commit 29c3008aa12d845850aae6d8f52aee6d3609dda0
author Paul Kehrer <paul.l.kehrer@gmail.com> Thu May 01 15:47:24 2014 -0500
committer Paul Kehrer <paul.l.kehrer@gmail.com> Fri May 02 08:48:29 2014 -0500
tree 64e7899946d829f10ff70431ece9ebb66b18ae8c
parent d80ff2d3a6a443e5aea217d6bc3d356dab2b99b4

expand DSA multibackend support

cryptography/hazmat/backends/multibackend.py

diff --git a/cryptography/hazmat/backends/multibackend.py b/cryptography/hazmat/backends/multibackend.py
index 981a60b..753f4fc 100644
--- a/cryptography/hazmat/backends/multibackend.py
+++ b/cryptography/hazmat/backends/multibackend.py
@@ -158,6 +158,31 @@
         raise UnsupportedAlgorithm("DSA is not supported by the backend",
                                    _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
 
+    def create_dsa_verification_ctx(self, public_key, signature, algorithm):
+        for b in self._filtered_backends(DSABackend):
+            return b.create_dsa_verification_ctx(public_key, signature,
+                                                 algorithm)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def create_dsa_signature_ctx(self, private_key, algorithm):
+        for b in self._filtered_backends(DSABackend):
+            return b.create_dsa_signature_ctx(private_key, algorithm)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def dsa_hash_supported(self, algorithm):
+        for b in self._filtered_backends(DSABackend):
+            return b.dsa_hash_supported(algorithm)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def dsa_parameters_supported(self, p, q, g):
+        for b in self._filtered_backends(DSABackend):
+            return b.dsa_parameters_supported(p, q, g)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
     def cmac_algorithm_supported(self, algorithm):
         return any(
             b.cmac_algorithm_supported(algorithm)

tests/hazmat/backends/test_multibackend.py

diff --git a/tests/hazmat/backends/test_multibackend.py b/tests/hazmat/backends/test_multibackend.py
index d8c09bd..c31b235 100644
--- a/tests/hazmat/backends/test_multibackend.py
+++ b/tests/hazmat/backends/test_multibackend.py
@@ -107,6 +107,18 @@
     def generate_dsa_private_key(self, parameters):
         pass
 
+    def create_dsa_signature_ctx(self, private_key, algorithm):
+        pass
+
+    def create_dsa_verification_ctx(self, public_key, signature, algorithm):
+        pass
+
+    def dsa_hash_supported(self, algorithm):
+        pass
+
+    def dsa_parameters_supported(self, p, q, g):
+        pass
+
 
 @utils.register_interface(CMACBackend)
 class DummyCMACBackend(object):
@@ -238,6 +250,28 @@
         ):
             backend.generate_dsa_private_key(parameters)
 
+        with raises_unsupported_algorithm(
+            _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
+        ):
+            backend.create_dsa_signature_ctx("private_key", hashes.SHA1())
+
+        with raises_unsupported_algorithm(
+            _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
+        ):
+            backend.create_dsa_verification_ctx(
+                "public_key", b"sig", hashes.SHA1()
+            )
+
+        with raises_unsupported_algorithm(
+            _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
+        ):
+            backend.dsa_hash_supported(hashes.SHA1())
+
+        with raises_unsupported_algorithm(
+            _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
+        ):
+            backend.dsa_parameters_supported('p', 'q', 'g')
+
     def test_cmac(self):
         backend = MultiBackend([
             DummyCMACBackend([algorithms.AES])