X-Git-Url: https://www.bearssl.org/gitweb//home/git/?p=BearSSL;a=blobdiff_plain;f=src%2Fconfig.h;h=e7a440e968646cdf547ff85983d8ac90162ab78c;hp=259f5bbb162a33503ea2305095fc9b0da4b29c49;hb=28e4e120b84dacdf53963639f1a8a6fec2793662;hpb=3210f38e0491b39aec1ef419cb4114e9483089fb

diff --git a/src/config.h b/src/config.h
index 259f5bb..e7a440e 100644
--- a/src/config.h
+++ b/src/config.h
@@ -60,6 +60,25 @@
 #define BR_CT_MUL31   1
  */
 
+/*
+ * When BR_CT_MUL15 is enabled, multiplications of 15-bit values (held
+ * in 32-bit words) use an alternate implementation which is slower and
+ * larger than the normal multiplication, but should ensure
+ * constant-time multiplications on most/all architectures where the
+ * basic multiplication is not constant-time.
+#define BR_CT_MUL15   1
+ */
+
+/*
+ * When BR_NO_ARITH_SHIFT is enabled, arithmetic right shifts (with sign
+ * extension) are performed with a sequence of operations which is bigger
+ * and slower than a simple right shift on a signed value. This avoids
+ * relying on an implementation-defined behaviour. However, most if not
+ * all C compilers use sign extension for right shifts on signed values,
+ * so this alternate macro is disabled by default.
+#define BR_NO_ARITH_SHIFT   1
+ */
+
 /*
  * When BR_USE_URANDOM is enabled, the SSL engine will use /dev/urandom
  * to automatically obtain quality randomness for seedings its internal