diff options
Diffstat (limited to 'src/crypto/x25519.c')
| -rw-r--r-- | src/crypto/x25519.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/src/crypto/x25519.c b/src/crypto/x25519.c index 19f9a2c02..ab5d2e8b0 100644 --- a/src/crypto/x25519.c +++ b/src/crypto/x25519.c @@ -564,6 +564,7 @@ void x25519_invert ( const union x25519_oct258 *invertend, */ static void x25519_reduce_by ( const x25519_t *subtrahend, x25519_t *value ) { x25519_t tmp; + int underflow; /* Conditionally subtract subtrahend * @@ -571,8 +572,8 @@ static void x25519_reduce_by ( const x25519_t *subtrahend, x25519_t *value ) { * time) if the subtraction underflows. */ bigint_copy ( value, &tmp ); - bigint_subtract ( subtrahend, value ); - bigint_swap ( value, &tmp, bigint_msb_is_set ( value ) ); + underflow = bigint_subtract ( subtrahend, value ); + bigint_swap ( value, &tmp, underflow ); } /** |