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-rw-r--r--libtommath/bn_mp_reduce_2k.c28
1 files changed, 17 insertions, 11 deletions
diff --git a/libtommath/bn_mp_reduce_2k.c b/libtommath/bn_mp_reduce_2k.c
index 428f2ff..2876a75 100644
--- a/libtommath/bn_mp_reduce_2k.c
+++ b/libtommath/bn_mp_reduce_2k.c
@@ -1,4 +1,4 @@
-#include <tommath.h>
+#include <tommath_private.h>
#ifdef BN_MP_REDUCE_2K_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -12,7 +12,7 @@
* 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 */
@@ -20,38 +20,44 @@ int mp_reduce_2k(mp_int *a, mp_int *n, mp_digit 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;
}
-
+
if (d != 1) {
/* q = q * d */
- if ((res = mp_mul_d(&q, d, &q)) != MP_OKAY) {
+ if ((res = mp_mul_d(&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
+
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */