/*

* SHACAL-2

* (C) 2017 Jack Lloyd

*

* Botan is released under the Simplified BSD License (see license.txt)

*/

#include <botan/shacal2.h>

#include <botan/loadstor.h>

#include <botan/rotate.h>

#include <botan/cpuid.h>

namespace Botan {

namespace {

inline void SHACAL2_Fwd(uint32_t A, uint32_t B, uint32_t C, uint32_t& D,

                        uint32_t E, uint32_t F, uint32_t G, uint32_t& H,

                        uint32_t RK)

   {

   const uint32_t A_rho = rotr<2>(A) ^ rotr<13>(A) ^ rotr<22>(A);

   const uint32_t E_rho = rotr<6>(E) ^ rotr<11>(E) ^ rotr<25>(E);

   H += E_rho + ((E & F) ^ (~E & G)) + RK;

   D += H;

   H += A_rho + ((A & B) | ((A | B) & C));

   }

inline void SHACAL2_Rev(uint32_t A, uint32_t B, uint32_t C, uint32_t& D,

                        uint32_t E, uint32_t F, uint32_t G, uint32_t& H,

                        uint32_t RK)

   {

   const uint32_t A_rho = rotr<2>(A) ^ rotr<13>(A) ^ rotr<22>(A);

   const uint32_t E_rho = rotr<6>(E) ^ rotr<11>(E) ^ rotr<25>(E);

   H -= A_rho + ((A & B) | ((A | B) & C));

   D -= H;

   H -= E_rho + ((E & F) ^ (~E & G)) + RK;

   }

}

/*

* SHACAL2 Encryption

*/

void SHACAL2::encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const

   {

   verify_key_set(m_RK.empty() == false);

#if defined(BOTAN_HAS_SHACAL2_X86)

   if(CPUID::has_intel_sha())

      {

      return x86_encrypt_blocks(in, out, blocks);

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_AVX2)

   if(CPUID::has_avx2())

      {

      while(blocks >= 8)

         {

         avx2_encrypt_8(in, out);

         in += 8*BLOCK_SIZE;

         out += 8*BLOCK_SIZE;

         blocks -= 8;

         }

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_SIMD)

   if(CPUID::has_simd_32())

      {

      while(blocks >= 4)

         {

         simd_encrypt_4(in, out);

         in += 4*BLOCK_SIZE;

         out += 4*BLOCK_SIZE;

         blocks -= 4;

         }

      }

#endif

   for(size_t i = 0; i != blocks; ++i)

      {

      uint32_t A = load_be<uint32_t>(in, 0);

      uint32_t B = load_be<uint32_t>(in, 1);

      uint32_t C = load_be<uint32_t>(in, 2);

      uint32_t D = load_be<uint32_t>(in, 3);

      uint32_t E = load_be<uint32_t>(in, 4);

      uint32_t F = load_be<uint32_t>(in, 5);

      uint32_t G = load_be<uint32_t>(in, 6);

      uint32_t H = load_be<uint32_t>(in, 7);

      for(size_t r = 0; r != 64; r += 8)

         {

         SHACAL2_Fwd(A, B, C, D, E, F, G, H, m_RK[r+0]);

         SHACAL2_Fwd(H, A, B, C, D, E, F, G, m_RK[r+1]);

         SHACAL2_Fwd(G, H, A, B, C, D, E, F, m_RK[r+2]);

         SHACAL2_Fwd(F, G, H, A, B, C, D, E, m_RK[r+3]);

         SHACAL2_Fwd(E, F, G, H, A, B, C, D, m_RK[r+4]);

         SHACAL2_Fwd(D, E, F, G, H, A, B, C, m_RK[r+5]);

         SHACAL2_Fwd(C, D, E, F, G, H, A, B, m_RK[r+6]);

         SHACAL2_Fwd(B, C, D, E, F, G, H, A, m_RK[r+7]);

         }

      store_be(out, A, B, C, D, E, F, G, H);

      in += BLOCK_SIZE;

      out += BLOCK_SIZE;

      }

   }

/*

* SHACAL2 Encryption

*/

void SHACAL2::decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const

   {

   verify_key_set(m_RK.empty() == false);

#if defined(BOTAN_HAS_SHACAL2_AVX2)

   if(CPUID::has_avx2())

      {

      while(blocks >= 8)

         {

         avx2_decrypt_8(in, out);

         in += 8*BLOCK_SIZE;

         out += 8*BLOCK_SIZE;

         blocks -= 8;

