Without this patch, the kgssapi uses detailed knowledge
of the internal context structure for Heimdal (up to vers 1.5).
It also does four upcalls to the gssd daemon to establish
a server side RPCSEC_GSS context.
This patch adds support for three new upcalls:
gss_init_sec_context_lucid_v1()
gss_accept_sec_context_lucid_v1()
gss_supports_lucid()
These are used to determine if the gssd can do the upcalls
and uses them to avoid needing detailed Heimdal knowledge
if they are supported.
gss_init_sec_context_lucid_v1() and
gss_accept_sec_context_lucid_v1() return the information
needed to complete the RPCSEC_GSS context.
They use gss_krb5_export_lucid_sec_context() to acquire
the information from the libraries. (MIT Kerberos supports
this and I believe newer versions of Heimdal does, as well).
This avoids the need for detailed knowledge about MIT's
internals and replaces the 2 or 4 (initiator or acceptor) upcalls
with a single upcall to create the RPCSEC_GSS context.
The old Heimdal (up to 1.5) support is left intact, but should
be removed whenever Heimdal 1.5 is removed from /usr/src.
The patch for the gssd daemon will be presented separately,
although both will need to be committed at the same time.