commit cbdc9baafd4cc919abc7aed070d08d8ea847aa33
author Thierry Bastian <thierryb@filewave.com> Thu Apr 05 16:15:53 2018 +0200
committer Paul Kehrer <paul.l.kehrer@gmail.com> Thu Apr 05 09:15:53 2018 -0500
tree 956d37647925f000718ad5b6cab4aa7205ba0597
parent d57c79e0434ee224c00bcfd5b28e958144a1722b

OpenSSL 1.0.2o has switched to winsock2 (#4184)

So here we need to make sure we don't simply include windows but only the parts that we want

src/_cffi_src/openssl/callbacks.py

diff --git a/src/_cffi_src/openssl/callbacks.py b/src/_cffi_src/openssl/callbacks.py
index cf2b2da..e215ed4 100644
--- a/src/_cffi_src/openssl/callbacks.py
+++ b/src/_cffi_src/openssl/callbacks.py
@@ -11,7 +11,10 @@
 #include <openssl/crypto.h>
 
 #ifdef _WIN32
+#define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
+#include <Wincrypt.h>
+#include <Winsock2.h>
 #else
 #include <stdio.h>
 #include <stdlib.h>

src/_cffi_src/openssl/cryptography.py

diff --git a/src/_cffi_src/openssl/cryptography.py b/src/_cffi_src/openssl/cryptography.py
index 9095e3a..4f9378d 100644
--- a/src/_cffi_src/openssl/cryptography.py
+++ b/src/_cffi_src/openssl/cryptography.py
@@ -22,7 +22,10 @@
 #include <openssl/e_os2.h>
 #endif
 #if defined(_WIN32)
+#define WIN32_LEAN_AND_MEAN
 #include <windows.h>
+#include <Wincrypt.h>
+#include <Winsock2.h>
 #endif
 
 #define CRYPTOGRAPHY_OPENSSL_102_OR_GREATER \