From e33e19d0587146859d48a134ec9fd94e7b7ba5cd Mon Sep 17 00:00:00 2001
From: "FWoltermann@gmail.com"
 <FWoltermann@gmail.com@076cb2c4-205e-83fd-5cf3-1be9aa105544>
Date: Thu, 8 Dec 2011 14:53:40 +0000
Subject: Initial upload

---
 nGenEx/Encrypt.cpp | 171 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 171 insertions(+)
 create mode 100644 nGenEx/Encrypt.cpp

(limited to 'nGenEx/Encrypt.cpp')

diff --git a/nGenEx/Encrypt.cpp b/nGenEx/Encrypt.cpp
new file mode 100644
index 0000000..6fa79d2
--- /dev/null
+++ b/nGenEx/Encrypt.cpp
@@ -0,0 +1,171 @@
+/*  Project nGenEx
+    Destroyer Studios LLC
+    Copyright © 1997-2004. All Rights Reserved.
+
+    SUBSYSTEM:    nGenEx.lib
+    FILE:         Encrypt.cpp
+    AUTHOR:       John DiCamillo
+
+
+    OVERVIEW
+    ========
+    Simple Encryption / Decryption class
+*/
+
+
+#include "MemDebug.h"
+#include "Encrypt.h"
+
+// +--------------------------------------------------------------------+
+
+void Print(const char* fmt, ...);
+
+static long k[4] = {
+   0x3B398E26,
+   0x40C29501,
+   0x614D7630,
+   0x7F59409A
+};
+
+static void encypher(long* v)
+{
+   DWORD y=v[0];
+   DWORD z=v[1];
+   DWORD sum=0;
+   DWORD delta=0x9e3779b9;                // a key schedule constant
+   DWORD n=32;                            // num iterations
+
+   while (n-->0) {                        // basic cycle start
+      sum += delta;
+      y += (z<<4)+k[0] ^ z+sum ^ (z>>5)+k[1];
+      z += (y<<4)+k[2] ^ y+sum ^ (y>>5)+k[3];
+   }
+
+   v[0]=y;
+   v[1]=z;
+}
+
+static void decypher(long* v)
+{
+   DWORD y=v[0];
+   DWORD z=v[1];
+   DWORD sum=0;
+   DWORD delta=0x9e3779b9;                // a key schedule constant
+   DWORD n=32;                            // num iterations
+
+   sum=delta<<5;
+
+   while (n-->0) {
+      z-= (y<<4)+k[2] ^ y+sum ^ (y>>5)+k[3]; 
+      y-= (z<<4)+k[0] ^ z+sum ^ (z>>5)+k[1];
+      sum-=delta;
+   }
+
+   v[0]=y;
+   v[1]=z;
+}
+
+// +-------------------------------------------------------------------+
+
+Text 
+Encryption::Encrypt(Text block)
+{
+   int len = block.length();
+
+   if (len < 1)
+      return Text();
+
+   // pad to eight byte chunks
+   if (len & 0x7) {
+      len /= 8;
+      len *= 8;
+      len += 8;
+   }
+
+   BYTE* work = new(__FILE__,__LINE__) BYTE[len];
+   ZeroMemory(work, len);
+   CopyMemory(work, block.data(), block.length());
+
+   long* v = (long*) work;
+   for (int i = 0; i < len/8; i++) {
+      encypher(v);
+      v += 2;
+   }
+
+   Text cypher((const char*) work, len);
+   delete [] work;
+   return cypher;
+}
+
+// +-------------------------------------------------------------------+
+
+Text 
+Encryption::Decrypt(Text block)
+{
+   int  len    = block.length();
+
+   if (len & 0x7) {
+      Print("WARNING: attempt to decrypt odd length block (len=%d)\n", len);
+      return Text();
+   }
+
+   BYTE* work = new(__FILE__,__LINE__) BYTE[len];
+   CopyMemory(work, block.data(), len);
+
+   long* v = (long*) work;
+   for (int i = 0; i < len/8; i++) {
+      decypher(v);
+      v += 2;
+   }
+
+   Text clear((const char*) work, len);
+   delete [] work;
+   return clear;
+}
+
+// +-------------------------------------------------------------------+
+
+static const char* codes = "abcdefghijklmnop";
+
+Text 
+Encryption::Encode(Text block)
+{
+   int   len  = block.length() * 2;
+   char* work = new(__FILE__,__LINE__) char[len + 1];
+
+   for (int i = 0; i < block.length(); i++) {
+      BYTE b = (BYTE) (block.data()[i]);
+      work[2*i]   = codes[b>>4 & 0xf];
+      work[2*i+1] = codes[b    & 0xf];
+   }
+
+   work[len] = 0;
+
+   Text code(work, len);
+   delete [] work;
+   return code;
+}
+
+// +-------------------------------------------------------------------+
+
+Text 
+Encryption::Decode(Text block)
+{
+   int   len  = block.length() / 2;
+   char* work = new(__FILE__,__LINE__) char[len + 1];
+
+   for (int i = 0; i < len; i++) {
+      char u = block[2*i];
+      char l = block[2*i + 1];
+
+      work[i] = (u - codes[0]) << 4 |
+                (l - codes[0]);
+   }
+
+   work[len] = 0;
+
+   Text clear(work, len);
+   delete [] work;
+   return clear;
+}
+
-- 
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