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            to branch 'au.asn.ucc.matt.dropbear' (head fff0894a0399405a9410ea1c6d118f342cf2aa64)

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extra : convert_revision : fdf4a7a3b97ae5046139915de7e40399cceb2c01

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diff --git a/libtommath/bn_mp_div_2.c b/libtommath/bn_mp_div_2.c
new file mode 100644
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--- /dev/null
+++ b/libtommath/bn_mp_div_2.c
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+#include <tommath.h>
+#ifdef BN_MP_DIV_2_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
+ */
+
+/* b = a/2 */
+int mp_div_2(mp_int * a, mp_int * b)
+{
+  int     x, res, oldused;
+
+  /* copy */
+  if (b->alloc < a->used) {
+    if ((res = mp_grow (b, a->used)) != MP_OKAY) {
+      return res;
+    }
+  }
+
+  oldused = b->used;
+  b->used = a->used;
+  {
+    register mp_digit r, rr, *tmpa, *tmpb;
+
+    /* source alias */
+    tmpa = a->dp + b->used - 1;
+
+    /* dest alias */
+    tmpb = b->dp + b->used - 1;
+
+    /* carry */
+    r = 0;
+    for (x = b->used - 1; x >= 0; x--) {
+      /* get the carry for the next iteration */
+      rr = *tmpa & 1;
+
+      /* shift the current digit, add in carry and store */
+      *tmpb-- = (*tmpa-- >> 1) | (r << (DIGIT_BIT - 1));
+
+      /* forward carry to next iteration */
+      r = rr;
+    }
+
+    /* zero excess digits */
+    tmpb = b->dp + b->used;
+    for (x = b->used; x < oldused; x++) {
+      *tmpb++ = 0;
+    }
+  }
+  b->sign = a->sign;
+  mp_clamp (b);
+  return MP_OKAY;
+}
+#endif