Implement support for GSSAPI extension RFC 5587

Signed-off-by: Alexander Scheel <ascheel@redhat.com>

gssapi/raw/__init__.py

@@ -69,6 +69,12 @@
 except ImportError:
     pass
 
+# optional RFC 5587 support
+try:
+    from gssapi.raw.ext_rfc5587 import *  # noqa
+except ImportError:
+    pass
+
 # optional RFC 5588 support
 try:
     from gssapi.raw.ext_rfc5588 import *  # noqa

gssapi/raw/ext_rfc5587.pyx

@@ -0,0 +1,103 @@
+from gssapi.raw.cython_types cimport *
+from gssapi.raw.oids cimport OID
+from gssapi.raw.cython_converters cimport c_create_oid_set
+GSSAPI="BASE"  # This ensures that a full module is generated by Cython
+
+from gssapi.raw.cython_converters cimport c_get_mech_oid_set
+
+from gssapi.raw.named_tuples import InquireAttrsResult, DisplayAttrResult
+from gssapi.raw.misc import GSSError
+
+cdef extern from "python_gssapi_ext.h":
+    OM_uint32 gss_indicate_mechs_by_attrs(
+        OM_uint32 *minor_status,
+        const gss_OID_set desired_mech_attrs,
+        const gss_OID_set except_mech_attrs,
+        const gss_OID_set critical_mech_attrs,
+        gss_OID_set *mechs)
+
+    OM_uint32 gss_inquire_attrs_for_mech(
+        OM_uint32 *minor_status,
+        const gss_OID mech,
+        gss_OID_set *mech_attrs,
+        gss_OID_set *known_mech_attrs)
+
+    OM_uint32 gss_display_mech_attr(
+        OM_uint32 *minor_status,
+        const gss_OID mech_attr,
+        gss_buffer_t name,
+        gss_buffer_t short_desc,
+        gss_buffer_t long_desc)
+
+
+def indicate_mechs_by_attrs(desired_mech_attrs=None, except_mech_attrs=None,
+                            critical_mech_attrs=None):
+    cdef OM_uint32 maj_stat, min_stat
+    cdef gss_OID_set desired_attrs = GSS_C_NO_OID_SET
+    cdef gss_OID_set except_attrs = GSS_C_NO_OID_SET
+    cdef gss_OID_set critical_attrs = GSS_C_NO_OID_SET
+    cdef gss_OID_set mechs
+
+    if desired_mech_attrs is not None:
+        desired_attrs = c_get_mech_oid_set(desired_mech_attrs)
+
+    if except_mech_attrs is not None:
+        except_attrs = c_get_mech_oid_set(except_mech_attrs)
+
+    if critical_mech_attrs is not None:
+        critical_attrs = c_get_mech_oid_set(critical_mech_attrs)
+
+    maj_stat = gss_indicate_mechs_by_attrs(&min_stat, desired_attrs,
+                                           except_attrs, critical_attrs,
+                                           &mechs)
+
+    if maj_stat == GSS_S_COMPLETE:
+        return c_create_oid_set(mechs)
+    else:
+        raise GSSError(maj_stat, min_stat)
+
+
+def inquire_attrs_for_mech(OID mech):
+    cdef OM_uint32 maj_stat, min_stat
+    cdef gss_OID m = GSS_C_NO_OID
+    cdef gss_OID_set mech_attrs = GSS_C_NO_OID_SET
+    cdef gss_OID_set known_mech_attrs = GSS_C_NO_OID_SET
+
+    if mech is not None:
+        m = &mech.raw_oid
+
+    maj_stat = gss_inquire_attrs_for_mech(&min_stat, m, &mech_attrs,
+                                          &known_mech_attrs)
+
+    if maj_stat == GSS_S_COMPLETE:
+        return InquireAttrsResult(c_create_oid_set(mech_attrs),
+                                  c_create_oid_set(known_mech_attrs))
+    else:
+        raise GSSError(maj_stat, min_stat)
+
+
+def display_mech_attr(OID attr):
+    cdef OM_uint32 maj_stat, min_stat
+    cdef gss_OID a = GSS_C_NO_OID
+    cdef gss_buffer_desc name
+    cdef gss_buffer_desc short_desc
+    cdef gss_buffer_desc long_desc
+
+    if attr is not None:
+        a = &attr.raw_oid
+
+    maj_stat = gss_display_mech_attr(&min_stat, a, &name, &short_desc,
+                                     &long_desc)
+
+    if maj_stat == GSS_S_COMPLETE:
+        out_name = name.value[:name.length].decode("UTF-8")
+        out_short = short_desc.value[:short_desc.length].decode("UTF-8")
+        out_long = long_desc.value[:long_desc.length].decode("UTF-8")
+
+        gss_release_buffer(&min_stat, &name)
+        gss_release_buffer(&min_stat, &short_desc)
+        gss_release_buffer(&min_stat, &long_desc)
+
+        return DisplayAttrResult(out_name, out_short, out_long)
+    else:
+        raise GSSError(maj_stat, min_stat)

