Read /etc/gss/mech if no mech.d/*.conf found

Always read /etc/gss/mech, even if globbing /etc/gss/mech.d/*.conf
doesn't work.  Doing this using GLOB_DOOFFS proved error-prone, so use
a simpler approach: factor out the per-pathname handling into a helper
function load_if_changed, call it with MECH_CONF before the glob, then
pass each glob result through the helper.

ticket: 7925
Remove DEBUG_ERROR_LOCATIONS support

It wasn't being used and it added too much complexity to the
error-handling functions.
Define k5_setmsg internal alias

This is just a shorter internal name for krb5_set_error_message.  The
full name is so long that we have to wrap error messages more than
we'd like.
Use k5_setmsg

Replace most calls to krb5_set_error_message with k5_setmsg for
brevity.  Leave alone plugin sources where we don't include k5-int.h
(mostly PKINIT).
Always include salt in LDAP KrbKey encoding

In the LDAP KDB module, ensure that every krb5_key_data we pass to
asn1_encode_sequence_of_keys includes a salt type, for compatibility
with the decoder in unpatched krb5 1.11 and 1.12.

This is not a behavior change by itself; since 1.7 the encoder has
always included a KrbKey salt field because it erroneously treats that
field as non-optional.  (Luckily, the encoded salt always happens to
have salt type 0 because krb5_key_data constructors start with zeroed
memory.)  The next commit will fix the encoder and decoder to properly
treat the KrbKey salt field as optional, so we need this change to
ensure that our encodings remain compatible.

Also fix the ASN.1 tests to set key_data_ver correctly for the sample
test key data.

ticket: 7919
Treat LDAP KrbKey salt field as optional

Per the ASN.1 definition, the KrbKey salt field is optional.  Since
1.7, we have been treating it as mandatory in the encoder; since 1.11,
we have been treating it as mandatory in the decoder.  Mostly by luck,
we have been encoding a salt type of 0 when key_data_ver is 1, but we
really should not be looking at key_data_type[1] or key_data_length[1]
in this situation.  Treat the salt field as optional in the encoder
and decoder.  Although the previous commit ensures that we continue to
always encode a salt (without any dangerous assumptions about
krb5_key_data constructors), this change will allow us to decode key
data encoded by 1.6 without salt fields.

This also fixes issue #7918, by properly setting key_data_ver to 2 if
a salt type but no salt value is present.  It is difficult to get the
decoder to actually assign 2 to key_data_ver just because the salt
field is there, so take care of that in asn1_decode_sequence_of_keys.

Adjust kdbtest.c to match the new behavior by setting key_data_ver to
2 in both test keys.

ticket: 7919
target_version: 1.12.2
tags: pullup
Do not loop on add_cred_from and other new methods

Several new GSS-API methods were added but GSSAPI_ADD_METHOD was
called to add them rather than GSSAPI_ADD_METHOD_NOLOOP.  This means
that the implementation from the GSS-API mechglue would be used if the
mechanism had no implementation.  As a result, the mechglue will call
into itself exhausting the call stack in an endless loop when one of
these methods is called.

ticket: 7926
target_version: 1.12.2
tags: pullup
In KDC, log client principal in bad header ticket

Fix KDC logging to include client principal in TGS_REQ logging even
during error conditions such as "Ticket expired".  As long as the
TGS_REQ can be decrypted and the client principal is available, it
should be included in the log, regardless of other errors which might
be detected.

krb5_rd_req_decoded and krb5_rd_req_decoded_anyflag (not public
interfaces) now leave the decrypted ticket in req->ticket->enc_part2
on success or failure, if the ticket was successfully decrypted.  This
does not affect the behavior of krb5_rd_req.

[ghudson@mit.edu: removed extraneous change, added commit message
summary and description of internal API change, fixed possible memory
leak, removed comment and #if 0 code block of purely historical
interest]

ticket: 7910
Add test for KDC client logging

Add a test case which performed a TGS request with an expired ticket
and checks that the client principal is logged.

ticket: 7910
Simplify ticket retrieval from AP-REQs

After krb5_rd_req_decoded or krb5_rd_req_decoded_anyflag, the ticket
(with enc_part2 if we could decrypt it) is accessible via
request->ticket; there is no need to copy it.  Stop using the ticket
parameter of those functions.  Where we need to save the ticket beyond
the lifetime of the krb5_ap_req, steal the pointer before freeing the
request.
Add missing profile functions to libkrb5 exports

profile_flush_to_buffer, profile_flush_to_file, profile_free_buffer,
profile_init_flags, and profile_init_vtable are all public profile
functions, but are inaccessible to libkrb5 applications on some
platforms because they were never added to the export list.  Add them
now.

(libprofile functions have never been part of the Windows DLL export
list, so do not change krb5_32.def at this time.)

ticket: 7930 (new)
target_version: 1.12.2
tags: pullup
Remove stub pkinit_win2k code

As contributed, the PKINIT module contained code to read the
pkinit_win2k variable, but never used it.  Get rid of the structure
field and the code to populate it.
Do not document pkinit_win2k

This variable was never used in the PKINIT code as it was contributed;
there was only code to read its value.

ticket: 7932 (new)
target_version: 1.12.2
tags: pullup
Simplify and fix k5_check_cert_address

Get rid of the address union.  Store the result of get_cert_cn in a
signed variable so we can meaningfully check for negative results.
Make get_cert_cn return int for consistency with
X509_NAME_get_text_by_NID and its two callers.

Also add an emacs mode line to the top of the file.

ticket: 7929
Improve PKINIT certificate documentation

Describe how to use a commercially-issued server certificate for
anonymous PKINIT.  Separate the KDC and client configuration
instructions so that the steps necessary for anonymous PKINIT are not
combined with the additional steps necessary for regular PKINIT.
Describe kpServerAuth as the EKU used in commercially issued server
certificates, not as the value used by Microsoft (which does not
appear to be true according to [MS-PKCA]).

ticket: 7931 (new)
target_version: 1.12.2
tags: pullup
Remove PKINIT longhorn compatibility option

Remove the PKINIT Windows Server 2008 beta compatibility code
conditionalized under the "longhorn" variable.  It is not required to
interoperate with any released version of Windows.

ticket: 7934 (new)
Unlocked db2 KDB iteration

Try to make an optional db2 iterator that unlocks (and therefore
closes) the KDB between iterations, to allow large KDBs to be dumped
without blocking writes for a long time.

This is a hackish proof of concept.  It won't work for all consumers
of db_iterate, especially ones that need to hold other locks while
iterating.