diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1d00d5c..410f059 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -225,6 +225,9 @@ if(WITH_GCRYPT AND LIBGCRYPT_LIBRARIES)
   set(ADDITIONAL_LIBS ${ADDITIONAL_LIBS} ${LIBGCRYPT_LIBRARIES})
 endif(WITH_GCRYPT AND LIBGCRYPT_LIBRARIES)
 
+if(OPENSSL_FOUND)
+  set(LIBVNCSERVER_HAVE_LIBSSL 1)
+endif(OPENSSL_FOUND)
 
 if(WITH_IPv6)
   if(WIN32 AND LIBVNCSERVER_HAVE_WS2TCPIP_H AND LIBVNCSERVER_HAVE_VPRINTF)
diff --git a/rfb/rfbconfig.h.cmake b/rfb/rfbconfig.h.cmake
index 661583d..58c9205 100644
--- a/rfb/rfbconfig.h.cmake
+++ b/rfb/rfbconfig.h.cmake
@@ -100,6 +100,9 @@
 /* Define to 1 if GnuTLS is present */
 #cmakedefine LIBVNCSERVER_WITH_CLIENT_TLS 1
 
+/* Define to 1 if OpenSSL is present */
+#cmakedefine LIBVNCSERVER_HAVE_LIBSSL 1
+
 /* Define to 1 to build with websockets */
 #cmakedefine LIBVNCSERVER_WITH_WEBSOCKETS 1