move salt_length from MGF1 to PSS and start deprecation cycle

1 files changed, 99 insertions, 41 deletions

diff --git a/tests/hazmat/primitives/test_rsa.py b/tests/hazmat/primitives/test_rsa.py
index c458a662..c159ab8b 100644
--- a/tests/hazmat/primitives/test_rsa.py
+++ b/tests/hazmat/primitives/test_rsa.py
@@ -454,10 +454,8 @@ class TestRSASignature(object):
         )
         signer = private_key.signer(
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=padding.MGF1.MAX_LENGTH
-                )
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
             ),
             hashes.SHA1(),
             backend
@@ -471,6 +469,23 @@ class TestRSASignature(object):
         verifier = public_key.verifier(
             signature,
             padding.PSS(
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
+            ),
+            hashes.SHA1(),
+            backend
+        )
+        verifier.update(binascii.unhexlify(example["message"]))
+        verifier.verify()
+
+    def test_deprecated_pss_mgf1_salt_length(self, backend):
+        private_key = rsa.RSAPrivateKey.generate(
+            public_exponent=65537,
+            key_size=512,
+            backend=backend
+        )
+        signer = private_key.signer(
+            padding.PSS(
                 mgf=padding.MGF1(
                     algorithm=hashes.SHA1(),
                     salt_length=padding.MGF1.MAX_LENGTH
@@ -479,7 +494,21 @@ class TestRSASignature(object):
             hashes.SHA1(),
             backend
         )
-        verifier.update(binascii.unhexlify(example["message"]))
+        signer.update(b"so deprecated")
+        signature = signer.finalize()
+        assert len(signature) == math.ceil(private_key.key_size / 8.0)
+        verifier = private_key.public_key().verifier(
+            signature,
+            padding.PSS(
+                mgf=padding.MGF1(
+                    algorithm=hashes.SHA1(),
+                    salt_length=padding.MGF1.MAX_LENGTH
+                )
+            ),
+            hashes.SHA1(),
+            backend
+        )
+        verifier.update(b"so deprecated")
         verifier.verify()
 
     @pytest.mark.parametrize(
@@ -498,10 +527,8 @@ class TestRSASignature(object):
         )
         public_key = private_key.public_key()
         pss = padding.PSS(
-            mgf=padding.MGF1(
-                algorithm=hash_alg,
-                salt_length=padding.MGF1.MAX_LENGTH
-            )
+            mgf=padding.MGF1(hash_alg),
+            salt_length=padding.PSS.MAX_LENGTH
         )
         signer = private_key.signer(
             pss,
@@ -531,10 +558,8 @@ class TestRSASignature(object):
         )
         signer = private_key.signer(
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=padding.MGF1.MAX_LENGTH
-                )
+                mgf=padding.MGF1(hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
             ),
             hashes.SHA512(),
             backend
@@ -555,10 +580,8 @@ class TestRSASignature(object):
         with pytest.raises(ValueError):
             private_key.signer(
                 padding.PSS(
-                    mgf=padding.MGF1(
-                        algorithm=hashes.SHA1(),
-                        salt_length=padding.MGF1.MAX_LENGTH
-                    )
+                    mgf=padding.MGF1(hashes.SHA1()),
+                    salt_length=padding.PSS.MAX_LENGTH
                 ),
                 hashes.SHA512(),
                 backend
@@ -572,10 +595,8 @@ class TestRSASignature(object):
         )
         signer = private_key.signer(
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=1000000
-                )
+                mgf=padding.MGF1(hashes.SHA1()),
+                salt_length=1000000
             ),
             hashes.SHA1(),
             backend
@@ -722,10 +743,8 @@ class TestRSAVerification(object):
         verifier = public_key.verifier(
             binascii.unhexlify(example["signature"]),
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=20
-                )
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=20
             ),
             hashes.SHA1(),
             backend
@@ -749,10 +768,8 @@ class TestRSAVerification(object):
         verifier = public_key.verifier(
             signature,
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=padding.MGF1.MAX_LENGTH
-                )
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
             ),
             hashes.SHA1(),
             backend
@@ -779,10 +796,8 @@ class TestRSAVerification(object):
         verifier = public_key.verifier(
             signature,
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=padding.MGF1.MAX_LENGTH
-                )
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
             ),
             hashes.SHA1(),
             backend
@@ -809,10 +824,8 @@ class TestRSAVerification(object):
         verifier = public_key.verifier(
             signature,
             padding.PSS(
-                mgf=padding.MGF1(
-                    algorithm=hashes.SHA1(),
-                    salt_length=padding.MGF1.MAX_LENGTH
-                )
+                mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                salt_length=padding.PSS.MAX_LENGTH
             ),
             hashes.SHA1(),
             backend
@@ -904,10 +917,8 @@ class TestRSAVerification(object):
             public_key.verifier(
                 signature,
                 padding.PSS(
-                    mgf=padding.MGF1(
-                        algorithm=hashes.SHA1(),
-                        salt_length=padding.MGF1.MAX_LENGTH
-                    )
+                    mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                    salt_length=padding.PSS.MAX_LENGTH
                 ),
                 hashes.SHA512(),
                 backend
@@ -1113,7 +1124,54 @@ class TestRSAPKCS1Verification(object):
     ))
 
 
+class TestPSS(object):
+    def test_deprecation_warning(self):
+        pytest.deprecated_call(
+            padding.PSS,
+            **{"mgf": padding.MGF1(hashes.SHA1(), 20)}
+        )
+
+    def test_invalid_salt_length_not_integer(self):
+        with pytest.raises(TypeError):
+            padding.PSS(
+                mgf=padding.MGF1(
+                    hashes.SHA1()
+                ),
+                salt_length=b"not_a_length"
+            )
+
+    def test_invalid_salt_length_negative_integer(self):
+        with pytest.raises(ValueError):
+            padding.PSS(
+                mgf=padding.MGF1(
+                    hashes.SHA1()
+                ),
+                salt_length=-1
+            )
+
+    def test_valid_pss_parameters(self):
+        algorithm = hashes.SHA1()
+        salt_length = algorithm.digest_size
+        mgf = padding.MGF1(algorithm)
+        pss = padding.PSS(mgf=mgf, salt_length=salt_length)
+        assert pss._mgf == mgf
+        assert pss._salt_length == salt_length
+
+    def test_valid_pss_parameters_maximum(self):
+        algorithm = hashes.SHA1()
+        mgf = padding.MGF1(algorithm)
+        pss = padding.PSS(mgf=mgf, salt_length=padding.PSS.MAX_LENGTH)
+        assert pss._mgf == mgf
+        assert pss._salt_length == padding.PSS.MAX_LENGTH
+
+
 class TestMGF1(object):
+    def test_deprecation_warning(self):
+        pytest.deprecated_call(
+            padding.MGF1,
+            **{"algorithm": hashes.SHA1(), "salt_length": 20}
+        )
+
     def test_invalid_hash_algorithm(self):
         with pytest.raises(TypeError):
             padding.MGF1(b"not_a_hash", 0)