add openssl_version_number & doc openssl_version_text (#3329)

* add openssl_version_number & doc openssl_version_text

fixes #3315

* more docs + actually assert on the test...

* text

3 files changed, 20 insertions, 0 deletions

diff --git a/docs/hazmat/backends/openssl.rst b/docs/hazmat/backends/openssl.rst
index e293c064..22807f1c 100644
--- a/docs/hazmat/backends/openssl.rst
+++ b/docs/hazmat/backends/openssl.rst
@@ -36,6 +36,20 @@ greater.
 
         The string name of this backend: ``"openssl"``
 
+    .. method:: openssl_version_text()
+
+        :return text: The friendly string name of the loaded OpenSSL library.
+            This is not necessarily the same version as it was compiled against.
+
+    .. method:: openssl_version_number()
+
+        .. versionadded:: 1.8
+
+        :return int: The integer version of the loaded OpenSSL library. This is
+            defined in ``opensslv.h`` as ``OPENSSL_VERSION_NUMBER`` and is
+            typically shown in hexadecimal (e.g. ``0x1010003f``). This is
+            not necessarily the same version as it was compiled against.
+
     .. method:: activate_osrandom_engine()
 
         Activates the OS random engine. This will effectively disable OpenSSL's
diff --git a/src/cryptography/hazmat/backends/openssl/backend.py b/src/cryptography/hazmat/backends/openssl/backend.py
index d2a9e6c9..a8d779ba 100644
--- a/src/cryptography/hazmat/backends/openssl/backend.py
+++ b/src/cryptography/hazmat/backends/openssl/backend.py
@@ -206,6 +206,9 @@ class Backend(object):
             self._lib.OpenSSL_version(self._lib.OPENSSL_VERSION)
         ).decode("ascii")
 
+    def openssl_version_number(self):
+        return self._lib.OpenSSL_version_num()
+
     def create_hmac_ctx(self, key, algorithm):
         return _HMACContext(self, key, algorithm)
 
diff --git a/tests/hazmat/backends/test_openssl.py b/tests/hazmat/backends/test_openssl.py
index 6d6f3452..8fa64bc8 100644
--- a/tests/hazmat/backends/test_openssl.py
+++ b/tests/hazmat/backends/test_openssl.py
@@ -71,6 +71,9 @@ class TestOpenSSL(object):
             backend.openssl_version_text().startswith("LibreSSL")
         )
 
+    def test_openssl_version_number(self):
+        assert backend.openssl_version_number() > 0
+
     def test_supports_cipher(self):
         assert backend.cipher_supported(None, None) is False