1 files changed, 52 insertions, 0 deletions
diff --git a/tests/hazmat/primitives/utils.py b/tests/hazmat/primitives/utils.py
index e148bc63..e45466d8 100644
--- a/tests/hazmat/primitives/utils.py
+++ b/tests/hazmat/primitives/utils.py
@@ -18,6 +18,9 @@ from cryptography.hazmat.primitives import hashes, hmac
 from cryptography.hazmat.primitives.asymmetric import rsa
 from cryptography.hazmat.primitives.ciphers import Cipher
 from cryptography.hazmat.primitives.kdf.hkdf import HKDF, HKDFExpand
+from cryptography.hazmat.primitives.kdf.kbkdf import (
+    CounterLocation, KBKDFHMAC, Mode
+)
 from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
 
 from ...utils import load_vectors_from_file
@@ -370,6 +373,55 @@ def generate_hkdf_test(param_loader, path, file_names, algorithm):
     return test_hkdf
 
 
+def generate_kbkdf_counter_mode_test(param_loader, path, file_names):
+    all_params = _load_all_params(path, file_names, param_loader)
+
+    @pytest.mark.parametrize("params", all_params)
+    def test_kbkdf(self, backend, params):
+        kbkdf_counter_mode_test(backend, params)
+    return test_kbkdf
+
+
+def kbkdf_counter_mode_test(backend, params):
+    supported_algorithms = {
+        'hmac_sha1': hashes.SHA1,
+        'hmac_sha224': hashes.SHA224,
+        'hmac_sha256': hashes.SHA256,
+        'hmac_sha384': hashes.SHA384,
+        'hmac_sha512': hashes.SHA512,
+    }
+
+    supportd_counter_locations = {
+        "before_fixed": CounterLocation.BeforeFixed,
+        "after_fixed": CounterLocation.AfterFixed,
+    }
+
+    algorithm = supported_algorithms.get(params.get('prf'))
+    if algorithm is None or not backend.hmac_supported(algorithm()):
+        pytest.skip('Does not support algorithm')
+
+    ctr_loc = supportd_counter_locations.get(params.get("ctrlocation"))
+    if ctr_loc is None or not isinstance(ctr_loc, CounterLocation):
+        pytest.skip("Does not support counter location".format(
+            location=params.get('ctrlocation')
+        ))
+
+    ctrkdf = KBKDFHMAC(
+        algorithm(),
+        Mode.CounterMode,
+        params['l'] // 8,
+        params['rlen'] // 8,
+        None,
+        ctr_loc,
+        None,
+        None,
+        binascii.unhexlify(params['fixedinputdata']),
+        backend=backend)
+
+    ko = ctrkdf.derive(binascii.unhexlify(params['ki']))
+    assert binascii.hexlify(ko) == params["ko"]
+
+
 def generate_rsa_verification_test(param_loader, path, file_names, hash_alg,
                                    pad_factory):
     all_params = _load_all_params(path, file_names, param_loader)