libsasl2-modules-gssapi-mit: buggy autoconf m4 script makes SASL's "keytab" option not work

[Russ Allbery]

Roberto C. Sánchez <roberto at connexer.com> writes:

> Sam, Russ, and Ben,

> I am going through some old bug reports against cyrus-sasl2, and I am
> curious as to your thoughts about the fix for #651308 as suggested by
> the submitter.

> On Thu, Dec 08, 2011 at 01:19:47AM +0800, Liu Yubao wrote:
>> 
>>    * What was the outcome of this action?
>>    * What outcome did you expect instead?
>> 
>> I feel it's better to fix sasl.m4 rather than directly change
>> plugins/gssapi.c to add more macros, maybe it's even better to just
>> change /usr/include/mit-krb5/gssapi/gssapi_krb5.h to use this macro:
>> #define krb5_gss_register_acceptor_identity
>> gsskrb5_register_acceptor_identity but this way breaks ABI
>> compatibility.

> Would the suggested change to MIT Kerberos be something that would be
> entertained by yourselves and by upstream?  Or is this something that
> needs to be fixed from within the cyrus-sasl2 package?

I think this needs to be fixed within the cyrus-sasl2 package.  Exposing
this as a function would mean adding a new function just to make the
Autoconf probe work, which doesn't seem like a good idea.  (The solution
that the bug reporter proposes definitely doesn't work, since as mentioned
that would change the GSS-API library API.)

I suspect that SASL is currently doing something like:

    AC_CHECK_FUNCS([gsskrb5_register_acceptor_identity])

The right solution is probably to also do:

    AC_CHECK_FUNCS([krb5_gss_regster_acceptor_identity])

and then use whichever one is found.

-- 
Russ Allbery (rra at debian.org)               <http://www.eyrie.org/~eagle/>