Apple's Heimdal impelmentation uses a number of utility functions for
allocating names and credentials, to avoid calling malloc or calloc directly.
Import them.
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().)
* check `ctx->gc_ctx` in `gss_inquire_context()`
* check `gm_inquire_cred != NULL` in `gss_inquire_context()`
* check `min_lifetime` in `gss_inquire_cred()`
* check `gm_inquire_cred_by_mech != NULL` in `gss_inquire_cred_by_mech()`
* set mech error in `gss_inquire_cred_by_oid()`
* don't clobber error in `gss_inquire_cred_by_oid()`
* don't pass NULL minor_status to `gss_krb5_free_lucid_sec_context()`
* allow NULL ccache in `gss_krb5_ccache_name()`
* NULL names OK in `_gss_find_mn()`
* allow empty names in `gss_import_name()` (removes `input_name_buffer` length
check). to support ANONYMOUS. in `gss_import_name()`, ignore mech name
import failure as long as it's possible to import the name in some other
mechanism
* better argument validation in `gss_export_sec_context()`
* in `gss_compare_name()`, check `mn2 != NULL`
* check `gss_add_oid_set_member()` return code in `gss_indicate_mechs()`
* in `gss_destroy_cred()`, set output cred handle to `GSS_C_NO_CREDENTIAL`
* cast size_t to OM_uint32 where required
Works for krb5 and SPNEGO mechanisms. Kerberos credentials are passed as
credential cache names, or if there are memory based credentials, inband in the protocol. This means that the credentials buffers must be keep secret.
As documented by IBM (they have the wrong prototype though)
and GGF (GSS-API Extensions) back in 2001
