From 5377b45d9743bf78b8cd75a6ce0dd5f0cae21213 Mon Sep 17 00:00:00 2001
From: Peter Conrad <conrad@quisquis.de>
Date: Thu, 30 Jul 2015 14:58:35 +0200
Subject: [PATCH] Fixed signedness, simplified word-shift

---
 src/crypto/_digest_common.cpp | 28 ++++++++++++----------------
 src/crypto/_digest_common.hpp |  2 +-
 2 files changed, 13 insertions(+), 17 deletions(-)

diff --git a/src/crypto/_digest_common.cpp b/src/crypto/_digest_common.cpp
index eeb1bc7..2c5c652 100644
--- a/src/crypto/_digest_common.cpp
+++ b/src/crypto/_digest_common.cpp
@@ -1,33 +1,29 @@
-#include <boost/endian/conversion.hpp>
 #include <fc/exception/exception.hpp>
 #include "_digest_common.hpp"
 
 namespace fc { namespace detail {
-    static void shift_l( const uint32_t* in, uint32_t* out, std::size_t n, int i) {
+    static void shift_l( const uint8_t* in, uint8_t* out, std::size_t n, unsigned int i) {
         if (i < n) {
-            memcpy( out, in + i, 4*(n-i) );
+            memcpy( out, in + i, n-i );
         } else {
             i = n;
         }
-        memset( out + (n-i), 0, 4 * i );
+        memset( out + (n-i), 0, i );
     }
 
-    void shift_l( const char* in, char* out, std::size_t n, int i) {
-        FC_ASSERT( (n & 3) == 0 ); // all hashes are a multiple of 32 bit
-        n >>= 2;
-        const uint32_t* in32 = (uint32_t*) in;
-        uint32_t* out32 = (uint32_t*) out;
+    void shift_l( const char* in, char* out, std::size_t n, unsigned int i) {
+        const uint8_t* in8 = (uint8_t*) in;
+        uint8_t* out8 = (uint8_t*) out;
 
-        if (i >= 32) {
-            shift_l( in32, out32, n, i >> 5 );
-            i &= 0x1f;
-            in32 = out32;
+        if (i >= 8) {
+            shift_l( in8, out8, n, i >> 3 );
+            i &= 7;
+            in8 = out8;
         }
 
         std::size_t p;
         for( p = 0; p < n-1; ++p )
-            out32[p] = boost::endian::native_to_big(boost::endian::big_to_native(in32[p]) << i
-                                                    | (boost::endian::big_to_native(in32[p+1])>>(32-i)));
-        out32[p] = boost::endian::native_to_big(boost::endian::big_to_native(in32[p]) << i);
+            out8[p] = (in8[p] << i) | (in8[p+1]>>(8-i));
+        out8[p] = in8[p] << i;
     }
 }}
diff --git a/src/crypto/_digest_common.hpp b/src/crypto/_digest_common.hpp
index a95b76d..8aa21b3 100644
--- a/src/crypto/_digest_common.hpp
+++ b/src/crypto/_digest_common.hpp
@@ -3,5 +3,5 @@
 /* Common stuff for cryptographic hashes
  */
 namespace fc { namespace detail {
-    void shift_l( const char* in, char* out, std::size_t n, int i);
+    void shift_l( const char* in, char* out, std::size_t n, unsigned int i);
 }}