/* * IDEA in SSE2 * (C) 2009 Jack Lloyd * * Distributed under the terms of the Botan license */ #include #include namespace Botan { namespace { inline __m128i mul(__m128i X, u16bit K_16) { const __m128i zeros = _mm_set1_epi16(0); const __m128i ones = _mm_set1_epi16(1); const __m128i K = _mm_set1_epi16(K_16); const __m128i X_is_zero = _mm_cmpeq_epi16(X, zeros); const __m128i K_is_zero = _mm_cmpeq_epi16(K, zeros); const __m128i mul_lo = _mm_mullo_epi16(X, K); const __m128i mul_hi = _mm_mulhi_epu16(X, K); __m128i T = _mm_sub_epi16(mul_lo, mul_hi); // Unsigned compare; cmp = 1 if mul_lo < mul_hi else 0 const __m128i subs = _mm_subs_epu16(mul_hi, mul_lo); const __m128i cmp = _mm_min_epu8( _mm_or_si128(subs, _mm_srli_epi16(subs, 8)), ones); T = _mm_add_epi16(T, cmp); /* Selection: if X[i] is zero then assign 1-K if K is zero then assign 1-X[i] Could if() off value of K_16 for the second, but this gives a constant time implementation which is a nice bonus. */ T = _mm_or_si128( _mm_andnot_si128(X_is_zero, T), _mm_and_si128(_mm_sub_epi16(ones, K), X_is_zero)); T = _mm_or_si128( _mm_andnot_si128(K_is_zero, T), _mm_and_si128(_mm_sub_epi16(ones, X), K_is_zero)); return T; } /* * 4x8 matrix transpose * * FIXME: why do I need the extra set of unpack_epi32 here? Inverse in * transpose_out doesn't need it. Something with the shuffle? Removing * that extra unpack could easily save 3-4 cycles per block, and would * also help a lot with register pressure on 32-bit x86 */ void transpose_in(__m128i& B0, __m128i& B1, __m128i& B2, __m128i& B3) { __m128i T0 = _mm_unpackhi_epi32(B0, B1); __m128i T1 = _mm_unpacklo_epi32(B0, B1); __m128i T2 = _mm_unpackhi_epi32(B2, B3); __m128i T3 = _mm_unpacklo_epi32(B2, B3); __m128i T4 = _mm_unpacklo_epi32(T0, T1); __m128i T5 = _mm_unpackhi_epi32(T0, T1); __m128i T6 = _mm_unpacklo_epi32(T2, T3); __m128i T7 = _mm_unpackhi_epi32(T2, T3); T0 = _mm_shufflehi_epi16(T4, _MM_SHUFFLE(1, 3, 0, 2)); T1 = _mm_shufflehi_epi16(T5, _MM_SHUFFLE(1, 3, 0, 2)); T2 = _mm_shufflehi_epi16(T6, _MM_SHUFFLE(1, 3, 0, 2)); T3 = _mm_shufflehi_epi16(T7, _MM_SHUFFLE(1, 3, 0, 2)); T0 = _mm_shufflelo_epi16(T0, _MM_SHUFFLE(1, 3, 0, 2)); T1 = _mm_shufflelo_epi16(T1, _MM_SHUFFLE(1, 3, 0, 2)); T2 = _mm_shufflelo_epi16(T2, _MM_SHUFFLE(1, 3, 0, 2)); T3 = _mm_shufflelo_epi16(T3, _MM_SHUFFLE(1, 3, 0, 2)); T0 = _mm_shuffle_epi32(T0, _MM_SHUFFLE(3, 1, 2, 0)); T1 = _mm_shuffle_epi32(T1, _MM_SHUFFLE(3, 1, 2, 0)); T2 = _mm_shuffle_epi32(T2, _MM_SHUFFLE(3, 1, 2, 0)); T3 = _mm_shuffle_epi32(T3, _MM_SHUFFLE(3, 1, 2, 0)); B0 = _mm_unpacklo_epi64(T0, T2); B1 = _mm_unpackhi_epi64(T0, T2); B2 = _mm_unpacklo_epi64(T1, T3); B3 = _mm_unpackhi_epi64(T1, T3); } /* * 4x8 matrix transpose (reverse) */ void transpose_out(__m128i& B0, __m128i& B1, __m128i& B2, __m128i& B3) { __m128i T0 = _mm_unpacklo_epi64(B0, B1); __m128i T1 = _mm_unpacklo_epi64(B2, B3); __m128i T2 = _mm_unpackhi_epi64(B0, B1); __m128i T3 = _mm_unpackhi_epi64(B2, B3); T0 = _mm_shuffle_epi32(T0, _MM_SHUFFLE(3, 1, 2, 0)); T1 = _mm_shuffle_epi32(T1, _MM_SHUFFLE(3, 