Modularize CBC-MAC

3 files changed, 155 insertions, 0 deletions

diff --git a/modules/mac/cbc_mac/cbc_mac.cpp b/modules/mac/cbc_mac/cbc_mac.cpp
new file mode 100644
index 000000000..d5275b0ed
--- /dev/null
+++ b/modules/mac/cbc_mac/cbc_mac.cpp
@@ -0,0 +1,109 @@
+/*************************************************
+* CBC-MAC Source File                            *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/cbc_mac.h>
+#include <botan/lookup.h>
+#include <botan/xor_buf.h>
+#include <algorithm>
+
+namespace Botan {
+
+/*************************************************
+* Update an CBC-MAC Calculation                  *
+*************************************************/
+void CBC_MAC::add_data(const byte input[], u32bit length)
+   {
+   u32bit xored = std::min(OUTPUT_LENGTH - position, length);
+   xor_buf(state + position, input, xored);
+   position += xored;
+
+   if(position < OUTPUT_LENGTH)
+      return;
+
+   e->encrypt(state);
+   input += xored;
+   length -= xored;
+   while(length >= OUTPUT_LENGTH)
+      {
+      xor_buf(state, input, OUTPUT_LENGTH);
+      e->encrypt(state);
+      input += OUTPUT_LENGTH;
+      length -= OUTPUT_LENGTH;
+      }
+
+   xor_buf(state, input, length);
+   position = length;
+   }
+
+/*************************************************
+* Finalize an CBC-MAC Calculation                *
+*************************************************/
+void CBC_MAC::final_result(byte mac[])
+   {
+   if(position)
+      e->encrypt(state);
+
+   copy_mem(mac, state.begin(), state.size());
+   state.clear();
+   position = 0;
+   }
+
+/*************************************************
+* CBC-MAC Key Schedule                           *
+*************************************************/
+void CBC_MAC::key(const byte key[], u32bit length)
+   {
+   e->set_key(key, length);
+   }
+
+/*************************************************
+* Clear memory of sensitive data                 *
+*************************************************/
+void CBC_MAC::clear() throw()
+   {
+   e->clear();
+   state.clear();
+   position = 0;
+   }
+
+/*************************************************
+* Return the name of this type                   *
+*************************************************/
+std::string CBC_MAC::name() const
+   {
+   return "CBC-MAC(" + e->name() + ")";
+   }
+
+/*************************************************
+* Return a clone of this object                  *
+*************************************************/
+MessageAuthenticationCode* CBC_MAC::clone() const
+   {
+   return new CBC_MAC(e->name());
+   }
+
+/*************************************************
+* CBC-MAC Constructor                            *
+*************************************************/
+CBC_MAC::CBC_MAC(const std::string& cipher) :
+   MessageAuthenticationCode(block_size_of(cipher),
+                             min_keylength_of(cipher),
+                             max_keylength_of(cipher),
+                             keylength_multiple_of(cipher)),
+   state(block_size_of(cipher))
+   {
+   e = get_block_cipher(cipher);
+   position = 0;
+   }
+
+/*************************************************
+* CBC-MAC Destructor                             *
+*************************************************/
+CBC_MAC::~CBC_MAC()
+   {
+   delete e;
+   }
+
+}
diff --git a/modules/mac/cbc_mac/cbc_mac.h b/modules/mac/cbc_mac/cbc_mac.h
new file mode 100644
index 000000000..a5646d07a
--- /dev/null
+++ b/modules/mac/cbc_mac/cbc_mac.h
@@ -0,0 +1,36 @@
+/*************************************************
+* CBC-MAC Header File                            *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_CBC_MAC__
+#define BOTAN_CBC_MAC__
+
+#include <botan/base.h>
+
+namespace Botan {
+
+/*************************************************
+* CBC-MAC                                        *
+*************************************************/
+class BOTAN_DLL CBC_MAC : public MessageAuthenticationCode
+   {
+   public:
+      void clear() throw();
+      std::string name() const;
+      MessageAuthenticationCode* clone() const;
+      CBC_MAC(const std::string&);
+      ~CBC_MAC();
+   private:
+      void add_data(const byte[], u32bit);
+      void final_result(byte[]);
+      void key(const byte[], u32bit);
+
+      BlockCipher* e;
+      SecureVector<byte> state;
+      u32bit position;
+   };
+
+}
+
+#endif
diff --git a/modules/mac/cbc_mac/modinfo.txt b/modules/mac/cbc_mac/modinfo.txt
new file mode 100644
index 000000000..3a7a6e781
--- /dev/null
+++ b/modules/mac/cbc_mac/modinfo.txt
@@ -0,0 +1,10 @@
+realname "CBC-MAC"
+
+define CBC_MAC
+
+load_on auto
+
+<add>
+cbc_mac.cpp
+cbc_mac.h
+</add>