move urandom engine test

This test was in the bindings dir, which is incorrect. We do not set
the urandom engine to default unless the openssl backend is loaded. The
reason the test wasn't failing (even in the random test case) is that
the backends are loaded during pytest_generate_tests by a call to
_available_backends. So no matter what order it occurred in the engine
was already set to default. I discovered this when I tried to run the
test_openssl.py bindings tests directly via pytest. Hooray global state.

2 files changed, 27 insertions, 30 deletions

diff --git a/tests/hazmat/backends/test_openssl.py b/tests/hazmat/backends/test_openssl.py
index 6a2e8a77..a8401b30 100644
--- a/tests/hazmat/backends/test_openssl.py
+++ b/tests/hazmat/backends/test_openssl.py
@@ -34,6 +34,20 @@ from ..primitives.test_ec import _skip_curve_unsupported
 from ...utils import load_vectors_from_file, raises_unsupported_algorithm
 
 
+def skip_if_libre_ssl(openssl_version):
+    if b'LibreSSL' in openssl_version:
+        pytest.skip("LibreSSL hard-codes RAND_bytes to use arc4random.")
+
+
+class TestLibreSkip(object):
+    def test_skip_no(self):
+        assert skip_if_libre_ssl(b"OpenSSL 0.9.8zf 19 Mar 2015") is None
+
+    def test_skip_yes(self):
+        with pytest.raises(pytest.skip.Exception):
+            skip_if_libre_ssl(b"LibreSSL 2.1.6")
+
+
 @utils.register_interface(Mode)
 class DummyMode(object):
     name = "dummy-mode"
@@ -216,6 +230,19 @@ class TestOpenSSL(object):
         bn = backend._int_to_bn(0)
         assert backend._bn_to_int(bn) == 0
 
+    def test_actual_osrandom_bytes(self, monkeypatch):
+        skip_if_libre_ssl(backend.openssl_version_text())
+        sample_data = (b"\x01\x02\x03\x04" * 4)
+        length = len(sample_data)
+
+        def notrandom(size):
+            assert size == length
+            return sample_data
+        monkeypatch.setattr(os, "urandom", notrandom)
+        buf = backend._ffi.new("char[]", length)
+        backend._lib.RAND_bytes(buf, length)
+        assert backend._ffi.buffer(buf)[0:length] == sample_data
+
 
 class TestOpenSSLRandomEngine(object):
     def teardown_method(self, method):
diff --git a/tests/hazmat/bindings/test_openssl.py b/tests/hazmat/bindings/test_openssl.py
index f3f2eaf4..75a8e3f1 100644
--- a/tests/hazmat/bindings/test_openssl.py
+++ b/tests/hazmat/bindings/test_openssl.py
@@ -4,27 +4,11 @@
 
 from __future__ import absolute_import, division, print_function
 
-import os
-
 import pytest
 
 from cryptography.hazmat.bindings.openssl.binding import Binding
 
 
-def skip_if_libre_ssl(openssl_version):
-    if b'LibreSSL' in openssl_version:
-        pytest.skip("LibreSSL hard-codes RAND_bytes to use arc4random.")
-
-
-class TestLibreSkip(object):
-    def test_skip_no(self):
-        assert skip_if_libre_ssl(b"OpenSSL 0.9.8zf 19 Mar 2015") is None
-
-    def test_skip_yes(self):
-        with pytest.raises(pytest.skip.Exception):
-            skip_if_libre_ssl(b"LibreSSL 2.1.6")
-
-
 class TestOpenSSL(object):
     def test_binding_loads(self):
         binding = Binding()
@@ -108,20 +92,6 @@ class TestOpenSSL(object):
         with pytest.raises(RuntimeError):
             b._register_osrandom_engine()
 
-    def test_actual_osrandom_bytes(self, monkeypatch):
-        b = Binding()
-        skip_if_libre_ssl(b.ffi.string(b.lib.OPENSSL_VERSION_TEXT))
-        sample_data = (b"\x01\x02\x03\x04" * 4)
-        length = len(sample_data)
-
-        def notrandom(size):
-            assert size == length
-            return sample_data
-        monkeypatch.setattr(os, "urandom", notrandom)
-        buf = b.ffi.new("char[]", length)
-        b.lib.RAND_bytes(buf, length)
-        assert b.ffi.buffer(buf)[0:length] == sample_data
-
     def test_ssl_ctx_options(self):
         # Test that we're properly handling 32-bit unsigned on all platforms.
         b = Binding()