The Heimdal KDC does not add a PAC if an anonymous ticket was issued. As such,
test_context should not expect PAC naming attributes to be present if the
--anonymous option was passed. (This is irrelevant for now as GSS_C_ANON_FLAG
is not honored by the krb5 mechanism.)
Although not required to address bad code generation in
some versions of gcc 9 and 10, a coding style that requires
explicit comparison of the result to zero before use is
both clearer and would have avoided the generation of bad
code.
This change converts all use of cmp function usage from
```
if (strcmp(a, b) || !strcmp(c, d)) ...
```
to
```
if (strcmp(a, b) != 0 || strcmp(c, d)) == 0
```
for all C library cmp functions and related:
- strcmp(), strncmp()
- strcasecmp(), strncasecmp()
- stricmp(), strnicmp()
- memcmp()
Change-Id: Ic60c15e1e3a07e4faaf10648eefe3adae2543188
gss_{import,export}_sec_context did not work with partially accumulating
contexts, where the initial context token had not been completely accumulated,
Further, in gss_import_sec_context(), ctx->gc_input.value was not allocated to
a buffer sufficiently large to accumulate the target length.
The recently introduced gss_mg_name_to_oid() function supported looking up
dynamically loaded mechanisms by name, but did not support partial matches or
the legacy "Kerberos 5" name as supported by gss_name_to_oid().
Consolidate these into a single function, and also add support for dynamically
loaded mechanisms to gss_oid_to_name().
API behavior difference: the Kerberos mechanism is now referred to by "krb5"
rather tha "Kerberos 5", although for legacy compatibility gss_name_to_oid()
will recognize the old name. However, gss_oid_to_name() will return "krb5". The
anticipated impact is minimal as these are not standard GSS-APIs and do not
appear to have any public usage outside Heimdal.
Microsoft will sometimes split GSS tokens when they exceed a certain
size in some protocols. This is specified in
[MS-SPNG]: Simple and Protected GSS-API Negotiation
Mechanism (SPNEGO) Extension
https://winprotocoldoc.blob.core.windows.net/productionwindowsarchives/MS-SPNG/%5bMS-SPNG%5d.pdf
sections 3.1.5.4 to 3.1.5.9.
We extend gss_accept_sec_context() to recognise partial tokens and
to accumulate the fragments until an entire token is available to
be processed. If the entire token is not yet available,
GSS_S_CONTINUE_NEEDED is returned with a zero length output token.
This is specified in RFC2744 page 25-26 to indicate that no reply
need be sent.
We include updates to the test framework to test split tokens when
using SPNEGO.
Add support for SAnon, a simple key agreement protocol that provides no
authentication of initiator or acceptor using x25519 ECDH key exchange.
See doc/standardization/draft-howard-gss-sanon-xx.txt for a protocol
description.
SPNEGO was already using union creds. Now make the mechglue know about
it, delete all of the cred-related SPNEGO stubs that are now not called
(lib/gssapi/spnego/cred_stubs.c), and implement gss_get/set_neg_mechs()
by storing the OID set in the union cred.
This commit was essentially authored as much if not more by Luke Howard
<lukeh at padl.com> as much as by the listed author.
Add the --export-import-context flag to test_context, for validating that
security contexts round-trip through GSS_Export_sec_context() and
GSS_Import_sec_context().
An implementation of draft-zhu-negoex-04 for MIT Kerberos was developed in
2011. This has been recently integrated, with many fixes from Greg Hudson. This
commit ports it to Heimdal. The implementation has been interoperability tested
with MIT Kerberos and Windows, using the GSS EAP mechanism developed as part of
the Moonshot project.
The SPNEGO code was also updated to import the state machine from Apple which
improves mechListMIC processing and avoids discarding initial context tokens
generated during mechanism probing, that can be used for optimistic tokens.
Finally, to aid in testing, the GSS-API mechanism glue configuration file can
be changed using the environment variable GSS_MECH_CONFIG. This environment
variable name, along with the format of the configuration file, is compatible
with MIT (although it would be difficult for a single mechanism binary to
support both implementations).
Implement the GSS-API credential store API extensions defined by MIT here:
https://k5wiki.kerberos.org/wiki/Projects/Credential_Store_extensions
Note: we kill off gss_acquire_cred_ext() here. This was never a public API,
although mechanisms could have implemented it and I briefly used it in my
BrowserID prototype mechanism. gss_acquire_cred_ext_from() occupies the place
in the dispatch table where gss_acquire_cred_ext() used to, but this structure
was never visible outside Heimdal (i.e. it is only used by internal
mechanisms);
(Mechanisms that need to accept arbitrary key/value dictionaries from
applications should now implement gss_acquire_cred_from().)
The iovec encryption code doesn't handle 0 length iovecs correctly.
Instead of just skipping them, _krb5_evp_encrypt_iov_cts() will spin
on the 0 length iovec.
Modify the _krb5_evp_iov_cursor_expand helper so that iovec expansion
simply skips 0 length iovecs, and make _krb5_evp_iov_cursor_nextcrypt
do the same.
Original bug report and tests from Andrew Bartlett <abartlet@samba.org>
It isn't possible to use non-default credentials to init a context with
a mechanism for which the credential doesn't have an element. That's
exactly what was happening here. The code was left commented out to
describe how one might use SPNEGO with delegated credentials:
store them with gss_store_cred(), then acquire them back.
Bugs exposed by 61720a0:
- test_context --client-name=... --mech-type=ntlm ... fails;
- gss_acquire_cred() with desired_mech=NTLM and
desired_name==GSS_C_NO_NAME fails;
- gss_init_sec_context() with non-default cred handle calls the
mechanism even when the given cred handle has no element for the
requencet mechanism.
tests/gss/check-ntlm works by accident: gss_acquire_cred() with
desired_mechs==GSS_C_NO_OID_SET succeeds mostly because there are
Kerberos credentials available, and then the subsequent
gss_init_sec_context() call works because of the third bug described
above.