1, 2, 0)); T2 = _mm_shuffle_epi32(T2, _MM_SHUFFLE(3, 1, 2, 0)); T3 = _mm_shuffle_epi32(T3, _MM_SHUFFLE(3, 1, 2, 0)); T0 = _mm_shufflehi_epi16(T0, _MM_SHUFFLE(3, 1, 2, 0)); T1 = _mm_shufflehi_epi16(T1, _MM_SHUFFLE(3, 1, 2, 0)); T2 = _mm_shufflehi_epi16(T2, _MM_SHUFFLE(3, 1, 2, 0)); T3 = _mm_shufflehi_epi16(T3, _MM_SHUFFLE(3, 1, 2, 0)); T0 = _mm_shufflelo_epi16(T0, _MM_SHUFFLE(3, 1, 2, 0)); T1 = _mm_shufflelo_epi16(T1, _MM_SHUFFLE(3, 1, 2, 0)); T2 = _mm_shufflelo_epi16(T2, _MM_SHUFFLE(3, 1, 2, 0)); T3 = _mm_shufflelo_epi16(T3, _MM_SHUFFLE(3, 1, 2, 0)); B0 = _mm_unpacklo_epi32(T0, T1); B1 = _mm_unpackhi_epi32(T0, T1); B2 = _mm_unpacklo_epi32(T2, T3); B3 = _mm_unpackhi_epi32(T2, T3); } /* * IDEA encryption/decryption in SSE2 */ void idea_op_8(const byte in[64], byte out[64], const u16bit EK[52]) { const __m128i* in_mm = reinterpret_cast(in); __m128i B0 = _mm_loadu_si128(in_mm + 0); __m128i B1 = _mm_loadu_si128(in_mm + 1); __m128i B2 = _mm_loadu_si128(in_mm + 2); __m128i B3 = _mm_loadu_si128(in_mm + 3); transpose_in(B0, B1, B2, B3); // byte swap B0 = _mm_or_si128(_mm_slli_epi16(B0, 8), _mm_srli_epi16(B0, 8)); B1 = _mm_or_si128(_mm_slli_epi16(B1, 8), _mm_srli_epi16(B1, 8)); B2 = _mm_or_si128(_mm_slli_epi16(B2, 8), _mm_srli_epi16(B2, 8)); B3 = _mm_or_si128(_mm_slli_epi16(B3, 8), _mm_srli_epi16(B3, 8)); for(size_t i = 0; i != 8; ++i) { B0 = mul(B0, EK[6*i+0]); B1 = _mm_add_epi16(B1, _mm_set1_epi16(EK[6*i+1])); B2 = _mm_add_epi16(B2, _mm_set1_epi16(EK[6*i+2])); B3 = mul(B3, EK[6*i+3]); __m128i T0 = B2; B2 = _mm_xor_si128(B2, B0); B2 = mul(B2, EK[6*i+4]); __m128i T1 = B1; B1 = _mm_xor_si128(B1, B3); B1 = _mm_add_epi16(B1, B2); B1 = mul(B1, EK[6*i+5]); B2 = _mm_add_epi16(B2, B1); B0 = _mm_xor_si128(B0, B1); B1 = _mm_xor_si128(B1, T0); B3 = _mm_xor_si128(B3, B2); B2 = _mm_xor_si128(B2, T1); } B0 = mul(B0, EK[48]); B1 = _mm_add_epi16(B1, _mm_set1_epi16(EK[50])); B2 = _mm_add_epi16(B2, _mm_set1_epi16(EK[49])); B3 = mul(B3, EK[51]); // byte swap B0 = _mm_or_si128(_mm_slli_epi16(B0, 8), _mm_srli_epi16(B0, 8)); B1 = _mm_or_si128(_mm_slli_epi16(B1, 8), _mm_srli_epi16(B1, 8)); B2 = _mm_or_si128(_mm_slli_epi16(B2, 8), _mm_srli_epi16(B2, 8)); B3 = _mm_or_si128(_mm_slli_epi16(B3, 8), _mm_srli_epi16(B3, 8)); transpose_out(B0, B2, B1, B3); __m128i* out_mm = reinterpret_cast<__m128i*>(out); _mm_storeu_si128(out_mm + 0, B0); _mm_storeu_si128(out_mm + 1, B2); _mm_storeu_si128(out_mm + 2, B1); _mm_storeu_si128(out_mm + 3, B3); } } /* * IDEA Encryption */ void IDEA_SSE2::encrypt_n(const byte in[], byte out[], size_t blocks) const { const u16bit* KS = &this->get_EK()[0]; while(blocks >= 8) { idea_op_8(in, out, KS); in += 8 * BLOCK_SIZE; out += 8 * BLOCK_SIZE; blocks -= 8; } if(blocks) IDEA::encrypt_n(in, out, blocks); } /* * IDEA Decryption */ void IDEA_SSE2::decrypt_n(const byte in[], byte out[], size_t blocks) const { const u16bit* KS = &this->get_DK()[0]; while(blocks >= 8) { idea_op_8(in, out, KS); in += 8 * BLOCK_SIZE; out += 8 * BLOCK_SIZE; blocks -= 8; } if(blocks) IDEA::decrypt_n(in, out, blocks); } }