1 files changed, 139 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/mac/cmac/cmac.cpp b/comm/third_party/botan/src/lib/mac/cmac/cmac.cpp
new file mode 100644
index 0000000000..38752471dd
--- /dev/null
+++ b/comm/third_party/botan/src/lib/mac/cmac/cmac.cpp
@@ -0,0 +1,139 @@
+/*
+* CMAC
+* (C) 1999-2007,2014 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/cmac.h>
+#include <botan/exceptn.h>
+#include <botan/internal/poly_dbl.h>
+
+namespace Botan {
+
+/*
+* Perform CMAC's multiplication in GF(2^n)
+*/
+secure_vector<uint8_t> CMAC::poly_double(const secure_vector<uint8_t>& in)
+   {
+   secure_vector<uint8_t> out(in.size());
+   poly_double_n(out.data(), in.data(), out.size());
+   return out;
+   }
+
+/*
+* Update an CMAC Calculation
+*/
+void CMAC::add_data(const uint8_t input[], size_t length)
+   {
+   const size_t bs = output_length();
+
+   buffer_insert(m_buffer, m_position, input, length);
+   if(m_position + length > bs)
+      {
+      xor_buf(m_state, m_buffer, bs);
+      m_cipher->encrypt(m_state);
+      input += (bs - m_position);
+      length -= (bs - m_position);
+      while(length > bs)
+         {
+         xor_buf(m_state, input, bs);
+         m_cipher->encrypt(m_state);
+         input += bs;
+         length -= bs;
+         }
+      copy_mem(m_buffer.data(), input, length);
+      m_position = 0;
+      }
+   m_position += length;
+   }
+
+/*
+* Finalize an CMAC Calculation
+*/
+void CMAC::final_result(uint8_t mac[])
+   {
+   xor_buf(m_state, m_buffer, m_position);
+
+   if(m_position == output_length())
+      {
+      xor_buf(m_state, m_B, output_length());
+      }
+   else
+      {
+      m_state[m_position] ^= 0x80;
+      xor_buf(m_state, m_P, output_length());
+      }
+
+   m_cipher->encrypt(m_state);
+
+   copy_mem(mac, m_state.data(), output_length());
+
+   zeroise(m_state);
+   zeroise(m_buffer);
+   m_position = 0;
+   }
+
+/*
+* CMAC Key Schedule
+*/
+void CMAC::key_schedule(const uint8_t key[], size_t length)
+   {
+   clear();
+   m_cipher->set_key(key, length);
+   m_cipher->encrypt(m_B);
+   poly_double_n(m_B.data(), m_B.size());
+   poly_double_n(m_P.data(), m_B.data(), m_P.size());
+   }
+
+/*
+* Clear memory of sensitive data
+*/
+void CMAC::clear()
+   {
+   m_cipher->clear();
+   zeroise(m_state);
+   zeroise(m_buffer);
+   zeroise(m_B);
+   zeroise(m_P);
+   m_position = 0;
+   }
+
+/*
+* Return the name of this type
+*/
+std::string CMAC::name() const
+   {
+   return "CMAC(" + m_cipher->name() + ")";
+   }
+
+/*
+* Return a clone of this object
+*/
+MessageAuthenticationCode* CMAC::clone() const
+   {
+   return new CMAC(m_cipher->clone());
+   }
+
+/*
+* CMAC Constructor
+*/
+CMAC::CMAC(BlockCipher* cipher) :
+   m_cipher(cipher),
+   m_block_size(m_cipher->block_size())
+   {
+   if(poly_double_supported_size(m_block_size) == false)
+      {
+      throw Invalid_Argument("CMAC cannot use the " +
+                             std::to_string(m_block_size * 8) +
+                             " bit cipher " + m_cipher->name());
+      }
+
+   m_state.resize(output_length());
+   m_buffer.resize(output_length());
+   m_B.resize(output_length());
+   m_P.resize(output_length());
+   m_position = 0;
+   }
+
+}