diff --git a/src/numtheory/fp_prime_random_ex.c b/src/numtheory/fp_prime_random_ex.c index 05fb49a..106d216 100644 --- a/src/numtheory/fp_prime_random_ex.c +++ b/src/numtheory/fp_prime_random_ex.c @@ -35,7 +35,7 @@ int fp_prime_random_ex(fp_int *a, int t, int size, int flags, tfm_prime_callback } /* calc the maskAND value for the MSbyte*/ - maskAND = 0xFF >> (8 - (size & 7)); + maskAND = 0xFF >> ((8 - (size & 7)) & 7); /* calc the maskOR_msb */ maskOR_msb = 0;