1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
//! SHA-512 `x86`/`x86_64` backend

#![allow(clippy::many_single_char_names)]

use core::mem::size_of;

#[cfg(target_arch = "x86")]
use core::arch::x86::*;
#[cfg(target_arch = "x86_64")]
use core::arch::x86_64::*;

use crate::consts::K64;

cpufeatures::new!(avx2_cpuid, "avx2");

pub fn compress(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
    // TODO: Replace with https://github.com/rust-lang/rfcs/pull/2725
    // after stabilization
    if avx2_cpuid::get() {
        unsafe {
            sha512_compress_x86_64_avx2(state, blocks);
        }
    } else {
        super::soft::compress(state, blocks);
    }
}

#[target_feature(enable = "avx2")]
unsafe fn sha512_compress_x86_64_avx2(state: &mut [u64; 8], blocks: &[[u8; 128]]) {
    let mut start_block = 0;

    if blocks.len() & 0b1 != 0 {
        sha512_compress_x86_64_avx(state, &blocks[0]);
        start_block += 1;
    }

    let mut ms: MsgSchedule = [_mm_setzero_si128(); 8];
    let mut t2: RoundStates = [_mm_setzero_si128(); 40];
    let mut x = [_mm256_setzero_si256(); 8];

    for i in (start_block..blocks.len()).step_by(2) {
        load_data_avx2(&mut x, &mut ms, &mut t2, blocks.as_ptr().add(i) as *const _);

        // First block
        let mut current_state = *state;
        rounds_0_63_avx2(&mut current_state, &mut x, &mut ms, &mut t2);
        rounds_64_79(&mut current_state, &ms);
        accumulate_state(state, &current_state);

        // Second block
        current_state = *state;
        process_second_block(&mut current_state, &t2);
        accumulate_state(state, &current_state);
    }
}

#[inline(always)]
unsafe fn sha512_compress_x86_64_avx(state: &mut [u64; 8], block: &[u8; 128]) {
    let mut ms = [_mm_setzero_si128(); 8];
    let mut x = [_mm_setzero_si128(); 8];

    // Reduced to single iteration
    let mut current_state = *state;
    load_data_avx(&mut x, &mut ms, block.as_ptr() as *const _);
    rounds_0_63_avx(&mut current_state, &mut x, &mut ms);
    rounds_64_79(&mut current_state, &ms);
    accumulate_state(state, &current_state);
}

#[inline(always)]
unsafe fn load_data_avx(x: &mut [__m128i; 8], ms: &mut MsgSchedule, data: *const __m128i) {
    #[allow(non_snake_case)]
    let MASK = _mm_setr_epi32(0x04050607, 0x00010203, 0x0c0d0e0f, 0x08090a0b);

    macro_rules! unrolled_iterations {
        ($($i:literal),*) => {$(
            x[$i] = _mm_loadu_si128(data.add($i) as *const _);
            x[$i] = _mm_shuffle_epi8(x[$i], MASK);

            let y = _mm_add_epi64(
                x[$i],
                _mm_loadu_si128(&K64[2 * $i] as *const u64 as *const _),
            );

            ms[$i] = y;
        )*};
    }

    unrolled_iterations!(0, 1, 2, 3, 4, 5, 6, 7);
}

#[inline(always)]
unsafe fn load_data_avx2(
    x: &mut [__m256i; 8],
    ms: &mut MsgSchedule,
    t2: &mut RoundStates,
    data: *const __m128i,
) {
    #[allow(non_snake_case)]
    let MASK = _mm256_set_epi64x(
        0x0809_0A0B_0C0D_0E0F_i64,
        0x0001_0203_0405_0607_i64,
        0x0809_0A0B_0C0D_0E0F_i64,
        0x0001_0203_0405_0607_i64,
    );

    macro_rules! unrolled_iterations {
        ($($i:literal),*) => {$(
            x[$i] = _mm256_insertf128_si256(x[$i], _mm_loadu_si128(data.add(8 + $i) as *const _), 1);
            x[$i] = _mm256_insertf128_si256(x[$i], _mm_loadu_si128(data.add($i) as *const _), 0);

            x[$i] = _mm256_shuffle_epi8(x[$i], MASK);

            let t = _mm_loadu_si128(K64.as_ptr().add($i * 2) as *const u64 as *const _);
            let y = _mm256_add_epi64(x[$i], _mm256_set_m128i(t, t));

            ms[$i] = _mm256_extracti128_si256(y, 0);
            t2[$i] = _mm256_extracti128_si256(y, 1);
        )*};
    }

    unrolled_iterations!(0, 1, 2, 3, 4, 5, 6, 7);
}

#[inline(always)]
unsafe fn rounds_0_63_avx(current_state: &mut State, x: &mut [__m128i; 8], ms: &mut MsgSchedule) {
    let mut k64_idx: usize = SHA512_BLOCK_WORDS_NUM;

    for _ in 0..4 {
        for j in 0..8 {
            let k64 = _mm_loadu_si128(&K64[k64_idx] as *const u64 as *const _);
            let y = sha512_update_x_avx(x, k64);

            {
                let ms = cast_ms(ms);
                sha_round(current_state, ms[2 * j]);
                sha_round(current_state, ms[2 * j + 1]);
            }

            ms[j] = y;
            k64_idx += 2;
        }
    }
}

#[inline(always)]
unsafe fn rounds_0_63_avx2(
    current_state: &mut State,
    x: &mut [__m256i; 8],
    ms: &mut MsgSchedule,
    t2: &mut RoundStates,
) {
    let mut k64x4_idx: usize = SHA512_BLOCK_WORDS_NUM;

    for i in 1..5 {
        for j in 0..8 {
            let t = _mm_loadu_si128(K64.as_ptr().add(k64x4_idx) as *const u64 as *const _);
            let y = sha512_update_x_avx2(x, _mm256_set_m128i(t, t));

            {
                let ms = cast_ms(ms);
                sha_round(current_state, ms[2 * j]);
                sha_round(current_state, ms[2 * j + 1]);
            }

            ms[j] = _mm256_extracti128_si256(y, 0);
            t2[8 * i + j] = _mm256_extracti128_si256(y, 1);

            k64x4_idx += 2;
        }
    }
}

#[inline(always)]
fn rounds_64_79(current_state: &mut State, ms: &MsgSchedule) {
    let ms = cast_ms(ms);
    for i in 64..80 {
        sha_round(current_state, ms[i & 0xf]);
    }
}

#[inline(always)]
fn process_second_block(current_state: &mut State, t2: &RoundStates) {
    for t2 in cast_rs(t2).iter() {
        sha_round(current_state, *t2);
    }
}

#[inline(always)]
fn sha_round(s: &mut State, x: u64) {
    macro_rules! big_sigma0 {
        ($a:expr) => {
            $a.rotate_right(28) ^ $a.rotate_right(34) ^ $a.rotate_right(39)
        };
    }
    macro_rules! big_sigma1 {
        ($a:expr) => {
            $a.rotate_right(14) ^ $a.rotate_right(18) ^ $a.rotate_right(41)
        };
    }
    macro_rules! bool3ary_202 {
        ($a:expr, $b:expr, $c:expr) => {
            $c ^ ($a & ($b ^ $c))
        };
    } // Choose, MD5F, SHA1C
    macro_rules! bool3ary_232 {
        ($a:expr, $b:expr, $c:expr) => {
            ($a & $b) ^ ($a & $c) ^ ($b & $c)
        };
    } // Majority, SHA1M

    macro_rules! rotate_state {
        ($s:ident) => {{
            let tmp = $s[7];
            $s[7] = $s[6];
            $s[6] = $s[5];
            $s[5] = $s[4];
            $s[4] = $s[3];
            $s[3] = $s[2];
            $s[2] = $s[1];
            $s[1] = $s[0];
            $s[0] = tmp;
        }};
    }

    let t = x
        .wrapping_add(s[7])
        .wrapping_add(big_sigma1!(s[4]))
        .wrapping_add(bool3ary_202!(s[4], s[5], s[6]));

    s[7] = t
        .wrapping_add(big_sigma0!(s[0]))
        .wrapping_add(bool3ary_232!(s[0], s[1], s[2]));
    s[3] = s[3].wrapping_add(t);

    rotate_state!(s);
}

#[inline(always)]
fn accumulate_state(dst: &mut State, src: &State) {
    for i in 0..SHA512_HASH_WORDS_NUM {
        dst[i] = dst[i].wrapping_add(src[i]);
    }
}

macro_rules! fn_sha512_update_x {
    ($name:ident, $ty:ident, {
        ADD64 = $ADD64:ident,
        ALIGNR8 = $ALIGNR8:ident,
        SRL64 = $SRL64:ident,
        SLL64 = $SLL64:ident,
        XOR = $XOR:ident,
    }) => {
        unsafe fn $name(x: &mut [$ty; 8], k64: $ty) -> $ty {
            // q[2:1]
            let mut t0 = $ALIGNR8(x[1], x[0], 8);
            // q[10:9]
            let mut t3 = $ALIGNR8(x[5], x[4], 8);
            // q[2:1] >> s0[0]
            let mut t2 = $SRL64(t0, 1);
            // q[1:0] + q[10:9]
            x[0] = $ADD64(x[0], t3);
            // q[2:1] >> s0[2]
            t3 = $SRL64(t0, 7);
            // q[2:1] << (64 - s0[1])
            let mut t1 = $SLL64(t0, 64 - 8);
            // (q[2:1] >> s0[2]) ^
            // (q[2:1] >> s0[0])
            t0 = $XOR(t3, t2);
            // q[2:1] >> s0[1]
            t2 = $SRL64(t2, 8 - 1);
            // (q[2:1] >> s0[2]) ^
            // (q[2:1] >> s0[0]) ^
            // q[2:1] << (64 - s0[1])
            t0 = $XOR(t0, t1);
            // q[2:1] << (64 - s0[0])
            t1 = $SLL64(t1, 8 - 1);
            // sigma1(q[2:1])
            t0 = $XOR(t0, t2);
            t0 = $XOR(t0, t1);
            // q[15:14] >> s1[2]
            t3 = $SRL64(x[7], 6);
            // q[15:14] >> (64 - s1[1])
            t2 = $SLL64(x[7], 64 - 61);
            // q[1:0] + sigma0(q[2:1])
            x[0] = $ADD64(x[0], t0);
            // q[15:14] >> s1[0]
            t1 = $SRL64(x[7], 19);
            // q[15:14] >> s1[2] ^
            // q[15:14] >> (64 - s1[1])
            t3 = $XOR(t3, t2);
            // q[15:14] >> (64 - s1[0])
            t2 = $SLL64(t2, 61 - 19);
            // q[15:14] >> s1[2] ^
            // q[15:14] >> (64 - s1[1] ^
            // q[15:14] >> s1[0]
            t3 = $XOR(t3, t1);
            // q[15:14] >> s1[1]
            t1 = $SRL64(t1, 61 - 19);
            // sigma1(q[15:14])
            t3 = $XOR(t3, t2);
            t3 = $XOR(t3, t1);

            // q[1:0] + q[10:9] + sigma1(q[15:14]) + sigma0(q[2:1])
            x[0] = $ADD64(x[0], t3);

            // rotate
            let temp = x[0];
            x[0] = x[1];
            x[1] = x[2];
            x[2] = x[3];
            x[3] = x[4];
            x[4] = x[5];
            x[5] = x[6];
            x[6] = x[7];
            x[7] = temp;

            $ADD64(x[7], k64)
        }
    };
}

fn_sha512_update_x!(sha512_update_x_avx, __m128i, {
        ADD64 = _mm_add_epi64,
        ALIGNR8 = _mm_alignr_epi8,
        SRL64 = _mm_srli_epi64,
        SLL64 = _mm_slli_epi64,
        XOR = _mm_xor_si128,
});

fn_sha512_update_x!(sha512_update_x_avx2, __m256i, {
        ADD64 = _mm256_add_epi64,
        ALIGNR8 = _mm256_alignr_epi8,
        SRL64 = _mm256_srli_epi64,
        SLL64 = _mm256_slli_epi64,
        XOR = _mm256_xor_si256,
});

#[inline(always)]
fn cast_ms(ms: &MsgSchedule) -> &[u64; SHA512_BLOCK_WORDS_NUM] {
    unsafe { &*(ms as *const MsgSchedule as *const _) }
}

#[inline(always)]
fn cast_rs(rs: &RoundStates) -> &[u64; SHA512_ROUNDS_NUM] {
    unsafe { &*(rs as *const RoundStates as *const _) }
}

type State = [u64; SHA512_HASH_WORDS_NUM];
type MsgSchedule = [__m128i; SHA512_BLOCK_WORDS_NUM / 2];
type RoundStates = [__m128i; SHA512_ROUNDS_NUM / 2];

const SHA512_BLOCK_BYTE_LEN: usize = 128;
const SHA512_ROUNDS_NUM: usize = 80;
const SHA512_HASH_BYTE_LEN: usize = 64;
const SHA512_HASH_WORDS_NUM: usize = SHA512_HASH_BYTE_LEN / size_of::<u64>();
const SHA512_BLOCK_WORDS_NUM: usize = SHA512_BLOCK_BYTE_LEN / size_of::<u64>();