[Freeipa-devel] [freeipa PR#298][comment] ipaldap: handle binary encoding option transparently
URL: https://github.com/freeipa/freeipa/pull/298 Title: #298: ipaldap: handle binary encoding option transparently frasertweedale commented: """ OK, let's just fix all the plugins / other routines that deal with the relevant attributes to explicitly read both `userCertificate` and `userCertificate;binary` and concat the results. I think there is a lot more we could and should do to improve usability w.r.t. these attributes but it will do for now. Closing this PR. """ See the full comment at https://github.com/freeipa/freeipa/pull/298#issuecomment-268508499 -- Manage your subscription for the Freeipa-devel mailing list: https://www.redhat.com/mailman/listinfo/freeipa-devel Contribute to FreeIPA: http://www.freeipa.org/page/Contribute/Code
[Freeipa-devel] [freeipa PR#298][comment] ipaldap: handle binary encoding option transparently
URL: https://github.com/freeipa/freeipa/pull/298 Title: #298: ipaldap: handle binary encoding option transparently jcholast commented: """ > If `ipaldap` is a generic LDAP client, it should obey the RFCs and always > transfer the relevant attributes (`userCertificate`, `cACertificate`, etc) > with the `;binary` encoding option, and it should expect to see it when > reading the relevant attributes from the server. No, it should respect whatever is defined on the server, otherwise it's not a generic LDAP client. If the server does something wrong, it has to be fixed there, on the server. The goal of `ipaldap` is not to make buggy or non-LDAPv3 (e.g. AD) servers look like they are LDAPv3-compliant, the goal is to interpret attributes according to the server-defined schema. > IMO `ipaldap` should handle this transparently because it is part of the LDAP > protocol. Nowhere in the RFCs is it mandated that a compliant client cannot request the attributes without the option, nor that it must not accept the attributes without the option in server responses. If this was true, it would have to be fixed in OpenLDAP libs anyway, not in `ipaldap`. > There is no 389DS-specific hack in my proposed change (but I'm curious about > what part of it you feel is). The part where you implicitly add the binary transfer option to attribute names (although not mandated on clients by any RFC) without knowing how the attribute types are defined on the server (although mandated only on attribute types with the certificate syntax by RFC 4523) . > This would also avoid inconsistent handling of relevant attributes between > different plugins, which is the situation we currently have. This is because of historical reasons (the original implementation of `host` and `service` plugins used `userCertificate` instead of `userCertificate;binary`) and will have to stay this way at least until all of the buggy 389 DS / IPA releases go out of support. > But apart from the inconsisency (which is a nusiance) we have a bigger > problem - in several plugins we specifically try to read `userCertificate`, > but a RFC 4522 compliant server (which 389DS is not now, but hopefully one > day will be) will always return `userCertificate;binary`. So, our current > code breaks if/when that happens. Furthermore, other RFC 4522-compliant > programs that correctly use the ;binary transfer encoding option to, e.g. > write certificates to user entries, will cause those certificates to be > unreadable by current IPA plugin code. This is not good enough. We can easily fix the plugins to read from `userCertificate;binary` in addition to `userCertificate`. We have to continue to write to `userCertificate` only though, because of backward compatibility with older servers. > 389DS does not behave correctly; it's treatment of `;binary` is wrong in > several ways, apart from the incorrect attribute syntax for relevant > attributes. Not enforcing `;binary` on attribute types with octet string syntax *is* correct. I was not trying to imply anything else. """ See the full comment at https://github.com/freeipa/freeipa/pull/298#issuecomment-268505078 -- Manage your subscription for the Freeipa-devel mailing list: https://www.redhat.com/mailman/listinfo/freeipa-devel Contribute to FreeIPA: http://www.freeipa.org/page/Contribute/Code
[Freeipa-devel] [freeipa PR#298][comment] ipaldap: handle binary encoding option transparently
URL: https://github.com/freeipa/freeipa/pull/298 Title: #298: ipaldap: handle binary encoding option transparently frasertweedale commented: """ @jcholast I disagree. If `ipaldap` is a generic LDAP client, it should obey the RFCs and always transfer the relevant attributes (`userCertificate`, `cACertificate`, etc) with the `;binary` encoding option, and it should expect to see it when reading the relevant attributes from the server. IMO `ipaldap` should handle this transparently because it is part of the LDAP protocol. There is no 389DS-specific hack in my proposed change (but I'm curious about what part of it you feel is). This would also avoid inconsistent handling of relevant attributes between different plugins, which is the situation we currently have. But apart from the inconsisency (which is a nusiance) we have a bigger problem - in several plugins we specifically try to read `userCertificate`, but a RFC 4522 compliant server (which 389DS is not now, but hopefully one day will be) will always return `userCertificate;binary`. So, our current code breaks if/when that happens. Furthermore, other RFC 4522-compliant programs that correctly use the `;binary` transfer encoding option to, e.g. write certificates to user entries, will cause those certificates to be unreadable by *current* IPA plugin code. This is not good enough. > Also note that the real bug in 389 DS is that it defines the attribute types > to use octet string syntax, rather than the certificate syntax as defined in > RFC 4523. It actually behaves correctly, not enforcing the binary transfer > option on attribute types with octet string syntax. 389DS does not behave correctly; it's treatment of `;binary` is wrong in several ways, apart from the incorrect attribute syntax for relevant attributes. """ See the full comment at https://github.com/freeipa/freeipa/pull/298#issuecomment-268457017 -- Manage your subscription for the Freeipa-devel mailing list: https://www.redhat.com/mailman/listinfo/freeipa-devel Contribute to FreeIPA: http://www.freeipa.org/page/Contribute/Code
[Freeipa-devel] [freeipa PR#298][comment] ipaldap: handle binary encoding option transparently
URL: https://github.com/freeipa/freeipa/pull/298 Title: #298: ipaldap: handle binary encoding option transparently frasertweedale commented: """ @jcholast I disagree. If `ipaldap` is a generic LDAP client, it should obey the RFCs and always transfer the relevant attributes (`userCertificate`, `cACertificate`, etc) with the `;binary` encoding option, and it should expect to see it when reading the relevant attributes from the server. IMO `ipaldap` should handle this transparently because it is part of the LDAP protocol. There is no 389DS-specific hack in my proposed change (but I'm curious about what part of it you feel is). This would also avoid inconsistent handling of relevant attributes between different plugins, which is the situation we currently have. But apart from the inconsisency (which is a nusiance) we have a bigger problem - in several plugins we specifically try to read `userCertificate`, but a RFC 4522 compliant server (which 389DS is not now, but hopefully one day will be) will always return `userCertificate;binary`. So, our current code breaks if/when that happens. Furthermore, other RFC 4522-compliant programs that correctly use the `;binary` transfer encoding option to, e.g. write certificates to user entries, will cause those certificates to be unreadable but *currenty* IPA code. This is not good enough. > Also note that the real bug in 389 DS is that it defines the attribute types > to use octet string syntax, rather than the certificate syntax as defined in > RFC 4523. It actually behaves correctly, not enforcing the binary transfer > option on attribute types with octet string syntax. 389DS does not behave correctly; it's treatment of `;binary` is wrong in several ways, apart from the incorrect attribute syntax for relevant attributes. """ See the full comment at https://github.com/freeipa/freeipa/pull/298#issuecomment-268457017 -- Manage your subscription for the Freeipa-devel mailing list: https://www.redhat.com/mailman/listinfo/freeipa-devel Contribute to FreeIPA: http://www.freeipa.org/page/Contribute/Code
[Freeipa-devel] [freeipa PR#298][comment] ipaldap: handle binary encoding option transparently
URL: https://github.com/freeipa/freeipa/pull/298 Title: #298: ipaldap: handle binary encoding option transparently jcholast commented: """ `ipaldap` is not the proper place to handle this - it implements a (almost) generic LDAP client, not a 389 DS client, and as such should not contain any 389 DS specific hacks. The premise is that the server gets exactly what the user of `ipaldap` requested, and the user gets exactly what the server returned. The binary transfer option is currently handled in code of the affected commands. The next layer below is `baseldap`, which is where the handling should be moved to make it generic for all commands. Also note that the real bug in 389 DS is that it defines the attribute types to use octet string syntax, rather than the certificate syntax as defined in RFC 4523. It actually behaves correctly, not enforcing the binary transfer option on attribute types with octet string syntax. """ See the full comment at https://github.com/freeipa/freeipa/pull/298#issuecomment-268451076 -- Manage your subscription for the Freeipa-devel mailing list: https://www.redhat.com/mailman/listinfo/freeipa-devel Contribute to FreeIPA: http://www.freeipa.org/page/Contribute/Code
