_identifier_uri doesn't contain the > uris from redirect_uri of particular client (including > wildcards etc). > > - If client is updated and it's redirect_uri are changed, we > won't be able to catch this, however this is not strictly > required per specs per my understanding. At least the dynamic > client registration specs sais [1] > > "The values registered in redirect_uris MUST be included in > the elements of the array, or registration MUST fail. This > MUST be validated at registration time; there is no > requirement for the OP to retain the contents of this JSON > file or to retrieve or revalidate its contents in the future. " > > [1] > http://openid.net/specs/openid-connect-registration-1_0.html#SectorIdenti... > > > Marek > > > On 22/08/16 15:50, Martin Hardselius wrote: >> Ok, thanks for the clarification. >> >> Where would it make sense to put the >> PairwiseSubGeneratorSpi? Which package, that is? >> >> On Mon, 22 Aug 2016 at 14:51 Stian Thorgersen >> <sthorger(a)redhat.com <mailto:sthorger@redhat.com>> wrote: >> >> On 22 August 2016 at 14:16, Martin Hardselius >> <martin.hardselius(a)gmail.com >> <mailto:martin.hardselius@gmail.com>> wrote: >> >> "IMO it's sufficient to document the algorithm to >> create the sub, which should make it clear that the >> origin in the redirect uri will affect the sub." >> >> Reasonable. :) >> >> "One client could also have multiple redirect uris >> with different origins so could get different sub's >> generated depending on the redirect uri used." >> >> That case is probably caught by >> [...] If there are multiple hostnames in the >> registeredredirect_uris, the Client MUST register >> asector_identifier_uri. [...] >> >> >> Yes, but I meant from a documentation perspective. It >> should be clear from the documentation that is the case. >> >> >> On Mon, 22 Aug 2016 at 10:42 Stian Thorgersen >> <sthorger(a)redhat.com <mailto:sthorger@redhat.com>> >> wrote: >> >> IMO it's sufficient to document the algorithm to >> create the sub, which should make it clear that >> the origin in the redirect uri will affect the >> sub. One client could also have multiple >> redirect uris with different origins so could >> get different sub's generated depending on the >> redirect uri used. >> >> On 22 August 2016 at 09:58, Martin Hardselius >> <martin.hardselius(a)gmail.com >> <mailto:martin.hardselius@gmail.com>> wrote: >> >> Sounds fair enough. >> >> What about the case where you don't provide >> a sector_identifier_uri, set up a single >> redirect uri on myhost and then later go on >> to change that redirect uri to something on >> myotherhost? That would change the >> sector_identifier and subsequently all the >> user subs. Do we protect against such >> "mistakes" or do we warn people (in the docs >> and/or admin gui) that it's not a good idea >> to do that? >> >> On Mon, 22 Aug 2016 at 09:38 Stian >> Thorgersen <sthorger(a)redhat.com >> <mailto:sthorger@redhat.com>> wrote: >> >> We need to follow the spec and verify >> that sector_identifier_uri points to a >> URL that contains the corresponding >> URIs. As an enhancement we could support >> wildcards in the JSON returned >> by sector_identifier_uri. For example if >> it returns: >> >> [https://www.mydomain.com/*, >> https://www.myotherdomain.com/* ] >> >> A client with the redirect uri >> 'https://www.myotherdomain.com/myapp' >> would work >> >> On 18 August 2016 at 15:09, Martin >> Hardselius <martin.hardselius(a)gmail.com >> <mailto:martin.hardselius@gmail.com>> wrote: >> >> Speaking of subject_identifier_uri >> >> From the spec: >> >> "When asector_identifier_uriis >> provided, the host component of that >> URL is used as the Sector Identifier >> for the pairwise identifier >> calculation. The value of >> thesector_identifier_uriMUST be a >> URL using thehttpsscheme that points >> to a JSON file containing an array >> ofredirect_urivalues. The values of >> the registeredredirect_urisMUST be >> included in the elements of the array." >> >> What's your stance on sanity/health >> checking the sector_identifier_uri? >> URI validation is one thing, but >> should we also make a request to the >> uri in order to validate the response? >> >> The spec also mentions that the >> sector_identifier_uri isn't strictly >> required if a client has all it's >> redirect_uris under the same domain. >> How do we deal with changes to >> clients if the sector_identifier_uri >> isn't required for enabling pairwise >> subs? >> >> Example: >> >> I create a client, enabling pairwise >> subs. Valid redirect_uris are [ >> https://www.mydomain.com/* ]. The >> sector_identifier would be mydomain. >> >> Later on, I update the redirect_uris >> to [https://www.mydomain.com/*, >> https://www.myotherdomain.com/* ] Do we >> >> * keep the old sector_identifier, or >> * reject the update, or >> * allow the update if a valid >> subject_identifier_uri is provided >> at mydomain, or >> * just allow it and let the client >> devs deal with the consequences, or >> * take some other path you can think >> of ? >> >> Having the sector_identifier_uri as >> a hard requirement seems