Merge pull request #775 from reaperhulk/rsa-mgf1-class

add MGF1 class, docs, tests

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/hazmat/primitives/test_rsa.py b/tests/hazmat/primitives/test_rsa.py
index 79323265..114dc415 100644
--- a/tests/hazmat/primitives/test_rsa.py
+++ b/tests/hazmat/primitives/test_rsa.py
@@ -558,3 +558,30 @@ class TestRSAVerification(object):
         public_key = private_key.public_key()
         with pytest.raises(TypeError):
             public_key.verifier(b"sig", "notpadding", hashes.SHA1(), backend)
+
+
+class TestMGF1(object):
+    def test_invalid_hash_algorithm(self):
+        with pytest.raises(TypeError):
+            padding.MGF1(b"not_a_hash", 0)
+
+    def test_invalid_salt_length_not_integer(self):
+        with pytest.raises(TypeError):
+            padding.MGF1(hashes.SHA1(), b"not_a_length")
+
+    def test_invalid_salt_length_negative_integer(self):
+        with pytest.raises(ValueError):
+            padding.MGF1(hashes.SHA1(), -1)
+
+    def test_valid_mgf1_parameters(self):
+        algorithm = hashes.SHA1()
+        salt_length = algorithm.digest_size
+        mgf = padding.MGF1(algorithm, salt_length)
+        assert mgf._algorithm == algorithm
+        assert mgf._salt_length == salt_length
+
+    def test_valid_mgf1_parameters_maximum(self):
+        algorithm = hashes.SHA1()
+        mgf = padding.MGF1(algorithm, padding.MGF1.MAX_LENGTH)
+        assert mgf._algorithm == algorithm
+        assert mgf._salt_length == padding.MGF1.MAX_LENGTH