-
Notifications
You must be signed in to change notification settings - Fork 101
/
sha3.c
153 lines (138 loc) · 5.68 KB
/
sha3.c
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
/** libkeccak-tiny
*
* A single-file implementation of SHA-3 and SHAKE.
*
* Implementor: David Leon Gil
* License: CC0, attribution kindly requested. Blame taken too,
* but not liability.
*/
#include "sha3.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/******** The Keccak-f[1600] permutation ********/
/*** Constants. ***/
static const uint8_t rho[24] = {1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 2, 14,
27, 41, 56, 8, 25, 43, 62, 18, 39, 61, 20, 44};
static const uint8_t pi[24] = {10, 7, 11, 17, 18, 3, 5, 16, 8, 21, 24, 4,
15, 23, 19, 13, 12, 2, 20, 14, 22, 9, 6, 1};
static const uint64_t RC[24] = {1ULL,
0x8082ULL,
0x800000000000808aULL,
0x8000000080008000ULL,
0x808bULL,
0x80000001ULL,
0x8000000080008081ULL,
0x8000000000008009ULL,
0x8aULL,
0x88ULL,
0x80008009ULL,
0x8000000aULL,
0x8000808bULL,
0x800000000000008bULL,
0x8000000000008089ULL,
0x8000000000008003ULL,
0x8000000000008002ULL,
0x8000000000000080ULL,
0x800aULL,
0x800000008000000aULL,
0x8000000080008081ULL,
0x8000000000008080ULL,
0x80000001ULL,
0x8000000080008008ULL};
/*** Helper macros to unroll the permutation. ***/
#define rol(x, s) (((x) << s) | ((x) >> (64 - s)))
#define REPEAT6(e) e e e e e e
#define REPEAT24(e) REPEAT6(e e e e)
#define REPEAT5(e) e e e e e
#define FOR5(v, s, e) \
v = 0; \
REPEAT5(e; v += s;)
/*** Keccak-f[1600] ***/
static inline
void keccakf(void *state) {
uint64_t *a = (uint64_t *)state;
uint64_t b[5] = {0};
uint64_t t = 0;
uint8_t x, y;
int i;
for (i = 0; i < 24; i++) {
// Theta
FOR5(x, 1, b[x] = 0; FOR5(y, 5, b[x] ^= a[x + y];))
FOR5(x, 1, FOR5(y, 5, a[y + x] ^= b[(x + 4) % 5] ^ rol(b[(x + 1) % 5], 1);))
// Rho and pi
t = a[1];
x = 0;
REPEAT24(b[0] = a[pi[x]]; a[pi[x]] = rol(t, rho[x]); t = b[0]; x++;)
// Chi
FOR5(y, 5,
FOR5(x, 1, b[x] = a[y + x];) FOR5(
x, 1, a[y + x] = b[x] ^ ((~b[(x + 1) % 5]) & b[(x + 2) % 5]);))
// Iota
a[0] ^= RC[i];
}
}
/******** The FIPS202-defined functions. ********/
/*** Some helper macros. ***/
#define _(S) \
do { \
S \
} while (0)
#define FOR(i, ST, L, S) _(size_t i; for (i = 0; i < L; i += ST) { S; })
#define mkapply_ds(NAME, S) \
static inline void NAME( \
uint8_t *dst, const uint8_t *src, size_t len) { \
FOR(i, 1, len, S); \
}
#define mkapply_sd(NAME, S) \
static inline void NAME( \
const uint8_t *src, uint8_t *dst, size_t len) { \
FOR(i, 1, len, S); \
}
mkapply_ds(xorin, dst[i] ^= src[i]) // xorin
mkapply_sd(setout, dst[i] = src[i]) // setout
#define P keccakf
#define Plen 200
// Fold P*F over the full blocks of an input.
#define foldP(I, L, F) \
while (L >= rate) { \
F(a, I, rate); \
P(a); \
I += rate; \
L -= rate; \
}
/** The sponge-based hash construction. **/
static inline
int hash(uint8_t *out, size_t outlen, const uint8_t *in, size_t inlen,
size_t rate, uint8_t delim) {
if ((out == NULL) || ((in == NULL) && inlen != 0) || (rate >= Plen)) {
return -1;
}
uint8_t a[Plen] = {0};
// Absorb input.
foldP(in, inlen, xorin);
// Xor in the DS and pad frame.
a[inlen] ^= delim;
a[rate - 1] ^= 0x80;
// Xor in the last block.
xorin(a, in, inlen);
// Apply P
P(a);
// Squeeze output.
foldP(out, outlen, setout);
setout(a, out, outlen);
memset(a, 0, 200);
return 0;
}
#define defsha3(bits) \
int sha3_##bits(uint8_t *out, size_t outlen, const uint8_t *in, \
size_t inlen) { \
if (outlen > (bits / 8)) { \
return -1; \
} \
return hash(out, outlen, in, inlen, 200 - (bits / 4), 0x01); \
}
/*** FIPS202 SHA3 FOFs ***/
defsha3(256)
defsha3(512)