1 files changed, 29 insertions, 0 deletions
diff --git a/libtommath/bn_mp_to_signed_bin.c b/libtommath/bn_mp_to_signed_bin.c
new file mode 100644
index 0000000..7871921
--- /dev/null
+++ b/libtommath/bn_mp_to_signed_bin.c
@@ -0,0 +1,29 @@
+#include <tommath.h>
+#ifdef BN_MP_TO_SIGNED_BIN_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@gmail.com, http://math.libtomcrypt.com
+ */
+
+/* store in signed [big endian] format */
+int mp_to_signed_bin (mp_int * a, unsigned char *b)
+{
+  int     res;
+
+  if ((res = mp_to_unsigned_bin (a, b + 1)) != MP_OKAY) {
+    return res;
+  }
+  b[0] = (unsigned char) ((a->sign == MP_ZPOS) ? 0 : 1);
+  return MP_OKAY;
+}
+#endif