1 files changed, 11 insertions, 2 deletions
diff --git a/libtommath/bn_mp_radix_size.c b/libtommath/bn_mp_radix_size.c
index 3d423ba..29b1d22 100644
--- a/libtommath/bn_mp_radix_size.c
+++ b/libtommath/bn_mp_radix_size.c
@@ -66,8 +66,17 @@ int mp_radix_size (mp_int * a, int radix, int *size)
   }
   mp_clear (&t);
 
-  /* return digs + 1, the 1 is for the NULL byte that would be required. */
-  *size = digs + 1;
+  /* 
+   * return digs + 1, the 1 is for the NULL byte that would be required.
+   * mp_toradix_n requires a minimum of 3 bytes, so never report less than
+   * that.
+   */
+
+  if ( digs >= 2 ) {
+      *size = digs + 1;
+  } else {
+      *size = 3;
+  }
   return MP_OKAY;
 }