1 files changed, 8 insertions, 1 deletions

diff --git a/src/lib/libcrypto/dh/dh.h b/src/lib/libcrypto/dh/dh.h
index 0aff7fe21f..8562d16fb7 100644
--- a/src/lib/libcrypto/dh/dh.h
+++ b/src/lib/libcrypto/dh/dh.h
@@ -70,7 +70,14 @@
 #include <openssl/crypto.h>
 #include <openssl/ossl_typ.h>
         
-#define DH_FLAG_CACHE_MONT_P    0x01
+#define DH_FLAG_CACHE_MONT_P     0x01
+#define DH_FLAG_NO_EXP_CONSTTIME 0x02 /* new with 0.9.7h; the built-in DH
+                                       * implementation now uses constant time
+                                       * modular exponentiation for secret exponents
+                                       * by default. This flag causes the
+                                       * faster variable sliding window method to
+                                       * be used for all exponents.
+                                       */
 
 #ifdef  __cplusplus
 extern "C" {