gssapi/raw/named_tuples.py

@@ -64,3 +64,9 @@
 GetNameAttributeResult = namedtuple('GetNamedAttributeResult',
                                     ['values', 'display_values',
                                      'authenticated', 'complete'])
+
+InquireAttrsResult = namedtuple('InquireAttrsResult',
+                                ['mech_attrs', 'known_mech_attrs'])
+
+DisplayAttrResult = namedtuple('DisplayAttrResult', ['name', 'short_desc',
+                                                     'long_desc'])

gssapi/tests/test_raw.py

@@ -644,6 +644,72 @@ def test_add_cred_with_password(self):
 
         new_creds.should_be_a(gb.Creds)
 
+    @ktu.gssapi_extension_test('rfc5587', 'RFC 5587')
+    def test_rfc5587(self):
+        mechs = gb.indicate_mechs_by_attrs(None, None, None)
+        mechs.shouldnt_be_empty()
+        mechs.should_be_a(set)
+
+        last_mech = None
+        last_attr = None
+
+        for mech in mechs:
+            mech.shouldnt_be_none
+            mech.should_be_a(gb.OID)
+
+            inquire_out = gb.inquire_attrs_for_mech(mech)
+            mech_attrs = inquire_out.mech_attrs
+            known_mech_attrs = inquire_out.known_mech_attrs
+
+            mech_attrs.shouldnt_be_empty
+            known_mech_attrs.shouldnt_be_empty
+            mech_attrs.should_be_a(set)
+            known_mech_attrs.should_be_a(set)
+
+            for mech_attr in mech_attrs:
+                mech_attr.shouldnt_be_none
+                mech_attr.should_be_a(gb.OID)
+
+                display_out = gb.display_mech_attr(mech_attr)
+                display_out.name.shouldnt_be_none
+                display_out.name.should_be_a(str)
+                display_out.long_desc.shouldnt_be_none
+                display_out.long_desc.should_be_a(str)
+                display_out.short_desc.shouldnt_be_none
+                display_out.short_desc.should_be_a(str)
+
+                last_attr = mech_attr
+
+            for mech_attr in known_mech_attrs:
+                mech_attr.shouldnt_be_none
+                mech_attr.should_be_a(gb.OID)
+
+                display_out = gb.display_mech_attr(mech_attr)
+                display_out.name.shouldnt_be_none
+                display_out.name.should_be_a(str)
+                display_out.long_desc.shouldnt_be_none
+                display_out.long_desc.should_be_a(str)
+                display_out.short_desc.shouldnt_be_none
+                display_out.short_desc.should_be_a(str)
+
+            last_mech = mech
+
+        last_mech.shouldnt_be_none
+        last_attr.shouldnt_be_none
+
+        attrs = set([last_attr])
+
+        mechs = gb.indicate_mechs_by_attrs(attrs, None, None)
+        mechs.shouldnt_be_empty()
+        mechs.should_include(last_mech)
+
+        mechs = gb.indicate_mechs_by_attrs(None, attrs, None)
+        mechs.shouldnt_include(last_mech)
+
+        mechs = gb.indicate_mechs_by_attrs(None, None, attrs)
+        mechs.shouldnt_be_empty()
+        mechs.should_include(last_mech)
+
 
 class TestIntEnumFlagSet(unittest.TestCase):
     def test_create_from_int(self):

setup.py

@@ -253,6 +253,7 @@ def gssapi_modules(lst):
         main_file('chan_bindings'),
         extension_file('s4u', 'gss_acquire_cred_impersonate_name'),
         extension_file('cred_store', 'gss_store_cred_into'),
+        extension_file('rfc5587', 'gss_indicate_mechs_by_attrs'),
         extension_file('rfc5588', 'gss_store_cred'),
         extension_file('cred_imp_exp', 'gss_import_cred'),
         extension_file('dce', 'gss_wrap_iov'),