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-rw-r--r--libtommath/bn_mp_and.c53
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diff --git a/libtommath/bn_mp_and.c b/libtommath/bn_mp_and.c
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+#include <tommath.h>
+#ifdef BN_MP_AND_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis
+ *
+ * LibTomMath is a library that provides multiple-precision
+ * integer arithmetic as well as number theoretic functionality.
+ *
+ * The library was designed directly after the MPI library by
+ * Michael Fromberger but has been written from scratch with
+ * additional optimizations in place.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@iahu.ca, http://math.libtomcrypt.org
+ */
+
+/* AND two ints together */
+int
+mp_and (mp_int * a, mp_int * b, mp_int * c)
+{
+ int res, ix, px;
+ mp_int t, *x;
+
+ if (a->used > b->used) {
+ if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
+ return res;
+ }
+ px = b->used;
+ x = b;
+ } else {
+ if ((res = mp_init_copy (&t, b)) != MP_OKAY) {
+ return res;
+ }
+ px = a->used;
+ x = a;
+ }
+
+ for (ix = 0; ix < px; ix++) {
+ t.dp[ix] &= x->dp[ix];
+ }
+
+ /* zero digits above the last from the smallest mp_int */
+ for (; ix < t.used; ix++) {
+ t.dp[ix] = 0;
+ }
+
+ mp_clamp (&t);
+ mp_exch (c, &t);
+ mp_clear (&t);
+ return MP_OKAY;
+}
+#endif