On Mon, Aug 19, 2013 at 3:48 PM, John Bradley <[email protected]> wrote:
> In OAuth and Connect there are cases where you are receiving tokens from > multiple sources. By allowing none as a alg option we can process signed > or unsigned tokens with the same basic handler by inspecting the first > segment. I note currently that while none has three segments the last > segment must be empty. I think that is sufficient to keep people from > becoming confused. > > Making it two segments will break existing parsers for no good reason. > No, there's a very good reason. Something that is not signed should not be accepted as a JSON Web Signature object. Acceptance of a JWS implies that the payload and protected headers were integrity protected from the signer; that is not true for "alg":"none". Also, it's not clear that this change will break existing parsers. For example, the NimbusDS parser would successfully parse a two-segment object as a "plain JWT" < https://bitbucket.org/nimbusds/nimbus-jose-jwt/src/ca58ff0ece35243aa6546583dffcd236dcea26d2/src/main/java/com/nimbusds/jwt/JWTParser.java?at=master > What we call it I am flexible about, if it is a unsigned JOSE object in > compact serialization i am fine. > I would also be completely fine with an unsigned "header + content" structure (though I don't think it adds any value). But it must be recognizably different from JWS. --Richard, who is honestly kind of floored that there's all this argument over a single "." character > > John B. > > On 2013-08-19, at 12:30 PM, Justin Richer <[email protected]> wrote: > > > I don't normally jump into the discussion on this list, but I've been > using the output of JOSE for quite some time now and am a committer on the > NimbusDS JOSE JWT library. However, with tonight's call coming up (which I > won't be able to make) I wanted to jump in and say that from my > perspective, alg:none makes a lot of sense. There's a need for being able > to send unsigned content with JOSE objects, and that's been pretty well > established by others on the list here. As an implementor, though, I think > it makes the most sense to have the unsigned content be parallel in > structure to the signed content. When reading a string and constructing > objects, our library parses the header and dispatches the parser based on > the "alg" parameter. > > > > And as Mike points out, alg:none has been in the spec as required to > implement for ages now, and it hasn't caused the horrible security holes > that people are predicting. > > > > -- Justin > > > > On 08/01/2013 07:23 AM, jose issue tracker wrote: > >> #36: Algorithm "none" should be removed > >> > >> > >> Comment (by [email protected]): > >> > >> And sure enough, working groups across the IETF are having to > explicitly > >> forbid the use of null ciphersuites. They provide empirical evidence > that > >> this design pattern is a bad idea. > >> > >> As I've pointed out before, you can add that verification algorithm, > but > >> you will not have a good time writing security considerations around > it. > >> Checking that you support "none" is not enough -- you have to check > that > >> *nothing* *else* in the header could possibly indicate that a different > >> signature algorithm should be used. > >> > >> So we have something that (1) causes a lot of spec work, (2) causes > >> security vulnerabilities under likely implementaiton designs, and (3) > has > >> no use case, and (4) will haunt us for years to come (how many times do > >> you want to write 'MUST NOT use "alg":"none"'?). Sounds like a recipe > for > >> success! > >> > > > > _______________________________________________ > > jose mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/jose > >
_______________________________________________ jose mailing list [email protected] https://www.ietf.org/mailman/listinfo/jose