         }

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_SIMD)

   if(CPUID::has_simd_32())

      {

      while(blocks >= 4)

         {

         simd_decrypt_4(in, out);

         in += 4*BLOCK_SIZE;

         out += 4*BLOCK_SIZE;

         blocks -= 4;

         }

      }

#endif

   for(size_t i = 0; i != blocks; ++i)

      {

      uint32_t A = load_be<uint32_t>(in, 0);

      uint32_t B = load_be<uint32_t>(in, 1);

      uint32_t C = load_be<uint32_t>(in, 2);

      uint32_t D = load_be<uint32_t>(in, 3);

      uint32_t E = load_be<uint32_t>(in, 4);

      uint32_t F = load_be<uint32_t>(in, 5);

      uint32_t G = load_be<uint32_t>(in, 6);

      uint32_t H = load_be<uint32_t>(in, 7);

      for(size_t r = 0; r != 64; r += 8)

         {

         SHACAL2_Rev(B, C, D, E, F, G, H, A, m_RK[63-r]);

         SHACAL2_Rev(C, D, E, F, G, H, A, B, m_RK[62-r]);

         SHACAL2_Rev(D, E, F, G, H, A, B, C, m_RK[61-r]);

         SHACAL2_Rev(E, F, G, H, A, B, C, D, m_RK[60-r]);

         SHACAL2_Rev(F, G, H, A, B, C, D, E, m_RK[59-r]);

         SHACAL2_Rev(G, H, A, B, C, D, E, F, m_RK[58-r]);

         SHACAL2_Rev(H, A, B, C, D, E, F, G, m_RK[57-r]);

         SHACAL2_Rev(A, B, C, D, E, F, G, H, m_RK[56-r]);

         }

      store_be(out, A, B, C, D, E, F, G, H);

      in += BLOCK_SIZE;

      out += BLOCK_SIZE;

      }

   }

/*

* SHACAL2 Key Schedule

*/

void SHACAL2::key_schedule(const uint8_t key[], size_t len)

   {

   const uint32_t RC[64] = {

      0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5,

      0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5,

      0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3,

      0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174,

      0xE49B69C1, 0xEFBE4786, 0x0FC19DC6, 0x240CA1CC,

      0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA,

      0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7,

      0xC6E00BF3, 0xD5A79147, 0x06CA6351, 0x14292967,

      0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13,

      0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85,

      0xA2BFE8A1, 0xA81A664B, 0xC24B8B70, 0xC76C51A3,

      0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070,

      0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5,

      0x391C0CB3, 0x4ED8AA4A, 0x5B9CCA4F, 0x682E6FF3,

      0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208,

      0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2

   };

   if(m_RK.empty())

      m_RK.resize(64);

   else

      clear_mem(m_RK.data(), m_RK.size());

   load_be(m_RK.data(), key, len/4);

   for(size_t i = 16; i != 64; ++i)

      {

      const uint32_t sigma0_15 = rotr< 7>(m_RK[i-15]) ^ rotr<18>(m_RK[i-15]) ^ (m_RK[i-15] >> 3);

      const uint32_t sigma1_2  = rotr<17>(m_RK[i- 2]) ^ rotr<19>(m_RK[i- 2]) ^ (m_RK[i- 2] >> 10);

      m_RK[i] = m_RK[i-16] + sigma0_15 + m_RK[i-7] + sigma1_2;

      }

   for(size_t i = 0; i != 64; ++i)

      {

      m_RK[i] += RC[i];

      }

   }

size_t SHACAL2::parallelism() const

   {

#if defined(BOTAN_HAS_SHACAL2_X86)

   if(CPUID::has_intel_sha())

      {

      return 4;

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_AVX2)

   if(CPUID::has_avx2())

      {

      return 8;

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_SIMD)

   if(CPUID::has_simd_32())

      {

      return 4;

      }

#endif

   return 1;

   }

std::string SHACAL2::provider() const

   {

#if defined(BOTAN_HAS_SHACAL2_X86)

   if(CPUID::has_intel_sha())

      {

      return "intel_sha";

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_AVX2)

   if(CPUID::has_avx2())

      {

      return "avx2";

      }

#endif

#if defined(BOTAN_HAS_SHACAL2_SIMD)

   if(CPUID::has_simd_32())

      {

      return "simd";

      }

#endif

   return "base";

   }

/*

* Clear memory of sensitive data

*/

void SHACAL2::clear()

   {

   zap(m_RK);

   }

}