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-rw-r--r--libtommath/bn_mp_reduce_2k_l.c30
1 files changed, 18 insertions, 12 deletions
diff --git a/libtommath/bn_mp_reduce_2k_l.c b/libtommath/bn_mp_reduce_2k_l.c
index 8e52efa..3225214 100644
--- a/libtommath/bn_mp_reduce_2k_l.c
+++ b/libtommath/bn_mp_reduce_2k_l.c
@@ -1,4 +1,4 @@
-#include <tommath.h>
+#include <tommath_private.h>
#ifdef BN_MP_REDUCE_2K_L_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -12,10 +12,10 @@
* The library is free for all purposes without any express
* guarantee it works.
*
- * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
+ * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
*/
-/* reduces a modulo n where n is of the form 2**p - d
+/* reduces a modulo n where n is of the form 2**p - d
This differs from reduce_2k since "d" can be larger
than a single digit.
*/
@@ -23,36 +23,42 @@ int mp_reduce_2k_l(mp_int *a, mp_int *n, mp_int *d)
{
mp_int q;
int p, res;
-
+
if ((res = mp_init(&q)) != MP_OKAY) {
return res;
}
-
- p = mp_count_bits(n);
+
+ p = mp_count_bits(n);
top:
/* q = a/2**p, a = a mod 2**p */
if ((res = mp_div_2d(a, p, &q, a)) != MP_OKAY) {
goto ERR;
}
-
+
/* q = q * d */
- if ((res = mp_mul(&q, d, &q)) != MP_OKAY) {
+ if ((res = mp_mul(&q, d, &q)) != MP_OKAY) {
goto ERR;
}
-
+
/* a = a + q */
if ((res = s_mp_add(a, &q, a)) != MP_OKAY) {
goto ERR;
}
-
+
if (mp_cmp_mag(a, n) != MP_LT) {
- s_mp_sub(a, n, a);
+ if ((res = s_mp_sub(a, n, a)) != MP_OKAY) {
+ goto ERR;
+ }
goto top;
}
-
+
ERR:
mp_clear(&q);
return res;
}
#endif
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */