From 3181dfa7abfe7b623d8823e078f04a374775e978 Mon Sep 17 00:00:00 2001 From: Jack Lloyd Date: Thu, 15 Oct 2015 10:07:36 -0400 Subject: Periodically reinitialize the blinding sequence instead of always deriving it by squaring the previous value. --- src/build-data/buildh.in | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'src/build-data') diff --git a/src/build-data/buildh.in b/src/build-data/buildh.in index eaf4181b5..31069f0ae 100644 --- a/src/build-data/buildh.in +++ b/src/build-data/buildh.in @@ -71,9 +71,20 @@ * representation of an ECC point. Set to zero to diable this * side-channel countermeasure. */ -#define BOTAN_POINTGFP_RANDOMIZE_BLINDING_BITS 64 +#define BOTAN_POINTGFP_RANDOMIZE_BLINDING_BITS 80 -#define BOTAN_CURVE_GFP_USE_MONTGOMERY_LADDER 0 +/* +* Normally blinding is performed by choosing a random starting point (plus +* its inverse, of a form appropriate to the algorithm being blinded), and +* then choosing new blinding operands by successive squaring of both +* values. This is much faster than computing a new starting point but +* introduces some possible coorelation +* +* To avoid possible leakage problems in long-running processes, the blinder +* periodically reinitializes the sequence. This value specifies how often +* a new sequence should be started. +*/ +#define BOTAN_BLINDING_REINIT_INTERVAL 32 /* PK key consistency checking toggles */ #define BOTAN_PUBLIC_KEY_STRONG_CHECKS_ON_LOAD 1 -- cgit v1.2.3