From fbe4c947cd6254f3221f5fa8a442cad0da4e65bb Mon Sep 17 00:00:00 2001 From: Janos Follath Date: Mon, 28 Oct 2019 12:37:21 +0000 Subject: [PATCH] mbedtls_mpi_lt_mpi_ct: simplify condition In the case of *ret we might need to preserve a 0 value throughout the loop and therefore we need an extra condition to protect it from being overwritten. The value of done is always 1 after *ret has been set and does not need to be protected from overwriting. Therefore in this case the extra condition can be removed. --- library/bignum.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/library/bignum.c b/library/bignum.c index 7b18cf214..6a725976a 100644 --- a/library/bignum.c +++ b/library/bignum.c @@ -1155,7 +1155,7 @@ int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y, */ cond = ct_lt_mpi_uint( Y->p[i - 1], X->p[i - 1] ) & X_is_negative; *ret |= cond & ( 1 - done ); - done |= cond & ( 1 - done ); + done |= cond; /* * If X->p[i - 1] < Y->p[i - 1] and both X and Y are positive, then @@ -1167,7 +1167,7 @@ int mbedtls_mpi_lt_mpi_ct( const mbedtls_mpi *X, const mbedtls_mpi *Y, cond = ct_lt_mpi_uint( X->p[i - 1], Y->p[i - 1] ) & ( 1 - X_is_negative ); *ret |= cond & ( 1 - done ); - done |= cond & ( 1 - done ); + done |= cond; } return( 0 );