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Diffstat (limited to 'src/plugins/crypto_ia32/ghash.h')
| -rw-r--r-- | src/plugins/crypto_ia32/ghash.h | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/src/plugins/crypto_ia32/ghash.h b/src/plugins/crypto_ia32/ghash.h new file mode 100644 index 00000000000..0b2f629e28a --- /dev/null +++ b/src/plugins/crypto_ia32/ghash.h @@ -0,0 +1,253 @@ +/* + *------------------------------------------------------------------ + * Copyright (c) 2019 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + *------------------------------------------------------------------ + */ + +/* + *------------------------------------------------------------------ + * Copyright(c) 2018, Intel Corporation All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES * LOSS OF USE, + * DATA, OR PROFITS * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + *------------------------------------------------------------------ + */ + +/* + * Based on work by: Shay Gueron, Michael E. Kounavis, Erdinc Ozturk, + * Vinodh Gopal, James Guilford, Tomasz Kantecki + * + * References: + * [1] Vinodh Gopal et. al. Optimized Galois-Counter-Mode Implementation on + * Intel Architecture Processors. August, 2010 + * [2] Erdinc Ozturk et. al. Enabling High-Performance Galois-Counter-Mode on + * Intel Architecture Processors. October, 2012. + * [3] intel-ipsec-mb library, https://github.com/01org/intel-ipsec-mb.git + * + * Definitions: + * GF Galois Extension Field GF(2^128) - finite field where elements are + * represented as polynomials with coefficients in GF(2) with the + * highest degree of 127. Polynomials are represented as 128-bit binary + * numbers where each bit represents one coefficient. + * e.g. polynomial x^5 + x^3 + x + 1 is represented in binary 101011. + * H hash key (128 bit) + * POLY irreducible polynomial x^127 + x^7 + x^2 + x + 1 + * RPOLY irreducible polynomial x^128 + x^127 + x^126 + x^121 + 1 + * + addition in GF, which equals to XOR operation + * * multiplication in GF + * + * GF multiplication consists of 2 steps: + * - carry-less multiplication of two 128-bit operands into 256-bit result + * - reduction of 256-bit result into 128-bit with modulo POLY + * + * GHash is calculated on 128-bit blocks of data according to the following + * formula: + * GH = (GH + data) * hash_key + * + * To avoid bit-reflection of data, this code uses GF multipication + * with reversed polynomial: + * a * b * x^-127 mod RPOLY + * + * To improve computation speed table Hi is precomputed with powers of H', + * where H' is calculated as H<<1 mod RPOLY. + * This allows us to improve performance by deferring reduction. For example + * to caclulate ghash of 4 128-bit blocks of data (b0, b1, b2, b3), we can do: + * + * __i128 Hi[4]; + * ghash_precompute (H, Hi, 4); + * + * ghash_data_t _gd, *gd = &_gd; + * ghash_mul_first (gd, GH ^ b0, Hi[3]); + * ghash_mul_next (gd, b1, Hi[2]); + * ghash_mul_next (gd, b2, Hi[1]); + * ghash_mul_next (gd, b3, Hi[0]); + * ghash_reduce (gd); + * ghash_reduce2 (gd); + * GH = ghash_final (gd); + * + * Reduction step is split into 3 functions so it can be better interleaved + * with other code, (i.e. with AES computation). + */ + +#ifndef __ghash_h__ +#define __ghash_h__ + +/* on AVX-512 systems we can save a clock cycle by using ternary logic + instruction to calculate a XOR b XOR c */ +static_always_inline __m128i +ghash_xor3 (__m128i