cmake: added Windows SSL support

Closes #399

CMakeLists.txt

@@ -122,10 +122,10 @@ endif()
 option(CURL_HIDDEN_SYMBOLS "Set to ON to hide libcurl internal symbols (=hide all symbols that aren't officially external)." ON)
 mark_as_advanced(CURL_HIDDEN_SYMBOLS)
 
-# IF(WIN32)
-# OPTION(CURL_WINDOWS_SSPI "Use windows libraries to allow NTLM authentication without openssl" ON)
-# MARK_AS_ADVANCED(CURL_WINDOWS_SSPI)
-# ENDIF()
+IF(WIN32)
+  OPTION(CURL_WINDOWS_SSPI "Use windows libraries to allow NTLM authentication without openssl" ON)
+  MARK_AS_ADVANCED(CURL_WINDOWS_SSPI)
+ENDIF()
 
 option(HTTP_ONLY "disables all protocols except HTTP (This overrides all CURL_DISABLE_* options)" OFF)
 mark_as_advanced(HTTP_ONLY)
@@ -558,6 +558,18 @@ if(NOT UNIX)
   check_include_file_concat("winsock.h"      HAVE_WINSOCK_H)
   check_include_file_concat("ws2tcpip.h"     HAVE_WS2TCPIP_H)
   check_include_file_concat("winsock2.h"     HAVE_WINSOCK2_H)
+  if(CURL_WINDOWS_SSPI)
+    set(CMAKE_REQUIRED_DEFINITIONS "${CMAKE_REQUIRED_DEFINITIONS} -DSECURITY_WIN32")
+    check_include_file_concat("sspi.h"       HAVE_SSPI_H)
+    if(HAVE_SSPI_H)
+      check_include_file_concat("schannel.h" HAVE_SCHANNEL_H)
+      set(USE_WINDOWS_SSPI ON)
+      if(HAVE_SCHANNEL_H)
+        set(USE_SCHANNEL ON)
+        set(SSL_ENABLED ON)
+      endif()
+    endif()
+  endif()
 endif(NOT UNIX)
 
 check_include_file_concat("stdio.h"          HAVE_STDIO_H)

lib/curl_config.h.cmake

@@ -919,6 +919,9 @@
 /* to enable SSPI support */
 #cmakedefine USE_WINDOWS_SSPI 1
 
+/* to enable Windows SSL  */
+#cmakedefine USE_SCHANNEL 1
+
 /* Define to 1 if using yaSSL in OpenSSL compatibility mode. */
 #cmakedefine USE_YASSLEMUL 1