From 2c8cfcf59f404a8dd84f75e45022507a1ceec800 Mon Sep 17 00:00:00 2001 From: Gilles Peskine Date: Sat, 3 Apr 2021 21:40:11 +0200 Subject: [PATCH] Fix an incorrect comment about fix_negative We're subtracting multiples of 2^bits, not 2^(bits+32). Signed-off-by: Gilles Peskine --- library/ecp_curves.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/library/ecp_curves.c b/library/ecp_curves.c index b04596b56..396734d17 100644 --- a/library/ecp_curves.c +++ b/library/ecp_curves.c @@ -1048,13 +1048,13 @@ static inline void sub32( uint32_t *dst, uint32_t src, signed char *carry ) /* * If the result is negative, we get it in the form - * c * 2^(bits + 32) + N, with c negative and N positive shorter than 'bits' + * c * 2^bits + N, with c negative and N positive shorter than 'bits' */ static inline int fix_negative( mbedtls_mpi *N, signed char c, mbedtls_mpi *C, size_t bits ) { int ret; - /* C = - c * 2^(bits + 32) */ + /* C = - c * 2^bits */ #if !defined(MBEDTLS_HAVE_INT64) ((void) bits); #else