safer, but >> it's also means more work >> implementing a client. Leaving it >> optional is a lot more scary. >> >> >> On Thu, 18 Aug 2016 at 10:45 Stian >> Thorgersen <sthorger(a)redhat.com >> <mailto:sthorger@redhat.com>> wrote: >> >> Makes sense to make this >> pluggable. The default should >> probably SHA-256( >> sector_identifier || local_sub >> || salt ). >> >> We would love a PR for this, but >> there's a few bits required: >> >> * OIDC clients need option for >> subject type and >> sector_identifier_uri. If not >> set it should default to public >> so existing clients continue to >> work. These options can just be >> set as client attributes so >> there's no need to update db schema >> * Admin console update for the above >> * PairwiseSubGeneratorSpi and >> default implementation >> * Generation of salt for >> clients. This should be done >> when a client sets subject type >> to pairwise >> * Tests and docs >> >> I'd say the >> PairwiseSubGeneratorSpi >> signature should probably be: >> >> * public String >> getPairwiseSub(UserModel user, >> ClientModel client) >> >> It might even be an option to >> let the >> default PairwiseSubGenerator >> provider create the salt and >> store it as an attribute on the >> client, making that part >> pluggable as well. >> >> On 17 August 2016 at 15:59, >> Martin Hardselius >> <martin.hardselius(a)gmail.com >> <mailto:martin.hardselius@gmail.com>> >> wrote: >> >> I'm going to bump this, as I >> want to continue the >> discussion/provide some input. >> >> Does it make sense to >> support more than type of >> pairwise subject identifier >> generator? E.g through a >> PairwiseSubGeneratorSpi? >> >> Let's say I want to generate >> the pairwise sub as a salted >> hash: sub = SHA-256( >> sector_identifier || >> local_sub || salt ) >> To me, it makes sense to >> allow for per-client salts. >> These salts should probably >> be generated and persisted >> during client creation. >> Thoughts? >> >> On Fri, 12 Aug 2016 at 09:57 >> Martin Hardselius >> <martin.hardselius(a)gmail.com >> <mailto:martin.hardselius@gmail.com>> >> wrote: >> >> Thank you for your >> response. Did not see >> that ticket before. >> Great news! >> >> I looked into using >> protocol mappers to >> achieve this, and while >> it would work I'm >> worried that once >> KEYCLOAK-3422 has been >> resolved and included in >> a proper release we >> would run into migration >> issues if the method >> used for calculating >> "native" pairwise subs >> is different from what >> we implement. Clients >> could loose / be forced >> to re-register all their >> users if we decide to >> switch. The example >> methods in the spec are >> just that. Examples. >> Maybe the method/alg for >> computing the pairwise >> sub should be pluggable? >> >> -- >> Martin >> >> On Thu, 11 Aug 2016 at >> 17:15 Marek Posolda >> <mposolda(a)redhat.com >> <mailto:mposolda@redhat.com>> >> wrote: >> >> Sorry for late >> response. >> >> We have JIRA created >> for that. You can >> possibly add >> yourself as a >> watcher. See >> https://issues.jboss.org/browse/KEYCLOAK-3422 >> >> Maybe an alternative >> for you is to use >> protocolMappers. >> That should allow >> you to "construct" >> the token for >> particular client >> exactly how you want >> and also use the >> different value for >> "sub" claim. >> >> Another possibility >> is, to handle this >> on adapter side. We >> already have an >> adapter option >> "principal-attribute", >> which specifies that >> application will see >> the different >> attribute instead of >> "sub" as subject. >> For example when in >> appllication you >> call >> "httpServletRequest.getRemoteUser()" >> it will return >> "john" instead of >> "123456-unique-johns-uuid" >> . See >> https://keycloak.gitbooks.io/securing-client-applications-guide/content/v... >> >> Hopefully some of >> the options can be >> useful for you? >> >> Marek >> >> >> On 02/08/16 14:13, >> Martin Hardselius wrote: >>> Me and my team are >>> working towards >>> getting Keycloak, >>> customized for our >>> needs, into >>> production but >>> we've identified >>> the need for >>> Pairwise Subject >>> Identifiers as we >>> don't want to >>> expose internal >>> user ids. >>> >>> Right now, the only >>> subject_types_supported >>> seems to be >>> "public". Are there >>> any near-future >>> plans to include >>> "pairwise"? Can we >>> pitch in with a PR >>> to make this happen >>> as soon as possible? >>> >>> Links to relevant >>> sections in the spec: >>> >>> http://openid.net/specs/openid-connect-core-1_0.html#SubjectIDTypes >>> http://openid.net/specs/openid-connect-core-1_0.html#PairwiseAlg >>> >>> -- >>> Martin >>> >>> >>> _______________________________________________ >>> keycloak-dev mailing list >>> keycloak-dev(a)lists.jboss.org >>> <mailto:keycloak-dev@lists.jboss.org> >>> https://lists.jboss.org/mailman/listinfo/keycloak-dev >> >> >> _______________________________________________ >> keycloak-dev mailing list >> keycloak-dev(a)lists.jboss.org >> <mailto:keycloak-dev@lists.jboss.org> >> https://lists.jboss.org/mailman/listinfo/keycloak-dev >> >> >> >> >