1 files changed, 64 insertions, 0 deletions
diff --git a/old/botan/src/block/xtea/xtea.cpp b/old/botan/src/block/xtea/xtea.cpp
new file mode 100644
index 0000000..5047f65
--- /dev/null
+++ b/old/botan/src/block/xtea/xtea.cpp
@@ -0,0 +1,64 @@
+/*
+* XTEA
+* (C) 1999-2009 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/xtea.h>
+#include <botan/loadstor.h>
+#include <botan/parsing.h>
+
+namespace Botan {
+
+/*
+* XTEA Encryption
+*/
+void XTEA::enc(const byte in[], byte out[]) const
+   {
+   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
+
+   for(u32bit j = 0; j != 32; ++j)
+      {
+      L += (((R << 4) ^ (R >> 5)) + R) ^ EK[2*j];
+      R += (((L << 4) ^ (L >> 5)) + L) ^ EK[2*j+1];
+      }
+
+   store_be(out, L, R);
+   }
+
+/*
+* XTEA Decryption
+*/
+void XTEA::dec(const byte in[], byte out[]) const
+   {
+   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
+
+   for(u32bit j = 0; j != 32; ++j)
+      {
+      R -= (((L << 4) ^ (L >> 5)) + L) ^ EK[63 - 2*j];
+      L -= (((R << 4) ^ (R >> 5)) + R) ^ EK[62 - 2*j];
+      }
+
+   store_be(out, L, R);
+   }
+
+/*
+* XTEA Key Schedule
+*/
+void XTEA::key_schedule(const byte key[], u32bit)
+   {
+   SecureBuffer<u32bit, 4> UK;
+   for(u32bit i = 0; i != 4; ++i)
+      UK[i] = load_be<u32bit>(key, i);
+
+   u32bit D = 0;
+   for(u32bit i = 0; i != 64; i += 2)
+      {
+      EK[i  ] = D + UK[D % 4];
+      D += 0x9E3779B9;
+      EK[i+1] = D + UK[(D >> 11) % 4];
+      }
+   }
+
+}