lib/krb5: keep a copy of config etypes in the context

When reading configuration file, keep an extra copy of
the encryption types, and use this when resetting the
encryption types to default.

GSSAPI always resets the enctypes to default before obtaining
a TGS, because the enctypes might have previously altered,
so this prevents changing the etypes from the configured ones
to the full set of supported etypes.

Signed-off-by: Uri Simchoni <uri@samba.org>

lib/krb5/krb5_locl.h

@@ -218,6 +218,7 @@ typedef uint32_t krb5_enctype_set;
 
 typedef struct krb5_context_data {
     krb5_enctype *etypes;
+    krb5_enctype *cfg_etypes;
     krb5_enctype *etypes_des;/* deprecated */
     krb5_enctype *as_etypes;
     krb5_enctype *tgs_etypes;