diff libtommath/bn_mp_lshd.c @ 1655:f52919ffd3b1

update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) * make key-generation compliant to FIPS 186.4 * fix includes in tommath_class.h * update fuzzcorpus instead of error-out * fixup fuzzing make-targets * update Makefile.in * apply necessary patches to ltm sources * clean-up not required ltm files * update to vanilla ltm 1.1.0 this already only contains the required files * remove set/get double
author Steffen Jaeckel <s_jaeckel@gmx.de>
date Mon, 16 Sep 2019 15:50:38 +0200
parents 8bba51a55704
children 1051e4eea25a
line wrap: on
line diff
--- a/libtommath/bn_mp_lshd.c	Wed May 15 21:59:45 2019 +0800
+++ b/libtommath/bn_mp_lshd.c	Mon Sep 16 15:50:38 2019 +0200
@@ -1,4 +1,4 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
 #ifdef BN_MP_LSHD_C
 /* LibTomMath, multiple-precision integer library -- Tom St Denis
  *
@@ -9,59 +9,60 @@
  * 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, [email protected], http://libtom.org
+ * SPDX-License-Identifier: Unlicense
  */
 
 /* shift left a certain amount of digits */
-int mp_lshd (mp_int * a, int b)
+int mp_lshd(mp_int *a, int b)
 {
-  int     x, res;
-
-  /* if its less than zero return */
-  if (b <= 0) {
-    return MP_OKAY;
-  }
+   int     x, res;
 
-  /* grow to fit the new digits */
-  if (a->alloc < (a->used + b)) {
-     if ((res = mp_grow (a, a->used + b)) != MP_OKAY) {
-       return res;
-     }
-  }
+   /* if its less than zero return */
+   if (b <= 0) {
+      return MP_OKAY;
+   }
+   /* no need to shift 0 around */
+   if (mp_iszero(a) == MP_YES) {
+      return MP_OKAY;
+   }
 
-  {
-    mp_digit *top, *bottom;
+   /* grow to fit the new digits */
+   if (a->alloc < (a->used + b)) {
+      if ((res = mp_grow(a, a->used + b)) != MP_OKAY) {
+         return res;
+      }
+   }
 
-    /* increment the used by the shift amount then copy upwards */
-    a->used += b;
+   {
+      mp_digit *top, *bottom;
 
-    /* top */
-    top = a->dp + a->used - 1;
+      /* increment the used by the shift amount then copy upwards */
+      a->used += b;
 
-    /* base */
-    bottom = (a->dp + a->used - 1) - b;
+      /* top */
+      top = a->dp + a->used - 1;
+
+      /* base */
+      bottom = (a->dp + a->used - 1) - b;
 
-    /* much like mp_rshd this is implemented using a sliding window
-     * except the window goes the otherway around.  Copying from
-     * the bottom to the top.  see bn_mp_rshd.c for more info.
-     */
-    for (x = a->used - 1; x >= b; x--) {
-      *top-- = *bottom--;
-    }
+      /* much like mp_rshd this is implemented using a sliding window
+       * except the window goes the otherway around.  Copying from
+       * the bottom to the top.  see bn_mp_rshd.c for more info.
+       */
+      for (x = a->used - 1; x >= b; x--) {
+         *top-- = *bottom--;
+      }
 
-    /* zero the lower digits */
-    top = a->dp;
-    for (x = 0; x < b; x++) {
-      *top++ = 0;
-    }
-  }
-  return MP_OKAY;
+      /* zero the lower digits */
+      top = a->dp;
+      for (x = 0; x < b; x++) {
+         *top++ = 0;
+      }
+   }
+   return MP_OKAY;
 }
 #endif
 
-/* ref:         $Format:%D$ */
-/* git commit:  $Format:%H$ */
-/* commit time: $Format:%ai$ */
+/* ref:         HEAD -> master, tag: v1.1.0 */
+/* git commit:  08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
+/* commit time: 2019-01-28 20:32:32 +0100 */