a, __m128i b, __m128i c) +{ +#if defined (__AVX512F__) + return _mm_ternarylogic_epi32 (a, b, c, 0x96); +#endif + return a ^ b ^ c; +} + +typedef struct +{ + __m128i mid, hi, lo, tmp_lo, tmp_hi; + int pending; +} ghash_data_t; + +static const __m128i ghash_poly = { 1, 0xC200000000000000 }; +static const __m128i ghash_poly2 = { 0x1C2000000, 0xC200000000000000 }; + +static_always_inline void +ghash_mul_first (ghash_data_t * gd, __m128i a, __m128i b) +{ + /* a1 * b1 */ + gd->hi = _mm_clmulepi64_si128 (a, b, 0x11); + /* a0 * b0 */ + gd->lo = _mm_clmulepi64_si128 (a, b, 0x00); + /* a0 * b1 ^ a1 * b0 */ + gd->mid = (_mm_clmulepi64_si128 (a, b, 0x01) ^ + _mm_clmulepi64_si128 (a, b, 0x10)); + + /* set gd->pending to 0 so next invocation of ghash_mul_next(...) knows that + there is no pending data in tmp_lo and tmp_hi */ + gd->pending = 0; +} + +static_always_inline void +ghash_mul_next (ghash_data_t * gd, __m128i a, __m128i b) +{ + /* a1 * b1 */ + __m128i hi = _mm_clmulepi64_si128 (a, b, 0x11); + /* a0 * b0 */ + __m128i lo = _mm_clmulepi64_si128 (a, b, 0x00); + + /* this branch will be optimized out by the compiler, and it allows us to + reduce number of XOR operations by using ternary logic */ + if (gd->pending) + { + /* there is peding data from previous invocation so we can XOR */ + gd->hi = ghash_xor3 (gd->hi, gd->tmp_hi, hi); + gd->lo = ghash_xor3 (gd->lo, gd->tmp_lo, lo); + gd->pending = 0; + } + else + { + /* there is no peding data from previous invocation so we postpone XOR */ + gd->tmp_hi = hi; + gd->tmp_lo = lo; + gd->pending = 1; + } + + /* gd->mid ^= a0 * b1 ^ a1 * b0 */ + gd->mid = ghash_xor3 (gd->mid, + _mm_clmulepi64_si128 (a, b, 0x01), + _mm_clmulepi64_si128 (a, b, 0x10)); +} + +static_always_inline void +ghash_reduce (ghash_data_t * gd) +{ + __m128i r; + + /* Final combination: + gd->lo ^= gd->mid << 64 + gd->hi ^= gd->mid >> 64 */ + __m128i midl = _mm_slli_si128 (gd->mid, 8); + __m128i midr = _mm_srli_si128 (gd->mid, 8); + + if (gd->pending) + { + gd->lo = ghash_xor3 (gd->lo, gd->tmp_lo, midl); + gd->hi = ghash_xor3 (gd->hi, gd->tmp_hi, midr); + } + else + { + gd->lo ^= midl; + gd->hi ^= midr; + } + + r = _mm_clmulepi64_si128 (ghash_poly2, gd->lo, 0x01); + gd->lo ^= _mm_slli_si128 (r, 8); +} + +static_always_inline void +ghash_reduce2 (ghash_data_t * gd) +{ + gd->tmp_lo = _mm_clmulepi64_si128 (ghash_poly2, gd->lo, 0x00); + gd->tmp_hi = _mm_clmulepi64_si128 (ghash_poly2, gd->lo, 0x10); +} + +static_always_inline __m128i +ghash_final (ghash_data_t * gd) +{ + return ghash_xor3 (gd->hi, _mm_srli_si128 (gd->tmp_lo, 4), + _mm_slli_si128 (gd->tmp_hi, 4)); +} + +static_always_inline __m128i +ghash_mul (__m128i a, __m128i b) +{ + ghash_data_t _gd, *gd = &_gd; + ghash_mul_first (gd, a, b); + ghash_reduce (gd); + ghash_reduce2 (gd); + return ghash_final (gd); +} + +static_always_inline void +ghash_precompute (__m128i H, __m128i * Hi, int count) +{ + __m128i r; + /* calcullate H<<1 mod poly from the hash key */ + r = _mm_srli_epi64 (H, 63); + H = _mm_slli_epi64 (H, 1); + H |= _mm_slli_si128 (r, 8); + r = _mm_srli_si128 (r, 8); + r = _mm_shuffle_epi32 (r, 0x24); + /* *INDENT-OFF* */ + r = _mm_cmpeq_epi32 (r, (__m128i) (u32x4) {1, 0, 0, 1}); + /* *INDENT-ON* */ + Hi[0] = H ^ (r & ghash_poly); + + /* calculate H^(i + 1) */ + for (int i = 1; i < count; i++) + Hi[i] = ghash_mul (Hi[0], Hi[i - 1]); +} + +#endif /* __ghash_h__ */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |