slhdsa-c/sha3_f1600.c at main · h2parson/slhdsa-c · GitHub

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
/*
 * Copyright (c) The slhdsa-c project authors
 * SPDX-License-Identifier: Apache-2.0 OR ISC OR MIT
 */

/* === FIPS 202 Keccak permutation implementation for a 64-bit target. */

#include "plat_local.h"
#include "sha3_api.h"

#ifdef SLH_EXPERIMENTAL
uint64_t keccak_f1600_count = 0; /* instrumentation */
#endif

/* forward permutation */

void keccak_f1600(uint64_t x[25])
{
  /* round constants */
  static const uint64_t keccak_rc[24] = {
      UINT64_C(0x0000000000000001), UINT64_C(0x0000000000008082),
      UINT64_C(0x800000000000808A), UINT64_C(0x8000000080008000),
      UINT64_C(0x000000000000808B), UINT64_C(0x0000000080000001),
      UINT64_C(0x8000000080008081), UINT64_C(0x8000000000008009),
      UINT64_C(0x000000000000008A), UINT64_C(0x0000000000000088),
      UINT64_C(0x0000000080008009), UINT64_C(0x000000008000000A),
      UINT64_C(0x000000008000808B), UINT64_C(0x800000000000008B),
      UINT64_C(0x8000000000008089), UINT64_C(0x8000000000008003),
      UINT64_C(0x8000000000008002), UINT64_C(0x8000000000000080),
      UINT64_C(0x000000000000800A), UINT64_C(0x800000008000000A),
      UINT64_C(0x8000000080008081), UINT64_C(0x8000000000008080),
      UINT64_C(0x0000000080000001), UINT64_C(0x8000000080008008)};

  int i;
  uint64_t t, y0, y1, y2, y3, y4;

#ifdef SLH_EXPERIMENTAL
  keccak_f1600_count++; /* instrumentation */
#endif

  /* iteration */

  for (i = 0; i < 24; i++)
  {
    /* Theta */

    y4 = x[4] ^ x[9] ^ x[14] ^ x[19] ^ x[24];
    y1 = x[1] ^ x[6] ^ x[11] ^ x[16] ^ x[21];
    y3 = x[3] ^ x[8] ^ x[13] ^ x[18] ^ x[23];
    y0 = x[0] ^ x[5] ^ x[10] ^ x[15] ^ x[20];
    y2 = x[2] ^ x[7] ^ x[12] ^ x[17] ^ x[22];

    t = ror64(y4, 63);
    y4 ^= ror64(y1, 63);
    y1 ^= ror64(y3, 63);
    y3 ^= ror64(y0, 63);
    y0 ^= ror64(y2, 63);
    y2 ^= t;

    x[0] ^= y4;
    x[1] ^= y0;
    x[2] ^= y1;
    x[3] ^= y2;
    x[4] ^= y3;
    x[5] ^= y4;
    x[6] ^= y0;
    x[7] ^= y1;
    x[8] ^= y2;
    x[9] ^= y3;
    x[10] ^= y4;
    x[11] ^= y0;
    x[12] ^= y1;
    x[13] ^= y2;
    x[14] ^= y3;
    x[15] ^= y4;
    x[16] ^= y0;
    x[17] ^= y1;
    x[18] ^= y2;
    x[19] ^= y3;
    x[20] ^= y4;
    x[21] ^= y0;
    x[22] ^= y1;
    x[23] ^= y2;
    x[24] ^= y3;

    /* Rho Pi */

    t = ror64(x[1], 63);
    x[1] = ror64(x[6], 20);
    x[6] = ror64(x[9], 44);
    x[9] = ror64(x[22], 3);
    x[22] = ror64(x[14], 25);
    x[14] = ror64(x[20], 46);
    x[20] = ror64(x[2], 2);
    x[2] = ror64(x[12], 21);
    x[12] = ror64(x[13], 39);
    x[13] = ror64(x[19], 56);
    x[19] = ror64(x[23], 8);
    x[23] = ror64(x[15], 23);
    x[15] = ror64(x[4], 37);
    x[4] = ror64(x[24], 50);
    x[24] = ror64(x[21], 62);
    x[21] = ror64(x[8], 9);
    x[8] = ror64(x[16], 19);
    x[16] = ror64(x[5], 28);
    x[5] = ror64(x[3], 36);
    x[3] = ror64(x[18], 43);
    x[18] = ror64(x[17], 49);
    x[17] = ror64(x[11], 54);
    x[11] = ror64(x[7], 58);
    x[7] = ror64(x[10], 61);
    x[10] = t;

    /* Chi */

    t = x[4] & ~x[3];
    x[4] ^= x[1] & ~x[0];
    x[1] ^= x[3] & ~x[2];
    x[3] ^= x[0] & ~x[4];
    x[0] ^= x[2] & ~x[1];
    x[2] ^= t;

    t = x[9] & ~x[8];
    x[9] ^= x[6] & ~x[5];
    x[6] ^= x[8] & ~x[7];
    x[8] ^= x[5] & ~x[9];
    x[5] ^= x[7] & ~x[6];
    x[7] ^= t;

    t = x[14] & ~x[13];
    x[14] ^= x[11] & ~x[10];
    x[11] ^= x[13] & ~x[12];
    x[13] ^= x[10] & ~x[14];
    x[10] ^= x[12] & ~x[11];
    x[12] ^= t;

    t = x[19] & ~x[18];
    x[19] ^= x[16] & ~x[15];
    x[16] ^= x[18] & ~x[17];
    x[18] ^= x[15] & ~x[19];
    x[15] ^= x[17] & ~x[16];
    x[17] ^= t;

    t = x[24] & ~x[23];
    x[24] ^= x[21] & ~x[20];
    x[21] ^= x[23] & ~x[22];
    x[23] ^= x[20] & ~x[24];
    x[20] ^= x[22] & ~x[21];
    x[22] ^= t;

    /* Iota */

    x[0] = x[0] ^ keccak_rc[i];
  }
}