/*
* MD4
* (C) 1999-2007 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include <botan/md4.h>
#include <botan/rotate.h>

namespace Botan {

std::unique_ptr<HashFunction> MD4::copy_state() const
   {
   return std::unique_ptr<HashFunction>(new MD4(*this));
   }

namespace {

inline void FF4(uint32_t& A, uint32_t& B, uint32_t& C, uint32_t& D,
                uint32_t M0, uint32_t M1, uint32_t M2, uint32_t M3)

   {
   A += (D ^ (B & (C ^ D))) + M0;
   A = rotl<3>(A);

   D += (C ^ (A & (B ^ C))) + M1;
   D = rotl<7>(D);

   C += (B ^ (D & (A ^ B))) + M2;
   C = rotl<11>(C);

   B += (A ^ (C & (D ^ A))) + M3;
   B = rotl<19>(B);
   }

inline void GG4(uint32_t& A, uint32_t& B, uint32_t& C, uint32_t& D,
                uint32_t M0, uint32_t M1, uint32_t M2, uint32_t M3)

   {
   A += ((B & C) | (D & (B | C))) + M0 + 0x5A827999;
   A = rotl<3>(A);

   D += ((A & B) | (C & (A | B))) + M1 + 0x5A827999;
   D = rotl<5>(D);

   C += ((D & A) | (B & (D | A))) + M2 + 0x5A827999;
   C = rotl<9>(C);

   B += ((C & D) | (A & (C | D))) + M3 + 0x5A827999;
   B = rotl<13>(B);
   }

inline void HH4(uint32_t& A, uint32_t& B, uint32_t& C, uint32_t& D,
                uint32_t M0, uint32_t M1, uint32_t M2, uint32_t M3)

   {
   A += (B ^ C ^ D) + M0 + 0x6ED9EBA1;
   A = rotl<3>(A);

   D += (A ^ B ^ C) + M1 + 0x6ED9EBA1;
   D = rotl<9>(D);

   C += (A ^ B ^ D) + M2 + 0x6ED9EBA1;
   C = rotl<11>(C);

   B += (A ^ C ^ D) + M3 + 0x6ED9EBA1;
   B = rotl<15>(B);
   }

}

/*
* MD4 Compression Function
*/
void MD4::compress_n(const uint8_t input[], size_t blocks)
   {
   uint32_t A = m_digest[0], B = m_digest[1], C = m_digest[2], D = m_digest[3];

   for(size_t i = 0; i != blocks; ++i)
      {
      uint32_t M00 = load_le<uint32_t>(input, 0);
      uint32_t M01 = load_le<uint32_t>(input, 1);
      uint32_t M02 = load_le<uint32_t>(input, 2);
      uint32_t M03 = load_le<uint32_t>(input, 3);
      uint32_t M04 = load_le<uint32_t>(input, 4);
      uint32_t M05 = load_le<uint32_t>(input, 5);
      uint32_t M06 = load_le<uint32_t>(input, 6);
      uint32_t M07 = load_le<uint32_t>(input, 7);
      uint32_t M08 = load_le<uint32_t>(input, 8);
      uint32_t M09 = load_le<uint32_t>(input, 9);
      uint32_t M10 = load_le<uint32_t>(input, 10);
      uint32_t M11 = load_le<uint32_t>(input, 11);
      uint32_t M12 = load_le<uint32_t>(input, 12);
      uint32_t M13 = load_le<uint32_t>(input, 13);
      uint32_t M14 = load_le<uint32_t>(input, 14);
      uint32_t M15 = load_le<uint32_t>(input, 15);

      FF4(A, B, C, D, M00, M01, M02, M03);
      FF4(A, B, C, D, M04, M05, M06, M07);
      FF4(A, B, C, D, M08, M09, M10, M11);
      FF4(A, B, C, D, M12, M13, M14, M15);

      GG4(A, B, C, D, M00, M04, M08, M12);
      GG4(A, B, C, D, M01, M05, M09, M13);
      GG4(A, B, C, D, M02, M06, M10, M14);
      GG4(A, B, C, D, M03, M07, M11, M15);

      HH4(A, B, C, D, M00, M08, M04, M12);
      HH4(A, B, C, D, M02, M10, M06, M14);
      HH4(A, B, C, D, M01, M09, M05, M13);
      HH4(A, B, C, D, M03, M11, M07, M15);

      A = (m_digest[0] += A);
      B = (m_digest[1] += B);
      C = (m_digest[2] += C);
      D = (m_digest[3] += D);

      input += hash_block_size();
      }
   }

/*
* Copy out the digest
*/
void MD4::copy_out(uint8_t output[])
   {
   copy_out_vec_le(output, output_length(), m_digest);
   }

/*
* Clear memory of sensitive data
*/
void MD4::clear()
   {
   MDx_HashFunction::clear();
   m_digest[0] = 0x67452301;
   m_digest[1] = 0xEFCDAB89;
   m_digest[2] = 0x98BADCFE;
   m_digest[3] = 0x10325476;
   }

}